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Linux 2.6.31.8
[linux/fpc-iii.git] / arch / arm / mach-omap2 / serial.c
bloba7421a50410bc16a23126439071c73f51b35474e
1 /*
2 * arch/arm/mach-omap2/serial.c
3 *
4 * OMAP2 serial support.
5 *
6 * Copyright (C) 2005-2008 Nokia Corporation
7 * Author: Paul Mundt <paul.mundt@nokia.com>
8 *
9 * Major rework for PM support by Kevin Hilman
10 *
11 * Based off of arch/arm/mach-omap/omap1/serial.c
12 *
13 * Copyright (C) 2009 Texas Instruments
14 * Added OMAP4 support - Santosh Shilimkar <santosh.shilimkar@ti.com
15 *
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
18 * for more details.
19 */
20 #include <linux/kernel.h>
21 #include <linux/init.h>
22 #include <linux/serial_8250.h>
23 #include <linux/serial_reg.h>
24 #include <linux/clk.h>
25 #include <linux/io.h>
26
27 #include <mach/common.h>
28 #include <mach/board.h>
29 #include <mach/clock.h>
30 #include <mach/control.h>
31
32 #include "prm.h"
33 #include "pm.h"
34 #include "prm-regbits-34xx.h"
35
36 #define UART_OMAP_WER 0x17 /* Wake-up enable register */
37
38 #define DEFAULT_TIMEOUT (5 * HZ)
39
40 struct omap_uart_state {
41 int num;
42 int can_sleep;
43 struct timer_list timer;
44 u32 timeout;
45
46 void __iomem *wk_st;
47 void __iomem *wk_en;
48 u32 wk_mask;
49 u32 padconf;
50
51 struct clk *ick;
52 struct clk *fck;
53 int clocked;
54
55 struct plat_serial8250_port *p;
56 struct list_head node;
57 struct platform_device pdev;
58
59 #if defined(CONFIG_ARCH_OMAP3) && defined(CONFIG_PM)
60 int context_valid;
61
62 /* Registers to be saved/restored for OFF-mode */
63 u16 dll;
64 u16 dlh;
65 u16 ier;
66 u16 sysc;
67 u16 scr;
68 u16 wer;
69 #endif
70 };
71
72 static LIST_HEAD(uart_list);
73
74 static struct plat_serial8250_port serial_platform_data0[] = {
75 {
76 .membase = IO_ADDRESS(OMAP_UART1_BASE),
77 .mapbase = OMAP_UART1_BASE,
78 .irq = 72,
79 .flags = UPF_BOOT_AUTOCONF,
80 .iotype = UPIO_MEM,
81 .regshift = 2,
82 .uartclk = OMAP24XX_BASE_BAUD * 16,
83 }, {
84 .flags = 0
85 }
86 };
87
88 static struct plat_serial8250_port serial_platform_data1[] = {
89 {
90 .membase = IO_ADDRESS(OMAP_UART2_BASE),
91 .mapbase = OMAP_UART2_BASE,
92 .irq = 73,
93 .flags = UPF_BOOT_AUTOCONF,
94 .iotype = UPIO_MEM,
95 .regshift = 2,
96 .uartclk = OMAP24XX_BASE_BAUD * 16,
97 }, {
98 .flags = 0
99 }
100 };
101
102 static struct plat_serial8250_port serial_platform_data2[] = {
103 {
104 .membase = IO_ADDRESS(OMAP_UART3_BASE),
105 .mapbase = OMAP_UART3_BASE,
106 .irq = 74,
107 .flags = UPF_BOOT_AUTOCONF,
108 .iotype = UPIO_MEM,
109 .regshift = 2,
110 .uartclk = OMAP24XX_BASE_BAUD * 16,
111 }, {
112 .flags = 0
113 }
114 };
115
116 static inline unsigned int serial_read_reg(struct plat_serial8250_port *up,
117 int offset)
118 {
119 offset <<= up->regshift;
120 return (unsigned int)__raw_readb(up->membase + offset);
121 }
122
123 static inline void serial_write_reg(struct plat_serial8250_port *p, int offset,
124 int value)
125 {
126 offset <<= p->regshift;
127 __raw_writeb(value, p->membase + offset);
128 }
129
130 /*
131 * Internal UARTs need to be initialized for the 8250 autoconfig to work
132 * properly. Note that the TX watermark initialization may not be needed
133 * once the 8250.c watermark handling code is merged.
