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Merge tag 'v3.3.7' into 3.3/master
[zen-stable.git] / drivers / tty / serial / omap-serial.c
blob0121486ac4fafbf3bf162ef3744772255e8380e5
1 /*
2 * Driver for OMAP-UART controller.
3 * Based on drivers/serial/8250.c
4 *
5 * Copyright (C) 2010 Texas Instruments.
6 *
7 * Authors:
8 * Govindraj R <govindraj.raja@ti.com>
9 * Thara Gopinath <thara@ti.com>
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or
14 * (at your option) any later version.
15 *
16 * Note: This driver is made separate from 8250 driver as we cannot
17 * over load 8250 driver with omap platform specific configuration for
18 * features like DMA, it makes easier to implement features like DMA and
19 * hardware flow control and software flow control configuration with
20 * this driver as required for the omap-platform.
21 */
22
23 #if defined(CONFIG_SERIAL_OMAP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
24 #define SUPPORT_SYSRQ
25 #endif
26
27 #include <linux/module.h>
28 #include <linux/init.h>
29 #include <linux/console.h>
30 #include <linux/serial_reg.h>
31 #include <linux/delay.h>
32 #include <linux/slab.h>
33 #include <linux/tty.h>
34 #include <linux/tty_flip.h>
35 #include <linux/io.h>
36 #include <linux/dma-mapping.h>
37 #include <linux/clk.h>
38 #include <linux/serial_core.h>
39 #include <linux/irq.h>
40 #include <linux/pm_runtime.h>
41 #include <linux/of.h>
42
43 #include <plat/dma.h>
44 #include <plat/dmtimer.h>
45 #include <plat/omap-serial.h>
46
47 #define DEFAULT_CLK_SPEED 48000000 /* 48Mhz*/
48
49 /* SCR register bitmasks */
50 #define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK (1 << 7)
51
52 /* FCR register bitmasks */
53 #define OMAP_UART_FCR_RX_FIFO_TRIG_SHIFT 6
54 #define OMAP_UART_FCR_RX_FIFO_TRIG_MASK (0x3 << 6)
55
56 static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
57
58 /* Forward declaration of functions */
59 static void uart_tx_dma_callback(int lch, u16 ch_status, void *data);
60 static void serial_omap_rxdma_poll(unsigned long uart_no);
61 static int serial_omap_start_rxdma(struct uart_omap_port *up);
62 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1);
63
64 static struct workqueue_struct *serial_omap_uart_wq;
65
66 static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
67 {
68 offset <<= up->port.regshift;
69 return readw(up->port.membase + offset);
70 }
71
72 static inline void serial_out(struct uart_omap_port *up, int offset, int value)
73 {
74 offset <<= up->port.regshift;
75 writew(value, up->port.membase + offset);
76 }
77
78 static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
79 {
80 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
81 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
82 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
83 serial_out(up, UART_FCR, 0);
84 }
85
86 /*
87 * serial_omap_get_divisor - calculate divisor value
88 * @port: uart port info
89 * @baud: baudrate for which divisor needs to be calculated.
90 *
91 * We have written our own function to get the divisor so as to support
92 * 13x mode. 3Mbps Baudrate as an different divisor.
93 * Reference OMAP TRM Chapter 17:
94 * Table 17-1. UART Mode Baud Rates, Divisor Values, and Error Rates
95 * referring to oversampling - divisor value
96 * baudrate 460,800 to 3,686,400 all have divisor 13
97 * except 3,000,000 which has divisor value 16
98 */
99 static unsigned int
100 serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
101 {
102 unsigned int divisor;
103
104 if (baud > OMAP_MODE13X_SPEED && baud != 3000000)
105 divisor = 13;
106 else
107 divisor = 16;
108 return port->uartclk/(baud * divisor);
109 }
110
111 static void serial_omap_stop_rxdma(struct uart_omap_port *up)
112 {
113 if (up->uart_dma.rx_dma_used) {
114 del_timer(&up->uart_dma.rx_timer);
115 omap_stop_dma(up->uart_dma.rx_dma_channel);
116 omap_free_dma(up->uart_dma.rx_dma_channel);
117 up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE;
118 up->uart_dma.rx_dma_used = false;
119 pm_runtime_mark_last_busy(&up->pdev->dev);
120 pm_runtime_put_autosuspend(&up->pdev->dev);
121 }
122 }
123
124 static void serial_omap_enable_ms(struct uart_port *port)
125 {
126 struct uart_omap_port *up = (struct uart_omap_port *)port;
127
128 dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
129
130 pm_runtime_get_sync(&up->pdev->dev);
131 up->ier |= UART_IER_MSI;
132 serial_out(up, UART_IER, up->ier);
133 pm_runtime_put(&up->pdev->dev);
134 }
135
136 static void serial_omap_stop_tx(struct uart_port *port)
137 {
138 struct uart_omap_port *up = (struct uart_omap_port *)port;
139 struct omap_uart_port_info *pdata = up->pdev->dev.platform_data;
140
141 if (up->use_dma &&
142 up->uart_dma.tx_dma_channel != OMAP_UART_DMA_CH_FREE) {
143 /*
144 * Check if dma is still active. If yes do nothing,
145 * return. Else stop dma
146 */
147 if (omap_get_dma_active_status(up->uart_dma.tx_dma_channel))
148 return;
149 omap_stop_dma(up->uart_dma.tx_dma_channel);
150 omap_free_dma(up->uart_dma.tx_dma_channel);
151 up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE;
152 pm_runtime_mark_last_busy(&up->pdev->dev);
153 pm_runtime_put_autosuspend(&up->pdev->dev);
154 }
155
156 pm_runtime_get_sync(&up->pdev->dev);
157 if (up->ier & UART_IER_THRI) {
158 up->ier &= ~UART_IER_THRI;
159 serial_out(up, UART_IER, up->ier);
160 }
161
162 if (!up->use_dma && pdata && pdata->set_forceidle)
163 pdata->set_forceidle(up->pdev);
164
165 pm_runtime_mark_last_busy(&up->pdev->dev);
166 pm_runtime_put_autosuspend(&up->pdev->dev);
167 }
168
169 static void serial_omap_stop_rx(struct uart_port *port)
170 {
171 struct uart_omap_port *up = (struct uart_omap_port *)port;
172
173 pm_runtime_get_sync(&up->pdev->dev);
174 if (up->use_dma)
175 serial_omap_stop_rxdma(up);
176 up->ier &= ~UART_IER_RLSI;
177 up->port.read_status_mask &= ~UART_LSR_DR;
178 serial_out(up, UART_IER, up->ier);
179 pm_runtime_mark_last_busy(&up->pdev->dev);
180 pm_runtime_put_autosuspend(&up->pdev->dev);
181 }
182
183 static inline void receive_chars(struct uart_omap_port *up,
184 unsigned int *status)
185 {
186 struct tty_struct *tty = up->port.state->port.tty;
187 unsigned int flag, lsr = *status;
188 unsigned char ch = 0;
189 int max_count = 256;
190
191 do {
192 if (likely(lsr & UART_LSR_DR))
193 ch = serial_in(up, UART_RX);
194 flag = TTY_NORMAL;
195 up->port.icount.rx++;
196
197 if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) {
198 /*
199 * For statistics only
200 */
201 if (lsr & UART_LSR_BI) {
202 lsr &= ~(UART_LSR_FE | UART_LSR_PE);
203 up->port.icount.brk++;
204 /*
205 * We do the SysRQ and SAK checking
206 * here because otherwise the break
207 * may get masked by ignore_status_mask
208 * or read_status_mask.
