mirror of https://gitee.com/openkylin/linux.git
1867 lines
52 KiB
C
1867 lines
52 KiB
C
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/*
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* drivers/spi/amba-pl022.c
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*
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* A driver for the ARM PL022 PrimeCell SSP/SPI bus master.
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*
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* Copyright (C) 2008-2009 ST-Ericsson AB
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* Copyright (C) 2006 STMicroelectronics Pvt. Ltd.
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*
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* Author: Linus Walleij <linus.walleij@stericsson.com>
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*
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* Initial version inspired by:
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* linux-2.6.17-rc3-mm1/drivers/spi/pxa2xx_spi.c
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* Initial adoption to PL022 by:
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* Sachin Verma <sachin.verma@st.com>
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*/
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/*
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* TODO:
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* - add timeout on polled transfers
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* - add generic DMA framework support
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*/
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#include <linux/init.h>
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#include <linux/module.h>
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#include <linux/device.h>
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#include <linux/ioport.h>
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#include <linux/errno.h>
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#include <linux/interrupt.h>
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#include <linux/spi/spi.h>
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#include <linux/workqueue.h>
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#include <linux/errno.h>
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#include <linux/delay.h>
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#include <linux/clk.h>
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#include <linux/err.h>
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#include <linux/amba/bus.h>
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#include <linux/amba/pl022.h>
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#include <linux/io.h>
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#include <linux/delay.h>
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/*
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* This macro is used to define some register default values.
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* reg is masked with mask, the OR:ed with an (again masked)
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* val shifted sb steps to the left.
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*/
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#define SSP_WRITE_BITS(reg, val, mask, sb) \
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((reg) = (((reg) & ~(mask)) | (((val)<<(sb)) & (mask))))
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/*
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* This macro is also used to define some default values.
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* It will just shift val by sb steps to the left and mask
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* the result with mask.
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*/
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#define GEN_MASK_BITS(val, mask, sb) \
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(((val)<<(sb)) & (mask))
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#define DRIVE_TX 0
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#define DO_NOT_DRIVE_TX 1
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#define DO_NOT_QUEUE_DMA 0
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#define QUEUE_DMA 1
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#define RX_TRANSFER 1
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#define TX_TRANSFER 2
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/*
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* Macros to access SSP Registers with their offsets
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*/
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#define SSP_CR0(r) (r + 0x000)
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#define SSP_CR1(r) (r + 0x004)
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#define SSP_DR(r) (r + 0x008)
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#define SSP_SR(r) (r + 0x00C)
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#define SSP_CPSR(r) (r + 0x010)
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#define SSP_IMSC(r) (r + 0x014)
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#define SSP_RIS(r) (r + 0x018)
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#define SSP_MIS(r) (r + 0x01C)
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#define SSP_ICR(r) (r + 0x020)
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#define SSP_DMACR(r) (r + 0x024)
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#define SSP_ITCR(r) (r + 0x080)
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#define SSP_ITIP(r) (r + 0x084)
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#define SSP_ITOP(r) (r + 0x088)
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#define SSP_TDR(r) (r + 0x08C)
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#define SSP_PID0(r) (r + 0xFE0)
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#define SSP_PID1(r) (r + 0xFE4)
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#define SSP_PID2(r) (r + 0xFE8)
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#define SSP_PID3(r) (r + 0xFEC)
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#define SSP_CID0(r) (r + 0xFF0)
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#define SSP_CID1(r) (r + 0xFF4)
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#define SSP_CID2(r) (r + 0xFF8)
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#define SSP_CID3(r) (r + 0xFFC)
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/*
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* SSP Control Register 0 - SSP_CR0
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*/
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#define SSP_CR0_MASK_DSS (0x1FUL << 0)
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#define SSP_CR0_MASK_HALFDUP (0x1UL << 5)
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#define SSP_CR0_MASK_SPO (0x1UL << 6)
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#define SSP_CR0_MASK_SPH (0x1UL << 7)
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#define SSP_CR0_MASK_SCR (0xFFUL << 8)
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#define SSP_CR0_MASK_CSS (0x1FUL << 16)
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#define SSP_CR0_MASK_FRF (0x3UL << 21)
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/*
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* SSP Control Register 0 - SSP_CR1
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*/
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#define SSP_CR1_MASK_LBM (0x1UL << 0)
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#define SSP_CR1_MASK_SSE (0x1UL << 1)
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#define SSP_CR1_MASK_MS (0x1UL << 2)
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#define SSP_CR1_MASK_SOD (0x1UL << 3)
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#define SSP_CR1_MASK_RENDN (0x1UL << 4)
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#define SSP_CR1_MASK_TENDN (0x1UL << 5)
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#define SSP_CR1_MASK_MWAIT (0x1UL << 6)
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#define SSP_CR1_MASK_RXIFLSEL (0x7UL << 7)
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#define SSP_CR1_MASK_TXIFLSEL (0x7UL << 10)
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/*
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* SSP Data Register - SSP_DR
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*/
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#define SSP_DR_MASK_DATA 0xFFFFFFFF
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/*
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* SSP Status Register - SSP_SR
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*/
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#define SSP_SR_MASK_TFE (0x1UL << 0) /* Transmit FIFO empty */
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#define SSP_SR_MASK_TNF (0x1UL << 1) /* Transmit FIFO not full */
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#define SSP_SR_MASK_RNE (0x1UL << 2) /* Receive FIFO not empty */
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#define SSP_SR_MASK_RFF (0x1UL << 3) /* Receive FIFO full */
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#define SSP_SR_MASK_BSY (0x1UL << 4) /* Busy Flag */
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/*
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* SSP Clock Prescale Register - SSP_CPSR
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*/
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#define SSP_CPSR_MASK_CPSDVSR (0xFFUL << 0)
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/*
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* SSP Interrupt Mask Set/Clear Register - SSP_IMSC
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*/
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#define SSP_IMSC_MASK_RORIM (0x1UL << 0) /* Receive Overrun Interrupt mask */
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#define SSP_IMSC_MASK_RTIM (0x1UL << 1) /* Receive timeout Interrupt mask */
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#define SSP_IMSC_MASK_RXIM (0x1UL << 2) /* Receive FIFO Interrupt mask */
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#define SSP_IMSC_MASK_TXIM (0x1UL << 3) /* Transmit FIFO Interrupt mask */
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/*
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* SSP Raw Interrupt Status Register - SSP_RIS
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*/
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/* Receive Overrun Raw Interrupt status */
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#define SSP_RIS_MASK_RORRIS (0x1UL << 0)
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/* Receive Timeout Raw Interrupt status */
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#define SSP_RIS_MASK_RTRIS (0x1UL << 1)
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/* Receive FIFO Raw Interrupt status */
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#define SSP_RIS_MASK_RXRIS (0x1UL << 2)
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/* Transmit FIFO Raw Interrupt status */
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#define SSP_RIS_MASK_TXRIS (0x1UL << 3)
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/*
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* SSP Masked Interrupt Status Register - SSP_MIS
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*/
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/* Receive Overrun Masked Interrupt status */
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#define SSP_MIS_MASK_RORMIS (0x1UL << 0)
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/* Receive Timeout Masked Interrupt status */
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#define SSP_MIS_MASK_RTMIS (0x1UL << 1)
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/* Receive FIFO Masked Interrupt status */
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#define SSP_MIS_MASK_RXMIS (0x1UL << 2)
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/* Transmit FIFO Masked Interrupt status */
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#define SSP_MIS_MASK_TXMIS (0x1UL << 3)
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/*
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* SSP Interrupt Clear Register - SSP_ICR
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*/
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/* Receive Overrun Raw Clear Interrupt bit */
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#define SSP_ICR_MASK_RORIC (0x1UL << 0)
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/* Receive Timeout Clear Interrupt bit */
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#define SSP_ICR_MASK_RTIC (0x1UL << 1)
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/*
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* SSP DMA Control Register - SSP_DMACR
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*/
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/* Receive DMA Enable bit */
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#define SSP_DMACR_MASK_RXDMAE (0x1UL << 0)
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/* Transmit DMA Enable bit */
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#define SSP_DMACR_MASK_TXDMAE (0x1UL << 1)
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/*
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* SSP Integration Test control Register - SSP_ITCR
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*/
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#define SSP_ITCR_MASK_ITEN (0x1UL << 0)
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#define SSP_ITCR_MASK_TESTFIFO (0x1UL << 1)
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/*
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* SSP Integration Test Input Register - SSP_ITIP
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*/
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#define ITIP_MASK_SSPRXD (0x1UL << 0)
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#define ITIP_MASK_SSPFSSIN (0x1UL << 1)
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#define ITIP_MASK_SSPCLKIN (0x1UL << 2)
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#define ITIP_MASK_RXDMAC (0x1UL << 3)
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#define ITIP_MASK_TXDMAC (0x1UL << 4)
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#define ITIP_MASK_SSPTXDIN (0x1UL << 5)
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/*
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* SSP Integration Test output Register - SSP_ITOP
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*/
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#define ITOP_MASK_SSPTXD (0x1UL << 0)
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#define ITOP_MASK_SSPFSSOUT (0x1UL << 1)
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#define ITOP_MASK_SSPCLKOUT (0x1UL << 2)
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#define ITOP_MASK_SSPOEn (0x1UL << 3)
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#define ITOP_MASK_SSPCTLOEn (0x1UL << 4)
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#define ITOP_MASK_RORINTR (0x1UL << 5)
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#define ITOP_MASK_RTINTR (0x1UL << 6)
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#define ITOP_MASK_RXINTR (0x1UL << 7)
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#define ITOP_MASK_TXINTR (0x1UL << 8)
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#define ITOP_MASK_INTR (0x1UL << 9)
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#define ITOP_MASK_RXDMABREQ (0x1UL << 10)
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#define ITOP_MASK_RXDMASREQ (0x1UL << 11)
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#define ITOP_MASK_TXDMABREQ (0x1UL << 12)
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#define ITOP_MASK_TXDMASREQ (0x1UL << 13)
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/*
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* SSP Test Data Register - SSP_TDR
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*/
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#define TDR_MASK_TESTDATA (0xFFFFFFFF)
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/*
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* Message State
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* we use the spi_message.state (void *) pointer to
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* hold a single state value, that's why all this
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* (void *) casting is done here.
