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1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Driver for OMAP-UART controller.
4 * Based on drivers/serial/8250.c
5 *
6 * Copyright (C) 2010 Texas Instruments.
7 *
8 * Authors:
9 * Govindraj R <govindraj.raja@ti.com>
10 * Thara Gopinath <thara@ti.com>
11 *
12 * Note: This driver is made separate from 8250 driver as we cannot
13 * over load 8250 driver with omap platform specific configuration for
14 * features like DMA, it makes easier to implement features like DMA and
15 * hardware flow control and software flow control configuration with
16 * this driver as required for the omap-platform.
17 */
18
19#include <linux/module.h>
20#include <linux/init.h>
21#include <linux/console.h>
22#include <linux/serial.h>
23#include <linux/serial_reg.h>
24#include <linux/delay.h>
25#include <linux/slab.h>
26#include <linux/tty.h>
27#include <linux/tty_flip.h>
28#include <linux/platform_device.h>
29#include <linux/io.h>
30#include <linux/clk.h>
31#include <linux/serial_core.h>
32#include <linux/irq.h>
33#include <linux/pm_runtime.h>
34#include <linux/pm_wakeirq.h>
35#include <linux/of.h>
36#include <linux/of_irq.h>
37#include <linux/gpio/consumer.h>
38#include <linux/platform_data/serial-omap.h>
39
40#define OMAP_MAX_HSUART_PORTS 10
41
42#define UART_BUILD_REVISION(x, y) (((x) << 8) | (y))
43
44#define OMAP_UART_REV_42 0x0402
45#define OMAP_UART_REV_46 0x0406
46#define OMAP_UART_REV_52 0x0502
47#define OMAP_UART_REV_63 0x0603
48
49#define OMAP_UART_TX_WAKEUP_EN BIT(7)
50
51/* Feature flags */
52#define OMAP_UART_WER_HAS_TX_WAKEUP BIT(0)
53
54#define UART_ERRATA_i202_MDR1_ACCESS BIT(0)
55#define UART_ERRATA_i291_DMA_FORCEIDLE BIT(1)
56
57#define DEFAULT_CLK_SPEED 48000000 /* 48Mhz */
58
59/* SCR register bitmasks */
60#define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK (1 << 7)
61#define OMAP_UART_SCR_TX_TRIG_GRANU1_MASK (1 << 6)
62#define OMAP_UART_SCR_TX_EMPTY (1 << 3)
63
64/* FCR register bitmasks */
65#define OMAP_UART_FCR_RX_FIFO_TRIG_MASK (0x3 << 6)
66#define OMAP_UART_FCR_TX_FIFO_TRIG_MASK (0x3 << 4)
67
68/* MVR register bitmasks */
69#define OMAP_UART_MVR_SCHEME_SHIFT 30
70
71#define OMAP_UART_LEGACY_MVR_MAJ_MASK 0xf0
72#define OMAP_UART_LEGACY_MVR_MAJ_SHIFT 4
73#define OMAP_UART_LEGACY_MVR_MIN_MASK 0x0f
74
75#define OMAP_UART_MVR_MAJ_MASK 0x700
76#define OMAP_UART_MVR_MAJ_SHIFT 8
77#define OMAP_UART_MVR_MIN_MASK 0x3f
78
79#define OMAP_UART_DMA_CH_FREE -1
80
81#define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
82#define OMAP_MODE13X_SPEED 230400
83
84/* WER = 0x7F
85 * Enable module level wakeup in WER reg
86 */
87#define OMAP_UART_WER_MOD_WKUP 0x7F
88
89/* Enable XON/XOFF flow control on output */
90#define OMAP_UART_SW_TX 0x08
91
92/* Enable XON/XOFF flow control on input */
93#define OMAP_UART_SW_RX 0x02
94
95#define OMAP_UART_SW_CLR 0xF0
96
97#define OMAP_UART_TCR_TRIG 0x0F
98
99struct uart_omap_dma {
100 u8 uart_dma_tx;
101 u8 uart_dma_rx;
102 int rx_dma_channel;
103 int tx_dma_channel;
104 dma_addr_t rx_buf_dma_phys;
105 dma_addr_t tx_buf_dma_phys;
106 unsigned int uart_base;
107 /*
108 * Buffer for rx dma. It is not required for tx because the buffer
109 * comes from port structure.
110 */
111 unsigned char *rx_buf;
112 unsigned int prev_rx_dma_pos;
113 int tx_buf_size;
114 int tx_dma_used;
115 int rx_dma_used;
116 spinlock_t tx_lock;
117 spinlock_t rx_lock;
118 /* timer to poll activity on rx dma */
119 struct timer_list rx_timer;
120 unsigned int rx_buf_size;
121 unsigned int rx_poll_rate;
122 unsigned int rx_timeout;
123};
124
125struct uart_omap_port {
126 struct uart_port port;
127 struct uart_omap_dma uart_dma;
128 struct device *dev;
129 int wakeirq;
130
131 unsigned char ier;
132 unsigned char lcr;
133 unsigned char mcr;
134 unsigned char fcr;
135 unsigned char efr;
136 unsigned char dll;
137 unsigned char dlh;
138 unsigned char mdr1;
139 unsigned char scr;
140 unsigned char wer;
141
142 int use_dma;
143 /*
144 * Some bits in registers are cleared on a read, so they must
145 * be saved whenever the register is read, but the bits will not
146 * be immediately processed.
147 */
148 unsigned int lsr_break_flag;
149 unsigned char msr_saved_flags;
150 char name[20];
151 unsigned long port_activity;
152 int context_loss_cnt;
153 u32 errata;
154 u32 features;
155
156 struct gpio_desc *rts_gpiod;
157
158 struct pm_qos_request pm_qos_request;
159 u32 latency;
160 u32 calc_latency;
161 struct work_struct qos_work;
162 bool is_suspending;
163
164 unsigned int rs485_tx_filter_count;
165};
166
167#define to_uart_omap_port(p) ((container_of((p), struct uart_omap_port, port)))
168
169static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
170
171/* Forward declaration of functions */
172static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1);
173
174static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
175{
176 offset <<= up->port.regshift;
177 return readw(up->port.membase + offset);
178}
179
180static inline void serial_out(struct uart_omap_port *up, int offset, int value)
181{
182 offset <<= up->port.regshift;
183 writew(value, up->port.membase + offset);
184}
185
186static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
187{
188 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
189 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
190 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
191 serial_out(up, UART_FCR, 0);
192}
193
194#ifdef CONFIG_PM
195static int serial_omap_get_context_loss_count(struct uart_omap_port *up)
196{
197 struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
198
199 if (!pdata || !pdata->get_context_loss_count)
200 return -EINVAL;
201
202 return pdata->get_context_loss_count(up->dev);
203}
204
205/* REVISIT: Remove this when omap3 boots in device tree only mode */
206static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
207{
208 struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
209
210 if (!pdata || !pdata->enable_wakeup)
211 return;
212
213 pdata->enable_wakeup(up->dev, enable);
214}
215#endif /* CONFIG_PM */
216
217/*
218 * Calculate the absolute difference between the desired and actual baud
219 * rate for the given mode.
220 */
221static inline int calculate_baud_abs_diff(struct uart_port *port,
222 unsigned int baud, unsigned int mode)
223{
224 unsigned int n = port->uartclk / (mode * baud);
225 int abs_diff;
226
227 if (n == 0)
228 n = 1;
229
230 abs_diff = baud - (port->uartclk / (mode * n));
231 if (abs_diff < 0)
232 abs_diff = -abs_diff;
233
234 return abs_diff;
235}
236
237/*
238 * serial_omap_baud_is_mode16 - check if baud rate is MODE16X
239 * @port: uart port info
240 * @baud: baudrate for which mode needs to be determined
241 *
242 * Returns true if baud rate is MODE16X and false if MODE13X
243 * Original table in OMAP TRM named "UART Mode Baud Rates, Divisor Values,
244 * and Error Rates" determines modes not for all common baud rates.
245 * E.g. for 1000000 baud rate mode must be 16x, but according to that
246 * table it's determined as 13x.