134 */
135 static inline void __init omap_uart_reset(struct omap_uart_state *uart)
136 {
137 struct plat_serial8250_port *p = uart->p;
138
139 serial_write_reg(p, UART_OMAP_MDR1, 0x07);
140 serial_write_reg(p, UART_OMAP_SCR, 0x08);
141 serial_write_reg(p, UART_OMAP_MDR1, 0x00);
142 serial_write_reg(p, UART_OMAP_SYSC, (0x02 << 3) | (1 << 2) | (1 << 0));
143 }
144
145 #if defined(CONFIG_PM) && defined(CONFIG_ARCH_OMAP3)
146
147 static int enable_off_mode; /* to be removed by full off-mode patches */
148
149 static void omap_uart_save_context(struct omap_uart_state *uart)
150 {
151 u16 lcr = 0;
152 struct plat_serial8250_port *p = uart->p;
153
154 if (!enable_off_mode)
155 return;
156
157 lcr = serial_read_reg(p, UART_LCR);
158 serial_write_reg(p, UART_LCR, 0xBF);
159 uart->dll = serial_read_reg(p, UART_DLL);
160 uart->dlh = serial_read_reg(p, UART_DLM);
161 serial_write_reg(p, UART_LCR, lcr);
162 uart->ier = serial_read_reg(p, UART_IER);
163 uart->sysc = serial_read_reg(p, UART_OMAP_SYSC);
164 uart->scr = serial_read_reg(p, UART_OMAP_SCR);
165 uart->wer = serial_read_reg(p, UART_OMAP_WER);
166
167 uart->context_valid = 1;
168 }
169
170 static void omap_uart_restore_context(struct omap_uart_state *uart)
171 {
172 u16 efr = 0;
173 struct plat_serial8250_port *p = uart->p;
174
175 if (!enable_off_mode)
176 return;
177
178 if (!uart->context_valid)
179 return;
180
181 uart->context_valid = 0;
182
183 serial_write_reg(p, UART_OMAP_MDR1, 0x7);
184 serial_write_reg(p, UART_LCR, 0xBF); /* Config B mode */
185 efr = serial_read_reg(p, UART_EFR);
186 serial_write_reg(p, UART_EFR, UART_EFR_ECB);
187 serial_write_reg(p, UART_LCR, 0x0); /* Operational mode */
188 serial_write_reg(p, UART_IER, 0x0);
189 serial_write_reg(p, UART_LCR, 0xBF); /* Config B mode */
190 serial_write_reg(p, UART_DLL, uart->dll);
191 serial_write_reg(p, UART_DLM, uart->dlh);
192 serial_write_reg(p, UART_LCR, 0x0); /* Operational mode */
193 serial_write_reg(p, UART_IER, uart->ier);
194 serial_write_reg(p, UART_FCR, 0xA1);
195 serial_write_reg(p, UART_LCR, 0xBF); /* Config B mode */
196 serial_write_reg(p, UART_EFR, efr);
197 serial_write_reg(p, UART_LCR, UART_LCR_WLEN8);
198 serial_write_reg(p, UART_OMAP_SCR, uart->scr);
199 serial_write_reg(p, UART_OMAP_WER, uart->wer);
200 serial_write_reg(p, UART_OMAP_SYSC, uart->sysc);
201 serial_write_reg(p, UART_OMAP_MDR1, 0x00); /* UART 16x mode */
202 }
203 #else
204 static inline void omap_uart_save_context(struct omap_uart_state *uart) {}
205 static inline void omap_uart_restore_context(struct omap_uart_state *uart) {}
206 #endif /* CONFIG_PM && CONFIG_ARCH_OMAP3 */
207
208 static inline void omap_uart_enable_clocks(struct omap_uart_state *uart)
209 {
210 if (uart->clocked)
211 return;
212
213 clk_enable(uart->ick);
214 clk_enable(uart->fck);
215 uart->clocked = 1;
216 omap_uart_restore_context(uart);
217 }
218
219 #ifdef CONFIG_PM
220
221 static inline void omap_uart_disable_clocks(struct omap_uart_state *uart)
222 {
223 if (!uart->clocked)
224 return;
225
226 omap_uart_save_context(uart);
227 uart->clocked = 0;
228 clk_disable(uart->ick);
229 clk_disable(uart->fck);
230 }
231
232 static void omap_uart_enable_wakeup(struct omap_uart_state *uart)
233 {
234 /* Set wake-enable bit */
235 if (uart->wk_en && uart->wk_mask) {
236 u32 v = __raw_readl(uart->wk_en);
237 v |= uart->wk_mask;
238 __raw_writel(v, uart->wk_en);
239 }
240
241 /* Ensure IOPAD wake-enables are set */
242 if (cpu_is_omap34xx() && uart->padconf) {
