linux/arch/arm/mach-omap2/serial.c

333 lines
8.9 KiB
C

/*
* arch/arm/mach-omap2/serial.c
*
* OMAP2 serial support.
*
* Copyright (C) 2005-2008 Nokia Corporation
* Author: Paul Mundt <paul.mundt@nokia.com>
*
* Major rework for PM support by Kevin Hilman
*
* Based off of arch/arm/mach-omap/omap1/serial.c
*
* Copyright (C) 2009 Texas Instruments
* Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com
*
* This file is subject to the terms and conditions of the GNU General Public
* License. See the file "COPYING" in the main directory of this archive
* for more details.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/clk.h>
#include <linux/io.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/pm_runtime.h>
#include <linux/console.h>
#include <linux/omap-dma.h>
#include <linux/platform_data/serial-omap.h>
#include "common.h"
#include "omap_hwmod.h"
#include "omap_device.h"
#include "omap-pm.h"
#include "soc.h"
#include "prm2xxx_3xxx.h"
#include "pm.h"
#include "cm2xxx_3xxx.h"
#include "prm-regbits-34xx.h"
#include "control.h"
#include "mux.h"
#include "serial.h"
/*
* NOTE: By default the serial auto_suspend timeout is disabled as it causes
* lost characters over the serial ports. This means that the UART clocks will
* stay on until power/autosuspend_delay is set for the uart from sysfs.
* This also causes that any deeper omap sleep states are blocked.
*/
#define DEFAULT_AUTOSUSPEND_DELAY -1
#define MAX_UART_HWMOD_NAME_LEN 16
struct omap_uart_state {
int num;
struct list_head node;
struct omap_hwmod *oh;
struct omap_device_pad default_omap_uart_pads[2];
};
static LIST_HEAD(uart_list);
static u8 num_uarts;
static u8 console_uart_id = -1;
static u8 uart_debug;
#define DEFAULT_RXDMA_POLLRATE 1 /* RX DMA polling rate (us) */
#define DEFAULT_RXDMA_BUFSIZE 4096 /* RX DMA buffer size */
#define DEFAULT_RXDMA_TIMEOUT (3 * HZ)/* RX DMA timeout (jiffies) */
static struct omap_uart_port_info omap_serial_default_info[] __initdata = {
{
.dma_enabled = false,
.dma_rx_buf_size = DEFAULT_RXDMA_BUFSIZE,
.dma_rx_poll_rate = DEFAULT_RXDMA_POLLRATE,
.dma_rx_timeout = DEFAULT_RXDMA_TIMEOUT,
.autosuspend_timeout = DEFAULT_AUTOSUSPEND_DELAY,
},
};
#ifdef CONFIG_PM
static void omap_uart_enable_wakeup(struct device *dev, bool enable)
{
struct platform_device *pdev = to_platform_device(dev);
struct omap_device *od = to_omap_device(pdev);
if (!od)
return;
if (enable)
omap_hwmod_enable_wakeup(od->hwmods[0]);
else
omap_hwmod_disable_wakeup(od->hwmods[0]);
}
#else
static void omap_uart_enable_wakeup(struct device *dev, bool enable)
{}
#endif /* CONFIG_PM */
#ifdef CONFIG_OMAP_MUX
#define OMAP_UART_DEFAULT_PAD_NAME_LEN 28
static char rx_pad_name[OMAP_UART_DEFAULT_PAD_NAME_LEN],
tx_pad_name[OMAP_UART_DEFAULT_PAD_NAME_LEN] __initdata;
static void __init
omap_serial_fill_uart_tx_rx_pads(struct omap_board_data *bdata,
struct omap_uart_state *uart)
{
uart->default_omap_uart_pads[0].name = rx_pad_name;
uart->default_omap_uart_pads[0].flags = OMAP_DEVICE_PAD_REMUX |
OMAP_DEVICE_PAD_WAKEUP;
uart->default_omap_uart_pads[0].enable = OMAP_PIN_INPUT |
OMAP_MUX_MODE0;
uart->default_omap_uart_pads[0].idle = OMAP_PIN_INPUT | OMAP_MUX_MODE0;
uart->default_omap_uart_pads[1].name = tx_pad_name;
uart->default_omap_uart_pads[1].enable = OMAP_PIN_OUTPUT |
OMAP_MUX_MODE0;
bdata->pads = uart->default_omap_uart_pads;
bdata->pads_cnt = ARRAY_SIZE(uart->default_omap_uart_pads);
}
static void __init omap_serial_check_wakeup(struct omap_board_data *bdata,
struct omap_uart_state *uart)
{
struct omap_mux_partition *tx_partition = NULL, *rx_partition = NULL;
struct omap_mux *rx_mux = NULL, *tx_mux = NULL;
char *rx_fmt, *tx_fmt;
int uart_nr = bdata->id + 1;
if (bdata->id != 2) {
rx_fmt = "uart%d_rx.uart%d_rx";
tx_fmt = "uart%d_tx.uart%d_tx";
} else {
rx_fmt = "uart%d_rx_irrx.uart%d_rx_irrx";
tx_fmt = "uart%d_tx_irtx.uart%d_tx_irtx";
}
snprintf(rx_pad_name, OMAP_UART_DEFAULT_PAD_NAME_LEN, rx_fmt,
uart_nr, uart_nr);
snprintf(tx_pad_name, OMAP_UART_DEFAULT_PAD_NAME_LEN, tx_fmt,
uart_nr, uart_nr);
if (omap_mux_get_by_name(rx_pad_name, &rx_partition, &rx_mux) >= 0 &&
omap_mux_get_by_name
(tx_pad_name, &tx_partition, &tx_mux) >= 0) {
u16 tx_mode, rx_mode;
tx_mode = omap_mux_read(tx_partition, tx_mux->reg_offset);
rx_mode = omap_mux_read(rx_partition, rx_mux->reg_offset);
/*
* Check if uart is used in default tx/rx mode i.e. in mux mode0