209 */
210 if (uart_handle_break(&up->port))
211 goto ignore_char;
212 } else if (lsr & UART_LSR_PE) {
213 up->port.icount.parity++;
214 } else if (lsr & UART_LSR_FE) {
215 up->port.icount.frame++;
216 }
217
218 if (lsr & UART_LSR_OE)
219 up->port.icount.overrun++;
220
221 /*
222 * Mask off conditions which should be ignored.
223 */
224 lsr &= up->port.read_status_mask;
225
226 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
227 if (up->port.line == up->port.cons->index) {
228 /* Recover the break flag from console xmit */
229 lsr |= up->lsr_break_flag;
230 }
231 #endif
232 if (lsr & UART_LSR_BI)
233 flag = TTY_BREAK;
234 else if (lsr & UART_LSR_PE)
235 flag = TTY_PARITY;
236 else if (lsr & UART_LSR_FE)
237 flag = TTY_FRAME;
238 }
239
240 if (uart_handle_sysrq_char(&up->port, ch))
241 goto ignore_char;
242 uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
243 ignore_char:
244 lsr = serial_in(up, UART_LSR);
245 } while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (max_count-- > 0));
246 spin_unlock(&up->port.lock);
247 tty_flip_buffer_push(tty);
248 spin_lock(&up->port.lock);
249 }
250
251 static void transmit_chars(struct uart_omap_port *up)
252 {
253 struct circ_buf *xmit = &up->port.state->xmit;
254 int count;
255
256 if (up->port.x_char) {
257 serial_out(up, UART_TX, up->port.x_char);
258 up->port.icount.tx++;
259 up->port.x_char = 0;
260 return;
261 }
262 if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
263 serial_omap_stop_tx(&up->port);
264 return;
265 }
266 count = up->port.fifosize / 4;
267 do {
268 serial_out(up, UART_TX, xmit->buf[xmit->tail]);
269 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
270 up->port.icount.tx++;
271 if (uart_circ_empty(xmit))
272 break;
273 } while (--count > 0);
274
275 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
276 uart_write_wakeup(&up->port);
277
278 if (uart_circ_empty(xmit))
279 serial_omap_stop_tx(&up->port);
280 }
281
282 static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
283 {
284 if (!(up->ier & UART_IER_THRI)) {
285 up->ier |= UART_IER_THRI;
286 serial_out(up, UART_IER, up->ier);
287 }
288 }
289
290 static void serial_omap_start_tx(struct uart_port *port)
291 {
292 struct uart_omap_port *up = (struct uart_omap_port *)port;
293 struct omap_uart_port_info *pdata = up->pdev->dev.platform_data;
294 struct circ_buf *xmit;
295 unsigned int start;
296 int ret = 0;
297
298 if (!up->use_dma) {
299 pm_runtime_get_sync(&up->pdev->dev);
300 serial_omap_enable_ier_thri(up);
301 if (pdata && pdata->set_noidle)
302 pdata->set_noidle(up->pdev);
303 pm_runtime_mark_last_busy(&up->pdev->dev);
304 pm_runtime_put_autosuspend(&up->pdev->dev);
305 return;
306 }
307
308 if (up->uart_dma.tx_dma_used)
309 return;
310
311 xmit = &up->port.state->xmit;
312
313 if (up->uart_dma.tx_dma_channel == OMAP_UART_DMA_CH_FREE) {
314 pm_runtime_get_sync(&up->pdev->dev);
315 ret = omap_request_dma(up->uart_dma.uart_dma_tx,
316 "UART Tx DMA",
317 (void *)uart_tx_dma_callback, up,
318 &(up->uart_dma.tx_dma_channel));
319
320 if (ret < 0) {
321 serial_omap_enable_ier_thri(up);
322 return;
323 }
324 }
325 spin_lock(&(up->uart_dma.tx_lock));
326 up->uart_dma.tx_dma_used = true;
327 spin_unlock(&(up->uart_dma.tx_lock));
328
329 start = up->uart_dma.tx_buf_dma_phys +
330 (xmit->tail & (UART_XMIT_SIZE - 1));
331
332 up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit);
333 /*
334 * It is a circular buffer. See if the buffer has wounded back.
335 * If yes it will have to be transferred in two separate dma
336 * transfers
337 */
338 if (start + up->uart_dma.tx_buf_size >=
339 up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE)
340 up->uart_dma.tx_buf_size =
341 (up->uart_dma.tx_buf_dma_phys +
342 UART_XMIT_SIZE) - start;
343
344 omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0,
345 OMAP_DMA_AMODE_CONSTANT,
346 up->uart_dma.uart_base, 0, 0);
347 omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0,
348 OMAP_DMA_AMODE_POST_INC, start, 0, 0);
349 omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel,
350 OMAP_DMA_DATA_TYPE_S8,
351 up->uart_dma.tx_buf_size, 1,
352 OMAP_DMA_SYNC_ELEMENT,
353 up->uart_dma.uart_dma_tx, 0);
354 /* FIXME: Cache maintenance needed here? */
355 omap_start_dma(up->uart_dma.tx_dma_channel);
356 }
357
358 static unsigned int check_modem_status(struct uart_omap_port *up)
359 {
360 unsigned int status;
361
362 status = serial_in(up, UART_MSR);
363 status |= up->msr_saved_flags;
364 up->msr_saved_flags = 0;
365 if ((status & UART_MSR_ANY_DELTA) == 0)
366 return status;
367
368 if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
369 up->port.state != NULL) {
370 if (status & UART_MSR_TERI)
371 up->port.icount.rng++;
372 if (status & UART_MSR_DDSR)
373 up->port.icount.dsr++;
374 if (status & UART_MSR_DDCD)
375 uart_handle_dcd_change
376 (&up->port, status & UART_MSR_DCD);
377 if (status & UART_MSR_DCTS)
378 uart_handle_cts_change
379 (&up->port, status & UART_MSR_CTS);
380 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
381 }
382
383 return status;
384 }
385
386 /**
387 * serial_omap_irq() - This handles the interrupt from one port
388 * @irq: uart port irq number
389 * @dev_id: uart port info
390 */
391 static inline irqreturn_t serial_omap_irq(int irq, void *dev_id)
392 {
393 struct uart_omap_port *up = dev_id;
394 unsigned int iir, lsr;
395 unsigned long flags;
396
397 pm_runtime_get_sync(&up->pdev->dev);
398 iir = serial_in(up, UART_IIR);
399 if (iir & UART_IIR_NO_INT) {
400 pm_runtime_mark_last_busy(&up->pdev->dev);
401 pm_runtime_put_autosuspend(&up->pdev->dev);
402 return IRQ_NONE;
403 }
404
405 spin_lock_irqsave(&up->port.lock, flags);
406 lsr = serial_in(up, UART_LSR);
407 if (iir & UART_IIR_RLSI) {
408 if (!up->use_dma) {
409 if (lsr & UART_LSR_DR)
410 receive_chars(up, &lsr);
411 } else {
412 up->ier &= ~(UART_IER_RDI | UART_IER_RLSI);
413 serial_out(up, UART_IER, up->ier);
414 if ((serial_omap_start_rxdma(up) != 0) &&
415 (lsr & UART_LSR_DR))
416 receive_chars(up, &lsr);
417 }
418 }
419
420 check_modem_status(up);
421 if ((lsr & UART_LSR_THRE) && (iir & UART_IIR_THRI))
422 transmit_chars(up);
423
424 spin_unlock_irqrestore(&up->port.lock, flags);
425 pm_runtime_mark_last_busy(&up->pdev->dev);
426 pm_runtime_put_autosuspend(&up->pdev->dev);
427
428 up->port_activity = jiffies;
429 return IRQ_HANDLED;
430 }
431
432 static unsigned int serial_omap_tx_empty(struct uart_port *port)
433 {
434 struct uart_omap_port *up = (struct uart_omap_port *)port;
435 unsigned long flags = 0;
