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>
31 #include <plat-omap/dma-omap.h>
34 #include "omap_hwmod.h"
35 #include "omap_device.h"
38 #include "prm2xxx_3xxx.h"
40 #include "cm2xxx_3xxx.h"
41 #include "prm-regbits-34xx.h"
47 * NOTE: By default the serial auto_suspend timeout is disabled as it causes
48 * lost characters over the serial ports. This means that the UART clocks will
49 * stay on until power/autosuspend_delay is set for the uart from sysfs.
50 * This also causes that any deeper omap sleep states are blocked.
52 #define DEFAULT_AUTOSUSPEND_DELAY -1
54 #define MAX_UART_HWMOD_NAME_LEN 16
56 struct omap_uart_state
{
59 struct list_head node
;
60 struct omap_hwmod
*oh
;
61 struct omap_device_pad default_omap_uart_pads
[2];
64 static LIST_HEAD(uart_list
);
66 static u8 console_uart_id
= -1;
67 static u8 no_console_suspend
;
70 #define DEFAULT_RXDMA_POLLRATE 1 /* RX DMA polling rate (us) */
71 #define DEFAULT_RXDMA_BUFSIZE 4096 /* RX DMA buffer size */
72 #define DEFAULT_RXDMA_TIMEOUT (3 * HZ)/* RX DMA timeout (jiffies) */
74 static struct omap_uart_port_info omap_serial_default_info
[] __initdata
= {
77 .dma_rx_buf_size
= DEFAULT_RXDMA_BUFSIZE
,
78 .dma_rx_poll_rate
= DEFAULT_RXDMA_POLLRATE
,
79 .dma_rx_timeout
= DEFAULT_RXDMA_TIMEOUT
,
80 .autosuspend_timeout
= DEFAULT_AUTOSUSPEND_DELAY
,
85 static void omap_uart_enable_wakeup(struct device
*dev
, bool enable
)
87 struct platform_device
*pdev
= to_platform_device(dev
);
88 struct omap_device
*od
= to_omap_device(pdev
);
94 omap_hwmod_enable_wakeup(od
->hwmods
[0]);
96 omap_hwmod_disable_wakeup(od
->hwmods
[0]);
100 * Errata i291: [UART]:Cannot Acknowledge Idle Requests
101 * in Smartidle Mode When Configured for DMA Operations.
102 * WA: configure uart in force idle mode.
104 static void omap_uart_set_noidle(struct device
*dev
)
106 struct platform_device
*pdev
= to_platform_device(dev
);
107 struct omap_device
*od
= to_omap_device(pdev
);
109 omap_hwmod_set_slave_idlemode(od
->hwmods
[0], HWMOD_IDLEMODE_NO
);
112 static void omap_uart_set_smartidle(struct device
*dev
)
114 struct platform_device
*pdev
= to_platform_device(dev
);
115 struct omap_device
*od
= to_omap_device(pdev
);
118 if (od
->hwmods
[0]->class->sysc
->idlemodes
& SIDLE_SMART_WKUP
)
119 idlemode
= HWMOD_IDLEMODE_SMART_WKUP
;
121 idlemode
= HWMOD_IDLEMODE_SMART
;
123 omap_hwmod_set_slave_idlemode(od
->hwmods
[0], idlemode
);
127 static void omap_uart_enable_wakeup(struct device
*dev
, bool enable
)
129 static void omap_uart_set_noidle(struct device
*dev
) {}
130 static void omap_uart_set_smartidle(struct device
*dev
) {}
131 #endif /* CONFIG_PM */
133 #ifdef CONFIG_OMAP_MUX
135 #define OMAP_UART_DEFAULT_PAD_NAME_LEN 28
136 static char rx_pad_name
[OMAP_UART_DEFAULT_PAD_NAME_LEN
],
137 tx_pad_name
[OMAP_UART_DEFAULT_PAD_NAME_LEN
] __initdata
;
140 omap_serial_fill_uart_tx_rx_pads(struct omap_board_data
*bdata
,
141 struct omap_uart_state
*uart
)
143 uart
->default_omap_uart_pads
[0].name
= rx_pad_name
;
144 uart
