ARM: OMAP2+: UART: Ensure all reg values configured are available from port structure
[firefly-linux-kernel-4.4.55.git] / drivers / tty / serial / omap-serial.c
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
42 #include <plat/dma.h>
43 #include <plat/dmtimer.h>
44 #include <plat/omap-serial.h>
45
46 #define OMAP_UART_AUTOSUSPEND_DELAY -1
47
48 static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
49
50 /* Forward declaration of functions */
51 static void uart_tx_dma_callback(int lch, u16 ch_status, void *data);
52 static void serial_omap_rx_timeout(unsigned long uart_no);
53 static int serial_omap_start_rxdma(struct uart_omap_port *up);
54
55 static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
56 {
57         offset <<= up->port.regshift;
58         return readw(up->port.membase + offset);
59 }
60
61 static inline void serial_out(struct uart_omap_port *up, int offset, int value)
62 {
63         offset <<= up->port.regshift;
64         writew(value, up->port.membase + offset);
65 }
66
67 static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
68 {
69         serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
70         serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
71                        UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
72         serial_out(up, UART_FCR, 0);
73 }
74
75 /*
76  * serial_omap_get_divisor - calculate divisor value
77  * @port: uart port info
78  * @baud: baudrate for which divisor needs to be calculated.
79  *
80  * We have written our own function to get the divisor so as to support
81  * 13x mode. 3Mbps Baudrate as an different divisor.
82  * Reference OMAP TRM Chapter 17:
83  * Table 17-1. UART Mode Baud Rates, Divisor Values, and Error Rates
84  * referring to oversampling - divisor value
85  * baudrate 460,800 to 3,686,400 all have divisor 13
86  * except 3,000,000 which has divisor value 16
87  */
88 static unsigned int
89 serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
90 {
91         unsigned int divisor;
92
93         if (baud > OMAP_MODE13X_SPEED && baud != 3000000)
94                 divisor = 13;
95         else
96                 divisor = 16;
97         return port->uartclk/(baud * divisor);
98 }
99
100 static void serial_omap_stop_rxdma(struct uart_omap_port *up)
101 {
102         if (up->uart_dma.rx_dma_used) {
103                 del_timer(&up->uart_dma.rx_timer);
104                 omap_stop_dma(up->uart_dma.rx_dma_channel);
105                 omap_free_dma(up->uart_dma.rx_dma_channel);
106                 up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE;
107                 up->uart_dma.rx_dma_used = false;
108                 pm_runtime_mark_last_busy(&up->pdev->dev);
109                 pm_runtime_put_autosuspend(&up->pdev->dev);
110         }
111 }
112
113 static void serial_omap_enable_ms(struct uart_port *port)
114 {
115         struct uart_omap_port *up = (struct uart_omap_port *)port;
116
117         dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->pdev->id);
118
119         pm_runtime_get_sync(&up->pdev->dev);
120         up->ier |= UART_IER_MSI;
121         serial_out(up, UART_IER, up->ier);
122         pm_runtime_put(&up->pdev->dev);
123 }
124
125 static void serial_omap_stop_tx(struct uart_port *port)
126 {
127         struct uart_omap_port *up = (struct uart_omap_port *)port;
128
129         if (up->use_dma &&
130                 up->uart_dma.tx_dma_channel != OMAP_UART_DMA_CH_FREE) {
131                 /*
132                  * Check if dma is still active. If yes do nothing,
133                  * return. Else stop dma
134                  */
135                 if (omap_get_dma_active_status(up->uart_dma.tx_dma_channel))
136                         return;
137                 omap_stop_dma(up->uart_dma.tx_dma_channel);
138                 omap_free_dma(up->uart_dma.tx_dma_channel);
139                 up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE;
140                 pm_runtime_mark_last_busy(&up->pdev->dev);
141                 pm_runtime_put_autosuspend(&up->pdev->dev);
142         }
143
144         pm_runtime_get_sync(&up->pdev->dev);
145         if (up->ier & UART_IER_THRI) {
146                 up->ier &= ~UART_IER_THRI;
147                 serial_out(up, UART_IER, up->ier);
148         }
149
150         pm_runtime_mark_last_busy(&up->pdev->dev);
151         pm_runtime_put_autosuspend(&up->pdev->dev);
152 }
153
154 static void serial_omap_stop_rx(struct uart_port *port)
155 {
156         struct uart_omap_port *up = (struct uart_omap_port *)port;
157
158         pm_runtime_get_sync(&up->pdev->dev);
159         if (up->use_dma)
160                 serial_omap_stop_rxdma(up);
161         up->ier &= ~UART_IER_RLSI;
162         up->port.read_status_mask &= ~UART_LSR_DR;
163         serial_out(up, UART_IER, up->ier);
164         pm_runtime_mark_last_busy(&up->pdev->dev);
165         pm_runtime_put_autosuspend(&up->pdev->dev);
166 }
167
168 static inline void receive_chars(struct uart_omap_port *up, int *status)
169 {
170         struct tty_struct *tty = up->port.state->port.tty;
171         unsigned int flag;
172         unsigned char ch, lsr = *status;
173         int max_count = 256;
174
175         do {
176                 if (likely(lsr & UART_LSR_DR))
177                         ch = serial_in(up, UART_RX);
178                 flag = TTY_NORMAL;
179                 up->port.icount.rx++;
180
181                 if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) {
182                         /*
183                          * For statistics only
184                          */
185                         if (lsr & UART_LSR_BI) {
186                                 lsr &= ~(UART_LSR_FE | UART_LSR_PE);
187                                 up->port.icount.brk++;
188                                 /*
189                                  * We do the SysRQ and SAK checking
190                                  * here because otherwise the break
191                                  * may get masked by ignore_status_mask
192                                  * or read_status_mask.
193                                  */
194                                 if (uart_handle_break(&up->port))
195                                         goto ignore_char;
196                         } else if (lsr & UART_LSR_PE) {
197                                 up->port.icount.parity++;
198                         } else if (lsr & UART_LSR_FE) {
199                                 up->port.icount.frame++;
200                         }
201
202                         if (lsr & UART_LSR_OE)
203                                 up->port.icount.overrun++;
204
205                         /*
206                          * Mask off conditions which should be ignored.