436 unsigned int ret = 0;
437
438 pm_runtime_get_sync(&up->pdev->dev);
439 dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line);
440 spin_lock_irqsave(&up->port.lock, flags);
441 ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
442 spin_unlock_irqrestore(&up->port.lock, flags);
443 pm_runtime_put(&up->pdev->dev);
444 return ret;
445 }
446
447 static unsigned int serial_omap_get_mctrl(struct uart_port *port)
448 {
449 struct uart_omap_port *up = (struct uart_omap_port *)port;
450 unsigned int status;
451 unsigned int ret = 0;
452
453 pm_runtime_get_sync(&up->pdev->dev);
454 status = check_modem_status(up);
455 pm_runtime_put(&up->pdev->dev);
456
457 dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line);
458
459 if (status & UART_MSR_DCD)
460 ret |= TIOCM_CAR;
461 if (status & UART_MSR_RI)
462 ret |= TIOCM_RNG;
463 if (status & UART_MSR_DSR)
464 ret |= TIOCM_DSR;
465 if (status & UART_MSR_CTS)
466 ret |= TIOCM_CTS;
467 return ret;
468 }
469
470 static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
471 {
472 struct uart_omap_port *up = (struct uart_omap_port *)port;
473 unsigned char mcr = 0;
474
475 dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
476 if (mctrl & TIOCM_RTS)
477 mcr |= UART_MCR_RTS;
478 if (mctrl & TIOCM_DTR)
479 mcr |= UART_MCR_DTR;
480 if (mctrl & TIOCM_OUT1)
481 mcr |= UART_MCR_OUT1;
482 if (mctrl & TIOCM_OUT2)
483 mcr |= UART_MCR_OUT2;
484 if (mctrl & TIOCM_LOOP)
485 mcr |= UART_MCR_LOOP;
486
487 pm_runtime_get_sync(&up->pdev->dev);
488 up->mcr = serial_in(up, UART_MCR);
489 up->mcr |= mcr;
490 serial_out(up, UART_MCR, up->mcr);
491 pm_runtime_put(&up->pdev->dev);
492 }
493
494 static void serial_omap_break_ctl(struct uart_port *port, int break_state)
495 {
496 struct uart_omap_port *up = (struct uart_omap_port *)port;
497 unsigned long flags = 0;
498
499 dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
500 pm_runtime_get_sync(&up->pdev->dev);
501 spin_lock_irqsave(&up->port.lock, flags);
502 if (break_state == -1)
503 up->lcr |= UART_LCR_SBC;
504 else
505 up->lcr &= ~UART_LCR_SBC;
506 serial_out(up, UART_LCR, up->lcr);
507 spin_unlock_irqrestore(&up->port.lock, flags);
508 pm_runtime_put(&up->pdev->dev);
509 }
510
511 static int serial_omap_startup(struct uart_port *port)
512 {
513 struct uart_omap_port *up = (struct uart_omap_port *)port;
514 unsigned long flags = 0;
515 int retval;
516
517 /*
518 * Allocate the IRQ
519 */
520 retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
521 up->name, up);
522 if (retval)
523 return retval;
524
525 dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
526
527 pm_runtime_get_sync(&up->pdev->dev);
528 /*
529 * Clear the FIFO buffers and disable them.
530 * (they will be reenabled in set_termios())
531 */
532 serial_omap_clear_fifos(up);
533 /* For Hardware flow control */
534 serial_out(up, UART_MCR, UART_MCR_RTS);
535
536 /*
537 * Clear the interrupt registers.
538 */
539 (void) serial_in(up, UART_LSR);
540 if (serial_in(up, UART_LSR) & UART_LSR_DR)
541 (void) serial_in(up, UART_RX);
542 (void) serial_in(up, UART_IIR);
543 (void) serial_in(up, UART_MSR);
544
545 /*
546 * Now, initialize the UART
547 */
548 serial_out(up, UART_LCR, UART_LCR_WLEN8);
549 spin_lock_irqsave(&up->port.lock, flags);
550 /*
551 * Most PC uarts need OUT2 raised to enable interrupts.
552 */
553 up->port.mctrl |= TIOCM_OUT2;
554 serial_omap_set_mctrl(&up->port, up->port.mctrl);
555 spin_unlock_irqrestore(&up->port.lock, flags);
556
557 up->msr_saved_flags = 0;
558 if (up->use_dma) {
559 free_page((unsigned long)up->port.state->xmit.buf);
560 up->port.state->xmit.buf = dma_alloc_coherent(NULL,
561 UART_XMIT_SIZE,
562 (dma_addr_t *)&(up->uart_dma.tx_buf_dma_phys),
563 0);
564 init_timer(&(up->uart_dma.rx_timer));
565 up->uart_dma.rx_timer.function = serial_omap_rxdma_poll;
566 up->uart_dma.rx_timer.data = up->port.line;
567 /* Currently the buffer size is 4KB. Can increase it */
568 up->uart_dma.rx_buf = dma_alloc_coherent(NULL,
569 up->uart_dma.rx_buf_size,
570 (dma_addr_t *)&(up->uart_dma.rx_buf_dma_phys), 0);
571 }
572 /*
573 * Finally, enable interrupts. Note: Modem status interrupts
574 * are set via set_termios(), which will be occurring imminently
575 * anyway, so we don't enable them here.
576 */
577 up->ier = UART_IER_RLSI | UART_IER_RDI;
578 serial_out(up, UART_IER, up->ier);
579
580 /* Enable module level wake up */
581 serial_out(up, UART_OMAP_WER, OMAP_UART_WER_MOD_WKUP);
582
583 pm_runtime_mark_last_busy(&up->pdev->dev);
584 pm_runtime_put_autosuspend(&up->pdev->dev);
585 up->port_activity = jiffies;
586 return 0;
587 }
588
589 static void serial_omap_shutdown(struct uart_port *port)
590 {
591 struct uart_omap_port *up = (struct uart_omap_port *)port;
592 unsigned long flags = 0;
593
594 dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
595
596 pm_runtime_get_sync(&up->pdev->dev);
597 /*
598 * Disable interrupts from this port
599 */
600 up->ier = 0;
601 serial_out(up, UART_IER, 0);
602
603 spin_lock_irqsave(&up->port.lock, flags);
604 up->port.mctrl &= ~TIOCM_OUT2;
605 serial_omap_set_mctrl(&up->port, up->port.mctrl);
606 spin_unlock_irqrestore(&up->port.lock, flags);
607
608 /*
609 * Disable break condition and FIFOs
610 */
611 serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
612 serial_omap_clear_fifos(up);
613
614 /*
615 * Read data port to reset things, and then free the irq
616 */
617 if (serial_in(up, UART_LSR) & UART_LSR_DR)
618 (void) serial_in(up, UART_RX);
619 if (up->use_dma) {
620 dma_free_coherent(up->port.dev,
621 UART_XMIT_SIZE, up->port.state->xmit.buf,
622 up->uart_dma.tx_buf_dma_phys);
623 up->port.state->xmit.buf = NULL;
624 serial_omap_stop_rx(port);
625 dma_free_coherent(up->port.dev,
626 up->uart_dma.rx_buf_size, up->uart_dma.rx_buf,
627 up->uart_dma.rx_buf_dma_phys);
628 up->uart_dma.rx_buf = NULL;
629 }
630
631 pm_runtime_put(&up->pdev->dev);
632 free_irq(up->port.irq, up);
633 }
634
635 static inline void
636 serial_omap_configure_xonxoff
637 (struct uart_omap_port *up, struct ktermios *termios)
638 {
639 up->lcr = serial_in(up, UART_LCR);
640 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
641 up->efr = serial_in(up, UART_EFR);
642 serial_out(up, UART_EFR, up->efr & ~UART_EFR_ECB);
643
644 serial_out(up, UART_XON1, termios->c_cc[VSTART]);
645 serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
646
647 /* clear SW control mode bits */
648 up->efr &= OMAP_UART_SW_CLR;
649
650 /*
651 * IXON Flag:
652 * Enable XON/XOFF flow control on output.