->default_omap_uart_pads
[0].flags
= OMAP_DEVICE_PAD_REMUX
|
145 OMAP_DEVICE_PAD_WAKEUP
;
146 uart
->default_omap_uart_pads
[0].enable
= OMAP_PIN_INPUT
|
148 uart
->default_omap_uart_pads
[0].idle
= OMAP_PIN_INPUT
| OMAP_MUX_MODE0
;
149 uart
->default_omap_uart_pads
[1].name
= tx_pad_name
;
150 uart
->default_omap_uart_pads
[1].enable
= OMAP_PIN_OUTPUT
|
152 bdata
->pads
= uart
->default_omap_uart_pads
;
153 bdata
->pads_cnt
= ARRAY_SIZE(uart
->default_omap_uart_pads
);
156 static void __init
omap_serial_check_wakeup(struct omap_board_data
*bdata
,
157 struct omap_uart_state
*uart
)
159 struct omap_mux_partition
*tx_partition
= NULL
, *rx_partition
= NULL
;
160 struct omap_mux
*rx_mux
= NULL
, *tx_mux
= NULL
;
161 char *rx_fmt
, *tx_fmt
;
162 int uart_nr
= bdata
->id
+ 1;
164 if (bdata
->id
!= 2) {
165 rx_fmt
= "uart%d_rx.uart%d_rx";
166 tx_fmt
= "uart%d_tx.uart%d_tx";
168 rx_fmt
= "uart%d_rx_irrx.uart%d_rx_irrx";
169 tx_fmt
= "uart%d_tx_irtx.uart%d_tx_irtx";
172 snprintf(rx_pad_name
, OMAP_UART_DEFAULT_PAD_NAME_LEN
, rx_fmt
,
174 snprintf(tx_pad_name
, OMAP_UART_DEFAULT_PAD_NAME_LEN
, tx_fmt
,
177 if (omap_mux_get_by_name(rx_pad_name
, &rx_partition
, &rx_mux
) >= 0 &&
179 (tx_pad_name
, &tx_partition
, &tx_mux
) >= 0) {
180 u16 tx_mode
, rx_mode
;
182 tx_mode
= omap_mux_read(tx_partition
, tx_mux
->reg_offset
);
183 rx_mode
= omap_mux_read(rx_partition
, rx_mux
->reg_offset
);
186 * Check if uart is used in default tx/rx mode i.e. in mux mode0
187 * if yes then configure rx pin for wake up capability
189 if (OMAP_MODE_UART(rx_mode
) && OMAP_MODE_UART(tx_mode
))
190 omap_serial_fill_uart_tx_rx_pads(bdata
, uart
);
194 static void __init
omap_serial_check_wakeup(struct omap_board_data
*bdata
,
195 struct omap_uart_state
*uart
)
200 static char *cmdline_find_option(char *str
)
202 extern char *saved_command_line
;
204 return strstr(saved_command_line
, str
);
207 static int __init
omap_serial_early_init(void)
210 char oh_name
[MAX_UART_HWMOD_NAME_LEN
];
211 struct omap_hwmod
*oh
;
212 struct omap_uart_state
*uart
;
213 char uart_name
[MAX_UART_HWMOD_NAME_LEN
];
215 snprintf(oh_name
, MAX_UART_HWMOD_NAME_LEN
,
216 "uart%d", num_uarts
+ 1);
217 oh
= omap_hwmod_lookup(oh_name
);
221 uart
= kzalloc(sizeof(struct omap_uart_state
), GFP_KERNEL
);
226 uart
->num
= num_uarts
++;
227 list_add_tail(&uart
->node
, &uart_list
);
228 snprintf(uart_name
, MAX_UART_HWMOD_NAME_LEN
,
229 "%s%d", OMAP_SERIAL_NAME
, uart
->num
);
231 if (cmdline_find_option(uart_name
)) {
232 console_uart_id
= uart
->num
;
234 if (console_loglevel
>= 10) {
236 pr_info("%s used as console in debug mode: uart%d clocks will not be gated",
237 uart_name
, uart
->num
);
240 if (cmdline_find_option("no_console_suspend"))
241 no_console_suspend
= true;
244 * omap-uart can be used for earlyprintk logs
245 * So if omap-uart is used as console then prevent
246 * uart reset and idle to get logs from omap-uart
247 * until uart console driver is available to take
248 * care for console messages.
