i2c: at91: split driver into core and master file

The single file i2c-at91.c has been split into core code (i2c-at91-core.c)
and master mode specific code (i2c-at91-master.c). This should enhance
maintainability and reduce ifdeffery for slave mode related code.

The code itself hasn't been touched. Shared functions only had to be made
non-static. Furthermore, includes have been cleaned up.

Signed-off-by: Juergen Fitschen <me@jue.yt>
[ludovic.desroches@microchip.com: fix checkpatch errors and use SPDX]
Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
This commit is contained in:
Juergen Fitschen 2019-02-22 10:25:21 +01:00 committed by Wolfram Sang
parent 07345ab220
commit ad7d142f89
5 changed files with 524 additions and 469 deletions

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@ -10102,7 +10102,8 @@ MICROCHIP I2C DRIVER
M: Ludovic Desroches <ludovic.desroches@microchip.com> M: Ludovic Desroches <ludovic.desroches@microchip.com>
L: linux-i2c@vger.kernel.org L: linux-i2c@vger.kernel.org
S: Supported S: Supported
F: drivers/i2c/busses/i2c-at91.c F: drivers/i2c/busses/i2c-at91.h
F: drivers/i2c/busses/i2c-at91-*.c
MICROCHIP ISC DRIVER MICROCHIP ISC DRIVER
M: Eugen Hristev <eugen.hristev@microchip.com> M: Eugen Hristev <eugen.hristev@microchip.com>

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@ -35,6 +35,7 @@ obj-$(CONFIG_I2C_POWERMAC) += i2c-powermac.o
obj-$(CONFIG_I2C_ALTERA) += i2c-altera.o obj-$(CONFIG_I2C_ALTERA) += i2c-altera.o
obj-$(CONFIG_I2C_ASPEED) += i2c-aspeed.o obj-$(CONFIG_I2C_ASPEED) += i2c-aspeed.o
obj-$(CONFIG_I2C_AT91) += i2c-at91.o obj-$(CONFIG_I2C_AT91) += i2c-at91.o
i2c-at91-objs := i2c-at91-core.o i2c-at91-master.o
obj-$(CONFIG_I2C_AU1550) += i2c-au1550.o obj-$(CONFIG_I2C_AU1550) += i2c-au1550.o
obj-$(CONFIG_I2C_AXXIA) += i2c-axxia.o obj-$(CONFIG_I2C_AXXIA) += i2c-axxia.o
obj-$(CONFIG_I2C_BCM2835) += i2c-bcm2835.o obj-$(CONFIG_I2C_BCM2835) += i2c-bcm2835.o

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@ -0,0 +1,369 @@
// SPDX-License-Identifier: GPL-2.0
/*
* i2c Support for Atmel's AT91 Two-Wire Interface (TWI)
*
* Copyright (C) 2011 Weinmann Medical GmbH
* Author: Nikolaus Voss <n.voss@weinmann.de>
*
* Evolved from original work by:
* Copyright (C) 2004 Rick Bronson
* Converted to 2.6 by Andrew Victor <andrew@sanpeople.com>
*
* Borrowed heavily from original work by:
* Copyright (C) 2000 Philip Edelbrock <phil@stimpy.netroedge.com>
*/
#include <linux/clk.h>
#include <linux/err.h>
#include <linux/i2c.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/pm_runtime.h>
#include <linux/pinctrl/consumer.h>
#include "i2c-at91.h"
unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg)
{
return readl_relaxed(dev->base + reg);
}
void at91_twi_write(struct at91_twi_dev *dev, unsigned reg, unsigned val)
{
writel_relaxed(val, dev->base + reg);
}
void at91_disable_twi_interrupts(struct at91_twi_dev *dev)
{
at91_twi_write(dev, AT91_TWI_IDR, AT91_TWI_INT_MASK);
}
void at91_twi_irq_save(struct at91_twi_dev *dev)
{
dev->imr = at91_twi_read(dev, AT91_TWI_IMR) & AT91_TWI_INT_MASK;
at91_disable_twi_interrupts(dev);
}
void at91_twi_irq_restore(struct at91_twi_dev *dev)
{
at91_twi_write(dev, AT91_TWI_IER, dev->imr);
}
void at91_init_twi_bus(struct at91_twi_dev *dev)
{
at91_disable_twi_interrupts(dev);
at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_SWRST);
at91_init_twi_bus_master(dev);
}
static struct at91_twi_pdata at91rm9200_config = {
.clk_max_div = 5,
.clk_offset = 3,
.has_unre_flag = true,
.has_alt_cmd = false,
.has_hold_field = false,
};
static struct at91_twi_pdata at91sam9261_config = {
.clk_max_div = 5,
