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);
335 if (((cpu_is_omap34xx() || cpu_is_omap44xx()) && bdata->pads)
337 device_init_wakeup(&pdev->dev, true);
341 * omap_serial_board_init() - initialize all supported serial ports
342 * @info: platform specific data pointer
344 * Initializes all available UARTs as serial ports. Platforms
345 * can call this function when they want to have default behaviour
346 * for serial ports (e.g initialize them all as serial ports).
348 void __init omap_serial_board_init(struct omap_uart_port_info *info)
350 struct omap_uart_state *uart;
351 struct omap_board_data bdata;
353 list_for_each_entry(uart, &uart_list, node) {
354 bdata.id = uart->num;
359 omap_serial_check_wakeup(&bdata, uart);
362 omap_serial_init_port(&bdata, NULL);
364 omap_serial_init_port(&bdata, &info[uart->num]);
369 * omap_serial_init() - initialize all supported serial ports
371 * Initializes all available UARTs.
372 * Platforms can call this function when they want to have default behaviour
373 * for serial ports (e.g initialize them all as serial ports).
375 void __init omap_serial_init(void)
377 omap_serial_board_init(NULL);