247 */
248static bool
249serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
250{
251 int abs_diff_13 = calculate_baud_abs_diff(port, baud, 13);
252 int abs_diff_16 = calculate_baud_abs_diff(port, baud, 16);
253
254 return (abs_diff_13 >= abs_diff_16);
255}
256
257/*
258 * serial_omap_get_divisor - calculate divisor value
259 * @port: uart port info
260 * @baud: baudrate for which divisor needs to be calculated.
261 */
262static unsigned int
263serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
264{
265 unsigned int mode;
266
267 if (!serial_omap_baud_is_mode16(port, baud))
268 mode = 13;
269 else
270 mode = 16;
271 return port->uartclk/(mode * baud);
272}
273
274static void serial_omap_enable_ms(struct uart_port *port)
275{
276 struct uart_omap_port *up = to_uart_omap_port(port);
277
278 dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
279
280 up->ier |= UART_IER_MSI;
281 serial_out(up, UART_IER, up->ier);
282}
283
284static void serial_omap_stop_tx(struct uart_port *port)
285{
286 struct uart_omap_port *up = to_uart_omap_port(port);
287 int res;
288
289 /* Handle RS-485 */
290 if (port->rs485.flags & SER_RS485_ENABLED) {
291 if (up->scr & OMAP_UART_SCR_TX_EMPTY) {
292 /* THR interrupt is fired when both TX FIFO and TX
293 * shift register are empty. This means there's nothing
294 * left to transmit now, so make sure the THR interrupt
295 * is fired when TX FIFO is below the trigger level,
296 * disable THR interrupts and toggle the RS-485 GPIO
297 * data direction pin if needed.
298 */
299 up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
300 serial_out(up, UART_OMAP_SCR, up->scr);
301 res = (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) ?
302 1 : 0;
303 if (gpiod_get_value(up->rts_gpiod) != res) {
304 if (port->rs485.delay_rts_after_send > 0)
305 mdelay(
306 port->rs485.delay_rts_after_send);
307 gpiod_set_value(up->rts_gpiod, res);
308 }
309 } else {
310 /* We're asked to stop, but there's still stuff in the
311 * UART FIFO, so make sure the THR interrupt is fired
312 * when both TX FIFO and TX shift register are empty.
313 * The next THR interrupt (if no transmission is started
314 * in the meantime) will indicate the end of a
315 * transmission. Therefore we _don't_ disable THR
316 * interrupts in this situation.
317 */
318 up->scr |= OMAP_UART_SCR_TX_EMPTY;
319 serial_out(up, UART_OMAP_SCR, up->scr);
320 return;
321 }
322 }
323
324 if (up->ier & UART_IER_THRI) {
325 up->ier &= ~UART_IER_THRI;
326 serial_out(up, UART_IER, up->ier);
327 }
328}
329
330static void serial_omap_stop_rx(struct uart_port *port)
331{
332 struct uart_omap_port *up = to_uart_omap_port(port);
333
334 up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
335 up->port.read_status_mask &= ~UART_LSR_DR;
336 serial_out(up, UART_IER, up->ier);
337}
338
339static void serial_omap_put_char(struct uart_omap_port *up, unsigned char ch)
340{
341 serial_out(up, UART_TX, ch);
342
343 if ((up->port.rs485.flags & SER_RS485_ENABLED) &&
344 !(up->port.rs485.flags & SER_RS485_RX_DURING_TX))
345 up->rs485_tx_filter_count++;
346}
347
348static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
349{
350 u8 ch;
351
352 uart_port_tx_limited(&up->port, ch, up->port.fifosize / 4,
353 true,
354 serial_omap_put_char(up, ch),
355 ({}));
356}
357
358static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
359{
360 if (!(up->ier & UART_IER_THRI)) {
361 up->ier |= UART_IER_THRI;
362 serial_out(up, UART_IER, up->ier);
363 }
364}
365
366static void serial_omap_start_tx(struct uart_port *port)
367{
368 struct uart_omap_port *up = to_uart_omap_port(port);
369 int res;
370
371 /* Handle RS-485 */
372 if (port->rs485.flags & SER_RS485_ENABLED) {
373 /* Fire THR interrupts when FIFO is below trigger level */
374 up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
375 serial_out(up, UART_OMAP_SCR, up->scr);
376
377 /* if rts not already enabled */
378 res = (port->rs485.flags & SER_RS485_RTS_ON_SEND) ? 1 : 0;
379 if (gpiod_get_value(up->rts_gpiod) != res) {
380 gpiod_set_value(up->rts_gpiod, res);
381 if (port->rs485.delay_rts_before_send > 0)
382 mdelay(port->rs485.delay_rts_before_send);
383 }
384 }
385
386 if ((port->rs485.flags & SER_RS485_ENABLED) &&
387 !(port->rs485.flags & SER_RS485_RX_DURING_TX))
388 up->rs485_tx_filter_count = 0;
389
390 serial_omap_enable_ier_thri(up);
391}
392
393static void serial_omap_throttle(struct uart_port *port)
394{
395 struct uart_omap_port *up = to_uart_omap_port(port);
396 unsigned long flags;
397
398 spin_lock_irqsave(&up->port.lock, flags);
399 up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
400 serial_out(up, UART_IER, up->ier);
401 spin_unlock_irqrestore(&up->port.lock, flags);
402}
403
404static void serial_omap_unthrottle(struct uart_port *port)
405{
406 struct uart_omap_port *up = to_uart_omap_port(port);
407 unsigned long flags;
408
409 spin_lock_irqsave(&up->port.lock, flags);
410 up->ier |= UART_IER_RLSI | UART_IER_RDI;
411 serial_out(up, UART_IER, up->ier);
412 spin_unlock_irqrestore(&up->port.lock, flags);
413}
414
415static unsigned int check_modem_status(struct uart_omap_port *up)
416{
417 unsigned int status;
418
419 status = serial_in(up, UART_MSR);
420 status |= up->msr_saved_flags;
421 up->msr_saved_flags = 0;
422 if ((status & UART_MSR_ANY_DELTA) == 0)
423 return status;
424
425 if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
426 up->port.state != NULL) {
427 if (status & UART_MSR_TERI)
428 up->port.icount.rng++;
429 if (status & UART_MSR_DDSR)
430 up->port.icount.dsr++;
431 if (status & UART_MSR_DDCD)
432 uart_handle_dcd_change
433 (&up->port, status & UART_MSR_DCD);
434 if (status & UART_MSR_DCTS)
435 uart_handle_cts_change
436 (&up->port, status & UART_MSR_CTS);
437 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
438 }
439
440 return status;
441}
442
443static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
444{
445 unsigned int flag;
446
447 /*
448 * Read one data character out to avoid stalling the receiver according
449 * to the table 23-246 of the omap4 TRM.
450 */
451 if (likely(lsr & UART_LSR_DR)) {
452 serial_in(up, UART_RX);
453 if ((up->port.rs485.flags & SER_RS485_ENABLED) &&
454 !(up->port.rs485.flags & SER_RS485_RX_DURING_TX) &&
455 up->rs485_tx_filter_count)
456 up->rs485_tx_filter_count--;
457 }
458
459 up->port.icount.rx++;
460 flag = TTY_NORMAL;
461
462 if (lsr & UART_LSR_BI) {
463 flag = TTY_BREAK;
464 lsr &= ~(UART_LSR_FE | UART_LSR_PE);
465 up->port.icount.brk++;
466 /*
467 * We do the SysRQ and SAK checking
468 * here because otherwise the break
469 * may get masked by ignore_status_mask
470 * or read_status_mask.