.clk_offset = 4,
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = false,
};
static struct at91_twi_pdata at91sam9260_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = false,
};
static struct at91_twi_pdata at91sam9g20_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = false,
};
static struct at91_twi_pdata at91sam9g10_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = false,
};
static const struct platform_device_id at91_twi_devtypes[] = {
{
.name = "i2c-at91rm9200",
.driver_data = (unsigned long) &at91rm9200_config,
}, {
.name = "i2c-at91sam9261",
.driver_data = (unsigned long) &at91sam9261_config,
}, {
.name = "i2c-at91sam9260",
.driver_data = (unsigned long) &at91sam9260_config,
}, {
.name = "i2c-at91sam9g20",
.driver_data = (unsigned long) &at91sam9g20_config,
}, {
.name = "i2c-at91sam9g10",
.driver_data = (unsigned long) &at91sam9g10_config,
}, {
/* sentinel */
}
};
#if defined(CONFIG_OF)
static struct at91_twi_pdata at91sam9x5_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = false,
};
static struct at91_twi_pdata sama5d4_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = true,
};
static struct at91_twi_pdata sama5d2_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = true,
.has_alt_cmd = true,
.has_hold_field = true,
};
static const struct of_device_id atmel_twi_dt_ids[] = {
{
.compatible = "atmel,at91rm9200-i2c",
.data = &at91rm9200_config,
}, {
.compatible = "atmel,at91sam9260-i2c",
.data = &at91sam9260_config,
}, {
.compatible = "atmel,at91sam9261-i2c",
.data = &at91sam9261_config,
}, {
.compatible = "atmel,at91sam9g20-i2c",
.data = &at91sam9g20_config,
}, {
.compatible = "atmel,at91sam9g10-i2c",
.data = &at91sam9g10_config,
}, {
.compatible = "atmel,at91sam9x5-i2c",
.data = &at91sam9x5_config,
}, {
.compatible = "atmel,sama5d4-i2c",
.data = &sama5d4_config,
}, {
.compatible = "atmel,sama5d2-i2c",
.data = &sama5d2_config,
}, {
/* sentinel */
}
};
MODULE_DEVICE_TABLE(of, atmel_twi_dt_ids);
#endif
static struct at91_twi_pdata *at91_twi_get_driver_data(
struct platform_device *pdev)
{
if (pdev->dev.of_node) {
const struct of_device_id *match;
match = of_match_node(atmel_twi_dt_ids, pdev->dev.of_node);
if (!match)
return NULL;
return (struct at91_twi_pdata *)match->data;
}
return (struct at91_twi_pdata *) platform_get_device_id(pdev)->driver_data;
}
static int at91_twi_probe(struct platform_device *pdev)
{
struct at91_twi_dev *dev;
struct resource *mem;
int rc;
u32 phy_addr;
dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
dev->dev = &pdev->dev;
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!mem)
return -ENODEV;
phy_addr = mem->start;
dev->pdata = at91_twi_get_driver_data(pdev);
if (!dev->pdata)
return -ENODEV;
dev->base = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(dev->base))
return PTR_ERR(dev->base);
dev->irq = platform_get_irq(pdev, 0);
if (dev->irq < 0)
return dev->irq;
platform_set_drvdata(pdev, dev);
dev->clk = devm_clk_get(dev->dev, NULL);
if (IS_ERR(dev->clk)) {
dev_err(dev->dev, "no clock defined\n");
return -ENODEV;
}
clk_prepare_enable(dev->clk);
snprintf(dev->adapter.name, sizeof(dev->adapter.name), "AT91");
i2c_set_adapdata(&dev->adapter, dev);
dev->adapter.owner = THIS_MODULE;
dev->adapter.class = I2C_CLASS_DEPRECATED;
dev->adapter.dev.parent = dev->dev;
dev->adapter.nr = pdev->id;
dev->adapter.timeout = AT91_I2C_TIMEOUT;
dev->adapter.dev.of_node = pdev->dev.of_node;
rc = at91_twi_probe_master(pdev, phy_addr, dev);
if (rc)
return rc;
at91_init_twi_bus(dev);
pm_runtime_set_autosuspend_delay(dev->dev, AUTOSUSPEND_TIMEOUT);
pm_runtime_use_autosuspend(dev->dev);
pm_runtime_set_active(dev->dev);