243 u16 v = omap_ctrl_readw(uart->padconf);
244 v |= OMAP3_PADCONF_WAKEUPENABLE0;
245 omap_ctrl_writew(v, uart->padconf);
246 }
247 }
248
249 static void omap_uart_disable_wakeup(struct omap_uart_state *uart)
250 {
251 /* Clear wake-enable bit */
252 if (uart->wk_en && uart->wk_mask) {
253 u32 v = __raw_readl(uart->wk_en);
254 v &= ~uart->wk_mask;
255 __raw_writel(v, uart->wk_en);
256 }
257
258 /* Ensure IOPAD wake-enables are cleared */
259 if (cpu_is_omap34xx() && uart->padconf) {
260 u16 v = omap_ctrl_readw(uart->padconf);
261 v &= ~OMAP3_PADCONF_WAKEUPENABLE0;
262 omap_ctrl_writew(v, uart->padconf);
263 }
264 }
265
266 static void omap_uart_smart_idle_enable(struct omap_uart_state *uart,
267 int enable)
268 {
269 struct plat_serial8250_port *p = uart->p;
270 u16 sysc;
271
272 sysc = serial_read_reg(p, UART_OMAP_SYSC) & 0x7;
273 if (enable)
274 sysc |= 0x2 << 3;
275 else
276 sysc |= 0x1 << 3;
277
278 serial_write_reg(p, UART_OMAP_SYSC, sysc);
279 }
280
281 static void omap_uart_block_sleep(struct omap_uart_state *uart)
282 {
283 omap_uart_enable_clocks(uart);
284
285 omap_uart_smart_idle_enable(uart, 0);
286 uart->can_sleep = 0;
287 if (uart->timeout)
288 mod_timer(&uart->timer, jiffies + uart->timeout);
289 else
290 del_timer(&uart->timer);
291 }
292
293 static void omap_uart_allow_sleep(struct omap_uart_state *uart)
294 {
295 if (device_may_wakeup(&uart->pdev.dev))
296 omap_uart_enable_wakeup(uart);
297 else
298 omap_uart_disable_wakeup(uart);
299
300 if (!uart->clocked)
301 return;
302
303 omap_uart_smart_idle_enable(uart, 1);
304 uart->can_sleep = 1;
305 del_timer(&uart->timer);
306 }
307
308 static void omap_uart_idle_timer(unsigned long data)
309 {
310 struct omap_uart_state *uart = (struct omap_uart_state *)data;
311
312 omap_uart_allow_sleep(uart);
313 }
314
315 void omap_uart_prepare_idle(int num)
316 {
317 struct omap_uart_state *uart;
318
319 list_for_each_entry(uart, &uart_list, node) {
320 if (num == uart->num && uart->can_sleep) {
321 omap_uart_disable_clocks(uart);
322 return;
323 }
324 }
325 }
326
327 void omap_uart_resume_idle(int num)
328 {
329 struct omap_uart_state *uart;
330
331 list_for_each_entry(uart, &uart_list, node) {
332 if (num == uart->num) {
333 omap_uart_enable_clocks(uart);
334
335 /* Check for IO pad wakeup */
336 if (cpu_is_omap34xx() && uart->padconf) {
337 u16 p = omap_ctrl_readw(uart->padconf);
338
339 if (p & OMAP3_PADCONF_WAKEUPEVENT0)
340 omap_uart_block_sleep(uart);
341 }
342
343 /* Check for normal UART wakeup */
344 if (__raw_readl(uart->wk_st) & uart->wk_mask)
345 omap_uart_block_sleep(uart);
346 return;
347 }
348 }
349 }
350
351 void omap_uart_prepare_suspend(void)
352 {
353 struct omap_uart_state *uart;
354
355 list_for_each_entry(uart, &uart_list, node) {
356 omap_uart_allow_sleep(uart);
357 }
358 }
359
360 int omap_uart_can_sleep(void)
361 {
362 struct omap_uart_state *uart;
363 int can_sleep = 1;
364
365 list_for_each_entry(uart, &uart_list, node) {
366 if (!uart->clocked)
367 continue;
368
369 if (!uart->can_sleep) {
370 can_sleep = 0;
371 continue;
372 }
373
374 /* This UART can now safely sleep. */
375 omap_uart_allow_sleep(uart);
376 }
377
378 return can_sleep;
379 }
380
381 /**
382 * omap_uart_interrupt()
383 *
384 * This handler is used only to detect that *any* UART interrupt has
385 * occurred. It does _nothing_ to handle the interrupt. Rather,
386 * any UART interrupt will trigger the inactivity timer so the
387 * UART will not idle or sleep for its timeout period.