653 * Transmit XON1, XOFF1
654 */
655 if (termios->c_iflag & IXON)
656 up->efr |= OMAP_UART_SW_TX;
657
658 /*
659 * IXOFF Flag:
660 * Enable XON/XOFF flow control on input.
661 * Receiver compares XON1, XOFF1.
662 */
663 if (termios->c_iflag & IXOFF)
664 up->efr |= OMAP_UART_SW_RX;
665
666 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
667 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
668
669 up->mcr = serial_in(up, UART_MCR);
670
671 /*
672 * IXANY Flag:
673 * Enable any character to restart output.
674 * Operation resumes after receiving any
675 * character after recognition of the XOFF character
676 */
677 if (termios->c_iflag & IXANY)
678 up->mcr |= UART_MCR_XONANY;
679
680 serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
681 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
682 serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
683 /* Enable special char function UARTi.EFR_REG[5] and
684 * load the new software flow control mode IXON or IXOFF
685 * and restore the UARTi.EFR_REG[4] ENHANCED_EN value.
686 */
687 serial_out(up, UART_EFR, up->efr | UART_EFR_SCD);
688 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
689
690 serial_out(up, UART_MCR, up->mcr & ~UART_MCR_TCRTLR);
691 serial_out(up, UART_LCR, up->lcr);
692 }
693
694 static void serial_omap_uart_qos_work(struct work_struct *work)
695 {
696 struct uart_omap_port *up = container_of(work, struct uart_omap_port,
697 qos_work);
698
699 pm_qos_update_request(&up->pm_qos_request, up->latency);
700 }
701
702 static void
703 serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
704 struct ktermios *old)
705 {
706 struct uart_omap_port *up = (struct uart_omap_port *)port;
707 unsigned char cval = 0;
708 unsigned char efr = 0;
709 unsigned long flags = 0;
710 unsigned int baud, quot;
711
712 switch (termios->c_cflag & CSIZE) {
713 case CS5:
714 cval = UART_LCR_WLEN5;
715 break;
716 case CS6:
717 cval = UART_LCR_WLEN6;
718 break;
719 case CS7:
720 cval = UART_LCR_WLEN7;
721 break;
722 default:
723 case CS8:
724 cval = UART_LCR_WLEN8;
725 break;
726 }
727
728 if (termios->c_cflag & CSTOPB)
729 cval |= UART_LCR_STOP;
730 if (termios->c_cflag & PARENB)
731 cval |= UART_LCR_PARITY;
732 if (!(termios->c_cflag & PARODD))
733 cval |= UART_LCR_EPAR;
734
735 /*
736 * Ask the core to calculate the divisor for us.
737 */
738
739 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
740 quot = serial_omap_get_divisor(port, baud);
741
742 /* calculate wakeup latency constraint */
743 up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
744 up->latency = up->calc_latency;
745 schedule_work(&up->qos_work);
746
747 up->dll = quot & 0xff;
748 up->dlh = quot >> 8;
749 up->mdr1 = UART_OMAP_MDR1_DISABLE;
750
751 up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
752 UART_FCR_ENABLE_FIFO;
753 if (up->use_dma)
754 up->fcr |= UART_FCR_DMA_SELECT;
755
756 /*
757 * Ok, we're now changing the port state. Do it with
758 * interrupts disabled.
759 */
760 pm_runtime_get_sync(&up->pdev->dev);
761 spin_lock_irqsave(&up->port.lock, flags);
762
763 /*
764 * Update the per-port timeout.
765 */
766 uart_update_timeout(port, termios->c_cflag, baud);
767
768 up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
769 if (termios->c_iflag & INPCK)
770 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
771 if (termios->c_iflag & (BRKINT | PARMRK))
772 up->port.read_status_mask |= UART_LSR_BI;
773
774 /*
775 * Characters to ignore
776 */
777 up->port.ignore_status_mask = 0;
778 if (termios->c_iflag & IGNPAR)
779 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
780 if (termios->c_iflag & IGNBRK) {
781 up->port.ignore_status_mask |= UART_LSR_BI;
782 /*
783 * If we're ignoring parity and break indicators,
784 * ignore overruns too (for real raw support).
785 */
786 if (termios->c_iflag & IGNPAR)
787 up->port.ignore_status_mask |= UART_LSR_OE;
788 }
789
790 /*
791 * ignore all characters if CREAD is not set
792 */
793 if ((termios->c_cflag & CREAD) == 0)
794 up->port.ignore_status_mask |= UART_LSR_DR;
795
796 /*
797 * Modem status interrupts
798 */
799 up->ier &= ~UART_IER_MSI;
800 if (UART_ENABLE_MS(&up->port, termios->c_cflag))
801 up->ier |= UART_IER_MSI;
802 serial_out(up, UART_IER, up->ier);
803 serial_out(up, UART_LCR, cval); /* reset DLAB */
804 up->lcr = cval;
805 up->scr = OMAP_UART_SCR_TX_EMPTY;
806
807 /* FIFOs and DMA Settings */
808
809 /* FCR can be changed only when the
810 * baud clock is not running
811 * DLL_REG and DLH_REG set to 0.