pm_runtime_enable(dev->dev);
rc = i2c_add_numbered_adapter(&dev->adapter);
if (rc) {
clk_disable_unprepare(dev->clk);
pm_runtime_disable(dev->dev);
pm_runtime_set_suspended(dev->dev);
return rc;
}
dev_info(dev->dev, "AT91 i2c bus driver (hw version: %#x).\n",
at91_twi_read(dev, AT91_TWI_VER));
return 0;
}
static int at91_twi_remove(struct platform_device *pdev)
{
struct at91_twi_dev *dev = platform_get_drvdata(pdev);
i2c_del_adapter(&dev->adapter);
clk_disable_unprepare(dev->clk);
pm_runtime_disable(dev->dev);
pm_runtime_set_suspended(dev->dev);
return 0;
}
#ifdef CONFIG_PM
static int at91_twi_runtime_suspend(struct device *dev)
{
struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
clk_disable_unprepare(twi_dev->clk);
pinctrl_pm_select_sleep_state(dev);
return 0;
}
static int at91_twi_runtime_resume(struct device *dev)
{
struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
pinctrl_pm_select_default_state(dev);
return clk_prepare_enable(twi_dev->clk);
}
static int at91_twi_suspend_noirq(struct device *dev)
{
if (!pm_runtime_status_suspended(dev))
at91_twi_runtime_suspend(dev);
return 0;
}
static int at91_twi_resume_noirq(struct device *dev)
{
struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
int ret;
if (!pm_runtime_status_suspended(dev)) {
ret = at91_twi_runtime_resume(dev);
if (ret)
return ret;
}
pm_runtime_mark_last_busy(dev);
pm_request_autosuspend(dev);
at91_init_twi_bus(twi_dev);
return 0;
}
static const struct dev_pm_ops at91_twi_pm = {
.suspend_noirq = at91_twi_suspend_noirq,
.resume_noirq = at91_twi_resume_noirq,
.runtime_suspend = at91_twi_runtime_suspend,
.runtime_resume = at91_twi_runtime_resume,
};
#define at91_twi_pm_ops (&at91_twi_pm)
#else
#define at91_twi_pm_ops NULL
#endif
static struct platform_driver at91_twi_driver = {
.probe = at91_twi_probe,
.remove = at91_twi_remove,
.id_table = at91_twi_devtypes,
.driver = {
.name = "at91_i2c",
.of_match_table = of_match_ptr(atmel_twi_dt_ids),
.pm = at91_twi_pm_ops,
},
};
static int __init at91_twi_init(void)
{
return platform_driver_register(&at91_twi_driver);
}
static void __exit at91_twi_exit(void)
{
platform_driver_unregister(&at91_twi_driver);
}
subsys_initcall(at91_twi_init);
module_exit(at91_twi_exit);
MODULE_AUTHOR("Nikolaus Voss <n.voss@weinmann.de>");
MODULE_DESCRIPTION("I2C (TWI) driver for Atmel AT91");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:at91_i2c");

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@ -1,3 +1,4 @@
// SPDX-License-Identifier: GPL-2.0
/* /*
* i2c Support for Atmel's AT91 Two-Wire Interface (TWI) * i2c Support for Atmel's AT91 Two-Wire Interface (TWI)
* *
@ -10,11 +11,6 @@
* *
* Borrowed heavily from original work by: * Borrowed heavily from original work by:
* Copyright (C) 2000 Philip Edelbrock <phil@stimpy.netroedge.com> * Copyright (C) 2000 Philip Edelbrock <phil@stimpy.netroedge.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/ */
#include <linux/clk.h> #include <linux/clk.h>
@ -25,156 +21,15 @@
#include <linux/i2c.h> #include <linux/i2c.h>
#include <linux/interrupt.h> #include <linux/interrupt.h>
#include <linux/io.h> #include <linux/io.h>
#include <linux/module.h>
#include <linux/of.h> #include <linux/of.h>
#include <linux/of_device.h> #include <linux/of_device.h>
#include <linux/platform_device.h> #include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/platform_data/dma-atmel.h> #include <linux/platform_data/dma-atmel.h>
#include <linux/pm_runtime.h> #include <linux/pm_runtime.h>
#include <linux/pinctrl/consumer.h>
#define DEFAULT_TWI_CLK_HZ 100000 /* max 400 Kbits/s */ #include "i2c-at91.h"