471 */
472 if (uart_handle_break(&up->port))
473 return;
474
475 }
476
477 if (lsr & UART_LSR_PE) {
478 flag = TTY_PARITY;
479 up->port.icount.parity++;
480 }
481
482 if (lsr & UART_LSR_FE) {
483 flag = TTY_FRAME;
484 up->port.icount.frame++;
485 }
486
487 if (lsr & UART_LSR_OE)
488 up->port.icount.overrun++;
489
490#ifdef CONFIG_SERIAL_OMAP_CONSOLE
491 if (up->port.line == up->port.cons->index) {
492 /* Recover the break flag from console xmit */
493 lsr |= up->lsr_break_flag;
494 }
495#endif
496 uart_insert_char(&up->port, lsr, UART_LSR_OE, 0, flag);
497}
498
499static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr)
500{
501 unsigned char ch = 0;
502 unsigned int flag;
503
504 if (!(lsr & UART_LSR_DR))
505 return;
506
507 ch = serial_in(up, UART_RX);
508 if ((up->port.rs485.flags & SER_RS485_ENABLED) &&
509 !(up->port.rs485.flags & SER_RS485_RX_DURING_TX) &&
510 up->rs485_tx_filter_count) {
511 up->rs485_tx_filter_count--;
512 return;
513 }
514
515 flag = TTY_NORMAL;
516 up->port.icount.rx++;
517
518 if (uart_handle_sysrq_char(&up->port, ch))
519 return;
520
521 uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
522}
523
524/**
525 * serial_omap_irq() - This handles the interrupt from one port
526 * @irq: uart port irq number
527 * @dev_id: uart port info
528 */
529static irqreturn_t serial_omap_irq(int irq, void *dev_id)
530{
531 struct uart_omap_port *up = dev_id;
532 unsigned int iir, lsr;
533 unsigned int type;
534 irqreturn_t ret = IRQ_NONE;
535 int max_count = 256;
536
537 spin_lock(&up->port.lock);
538
539 do {
540 iir = serial_in(up, UART_IIR);
541 if (iir & UART_IIR_NO_INT)
542 break;
543
544 ret = IRQ_HANDLED;
545 lsr = serial_in(up, UART_LSR);
546
547 /* extract IRQ type from IIR register */
548 type = iir & 0x3e;
549
550 switch (type) {
551 case UART_IIR_MSI:
552 check_modem_status(up);
553 break;
554 case UART_IIR_THRI:
555 transmit_chars(up, lsr);
556 break;
557 case UART_IIR_RX_TIMEOUT:
558 case UART_IIR_RDI:
559 serial_omap_rdi(up, lsr);
560 break;
561 case UART_IIR_RLSI:
562 serial_omap_rlsi(up, lsr);
563 break;
564 case UART_IIR_CTS_RTS_DSR:
565 /* simply try again */
566 break;
567 case UART_IIR_XOFF:
568 default:
569 break;
570 }
571 } while (max_count--);
572
573 spin_unlock(&up->port.lock);
574
575 tty_flip_buffer_push(&up->port.state->port);
576
577 up->port_activity = jiffies;
578
579 return ret;
580}
581
582static unsigned int serial_omap_tx_empty(struct uart_port *port)
583{
584 struct uart_omap_port *up = to_uart_omap_port(port);
585 unsigned long flags;
586 unsigned int ret = 0;
587
588 dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line);
589 spin_lock_irqsave(&up->port.lock, flags);
590 ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
591 spin_unlock_irqrestore(&up->port.lock, flags);
592
593 return ret;
594}
595
596static unsigned int serial_omap_get_mctrl(struct uart_port *port)
597{
598 struct uart_omap_port *up = to_uart_omap_port(port);
599 unsigned int status;
600 unsigned int ret = 0;
601
602 status = check_modem_status(up);
603
604 dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line);
605
606 if (status & UART_MSR_DCD)
607 ret |= TIOCM_CAR;
608 if (status & UART_MSR_RI)
609 ret |= TIOCM_RNG;
610 if (status & UART_MSR_DSR)
611 ret |= TIOCM_DSR;
612 if (status & UART_MSR_CTS)
613 ret |= TIOCM_CTS;
614 return ret;
615}
616
617static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
618{
619 struct uart_omap_port *up = to_uart_omap_port(port);
620 unsigned char mcr = 0, old_mcr, lcr;
621
622 dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
623 if (mctrl & TIOCM_RTS)
624 mcr |= UART_MCR_RTS;
625 if (mctrl & TIOCM_DTR)
626 mcr |= UART_MCR_DTR;
627 if (mctrl & TIOCM_OUT1)
628 mcr |= UART_MCR_OUT1;
629 if (mctrl & TIOCM_OUT2)
630 mcr |= UART_MCR_OUT2;
631 if (mctrl & TIOCM_LOOP)
632 mcr |= UART_MCR_LOOP;
633
634 old_mcr = serial_in(up, UART_MCR);
635 old_mcr &= ~(UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_OUT1 |
636 UART_MCR_DTR | UART_MCR_RTS);
637 up->mcr = old_mcr | mcr;
638 serial_out(up, UART_MCR, up->mcr);
639
640 /* Turn off autoRTS if RTS is lowered; restore autoRTS if RTS raised */
641 lcr = serial_in(up, UART_LCR);
642 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
643 if ((mctrl & TIOCM_RTS) && (port->status & UPSTAT_AUTORTS))
644 up->efr |= UART_EFR_RTS;
645 else
646 up->efr &= ~UART_EFR_RTS;
647 serial_out(up, UART_EFR, up->efr);
648 serial_out(up, UART_LCR, lcr);
649}
650
651static void serial_omap_break_ctl(struct uart_port *port, int break_state)
652{
653 struct uart_omap_port *up = to_uart_omap_port(port);
654 unsigned long flags;
655
656 dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
657 spin_lock_irqsave(&up->port.lock, flags);
658 if (break_state == -1)
659 up->lcr |= UART_LCR_SBC;
660 else
661 up->lcr &= ~UART_LCR_SBC;
662 serial_out(up, UART_LCR, up->lcr);
663 spin_unlock_irqrestore(&up->port.lock, flags);
664}
665
666static int serial_omap_startup(struct uart_port *port)
667{
668 struct uart_omap_port *up = to_uart_omap_port(port);
669 unsigned long flags;
670 int retval;
671
672 /*
673 * Allocate the IRQ
674 */
675 retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
676 up->name, up);
677 if (retval)
678 return retval;
679
680 /* Optional wake-up IRQ */
681 if (up->wakeirq) {
682 retval = dev_pm_set_dedicated_wake_irq(up->dev, up->wakeirq);
683 if (retval) {
684 free_irq(up->port.irq, up);
685 return retval;
686 }
687 }
688
689 dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
690
691 pm_runtime_get_sync(up->dev);
692 /*
693 * Clear the FIFO buffers and disable them.
694 * (they will be reenabled in set_termios())
695 */
696 serial_omap_clear_fifos(up);
697
698 /*
699 * Clear the interrupt registers.
700 */
701 (void) serial_in(up, UART_LSR);
702 if (serial_in(up, UART_LSR) & UART_LSR_DR)
703 (void) serial_in(up, UART_RX);
704 (void) serial_in(up, UART_IIR);
705 (void) serial_in(up, UART_MSR);
706
707 /*
708 * Now, initialize the UART
709 */
710 serial_out(up, UART_LCR, UART_LCR_WLEN8);
711 spin_lock_irqsave(&up->port.lock, flags);
712 /*
713 * Most PC uarts need OUT2 raised to enable interrupts.
714 */
715 up->port.mctrl |= TIOCM_OUT2;
716 serial_omap_set_mctrl(&up->port, up->port.mctrl);
717 spin_unlock_irqrestore(&up->port.lock, flags);
718
719 up->msr_saved_flags = 0;
720 /*
721 * Finally, enable interrupts. Note: Modem status interrupts
722 * are set via set_termios(), which will be occurring imminently
723 * anyway, so we don't enable them here.