207                          */
208                         lsr &= up->port.read_status_mask;
209
210 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
211                         if (up->port.line == up->port.cons->index) {
212                                 /* Recover the break flag from console xmit */
213                                 lsr |= up->lsr_break_flag;
214                         }
215 #endif
216                         if (lsr & UART_LSR_BI)
217                                 flag = TTY_BREAK;
218                         else if (lsr & UART_LSR_PE)
219                                 flag = TTY_PARITY;
220                         else if (lsr & UART_LSR_FE)
221                                 flag = TTY_FRAME;
222                 }
223
224                 if (uart_handle_sysrq_char(&up->port, ch))
225                         goto ignore_char;
226                 uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
227 ignore_char:
228                 lsr = serial_in(up, UART_LSR);
229         } while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (max_count-- > 0));
230         spin_unlock(&up->port.lock);
231         tty_flip_buffer_push(tty);
232         spin_lock(&up->port.lock);
233 }
234
235 static void transmit_chars(struct uart_omap_port *up)
236 {
237         struct circ_buf *xmit = &up->port.state->xmit;
238         int count;
239
240         if (up->port.x_char) {
241                 serial_out(up, UART_TX, up->port.x_char);
242                 up->port.icount.tx++;
243                 up->port.x_char = 0;
244                 return;
245         }
246         if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
247                 serial_omap_stop_tx(&up->port);
248                 return;
249         }
250         count = up->port.fifosize / 4;
251         do {
252                 serial_out(up, UART_TX, xmit->buf[xmit->tail]);
253                 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
254                 up->port.icount.tx++;
255                 if (uart_circ_empty(xmit))
256                         break;
257         } while (--count > 0);
258
259         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
260                 uart_write_wakeup(&up->port);
261
262         if (uart_circ_empty(xmit))
263                 serial_omap_stop_tx(&up->port);
264 }
265
266 static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
267 {
268         if (!(up->ier & UART_IER_THRI)) {
269                 up->ier |= UART_IER_THRI;
270                 serial_out(up, UART_IER, up->ier);
271         }
272 }
273
274 static void serial_omap_start_tx(struct uart_port *port)
275 {
276         struct uart_omap_port *up = (struct uart_omap_port *)port;
277         struct circ_buf *xmit;
278         unsigned int start;
279         int ret = 0;
280
281         if (!up->use_dma) {
282                 pm_runtime_get_sync(&up->pdev->dev);
283                 serial_omap_enable_ier_thri(up);
284                 pm_runtime_mark_last_busy(&up->pdev->dev);
285                 pm_runtime_put_autosuspend(&up->pdev->dev);
286                 return;
287         }
288
289         if (up->uart_dma.tx_dma_used)
290                 return;
291
292         xmit = &up->port.state->xmit;
293
294         if (up->uart_dma.tx_dma_channel == OMAP_UART_DMA_CH_FREE) {
295                 pm_runtime_get_sync(&up->pdev->dev);
296                 ret = omap_request_dma(up->uart_dma.uart_dma_tx,
297                                 "UART Tx DMA",
298                                 (void *)uart_tx_dma_callback, up,
299                                 &(up->uart_dma.tx_dma_channel));
300
301                 if (ret < 0) {
302                         serial_omap_enable_ier_thri(up);
303                         return;
304                 }
305         }
306         spin_lock(&(up->uart_dma.tx_lock));
307         up->uart_dma.tx_dma_used = true;
308         spin_unlock(&(up->uart_dma.tx_lock));
309
310         start = up->uart_dma.tx_buf_dma_phys +
311                                 (xmit->tail & (UART_XMIT_SIZE - 1));
312
313         up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit);
314         /*
315          * It is a circular buffer. See if the buffer has wounded back.
316          * If yes it will have to be transferred in two separate dma
317          * transfers
318          */
319         if (start + up->uart_dma.tx_buf_size >=
320                         up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE)
321                 up->uart_dma.tx_buf_size =
322                         (up->uart_dma.tx_buf_dma_phys +
323                         UART_XMIT_SIZE) - start;
324
325         omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0,
326                                 OMAP_DMA_AMODE_CONSTANT,
327                                 up->uart_dma.uart_base, 0, 0);
328         omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0,
329                                 OMAP_DMA_AMODE_POST_INC, start, 0, 0);
330         omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel,
331                                 OMAP_DMA_DATA_TYPE_S8,
332                                 up->uart_dma.tx_buf_size, 1,
333                                 OMAP_DMA_SYNC_ELEMENT,
334                                 up->uart_dma.uart_dma_tx, 0);
335         /* FIXME: Cache maintenance needed here? */
336         omap_start_dma(up->uart_dma.tx_dma_channel);
337 }
338
339 static unsigned int check_modem_status(struct uart_omap_port *up)
340 {
341         unsigned int status;
342
343         status = serial_in(up, UART_MSR);
344         status |= up->msr_saved_flags;
345         up->msr_saved_flags = 0;
346         if ((status & UART_MSR_ANY_DELTA) == 0)
347                 return status;
348
349         if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
350             up->port.state != NULL) {
351                 if (status & UART_MSR_TERI)
352                         up->port.icount.rng++;
353                 if (status & UART_MSR_DDSR)
354                         up->port.icount.dsr++;
355                 if (status & UART_MSR_DDCD)
356                         uart_handle_dcd_change
357                                 (&up->port, status & UART_MSR_DCD);
358                 if (status & UART_MSR_DCTS)
359                         uart_handle_cts_change
360                                 (&up->port, status & UART_MSR_CTS);
361                 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
362         }
363
364         return status;
365 }
366
367 /**
368  * serial_omap_irq() - This handles the interrupt from one port
369  * @irq: uart port irq number
370  * @dev_id: uart port info
371  */
372 static inline irqreturn_t serial_omap_irq(int irq, void *dev_id)
373 {
374         struct uart_omap_port *up = dev_id;
375         unsigned int iir, lsr;
376         unsigned long flags;
377
378         pm_runtime_get_sync(&up->pdev->dev);