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*/
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#define STATE_START ((void *) 0)
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#define STATE_RUNNING ((void *) 1)
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#define STATE_DONE ((void *) 2)
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#define STATE_ERROR ((void *) -1)
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/*
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* Queue State
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*/
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#define QUEUE_RUNNING (0)
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#define QUEUE_STOPPED (1)
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/*
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* SSP State - Whether Enabled or Disabled
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*/
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#define SSP_DISABLED (0)
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#define SSP_ENABLED (1)
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/*
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* SSP DMA State - Whether DMA Enabled or Disabled
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*/
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#define SSP_DMA_DISABLED (0)
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#define SSP_DMA_ENABLED (1)
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/*
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* SSP Clock Defaults
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*/
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#define NMDK_SSP_DEFAULT_CLKRATE 0x2
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#define NMDK_SSP_DEFAULT_PRESCALE 0x40
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/*
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* SSP Clock Parameter ranges
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*/
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#define CPSDVR_MIN 0x02
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#define CPSDVR_MAX 0xFE
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#define SCR_MIN 0x00
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#define SCR_MAX 0xFF
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/*
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* SSP Interrupt related Macros
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*/
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#define DEFAULT_SSP_REG_IMSC 0x0UL
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#define DISABLE_ALL_INTERRUPTS DEFAULT_SSP_REG_IMSC
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#define ENABLE_ALL_INTERRUPTS (~DEFAULT_SSP_REG_IMSC)
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#define CLEAR_ALL_INTERRUPTS 0x3
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/*
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* The type of reading going on on this chip
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*/
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enum ssp_reading {
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READING_NULL,
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READING_U8,
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READING_U16,
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READING_U32
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};
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/**
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* The type of writing going on on this chip
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*/
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enum ssp_writing {
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WRITING_NULL,
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WRITING_U8,
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WRITING_U16,
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WRITING_U32
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};
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/**
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* struct vendor_data - vendor-specific config parameters
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* for PL022 derivates
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* @fifodepth: depth of FIFOs (both)
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* @max_bpw: maximum number of bits per word
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* @unidir: supports unidirection transfers
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*/
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struct vendor_data {
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int fifodepth;
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int max_bpw;
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bool unidir;
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};
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/**
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* struct pl022 - This is the private SSP driver data structure
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* @adev: AMBA device model hookup
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* @phybase: The physical memory where the SSP device resides
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* @virtbase: The virtual memory where the SSP is mapped
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* @master: SPI framework hookup
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* @master_info: controller-specific data from machine setup
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* @regs: SSP controller register's virtual address
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* @pump_messages: Work struct for scheduling work to the workqueue
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* @lock: spinlock to syncronise access to driver data
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* @workqueue: a workqueue on which any spi_message request is queued
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* @busy: workqueue is busy
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* @run: workqueue is running
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* @pump_transfers: Tasklet used in Interrupt Transfer mode
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* @cur_msg: Pointer to current spi_message being processed
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* @cur_transfer: Pointer to current spi_transfer
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* @cur_chip: pointer to current clients chip(assigned from controller_state)
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* @tx: current position in TX buffer to be read
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* @tx_end: end position in TX buffer to be read
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* @rx: current position in RX buffer to be written
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* @rx_end: end position in RX buffer to be written
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* @readingtype: the type of read currently going on
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* @writingtype: the type or write currently going on
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*/
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struct pl022 {
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struct amba_device *adev;
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struct vendor_data *vendor;
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resource_size_t phybase;
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void __iomem *virtbase;
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struct clk *clk;
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struct spi_master *master;
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struct pl022_ssp_controller *master_info;
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/* Driver message queue */
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struct workqueue_struct *workqueue;
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struct work_struct pump_messages;
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spinlock_t queue_lock;
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struct list_head queue;
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int busy;
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int run;
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/* Message transfer pump */
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struct tasklet_struct pump_transfers;
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struct spi_message *cur_msg;
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struct spi_transfer *cur_transfer;
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struct chip_data *cur_chip;
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void *tx;
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void *tx_end;
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void *rx;
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void *rx_end;
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enum ssp_reading read;
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enum ssp_writing write;
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};
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/**
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* struct chip_data - To maintain runtime state of SSP for each client chip
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* @cr0: Value of control register CR0 of SSP
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* @cr1: Value of control register CR1 of SSP
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* @dmacr: Value of DMA control Register of SSP
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* @cpsr: Value of Clock prescale register
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* @n_bytes: how many bytes(power of 2) reqd for a given data width of client
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* @enable_dma: Whether to enable DMA or not
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* @write: function ptr to be used to write when doing xfer for this chip
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* @read: function ptr to be used to read when doing xfer for this chip
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* @cs_control: chip select callback provided by chip
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* @xfer_type: polling/interrupt/DMA
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*
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* Runtime state of the SSP controller, maintained per chip,
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* This would be set according to the current message that would be served
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*/
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struct chip_data {
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u16 cr0;
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u16 cr1;
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u16 dmacr;
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u16 cpsr;
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u8 n_bytes;
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u8 enable_dma:1;
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enum ssp_reading read;
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enum ssp_writing write;
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void (*cs_control) (u32 command);
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int xfer_type;
|
||
|
};
|
||
|
|
||
|
/**
|
||
|
* null_cs_control - Dummy chip select function
|
||
|
* @command: select/delect the chip
|
||
|
*
|
||
|
* If no chip select function is provided by client this is used as dummy
|
||
|
* chip select
|
||
|
*/
|
||
|
static void null_cs_control(u32 command)
|
||
|
{
|
||
|
pr_debug("pl022: dummy chip select control, CS=0x%x\n", command);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* giveback - current spi_message is over, schedule next message and call
|
||
|
* callback of this message. Assumes that caller already
|
||
|
* set message->status; dma and pio irqs are blocked
|
||
|
* @pl022: SSP driver private data structure
|
||
|
*/
|
||
|
static void giveback(struct pl022 *pl022)
|
||
|
{
|
||
|
struct spi_transfer *last_transfer;
|
||
|
unsigned long flags;
|
||
|
struct spi_message *msg;
|
||
|
void (*curr_cs_control) (u32 command);
|
||
|
|
||
|
/*
|
||
|
* This local reference to the chip select function
|
||
|
* is needed because we set curr_chip to NULL
|
||
|
* as a step toward termininating the message.
|
||
|
*/
|
||
|
curr_cs_control = pl022->cur_chip->cs_control;
|
||
|
spin_lock_irqsave(&pl022->queue_lock, flags);
|
||
|
msg = pl022->cur_msg;
|
||
|
pl022->cur_msg = NULL;
|
||
|
pl022->cur_transfer = NULL;
|
||
|
pl022->cur_chip = NULL;
|
||
|
queue_work(pl022->workqueue, &pl022->pump_messages);
|
||
|
spin_unlock_irqrestore(&pl022->queue_lock, flags);
|
||
|
|
||
|
last_transfer = list_entry(msg->transfers.prev,
|
||
|
struct spi_transfer,
|
||
|
transfer_list);
|
||
|
|
||
|
/* Delay if requested before any change in chip select */
|
||
|
if (last_transfer->delay_usecs)
|
||
|
/*
|
||
|
* FIXME: This runs in interrupt context.
|
||
|
* Is this really smart?
|
||
|
*/
|
||
|
udelay(last_transfer->delay_usecs);
|
||
|
|
||
|
/*
|
||
|
* Drop chip select UNLESS cs_change is true or we are returning
|
||
|
* a message with an error, or next message is for another chip
|
||
|
*/
|
||
|
if (!last_transfer->cs_change)
|
||
|
curr_cs_control(SSP_CHIP_DESELECT);
|
||
|
else {
|
||
|
struct spi_message *next_msg;
|
||
|
|
||
|
/* Holding of cs was hinted, but we need to make sure
|
||
|
* the next message is for the same chip. Don't waste
|
||
|
* time with the following tests unless this was hinted.
|
||
|
*
|
||
|
* We cannot postpone this until pump_messages, because
|
||
|
* after calling msg->complete (below) the driver that
|
||
|
* sent the current message could be unloaded, which
|
||
|
* could invalidate the cs_control() callback...