#define AT91_I2C_TIMEOUT msecs_to_jiffies(100) /* transfer timeout */
#define AT91_I2C_DMA_THRESHOLD 8 /* enable DMA if transfer size is bigger than this threshold */
#define AUTOSUSPEND_TIMEOUT 2000
#define AT91_I2C_MAX_ALT_CMD_DATA_SIZE 256
/* AT91 TWI register definitions */ void at91_init_twi_bus_master(struct at91_twi_dev *dev)
#define AT91_TWI_CR 0x0000 /* Control Register */
#define AT91_TWI_START BIT(0) /* Send a Start Condition */
#define AT91_TWI_STOP BIT(1) /* Send a Stop Condition */
#define AT91_TWI_MSEN BIT(2) /* Master Transfer Enable */
#define AT91_TWI_MSDIS BIT(3) /* Master Transfer Disable */
#define AT91_TWI_SVEN BIT(4) /* Slave Transfer Enable */
#define AT91_TWI_SVDIS BIT(5) /* Slave Transfer Disable */
#define AT91_TWI_QUICK BIT(6) /* SMBus quick command */
#define AT91_TWI_SWRST BIT(7) /* Software Reset */
#define AT91_TWI_ACMEN BIT(16) /* Alternative Command Mode Enable */
#define AT91_TWI_ACMDIS BIT(17) /* Alternative Command Mode Disable */
#define AT91_TWI_THRCLR BIT(24) /* Transmit Holding Register Clear */
#define AT91_TWI_RHRCLR BIT(25) /* Receive Holding Register Clear */
#define AT91_TWI_LOCKCLR BIT(26) /* Lock Clear */
#define AT91_TWI_FIFOEN BIT(28) /* FIFO Enable */
#define AT91_TWI_FIFODIS BIT(29) /* FIFO Disable */
#define AT91_TWI_MMR 0x0004 /* Master Mode Register */
#define AT91_TWI_IADRSZ_1 0x0100 /* Internal Device Address Size */
#define AT91_TWI_MREAD BIT(12) /* Master Read Direction */
#define AT91_TWI_IADR 0x000c /* Internal Address Register */
#define AT91_TWI_CWGR 0x0010 /* Clock Waveform Generator Reg */
#define AT91_TWI_CWGR_HOLD_MAX 0x1f
#define AT91_TWI_CWGR_HOLD(x) (((x) & AT91_TWI_CWGR_HOLD_MAX) << 24)
#define AT91_TWI_SR 0x0020 /* Status Register */
#define AT91_TWI_TXCOMP BIT(0) /* Transmission Complete */
#define AT91_TWI_RXRDY BIT(1) /* Receive Holding Register Ready */
#define AT91_TWI_TXRDY BIT(2) /* Transmit Holding Register Ready */
#define AT91_TWI_OVRE BIT(6) /* Overrun Error */
#define AT91_TWI_UNRE BIT(7) /* Underrun Error */
#define AT91_TWI_NACK BIT(8) /* Not Acknowledged */
#define AT91_TWI_LOCK BIT(23) /* TWI Lock due to Frame Errors */
#define AT91_TWI_INT_MASK \
(AT91_TWI_TXCOMP | AT91_TWI_RXRDY | AT91_TWI_TXRDY | AT91_TWI_NACK)
#define AT91_TWI_IER 0x0024 /* Interrupt Enable Register */
#define AT91_TWI_IDR 0x0028 /* Interrupt Disable Register */
#define AT91_TWI_IMR 0x002c /* Interrupt Mask Register */
#define AT91_TWI_RHR 0x0030 /* Receive Holding Register */
#define AT91_TWI_THR 0x0034 /* Transmit Holding Register */
#define AT91_TWI_ACR 0x0040 /* Alternative Command Register */
#define AT91_TWI_ACR_DATAL(len) ((len) & 0xff)
#define AT91_TWI_ACR_DIR BIT(8)
#define AT91_TWI_FMR 0x0050 /* FIFO Mode Register */
#define AT91_TWI_FMR_TXRDYM(mode) (((mode) & 0x3) << 0)
#define AT91_TWI_FMR_TXRDYM_MASK (0x3 << 0)
#define AT91_TWI_FMR_RXRDYM(mode) (((mode) & 0x3) << 4)
#define AT91_TWI_FMR_RXRDYM_MASK (0x3 << 4)
#define AT91_TWI_ONE_DATA 0x0
#define AT91_TWI_TWO_DATA 0x1
#define AT91_TWI_FOUR_DATA 0x2
#define AT91_TWI_FLR 0x0054 /* FIFO Level Register */
#define AT91_TWI_FSR 0x0060 /* FIFO Status Register */
#define AT91_TWI_FIER 0x0064 /* FIFO Interrupt Enable Register */
#define AT91_TWI_FIDR 0x0068 /* FIFO Interrupt Disable Register */
#define AT91_TWI_FIMR 0x006c /* FIFO Interrupt Mask Register */
#define AT91_TWI_VER 0x00fc /* Version Register */
struct at91_twi_pdata {
unsigned clk_max_div;
unsigned clk_offset;
bool has_unre_flag;
bool has_alt_cmd;
bool has_hold_field;
struct at_dma_slave dma_slave;
};
struct at91_twi_dma {
struct dma_chan *chan_rx;
struct dma_chan *chan_tx;