812 */
813 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
814 serial_out(up, UART_DLL, 0);
815 serial_out(up, UART_DLM, 0);
816 serial_out(up, UART_LCR, 0);
817
818 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
819
820 up->efr = serial_in(up, UART_EFR);
821 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
822
823 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
824 up->mcr = serial_in(up, UART_MCR);
825 serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
826 /* FIFO ENABLE, DMA MODE */
827
828 up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
829
830 if (up->use_dma) {
831 serial_out(up, UART_TI752_TLR, 0);
832 up->scr |= UART_FCR_TRIGGER_4;
833 } else {
834 /* Set receive FIFO threshold to 1 byte */
835 up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
836 up->fcr |= (0x1 << OMAP_UART_FCR_RX_FIFO_TRIG_SHIFT);
837 }
838
839 serial_out(up, UART_FCR, up->fcr);
840 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
841
842 serial_out(up, UART_OMAP_SCR, up->scr);
843
844 serial_out(up, UART_EFR, up->efr);
845 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
846 serial_out(up, UART_MCR, up->mcr);
847
848 /* Protocol, Baud Rate, and Interrupt Settings */
849
850 if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
851 serial_omap_mdr1_errataset(up, up->mdr1);
852 else
853 serial_out(up, UART_OMAP_MDR1, up->mdr1);
854
855 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
856
857 up->efr = serial_in(up, UART_EFR);
858 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
859
860 serial_out(up, UART_LCR, 0);
861 serial_out(up, UART_IER, 0);
862 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
863
864 serial_out(up, UART_DLL, up->dll); /* LS of divisor */
865 serial_out(up, UART_DLM, up->dlh); /* MS of divisor */
866
867 serial_out(up, UART_LCR, 0);
868 serial_out(up, UART_IER, up->ier);
869 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
870
871 serial_out(up, UART_EFR, up->efr);
872 serial_out(up, UART_LCR, cval);
873
874 if (baud > 230400 && baud != 3000000)
875 up->mdr1 = UART_OMAP_MDR1_13X_MODE;
876 else
877 up->mdr1 = UART_OMAP_MDR1_16X_MODE;
878
879 if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
880 serial_omap_mdr1_errataset(up, up->mdr1);
881 else
882 serial_out(up, UART_OMAP_MDR1, up->mdr1);
883
884 /* Hardware Flow Control Configuration */
885
886 if (termios->c_cflag & CRTSCTS) {
887 efr |= (UART_EFR_CTS | UART_EFR_RTS);
888 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
889
890 up->mcr = serial_in(up, UART_MCR);
891 serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
892
893 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
894 up->efr = serial_in(up, UART_EFR);
895 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
896
897 serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
898 serial_out(up, UART_EFR, efr); /* Enable AUTORTS and AUTOCTS */
899 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
900 serial_out(up, UART_MCR, up->mcr | UART_MCR_RTS);
901 serial_out(up, UART_LCR, cval);
902 }
903
904 serial_omap_set_mctrl(&up->port, up->port.mctrl);
905 /* Software Flow Control Configuration */
906 serial_omap_configure_xonxoff(up, termios);
907
908 spin_unlock_irqrestore(&up->port.lock, flags);
909 pm_runtime_put(&up->pdev->dev);
910 dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
911 }
912
913 static void
914 serial_omap_pm(struct uart_port *port, unsigned int state,
915 unsigned int oldstate)
916 {
917 struct uart_omap_port *up = (struct uart_omap_port *)port;
918 unsigned char efr;
919
920 dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line);
921
922 pm_runtime_get_sync(&up->pdev->dev);
923 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
924 efr = serial_in(up, UART_EFR);
925 serial_out(up, UART_EFR, efr | UART_EFR_ECB);
926 serial_out(up, UART_LCR, 0);
927
928 serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
929 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
930 serial_out(up, UART_EFR, efr);
931 serial_out(up, UART_LCR, 0);
932
933 if (!device_may_wakeup(&up->pdev->dev)) {
934 if (!state)
935 pm_runtime_forbid(&up->pdev->dev);
936 else
937 pm_runtime_allow(&up->pdev->dev);
938 }
939
940 pm_runtime_put(&up->pdev->dev);
941 }
942
943 static void serial_omap_release_port(struct uart_port *port)
944 {
945 dev_dbg(port->dev, "serial_omap_release_port+\n");
946 }
947
948 static int serial_omap_request_port(struct uart_port *port)
949 {
950 dev_dbg(port->dev, "serial_omap_request_port+\n");
951 return 0;
952 }
953
954 static void serial_omap_config_port(struct uart_port *port, int flags)
955 {
956 struct uart_omap_port *up = (struct uart_omap_port *)port;
957
958 dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
959 up->port.line);
960 up->port.type = PORT_OMAP;
961 }
962
963 static int
964 serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
965 {
966 /* we don't want the core code to modify any port params */
967 dev_dbg(port->dev, "serial_omap_verify_port+\n");
968 return -EINVAL;
969 }
970
971 static const char *
972 serial_omap_type(struct uart_port *port)
973 {
974 struct uart_omap_port *up = (struct uart_omap_port *)port;
975
976 dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
977 return up->name;
978 }
979
980 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
981
982 static inline void wait_for_xmitr(struct uart_omap_port *up)
983 {
984 unsigned int status, tmout = 10000;
985
986 /* Wait up to 10ms for the character(s) to be sent. */
987 do {
988 status = serial_in(up, UART_LSR);
989
990 if (status & UART_LSR_BI)
991 up->lsr_break_flag = UART_LSR_BI;
992
993 if (--tmout == 0)
994 break;
995 udelay(1);
996 } while ((status & BOTH_EMPTY) != BOTH_EMPTY);
997
998 /* Wait up to 1s for flow control if necessary */
999 if (up->port.flags & UPF_CONS_FLOW) {
1000 tmout = 1000000;
1001 for (tmout = 1000000; tmout; tmout--) {
1002 unsigned int msr = serial_in(up, UART_MSR);
1003
1004 up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
1005 if (msr & UART_MSR_CTS)
1006 break;
1007
1008 udelay(1);
1009 }
1010 }
1011 }
1012
1013 #ifdef CONFIG_CONSOLE_POLL
1014
1015 static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
1016 {
1017 struct uart_omap_port *up = (struct uart_omap_port *)port;
1018
1019 pm_runtime_get_sync(&up->pdev->dev);
1020 wait_for_xmitr(up);
1021 serial_out(up, UART_TX, ch);
1022 pm_runtime_put(&up->pdev->dev);
1023 }
1024
1025 static int serial_omap_poll_get_char(struct uart_port *port)
1026 {
1027 struct uart_omap_port *up = (struct uart_omap_port *)port;
1028 unsigned int status;
1029
1030 pm_runtime_get_sync(&up->pdev->dev);
1031 status = serial_in(up, UART_LSR);
1032 if (!(status & UART_LSR_DR))
1033 return NO_POLL_CHAR;
1034
1035 status = serial_in(up, UART_RX);
1036 pm_runtime_put(&up->pdev->dev);
1037 return status;
1038 }
1039
1040 #endif /* CONFIG_CONSOLE_POLL */
1041
1042 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
1043
1044 static struct uart_omap_port *serial_omap_console_ports[4];
1045
1046 static struct uart_driver serial_omap_reg;
1047
1048 static void serial_omap_console_putchar(struct uart_port *port, int ch)
1049 {
1050 struct uart_omap_port *up = (struct uart_omap_port *)port;
1051
1052 wait_for_xmitr(up);
1053 serial_out(up, UART_TX, ch);
1054 }
1055
1056 static void
1057 serial_omap_console_write(struct console *co, const char *s,
1058 unsigned int count)
1059 {
1060 struct uart_omap_port *up = serial_omap_console_ports[co->index];
1061 unsigned long flags;
1062 unsigned int ier;
1063 int locked = 1;
1064
1065 pm_runtime_get_sync(&up->pdev->dev);
1066
1067 local_irq_save(flags);
1068 if (up->port.sysrq)
1069 locked = 0;
1070 else if (oops_in_progress)
1071 locked = spin_trylock(&up->port.lock);
1072 else
1073 spin_lock(&up->port.lock);
1074
1075 /*
1076 * First save the IER then disable the interrupts
1077 */
1078 ier = serial_in(up, UART_IER);
1079 serial_out(up, UART_IER, 0);
1080
1081 uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1082
1083 /*
1084 * Finally, wait for transmitter to become empty
1085 * and restore the IER
1086 */
1087 wait_for_xmitr(up);
1088 serial_out(up, UART_IER, ier);
1089 /*
1090 * The receive handling will happen properly because the
1091 * receive ready bit will still be set; it is not cleared
1092 * on read. However, modem control will not, we must
1093 * call it if we have saved something in the saved flags
1094 * while processing with interrupts off.