* if yes then configure rx pin for wake up capability
*/
if (OMAP_MODE_UART(rx_mode) && OMAP_MODE_UART(tx_mode))
omap_serial_fill_uart_tx_rx_pads(bdata, uart);
}
}
#else
static void __init omap_serial_check_wakeup(struct omap_board_data *bdata,
struct omap_uart_state *uart)
{
}
#endif
static char *cmdline_find_option(char *str)
{
extern char *saved_command_line;
return strstr(saved_command_line, str);
}
static int __init omap_serial_early_init(void)
{
if (of_have_populated_dt())
return -ENODEV;
do {
char oh_name[MAX_UART_HWMOD_NAME_LEN];
struct omap_hwmod *oh;
struct omap_uart_state *uart;
char uart_name[MAX_UART_HWMOD_NAME_LEN];
snprintf(oh_name, MAX_UART_HWMOD_NAME_LEN,
"uart%d", num_uarts + 1);
oh = omap_hwmod_lookup(oh_name);
if (!oh)
break;
uart = kzalloc(sizeof(struct omap_uart_state), GFP_KERNEL);
if (WARN_ON(!uart))
return -ENODEV;
uart->oh = oh;
uart->num = num_uarts++;
list_add_tail(&uart->node, &uart_list);
snprintf(uart_name, MAX_UART_HWMOD_NAME_LEN,
"%s%d", OMAP_SERIAL_NAME, uart->num);
if (cmdline_find_option(uart_name)) {
console_uart_id = uart->num;
if (console_loglevel >= 10) {
uart_debug = true;
pr_info("%s used as console in debug mode: uart%d clocks will not be gated",
uart_name, uart->num);
}
}
} while (1);
return 0;
}
omap_core_initcall(omap_serial_early_init);
/**
* omap_serial_init_port() - initialize single serial port
* @bdata: port specific board data pointer
* @info: platform specific data pointer
*
* This function initialies serial driver for given port only.
* Platforms can call this function instead of omap_serial_init()
* if they don't plan to use all available UARTs as serial ports.
*
* Don't mix calls to omap_serial_init_port() and omap_serial_init(),
* use only one of the two.
*/
void __init omap_serial_init_port(struct omap_board_data *bdata,
struct omap_uart_port_info *info)
{
struct omap_uart_state *uart;
struct omap_hwmod *oh;
struct platform_device *pdev;
void *pdata = NULL;
u32 pdata_size = 0;
char *name;
struct omap_uart_port_info omap_up;
if (WARN_ON(!bdata))
return;
if (WARN_ON(bdata->id < 0))
return;
if (WARN_ON(bdata->id >= num_uarts))
return;
list_for_each_entry(uart, &uart_list, node)
if (bdata->id == uart->num)
break;
if (!info)
info = omap_serial_default_info;
oh = uart->oh;
name = DRIVER_NAME;
omap_up.dma_enabled = info->dma_enabled;
omap_up.uartclk = OMAP24XX_BASE_BAUD * 16;
omap_up.flags = UPF_BOOT_AUTOCONF;
omap_up.get_context_loss_count = omap_pm_get_dev_context_loss_count;
omap_up.enable_wakeup = omap_uart_enable_wakeup;
omap_up.dma_rx_buf_size = info->dma_rx_buf_size;
omap_up.dma_rx_timeout = info->dma_rx_timeout;
omap_up.dma_rx_poll_rate = info->dma_rx_poll_rate;
omap_up.autosuspend_timeout = info->autosuspend_timeout;
pdata = &omap_up;
pdata_size = sizeof(struct omap_uart_port_info);
if (WARN_ON(!oh))
return;
pdev = omap_device_build(name, uart->num, oh, pdata, pdata_size);
if (IS_ERR(pdev)) {
WARN(1, "Could not build omap_device for %s: %s.\n", name,
oh->name);
return;
}
oh->mux = omap_hwmod_mux_init(bdata->pads, bdata->pads_cnt);
if (console_uart_id == bdata->id) {
omap_device_enable(pdev);
pm_runtime_set_active(&pdev->dev);
}
oh->dev_attr = uart;
if (((cpu_is_omap34xx() || cpu_is_omap44xx()) && bdata->pads)
&& !uart_debug)
device_init_wakeup(&pdev->dev, true);
}
/**
* omap_serial_board_init() - initialize all supported serial ports
* @info: platform specific data pointer
*
* Initializes all available UARTs as serial ports. Platforms
* can call this function when they want to have default behaviour
* for serial ports (e.g initialize them all as serial ports).
*/
void __init omap_serial_board_init(struct omap_uart_port_info *info)
{
struct omap_uart_state *uart;
struct omap_board_data bdata;
list_for_each_entry(uart, &uart_list, node) {
bdata.id = uart->num;
bdata.flags = 0;
bdata.pads = NULL;
bdata.pads_cnt = 0;
omap_serial_check_wakeup(&bdata, uart);
if (!info)
omap_serial_init_port(&bdata, NULL);
else
omap_serial_init_port(&bdata, &info[uart->num]);
}
}
/**
* omap_serial_init() - initialize all supported serial ports
*
* Initializes all available UARTs.
* Platforms can call this function when they want to have default behaviour
* for serial ports (e.g initialize them all as serial ports).
*/
void __init omap_serial_init(void)
{
omap_serial_board_init(NULL);
}