struct scatterlist sg[2];
struct dma_async_tx_descriptor *data_desc;
enum dma_data_direction direction;
bool buf_mapped;
bool xfer_in_progress;
};
struct at91_twi_dev {
struct device *dev;
void __iomem *base;
struct completion cmd_complete;
struct clk *clk;
u8 *buf;
size_t buf_len;
struct i2c_msg *msg;
int irq;
unsigned imr;
unsigned transfer_status;
struct i2c_adapter adapter;
unsigned twi_cwgr_reg;
struct at91_twi_pdata *pdata;
bool use_dma;
bool use_alt_cmd;
bool recv_len_abort;
u32 fifo_size;
struct at91_twi_dma dma;
};
static unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg)
{
return readl_relaxed(dev->base + reg);
}
static void at91_twi_write(struct at91_twi_dev *dev, unsigned reg, unsigned val)
{
writel_relaxed(val, dev->base + reg);
}
static void at91_disable_twi_interrupts(struct at91_twi_dev *dev)
{
at91_twi_write(dev, AT91_TWI_IDR, AT91_TWI_INT_MASK);
}
static void at91_twi_irq_save(struct at91_twi_dev *dev)
{
dev->imr = at91_twi_read(dev, AT91_TWI_IMR) & AT91_TWI_INT_MASK;
at91_disable_twi_interrupts(dev);
}
static void at91_twi_irq_restore(struct at91_twi_dev *dev)
{
at91_twi_write(dev, AT91_TWI_IER, dev->imr);
}
static void at91_init_twi_bus_master(struct at91_twi_dev *dev)
{ {
/* FIFO should be enabled immediately after the software reset */ /* FIFO should be enabled immediately after the software reset */
if (dev->fifo_size) if (dev->fifo_size)
@ -184,14 +39,6 @@ static void at91_init_twi_bus_master(struct at91_twi_dev *dev)
at91_twi_write(dev, AT91_TWI_CWGR, dev->twi_cwgr_reg); at91_twi_write(dev, AT91_TWI_CWGR, dev->twi_cwgr_reg);
} }
static void at91_init_twi_bus(struct at91_twi_dev *dev)
{
at91_disable_twi_interrupts(dev);
at91_twi_write(dev, AT91_TWI_CR, AT91_TWI_SWRST);
at91_init_twi_bus_master(dev);
}
/* /*
* Calculate symmetric clock as stated in datasheet: * Calculate symmetric clock as stated in datasheet:
* twi_clk = F_MAIN / (2 * (cdiv * (1 << ckdiv) + offset)) * twi_clk = F_MAIN / (2 * (cdiv * (1 << ckdiv) + offset))
@ -839,124 +686,6 @@ static const struct i2c_algorithm at91_twi_algorithm = {
.functionality = at91_twi_func, .functionality = at91_twi_func,
}; };
static struct at91_twi_pdata at91rm9200_config = {
.clk_max_div = 5,
.clk_offset = 3,
.has_unre_flag = true,
.has_alt_cmd = false,
.has_hold_field = false,
};
static struct at91_twi_pdata at91sam9261_config = {
.clk_max_div = 5,
.clk_offset = 4,
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = false,
};
static struct at91_twi_pdata at91sam9260_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = false,
};
static struct at91_twi_pdata at91sam9g20_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = false,
};
static struct at91_twi_pdata at91sam9g10_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = false,
};
static const struct platform_device_id at91_twi_devtypes[] = {
{
.name = "i2c-at91rm9200",
.driver_data = (unsigned long) &at91rm9200_config,
}, {
.name = "i2c-at91sam9261",
.driver_data = (unsigned long) &at91sam9261_config,
}, {
.name = "i2c-at91sam9260",
.driver_data = (unsigned long) &at91sam9260_config,
}, {
.name = "i2c-at91sam9g20",
.driver_data = (unsigned long) &at91sam9g20_config,
}, {
.name = "i2c-at91sam9g10",
.driver_data = (unsigned long) &at91sam9g10_config,
}, {
/* sentinel */
}
};
#if defined(CONFIG_OF)
static struct at91_twi_pdata at91sam9x5_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = false,
};
static struct at91_twi_pdata sama5d4_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = false,
.has_alt_cmd = false,
.has_hold_field = true,
};
static struct at91_twi_pdata sama5d2_config = {
.clk_max_div = 7,
.clk_offset = 4,