1095 */
1096 if (up->msr_saved_flags)
1097 check_modem_status(up);
1098
1099 pm_runtime_mark_last_busy(&up->pdev->dev);
1100 pm_runtime_put_autosuspend(&up->pdev->dev);
1101 if (locked)
1102 spin_unlock(&up->port.lock);
1103 local_irq_restore(flags);
1104 }
1105
1106 static int __init
1107 serial_omap_console_setup(struct console *co, char *options)
1108 {
1109 struct uart_omap_port *up;
1110 int baud = 115200;
1111 int bits = 8;
1112 int parity = 'n';
1113 int flow = 'n';
1114
1115 if (serial_omap_console_ports[co->index] == NULL)
1116 return -ENODEV;
1117 up = serial_omap_console_ports[co->index];
1118
1119 if (options)
1120 uart_parse_options(options, &baud, &parity, &bits, &flow);
1121
1122 return uart_set_options(&up->port, co, baud, parity, bits, flow);
1123 }
1124
1125 static struct console serial_omap_console = {
1126 .name = OMAP_SERIAL_NAME,
1127 .write = serial_omap_console_write,
1128 .device = uart_console_device,
1129 .setup = serial_omap_console_setup,
1130 .flags = CON_PRINTBUFFER,
1131 .index = -1,
1132 .data = &serial_omap_reg,
1133 };
1134
1135 static void serial_omap_add_console_port(struct uart_omap_port *up)
1136 {
1137 serial_omap_console_ports[up->port.line] = up;
1138 }
1139
1140 #define OMAP_CONSOLE (&serial_omap_console)
1141
1142 #else
1143
1144 #define OMAP_CONSOLE NULL
1145
1146 static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1147 {}
1148
1149 #endif
1150
1151 static struct uart_ops serial_omap_pops = {
1152 .tx_empty = serial_omap_tx_empty,
1153 .set_mctrl = serial_omap_set_mctrl,
1154 .get_mctrl = serial_omap_get_mctrl,
1155 .stop_tx = serial_omap_stop_tx,
1156 .start_tx = serial_omap_start_tx,
1157 .stop_rx = serial_omap_stop_rx,
1158 .enable_ms = serial_omap_enable_ms,
1159 .break_ctl = serial_omap_break_ctl,
1160 .startup = serial_omap_startup,
1161 .shutdown = serial_omap_shutdown,
1162 .set_termios = serial_omap_set_termios,
1163 .pm = serial_omap_pm,
1164 .type = serial_omap_type,
1165 .release_port = serial_omap_release_port,
1166 .request_port = serial_omap_request_port,
1167 .config_port = serial_omap_config_port,
1168 .verify_port = serial_omap_verify_port,
1169 #ifdef CONFIG_CONSOLE_POLL
1170 .poll_put_char = serial_omap_poll_put_char,
1171 .poll_get_char = serial_omap_poll_get_char,
1172 #endif
1173 };
1174
1175 static struct uart_driver serial_omap_reg = {
1176 .owner = THIS_MODULE,
1177 .driver_name = "OMAP-SERIAL",
1178 .dev_name = OMAP_SERIAL_NAME,
1179 .nr = OMAP_MAX_HSUART_PORTS,
1180 .cons = OMAP_CONSOLE,
1181 };
1182
1183 #ifdef CONFIG_PM_SLEEP
1184 static int serial_omap_suspend(struct device *dev)
1185 {
1186 struct uart_omap_port *up = dev_get_drvdata(dev);
1187
1188 if (up) {
1189 uart_suspend_port(&serial_omap_reg, &up->port);
1190 flush_work_sync(&up->qos_work);
1191 }
1192
1193 return 0;
1194 }
1195
1196 static int serial_omap_resume(struct device *dev)
1197 {
1198 struct uart_omap_port *up = dev_get_drvdata(dev);
1199
1200 if (up)
1201 uart_resume_port(&serial_omap_reg, &up->port);
1202 return 0;
1203 }
1204 #endif
1205
1206 static void serial_omap_rxdma_poll(unsigned long uart_no)
1207 {
1208 struct uart_omap_port *up = ui[uart_no];
1209 unsigned int curr_dma_pos, curr_transmitted_size;
1210 int ret = 0;
1211
1212 curr_dma_pos = omap_get_dma_dst_pos(up->uart_dma.rx_dma_channel);
1213 if ((curr_dma_pos == up->uart_dma.prev_rx_dma_pos) ||
1214 (curr_dma_pos == 0)) {
1215 if (jiffies_to_msecs(jiffies - up->port_activity) <
1216 up->uart_dma.rx_timeout) {
1217 mod_timer(&up->uart_dma.rx_timer, jiffies +
1218 usecs_to_jiffies(up->uart_dma.rx_poll_rate));
1219 } else {
1220 serial_omap_stop_rxdma(up);
1221 up->ier |= (UART_IER_RDI | UART_IER_RLSI);
1222 serial_out(up, UART_IER, up->ier);
1223 }
1224 return;
1225 }
1226
1227 curr_transmitted_size = curr_dma_pos -
1228 up->uart_dma.prev_rx_dma_pos;
1229 up->port.icount.rx += curr_transmitted_size;
1230 tty_insert_flip_string(up->port.state->port.tty,
1231 up->uart_dma.rx_buf +
1232 (up->uart_dma.prev_rx_dma_pos -
1233 up->uart_dma.rx_buf_dma_phys),
1234 curr_transmitted_size);
1235 tty_flip_buffer_push(up->port.state->port.tty);
1236 up->uart_dma.prev_rx_dma_pos = curr_dma_pos;
1237 if (up->uart_dma.rx_buf_size +
1238 up->uart_dma.rx_buf_dma_phys == curr_dma_pos) {
1239 ret = serial_omap_start_rxdma(up);
1240 if (ret < 0) {
1241 serial_omap_stop_rxdma(up);
1242 up->ier |= (UART_IER_RDI | UART_IER_RLSI);
1243 serial_out(up, UART_IER, up->ier);
1244 }
1245 } else {
1246 mod_timer(&up->uart_dma.rx_timer, jiffies +
1247 usecs_to_jiffies(up->uart_dma.rx_poll_rate));
1248 }
1249 up->port_activity = jiffies;
1250 }
1251
1252 static void uart_rx_dma_callback(int lch, u16 ch_status, void *data)
1253 {
1254 return;
1255 }
1256
1257 static int serial_omap_start_rxdma(struct uart_omap_port *up)
1258 {
1259 int ret = 0;
1260
1261 if (up->uart_dma.rx_dma_channel == -1) {
1262 pm_runtime_get_sync(&up->pdev->dev);
1263 ret = omap_request_dma(up->uart_dma.uart_dma_rx,
1264 "UART Rx DMA",
1265 (void *)uart_rx_dma_callback, up,
1266 &(up->uart_dma.rx_dma_channel));
1267 if (ret < 0)
1268 return ret;
1269
1270 omap_set_dma_src_params(up->uart_dma.rx_dma_channel, 0,
1271 OMAP_DMA_AMODE_CONSTANT,
1272 up->uart_dma.uart_base, 0, 0);
1273 omap_set_dma_dest_params(up->uart_dma.rx_dma_channel, 0,
1274 OMAP_DMA_AMODE_POST_INC,
1275 up->uart_dma.rx_buf_dma_phys, 0, 0);
1276 omap_set_dma_transfer_params(up->uart_dma.rx_dma_channel,
1277 OMAP_DMA_DATA_TYPE_S8,
1278 up->uart_dma.rx_buf_size, 1,
1279 OMAP_DMA_SYNC_ELEMENT,
1280 up->uart_dma.uart_dma_rx, 0);
1281 }
1282 up->uart_dma.prev_rx_dma_pos = up->uart_dma.rx_buf_dma_phys;
1283 /* FIXME: Cache maintenance needed here? */
1284 omap_start_dma(up->uart_dma.rx_dma_channel);
1285 mod_timer(&up->uart_dma.rx_timer, jiffies +
1286 usecs_to_jiffies(up->uart_dma.rx_poll_rate));
1287 up->uart_dma.rx_dma_used = true;
1288 return ret;
1289 }
1290
1291 static void serial_omap_continue_tx(struct uart_omap_port *up)
1292 {
1293 struct circ_buf *xmit = &up->port.state->xmit;
1294 unsigned int start = up->uart_dma.tx_buf_dma_phys
1295 + (xmit->tail & (UART_XMIT_SIZE - 1));
1296
1297 if (uart_circ_empty(xmit))
1298 return;
1299
1300 up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit);
1301 /*
1302 * It is a circular buffer. See if the buffer has wounded back.