379         iir = serial_in(up, UART_IIR);
380         if (iir & UART_IIR_NO_INT) {
381                 pm_runtime_mark_last_busy(&up->pdev->dev);
382                 pm_runtime_put_autosuspend(&up->pdev->dev);
383                 return IRQ_NONE;
384         }
385
386         spin_lock_irqsave(&up->port.lock, flags);
387         lsr = serial_in(up, UART_LSR);
388         if (iir & UART_IIR_RLSI) {
389                 if (!up->use_dma) {
390                         if (lsr & UART_LSR_DR)
391                                 receive_chars(up, &lsr);
392                 } else {
393                         up->ier &= ~(UART_IER_RDI | UART_IER_RLSI);
394                         serial_out(up, UART_IER, up->ier);
395                         if ((serial_omap_start_rxdma(up) != 0) &&
396                                         (lsr & UART_LSR_DR))
397                                 receive_chars(up, &lsr);
398                 }
399         }
400
401         check_modem_status(up);
402         if ((lsr & UART_LSR_THRE) && (iir & UART_IIR_THRI))
403                 transmit_chars(up);
404
405         spin_unlock_irqrestore(&up->port.lock, flags);
406         pm_runtime_mark_last_busy(&up->pdev->dev);
407         pm_runtime_put_autosuspend(&up->pdev->dev);
408
409         up->port_activity = jiffies;
410         return IRQ_HANDLED;
411 }
412
413 static unsigned int serial_omap_tx_empty(struct uart_port *port)
414 {
415         struct uart_omap_port *up = (struct uart_omap_port *)port;
416         unsigned long flags = 0;
417         unsigned int ret = 0;
418
419         pm_runtime_get_sync(&up->pdev->dev);
420         dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->pdev->id);
421         spin_lock_irqsave(&up->port.lock, flags);
422         ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
423         spin_unlock_irqrestore(&up->port.lock, flags);
424         pm_runtime_put(&up->pdev->dev);
425         return ret;
426 }
427
428 static unsigned int serial_omap_get_mctrl(struct uart_port *port)
429 {
430         struct uart_omap_port *up = (struct uart_omap_port *)port;
431         unsigned char status;
432         unsigned int ret = 0;
433
434         pm_runtime_get_sync(&up->pdev->dev);
435         status = check_modem_status(up);
436         pm_runtime_put(&up->pdev->dev);
437
438         dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->pdev->id);
439
440         if (status & UART_MSR_DCD)
441                 ret |= TIOCM_CAR;
442         if (status & UART_MSR_RI)
443                 ret |= TIOCM_RNG;
444         if (status & UART_MSR_DSR)
445                 ret |= TIOCM_DSR;
446         if (status & UART_MSR_CTS)
447                 ret |= TIOCM_CTS;
448         return ret;
449 }
450
451 static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
452 {
453         struct uart_omap_port *up = (struct uart_omap_port *)port;
454         unsigned char mcr = 0;
455
456         dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->pdev->id);
457         if (mctrl & TIOCM_RTS)
458                 mcr |= UART_MCR_RTS;
459         if (mctrl & TIOCM_DTR)
460                 mcr |= UART_MCR_DTR;
461         if (mctrl & TIOCM_OUT1)
462                 mcr |= UART_MCR_OUT1;
463         if (mctrl & TIOCM_OUT2)
464                 mcr |= UART_MCR_OUT2;
465         if (mctrl & TIOCM_LOOP)
466                 mcr |= UART_MCR_LOOP;
467
468         pm_runtime_get_sync(&up->pdev->dev);
469         up->mcr = serial_in(up, UART_MCR);
470         up->mcr |= mcr;
471         serial_out(up, UART_MCR, up->mcr);
472         pm_runtime_put(&up->pdev->dev);
473 }
474
475 static void serial_omap_break_ctl(struct uart_port *port, int break_state)
476 {
477         struct uart_omap_port *up = (struct uart_omap_port *)port;
478         unsigned long flags = 0;
479
480         dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->pdev->id);
481         pm_runtime_get_sync(&up->pdev->dev);
482         spin_lock_irqsave(&up->port.lock, flags);
483         if (break_state == -1)
484                 up->lcr |= UART_LCR_SBC;
485         else
486                 up->lcr &= ~UART_LCR_SBC;
487         serial_out(up, UART_LCR, up->lcr);
488         spin_unlock_irqrestore(&up->port.lock, flags);
489         pm_runtime_put(&up->pdev->dev);
490 }
491
492 static int serial_omap_startup(struct uart_port *port)
493 {
494         struct uart_omap_port *up = (struct uart_omap_port *)port;
495         unsigned long flags = 0;
496         int retval;
497
498         /*
499          * Allocate the IRQ
500          */
501         retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
502                                 up->name, up);
503         if (retval)
504                 return retval;
505
506         dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->pdev->id);
507
508         pm_runtime_get_sync(&up->pdev->dev);
509         /*
510          * Clear the FIFO buffers and disable them.
511          * (they will be reenabled in set_termios())
512          */
513         serial_omap_clear_fifos(up);
514         /* For Hardware flow control */
515         serial_out(up, UART_MCR, UART_MCR_RTS);
516
517         /*
518          * Clear the interrupt registers.
519          */
520         (void) serial_in(up, UART_LSR);
521         if (serial_in(up, UART_LSR) & UART_LSR_DR)
522                 (void) serial_in(up, UART_RX);
523         (void) serial_in(up, UART_IIR);
524         (void) serial_in(up, UART_MSR);
525
526         /*
527          * Now, initialize the UART
528          */
529         serial_out(up, UART_LCR, UART_LCR_WLEN8);
530         spin_lock_irqsave(&up->port.lock, flags);
531         /*
532          * Most PC uarts need OUT2 raised to enable interrupts.
533          */
534         up->port.mctrl |= TIOCM_OUT2;
535         serial_omap_set_mctrl(&up->port, up->port.mctrl);
536         spin_unlock_irqrestore(&up->port.lock, flags);
537
538         up->msr_saved_flags = 0;
539         if (up->use_dma) {
540                 free_page((unsigned long)up->port.state->xmit.buf);
541                 up->port.state->xmit.buf = dma_alloc_coherent(NULL,
542                         UART_XMIT_SIZE,
543                         (dma_addr_t *)&(up->uart_dma.tx_buf_dma_phys),
544                         0);
545                 init_timer(&(up->uart_dma.rx_timer));
546                 up->uart_dma.rx_timer.function = serial_omap_rx_timeout;
547                 up->uart_dma.rx_timer.data = up->pdev->id;
548                 /* Currently the buffer size is 4KB. Can increase it */
549                 up->uart_dma.rx_buf = dma_alloc_coherent(NULL,
550                         up->uart_dma.rx_buf_size,
551                         (dma_addr_t *)&(up->uart_dma.rx_buf_dma_phys), 0);
552         }
553         /*
554          * Finally, enable interrupts. Note: Modem status interrupts
555          * are set via set_termios(), which will be occurring imminently
556          * anyway, so we don't enable them here.