.has_unre_flag = true,
.has_alt_cmd = true,
.has_hold_field = true,
};
static const struct of_device_id atmel_twi_dt_ids[] = {
{
.compatible = "atmel,at91rm9200-i2c",
.data = &at91rm9200_config,
} , {
.compatible = "atmel,at91sam9260-i2c",
.data = &at91sam9260_config,
} , {
.compatible = "atmel,at91sam9261-i2c",
.data = &at91sam9261_config,
} , {
.compatible = "atmel,at91sam9g20-i2c",
.data = &at91sam9g20_config,
} , {
.compatible = "atmel,at91sam9g10-i2c",
.data = &at91sam9g10_config,
}, {
.compatible = "atmel,at91sam9x5-i2c",
.data = &at91sam9x5_config,
}, {
.compatible = "atmel,sama5d4-i2c",
.data = &sama5d4_config,
}, {
.compatible = "atmel,sama5d2-i2c",
.data = &sama5d2_config,
}, {
/* sentinel */
}
};
MODULE_DEVICE_TABLE(of, atmel_twi_dt_ids);
#endif
static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr) static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr)
{ {
int ret = 0; int ret = 0;
@ -1039,21 +768,8 @@ static int at91_twi_configure_dma(struct at91_twi_dev *dev, u32 phy_addr)
return ret; return ret;
} }
static struct at91_twi_pdata *at91_twi_get_driver_data( int at91_twi_probe_master(struct platform_device *pdev,
struct platform_device *pdev) u32 phy_addr, struct at91_twi_dev *dev)
{
if (pdev->dev.of_node) {
const struct of_device_id *match;
match = of_match_node(atmel_twi_dt_ids, pdev->dev.of_node);
if (!match)
return NULL;
return (struct at91_twi_pdata *)match->data;
}
return (struct at91_twi_pdata *) platform_get_device_id(pdev)->driver_data;
}
static int at91_twi_probe_master(struct platform_device *pdev,
u32 phy_addr, struct at91_twi_dev *dev)
{ {
int rc; int rc;
u32 bus_clk_rate; u32 bus_clk_rate;
@ -1090,182 +806,3 @@ static int at91_twi_probe_master(struct platform_device *pdev,
return 0; return 0;
} }
static int at91_twi_probe(struct platform_device *pdev)
{
struct at91_twi_dev *dev;
struct resource *mem;
int rc;
u32 phy_addr;
dev = devm_kzalloc(&pdev->dev, sizeof(*dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
dev->dev = &pdev->dev;
mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (!mem)
return -ENODEV;
phy_addr = mem->start;
dev->pdata = at91_twi_get_driver_data(pdev);
if (!dev->pdata)
return -ENODEV;
dev->base = devm_ioremap_resource(&pdev->dev, mem);
if (IS_ERR(dev->base))
return PTR_ERR(dev->base);
dev->irq = platform_get_irq(pdev, 0);
if (dev->irq < 0)
return dev->irq;
platform_set_drvdata(pdev, dev);
dev->clk = devm_clk_get(dev->dev, NULL);
if (IS_ERR(dev->clk)) {
dev_err(dev->dev, "no clock defined\n");
return -ENODEV;
}
rc = clk_prepare_enable(dev->clk);
if (rc)
return rc;
snprintf(dev->adapter.name, sizeof(dev->adapter.name), "AT91");
i2c_set_adapdata(&dev->adapter, dev);
dev->adapter.owner = THIS_MODULE;
dev->adapter.class = I2C_CLASS_DEPRECATED;
dev->adapter.dev.parent = dev->dev;
dev->adapter.nr = pdev->id;
dev->adapter.timeout = AT91_I2C_TIMEOUT;
dev->adapter.dev.of_node = pdev->dev.of_node;
rc = at91_twi_probe_master(pdev, phy_addr, dev);
if (rc)
return rc;
at91_init_twi_bus(dev);
pm_runtime_set_autosuspend_delay(dev->dev, AUTOSUSPEND_TIMEOUT);
pm_runtime_use_autosuspend(dev->dev);
pm_runtime_set_active(dev->dev);
pm_runtime_enable(dev->dev);
rc = i2c_add_numbered_adapter(&dev->adapter);
if (rc) {
clk_disable_unprepare(dev->clk);
pm_runtime_disable(dev->dev);
pm_runtime_set_suspended(dev->dev);
return rc;
}
dev_info(dev->dev, "AT91 i2c bus driver (hw version: %#x).\n",
at91_twi_read(dev, AT91_TWI_VER));
return 0;
}
static int at91_twi_remove(struct platform_device *pdev)
{
struct at91_twi_dev *dev = platform_get_drvdata(pdev);
i2c_del_adapter(&dev->adapter);
clk_disable_unprepare(dev->clk);