1303 * If yes it will have to be transferred in two separate dma
1304 * transfers
1305 */
1306 if (start + up->uart_dma.tx_buf_size >=
1307 up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE)
1308 up->uart_dma.tx_buf_size =
1309 (up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE) - start;
1310 omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0,
1311 OMAP_DMA_AMODE_CONSTANT,
1312 up->uart_dma.uart_base, 0, 0);
1313 omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0,
1314 OMAP_DMA_AMODE_POST_INC, start, 0, 0);
1315 omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel,
1316 OMAP_DMA_DATA_TYPE_S8,
1317 up->uart_dma.tx_buf_size, 1,
1318 OMAP_DMA_SYNC_ELEMENT,
1319 up->uart_dma.uart_dma_tx, 0);
1320 /* FIXME: Cache maintenance needed here? */
1321 omap_start_dma(up->uart_dma.tx_dma_channel);
1322 }
1323
1324 static void uart_tx_dma_callback(int lch, u16 ch_status, void *data)
1325 {
1326 struct uart_omap_port *up = (struct uart_omap_port *)data;
1327 struct circ_buf *xmit = &up->port.state->xmit;
1328
1329 xmit->tail = (xmit->tail + up->uart_dma.tx_buf_size) & \
1330 (UART_XMIT_SIZE - 1);
1331 up->port.icount.tx += up->uart_dma.tx_buf_size;
1332
1333 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1334 uart_write_wakeup(&up->port);
1335
1336 if (uart_circ_empty(xmit)) {
1337 spin_lock(&(up->uart_dma.tx_lock));
1338 serial_omap_stop_tx(&up->port);
1339 up->uart_dma.tx_dma_used = false;
1340 spin_unlock(&(up->uart_dma.tx_lock));
1341 } else {
1342 omap_stop_dma(up->uart_dma.tx_dma_channel);
1343 serial_omap_continue_tx(up);
1344 }
1345 up->port_activity = jiffies;
1346 return;
1347 }
1348
1349 static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
1350 {
1351 struct omap_uart_port_info *omap_up_info;
1352
1353 omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
1354 if (!omap_up_info)
1355 return NULL; /* out of memory */
1356
1357 of_property_read_u32(dev->of_node, "clock-frequency",
1358 &omap_up_info->uartclk);
1359 return omap_up_info;
1360 }
1361
1362 static int serial_omap_probe(struct platform_device *pdev)
1363 {
1364 struct uart_omap_port *up;
1365 struct resource *mem, *irq, *dma_tx, *dma_rx;
1366 struct omap_uart_port_info *omap_up_info = pdev->dev.platform_data;
1367 int ret = -ENOSPC;
1368
1369 if (pdev->dev.of_node)
1370 omap_up_info = of_get_uart_port_info(&pdev->dev);
1371
1372 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1373 if (!mem) {
1374 dev_err(&pdev->dev, "no mem resource?\n");
1375 return -ENODEV;
1376 }
1377
1378 irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1379 if (!irq) {
1380 dev_err(&pdev->dev, "no irq resource?\n");
1381 return -ENODEV;
1382 }
1383
1384 if (!request_mem_region(mem->start, resource_size(mem),
1385 pdev->dev.driver->name)) {
1386 dev_err(&pdev->dev, "memory region already claimed\n");
1387 return -EBUSY;
1388 }
1389
1390 dma_rx = platform_get_resource_byname(pdev, IORESOURCE_DMA, "rx");
1391 if (!dma_rx) {
1392 ret = -EINVAL;
1393 goto err;
1394 }
1395
1396 dma_tx = platform_get_resource_byname(pdev, IORESOURCE_DMA, "tx");
1397 if (!dma_tx) {
1398 ret = -EINVAL;
1399 goto err;
1400 }
1401
1402 up = kzalloc(sizeof(*up), GFP_KERNEL);
1403 if (up == NULL) {
1404 ret = -ENOMEM;
1405 goto do_release_region;
1406 }
1407 up->pdev = pdev;
1408 up->port.dev = &pdev->dev;
1409 up->port.type = PORT_OMAP;
1410 up->port.iotype = UPIO_MEM;
1411 up->port.irq = irq->start;
1412
1413 up->port.regshift = 2;
1414 up->port.fifosize = 64;
1415 up->port.ops = &serial_omap_pops;
1416
1417 if (pdev->dev.of_node)
1418 up->port.line = of_alias_get_id(pdev->dev.of_node, "serial");
1419 else
1420 up->port.line = pdev->id;
1421
1422 if (up->port.line < 0) {
1423 dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
1424 up->port.line);
1425 ret = -ENODEV;
1426 goto err;
1427 }
1428
1429 sprintf(up->name, "OMAP UART%d", up->port.line);
1430 up->port.mapbase = mem->start;
1431 up->port.membase = ioremap(mem->start, resource_size(mem));
1432 if (!up->port.membase) {
1433 dev_err(&pdev->dev, "can't ioremap UART\n");
1434 ret = -ENOMEM;
1435 goto err;
1436 }
1437
1438 up->port.flags = omap_up_info->flags;
1439 up->port.uartclk = omap_up_info->uartclk;
1440 if (!up->port.uartclk) {
1441 up->port.uartclk = DEFAULT_CLK_SPEED;
1442 dev_warn(&pdev->dev, "No clock speed specified: using default:"
1443 "%d\n", DEFAULT_CLK_SPEED);
1444 }
1445 up->uart_dma.uart_base = mem->start;
1446 up->errata = omap_up_info->errata;
1447
1448 if (omap_up_info->dma_enabled) {
1449 up->uart_dma.uart_dma_tx = dma_tx->start;
1450 up->uart_dma.uart_dma_rx = dma_rx->start;
1451 up->use_dma = 1;
1452 up->uart_dma.rx_buf_size = omap_up_info->dma_rx_buf_size;
1453 up->uart_dma.rx_timeout = omap_up_info->dma_rx_timeout;
1454 up->uart_dma.rx_poll_rate = omap_up_info->dma_rx_poll_rate;
1455 spin_lock_init(&(up->uart_dma.tx_lock));
1456 spin_lock_init(&(up->uart_dma.rx_lock));
1457 up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE;
1458 up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE;
1459 }
1460
1461 up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1462 up->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1463 pm_qos_add_request(&up->pm_qos_request,
1464 PM_QOS_CPU_DMA_LATENCY, up->latency);
1465 serial_omap_uart_wq = create_singlethread_workqueue(up->name);
1466 INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
1467
1468 pm_runtime_use_autosuspend(&pdev->dev);
1469 pm_runtime_set_autosuspend_delay(&pdev->dev,
1470 omap_up_info->autosuspend_timeout);
1471
1472 pm_runtime_irq_safe(&pdev->dev);
1473 pm_runtime_enable(&pdev->dev);
1474 pm_runtime_get_sync(&pdev->dev);
1475
1476 ui[up->port.line] = up;
1477 serial_omap_add_console_port(up);
1478
1479 ret = uart_add_one_port(&serial_omap_reg, &up->port);
1480 if (ret != 0)
1481 goto do_release_region;
1482
1483 pm_runtime_put(&pdev->dev);
1484 platform_set_drvdata(pdev, up);
1485 return 0;
1486 err:
1487 dev_err(&pdev->dev, "[UART%d]: failure [%s]: %d\n",
1488 pdev->id, __func__, ret);
1489 do_release_region:
1490 release_mem_region(mem->start, resource_size(mem));
1491 return ret;
1492 }
1493
1494 static int serial_omap_remove(struct platform_device *dev)
1495 {
1496 struct uart_omap_port *up = platform_get_drvdata(dev);
1497
1498 if (up) {
1499 pm_runtime_disable(&up->pdev->dev);
1500 uart_remove_one_port(&serial_omap_reg, &up->port);
1501 pm_qos_remove_request(&up->pm_qos_request);
1502
1503 kfree(up);
1504 }
1505
1506 platform_set_drvdata(dev, NULL);
1507 return 0;
1508 }
1509
1510 /*
1511 * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
1512 * The access to uart register after MDR1 Access
1513 * causes UART to corrupt data.
