2 * arch/arm/mach-omap2/serial.c
4 * OMAP2 serial support.
6 * Copyright (C) 2005-2008 Nokia Corporation
7 * Author: Paul Mundt <paul.mundt@nokia.com>
9 * Major rework for PM support by Kevin Hilman
11 * Based off of arch/arm/mach-omap/omap1/serial.c
13 * Copyright (C) 2009 Texas Instruments
14 * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com
16 * This file is subject to the terms and conditions of the GNU General Public
17 * License. See the file "COPYING" in the main directory of this archive
20 #include <linux/kernel.h>
21 #include <linux/init.h>
22 #include <linux/clk.h>
24 #include <linux/delay.h>
25 #include <linux/platform_device.h>
26 #include <linux/slab.h>
27 #include <linux/pm_runtime.h>
28 #include <linux/console.h>
30 #include <plat/omap-serial.h>
33 #include <plat/omap_hwmod.h>
34 #include <plat/omap_device.h>
35 #include <plat/omap-pm.h>
36 #include <plat/serial.h>
38 #include "prm2xxx_3xxx.h"
40 #include "cm2xxx_3xxx.h"
41 #include "prm-regbits-34xx.h"
46 * NOTE: By default the serial auto_suspend timeout is disabled as it causes
47 * lost characters over the serial ports. This means that the UART clocks will
48 * stay on until power/autosuspend_delay is set for the uart from sysfs.
49 * This also causes that any deeper omap sleep states are blocked.
51 #define DEFAULT_AUTOSUSPEND_DELAY -1
53 #define MAX_UART_HWMOD_NAME_LEN 16
55 struct omap_uart_state
{
58 struct list_head node
;
59 struct omap_hwmod
*oh
;
60 struct omap_device_pad default_omap_uart_pads
[2];
63 static LIST_HEAD(uart_list
);
65 static u8 console_uart_id
= -1;
66 static u8 no_console_suspend
;
69 #define DEFAULT_RXDMA_POLLRATE 1 /* RX DMA polling rate (us) */
70 #define DEFAULT_RXDMA_BUFSIZE 4096 /* RX DMA buffer size */
71 #define DEFAULT_RXDMA_TIMEOUT (3 * HZ)/* RX DMA timeout (jiffies) */
73 static struct omap_uart_port_info omap_serial_default_info
[] __initdata
= {
76 .dma_rx_buf_size
= DEFAULT_RXDMA_BUFSIZE
,
77 .dma_rx_poll_rate
= DEFAULT_RXDMA_POLLRATE
,
78 .dma_rx_timeout
= DEFAULT_RXDMA_TIMEOUT
,
79 .autosuspend_timeout
= DEFAULT_AUTOSUSPEND_DELAY
,
84 static void omap_uart_enable_wakeup(struct device
*dev
, bool enable
)
86 struct platform_device
*pdev
= to_platform_device(dev
);
87 struct omap_device
*od
= to_omap_device(pdev
);
93 omap_hwmod_enable_wakeup(od
->hwmods
[0]);
95 omap_hwmod_disable_wakeup(od
->hwmods
[0]);
99 * Errata i291: [UART]:Cannot Acknowledge Idle Requests
100 * in Smartidle Mode When Configured for DMA Operations.
101 * WA: configure uart in force idle mode.