724 */
725 up->ier = UART_IER_RLSI | UART_IER_RDI;
726 serial_out(up, UART_IER, up->ier);
727
728 /* Enable module level wake up */
729 up->wer = OMAP_UART_WER_MOD_WKUP;
730 if (up->features & OMAP_UART_WER_HAS_TX_WAKEUP)
731 up->wer |= OMAP_UART_TX_WAKEUP_EN;
732
733 serial_out(up, UART_OMAP_WER, up->wer);
734
735 up->port_activity = jiffies;
736 return 0;
737}
738
739static void serial_omap_shutdown(struct uart_port *port)
740{
741 struct uart_omap_port *up = to_uart_omap_port(port);
742 unsigned long flags;
743
744 dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
745
746 /*
747 * Disable interrupts from this port
748 */
749 up->ier = 0;
750 serial_out(up, UART_IER, 0);
751
752 spin_lock_irqsave(&up->port.lock, flags);
753 up->port.mctrl &= ~TIOCM_OUT2;
754 serial_omap_set_mctrl(&up->port, up->port.mctrl);
755 spin_unlock_irqrestore(&up->port.lock, flags);
756
757 /*
758 * Disable break condition and FIFOs
759 */
760 serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
761 serial_omap_clear_fifos(up);
762
763 /*
764 * Read data port to reset things, and then free the irq
765 */
766 if (serial_in(up, UART_LSR) & UART_LSR_DR)
767 (void) serial_in(up, UART_RX);
768
769 pm_runtime_put_sync(up->dev);
770 free_irq(up->port.irq, up);
771 dev_pm_clear_wake_irq(up->dev);
772}
773
774static void serial_omap_uart_qos_work(struct work_struct *work)
775{
776 struct uart_omap_port *up = container_of(work, struct uart_omap_port,
777 qos_work);
778
779 cpu_latency_qos_update_request(&up->pm_qos_request, up->latency);
780}
781
782static void
783serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
784 const struct ktermios *old)
785{
786 struct uart_omap_port *up = to_uart_omap_port(port);
787 unsigned char cval = 0;
788 unsigned long flags;
789 unsigned int baud, quot;
790
791 cval = UART_LCR_WLEN(tty_get_char_size(termios->c_cflag));
792
793 if (termios->c_cflag & CSTOPB)
794 cval |= UART_LCR_STOP;
795 if (termios->c_cflag & PARENB)
796 cval |= UART_LCR_PARITY;
797 if (!(termios->c_cflag & PARODD))
798 cval |= UART_LCR_EPAR;
799 if (termios->c_cflag & CMSPAR)
800 cval |= UART_LCR_SPAR;
801
802 /*
803 * Ask the core to calculate the divisor for us.
804 */
805
806 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
807 quot = serial_omap_get_divisor(port, baud);
808
809 /* calculate wakeup latency constraint */
810 up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
811 up->latency = up->calc_latency;
812 schedule_work(&up->qos_work);
813
814 up->dll = quot & 0xff;
815 up->dlh = quot >> 8;
816 up->mdr1 = UART_OMAP_MDR1_DISABLE;
817
818 up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
819 UART_FCR_ENABLE_FIFO;
820
821 /*
822 * Ok, we're now changing the port state. Do it with
823 * interrupts disabled.
824 */
825 spin_lock_irqsave(&up->port.lock, flags);
826
827 /*
828 * Update the per-port timeout.
829 */
830 uart_update_timeout(port, termios->c_cflag, baud);
831
832 up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
833 if (termios->c_iflag & INPCK)
834 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
835 if (termios->c_iflag & (BRKINT | PARMRK))
836 up->port.read_status_mask |= UART_LSR_BI;
837
838 /*
839 * Characters to ignore
840 */
841 up->port.ignore_status_mask = 0;
842 if (termios->c_iflag & IGNPAR)
843 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
844 if (termios->c_iflag & IGNBRK) {
845 up->port.ignore_status_mask |= UART_LSR_BI;
846 /*
847 * If we're ignoring parity and break indicators,
848 * ignore overruns too (for real raw support).
849 */
850 if (termios->c_iflag & IGNPAR)
851 up->port.ignore_status_mask |= UART_LSR_OE;
852 }
853
854 /*
855 * ignore all characters if CREAD is not set
856 */
857 if ((termios->c_cflag & CREAD) == 0)
858 up->port.ignore_status_mask |= UART_LSR_DR;
859
860 /*
861 * Modem status interrupts
862 */
863 up->ier &= ~UART_IER_MSI;
864 if (UART_ENABLE_MS(&up->port, termios->c_cflag))
865 up->ier |= UART_IER_MSI;
866 serial_out(up, UART_IER, up->ier);
867 serial_out(up, UART_LCR, cval); /* reset DLAB */
868 up->lcr = cval;
869 up->scr = 0;
870
871 /* FIFOs and DMA Settings */
872
873 /* FCR can be changed only when the
874 * baud clock is not running
875 * DLL_REG and DLH_REG set to 0.
876 */
877 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
878 serial_out(up, UART_DLL, 0);
879 serial_out(up, UART_DLM, 0);
880 serial_out(up, UART_LCR, 0);
881
882 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
883
884 up->efr = serial_in(up, UART_EFR) & ~UART_EFR_ECB;
885 up->efr &= ~UART_EFR_SCD;
886 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
887
888 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
889 up->mcr = serial_in(up, UART_MCR) & ~UART_MCR_TCRTLR;
890 serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
891 /* FIFO ENABLE, DMA MODE */
892
893 up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
894 /*
895 * NOTE: Setting OMAP_UART_SCR_RX_TRIG_GRANU1_MASK
896 * sets Enables the granularity of 1 for TRIGGER RX
897 * level. Along with setting RX FIFO trigger level
898 * to 1 (as noted below, 16 characters) and TLR[3:0]
899 * to zero this will result RX FIFO threshold level
900 * to 1 character, instead of 16 as noted in comment
901 * below.
902 */
903
904 /* Set receive FIFO threshold to 16 characters and
905 * transmit FIFO threshold to 32 spaces
906 */
907 up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
908 up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK;
909 up->fcr |= UART_FCR6_R_TRIGGER_16 | UART_FCR6_T_TRIGGER_24 |
910 UART_FCR_ENABLE_FIFO;
911
912 serial_out(up, UART_FCR, up->fcr);
913 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
914
915 serial_out(up, UART_OMAP_SCR, up->scr);
916
917 /* Reset UART_MCR_TCRTLR: this must be done with the EFR_ECB bit set */
918 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
919 serial_out(up, UART_MCR, up->mcr);
920 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
921 serial_out(up, UART_EFR, up->efr);
922 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
923
924 /* Protocol, Baud Rate, and Interrupt Settings */
925
926 if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
927 serial_omap_mdr1_errataset(up, up->mdr1);
928 else
929 serial_out(up, UART_OMAP_MDR1, up->mdr1);
930
931 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
932 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
933
934 serial_out(up, UART_LCR, 0);
935 serial_out(up, UART_IER, 0);
936 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
937
938 serial_out(up, UART_DLL, up->dll); /* LS of divisor */
939 serial_out(up, UART_DLM, up->dlh); /* MS of divisor */
940
941 serial_out(up, UART_LCR, 0);
942 serial_out(up, UART_IER, up->ier);
943 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
944
945 serial_out(up, UART_EFR, up->efr);
946 serial_out(up, UART_LCR, cval);
947
948 if (!serial_omap_baud_is_mode16(port, baud))
949 up->mdr1 = UART_OMAP_MDR1_13X_MODE;
950 else
951 up->mdr1 = UART_OMAP_MDR1_16X_MODE;
952
953 if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
954 serial_omap_mdr1_errataset(up, up->mdr1);
955 else
956 serial_out(up, UART_OMAP_MDR1, up->mdr1);
957
958 /* Configure flow control */
959 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
960
961 /* XON1/XOFF1 accessible mode B, TCRTLR=0, ECB=0 */
962 serial_out(up, UART_XON1, termios->c_cc[VSTART]);
963 serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
964
965 /* Enable access to TCR/TLR */
966 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
967 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
968 serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
969
970 serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
971
972 up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF);
973
974 if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
975 /* Enable AUTOCTS (autoRTS is enabled when RTS is raised) */
976 up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS;
977 up->efr |= UART_EFR_CTS;
978 } else {
979 /* Disable AUTORTS and AUTOCTS */
980 up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS);
981 }
982
983 if (up->port.flags & UPF_SOFT_FLOW) {
984 /* clear SW control mode bits */
985 up->efr &= OMAP_UART_SW_CLR;
986
987 /*
988 * IXON Flag:
989 * Enable XON/XOFF flow control on input.
990 * Receiver compares XON1, XOFF1.
991 */
992 if (termios->c_iflag & IXON)
993 up->efr |= OMAP_UART_SW_RX;
994
995 /*
996 * IXOFF Flag:
997 * Enable XON/XOFF flow control on output.
998 * Transmit XON1, XOFF1
999 */
1000 if (termios->c_iflag & IXOFF) {
1001 up->port.status |= UPSTAT_AUTOXOFF;
1002 up->efr |= OMAP_UART_SW_TX;
1003 }
1004
1005 /*
1006 * IXANY Flag:
1007 * Enable any character to restart output.