557          */
558         up->ier = UART_IER_RLSI | UART_IER_RDI;
559         serial_out(up, UART_IER, up->ier);
560
561         /* Enable module level wake up */
562         serial_out(up, UART_OMAP_WER, OMAP_UART_WER_MOD_WKUP);
563
564         pm_runtime_mark_last_busy(&up->pdev->dev);
565         pm_runtime_put_autosuspend(&up->pdev->dev);
566         up->port_activity = jiffies;
567         return 0;
568 }
569
570 static void serial_omap_shutdown(struct uart_port *port)
571 {
572         struct uart_omap_port *up = (struct uart_omap_port *)port;
573         unsigned long flags = 0;
574
575         dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->pdev->id);
576
577         pm_runtime_get_sync(&up->pdev->dev);
578         /*
579          * Disable interrupts from this port
580          */
581         up->ier = 0;
582         serial_out(up, UART_IER, 0);
583
584         spin_lock_irqsave(&up->port.lock, flags);
585         up->port.mctrl &= ~TIOCM_OUT2;
586         serial_omap_set_mctrl(&up->port, up->port.mctrl);
587         spin_unlock_irqrestore(&up->port.lock, flags);
588
589         /*
590          * Disable break condition and FIFOs
591          */
592         serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
593         serial_omap_clear_fifos(up);
594
595         /*
596          * Read data port to reset things, and then free the irq
597          */
598         if (serial_in(up, UART_LSR) & UART_LSR_DR)
599                 (void) serial_in(up, UART_RX);
600         if (up->use_dma) {
601                 dma_free_coherent(up->port.dev,
602                         UART_XMIT_SIZE, up->port.state->xmit.buf,
603                         up->uart_dma.tx_buf_dma_phys);
604                 up->port.state->xmit.buf = NULL;
605                 serial_omap_stop_rx(port);
606                 dma_free_coherent(up->port.dev,
607                         up->uart_dma.rx_buf_size, up->uart_dma.rx_buf,
608                         up->uart_dma.rx_buf_dma_phys);
609                 up->uart_dma.rx_buf = NULL;
610         }
611
612         pm_runtime_put(&up->pdev->dev);
613         free_irq(up->port.irq, up);
614 }
615
616 static inline void
617 serial_omap_configure_xonxoff
618                 (struct uart_omap_port *up, struct ktermios *termios)
619 {
620         up->lcr = serial_in(up, UART_LCR);
621         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
622         up->efr = serial_in(up, UART_EFR);
623         serial_out(up, UART_EFR, up->efr & ~UART_EFR_ECB);
624
625         serial_out(up, UART_XON1, termios->c_cc[VSTART]);
626         serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
627
628         /* clear SW control mode bits */
629         up->efr &= OMAP_UART_SW_CLR;
630
631         /*
632          * IXON Flag:
633          * Enable XON/XOFF flow control on output.
634          * Transmit XON1, XOFF1
635          */
636         if (termios->c_iflag & IXON)
637                 up->efr |= OMAP_UART_SW_TX;
638
639         /*
640          * IXOFF Flag:
641          * Enable XON/XOFF flow control on input.
642          * Receiver compares XON1, XOFF1.
643          */
644         if (termios->c_iflag & IXOFF)
645                 up->efr |= OMAP_UART_SW_RX;
646
647         serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
648         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
649
650         up->mcr = serial_in(up, UART_MCR);
651
652         /*
653          * IXANY Flag:
654          * Enable any character to restart output.
655          * Operation resumes after receiving any
656          * character after recognition of the XOFF character
657          */
658         if (termios->c_iflag & IXANY)
659                 up->mcr |= UART_MCR_XONANY;
660
661         serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
662         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
663         serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
664         /* Enable special char function UARTi.EFR_REG[5] and
665          * load the new software flow control mode IXON or IXOFF
666          * and restore the UARTi.EFR_REG[4] ENHANCED_EN value.
667          */
668         serial_out(up, UART_EFR, up->efr | UART_EFR_SCD);
669         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
670
671         serial_out(up, UART_MCR, up->mcr & ~UART_MCR_TCRTLR);
672         serial_out(up, UART_LCR, up->lcr);
673 }
674
675 static void
676 serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
677                         struct ktermios *old)
678 {
679         struct uart_omap_port *up = (struct uart_omap_port *)port;
680         unsigned char cval = 0;
681         unsigned char efr = 0;
682         unsigned long flags = 0;
683         unsigned int baud, quot;
684
685         switch (termios->c_cflag & CSIZE) {
686         case CS5:
687                 cval = UART_LCR_WLEN5;
688                 break;
689         case CS6:
690                 cval = UART_LCR_WLEN6;
691                 break;
692         case CS7:
693                 cval = UART_LCR_WLEN7;
694                 break;
695         default:
696         case CS8:
697                 cval = UART_LCR_WLEN8;
698                 break;
699         }
700
701         if (termios->c_cflag & CSTOPB)
702                 cval |= UART_LCR_STOP;
703         if (termios->c_cflag & PARENB)
704                 cval |= UART_LCR_PARITY;
705         if (!(termios->c_cflag & PARODD))
706                 cval |= UART_LCR_EPAR;
707
708         /*
709          * Ask the core to calculate the divisor for us.
710          */
711
712         baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
713         quot = serial_omap_get_divisor(port, baud);
714
715         up->dll = quot & 0xff;
716         up->dlh = quot >> 8;
717         up->mdr1 = UART_OMAP_MDR1_DISABLE;
718
719         up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
720                         UART_FCR_ENABLE_FIFO;
721         if (up->use_dma)
722                 up->fcr |= UART_FCR_DMA_SELECT;
723
724         /*
725          * Ok, we're now changing the port state. Do it with
726          * interrupts disabled.
727          */
728         pm_runtime_get_sync(&up->pdev->dev);
729         spin_lock_irqsave(&up->port.lock, flags);
730
731         /*
732          * Update the per-port timeout.
733          */
734         uart_update_timeout(port, termios->c_cflag, baud);
735
736         up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
737         if (termios->c_iflag & INPCK)
738                 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
739         if (termios->c_iflag & (BRKINT | PARMRK))
740                 up->port.read_status_mask |= UART_LSR_BI;
741
742         /*
743          * Characters to ignore
744          */
745         up->port.ignore_status_mask = 0;
746         if (termios->c_iflag & IGNPAR)
747                 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
748         if (termios->c_iflag & IGNBRK) {
749                 up->port.ignore_status_mask |= UART_LSR_BI;
750                 /*
751                  * If we're ignoring parity and break indicators,
752                  * ignore overruns too (for real raw support).
753                  */
754                 if (termios->c_iflag & IGNPAR)
755                         up->port.ignore_status_mask |= UART_LSR_OE;
756         }
757
758         /*
759          * ignore all characters if CREAD is not set
760          */
761         if ((termios->c_cflag & CREAD) == 0)
762                 up->port.ignore_status_mask |= UART_LSR_DR;
763
764         /*
765          * Modem status interrupts
766          */
767         up->ier &= ~UART_IER_MSI;
768         if (UART_ENABLE_MS(&up->port, termios->c_cflag))
769                 up->ier |= UART_IER_MSI;
770         serial_out(up, UART_IER, up->ier);
771         serial_out(up, UART_LCR, cval);         /* reset DLAB */
772         up->lcr = cval;
773
774         /* FIFOs and DMA Settings */
775
776         /* FCR can be changed only when the
777          * baud clock is not running
778          * DLL_REG and DLH_REG set to 0.