|
||
|
*/
|
||
|
|
||
|
/* get a pointer to the next message, if any */
|
||
|
spin_lock_irqsave(&pl022->queue_lock, flags);
|
||
|
if (list_empty(&pl022->queue))
|
||
|
next_msg = NULL;
|
||
|
else
|
||
|
next_msg = list_entry(pl022->queue.next,
|
||
|
struct spi_message, queue);
|
||
|
spin_unlock_irqrestore(&pl022->queue_lock, flags);
|
||
|
|
||
|
/* see if the next and current messages point
|
||
|
* to the same chip
|
||
|
*/
|
||
|
if (next_msg && next_msg->spi != msg->spi)
|
||
|
next_msg = NULL;
|
||
|
if (!next_msg || msg->state == STATE_ERROR)
|
||
|
curr_cs_control(SSP_CHIP_DESELECT);
|
||
|
}
|
||
|
msg->state = NULL;
|
||
|
if (msg->complete)
|
||
|
msg->complete(msg->context);
|
||
|
/* This message is completed, so let's turn off the clock! */
|
||
|
clk_disable(pl022->clk);
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* flush - flush the FIFO to reach a clean state
|
||
|
* @pl022: SSP driver private data structure
|
||
|
*/
|
||
|
static int flush(struct pl022 *pl022)
|
||
|
{
|
||
|
unsigned long limit = loops_per_jiffy << 1;
|
||
|
|
||
|
dev_dbg(&pl022->adev->dev, "flush\n");
|
||
|
do {
|
||
|
while (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
|
||
|
readw(SSP_DR(pl022->virtbase));
|
||
|
} while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_BSY) && limit--);
|
||
|
return limit;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* restore_state - Load configuration of current chip
|
||
|
* @pl022: SSP driver private data structure
|
||
|
*/
|
||
|
static void restore_state(struct pl022 *pl022)
|
||
|
{
|
||
|
struct chip_data *chip = pl022->cur_chip;
|
||
|
|
||
|
writew(chip->cr0, SSP_CR0(pl022->virtbase));
|
||
|
writew(chip->cr1, SSP_CR1(pl022->virtbase));
|
||
|
writew(chip->dmacr, SSP_DMACR(pl022->virtbase));
|
||
|
writew(chip->cpsr, SSP_CPSR(pl022->virtbase));
|
||
|
writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
|
||
|
writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* load_ssp_default_config - Load default configuration for SSP
|
||
|
* @pl022: SSP driver private data structure
|
||
|
*/
|
||
|
|
||
|
/*
|
||
|
* Default SSP Register Values
|
||
|
*/
|
||
|
#define DEFAULT_SSP_REG_CR0 ( \
|
||
|
GEN_MASK_BITS(SSP_DATA_BITS_12, SSP_CR0_MASK_DSS, 0) | \
|
||
|
GEN_MASK_BITS(SSP_MICROWIRE_CHANNEL_FULL_DUPLEX, SSP_CR0_MASK_HALFDUP, 5) | \
|
||
|
GEN_MASK_BITS(SSP_CLK_POL_IDLE_LOW, SSP_CR0_MASK_SPO, 6) | \
|
||
|
GEN_MASK_BITS(SSP_CLK_FALLING_EDGE, SSP_CR0_MASK_SPH, 7) | \
|
||
|
GEN_MASK_BITS(NMDK_SSP_DEFAULT_CLKRATE, SSP_CR0_MASK_SCR, 8) | \
|
||
|
GEN_MASK_BITS(SSP_BITS_8, SSP_CR0_MASK_CSS, 16) | \
|
||
|
GEN_MASK_BITS(SSP_INTERFACE_MOTOROLA_SPI, SSP_CR0_MASK_FRF, 21) \
|
||
|
)
|
||
|
|
||
|
#define DEFAULT_SSP_REG_CR1 ( \
|
||
|
GEN_MASK_BITS(LOOPBACK_DISABLED, SSP_CR1_MASK_LBM, 0) | \
|
||
|
GEN_MASK_BITS(SSP_DISABLED, SSP_CR1_MASK_SSE, 1) | \
|
||
|
GEN_MASK_BITS(SSP_MASTER, SSP_CR1_MASK_MS, 2) | \
|
||
|
GEN_MASK_BITS(DO_NOT_DRIVE_TX, SSP_CR1_MASK_SOD, 3) | \
|
||
|
GEN_MASK_BITS(SSP_RX_MSB, SSP_CR1_MASK_RENDN, 4) | \
|
||
|
GEN_MASK_BITS(SSP_TX_MSB, SSP_CR1_MASK_TENDN, 5) | \
|
||
|
GEN_MASK_BITS(SSP_MWIRE_WAIT_ZERO, SSP_CR1_MASK_MWAIT, 6) |\
|
||
|
GEN_MASK_BITS(SSP_RX_1_OR_MORE_ELEM, SSP_CR1_MASK_RXIFLSEL, 7) | \
|
||
|
GEN_MASK_BITS(SSP_TX_1_OR_MORE_EMPTY_LOC, SSP_CR1_MASK_TXIFLSEL, 10) \
|
||
|
)
|
||
|
|
||
|
#define DEFAULT_SSP_REG_CPSR ( \
|
||
|
GEN_MASK_BITS(NMDK_SSP_DEFAULT_PRESCALE, SSP_CPSR_MASK_CPSDVSR, 0) \
|
||
|
)
|
||
|
|
||
|
#define DEFAULT_SSP_REG_DMACR (\
|
||
|
GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_RXDMAE, 0) | \
|
||
|
GEN_MASK_BITS(SSP_DMA_DISABLED, SSP_DMACR_MASK_TXDMAE, 1) \
|
||
|
)
|
||
|
|
||
|
|
||
|
static void load_ssp_default_config(struct pl022 *pl022)
|
||
|
{
|
||
|
writew(DEFAULT_SSP_REG_CR0, SSP_CR0(pl022->virtbase));
|
||
|
writew(DEFAULT_SSP_REG_CR1, SSP_CR1(pl022->virtbase));
|
||
|
writew(DEFAULT_SSP_REG_DMACR, SSP_DMACR(pl022->virtbase));
|
||
|
writew(DEFAULT_SSP_REG_CPSR, SSP_CPSR(pl022->virtbase));
|
||
|
writew(DISABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
|
||
|
writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* This will write to TX and read from RX according to the parameters
|
||
|
* set in pl022.
|
||
|
*/
|
||
|
static void readwriter(struct pl022 *pl022)
|
||
|
{
|
||
|
|
||
|
/*
|
||
|
* The FIFO depth is different inbetween primecell variants.
|
||
|
* I believe filling in too much in the FIFO might cause
|
||
|
* errons in 8bit wide transfers on ARM variants (just 8 words
|
||
|
* FIFO, means only 8x8 = 64 bits in FIFO) at least.
|
||
|
*
|
||
|
* FIXME: currently we have no logic to account for this.
|
||
|
* perhaps there is even something broken in HW regarding
|
||
|
* 8bit transfers (it doesn't fail on 16bit) so this needs
|
||
|
* more investigation...
|
||
|
*/
|
||
|
dev_dbg(&pl022->adev->dev,
|
||
|
"%s, rx: %p, rxend: %p, tx: %p, txend: %p\n",
|
||
|
__func__, pl022->rx, pl022->rx_end, pl022->tx, pl022->tx_end);
|
||
|
|
||
|
/* Read as much as you can */
|
||
|
while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
|
||
|
&& (pl022->rx < pl022->rx_end)) {
|
||
|
switch (pl022->read) {
|
||
|
case READING_NULL:
|
||
|
readw(SSP_DR(pl022->virtbase));
|
||
|
break;
|
||
|
case READING_U8:
|
||
|
*(u8 *) (pl022->rx) =
|
||
|
readw(SSP_DR(pl022->virtbase)) & 0xFFU;
|
||
|
break;
|
||
|
case READING_U16:
|
||
|
*(u16 *) (pl022->rx) =
|
||
|
(u16) readw(SSP_DR(pl022->virtbase));
|
||
|
break;
|
||
|
case READING_U32:
|
||
|
*(u32 *) (pl022->rx) =
|
||
|
readl(SSP_DR(pl022->virtbase));
|
||
|
break;
|
||
|
}
|
||
|
pl022->rx += (pl022->cur_chip->n_bytes);
|
||
|
}
|
||
|
/*
|
||
|
* Write as much as you can, while keeping an eye on the RX FIFO!
|
||
|
*/
|
||
|
while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_TNF)
|
||
|
&& (pl022->tx < pl022->tx_end)) {
|
||
|
switch (pl022->write) {
|
||
|
case WRITING_NULL:
|
||
|
writew(0x0, SSP_DR(pl022->virtbase));
|
||
|
break;
|
||
|
case WRITING_U8:
|
||
|
writew(*(u8 *) (pl022->tx), SSP_DR(pl022->virtbase));
|
||
|
break;
|
||
|
case WRITING_U16:
|
||
|
writew((*(u16 *) (pl022->tx)), SSP_DR(pl022->virtbase));
|
||
|
break;
|
||
|
case WRITING_U32:
|
||
|
writel(*(u32 *) (pl022->tx), SSP_DR(pl022->virtbase));
|
||
|
break;
|
||
|
}
|
||
|
pl022->tx += (pl022->cur_chip->n_bytes);
|
||
|
/*
|
||
|
* This inner reader takes care of things appearing in the RX
|
||
|
* FIFO as we're transmitting. This will happen a lot since the
|
||
|
* clock starts running when you put things into the TX FIFO,
|
||
|
* and then things are continously clocked into the RX FIFO.
|
||
|
*/
|
||
|
while ((readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RNE)
|
||
|
&& (pl022->rx < pl022->rx_end)) {
|
||
|
switch (pl022->read) {
|
||
|
case READING_NULL:
|
||
|
readw(SSP_DR(pl022->virtbase));
|
||
|
break;
|
||
|
case READING_U8:
|
||
|
*(u8 *) (pl022->rx) =
|
||
|
readw(SSP_DR(pl022->virtbase)) & 0xFFU;
|
||
|
break;
|
||
|
case READING_U16:
|
||
|
*(u16 *) (pl022->rx) =
|
||
|
(u16) readw(SSP_DR(pl022->virtbase));
|
||
|
break;
|
||
|
case READING_U32:
|
||
|
*(u32 *) (pl022->rx) =
|
||
|
readl(SSP_DR(pl022->virtbase));
|
||
|
break;
|
||
|
}
|
||
|
pl022->rx += (pl022->cur_chip->n_bytes);
|
||
|
}
|
||
|
}
|
||
|
/*
|
||
|
* When we exit here the TX FIFO should be full and the RX FIFO
|
||
|
* should be empty
|
||
|
*/
|
||
|
}
|
||
|
|
||
|
|
||
|
/**
|
||
|
* next_transfer - Move to the Next transfer in the current spi message
|
||
|
* @pl022: SSP driver private data structure
|
||
|
*
|
||
|
* This function moves though the linked list of spi transfers in the
|
||
|
* current spi message and returns with the state of current spi
|
||
|
* message i.e whether its last transfer is done(STATE_DONE) or
|
||
|
* Next transfer is ready(STATE_RUNNING)
|
||
|
*/
|
||
|
static void *next_transfer(struct pl022 *pl022)
|
||
|
{
|
||
|
struct spi_message *msg = pl022->cur_msg;
|
||
|
struct spi_transfer *trans = pl022->cur_transfer;
|
||
|
|
||
|
/* Move to next transfer */
|
||
|
if (trans->transfer_list.next != &msg->transfers) {
|
||
|
pl022->cur_transfer =
|
||
|
list_entry(trans->transfer_list.next,
|
||
|
struct spi_transfer, transfer_list);
|
||
|
return STATE_RUNNING;
|
||
|
}
|
||
|
return STATE_DONE;
|
||
|
}
|
||
|
/**
|
||
|
* pl022_interrupt_handler - Interrupt handler for SSP controller
|
||
|
*
|
||
|
* This function handles interrupts generated for an interrupt based transfer.
|
||
|
* If a receive overrun (ROR) interrupt is there then we disable SSP, flag the
|
||
|
* current message's state as STATE_ERROR and schedule the tasklet
|
||
|
* pump_transfers which will do the postprocessing of the current message by
|
||
|
* calling giveback(). Otherwise it reads data from RX FIFO till there is no
|
||
|
* more data, and writes data in TX FIFO till it is not full. If we complete
|
||
|
* the transfer we move to the next transfer and schedule the tasklet.