1008 * Operation resumes after receiving any
1009 * character after recognition of the XOFF character
1010 */
1011 if (termios->c_iflag & IXANY)
1012 up->mcr |= UART_MCR_XONANY;
1013 else
1014 up->mcr &= ~UART_MCR_XONANY;
1015 }
1016 serial_out(up, UART_MCR, up->mcr);
1017 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1018 serial_out(up, UART_EFR, up->efr);
1019 serial_out(up, UART_LCR, up->lcr);
1020
1021 serial_omap_set_mctrl(&up->port, up->port.mctrl);
1022
1023 spin_unlock_irqrestore(&up->port.lock, flags);
1024 dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
1025}
1026
1027static void
1028serial_omap_pm(struct uart_port *port, unsigned int state,
1029 unsigned int oldstate)
1030{
1031 struct uart_omap_port *up = to_uart_omap_port(port);
1032 unsigned char efr;
1033
1034 dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line);
1035
1036 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1037 efr = serial_in(up, UART_EFR);
1038 serial_out(up, UART_EFR, efr | UART_EFR_ECB);
1039 serial_out(up, UART_LCR, 0);
1040
1041 serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
1042 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1043 serial_out(up, UART_EFR, efr);
1044 serial_out(up, UART_LCR, 0);
1045}
1046
1047static void serial_omap_release_port(struct uart_port *port)
1048{
1049 dev_dbg(port->dev, "serial_omap_release_port+\n");
1050}
1051
1052static int serial_omap_request_port(struct uart_port *port)
1053{
1054 dev_dbg(port->dev, "serial_omap_request_port+\n");
1055 return 0;
1056}
1057
1058static void serial_omap_config_port(struct uart_port *port, int flags)
1059{
1060 struct uart_omap_port *up = to_uart_omap_port(port);
1061
1062 dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
1063 up->port.line);
1064 up->port.type = PORT_OMAP;
1065 up->port.flags |= UPF_SOFT_FLOW | UPF_HARD_FLOW;
1066}
1067
1068static int
1069serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
1070{
1071 /* we don't want the core code to modify any port params */
1072 dev_dbg(port->dev, "serial_omap_verify_port+\n");
1073 return -EINVAL;
1074}
1075
1076static const char *
1077serial_omap_type(struct uart_port *port)
1078{
1079 struct uart_omap_port *up = to_uart_omap_port(port);
1080
1081 dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
1082 return up->name;
1083}
1084
1085static void __maybe_unused wait_for_xmitr(struct uart_omap_port *up)
1086{
1087 unsigned int status, tmout = 10000;
1088
1089 /* Wait up to 10ms for the character(s) to be sent. */
1090 do {
1091 status = serial_in(up, UART_LSR);
1092
1093 if (status & UART_LSR_BI)
1094 up->lsr_break_flag = UART_LSR_BI;
1095
1096 if (--tmout == 0)
1097 break;
1098 udelay(1);
1099 } while (!uart_lsr_tx_empty(status));
1100
1101 /* Wait up to 1s for flow control if necessary */
1102 if (up->port.flags & UPF_CONS_FLOW) {
1103 tmout = 1000000;
1104 for (tmout = 1000000; tmout; tmout--) {
1105 unsigned int msr = serial_in(up, UART_MSR);
1106
1107 up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
1108 if (msr & UART_MSR_CTS)
1109 break;
1110
1111 udelay(1);
1112 }
1113 }
1114}
1115
1116#ifdef CONFIG_CONSOLE_POLL
1117
1118static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
1119{
1120 struct uart_omap_port *up = to_uart_omap_port(port);
1121
1122 wait_for_xmitr(up);
1123 serial_out(up, UART_TX, ch);
1124}
1125
1126static int serial_omap_poll_get_char(struct uart_port *port)
1127{
1128 struct uart_omap_port *up = to_uart_omap_port(port);
1129 unsigned int status;
1130
1131 status = serial_in(up, UART_LSR);
1132 if (!(status & UART_LSR_DR)) {
1133 status = NO_POLL_CHAR;
1134 goto out;
1135 }
1136
1137 status = serial_in(up, UART_RX);
1138
1139out:
1140 return status;
1141}
1142
1143#endif /* CONFIG_CONSOLE_POLL */
1144
1145#ifdef CONFIG_SERIAL_OMAP_CONSOLE
1146
1147#ifdef CONFIG_SERIAL_EARLYCON
1148static unsigned int omap_serial_early_in(struct uart_port *port, int offset)
1149{
1150 offset <<= port->regshift;
1151 return readw(port->membase + offset);
1152}
1153
1154static void omap_serial_early_out(struct uart_port *port, int offset,
1155 int value)
1156{
1157 offset <<= port->regshift;
1158 writew(value, port->membase + offset);
1159}
1160
1161static void omap_serial_early_putc(struct uart_port *port, unsigned char c)
1162{
1163 unsigned int status;
1164
1165 for (;;) {
1166 status = omap_serial_early_in(port, UART_LSR);
1167 if (uart_lsr_tx_empty(status))
1168 break;
1169 cpu_relax();
1170 }
1171 omap_serial_early_out(port, UART_TX, c);
1172}
1173
1174static void early_omap_serial_write(struct console *console, const char *s,
1175 unsigned int count)
1176{
1177 struct earlycon_device *device = console->data;
1178 struct uart_port *port = &device->port;
1179
1180 uart_console_write(port, s, count, omap_serial_early_putc);
1181}
1182
1183static int __init early_omap_serial_setup(struct earlycon_device *device,
1184 const char *options)
1185{
1186 struct uart_port *port = &device->port;
1187
1188 if (!(device->port.membase || device->port.iobase))
1189 return -ENODEV;
1190
1191 port->regshift = 2;
1192 device->con->write = early_omap_serial_write;
1193 return 0;
1194}
1195
1196OF_EARLYCON_DECLARE(omapserial, "ti,omap2-uart", early_omap_serial_setup);
1197OF_EARLYCON_DECLARE(omapserial, "ti,omap3-uart", early_omap_serial_setup);
1198OF_EARLYCON_DECLARE(omapserial, "ti,omap4-uart", early_omap_serial_setup);
1199#endif /* CONFIG_SERIAL_EARLYCON */
1200
1201static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS];
1202
1203static struct uart_driver serial_omap_reg;
1204
1205static void serial_omap_console_putchar(struct uart_port *port, unsigned char ch)
1206{
1207 struct uart_omap_port *up = to_uart_omap_port(port);
1208
1209 wait_for_xmitr(up);
1210 serial_out(up, UART_TX, ch);
1211}
1212
1213static void
1214serial_omap_console_write(struct console *co, const char *s,
1215 unsigned int count)
1216{
1217 struct uart_omap_port *up = serial_omap_console_ports[co->index];
1218 unsigned long flags;
1219 unsigned int ier;
1220 int locked = 1;
1221
1222 local_irq_save(flags);
1223 if (up->port.sysrq)
1224 locked = 0;
1225 else if (oops_in_progress)
1226 locked = spin_trylock(&up->port.lock);
1227 else
1228 spin_lock(&up->port.lock);
1229
1230 /*
1231 * First save the IER then disable the interrupts
1232 */
1233 ier = serial_in(up, UART_IER);
1234 serial_out(up, UART_IER, 0);
1235
1236 uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1237
1238 /*
1239 * Finally, wait for transmitter to become empty
1240 * and restore the IER
1241 */
1242 wait_for_xmitr(up);
1243 serial_out(up, UART_IER, ier);
1244 /*
1245 * The receive handling will happen properly because the
1246 * receive ready bit will still be set; it is not cleared
1247 * on read. However, modem control will not, we must
1248 * call it if we have saved something in the saved flags
1249 * while processing with interrupts off.