779          */
780         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
781         serial_out(up, UART_DLL, 0);
782         serial_out(up, UART_DLM, 0);
783         serial_out(up, UART_LCR, 0);
784
785         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
786
787         up->efr = serial_in(up, UART_EFR);
788         serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
789
790         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
791         up->mcr = serial_in(up, UART_MCR);
792         serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
793         /* FIFO ENABLE, DMA MODE */
794         serial_out(up, UART_FCR, up->fcr);
795         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
796
797         if (up->use_dma) {
798                 serial_out(up, UART_TI752_TLR, 0);
799                 up->scr |= (UART_FCR_TRIGGER_4 | UART_FCR_TRIGGER_8);
800         }
801
802         serial_out(up, UART_OMAP_SCR, up->scr);
803
804         serial_out(up, UART_EFR, up->efr);
805         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
806         serial_out(up, UART_MCR, up->mcr);
807
808         /* Protocol, Baud Rate, and Interrupt Settings */
809
810         serial_out(up, UART_OMAP_MDR1, up->mdr1);
811         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
812
813         up->efr = serial_in(up, UART_EFR);
814         serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
815
816         serial_out(up, UART_LCR, 0);
817         serial_out(up, UART_IER, 0);
818         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
819
820         serial_out(up, UART_DLL, up->dll);      /* LS of divisor */
821         serial_out(up, UART_DLM, up->dlh);      /* MS of divisor */
822
823         serial_out(up, UART_LCR, 0);
824         serial_out(up, UART_IER, up->ier);
825         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
826
827         serial_out(up, UART_EFR, up->efr);
828         serial_out(up, UART_LCR, cval);
829
830         if (baud > 230400 && baud != 3000000)
831                 up->mdr1 = UART_OMAP_MDR1_13X_MODE;
832         else
833                 up->mdr1 = UART_OMAP_MDR1_16X_MODE;
834
835         serial_out(up, UART_OMAP_MDR1, up->mdr1);
836
837         /* Hardware Flow Control Configuration */
838
839         if (termios->c_cflag & CRTSCTS) {
840                 efr |= (UART_EFR_CTS | UART_EFR_RTS);
841                 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
842
843                 up->mcr = serial_in(up, UART_MCR);
844                 serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
845
846                 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
847                 up->efr = serial_in(up, UART_EFR);
848                 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
849
850                 serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
851                 serial_out(up, UART_EFR, efr); /* Enable AUTORTS and AUTOCTS */
852                 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
853                 serial_out(up, UART_MCR, up->mcr | UART_MCR_RTS);
854                 serial_out(up, UART_LCR, cval);
855         }
856
857         serial_omap_set_mctrl(&up->port, up->port.mctrl);
858         /* Software Flow Control Configuration */
859         serial_omap_configure_xonxoff(up, termios);
860
861         spin_unlock_irqrestore(&up->port.lock, flags);
862         pm_runtime_put(&up->pdev->dev);
863         dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->pdev->id);
864 }
865
866 static void
867 serial_omap_pm(struct uart_port *port, unsigned int state,
868                unsigned int oldstate)
869 {
870         struct uart_omap_port *up = (struct uart_omap_port *)port;
871         unsigned char efr;
872
873         dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->pdev->id);
874
875         pm_runtime_get_sync(&up->pdev->dev);
876         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
877         efr = serial_in(up, UART_EFR);
878         serial_out(up, UART_EFR, efr | UART_EFR_ECB);
879         serial_out(up, UART_LCR, 0);
880
881         serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
882         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
883         serial_out(up, UART_EFR, efr);
884         serial_out(up, UART_LCR, 0);
885
886         if (!device_may_wakeup(&up->pdev->dev)) {
887                 if (!state)
888                         pm_runtime_forbid(&up->pdev->dev);
889                 else
890                         pm_runtime_allow(&up->pdev->dev);
891         }
892
893         pm_runtime_put(&up->pdev->dev);
894 }
895
896 static void serial_omap_release_port(struct uart_port *port)
897 {
898         dev_dbg(port->dev, "serial_omap_release_port+\n");
899 }
900
901 static int serial_omap_request_port(struct uart_port *port)
902 {
903         dev_dbg(port->dev, "serial_omap_request_port+\n");
904         return 0;
905 }
906
907 static void serial_omap_config_port(struct uart_port *port, int flags)
908 {
909         struct uart_omap_port *up = (struct uart_omap_port *)port;
910
911         dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
912                                                         up->pdev->id);
913         up->port.type = PORT_OMAP;
914 }
915
916 static int
917 serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
918 {
919         /* we don't want the core code to modify any port params */
920         dev_dbg(port->dev, "serial_omap_verify_port+\n");
921         return -EINVAL;
922 }
923
924 static const char *
925 serial_omap_type(struct uart_port *port)
926 {
927         struct uart_omap_port *up = (struct uart_omap_port *)port;
928
929         dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->pdev->id);
930         return up->name;
931 }
932
933 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
934
935 static inline void wait_for_xmitr(struct uart_omap_port *up)
936 {
937         unsigned int status, tmout = 10000;
938
939         /* Wait up to 10ms for the character(s) to be sent. */
940         do {
941                 status = serial_in(up, UART_LSR);
942
943                 if (status & UART_LSR_BI)
944                         up->lsr_break_flag = UART_LSR_BI;
945
946                 if (--tmout == 0)
947                         break;
948                 udelay(1);
949         } while ((status & BOTH_EMPTY) != BOTH_EMPTY);
950
951         /* Wait up to 1s for flow control if necessary */
952         if (up->port.flags & UPF_CONS_FLOW) {
953                 tmout = 1000000;
954                 for (tmout = 1000000; tmout; tmout--) {
955                         unsigned int msr = serial_in(up, UART_MSR);
956
957                         up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
958                         if (msr & UART_MSR_CTS)
959                                 break;
960
961                         udelay(1);
962                 }
963         }
964 }
965
966 #ifdef CONFIG_CONSOLE_POLL
967
968 static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
969 {
970         struct uart_omap_port *up = (struct uart_omap_port *)port;
971
972         pm_runtime_get_sync(&up->pdev->dev);
973         wait_for_xmitr(up);
974         serial_out(up, UART_TX, ch);
975         pm_runtime_put(&up->pdev->dev);
976 }
977
978 static int serial_omap_poll_get_char(struct uart_port *port)
979 {
980         struct uart_omap_port *up = (struct uart_omap_port *)port;
981         unsigned int status;
982
983         pm_runtime_get_sync(&up->pdev->dev);
984         status = serial_in(up, UART_LSR);
985         if (!(status & UART_LSR_DR))
986                 return NO_POLL_CHAR;
987
988         status = serial_in(up, UART_RX);
989         pm_runtime_put(&up->pdev->dev);
990         return status;
991 }
992
993 #endif /* CONFIG_CONSOLE_POLL */
994
995 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
996
997 static struct uart_omap_port *serial_omap_console_ports[4];
998
999 static struct uart_driver serial_omap_reg;
1000
1001 static void serial_omap_console_putchar(struct uart_port *port, int ch)
1002 {
1003         struct uart_omap_port *up = (struct uart_omap_port *)port;
1004
1005         wait_for_xmitr(up);
1006         serial_out(up, UART_TX, ch);
1007 }
1008
1009 static void
1010 serial_omap_console_write(struct console *co, const char *s,
1011                 unsigned int count)
1012 {
1013         struct uart_omap_port *up = serial_omap_console_ports[co->index];
1014         unsigned long flags;
1015         unsigned int ier;
1016         int locked = 1;
1017
1018         pm_runtime_get_sync(&up->pdev->dev);
1019
1020         local_irq_save(flags);
1021         if (up->port.sysrq)
1022                 locked = 0;
1023         else if (oops_in_progress)
1024                 locked = spin_trylock(&up->port.lock);
1025         else
1026                 spin_lock(&up->port.lock);
1027
1028         /*
1029          * First save the IER then disable the interrupts
1030          */
1031         ier = serial_in(up, UART_IER);
1032         serial_out(up, UART_IER, 0);
1033
1034         uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1035
1036         /*
1037          * Finally, wait for transmitter to become empty
1038          * and restore the IER
1039          */
1040         wait_for_xmitr(up);
1041         serial_out(up, UART_IER, ier);
1042         /*
1043          * The receive handling will happen properly because the
1044          * receive ready bit will still be set; it is not cleared
1045          * on read.  However, modem control will not, we must
1046          * call it if we have saved something in the saved flags
1047          * while processing with interrupts off.