|
||
|
*/
|
||
|
static irqreturn_t pl022_interrupt_handler(int irq, void *dev_id)
|
||
|
{
|
||
|
struct pl022 *pl022 = dev_id;
|
||
|
struct spi_message *msg = pl022->cur_msg;
|
||
|
u16 irq_status = 0;
|
||
|
u16 flag = 0;
|
||
|
|
||
|
if (unlikely(!msg)) {
|
||
|
dev_err(&pl022->adev->dev,
|
||
|
"bad message state in interrupt handler");
|
||
|
/* Never fail */
|
||
|
return IRQ_HANDLED;
|
||
|
}
|
||
|
|
||
|
/* Read the Interrupt Status Register */
|
||
|
irq_status = readw(SSP_MIS(pl022->virtbase));
|
||
|
|
||
|
if (unlikely(!irq_status))
|
||
|
return IRQ_NONE;
|
||
|
|
||
|
/* This handles the error code interrupts */
|
||
|
if (unlikely(irq_status & SSP_MIS_MASK_RORMIS)) {
|
||
|
/*
|
||
|
* Overrun interrupt - bail out since our Data has been
|
||
|
* corrupted
|
||
|
*/
|
||
|
dev_err(&pl022->adev->dev,
|
||
|
"FIFO overrun\n");
|
||
|
if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_RFF)
|
||
|
dev_err(&pl022->adev->dev,
|
||
|
"RXFIFO is full\n");
|
||
|
if (readw(SSP_SR(pl022->virtbase)) & SSP_SR_MASK_TNF)
|
||
|
dev_err(&pl022->adev->dev,
|
||
|
"TXFIFO is full\n");
|
||
|
|
||
|
/*
|
||
|
* Disable and clear interrupts, disable SSP,
|
||
|
* mark message with bad status so it can be
|
||
|
* retried.
|
||
|
*/
|
||
|
writew(DISABLE_ALL_INTERRUPTS,
|
||
|
SSP_IMSC(pl022->virtbase));
|
||
|
writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
|
||
|
writew((readw(SSP_CR1(pl022->virtbase)) &
|
||
|
(~SSP_CR1_MASK_SSE)), SSP_CR1(pl022->virtbase));
|
||
|
msg->state = STATE_ERROR;
|
||
|
|
||
|
/* Schedule message queue handler */
|
||
|
tasklet_schedule(&pl022->pump_transfers);
|
||
|
return IRQ_HANDLED;
|
||
|
}
|
||
|
|
||
|
readwriter(pl022);
|
||
|
|
||
|
if ((pl022->tx == pl022->tx_end) && (flag == 0)) {
|
||
|
flag = 1;
|
||
|
/* Disable Transmit interrupt */
|
||
|
writew(readw(SSP_IMSC(pl022->virtbase)) &
|
||
|
(~SSP_IMSC_MASK_TXIM),
|
||
|
SSP_IMSC(pl022->virtbase));
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* Since all transactions must write as much as shall be read,
|
||
|
* we can conclude the entire transaction once RX is complete.
|
||
|
* At this point, all TX will always be finished.
|
||
|
*/
|
||
|
if (pl022->rx >= pl022->rx_end) {
|
||
|
writew(DISABLE_ALL_INTERRUPTS,
|
||
|
SSP_IMSC(pl022->virtbase));
|
||
|
writew(CLEAR_ALL_INTERRUPTS, SSP_ICR(pl022->virtbase));
|
||
|
if (unlikely(pl022->rx > pl022->rx_end)) {
|
||
|
dev_warn(&pl022->adev->dev, "read %u surplus "
|
||
|
"bytes (did you request an odd "
|
||
|
"number of bytes on a 16bit bus?)\n",
|
||
|
(u32) (pl022->rx - pl022->rx_end));
|
||
|
}
|
||
|
/* Update total bytes transfered */
|
||
|
msg->actual_length += pl022->cur_transfer->len;
|
||
|
if (pl022->cur_transfer->cs_change)
|
||
|
pl022->cur_chip->
|
||
|
cs_control(SSP_CHIP_DESELECT);
|
||
|
/* Move to next transfer */
|
||
|
msg->state = next_transfer(pl022);
|
||
|
tasklet_schedule(&pl022->pump_transfers);
|
||
|
return IRQ_HANDLED;
|
||
|
}
|
||
|
|
||
|
return IRQ_HANDLED;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* This sets up the pointers to memory for the next message to
|
||
|
* send out on the SPI bus.
|
||
|
*/
|
||
|
static int set_up_next_transfer(struct pl022 *pl022,
|
||
|
struct spi_transfer *transfer)
|
||
|
{
|
||
|
int residue;
|
||
|
|
||
|
/* Sanity check the message for this bus width */
|
||
|
residue = pl022->cur_transfer->len % pl022->cur_chip->n_bytes;
|
||
|
if (unlikely(residue != 0)) {
|
||
|
dev_err(&pl022->adev->dev,
|
||
|
"message of %u bytes to transmit but the current "
|
||
|
"chip bus has a data width of %u bytes!\n",
|
||
|
pl022->cur_transfer->len,
|
||
|
pl022->cur_chip->n_bytes);
|
||
|
dev_err(&pl022->adev->dev, "skipping this message\n");
|
||
|
return -EIO;
|
||
|
}
|
||
|
pl022->tx = (void *)transfer->tx_buf;
|
||
|
pl022->tx_end = pl022->tx + pl022->cur_transfer->len;
|
||
|
pl022->rx = (void *)transfer->rx_buf;
|
||
|
pl022->rx_end = pl022->rx + pl022->cur_transfer->len;
|
||
|
pl022->write =
|
||
|
pl022->tx ? pl022->cur_chip->write : WRITING_NULL;
|
||
|
pl022->read = pl022->rx ? pl022->cur_chip->read : READING_NULL;
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* pump_transfers - Tasklet function which schedules next interrupt transfer
|
||
|
* when running in interrupt transfer mode.
|
||
|
* @data: SSP driver private data structure
|
||
|
*
|
||
|
*/
|
||
|
static void pump_transfers(unsigned long data)
|
||
|
{
|
||
|
struct pl022 *pl022 = (struct pl022 *) data;
|
||
|
struct spi_message *message = NULL;
|
||
|
struct spi_transfer *transfer = NULL;
|
||
|
struct spi_transfer *previous = NULL;
|
||
|
|
||
|
/* Get current state information */
|
||
|
message = pl022->cur_msg;
|
||
|
transfer = pl022->cur_transfer;
|
||
|
|
||
|
/* Handle for abort */
|
||
|
if (message->state == STATE_ERROR) {
|
||
|
message->status = -EIO;
|
||
|
giveback(pl022);
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
/* Handle end of message */
|
||
|
if (message->state == STATE_DONE) {
|
||
|
message->status = 0;
|
||
|
giveback(pl022);
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
/* Delay if requested at end of transfer before CS change */
|
||
|
if (message->state == STATE_RUNNING) {
|
||
|
previous = list_entry(transfer->transfer_list.prev,
|
||
|
struct spi_transfer,
|
||
|
transfer_list);
|
||
|
if (previous->delay_usecs)
|
||
|
/*
|
||
|
* FIXME: This runs in interrupt context.
|
||
|
* Is this really smart?
|
||
|
*/
|
||
|
udelay(previous->delay_usecs);
|
||
|
|
||
|
/* Drop chip select only if cs_change is requested */
|
||
|
if (previous->cs_change)
|
||
|
pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
|
||
|
} else {
|
||
|
/* STATE_START */
|
||
|
message->state = STATE_RUNNING;
|
||
|
}
|
||
|
|
||
|
if (set_up_next_transfer(pl022, transfer)) {
|
||
|
message->state = STATE_ERROR;
|
||
|
message->status = -EIO;
|
||
|
giveback(pl022);
|
||
|
return;
|
||
|
}
|
||
|
/* Flush the FIFOs and let's go! */
|
||
|
flush(pl022);
|
||
|
writew(ENABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* NOT IMPLEMENTED
|
||
|
* configure_dma - It configures the DMA pipes for DMA transfers
|
||
|
* @data: SSP driver's private data structure
|
||
|
*
|
||
|
*/
|
||
|
static int configure_dma(void *data)
|
||
|
{
|
||
|
struct pl022 *pl022 = data;
|
||
|
dev_dbg(&pl022->adev->dev, "configure DMA\n");
|
||
|
return -ENOTSUPP;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* do_dma_transfer - It handles transfers of the current message
|
||
|
* if it is DMA xfer.