103 static void omap_uart_set_noidle(struct device
*dev
)
105 struct platform_device
*pdev
= to_platform_device(dev
);
106 struct omap_device
*od
= to_omap_device(pdev
);
108 omap_hwmod_set_slave_idlemode(od
->hwmods
[0], HWMOD_IDLEMODE_NO
);
111 static void omap_uart_set_smartidle(struct device
*dev
)
113 struct platform_device
*pdev
= to_platform_device(dev
);
114 struct omap_device
*od
= to_omap_device(pdev
);
117 if (od
->hwmods
[0]->class->sysc
->idlemodes
& SIDLE_SMART_WKUP
)
118 idlemode
= HWMOD_IDLEMODE_SMART_WKUP
;
120 idlemode
= HWMOD_IDLEMODE_SMART
;
122 omap_hwmod_set_slave_idlemode(od
->hwmods
[0], idlemode
);
126 static void omap_uart_enable_wakeup(struct device
*dev
, bool enable
)
128 static void omap_uart_set_noidle(struct device
*dev
) {}
129 static void omap_uart_set_smartidle(struct device
*dev
) {}
130 #endif /* CONFIG_PM */
132 #ifdef CONFIG_OMAP_MUX
134 #define OMAP_UART_DEFAULT_PAD_NAME_LEN 28
135 static char rx_pad_name
[OMAP_UART_DEFAULT_PAD_NAME_LEN
],
136 tx_pad_name
[OMAP_UART_DEFAULT_PAD_NAME_LEN
] __initdata
;
139 omap_serial_fill_uart_tx_rx_pads(struct omap_board_data
*bdata
,
140 struct omap_uart_state
*uart
)
142 uart
->default_omap_uart_pads
[0].name
= rx_pad_name
;
143 uart
->default_omap_uart_pads
[0].flags
= OMAP_DEVICE_PAD_REMUX
|
144 OMAP_DEVICE_PAD_WAKEUP
;
145 uart
->default_omap_uart_pads
[0].enable
= OMAP_PIN_INPUT
|
147 uart
->default_omap_uart_pads
[0].idle
= OMAP_PIN_INPUT
| OMAP_MUX_MODE0
;
148 uart
->default_omap_uart_pads
[1].name
= tx_pad_name
;
149 uart
->default_omap_uart_pads
[1].enable
= OMAP_PIN_OUTPUT
|
151 bdata
->pads
= uart
->default_omap_uart_pads
;
152 bdata
->pads_cnt
= ARRAY_SIZE(uart
->default_omap_uart_pads
);
155 static void __init
omap_serial_check_wakeup(struct omap_board_data
*bdata
,
156 struct omap_uart_state
*uart
)
158 struct omap_mux_partition
*tx_partition
= NULL
, *rx_partition
= NULL
;
159 struct omap_mux
*rx_mux
= NULL
, *tx_mux
= NULL
;
160 char *rx_fmt
, *tx_fmt
;
161 int uart_nr
= bdata
->id
+ 1;
163 if (bdata
->id
!= 2) {
164 rx_fmt
= "uart%d_rx.uart%d_rx";
165 tx_fmt
= "uart%d_tx.uart%d_tx";
167 rx_fmt
= "uart%d_rx_irrx.uart%d_rx_irrx";
168 tx_fmt
= "uart%d_tx_irtx.uart%d_tx_irtx";
171 snprintf(rx_pad_name
, OMAP_UART_DEFAULT_PAD_NAME_LEN
, rx_fmt
,
173 snprintf(tx_pad_name
, OMAP_UART_DEFAULT_PAD_NAME_LEN
, tx_fmt
,
176 if (omap_mux_get_by_name(rx_pad_name
, &rx_partition
, &rx_mux
) >= 0 &&
178 (tx_pad_name
, &tx_partition
, &tx_mux
) >= 0) {
179 u16 tx_mode
, rx_mode
;
181 tx_mode
= omap_mux_read(tx_partition
, tx_mux
->reg_offset
);
182 rx_mode
= omap_mux_read(rx_partition
, rx_mux
->reg_offset
);
185 * Check if uart is used in default tx/rx mode i.e. in mux mode0
186 * if yes then configure rx pin for wake up capability
188 if (OMAP_MODE_UART(rx_mode
) && OMAP_MODE_UART(tx_mode
))
189 omap_serial_fill_uart_tx_rx_pads(bdata
, uart
);
193 static void __init
omap_serial_check_wakeup(struct omap_board_data
*bdata
,
194 struct omap_uart_state
*uart
)
199 static char *cmdline_find_option(char *str
)
201 extern char *saved_command_line
;
203 return strstr(saved_command_line
, str
);
206 static int __init
omap_serial_early_init(void)
209 char oh_name
[MAX_UART_HWMOD_NAME_LEN
];
210 struct omap_hwmod
*oh
;
211 struct omap_uart_state
*uart
;
212 char uart_name
[MAX_UART_HWMOD_NAME_LEN
];
214 snprintf(oh_name
, MAX_UART_HWMOD_NAME_LEN
,
215 "uart%d", num_uarts
+ 1);
216 oh
= omap_hwmod_lookup(oh_name
);
220 uart
= kzalloc(sizeof(struct omap_uart_state
), GFP_KERNEL
);
225 uart
->num
= num_uarts
++;
226 list_add_tail(&uart
->node
, &uart_list
);
227 snprintf(uart_name
, MAX_UART_HWMOD_NAME_LEN
,
228 "%s%d", OMAP_SERIAL_NAME
, uart
->num
);
230 if (cmdline_find_option(uart_name
)) {
231 console_uart_id
= uart
->num
;
233 if (console_loglevel
>= 10) {
235 pr_info("%s used as console in debug mode: uart%d clocks will not be gated",
236 uart_name
, uart
->num
);
239 if (cmdline_find_option("no_console_suspend"))
240 no_console_suspend
= true;
243 * omap-uart can be used for earlyprintk logs
244 * So if omap-uart is used as console then prevent
245 * uart reset and idle to get logs from omap-uart
246 * until uart console driver is available to take
247 * care for console messages.