1048          */
1049         if (up->msr_saved_flags)
1050                 check_modem_status(up);
1051
1052         pm_runtime_mark_last_busy(&up->pdev->dev);
1053         pm_runtime_put_autosuspend(&up->pdev->dev);
1054         if (locked)
1055                 spin_unlock(&up->port.lock);
1056         local_irq_restore(flags);
1057 }
1058
1059 static int __init
1060 serial_omap_console_setup(struct console *co, char *options)
1061 {
1062         struct uart_omap_port *up;
1063         int baud = 115200;
1064         int bits = 8;
1065         int parity = 'n';
1066         int flow = 'n';
1067
1068         if (serial_omap_console_ports[co->index] == NULL)
1069                 return -ENODEV;
1070         up = serial_omap_console_ports[co->index];
1071
1072         if (options)
1073                 uart_parse_options(options, &baud, &parity, &bits, &flow);
1074
1075         return uart_set_options(&up->port, co, baud, parity, bits, flow);
1076 }
1077
1078 static struct console serial_omap_console = {
1079         .name           = OMAP_SERIAL_NAME,
1080         .write          = serial_omap_console_write,
1081         .device         = uart_console_device,
1082         .setup          = serial_omap_console_setup,
1083         .flags          = CON_PRINTBUFFER,
1084         .index          = -1,
1085         .data           = &serial_omap_reg,
1086 };
1087
1088 static void serial_omap_add_console_port(struct uart_omap_port *up)
1089 {
1090         serial_omap_console_ports[up->pdev->id] = up;
1091 }
1092
1093 #define OMAP_CONSOLE    (&serial_omap_console)
1094
1095 #else
1096
1097 #define OMAP_CONSOLE    NULL
1098
1099 static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1100 {}
1101
1102 #endif
1103
1104 static struct uart_ops serial_omap_pops = {
1105         .tx_empty       = serial_omap_tx_empty,
1106         .set_mctrl      = serial_omap_set_mctrl,
1107         .get_mctrl      = serial_omap_get_mctrl,
1108         .stop_tx        = serial_omap_stop_tx,
1109         .start_tx       = serial_omap_start_tx,
1110         .stop_rx        = serial_omap_stop_rx,
1111         .enable_ms      = serial_omap_enable_ms,
1112         .break_ctl      = serial_omap_break_ctl,
1113         .startup        = serial_omap_startup,
1114         .shutdown       = serial_omap_shutdown,
1115         .set_termios    = serial_omap_set_termios,
1116         .pm             = serial_omap_pm,
1117         .type           = serial_omap_type,
1118         .release_port   = serial_omap_release_port,
1119         .request_port   = serial_omap_request_port,
1120         .config_port    = serial_omap_config_port,
1121         .verify_port    = serial_omap_verify_port,
1122 #ifdef CONFIG_CONSOLE_POLL
1123         .poll_put_char  = serial_omap_poll_put_char,
1124         .poll_get_char  = serial_omap_poll_get_char,
1125 #endif
1126 };
1127
1128 static struct uart_driver serial_omap_reg = {
1129         .owner          = THIS_MODULE,
1130         .driver_name    = "OMAP-SERIAL",
1131         .dev_name       = OMAP_SERIAL_NAME,
1132         .nr             = OMAP_MAX_HSUART_PORTS,
1133         .cons           = OMAP_CONSOLE,
1134 };
1135
1136 #ifdef CONFIG_SUSPEND
1137 static int serial_omap_suspend(struct device *dev)
1138 {
1139         struct uart_omap_port *up = dev_get_drvdata(dev);
1140
1141         if (up)
1142                 uart_suspend_port(&serial_omap_reg, &up->port);
1143         return 0;
1144 }
1145
1146 static int serial_omap_resume(struct device *dev)
1147 {
1148         struct uart_omap_port *up = dev_get_drvdata(dev);
1149
1150         if (up)
1151                 uart_resume_port(&serial_omap_reg, &up->port);
1152         return 0;
1153 }
1154 #endif
1155
1156 static void serial_omap_rx_timeout(unsigned long uart_no)
1157 {
1158         struct uart_omap_port *up = ui[uart_no];
1159         unsigned int curr_dma_pos, curr_transmitted_size;
1160         int ret = 0;
1161
1162         curr_dma_pos = omap_get_dma_dst_pos(up->uart_dma.rx_dma_channel);
1163         if ((curr_dma_pos == up->uart_dma.prev_rx_dma_pos) ||
1164                              (curr_dma_pos == 0)) {
1165                 if (jiffies_to_msecs(jiffies - up->port_activity) <
1166                                                         RX_TIMEOUT) {
1167                         mod_timer(&up->uart_dma.rx_timer, jiffies +
1168                                 usecs_to_jiffies(up->uart_dma.rx_timeout));
1169                 } else {
1170                         serial_omap_stop_rxdma(up);
1171                         up->ier |= (UART_IER_RDI | UART_IER_RLSI);
1172                         serial_out(up, UART_IER, up->ier);
1173                 }
1174                 return;
1175         }
1176
1177         curr_transmitted_size = curr_dma_pos -
1178                                         up->uart_dma.prev_rx_dma_pos;
1179         up->port.icount.rx += curr_transmitted_size;
1180         tty_insert_flip_string(up->port.state->port.tty,
1181                         up->uart_dma.rx_buf +
1182                         (up->uart_dma.prev_rx_dma_pos -
1183                         up->uart_dma.rx_buf_dma_phys),
1184                         curr_transmitted_size);
1185         tty_flip_buffer_push(up->port.state->port.tty);
1186         up->uart_dma.prev_rx_dma_pos = curr_dma_pos;
1187         if (up->uart_dma.rx_buf_size +
1188                         up->uart_dma.rx_buf_dma_phys == curr_dma_pos) {
1189                 ret = serial_omap_start_rxdma(up);
1190                 if (ret < 0) {
1191                         serial_omap_stop_rxdma(up);
1192                         up->ier |= (UART_IER_RDI | UART_IER_RLSI);
1193                         serial_out(up, UART_IER, up->ier);
1194                 }
1195         } else  {
1196                 mod_timer(&up->uart_dma.rx_timer, jiffies +
1197                         usecs_to_jiffies(up->uart_dma.rx_timeout));
1198         }
1199         up->port_activity = jiffies;