|
||
|
* NOT FULLY IMPLEMENTED
|
||
|
* @data: SSP driver's private data structure
|
||
|
*/
|
||
|
static void do_dma_transfer(void *data)
|
||
|
{
|
||
|
struct pl022 *pl022 = data;
|
||
|
|
||
|
if (configure_dma(data)) {
|
||
|
dev_dbg(&pl022->adev->dev, "configuration of DMA Failed!\n");
|
||
|
goto err_config_dma;
|
||
|
}
|
||
|
|
||
|
/* TODO: Implememt DMA setup of pipes here */
|
||
|
|
||
|
/* Enable target chip, set up transfer */
|
||
|
pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
|
||
|
if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
|
||
|
/* Error path */
|
||
|
pl022->cur_msg->state = STATE_ERROR;
|
||
|
pl022->cur_msg->status = -EIO;
|
||
|
giveback(pl022);
|
||
|
return;
|
||
|
}
|
||
|
/* Enable SSP */
|
||
|
writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
|
||
|
SSP_CR1(pl022->virtbase));
|
||
|
|
||
|
/* TODO: Enable the DMA transfer here */
|
||
|
return;
|
||
|
|
||
|
err_config_dma:
|
||
|
pl022->cur_msg->state = STATE_ERROR;
|
||
|
pl022->cur_msg->status = -EIO;
|
||
|
giveback(pl022);
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
static void do_interrupt_transfer(void *data)
|
||
|
{
|
||
|
struct pl022 *pl022 = data;
|
||
|
|
||
|
/* Enable target chip */
|
||
|
pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
|
||
|
if (set_up_next_transfer(pl022, pl022->cur_transfer)) {
|
||
|
/* Error path */
|
||
|
pl022->cur_msg->state = STATE_ERROR;
|
||
|
pl022->cur_msg->status = -EIO;
|
||
|
giveback(pl022);
|
||
|
return;
|
||
|
}
|
||
|
/* Enable SSP, turn on interrupts */
|
||
|
writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
|
||
|
SSP_CR1(pl022->virtbase));
|
||
|
writew(ENABLE_ALL_INTERRUPTS, SSP_IMSC(pl022->virtbase));
|
||
|
}
|
||
|
|
||
|
static void do_polling_transfer(void *data)
|
||
|
{
|
||
|
struct pl022 *pl022 = data;
|
||
|
struct spi_message *message = NULL;
|
||
|
struct spi_transfer *transfer = NULL;
|
||
|
struct spi_transfer *previous = NULL;
|
||
|
struct chip_data *chip;
|
||
|
|
||
|
chip = pl022->cur_chip;
|
||
|
message = pl022->cur_msg;
|
||
|
|
||
|
while (message->state != STATE_DONE) {
|
||
|
/* Handle for abort */
|
||
|
if (message->state == STATE_ERROR)
|
||
|
break;
|
||
|
transfer = pl022->cur_transfer;
|
||
|
|
||
|
/* Delay if requested at end of transfer */
|
||
|
if (message->state == STATE_RUNNING) {
|
||
|
previous =
|
||
|
list_entry(transfer->transfer_list.prev,
|
||
|
struct spi_transfer, transfer_list);
|
||
|
if (previous->delay_usecs)
|
||
|
udelay(previous->delay_usecs);
|
||
|
if (previous->cs_change)
|
||
|
pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
|
||
|
} else {
|
||
|
/* STATE_START */
|
||
|
message->state = STATE_RUNNING;
|
||
|
pl022->cur_chip->cs_control(SSP_CHIP_SELECT);
|
||
|
}
|
||
|
|
||
|
/* Configuration Changing Per Transfer */
|
||
|
if (set_up_next_transfer(pl022, transfer)) {
|
||
|
/* Error path */
|
||
|
message->state = STATE_ERROR;
|
||
|
break;
|
||
|
}
|
||
|
/* Flush FIFOs and enable SSP */
|
||
|
flush(pl022);
|
||
|
writew((readw(SSP_CR1(pl022->virtbase)) | SSP_CR1_MASK_SSE),
|
||
|
SSP_CR1(pl022->virtbase));
|
||
|
|
||
|
dev_dbg(&pl022->adev->dev, "POLLING TRANSFER ONGOING ... \n");
|
||
|
/* FIXME: insert a timeout so we don't hang here indefinately */
|
||
|
while (pl022->tx < pl022->tx_end || pl022->rx < pl022->rx_end)
|
||
|
readwriter(pl022);
|
||
|
|
||
|
/* Update total byte transfered */
|
||
|
message->actual_length += pl022->cur_transfer->len;
|
||
|
if (pl022->cur_transfer->cs_change)
|
||
|
pl022->cur_chip->cs_control(SSP_CHIP_DESELECT);
|
||
|
/* Move to next transfer */
|
||
|
message->state = next_transfer(pl022);
|
||
|
}
|
||
|
|
||
|
/* Handle end of message */
|
||
|
if (message->state == STATE_DONE)
|
||
|
message->status = 0;
|
||
|
else
|
||
|
message->status = -EIO;
|
||
|
|
||
|
giveback(pl022);
|
||
|
return;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* pump_messages - Workqueue function which processes spi message queue
|
||
|
* @data: pointer to private data of SSP driver
|
||
|
*
|
||
|
* This function checks if there is any spi message in the queue that
|
||
|
* needs processing and delegate control to appropriate function
|
||
|
* do_polling_transfer()/do_interrupt_transfer()/do_dma_transfer()
|
||
|
* based on the kind of the transfer
|
||
|
*
|
||
|
*/
|
||
|
static void pump_messages(struct work_struct *work)
|
||
|
{
|
||
|
struct pl022 *pl022 =
|
||
|
container_of(work, struct pl022, pump_messages);
|
||
|
unsigned long flags;
|
||
|
|
||
|
/* Lock queue and check for queue work */
|
||
|
spin_lock_irqsave(&pl022->queue_lock, flags);
|
||
|
if (list_empty(&pl022->queue) || pl022->run == QUEUE_STOPPED) {
|
||
|
pl022->busy = 0;
|
||
|
spin_unlock_irqrestore(&pl022->queue_lock, flags);
|
||
|
return;
|
||
|
}
|
||
|
/* Make sure we are not already running a message */
|
||
|
if (pl022->cur_msg) {
|
||
|
spin_unlock_irqrestore(&pl022->queue_lock, flags);
|
||
|
return;
|
||
|
}
|
||
|
/* Extract head of queue */
|
||
|
pl022->cur_msg =
|
||
|
list_entry(pl022->queue.next, struct spi_message, queue);
|
||
|
|
||
|
list_del_init(&pl022->cur_msg->queue);
|
||
|
pl022->busy = 1;
|
||
|
spin_unlock_irqrestore(&pl022->queue_lock, flags);
|
||
|
|
||
|
/* Initial message state */
|
||
|
pl022->cur_msg->state = STATE_START;
|
||
|
pl022->cur_transfer = list_entry(pl022->cur_msg->transfers.next,
|
||
|
struct spi_transfer,
|
||
|
transfer_list);
|
||
|
|
||
|
/* Setup the SPI using the per chip configuration */
|
||
|
pl022->cur_chip = spi_get_ctldata(pl022->cur_msg->spi);
|
||
|
/*
|
||
|
* We enable the clock here, then the clock will be disabled when
|
||
|
* giveback() is called in each method (poll/interrupt/DMA)
|
||
|
*/
|
||
|
clk_enable(pl022->clk);
|
||
|
restore_state(pl022);
|
||
|
flush(pl022);
|
||
|
|
||
|
if (pl022->cur_chip->xfer_type == POLLING_TRANSFER)
|
||
|
do_polling_transfer(pl022);
|
||
|
else if (pl022->cur_chip->xfer_type == INTERRUPT_TRANSFER)
|
||
|
do_interrupt_transfer(pl022);
|
||
|
else
|
||
|
do_dma_transfer(pl022);
|
||
|
}
|
||
|
|
||
|
|
||
|
static int __init init_queue(struct pl022 *pl022)
|
||
|
{
|
||
|
INIT_LIST_HEAD(&pl022->queue);
|
||
|
spin_lock_init(&pl022->queue_lock);
|
||
|
|
||
|
pl022->run = QUEUE_STOPPED;
|
||
|
pl022->busy = 0;
|
||
|
|
||
|
tasklet_init(&pl022->pump_transfers,
|
||
|
pump_transfers, (unsigned long)pl022);
|
||
|
|
||
|
INIT_WORK(&pl022->pump_messages, pump_messages);
|
||
|
pl022->workqueue = create_singlethread_workqueue(
|
||
|
dev_name(pl022->master->dev.parent));
|
||
|
if (pl022->workqueue == NULL)
|
||
|
return -EBUSY;
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
|
||
|
static int start_queue(struct pl022 *pl022)
|
||
|
{
|
||
|
unsigned long flags;
|
||
|
|
||
|
spin_lock_irqsave(&pl022->queue_lock, flags);
|
||
|
|
||
|
if (pl022->run == QUEUE_RUNNING || pl022->busy) {
|
||
|
spin_unlock_irqrestore(&pl022->queue_lock, flags);
|
||
|
return -EBUSY;
|
||
|
}
|
||
|
|
||
|
pl022->run = QUEUE_RUNNING;
|
||
|
pl022->cur_msg = NULL;
|
||
|
pl022->cur_transfer = NULL;
|
||
|
pl022->cur_chip = NULL;
|
||
|
spin_unlock_irqrestore(&pl022->queue_lock, flags);
|
||
|
|
||
|
queue_work(pl022->workqueue, &pl022->pump_messages);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
|
||
|
static int stop_queue(struct pl022 *pl022)
|
||
|
{
|
||
|
unsigned long flags;
|
||
|
unsigned limit = 500;
|
||
|
int status = 0;
|
||
|
|
||
|
spin_lock_irqsave(&pl022->queue_lock, flags);
|
||
|
|
||
|
/* This is a bit lame, but is optimized for the common execution path.
|
||
|
* A wait_queue on the pl022->busy could be used, but then the common
|
||
|
* execution path (pump_messages) would be required to call wake_up or
|
||
|
* friends on every SPI message. Do this instead */
|
||
|
pl022->run = QUEUE_STOPPED;
|
||
|
while (!list_empty(&pl022->queue) && pl022->busy && limit--) {
|
||
|
spin_unlock_irqrestore(&pl022->queue_lock, flags);
|
||
|
msleep(10);
|
||
|
spin_lock_irqsave(&pl022->queue_lock, flags);
|
||
|
}
|
||
|
|
||
|
if (!list_empty(&pl022->queue) || pl022->busy)
|
||
|
status = -EBUSY;
|
||
|
|
||
|
spin_unlock_irqrestore(&pl022->queue_lock, flags);
|
||
|
|
||
|
return status;
|
||
|
}
|
||
|
|
||
|
static int destroy_queue(struct pl022 *pl022)
|
||
|
{
|
||
|
int status;
|
||
|
|
||
|
status = stop_queue(pl022);
|
||
|
/* we are unloading the module or failing to load (only two calls
|
||
|
* to this routine), and neither call can handle a return value.