1514 *
1515 * Need a delay =
1516 * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
1517 * give 10 times as much
1518 */
1519 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
1520 {
1521 u8 timeout = 255;
1522
1523 serial_out(up, UART_OMAP_MDR1, mdr1);
1524 udelay(2);
1525 serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
1526 UART_FCR_CLEAR_RCVR);
1527 /*
1528 * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
1529 * TX_FIFO_E bit is 1.
1530 */
1531 while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
1532 (UART_LSR_THRE | UART_LSR_DR))) {
1533 timeout--;
1534 if (!timeout) {
1535 /* Should *never* happen. we warn and carry on */
1536 dev_crit(&up->pdev->dev, "Errata i202: timedout %x\n",
1537 serial_in(up, UART_LSR));
1538 break;
1539 }
1540 udelay(1);
1541 }
1542 }
1543
1544 #ifdef CONFIG_PM_RUNTIME
1545 static void serial_omap_restore_context(struct uart_omap_port *up)
1546 {
1547 if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1548 serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
1549 else
1550 serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1551
1552 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1553 serial_out(up, UART_EFR, UART_EFR_ECB);
1554 serial_out(up, UART_LCR, 0x0); /* Operational mode */
1555 serial_out(up, UART_IER, 0x0);
1556 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1557 serial_out(up, UART_DLL, up->dll);
1558 serial_out(up, UART_DLM, up->dlh);
1559 serial_out(up, UART_LCR, 0x0); /* Operational mode */
1560 serial_out(up, UART_IER, up->ier);
1561 serial_out(up, UART_FCR, up->fcr);
1562 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1563 serial_out(up, UART_MCR, up->mcr);
1564 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1565 serial_out(up, UART_OMAP_SCR, up->scr);
1566 serial_out(up, UART_EFR, up->efr);
1567 serial_out(up, UART_LCR, up->lcr);
1568 if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1569 serial_omap_mdr1_errataset(up, up->mdr1);
1570 else
1571 serial_out(up, UART_OMAP_MDR1, up->mdr1);
1572 }
1573
1574 static int serial_omap_runtime_suspend(struct device *dev)
1575 {
1576 struct uart_omap_port *up = dev_get_drvdata(dev);
1577 struct omap_uart_port_info *pdata = dev->platform_data;
1578
1579 if (!up)
1580 return -EINVAL;
1581
1582 if (!pdata || !pdata->enable_wakeup)
1583 return 0;
1584
1585 if (pdata->get_context_loss_count)
1586 up->context_loss_cnt = pdata->get_context_loss_count(dev);
1587
1588 if (device_may_wakeup(dev)) {
1589 if (!up->wakeups_enabled) {
1590 pdata->enable_wakeup(up->pdev, true);
1591 up->wakeups_enabled = true;
1592 }
1593 } else {
1594 if (up->wakeups_enabled) {
1595 pdata->enable_wakeup(up->pdev, false);
1596 up->wakeups_enabled = false;
1597 }
1598 }
1599
1600 /* Errata i291 */
1601 if (up->use_dma && pdata->set_forceidle &&
1602 (up->errata & UART_ERRATA_i291_DMA_FORCEIDLE))
1603 pdata->set_forceidle(up->pdev);
1604
1605 up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1606 schedule_work(&up->qos_work);
1607
1608 return 0;
1609 }
1610
1611 static int serial_omap_runtime_resume(struct device *dev)
1612 {
1613 struct uart_omap_port *up = dev_get_drvdata(dev);
1614 struct omap_uart_port_info *pdata = dev->platform_data;
1615
1616 if (up && pdata) {
1617 if (pdata->get_context_loss_count) {
1618 u32 loss_cnt = pdata->get_context_loss_count(dev);
1619
1620 if (up->context_loss_cnt != loss_cnt)
1621 serial_omap_restore_context(up);
1622 }
1623
1624 /* Errata i291 */
1625 if (up->use_dma && pdata->set_noidle &&
1626 (up->errata & UART_ERRATA_i291_DMA_FORCEIDLE))
1627 pdata->set_noidle(up->pdev);
1628
1629 up->latency = up->calc_latency;
1630 schedule_work(&up->qos_work);
1631 }
1632
1633 return 0;
1634 }
1635 #endif
1636
1637 static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1638 SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1639 SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1640 serial_omap_runtime_resume, NULL)
1641 };
1642
1643 #if defined(CONFIG_OF)
1644 static const struct of_device_id omap_serial_of_match[] = {
1645 { .compatible = "ti,omap2-uart" },
1646 { .compatible = "ti,omap3-uart" },
1647 { .compatible = "ti,omap4-uart" },
1648 {},
1649 };
1650 MODULE_DEVICE_TABLE(of, omap_serial_of_match);
1651 #endif
1652
1653 static struct platform_driver serial_omap_driver = {
1654 .probe = serial_omap_probe,
1655 .remove = serial_omap_remove,
1656 .driver = {
1657 .name = DRIVER_NAME,
1658 .pm = &serial_omap_dev_pm_ops,
1659 .of_match_table = of_match_ptr(omap_serial_of_match),
1660 },
1661 };
1662
1663 static int __init serial_omap_init(void)
1664 {
1665 int ret;
1666
1667 ret = uart_register_driver(&serial_omap_reg);
1668 if (ret != 0)
1669 return ret;
1670 ret = platform_driver_register(&serial_omap_driver);
1671 if (ret != 0)
1672 uart_unregister_driver(&serial_omap_reg);
1673 return ret;
1674 }
1675
1676 static void __exit serial_omap_exit(void)
1677 {
1678 platform_driver_unregister(&serial_omap_driver);
1679 uart_unregister_driver(&serial_omap_reg);
1680 }
1681
1682 module_init(serial_omap_init);
1683 module_exit(serial_omap_exit);
1684
1685 MODULE_DESCRIPTION("OMAP High Speed UART driver");
1686 MODULE_LICENSE("GPL");
1687 MODULE_AUTHOR("Texas Instruments Inc");