1200 }
1201
1202 static void uart_rx_dma_callback(int lch, u16 ch_status, void *data)
1203 {
1204         return;
1205 }
1206
1207 static int serial_omap_start_rxdma(struct uart_omap_port *up)
1208 {
1209         int ret = 0;
1210
1211         if (up->uart_dma.rx_dma_channel == -1) {
1212                 pm_runtime_get_sync(&up->pdev->dev);
1213                 ret = omap_request_dma(up->uart_dma.uart_dma_rx,
1214                                 "UART Rx DMA",
1215                                 (void *)uart_rx_dma_callback, up,
1216                                 &(up->uart_dma.rx_dma_channel));
1217                 if (ret < 0)
1218                         return ret;
1219
1220                 omap_set_dma_src_params(up->uart_dma.rx_dma_channel, 0,
1221                                 OMAP_DMA_AMODE_CONSTANT,
1222                                 up->uart_dma.uart_base, 0, 0);
1223                 omap_set_dma_dest_params(up->uart_dma.rx_dma_channel, 0,
1224                                 OMAP_DMA_AMODE_POST_INC,
1225                                 up->uart_dma.rx_buf_dma_phys, 0, 0);
1226                 omap_set_dma_transfer_params(up->uart_dma.rx_dma_channel,
1227                                 OMAP_DMA_DATA_TYPE_S8,
1228                                 up->uart_dma.rx_buf_size, 1,
1229                                 OMAP_DMA_SYNC_ELEMENT,
1230                                 up->uart_dma.uart_dma_rx, 0);
1231         }
1232         up->uart_dma.prev_rx_dma_pos = up->uart_dma.rx_buf_dma_phys;
1233         /* FIXME: Cache maintenance needed here? */
1234         omap_start_dma(up->uart_dma.rx_dma_channel);
1235         mod_timer(&up->uart_dma.rx_timer, jiffies +
1236                                 usecs_to_jiffies(up->uart_dma.rx_timeout));
1237         up->uart_dma.rx_dma_used = true;
1238         return ret;
1239 }
1240
1241 static void serial_omap_continue_tx(struct uart_omap_port *up)
1242 {
1243         struct circ_buf *xmit = &up->port.state->xmit;
1244         unsigned int start = up->uart_dma.tx_buf_dma_phys
1245                         + (xmit->tail & (UART_XMIT_SIZE - 1));
1246
1247         if (uart_circ_empty(xmit))
1248                 return;
1249
1250         up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit);
1251         /*
1252          * It is a circular buffer. See if the buffer has wounded back.
1253          * If yes it will have to be transferred in two separate dma
1254          * transfers
1255          */
1256         if (start + up->uart_dma.tx_buf_size >=
1257                         up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE)
1258                 up->uart_dma.tx_buf_size =
1259                         (up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE) - start;
1260         omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0,
1261                                 OMAP_DMA_AMODE_CONSTANT,
1262                                 up->uart_dma.uart_base, 0, 0);
1263         omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0,
1264                                 OMAP_DMA_AMODE_POST_INC, start, 0, 0);
1265         omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel,
1266                                 OMAP_DMA_DATA_TYPE_S8,
1267                                 up->uart_dma.tx_buf_size, 1,
1268                                 OMAP_DMA_SYNC_ELEMENT,
1269                                 up->uart_dma.uart_dma_tx, 0);
1270         /* FIXME: Cache maintenance needed here? */
1271         omap_start_dma(up->uart_dma.tx_dma_channel);
1272 }
1273
1274 static void uart_tx_dma_callback(int lch, u16 ch_status, void *data)
1275 {
1276         struct uart_omap_port *up = (struct uart_omap_port *)data;
1277         struct circ_buf *xmit = &up->port.state->xmit;
1278
1279         xmit->tail = (xmit->tail + up->uart_dma.tx_buf_size) & \
1280                         (UART_XMIT_SIZE - 1);
1281         up->port.icount.tx += up->uart_dma.tx_buf_size;
1282
1283         if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1284                 uart_write_wakeup(&up->port);
1285
1286         if (uart_circ_empty(xmit)) {
1287                 spin_lock(&(up->uart_dma.tx_lock));
1288                 serial_omap_stop_tx(&up->port);
1289                 up->uart_dma.tx_dma_used = false;
1290                 spin_unlock(&(up->uart_dma.tx_lock));
1291         } else {
1292                 omap_stop_dma(up->uart_dma.tx_dma_channel);
1293                 serial_omap_continue_tx(up);
1294         }
1295         up->port_activity = jiffies;
1296         return;
1297 }
1298
1299 static int serial_omap_probe(struct platform_device *pdev)
1300 {
1301         struct uart_omap_port   *up;
1302         struct resource         *mem, *irq, *dma_tx, *dma_rx;
1303         struct omap_uart_port_info *omap_up_info = pdev->dev.platform_data;
1304         int ret = -ENOSPC;
1305
1306         mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1307         if (!mem) {
1308                 dev_err(&pdev->dev, "no mem resource?\n");
1309                 return -ENODEV;
1310         }
1311
1312         irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1313         if (!irq) {
1314                 dev_err(&pdev->dev, "no irq resource?\n");
1315                 return -ENODEV;
1316         }
1317
1318         if (!request_mem_region(mem->start, resource_size(mem),
1319                                 pdev->dev.driver->name)) {
1320                 dev_err(&pdev->dev, "memory region already claimed\n");
1321                 return -EBUSY;
1322         }
1323
1324         dma_rx = platform_get_resource_byname(pdev, IORESOURCE_DMA, "rx");
1325         if (!dma_rx) {
1326                 ret = -EINVAL;
1327                 goto err;
1328         }
1329
1330         dma_tx = platform_get_resource_byname(pdev, IORESOURCE_DMA, "tx");
1331         if (!dma_tx) {
1332                 ret = -EINVAL;