1250 */
1251 if (up->msr_saved_flags)
1252 check_modem_status(up);
1253
1254 if (locked)
1255 spin_unlock(&up->port.lock);
1256 local_irq_restore(flags);
1257}
1258
1259static int __init
1260serial_omap_console_setup(struct console *co, char *options)
1261{
1262 struct uart_omap_port *up;
1263 int baud = 115200;
1264 int bits = 8;
1265 int parity = 'n';
1266 int flow = 'n';
1267
1268 if (serial_omap_console_ports[co->index] == NULL)
1269 return -ENODEV;
1270 up = serial_omap_console_ports[co->index];
1271
1272 if (options)
1273 uart_parse_options(options, &baud, &parity, &bits, &flow);
1274
1275 return uart_set_options(&up->port, co, baud, parity, bits, flow);
1276}
1277
1278static struct console serial_omap_console = {
1279 .name = OMAP_SERIAL_NAME,
1280 .write = serial_omap_console_write,
1281 .device = uart_console_device,
1282 .setup = serial_omap_console_setup,
1283 .flags = CON_PRINTBUFFER,
1284 .index = -1,
1285 .data = &serial_omap_reg,
1286};
1287
1288static void serial_omap_add_console_port(struct uart_omap_port *up)
1289{
1290 serial_omap_console_ports[up->port.line] = up;
1291}
1292
1293#define OMAP_CONSOLE (&serial_omap_console)
1294
1295#else
1296
1297#define OMAP_CONSOLE NULL
1298
1299static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1300{}
1301
1302#endif
1303
1304/* Enable or disable the rs485 support */
1305static int
1306serial_omap_config_rs485(struct uart_port *port, struct ktermios *termios,
1307 struct serial_rs485 *rs485)
1308{
1309 struct uart_omap_port *up = to_uart_omap_port(port);
1310 unsigned int mode;
1311 int val;
1312
1313 /* Disable interrupts from this port */
1314 mode = up->ier;
1315 up->ier = 0;
1316 serial_out(up, UART_IER, 0);
1317
1318 /* enable / disable rts */
1319 val = (rs485->flags & SER_RS485_ENABLED) ?
1320 SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND;
1321 val = (rs485->flags & val) ? 1 : 0;
1322 gpiod_set_value(up->rts_gpiod, val);
1323
1324 /* Enable interrupts */
1325 up->ier = mode;
1326 serial_out(up, UART_IER, up->ier);
1327
1328 /* If RS-485 is disabled, make sure the THR interrupt is fired when
1329 * TX FIFO is below the trigger level.
1330 */
1331 if (!(rs485->flags & SER_RS485_ENABLED) &&
1332 (up->scr & OMAP_UART_SCR_TX_EMPTY)) {
1333 up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
1334 serial_out(up, UART_OMAP_SCR, up->scr);
1335 }
1336
1337 return 0;
1338}
1339
1340static const struct uart_ops serial_omap_pops = {
1341 .tx_empty = serial_omap_tx_empty,
1342 .set_mctrl = serial_omap_set_mctrl,
1343 .get_mctrl = serial_omap_get_mctrl,
1344 .stop_tx = serial_omap_stop_tx,
1345 .start_tx = serial_omap_start_tx,
1346 .throttle = serial_omap_throttle,
1347 .unthrottle = serial_omap_unthrottle,
1348 .stop_rx = serial_omap_stop_rx,
1349 .enable_ms = serial_omap_enable_ms,
1350 .break_ctl = serial_omap_break_ctl,
1351 .startup = serial_omap_startup,
1352 .shutdown = serial_omap_shutdown,
1353 .set_termios = serial_omap_set_termios,
1354 .pm = serial_omap_pm,
1355 .type = serial_omap_type,
1356 .release_port = serial_omap_release_port,
1357 .request_port = serial_omap_request_port,
1358 .config_port = serial_omap_config_port,
1359 .verify_port = serial_omap_verify_port,
1360#ifdef CONFIG_CONSOLE_POLL
1361 .poll_put_char = serial_omap_poll_put_char,
1362 .poll_get_char = serial_omap_poll_get_char,
1363#endif
1364};
1365
1366static struct uart_driver serial_omap_reg = {
1367 .owner = THIS_MODULE,
1368 .driver_name = "OMAP-SERIAL",
1369 .dev_name = OMAP_SERIAL_NAME,
1370 .nr = OMAP_MAX_HSUART_PORTS,
1371 .cons = OMAP_CONSOLE,
1372};
1373
1374#ifdef CONFIG_PM_SLEEP
1375static int serial_omap_prepare(struct device *dev)
1376{
1377 struct uart_omap_port *up = dev_get_drvdata(dev);
1378
1379 up->is_suspending = true;
1380
1381 return 0;
1382}
1383
1384static void serial_omap_complete(struct device *dev)
1385{
1386 struct uart_omap_port *up = dev_get_drvdata(dev);
1387
1388 up->is_suspending = false;
1389}
1390
1391static int serial_omap_suspend(struct device *dev)
1392{
1393 struct uart_omap_port *up = dev_get_drvdata(dev);
1394
1395 uart_suspend_port(&serial_omap_reg, &up->port);
1396 flush_work(&up->qos_work);
1397
1398 if (device_may_wakeup(dev))
1399 serial_omap_enable_wakeup(up, true);
1400 else
1401 serial_omap_enable_wakeup(up, false);
1402
1403 return 0;
1404}
1405
1406static int serial_omap_resume(struct device *dev)
1407{
1408 struct uart_omap_port *up = dev_get_drvdata(dev);
1409
1410 if (device_may_wakeup(dev))
1411 serial_omap_enable_wakeup(up, false);
1412
1413 uart_resume_port(&serial_omap_reg, &up->port);
1414
1415 return 0;
1416}
1417#else
1418#define serial_omap_prepare NULL
1419#define serial_omap_complete NULL
1420#endif /* CONFIG_PM_SLEEP */
1421
1422static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
1423{
1424 u32 mvr, scheme;
1425 u16 revision, major, minor;
1426
1427 mvr = readl(up->port.membase + (UART_OMAP_MVER << up->port.regshift));
1428
1429 /* Check revision register scheme */
1430 scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
1431
1432 switch (scheme) {
1433 case 0: /* Legacy Scheme: OMAP2/3 */
1434 /* MINOR_REV[0:4], MAJOR_REV[4:7] */
1435 major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
1436 OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
1437 minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
1438 break;
1439 case 1:
1440 /* New Scheme: OMAP4+ */
1441 /* MINOR_REV[0:5], MAJOR_REV[8:10] */
1442 major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
1443 OMAP_UART_MVR_MAJ_SHIFT;
1444 minor = (mvr & OMAP_UART_MVR_MIN_MASK);
1445 break;
1446 default:
1447 dev_warn(up->dev,
1448 "Unknown %s revision, defaulting to highest\n",
1449 up->name);
1450 /* highest possible revision */
1451 major = 0xff;
1452 minor = 0xff;
1453 }
1454
1455 /* normalize revision for the driver */
1456 revision = UART_BUILD_REVISION(major, minor);
1457
1458 switch (revision) {
1459 case OMAP_UART_REV_46:
1460 up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1461 UART_ERRATA_i291_DMA_FORCEIDLE);
1462 break;
1463 case OMAP_UART_REV_52:
1464 up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1465 UART_ERRATA_i291_DMA_FORCEIDLE);
1466 up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1467 break;
1468 case OMAP_UART_REV_63:
1469 up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
1470 up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1471 break;
1472 default:
1473 break;
1474 }
1475}
1476
1477static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
1478{
1479 struct omap_uart_port_info *omap_up_info;
1480
1481 omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
1482 if (!omap_up_info)
1483 return NULL; /* out of memory */
1484
1485 of_property_read_u32(dev->of_node, "clock-frequency",
1486 &omap_up_info->uartclk);
1487
1488 omap_up_info->flags = UPF_BOOT_AUTOCONF;
1489
1490 return omap_up_info;
1491}
1492
1493static int serial_omap_probe_rs485(struct uart_omap_port *up,
1494 struct device *dev)
1495{
1496 struct serial_rs485 *rs485conf = &up->port.rs485;
1497 struct device_node *np = dev->of_node;
1498 enum gpiod_flags gflags;
1499 int ret;
1500
1501 rs485conf->flags = 0;
1502 up->rts_gpiod = NULL;
1503
1504 if (!np)
1505 return 0;
1506
1507 ret = uart_get_rs485_mode(&up->port);
1508 if (ret)
1509 return ret;
1510
1511 if (of_property_read_bool(np, "rs485-rts-active-high")) {
1512 rs485conf->flags |= SER_RS485_RTS_ON_SEND;
1513 rs485conf->flags &= ~SER_RS485_RTS_AFTER_SEND;
1514 } else {
1515 rs485conf->flags &= ~SER_RS485_RTS_ON_SEND;
1516 rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
1517 }
1518
1519 /* check for tx enable gpio */
1520 gflags = rs485conf->flags & SER_RS485_RTS_AFTER_SEND ?