|
||
|
* However, destroy_workqueue calls flush_workqueue, and that will
|
||
|
* block until all work is done. If the reason that stop_queue
|
||
|
* timed out is that the work will never finish, then it does no
|
||
|
* good to call destroy_workqueue, so return anyway. */
|
||
|
if (status != 0)
|
||
|
return status;
|
||
|
|
||
|
destroy_workqueue(pl022->workqueue);
|
||
|
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int verify_controller_parameters(struct pl022 *pl022,
|
||
|
struct pl022_config_chip *chip_info)
|
||
|
{
|
||
|
if ((chip_info->lbm != LOOPBACK_ENABLED)
|
||
|
&& (chip_info->lbm != LOOPBACK_DISABLED)) {
|
||
|
dev_err(chip_info->dev,
|
||
|
"loopback Mode is configured incorrectly\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
if ((chip_info->iface < SSP_INTERFACE_MOTOROLA_SPI)
|
||
|
|| (chip_info->iface > SSP_INTERFACE_UNIDIRECTIONAL)) {
|
||
|
dev_err(chip_info->dev,
|
||
|
"interface is configured incorrectly\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
if ((chip_info->iface == SSP_INTERFACE_UNIDIRECTIONAL) &&
|
||
|
(!pl022->vendor->unidir)) {
|
||
|
dev_err(chip_info->dev,
|
||
|
"unidirectional mode not supported in this "
|
||
|
"hardware version\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
if ((chip_info->hierarchy != SSP_MASTER)
|
||
|
&& (chip_info->hierarchy != SSP_SLAVE)) {
|
||
|
dev_err(chip_info->dev,
|
||
|
"hierarchy is configured incorrectly\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
if (((chip_info->clk_freq).cpsdvsr < CPSDVR_MIN)
|
||
|
|| ((chip_info->clk_freq).cpsdvsr > CPSDVR_MAX)) {
|
||
|
dev_err(chip_info->dev,
|
||
|
"cpsdvsr is configured incorrectly\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
if ((chip_info->endian_rx != SSP_RX_MSB)
|
||
|
&& (chip_info->endian_rx != SSP_RX_LSB)) {
|
||
|
dev_err(chip_info->dev,
|
||
|
"RX FIFO endianess is configured incorrectly\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
if ((chip_info->endian_tx != SSP_TX_MSB)
|
||
|
&& (chip_info->endian_tx != SSP_TX_LSB)) {
|
||
|
dev_err(chip_info->dev,
|
||
|
"TX FIFO endianess is configured incorrectly\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
if ((chip_info->data_size < SSP_DATA_BITS_4)
|
||
|
|| (chip_info->data_size > SSP_DATA_BITS_32)) {
|
||
|
dev_err(chip_info->dev,
|
||
|
"DATA Size is configured incorrectly\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
if ((chip_info->com_mode != INTERRUPT_TRANSFER)
|
||
|
&& (chip_info->com_mode != DMA_TRANSFER)
|
||
|
&& (chip_info->com_mode != POLLING_TRANSFER)) {
|
||
|
dev_err(chip_info->dev,
|
||
|
"Communication mode is configured incorrectly\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
if ((chip_info->rx_lev_trig < SSP_RX_1_OR_MORE_ELEM)
|
||
|
|| (chip_info->rx_lev_trig > SSP_RX_32_OR_MORE_ELEM)) {
|
||
|
dev_err(chip_info->dev,
|
||
|
"RX FIFO Trigger Level is configured incorrectly\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
if ((chip_info->tx_lev_trig < SSP_TX_1_OR_MORE_EMPTY_LOC)
|
||
|
|| (chip_info->tx_lev_trig > SSP_TX_32_OR_MORE_EMPTY_LOC)) {
|
||
|
dev_err(chip_info->dev,
|
||
|
"TX FIFO Trigger Level is configured incorrectly\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
if (chip_info->iface == SSP_INTERFACE_MOTOROLA_SPI) {
|
||
|
if ((chip_info->clk_phase != SSP_CLK_RISING_EDGE)
|
||
|
&& (chip_info->clk_phase != SSP_CLK_FALLING_EDGE)) {
|
||
|
dev_err(chip_info->dev,
|
||
|
"Clock Phase is configured incorrectly\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
if ((chip_info->clk_pol != SSP_CLK_POL_IDLE_LOW)
|
||
|
&& (chip_info->clk_pol != SSP_CLK_POL_IDLE_HIGH)) {
|
||
|
dev_err(chip_info->dev,
|
||
|
"Clock Polarity is configured incorrectly\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
}
|
||
|
if (chip_info->iface == SSP_INTERFACE_NATIONAL_MICROWIRE) {
|
||
|
if ((chip_info->ctrl_len < SSP_BITS_4)
|
||
|
|| (chip_info->ctrl_len > SSP_BITS_32)) {
|
||
|
dev_err(chip_info->dev,
|
||
|
"CTRL LEN is configured incorrectly\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
if ((chip_info->wait_state != SSP_MWIRE_WAIT_ZERO)
|
||
|
&& (chip_info->wait_state != SSP_MWIRE_WAIT_ONE)) {
|
||
|
dev_err(chip_info->dev,
|
||
|
"Wait State is configured incorrectly\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
if ((chip_info->duplex != SSP_MICROWIRE_CHANNEL_FULL_DUPLEX)
|
||
|
&& (chip_info->duplex !=
|
||
|
SSP_MICROWIRE_CHANNEL_HALF_DUPLEX)) {
|
||
|
dev_err(chip_info->dev,
|
||
|
"DUPLEX is configured incorrectly\n");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
}
|
||
|
if (chip_info->cs_control == NULL) {
|
||
|
dev_warn(chip_info->dev,
|
||
|
"Chip Select Function is NULL for this chip\n");
|
||
|
chip_info->cs_control = null_cs_control;
|
||
|
}
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* pl022_transfer - transfer function registered to SPI master framework
|
||
|
* @spi: spi device which is requesting transfer
|
||
|
* @msg: spi message which is to handled is queued to driver queue
|
||
|
*
|
||
|
* This function is registered to the SPI framework for this SPI master
|
||
|
* controller. It will queue the spi_message in the queue of driver if
|
||
|
* the queue is not stopped and return.
|
||
|
*/
|
||
|
static int pl022_transfer(struct spi_device *spi, struct spi_message *msg)
|
||
|
{
|
||
|
struct pl022 *pl022 = spi_master_get_devdata(spi->master);
|
||
|
unsigned long flags;
|
||
|
|
||
|
spin_lock_irqsave(&pl022->queue_lock, flags);
|
||
|
|
||
|
if (pl022->run == QUEUE_STOPPED) {
|
||
|
spin_unlock_irqrestore(&pl022->queue_lock, flags);
|
||
|
return -ESHUTDOWN;
|
||
|
}
|
||
|
msg->actual_length = 0;
|
||
|
msg->status = -EINPROGRESS;
|
||
|
msg->state = STATE_START;
|
||
|
|
||
|
list_add_tail(&msg->queue, &pl022->queue);
|
||
|
if (pl022->run == QUEUE_RUNNING && !pl022->busy)
|
||
|
queue_work(pl022->workqueue, &pl022->pump_messages);
|
||
|
|
||
|
spin_unlock_irqrestore(&pl022->queue_lock, flags);
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int calculate_effective_freq(struct pl022 *pl022,
|
||
|
int freq,
|
||
|
struct ssp_clock_params *clk_freq)
|
||
|
{
|
||
|
/* Lets calculate the frequency parameters */
|
||
|
u16 cpsdvsr = 2;
|
||
|
u16 scr = 0;
|
||
|
bool freq_found = false;
|
||
|
u32 rate;
|
||
|
u32 max_tclk;
|
||
|
u32 min_tclk;
|
||
|
|
||
|
rate = clk_get_rate(pl022->clk);
|
||
|
/* cpsdvscr = 2 & scr 0 */
|
||
|
max_tclk = (rate / (CPSDVR_MIN * (1 + SCR_MIN)));
|
||
|
/* cpsdvsr = 254 & scr = 255 */
|
||
|
min_tclk = (rate / (CPSDVR_MAX * (1 + SCR_MAX)));
|
||
|
|
||
|
if ((freq <= max_tclk) && (freq >= min_tclk)) {
|
||
|
while (cpsdvsr <= CPSDVR_MAX && !freq_found) {
|
||
|
while (scr <= SCR_MAX && !freq_found) {
|
||
|
if ((rate /
|
||
|
(cpsdvsr * (1 + scr))) > freq)
|
||
|
scr += 1;
|
||
|
else {
|
||
|
/*
|
||
|
* This bool is made true when
|
||
|
* effective frequency >=
|
||
|
* target frequency is found
|
||
|
*/
|
||
|
freq_found = true;
|
||
|
if ((rate /
|
||
|
(cpsdvsr * (1 + scr))) != freq) {
|
||
|
if (scr == SCR_MIN) {
|
||
|
cpsdvsr -= 2;
|
||
|
scr = SCR_MAX;
|
||
|
} else
|
||
|
scr -= 1;
|
||
|
}
|
||
|
}
|
||
|
}
|
||
|
if (!freq_found) {
|
||
|
cpsdvsr += 2;
|
||
|
scr = SCR_MIN;
|
||
|
}
|
||
|
}
|
||
|
if (cpsdvsr != 0) {
|
||
|
dev_dbg(&pl022->adev->dev,
|
||
|
"SSP Effective Frequency is %u\n",
|
||
|
(rate / (cpsdvsr * (1 + scr))));
|
||
|
clk_freq->cpsdvsr = (u8) (cpsdvsr & 0xFF);
|
||
|
clk_freq->scr = (u8) (scr & 0xFF);
|
||
|
dev_dbg(&pl022->adev->dev,
|
||
|
"SSP cpsdvsr = %d, scr = %d\n",
|
||
|
clk_freq->cpsdvsr, clk_freq->scr);
|
||
|
}
|
||
|
} else {
|
||
|
dev_err(&pl022->adev->dev,
|
||
|
"controller data is incorrect: out of range frequency");
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* NOT IMPLEMENTED
|
||
|
* process_dma_info - Processes the DMA info provided by client drivers
|
||
|
* @chip_info: chip info provided by client device
|
||
|
* @chip: Runtime state maintained by the SSP controller for each spi device
|
||
|
*
|
||
|
* This function processes and stores DMA config provided by client driver
|
||
|
* into the runtime state maintained by the SSP controller driver
|
||
|
*/
|
||
|
static int process_dma_info(struct pl022_config_chip *chip_info,
|
||
|
struct chip_data *chip)
|
||
|
{
|
||
|
dev_err(chip_info->dev,
|
||
|
"cannot process DMA info, DMA not implemented!\n");
|
||
|
return -ENOTSUPP;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* pl022_setup - setup function registered to SPI master framework
|
||
|
* @spi: spi device which is requesting setup
|
||
|
*
|
||
|
* This function is registered to the SPI framework for this SPI master
|
||
|
* controller. If it is the first time when setup is called by this device,
|
||
|
* this function will initialize the runtime state for this chip and save
|
||
|
* the same in the device structure. Else it will update the runtime info
|
||
|
* with the updated chip info. Nothing is really being written to the
|
||
|
* controller hardware here, that is not done until the actual transfer
|
||
|
* commence.