1333                 goto err;
1334         }
1335
1336         up = kzalloc(sizeof(*up), GFP_KERNEL);
1337         if (up == NULL) {
1338                 ret = -ENOMEM;
1339                 goto do_release_region;
1340         }
1341         sprintf(up->name, "OMAP UART%d", pdev->id);
1342         up->pdev = pdev;
1343         up->port.dev = &pdev->dev;
1344         up->port.type = PORT_OMAP;
1345         up->port.iotype = UPIO_MEM;
1346         up->port.irq = irq->start;
1347
1348         up->port.regshift = 2;
1349         up->port.fifosize = 64;
1350         up->port.ops = &serial_omap_pops;
1351         up->port.line = pdev->id;
1352
1353         up->port.mapbase = mem->start;
1354         up->port.membase = ioremap(mem->start, resource_size(mem));
1355         if (!up->port.membase) {
1356                 dev_err(&pdev->dev, "can't ioremap UART\n");
1357                 ret = -ENOMEM;
1358                 goto err;
1359         }
1360
1361         up->port.flags = omap_up_info->flags;
1362         up->port.uartclk = omap_up_info->uartclk;
1363         up->uart_dma.uart_base = mem->start;
1364
1365         if (omap_up_info->dma_enabled) {
1366                 up->uart_dma.uart_dma_tx = dma_tx->start;
1367                 up->uart_dma.uart_dma_rx = dma_rx->start;
1368                 up->use_dma = 1;
1369                 up->uart_dma.rx_buf_size = 4096;
1370                 up->uart_dma.rx_timeout = 2;
1371                 spin_lock_init(&(up->uart_dma.tx_lock));
1372                 spin_lock_init(&(up->uart_dma.rx_lock));
1373                 up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE;
1374                 up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE;
1375         }
1376
1377         pm_runtime_use_autosuspend(&pdev->dev);
1378         pm_runtime_set_autosuspend_delay(&pdev->dev,
1379                         OMAP_UART_AUTOSUSPEND_DELAY);
1380
1381         pm_runtime_irq_safe(&pdev->dev);
1382         pm_runtime_enable(&pdev->dev);
1383         pm_runtime_get_sync(&pdev->dev);
1384
1385         ui[pdev->id] = up;
1386         serial_omap_add_console_port(up);
1387
1388         ret = uart_add_one_port(&serial_omap_reg, &up->port);
1389         if (ret != 0)
1390                 goto do_release_region;
1391
1392         pm_runtime_put(&pdev->dev);
1393         platform_set_drvdata(pdev, up);
1394         return 0;
1395 err:
1396         dev_err(&pdev->dev, "[UART%d]: failure [%s]: %d\n",
1397                                 pdev->id, __func__, ret);
1398 do_release_region:
1399         release_mem_region(mem->start, resource_size(mem));
1400         return ret;
1401 }
1402
1403 static int serial_omap_remove(struct platform_device *dev)
1404 {
1405         struct uart_omap_port *up = platform_get_drvdata(dev);
1406
1407         if (up) {
1408                 pm_runtime_disable(&up->pdev->dev);
1409                 uart_remove_one_port(&serial_omap_reg, &up->port);
1410                 kfree(up);
1411         }
1412
1413         platform_set_drvdata(dev, NULL);
1414         return 0;
1415 }
1416
1417 static void serial_omap_restore_context(struct uart_omap_port *up)
1418 {
1419         serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1420         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1421         serial_out(up, UART_EFR, UART_EFR_ECB);
1422         serial_out(up, UART_LCR, 0x0); /* Operational mode */
1423         serial_out(up, UART_IER, 0x0);
1424         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1425         serial_out(up, UART_DLL, up->dll);
1426         serial_out(up, UART_DLM, up->dlh);
1427         serial_out(up, UART_LCR, 0x0); /* Operational mode */
1428         serial_out(up, UART_IER, up->ier);
1429         serial_out(up, UART_FCR, up->fcr);
1430         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1431         serial_out(up, UART_MCR, up->mcr);
1432         serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1433         serial_out(up, UART_OMAP_SCR, up->scr);
1434         serial_out(up, UART_EFR, up->efr);
1435         serial_out(up, UART_LCR, up->lcr);
1436         serial_out(up, UART_OMAP_MDR1, up->mdr1);
1437 }
1438
1439 #ifdef CONFIG_PM_RUNTIME
1440 static int serial_omap_runtime_suspend(struct device *dev)
1441 {
1442         return 0;
1443 }
1444
1445 static int serial_omap_runtime_resume(struct device *dev)
1446 {
1447         struct uart_omap_port *up = dev_get_drvdata(dev);
1448
1449         if (up)
1450                 serial_omap_restore_context(up);
1451
1452         return 0;
1453 }
1454 #endif
1455
1456 static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1457         SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1458         SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1459                                 serial_omap_runtime_resume, NULL)
1460 };
1461
1462 static struct platform_driver serial_omap_driver = {
1463         .probe          = serial_omap_probe,
1464         .remove         = serial_omap_remove,
1465         .driver         = {
1466                 .name   = DRIVER_NAME,
1467                 .pm     = &serial_omap_dev_pm_ops,
1468         },
1469 };
1470
1471 static int __init serial_omap_init(void)
1472 {
1473         int ret;
1474
1475         ret = uart_register_driver(&serial_omap_reg);
1476         if (ret != 0)
1477                 return ret;
1478         ret = platform_driver_register(&serial_omap_driver);
1479         if (ret != 0)
1480                 uart_unregister_driver(&serial_omap_reg);
1481         return ret;
1482 }
1483
1484 static void __exit serial_omap_exit(void)
1485 {
1486         platform_driver_unregister(&serial_omap_driver);
1487         uart_unregister_driver(&serial_omap_reg);
1488 }
1489
1490 module_init(serial_omap_init);
1491 module_exit(serial_omap_exit);
1492
1493 MODULE_DESCRIPTION("OMAP High Speed UART driver");
1494 MODULE_LICENSE("GPL");
1495 MODULE_AUTHOR("Texas Instruments Inc");