pm_runtime_disable(dev->dev);
pm_runtime_set_suspended(dev->dev);
return 0;
}
#ifdef CONFIG_PM
static int at91_twi_runtime_suspend(struct device *dev)
{
struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
clk_disable_unprepare(twi_dev->clk);
pinctrl_pm_select_sleep_state(dev);
return 0;
}
static int at91_twi_runtime_resume(struct device *dev)
{
struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
pinctrl_pm_select_default_state(dev);
return clk_prepare_enable(twi_dev->clk);
}
static int at91_twi_suspend_noirq(struct device *dev)
{
if (!pm_runtime_status_suspended(dev))
at91_twi_runtime_suspend(dev);
return 0;
}
static int at91_twi_resume_noirq(struct device *dev)
{
struct at91_twi_dev *twi_dev = dev_get_drvdata(dev);
int ret;
if (!pm_runtime_status_suspended(dev)) {
ret = at91_twi_runtime_resume(dev);
if (ret)
return ret;
}
pm_runtime_mark_last_busy(dev);
pm_request_autosuspend(dev);
at91_init_twi_bus(twi_dev);
return 0;
}
static const struct dev_pm_ops at91_twi_pm = {
.suspend_noirq = at91_twi_suspend_noirq,
.resume_noirq = at91_twi_resume_noirq,
.runtime_suspend = at91_twi_runtime_suspend,
.runtime_resume = at91_twi_runtime_resume,
};
#define at91_twi_pm_ops (&at91_twi_pm)
#else
#define at91_twi_pm_ops NULL
#endif
static struct platform_driver at91_twi_driver = {
.probe = at91_twi_probe,
.remove = at91_twi_remove,
.id_table = at91_twi_devtypes,
.driver = {
.name = "at91_i2c",
.of_match_table = of_match_ptr(atmel_twi_dt_ids),
.pm = at91_twi_pm_ops,
},
};
static int __init at91_twi_init(void)
{
return platform_driver_register(&at91_twi_driver);
}
static void __exit at91_twi_exit(void)
{
platform_driver_unregister(&at91_twi_driver);
}
subsys_initcall(at91_twi_init);
module_exit(at91_twi_exit);
MODULE_AUTHOR("Nikolaus Voss <n.voss@weinmann.de>");
MODULE_DESCRIPTION("I2C (TWI) driver for Atmel AT91");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:at91_i2c");

View File

@ -0,0 +1,147 @@
/* SPDX-License-Identifier: GPL-2.0 */
/*
* i2c Support for Atmel's AT91 Two-Wire Interface (TWI)
*
* Copyright (C) 2011 Weinmann Medical GmbH
* Author: Nikolaus Voss <n.voss@weinmann.de>
*
* Evolved from original work by:
* Copyright (C) 2004 Rick Bronson
* Converted to 2.6 by Andrew Victor <andrew@sanpeople.com>
*
* Borrowed heavily from original work by:
* Copyright (C) 2000 Philip Edelbrock <phil@stimpy.netroedge.com>
*/
#include <linux/clk.h>
#include <linux/completion.h>
#include <linux/dma-mapping.h>
#include <linux/dmaengine.h>
#include <linux/i2c.h>
#include <linux/platform_data/dma-atmel.h>
#include <linux/platform_device.h>
#define DEFAULT_TWI_CLK_HZ 100000 /* max 400 Kbits/s */
#define AT91_I2C_TIMEOUT msecs_to_jiffies(100) /* transfer timeout */
#define AT91_I2C_DMA_THRESHOLD 8 /* enable DMA if transfer size is bigger than this threshold */
#define AUTOSUSPEND_TIMEOUT 2000
#define AT91_I2C_MAX_ALT_CMD_DATA_SIZE 256
/* AT91 TWI register definitions */
#define AT91_TWI_CR 0x0000 /* Control Register */
#define AT91_TWI_START BIT(0) /* Send a Start Condition */
#define AT91_TWI_STOP BIT(1) /* Send a Stop Condition */
#define AT91_TWI_MSEN BIT(2) /* Master Transfer Enable */
#define AT91_TWI_MSDIS BIT(3) /* Master Transfer Disable */
#define AT91_TWI_SVEN BIT(4) /* Slave Transfer Enable */
#define AT91_TWI_SVDIS BIT(5) /* Slave Transfer Disable */
#define AT91_TWI_QUICK BIT(6) /* SMBus quick command */
#define AT91_TWI_SWRST BIT(7) /* Software Reset */
#define AT91_TWI_ACMEN BIT(16) /* Alternative Command Mode Enable */
#define AT91_TWI_ACMDIS BIT(17) /* Alternative Command Mode Disable */
#define AT91_TWI_THRCLR BIT(24) /* Transmit Holding Register Clear */