|
||
|
*/
|
||
|
|
||
|
/* FIXME: JUST GUESSING the spi->mode bits understood by this driver */
|
||
|
#define MODEBITS (SPI_CPOL | SPI_CPHA | SPI_CS_HIGH \
|
||
|
| SPI_LSB_FIRST | SPI_LOOP)
|
||
|
|
||
|
static int pl022_setup(struct spi_device *spi)
|
||
|
{
|
||
|
struct pl022_config_chip *chip_info;
|
||
|
struct chip_data *chip;
|
||
|
int status = 0;
|
||
|
struct pl022 *pl022 = spi_master_get_devdata(spi->master);
|
||
|
|
||
|
if (spi->mode & ~MODEBITS) {
|
||
|
dev_dbg(&spi->dev, "unsupported mode bits %x\n",
|
||
|
spi->mode & ~MODEBITS);
|
||
|
return -EINVAL;
|
||
|
}
|
||
|
|
||
|
if (!spi->max_speed_hz)
|
||
|
return -EINVAL;
|
||
|
|
||
|
/* Get controller_state if one is supplied */
|
||
|
chip = spi_get_ctldata(spi);
|
||
|
|
||
|
if (chip == NULL) {
|
||
|
chip = kzalloc(sizeof(struct chip_data), GFP_KERNEL);
|
||
|
if (!chip) {
|
||
|
dev_err(&spi->dev,
|
||
|
"cannot allocate controller state\n");
|
||
|
return -ENOMEM;
|
||
|
}
|
||
|
dev_dbg(&spi->dev,
|
||
|
"allocated memory for controller's runtime state\n");
|
||
|
}
|
||
|
|
||
|
/* Get controller data if one is supplied */
|
||
|
chip_info = spi->controller_data;
|
||
|
|
||
|
if (chip_info == NULL) {
|
||
|
/* spi_board_info.controller_data not is supplied */
|
||
|
dev_dbg(&spi->dev,
|
||
|
"using default controller_data settings\n");
|
||
|
|
||
|
chip_info =
|
||
|
kzalloc(sizeof(struct pl022_config_chip), GFP_KERNEL);
|
||
|
|
||
|
if (!chip_info) {
|
||
|
dev_err(&spi->dev,
|
||
|
"cannot allocate controller data\n");
|
||
|
status = -ENOMEM;
|
||
|
goto err_first_setup;
|
||
|
}
|
||
|
|
||
|
dev_dbg(&spi->dev, "allocated memory for controller data\n");
|
||
|
|
||
|
/* Pointer back to the SPI device */
|
||
|
chip_info->dev = &spi->dev;
|
||
|
/*
|
||
|
* Set controller data default values:
|
||
|
* Polling is supported by default
|
||
|
*/
|
||
|
chip_info->lbm = LOOPBACK_DISABLED;
|
||
|
chip_info->com_mode = POLLING_TRANSFER;
|
||
|
chip_info->iface = SSP_INTERFACE_MOTOROLA_SPI;
|
||
|
chip_info->hierarchy = SSP_SLAVE;
|
||
|
chip_info->slave_tx_disable = DO_NOT_DRIVE_TX;
|
||
|
chip_info->endian_tx = SSP_TX_LSB;
|
||
|
chip_info->endian_rx = SSP_RX_LSB;
|
||
|
chip_info->data_size = SSP_DATA_BITS_12;
|
||
|
chip_info->rx_lev_trig = SSP_RX_1_OR_MORE_ELEM;
|
||
|
chip_info->tx_lev_trig = SSP_TX_1_OR_MORE_EMPTY_LOC;
|
||
|
chip_info->clk_phase = SSP_CLK_FALLING_EDGE;
|
||
|
chip_info->clk_pol = SSP_CLK_POL_IDLE_LOW;
|
||
|
chip_info->ctrl_len = SSP_BITS_8;
|
||
|
chip_info->wait_state = SSP_MWIRE_WAIT_ZERO;
|
||
|
chip_info->duplex = SSP_MICROWIRE_CHANNEL_FULL_DUPLEX;
|
||
|
chip_info->cs_control = null_cs_control;
|
||
|
} else {
|
||
|
dev_dbg(&spi->dev,
|
||
|
"using user supplied controller_data settings\n");
|
||
|
}
|
||
|
|
||
|
/*
|
||
|
* We can override with custom divisors, else we use the board
|
||
|
* frequency setting
|
||
|
*/
|
||
|
if ((0 == chip_info->clk_freq.cpsdvsr)
|
||
|
&& (0 == chip_info->clk_freq.scr)) {
|
||
|
status = calculate_effective_freq(pl022,
|
||
|
spi->max_speed_hz,
|
||
|
&chip_info->clk_freq);
|
||
|
if (status < 0)
|
||
|
goto err_config_params;
|
||
|
} else {
|
||
|
if ((chip_info->clk_freq.cpsdvsr % 2) != 0)
|
||
|
chip_info->clk_freq.cpsdvsr =
|
||
|
chip_info->clk_freq.cpsdvsr - 1;
|
||
|
}
|
||
|
status = verify_controller_parameters(pl022, chip_info);
|
||
|
if (status) {
|
||
|
dev_err(&spi->dev, "controller data is incorrect");
|
||
|
goto err_config_params;
|
||
|
}
|
||
|
/* Now set controller state based on controller data */
|
||
|
chip->xfer_type = chip_info->com_mode;
|
||
|
chip->cs_control = chip_info->cs_control;
|
||
|
|
||
|
if (chip_info->data_size <= 8) {
|
||
|
dev_dbg(&spi->dev, "1 <= n <=8 bits per word\n");
|
||
|
chip->n_bytes = 1;
|
||
|
chip->read = READING_U8;
|
||
|
chip->write = WRITING_U8;
|
||
|
} else if (chip_info->data_size <= 16) {
|
||
|
dev_dbg(&spi->dev, "9 <= n <= 16 bits per word\n");
|
||
|
chip->n_bytes = 2;
|
||
|
chip->read = READING_U16;
|
||
|
chip->write = WRITING_U16;
|
||
|
} else {
|
||
|
if (pl022->vendor->max_bpw >= 32) {
|
||
|
dev_dbg(&spi->dev, "17 <= n <= 32 bits per word\n");
|
||
|
chip->n_bytes = 4;
|
||
|
chip->read = READING_U32;
|
||
|
chip->write = WRITING_U32;
|
||
|
} else {
|
||
|
dev_err(&spi->dev,
|
||
|
"illegal data size for this controller!\n");
|
||
|
dev_err(&spi->dev,
|
||
|
"a standard pl022 can only handle "
|
||
|
"1 <= n <= 16 bit words\n");
|
||
|
goto err_config_params;
|
||
|
}
|
||
|
}
|
||
|
|
||
|
/* Now Initialize all register settings required for this chip */
|
||
|
chip->cr0 = 0;
|
||
|
chip->cr1 = 0;
|
||
|
chip->dmacr = 0;
|
||
|
chip->cpsr = 0;
|
||
|
if ((chip_info->com_mode == DMA_TRANSFER)
|
||
|
&& ((pl022->master_info)->enable_dma)) {
|
||
|
chip->enable_dma = 1;
|
||
|
dev_dbg(&spi->dev, "DMA mode set in controller state\n");
|
||
|
status = process_dma_info(chip_info, chip);
|
||
|
if (status < 0)
|
||
|
goto err_config_params;
|
||
|
SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
|
||
|
SSP_DMACR_MASK_RXDMAE, 0);
|
||
|
SSP_WRITE_BITS(chip->dmacr, SSP_DMA_ENABLED,
|
||
|
SSP_DMACR_MASK_TXDMAE, 1);
|
||
|
} else {
|
||
|
chip->enable_dma = 0;
|
||
|
dev_dbg(&spi->dev, "DMA mode NOT set in controller state\n");
|
||
|
SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
|
||
|
SSP_DMACR_MASK_RXDMAE, 0);
|
||
|
SSP_WRITE_BITS(chip->dmacr, SSP_DMA_DISABLED,
|
||
|
SSP_DMACR_MASK_TXDMAE, 1);
|
||
|
}
|
||
|
|
||
|
chip->cpsr = chip_info->clk_freq.cpsdvsr;
|
||
|
|
||
|
SSP_WRITE_BITS(chip->cr0, chip_info->data_size, SSP_CR0_MASK_DSS, 0);
|
||
|
SSP_WRITE_BITS(chip->cr0, chip_info->duplex, SSP_CR0_MASK_HALFDUP, 5);
|
||
|
SSP_WRITE_BITS(chip->cr0, chip_info->clk_pol, SSP_CR0_MASK_SPO, 6);
|
||
|
SSP_WRITE_BITS(chip->cr0, chip_info->clk_phase, SSP_CR0_MASK_SPH, 7);
|
||
|
SSP_WRITE_BITS(chip->cr0, chip_info->clk_freq.scr, SSP_CR0_MASK_SCR, 8);
|
||
|
SSP_WRITE_BITS(chip->cr0, chip_info->ctrl_len, SSP_CR0_MASK_CSS, 16);
|
||
|
SSP_WRITE_BITS(chip->cr0, chip_info->iface, SSP_CR0_MASK_FRF, 21);
|
||
|
SSP_WRITE_BITS(chip->cr1, chip_info->lbm, SSP_CR1_MASK_LBM, 0);
|
||
|
SSP_WRITE_BITS(chip->cr1, SSP_DISABLED, SSP_CR1_MASK_SSE, 1);
|
||
|
SSP_WRITE_BITS(chip->cr1, chip_info->hierarchy, SSP_CR1_MASK_MS, 2);
|
||
|
SSP_WRITE_BITS(chip->cr1, chip_info->slave_tx_disable, SSP_CR1_MASK_SOD, 3);
|
||
|
SSP_WRITE_BITS(chip->cr1, chip_info->endian_rx, SSP_CR1_MASK_RENDN, 4);
|
||
|
SSP_WRITE_BITS(chip->cr1, chip_info->endian_tx, SSP_CR1_MASK_TENDN, 5);
|
||
|
SSP_WRITE_BITS(chip->cr1, chip_info->wait_state, SSP_CR1_MASK_MWAIT, 6);
|
||
|
SSP_WRITE_BITS(chip->cr1, chip_info->rx_lev_trig, SSP_CR1_MASK_RXIFLSEL, 7);
|
||
|
SSP_WRITE_BITS(chip->cr1, chip_info->tx_lev_trig, SSP_CR1_MASK_TXIFLSEL, 10);
|
||
|
|
||
|
/* Save controller_state */
|
||
|
spi_set_ctldata(spi, chip);
|
||
|
return status;
|
||
|
err_config_params:
|
||
|
err_first_setup:
|
||
|
kfree(chip);
|
||
|
return status;
|
||
|
}
|
||
|
|
||
|
/**
|
||
|
* pl022_cleanup - cleanup function registered to SPI master framework
|
||
|
* @spi: spi device which is requesting cleanup
|
||
|
*
|
||
|
* This function is registered to the SPI framework for this SPI master
|
||
|
* controller. It will free the runtime state of chip.