248 * Idling or resetting omap-uart while printing logs
249 * early boot logs can stall the boot-up.
251 oh
->flags
|= HWMOD_INIT_NO_IDLE
| HWMOD_INIT_NO_RESET
;
257 core_initcall(omap_serial_early_init
);
260 * omap_serial_init_port() - initialize single serial port
261 * @bdata: port specific board data pointer
262 * @info: platform specific data pointer
264 * This function initialies serial driver for given port only.
265 * Platforms can call this function instead of omap_serial_init()
266 * if they don't plan to use all available UARTs as serial ports.
268 * Don't mix calls to omap_serial_init_port() and omap_serial_init(),
269 * use only one of the two.
271 void __init
omap_serial_init_port(struct omap_board_data
*bdata
,
272 struct omap_uart_port_info
*info
)
274 struct omap_uart_state
*uart
;
275 struct omap_hwmod
*oh
;
276 struct platform_device
*pdev
;
280 struct omap_uart_port_info omap_up
;
284 if (WARN_ON(bdata
->id
< 0))
286 if (WARN_ON(bdata
->id
>= num_uarts
))
289 list_for_each_entry(uart
, &uart_list
, node
)
290 if (bdata
->id
== uart
->num
)
293 info
= omap_serial_default_info
;
298 omap_up
.dma_enabled
= info
->dma_enabled
;
299 omap_up
.uartclk
= OMAP24XX_BASE_BAUD
* 16;
300 omap_up
.flags
= UPF_BOOT_AUTOCONF
;
301 omap_up
.get_context_loss_count
= omap_pm_get_dev_context_loss_count
;
302 omap_up
.set_forceidle
= omap_uart_set_smartidle
;
303 omap_up
.set_noidle
= omap_uart_set_noidle
;
304 omap_up
.enable_wakeup
= omap_uart_enable_wakeup
;
305 omap_up
.dma_rx_buf_size
= info
->dma_rx_buf_size
;
306 omap_up
.dma_rx_timeout
= info
->dma_rx_timeout
;
307 omap_up
.dma_rx_poll_rate
= info
->dma_rx_poll_rate
;
308 omap_up
.autosuspend_timeout
= info
->autosuspend_timeout
;
309 omap_up
.DTR_gpio
= info
->DTR_gpio
;
310 omap_up
.DTR_inverted
= info
->DTR_inverted
;
311 omap_up
.DTR_present
= info
->DTR_present
;
314 pdata_size
= sizeof(struct omap_uart_port_info
);
319 pdev
= omap_device_build(name
, uart
->num
, oh
, pdata
, pdata_size
,
322 WARN(1, "Could not build omap_device for %s: %s.\n", name
,
327 if ((console_uart_id
== bdata
->id
) && no_console_suspend
)
328 omap_device_disable_idle_on_suspend(pdev
);
330 oh
->mux
= omap_hwmod_mux_init(bdata
->pads
, bdata
->pads_cnt
);
334 if (((cpu_is_omap34xx() || cpu_is_omap44xx()) && bdata
->pads
)
336 device_init_wakeup(&pdev
->dev
, true);
340 * omap_serial_board_init() - initialize all supported serial ports
341 * @info: platform specific data pointer
343 * Initializes all available UARTs as serial ports. Platforms
344 * can call this function when they want to have default behaviour
345 * for serial ports (e.g initialize them all as serial ports).
347 void __init
omap_serial_board_init(struct omap_uart_port_info
*info
)
349 struct omap_uart_state
*uart
;
350 struct omap_board_data bdata
;
352 list_for_each_entry(uart
, &uart_list
, node
) {
353 bdata
.id
= uart
->num
;
358 omap_serial_check_wakeup(&bdata
, uart
);
361 omap_serial_init_port(&bdata
, NULL
);
363 omap_serial_init_port(&bdata
, &info
[uart
->num
]);
368 * omap_serial_init() - initialize all supported serial ports
370 * Initializes all available UARTs.
371 * Platforms can call this function when they want to have default behaviour
372 * for serial ports (e.g initialize them all as serial ports).
374 void __init
omap_serial_init(void)
376 omap_serial_board_init(NULL
);