249 * Idling or resetting omap-uart while printing logs
250 * early boot logs can stall the boot-up.
252 oh
->flags
|= HWMOD_INIT_NO_IDLE
| HWMOD_INIT_NO_RESET
;
258 core_initcall(omap_serial_early_init
);
261 * omap_serial_init_port() - initialize single serial port
262 * @bdata: port specific board data pointer
263 * @info: platform specific data pointer
265 * This function initialies serial driver for given port only.
266 * Platforms can call this function instead of omap_serial_init()
267 * if they don't plan to use all available UARTs as serial ports.
269 * Don't mix calls to omap_serial_init_port() and omap_serial_init(),
270 * use only one of the two.
272 void __init
omap_serial_init_port(struct omap_board_data
*bdata
,
273 struct omap_uart_port_info
*info
)
275 struct omap_uart_state
*uart
;
276 struct omap_hwmod
*oh
;
277 struct platform_device
*pdev
;
281 struct omap_uart_port_info omap_up
;
285 if (WARN_ON(bdata
->id
< 0))
287 if (WARN_ON(bdata
->id
>= num_uarts
))
290 list_for_each_entry(uart
, &uart_list
, node
)
291 if (bdata
->id
== uart
->num
)
294 info
= omap_serial_default_info
;
299 omap_up
.dma_enabled
= info
->dma_enabled
;
300 omap_up
.uartclk
= OMAP24XX_BASE_BAUD
* 16;
301 omap_up
.flags
= UPF_BOOT_AUTOCONF
;
302 omap_up
.get_context_loss_count
= omap_pm_get_dev_context_loss_count
;
303 omap_up
.set_forceidle
= omap_uart_set_smartidle
;
304 omap_up
.set_noidle
= omap_uart_set_noidle
;
305 omap_up
.enable_wakeup
= omap_uart_enable_wakeup
;
306 omap_up
.dma_rx_buf_size
= info
->dma_rx_buf_size
;
307 omap_up
.dma_rx_timeout
= info
->dma_rx_timeout
;
308 omap_up
.dma_rx_poll_rate
= info
->dma_rx_poll_rate
;
309 omap_up
.autosuspend_timeout
= info
->autosuspend_timeout
;
310 omap_up
.DTR_gpio
= info
->DTR_gpio
;
311 omap_up
.DTR_inverted
= info
->DTR_inverted
;
312 omap_up
.DTR_present
= info
->DTR_present
;
315 pdata_size
= sizeof(struct omap_uart_port_info
);
320 pdev
= omap_device_build(name
, uart
->num
, oh
, pdata
, pdata_size
,
323 WARN(1, "Could not build omap_device for %s: %s.\n", name
,
328 if ((console_uart_id
== bdata
->id
) && no_console_suspend
)
329 omap_device_disable_idle_on_suspend(pdev
);
331 oh
->mux
= omap_hwmod_mux_init(bdata
->pads
, bdata
->pads_cnt
);
333 if (console_uart_id
== bdata
->id
) {
334 omap_device_enable(pdev
);
335 pm_runtime_set_active(&pdev
->dev
);
340 if (((cpu_is_omap34xx() || cpu_is_omap44xx()) && bdata
->pads
)
342 device_init_wakeup(&pdev
->dev
, true);
346 * omap_serial_board_init() - initialize all supported serial ports
347 * @info: platform specific data pointer
349 * Initializes all available UARTs as serial ports. Platforms
350 * can call this function when they want to have default behaviour
351 * for serial ports (e.g initialize them all as serial ports).
353 void __init
omap_serial_board_init(struct omap_uart_port_info
*info
)
355 struct omap_uart_state
*uart
;
356 struct omap_board_data bdata
;
358 list_for_each_entry(uart
, &uart_list
, node
) {
359 bdata
.id
= uart
->num
;
364 omap_serial_check_wakeup(&bdata
, uart
);
367 omap_serial_init_port(&bdata
, NULL
);
369 omap_serial_init_port(&bdata
, &info
[uart
->num
]);
374 * omap_serial_init() - initialize all supported serial ports
376 * Initializes all available UARTs.
377 * Platforms can call this function when they want to have default behaviour
378 * for serial ports (e.g initialize them all as serial ports).
380 void __init
omap_serial_init(void)
382 omap_serial_board_init(NULL
);