|
||
|
*/
|
||
|
static void pl022_cleanup(struct spi_device *spi)
|
||
|
{
|
||
|
struct chip_data *chip = spi_get_ctldata(spi);
|
||
|
|
||
|
spi_set_ctldata(spi, NULL);
|
||
|
kfree(chip);
|
||
|
}
|
||
|
|
||
|
|
||
|
static int __init
|
||
|
pl022_probe(struct amba_device *adev, struct amba_id *id)
|
||
|
{
|
||
|
struct device *dev = &adev->dev;
|
||
|
struct pl022_ssp_controller *platform_info = adev->dev.platform_data;
|
||
|
struct spi_master *master;
|
||
|
struct pl022 *pl022 = NULL; /*Data for this driver */
|
||
|
int status = 0;
|
||
|
|
||
|
dev_info(&adev->dev,
|
||
|
"ARM PL022 driver, device ID: 0x%08x\n", adev->periphid);
|
||
|
if (platform_info == NULL) {
|
||
|
dev_err(&adev->dev, "probe - no platform data supplied\n");
|
||
|
status = -ENODEV;
|
||
|
goto err_no_pdata;
|
||
|
}
|
||
|
|
||
|
/* Allocate master with space for data */
|
||
|
master = spi_alloc_master(dev, sizeof(struct pl022));
|
||
|
if (master == NULL) {
|
||
|
dev_err(&adev->dev, "probe - cannot alloc SPI master\n");
|
||
|
status = -ENOMEM;
|
||
|
goto err_no_master;
|
||
|
}
|
||
|
|
||
|
pl022 = spi_master_get_devdata(master);
|
||
|
pl022->master = master;
|
||
|
pl022->master_info = platform_info;
|
||
|
pl022->adev = adev;
|
||
|
pl022->vendor = id->data;
|
||
|
|
||
|
/*
|
||
|
* Bus Number Which has been Assigned to this SSP controller
|
||
|
* on this board
|
||
|
*/
|
||
|
master->bus_num = platform_info->bus_id;
|
||
|
master->num_chipselect = platform_info->num_chipselect;
|
||
|
master->cleanup = pl022_cleanup;
|
||
|
master->setup = pl022_setup;
|
||
|
master->transfer = pl022_transfer;
|
||
|
|
||
|
dev_dbg(&adev->dev, "BUSNO: %d\n", master->bus_num);
|
||
|
|
||
|
status = amba_request_regions(adev, NULL);
|
||
|
if (status)
|
||
|
goto err_no_ioregion;
|
||
|
|
||
|
pl022->virtbase = ioremap(adev->res.start, resource_size(&adev->res));
|
||
|
if (pl022->virtbase == NULL) {
|
||
|
status = -ENOMEM;
|
||
|
goto err_no_ioremap;
|
||
|
}
|
||
|
printk(KERN_INFO "pl022: mapped registers from 0x%08x to %p\n",
|
||
|
adev->res.start, pl022->virtbase);
|
||
|
|
||
|
pl022->clk = clk_get(&adev->dev, NULL);
|
||
|
if (IS_ERR(pl022->clk)) {
|
||
|
status = PTR_ERR(pl022->clk);
|
||
|
dev_err(&adev->dev, "could not retrieve SSP/SPI bus clock\n");
|
||
|
goto err_no_clk;
|
||
|
}
|
||
|
|
||
|
/* Disable SSP */
|
||
|
clk_enable(pl022->clk);
|
||
|
writew((readw(SSP_CR1(pl022->virtbase)) & (~SSP_CR1_MASK_SSE)),
|
||
|
SSP_CR1(pl022->virtbase));
|
||
|
load_ssp_default_config(pl022);
|
||
|
clk_disable(pl022->clk);
|
||
|
|
||
|
status = request_irq(adev->irq[0], pl022_interrupt_handler, 0, "pl022",
|
||
|
pl022);
|
||
|
if (status < 0) {
|
||
|
dev_err(&adev->dev, "probe - cannot get IRQ (%d)\n", status);
|
||
|
goto err_no_irq;
|
||
|
}
|
||
|
/* Initialize and start queue */
|
||
|
status = init_queue(pl022);
|
||
|
if (status != 0) {
|
||
|
dev_err(&adev->dev, "probe - problem initializing queue\n");
|
||
|
goto err_init_queue;
|
||
|
}
|
||
|
status = start_queue(pl022);
|
||
|
if (status != 0) {
|
||
|
dev_err(&adev->dev, "probe - problem starting queue\n");
|
||
|
goto err_start_queue;
|
||
|
}
|
||
|
/* Register with the SPI framework */
|
||
|
amba_set_drvdata(adev, pl022);
|
||
|
status = spi_register_master(master);
|
||
|
if (status != 0) {
|
||
|
dev_err(&adev->dev,
|
||
|
"probe - problem registering spi master\n");
|
||
|
goto err_spi_register;
|
||
|
}
|
||
|
dev_dbg(dev, "probe succeded\n");
|
||
|
return 0;
|
||
|
|
||
|
err_spi_register:
|
||
|
err_start_queue:
|
||
|
err_init_queue:
|
||
|
destroy_queue(pl022);
|
||
|
free_irq(adev->irq[0], pl022);
|
||
|
err_no_irq:
|
||
|
clk_put(pl022->clk);
|
||
|
err_no_clk:
|
||
|
iounmap(pl022->virtbase);
|
||
|
err_no_ioremap:
|
||
|
amba_release_regions(adev);
|
||
|
err_no_ioregion:
|
||
|
spi_master_put(master);
|
||
|
err_no_master:
|
||
|
err_no_pdata:
|
||
|
return status;
|
||
|
}
|
||
|
|
||
|
static int __exit
|
||
|
pl022_remove(struct amba_device *adev)
|
||
|
{
|
||
|
struct pl022 *pl022 = amba_get_drvdata(adev);
|
||
|
int status = 0;
|
||
|
if (!pl022)
|
||
|
return 0;
|
||
|
|
||
|
/* Remove the queue */
|
||
|
status = destroy_queue(pl022);
|
||
|
if (status != 0) {
|
||
|
dev_err(&adev->dev,
|
||
|
"queue remove failed (%d)\n", status);
|
||
|
return status;
|
||
|
}
|
||
|
load_ssp_default_config(pl022);
|
||
|
free_irq(adev->irq[0], pl022);
|
||
|
clk_disable(pl022->clk);
|
||
|
clk_put(pl022->clk);
|
||
|
iounmap(pl022->virtbase);
|
||
|
amba_release_regions(adev);
|
||
|
tasklet_disable(&pl022->pump_transfers);
|
||
|
spi_unregister_master(pl022->master);
|
||
|
spi_master_put(pl022->master);
|
||
|
amba_set_drvdata(adev, NULL);
|
||
|
dev_dbg(&adev->dev, "remove succeded\n");
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
#ifdef CONFIG_PM
|
||
|
static int pl022_suspend(struct amba_device *adev, pm_message_t state)
|
||
|
{
|
||
|
struct pl022 *pl022 = amba_get_drvdata(adev);
|
||
|
int status = 0;
|
||
|
|
||
|
status = stop_queue(pl022);
|
||
|
if (status) {
|
||
|
dev_warn(&adev->dev, "suspend cannot stop queue\n");
|
||
|
return status;
|
||
|
}
|
||
|
|
||
|
clk_enable(pl022->clk);
|
||
|
load_ssp_default_config(pl022);
|
||
|
clk_disable(pl022->clk);
|
||
|
dev_dbg(&adev->dev, "suspended\n");
|
||
|
return 0;
|
||
|
}
|
||
|
|
||
|
static int pl022_resume(struct amba_device *adev)
|
||
|
{
|
||
|
struct pl022 *pl022 = amba_get_drvdata(adev);
|
||
|
int status = 0;
|
||
|
|
||
|
/* Start the queue running */
|
||
|
status = start_queue(pl022);
|
||
|
if (status)
|
||
|
dev_err(&adev->dev, "problem starting queue (%d)\n", status);
|
||
|
else
|
||
|
dev_dbg(&adev->dev, "resumed\n");
|
||
|
|
||
|
return status;
|
||
|
}
|
||
|
#else
|
||
|
#define pl022_suspend NULL
|
||
|
#define pl022_resume NULL
|
||
|
#endif /* CONFIG_PM */
|
||
|
|
||
|
static struct vendor_data vendor_arm = {
|
||
|
.fifodepth = 8,
|
||
|
.max_bpw = 16,
|
||
|
.unidir = false,
|
||
|
};
|
||
|
|
||
|
|
||
|
static struct vendor_data vendor_st = {
|
||
|
.fifodepth = 32,
|
||
|
.max_bpw = 32,
|
||
|
.unidir = false,
|
||
|
};
|
||
|
|
||
|
static struct amba_id pl022_ids[] = {
|
||
|
{
|
||
|
/*
|
||
|
* ARM PL022 variant, this has a 16bit wide
|
||
|
* and 8 locations deep TX/RX FIFO
|
||
|
*/
|
||
|
.id = 0x00041022,
|
||
|
.mask = 0x000fffff,
|
||
|
.data = &vendor_arm,
|
||
|
},
|
||
|
{
|
||
|
/*
|
||
|
* ST Micro derivative, this has 32bit wide
|
||
|
* and 32 locations deep TX/RX FIFO
|
||
|
*/
|
||
|
.id = 0x00108022,
|
||
|
.mask = 0xffffffff,
|
||
|
.data = &vendor_st,
|
||
|
},
|
||
|
{ 0, 0 },
|
||
|
};
|
||
|
|
||
|
static struct amba_driver pl022_driver = {
|
||
|
.drv = {
|
||
|
.name = "ssp-pl022",
|
||
|
},
|
||
|
.id_table = pl022_ids,
|
||
|
.probe = pl022_probe,
|
||
|
.remove = __exit_p(pl022_remove),
|
||
|
.suspend = pl022_suspend,
|
||
|
.resume = pl022_resume,
|
||
|
};
|
||
|
|
||
|
|
||
|
static int __init pl022_init(void)
|
||
|
{
|
||
|
return amba_driver_register(&pl022_driver);
|
||
|
}
|
||
|
|
||
|
module_init(pl022_init);
|
||
|
|
||
|
static void __exit pl022_exit(void)
|
||
|
{
|
||
|
amba_driver_unregister(&pl022_driver);
|
||
|
}
|
||
|
|
||
|
module_exit(pl022_exit);
|
||
|
|
||
|
MODULE_AUTHOR("Linus Walleij <linus.walleij@stericsson.com>");
|
||
|
MODULE_DESCRIPTION("PL022 SSP Controller Driver");
|
||
|
MODULE_LICENSE("GPL");
|