1521 GPIOD_OUT_HIGH : GPIOD_OUT_LOW;
1522 up->rts_gpiod = devm_gpiod_get_optional(dev, "rts", gflags);
1523 if (IS_ERR(up->rts_gpiod)) {
1524 ret = PTR_ERR(up->rts_gpiod);
1525 if (ret == -EPROBE_DEFER)
1526 return ret;
1527
1528 up->rts_gpiod = NULL;
1529 up->port.rs485_supported = (const struct serial_rs485) { };
1530 if (rs485conf->flags & SER_RS485_ENABLED) {
1531 dev_err(dev, "disabling RS-485 (rts-gpio missing in device tree)\n");
1532 memset(rs485conf, 0, sizeof(*rs485conf));
1533 }
1534 } else {
1535 gpiod_set_consumer_name(up->rts_gpiod, "omap-serial");
1536 }
1537
1538 return 0;
1539}
1540
1541static const struct serial_rs485 serial_omap_rs485_supported = {
1542 .flags = SER_RS485_ENABLED | SER_RS485_RTS_ON_SEND | SER_RS485_RTS_AFTER_SEND |
1543 SER_RS485_RX_DURING_TX,
1544 .delay_rts_before_send = 1,
1545 .delay_rts_after_send = 1,
1546};
1547
1548static int serial_omap_probe(struct platform_device *pdev)
1549{
1550 struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
1551 struct uart_omap_port *up;
1552 struct resource *mem;
1553 void __iomem *base;
1554 int uartirq = 0;
1555 int wakeirq = 0;
1556 int ret;
1557
1558 /* The optional wakeirq may be specified in the board dts file */
1559 if (pdev->dev.of_node) {
1560 uartirq = irq_of_parse_and_map(pdev->dev.of_node, 0);
1561 if (!uartirq)
1562 return -EPROBE_DEFER;
1563 wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1);
1564 omap_up_info = of_get_uart_port_info(&pdev->dev);
1565 pdev->dev.platform_data = omap_up_info;
1566 } else {
1567 uartirq = platform_get_irq(pdev, 0);
1568 if (uartirq < 0)
1569 return -EPROBE_DEFER;
1570 }
1571
1572 up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
1573 if (!up)
1574 return -ENOMEM;
1575
1576 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1577 base = devm_ioremap_resource(&pdev->dev, mem);
1578 if (IS_ERR(base))
1579 return PTR_ERR(base);
1580
1581 up->dev = &pdev->dev;
1582 up->port.dev = &pdev->dev;
1583 up->port.type = PORT_OMAP;
1584 up->port.iotype = UPIO_MEM;
1585 up->port.irq = uartirq;
1586 up->port.regshift = 2;
1587 up->port.fifosize = 64;
1588 up->port.ops = &serial_omap_pops;
1589 up->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_OMAP_CONSOLE);
1590
1591 if (pdev->dev.of_node)
1592 ret = of_alias_get_id(pdev->dev.of_node, "serial");
1593 else
1594 ret = pdev->id;
1595
1596 if (ret < 0) {
1597 dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
1598 ret);
1599 goto err_port_line;
1600 }
1601 up->port.line = ret;
1602
1603 if (up->port.line >= OMAP_MAX_HSUART_PORTS) {
1604 dev_err(&pdev->dev, "uart ID %d > MAX %d.\n", up->port.line,
1605 OMAP_MAX_HSUART_PORTS);
1606 ret = -ENXIO;
1607 goto err_port_line;
1608 }
1609
1610 up->wakeirq = wakeirq;
1611 if (!up->wakeirq)
1612 dev_info(up->port.dev, "no wakeirq for uart%d\n",
1613 up->port.line);
1614
1615 ret = serial_omap_probe_rs485(up, &pdev->dev);
1616 if (ret < 0)
1617 goto err_rs485;
1618
1619 sprintf(up->name, "OMAP UART%d", up->port.line);
1620 up->port.mapbase = mem->start;
1621 up->port.membase = base;
1622 up->port.flags = omap_up_info->flags;
1623 up->port.uartclk = omap_up_info->uartclk;
1624 up->port.rs485_config = serial_omap_config_rs485;
1625 up->port.rs485_supported = serial_omap_rs485_supported;
1626 if (!up->port.uartclk) {
1627 up->port.uartclk = DEFAULT_CLK_SPEED;
1628 dev_warn(&pdev->dev,
1629 "No clock speed specified: using default: %d\n",
1630 DEFAULT_CLK_SPEED);
1631 }
1632
1633 up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
1634 up->calc_latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
1635 cpu_latency_qos_add_request(&up->pm_qos_request, up->latency);
1636 INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
1637
1638 platform_set_drvdata(pdev, up);
1639 if (omap_up_info->autosuspend_timeout == 0)
1640 omap_up_info->autosuspend_timeout = -1;
1641
1642 device_init_wakeup(up->dev, true);
1643
1644 pm_runtime_enable(&pdev->dev);
1645
1646 pm_runtime_get_sync(&pdev->dev);
1647
1648 omap_serial_fill_features_erratas(up);
1649
1650 ui[up->port.line] = up;
1651 serial_omap_add_console_port(up);
1652
1653 ret = uart_add_one_port(&serial_omap_reg, &up->port);
1654 if (ret != 0)
1655 goto err_add_port;
1656
1657 return 0;
1658
1659err_add_port:
1660 pm_runtime_put_sync(&pdev->dev);
1661 pm_runtime_disable(&pdev->dev);
1662 cpu_latency_qos_remove_request(&up->pm_qos_request);
1663 device_init_wakeup(up->dev, false);
1664err_rs485:
1665err_port_line:
1666 return ret;
1667}
1668
1669static int serial_omap_remove(struct platform_device *dev)
1670{
1671 struct uart_omap_port *up = platform_get_drvdata(dev);
1672
1673 pm_runtime_get_sync(up->dev);
1674
1675 uart_remove_one_port(&serial_omap_reg, &up->port);
1676
1677 pm_runtime_put_sync(up->dev);
1678 pm_runtime_disable(up->dev);
1679 cpu_latency_qos_remove_request(&up->pm_qos_request);
1680 device_init_wakeup(&dev->dev, false);
1681
1682 return 0;
1683}
1684
1685/*
1686 * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
1687 * The access to uart register after MDR1 Access
1688 * causes UART to corrupt data.
1689 *
1690 * Need a delay =
1691 * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
1692 * give 10 times as much
1693 */
1694static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
1695{
1696 u8 timeout = 255;
1697
1698 serial_out(up, UART_OMAP_MDR1, mdr1);
1699 udelay(2);
1700 serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
1701 UART_FCR_CLEAR_RCVR);
1702 /*
1703 * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
1704 * TX_FIFO_E bit is 1.
1705 */
1706 while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
1707 (UART_LSR_THRE | UART_LSR_DR))) {
1708 timeout--;
1709 if (!timeout) {
1710 /* Should *never* happen. we warn and carry on */
1711 dev_crit(up->dev, "Errata i202: timedout %x\n",
1712 serial_in(up, UART_LSR));
1713 break;
1714 }
1715 udelay(1);
1716 }
1717}
1718
1719#ifdef CONFIG_PM
1720static void serial_omap_restore_context(struct uart_omap_port *up)
1721{
1722 if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1723 serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
1724 else
1725 serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1726
1727 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1728 serial_out(up, UART_EFR, UART_EFR_ECB);
1729 serial_out(up, UART_LCR, 0x0); /* Operational mode */
1730 serial_out(up, UART_IER, 0x0);
1731 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1732 serial_out(up, UART_DLL, up->dll);
1733 serial_out(up, UART_DLM, up->dlh);
1734 serial_out(up, UART_LCR, 0x0); /* Operational mode */
1735 serial_out(up, UART_IER, up->ier);
1736 serial_out(up, UART_FCR, up->fcr);
1737 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1738 serial_out(up, UART_MCR, up->mcr);
1739 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1740 serial_out(up, UART_OMAP_SCR, up->scr);
1741 serial_out(up, UART_EFR, up->efr);
1742 serial_out(up, UART_LCR, up->lcr);
1743 if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1744 serial_omap_mdr1_errataset(up, up->mdr1);
1745 else
1746 serial_out(up, UART_OMAP_MDR1, up->mdr1);
1747 serial_out(up, UART_OMAP_WER, up->wer);
1748}
1749
1750static int serial_omap_runtime_suspend(struct device *dev)
1751{
1752 struct uart_omap_port *up = dev_get_drvdata(dev);
1753
1754 if (!up)
1755 return -EINVAL;
1756
1757 /*
1758 * When using 'no_console_suspend', the console UART must not be
1759 * suspended. Since driver suspend is managed by runtime suspend,
1760 * preventing runtime suspend (by returning error) will keep device
1761 * active during suspend.