388 *
389 **/
390 static irqreturn_t omap_uart_interrupt(int irq, void *dev_id)
391 {
392 struct omap_uart_state *uart = dev_id;
393
394 omap_uart_block_sleep(uart);
395
396 return IRQ_NONE;
397 }
398
399 static void omap_uart_idle_init(struct omap_uart_state *uart)
400 {
401 struct plat_serial8250_port *p = uart->p;
402 int ret;
403
404 uart->can_sleep = 0;
405 uart->timeout = DEFAULT_TIMEOUT;
406 setup_timer(&uart->timer, omap_uart_idle_timer,
407 (unsigned long) uart);
408 mod_timer(&uart->timer, jiffies + uart->timeout);
409 omap_uart_smart_idle_enable(uart, 0);
410
411 if (cpu_is_omap34xx()) {
412 u32 mod = (uart->num == 2) ? OMAP3430_PER_MOD : CORE_MOD;
413 u32 wk_mask = 0;
414 u32 padconf = 0;
415
416 uart->wk_en = OMAP34XX_PRM_REGADDR(mod, PM_WKEN1);
417 uart->wk_st = OMAP34XX_PRM_REGADDR(mod, PM_WKST1);
418 switch (uart->num) {
419 case 0:
420 wk_mask = OMAP3430_ST_UART1_MASK;
421 padconf = 0x182;
422 break;
423 case 1:
424 wk_mask = OMAP3430_ST_UART2_MASK;
425 padconf = 0x17a;
426 break;
427 case 2:
428 wk_mask = OMAP3430_ST_UART3_MASK;
429 padconf = 0x19e;
430 break;
431 }
432 uart->wk_mask = wk_mask;
433 uart->padconf = padconf;
434 } else if (cpu_is_omap24xx()) {
435 u32 wk_mask = 0;
436
437 if (cpu_is_omap2430()) {
438 uart->wk_en = OMAP2430_PRM_REGADDR(CORE_MOD, PM_WKEN1);
439 uart->wk_st = OMAP2430_PRM_REGADDR(CORE_MOD, PM_WKST1);
440 } else if (cpu_is_omap2420()) {
441 uart->wk_en = OMAP2420_PRM_REGADDR(CORE_MOD, PM_WKEN1);
442 uart->wk_st = OMAP2420_PRM_REGADDR(CORE_MOD, PM_WKST1);
443 }
444 switch (uart->num) {
445 case 0:
446 wk_mask = OMAP24XX_ST_UART1_MASK;
447 break;
448 case 1:
449 wk_mask = OMAP24XX_ST_UART2_MASK;
450 break;
451 case 2:
452 wk_mask = OMAP24XX_ST_UART3_MASK;
453 break;
454 }
455 uart->wk_mask = wk_mask;
456 } else {
457 uart->wk_en = 0;
458 uart->wk_st = 0;
459 uart->wk_mask = 0;
460 uart->padconf = 0;
461 }
462
463 p->flags |= UPF_SHARE_IRQ;
464 ret = request_irq(p->irq, omap_uart_interrupt, IRQF_SHARED,
465 "serial idle", (void *)uart);
466 WARN_ON(ret);
467 }
468
469 void omap_uart_enable_irqs(int enable)
470 {
471 int ret;
472 struct omap_uart_state *uart;
473
474 list_for_each_entry(uart, &uart_list, node) {
475 if (enable)
476 ret = request_irq(uart->p->irq, omap_uart_interrupt,
477 IRQF_SHARED, "serial idle", (void *)uart);
478 else
479 free_irq(uart->p->irq, (void *)uart);
480 }
481 }
482
483 static ssize_t sleep_timeout_show(struct device *dev,
484 struct device_attribute *attr,
485 char *buf)
486 {
487 struct platform_device *pdev = container_of(dev,
488 struct platform_device, dev);
489 struct omap_uart_state *uart = container_of(pdev,
490 struct omap_uart_state, pdev);
491
492 return sprintf(buf, "%u\n", uart->timeout / HZ);
493 }
494
495 static ssize_t sleep_timeout_store(struct device *dev,
496 struct device_attribute *attr,
497 const char *buf, size_t n)
498 {
499 struct platform_device *pdev = container_of(dev,
500 struct platform_device, dev);
501 struct omap_uart_state *uart = container_of(pdev,