#define AT91_TWI_RHRCLR BIT(25) /* Receive Holding Register Clear */
#define AT91_TWI_LOCKCLR BIT(26) /* Lock Clear */
#define AT91_TWI_FIFOEN BIT(28) /* FIFO Enable */
#define AT91_TWI_FIFODIS BIT(29) /* FIFO Disable */
#define AT91_TWI_MMR 0x0004 /* Master Mode Register */
#define AT91_TWI_IADRSZ_1 0x0100 /* Internal Device Address Size */
#define AT91_TWI_MREAD BIT(12) /* Master Read Direction */
#define AT91_TWI_IADR 0x000c /* Internal Address Register */
#define AT91_TWI_CWGR 0x0010 /* Clock Waveform Generator Reg */
#define AT91_TWI_CWGR_HOLD_MAX 0x1f
#define AT91_TWI_CWGR_HOLD(x) (((x) & AT91_TWI_CWGR_HOLD_MAX) << 24)
#define AT91_TWI_SR 0x0020 /* Status Register */
#define AT91_TWI_TXCOMP BIT(0) /* Transmission Complete */
#define AT91_TWI_RXRDY BIT(1) /* Receive Holding Register Ready */
#define AT91_TWI_TXRDY BIT(2) /* Transmit Holding Register Ready */
#define AT91_TWI_OVRE BIT(6) /* Overrun Error */
#define AT91_TWI_UNRE BIT(7) /* Underrun Error */
#define AT91_TWI_NACK BIT(8) /* Not Acknowledged */
#define AT91_TWI_LOCK BIT(23) /* TWI Lock due to Frame Errors */
#define AT91_TWI_INT_MASK \
(AT91_TWI_TXCOMP | AT91_TWI_RXRDY | AT91_TWI_TXRDY | AT91_TWI_NACK)
#define AT91_TWI_IER 0x0024 /* Interrupt Enable Register */
#define AT91_TWI_IDR 0x0028 /* Interrupt Disable Register */
#define AT91_TWI_IMR 0x002c /* Interrupt Mask Register */
#define AT91_TWI_RHR 0x0030 /* Receive Holding Register */
#define AT91_TWI_THR 0x0034 /* Transmit Holding Register */
#define AT91_TWI_ACR 0x0040 /* Alternative Command Register */
#define AT91_TWI_ACR_DATAL(len) ((len) & 0xff)
#define AT91_TWI_ACR_DIR BIT(8)
#define AT91_TWI_FMR 0x0050 /* FIFO Mode Register */
#define AT91_TWI_FMR_TXRDYM(mode) (((mode) & 0x3) << 0)
#define AT91_TWI_FMR_TXRDYM_MASK (0x3 << 0)
#define AT91_TWI_FMR_RXRDYM(mode) (((mode) & 0x3) << 4)
#define AT91_TWI_FMR_RXRDYM_MASK (0x3 << 4)
#define AT91_TWI_ONE_DATA 0x0
#define AT91_TWI_TWO_DATA 0x1
#define AT91_TWI_FOUR_DATA 0x2
#define AT91_TWI_FLR 0x0054 /* FIFO Level Register */
#define AT91_TWI_FSR 0x0060 /* FIFO Status Register */
#define AT91_TWI_FIER 0x0064 /* FIFO Interrupt Enable Register */
#define AT91_TWI_FIDR 0x0068 /* FIFO Interrupt Disable Register */
#define AT91_TWI_FIMR 0x006c /* FIFO Interrupt Mask Register */
#define AT91_TWI_VER 0x00fc /* Version Register */
struct at91_twi_pdata {
unsigned clk_max_div;
unsigned clk_offset;
bool has_unre_flag;
bool has_alt_cmd;
bool has_hold_field;
struct at_dma_slave dma_slave;
};
struct at91_twi_dma {
struct dma_chan *chan_rx;
struct dma_chan *chan_tx;
struct scatterlist sg[2];
struct dma_async_tx_descriptor *data_desc;
enum dma_data_direction direction;
bool buf_mapped;
bool xfer_in_progress;
};
struct at91_twi_dev {
struct device *dev;
void __iomem *base;
struct completion cmd_complete;
struct clk *clk;
u8 *buf;
size_t buf_len;
struct i2c_msg *msg;
int irq;
unsigned imr;
unsigned transfer_status;
struct i2c_adapter adapter;
unsigned twi_cwgr_reg;
struct at91_twi_pdata *pdata;
bool use_dma;
bool use_alt_cmd;
bool recv_len_abort;
u32 fifo_size;
struct at91_twi_dma dma;
};
unsigned at91_twi_read(struct at91_twi_dev *dev, unsigned reg);
void at91_twi_write(struct at91_twi_dev *dev, unsigned reg, unsigned val);
void at91_disable_twi_interrupts(struct at91_twi_dev *dev);
void at91_twi_irq_save(struct at91_twi_dev *dev);
void at91_twi_irq_restore(struct at91_twi_dev *dev);
void at91_init_twi_bus(struct at91_twi_dev *dev);
void at91_init_twi_bus_master(struct at91_twi_dev *dev);
int at91_twi_probe_master(struct platform_device *pdev, u32 phy_addr,
struct at91_twi_dev *dev);