502 struct omap_uart_state, pdev);
503 unsigned int value;
504
505 if (sscanf(buf, "%u", &value) != 1) {
506 printk(KERN_ERR "sleep_timeout_store: Invalid value\n");
507 return -EINVAL;
508 }
509
510 uart->timeout = value * HZ;
511 if (uart->timeout)
512 mod_timer(&uart->timer, jiffies + uart->timeout);
513 else
514 /* A zero value means disable timeout feature */
515 omap_uart_block_sleep(uart);
516
517 return n;
518 }
519
520 DEVICE_ATTR(sleep_timeout, 0644, sleep_timeout_show, sleep_timeout_store);
521 #define DEV_CREATE_FILE(dev, attr) WARN_ON(device_create_file(dev, attr))
522 #else
523 static inline void omap_uart_idle_init(struct omap_uart_state *uart) {}
524 #define DEV_CREATE_FILE(dev, attr)
525 #endif /* CONFIG_PM */
526
527 static struct omap_uart_state omap_uart[OMAP_MAX_NR_PORTS] = {
528 {
529 .pdev = {
530 .name = "serial8250",
531 .id = PLAT8250_DEV_PLATFORM,
532 .dev = {
533 .platform_data = serial_platform_data0,
534 },
535 },
536 }, {
537 .pdev = {
538 .name = "serial8250",
539 .id = PLAT8250_DEV_PLATFORM1,
540 .dev = {
541 .platform_data = serial_platform_data1,
542 },
543 },
544 }, {
545 .pdev = {
546 .name = "serial8250",
547 .id = PLAT8250_DEV_PLATFORM2,
548 .dev = {
549 .platform_data = serial_platform_data2,
550 },
551 },
552 },
553 };
554
555 void __init omap_serial_init(void)
556 {
557 int i;
558 const struct omap_uart_config *info;
559 char name[16];
560
561 /*
562 * Make sure the serial ports are muxed on at this point.
563 * You have to mux them off in device drivers later on
564 * if not needed.
565 */
566
567 info = omap_get_config(OMAP_TAG_UART, struct omap_uart_config);
568
569 if (info == NULL)
570 return;
571
572 for (i = 0; i < OMAP_MAX_NR_PORTS; i++) {
573 struct omap_uart_state *uart = &omap_uart[i];
574 struct platform_device *pdev = &uart->pdev;
575 struct device *dev = &pdev->dev;
576 struct plat_serial8250_port *p = dev->platform_data;
577
578 if (!(info->enabled_uarts & (1 << i))) {
579 p->membase = NULL;
580 p->mapbase = 0;
581 continue;
582 }
583
584 sprintf(name, "uart%d_ick", i+1);
585 uart->ick = clk_get(NULL, name);
586 if (IS_ERR(uart->ick)) {
587 printk(KERN_ERR "Could not get uart%d_ick\n", i+1);
588 uart->ick = NULL;
589 }
590
591 sprintf(name, "uart%d_fck", i+1);
592 uart->fck = clk_get(NULL, name);
593 if (IS_ERR(uart->fck)) {
594 printk(KERN_ERR "Could not get uart%d_fck\n", i+1);
595 uart->fck = NULL;
596 }
597
598 if (!uart->ick || !uart->fck)
599 continue;
600
601 uart->num = i;
602 p->private_data = uart;
603 uart->p = p;
604 list_add_tail(&uart->node, &uart_list);
605
606 if (cpu_is_omap44xx())
607 p->irq += 32;
608
609 omap_uart_enable_clocks(uart);
610 omap_uart_reset(uart);
611 omap_uart_idle_init(uart);
612
613 if (WARN_ON(platform_device_register(pdev)))
614 continue;
615 if ((cpu_is_omap34xx() && uart->padconf) ||
616 (uart->wk_en && uart->wk_mask)) {
617 device_init_wakeup(dev, true);
618 DEV_CREATE_FILE(dev, &dev_attr_sleep_timeout);
619 }
620 }
621 }
Linux with added FPC-III support