1762 */
1763 if (up->is_suspending && !console_suspend_enabled &&
1764 uart_console(&up->port))
1765 return -EBUSY;
1766
1767 up->context_loss_cnt = serial_omap_get_context_loss_count(up);
1768
1769 serial_omap_enable_wakeup(up, true);
1770
1771 up->latency = PM_QOS_CPU_LATENCY_DEFAULT_VALUE;
1772 schedule_work(&up->qos_work);
1773
1774 return 0;
1775}
1776
1777static int serial_omap_runtime_resume(struct device *dev)
1778{
1779 struct uart_omap_port *up = dev_get_drvdata(dev);
1780
1781 int loss_cnt = serial_omap_get_context_loss_count(up);
1782
1783 serial_omap_enable_wakeup(up, false);
1784
1785 if (loss_cnt < 0) {
1786 dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n",
1787 loss_cnt);
1788 serial_omap_restore_context(up);
1789 } else if (up->context_loss_cnt != loss_cnt) {
1790 serial_omap_restore_context(up);
1791 }
1792 up->latency = up->calc_latency;
1793 schedule_work(&up->qos_work);
1794
1795 return 0;
1796}
1797#endif
1798
1799static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1800 SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1801 SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1802 serial_omap_runtime_resume, NULL)
1803 .prepare = serial_omap_prepare,
1804 .complete = serial_omap_complete,
1805};
1806
1807#if defined(CONFIG_OF)
1808static const struct of_device_id omap_serial_of_match[] = {
1809 { .compatible = "ti,omap2-uart" },
1810 { .compatible = "ti,omap3-uart" },
1811 { .compatible = "ti,omap4-uart" },
1812 {},
1813};
1814MODULE_DEVICE_TABLE(of, omap_serial_of_match);
1815#endif
1816
1817static struct platform_driver serial_omap_driver = {
1818 .probe = serial_omap_probe,
1819 .remove = serial_omap_remove,
1820 .driver = {
1821 .name = OMAP_SERIAL_DRIVER_NAME,
1822 .pm = &serial_omap_dev_pm_ops,
1823 .of_match_table = of_match_ptr(omap_serial_of_match),
1824 },
1825};
1826
1827static int __init serial_omap_init(void)
1828{
1829 int ret;
1830
1831 ret = uart_register_driver(&serial_omap_reg);
1832 if (ret != 0)
1833 return ret;
1834 ret = platform_driver_register(&serial_omap_driver);
1835 if (ret != 0)
1836 uart_unregister_driver(&serial_omap_reg);
1837 return ret;
1838}
1839
1840static void __exit serial_omap_exit(void)
1841{
1842 platform_driver_unregister(&serial_omap_driver);
1843 uart_unregister_driver(&serial_omap_reg);
1844}
1845
1846module_init(serial_omap_init);
1847module_exit(serial_omap_exit);
1848
1849MODULE_DESCRIPTION("OMAP High Speed UART driver");
1850MODULE_LICENSE("GPL");
1851MODULE_AUTHOR("Texas Instruments Inc");
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
41#include <plat/dma.h>
42#include <plat/dmtimer.h>
43#include <plat/omap-serial.h>
44
45static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
46
47/* Forward declaration of functions */
48static void uart_tx_dma_callback(int lch, u16 ch_status, void *data);
49static void serial_omap_rx_timeout(unsigned long uart_no);
50static int serial_omap_start_rxdma(struct uart_omap_port *up);
51
52static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
53{
54 offset <<= up->port.regshift;
55 return readw(up->port.membase + offset);
56}
57
58static inline void serial_out(struct uart_omap_port *up, int offset, int value)
59{
60 offset <<= up->port.regshift;
61 writew(value, up->port.membase + offset);
62}
63
64static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
65{
66 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
67 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
68 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
69 serial_out(up, UART_FCR, 0);
70}
71
72/*
73 * serial_omap_get_divisor - calculate divisor value
74 * @port: uart port info
75 * @baud: baudrate for which divisor needs to be calculated.
76 *
77 * We have written our own function to get the divisor so as to support
78 * 13x mode. 3Mbps Baudrate as an different divisor.
79 * Reference OMAP TRM Chapter 17:
80 * Table 17-1. UART Mode Baud Rates, Divisor Values, and Error Rates
81 * referring to oversampling - divisor value
82 * baudrate 460,800 to 3,686,400 all have divisor 13
83 * except 3,000,000 which has divisor value 16
84 */
85static unsigned int
86serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
87{
88 unsigned int divisor;
89
90 if (baud > OMAP_MODE13X_SPEED && baud != 3000000)
91 divisor = 13;
92 else
93 divisor = 16;
94 return port->uartclk/(baud * divisor);
95}
96
97static void serial_omap_stop_rxdma(struct uart_omap_port *up)
98{
99 if (up->uart_dma.rx_dma_used) {
100 del_timer(&up->uart_dma.rx_timer);
101 omap_stop_dma(up->uart_dma.rx_dma_channel);
102 omap_free_dma(up->uart_dma.rx_dma_channel);
103 up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE;
104 up->uart_dma.rx_dma_used = false;
105 }
106}
107
108static void serial_omap_enable_ms(struct uart_port *port)
109{
110 struct uart_omap_port *up = (struct uart_omap_port *)port;
111
112 dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->pdev->id);
113 up->ier |= UART_IER_MSI;
114 serial_out(up, UART_IER, up->ier);
115}
116
117static void serial_omap_stop_tx(struct uart_port *port)
118{
119 struct uart_omap_port *up = (struct uart_omap_port *)port;
120
121 if (up->use_dma &&
122 up->uart_dma.tx_dma_channel != OMAP_UART_DMA_CH_FREE) {
123 /*
124 * Check if dma is still active. If yes do nothing,
125 * return. Else stop dma
126 */
127 if (omap_get_dma_active_status(up->uart_dma.tx_dma_channel))
128 return;
129 omap_stop_dma(up->uart_dma.tx_dma_channel);
130 omap_free_dma(up->uart_dma.tx_dma_channel);
131 up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE;
132 }
133
134 if (up->ier & UART_IER_THRI) {
135 up->ier &= ~UART_IER_THRI;
136 serial_out(up, UART_IER, up->ier);
137 }
138}
139
140static void serial_omap_stop_rx(struct uart_port *port)
141{
142 struct uart_omap_port *up = (struct uart_omap_port *)port;
143
144 if (up->use_dma)
145 serial_omap_stop_rxdma(up);
146 up->ier &= ~UART_IER_RLSI;
147 up->port.read_status_mask &= ~UART_LSR_DR;
148 serial_out(up, UART_IER, up->ier);
149}
150
151static inline void receive_chars(struct uart_omap_port *up, int *status)
152{
153 struct tty_struct *tty = up->port.state->port.tty;
154 unsigned int flag;
155 unsigned char ch, lsr = *status;
156 int max_count = 256;
157
158 do {
159 if (likely(lsr & UART_LSR_DR))
160 ch = serial_in(up, UART_RX);
161 flag = TTY_NORMAL;
162 up->port.icount.rx++;
163
164 if (unlikely(lsr & UART_LSR_BRK_ERROR_BITS)) {
165 /*
166 * For statistics only
167 */
168 if (lsr & UART_LSR_BI) {
169 lsr &= ~(UART_LSR_FE | UART_LSR_PE);
170 up->port.icount.brk++;
171 /*
172 * We do the SysRQ and SAK checking
173 * here because otherwise the break
174 * may get masked by ignore_status_mask
175 * or read_status_mask.
176 */
177 if (uart_handle_break(&up->port))
178 goto ignore_char;
179 } else if (lsr & UART_LSR_PE) {
180 up->port.icount.parity++;
181 } else if (lsr & UART_LSR_FE) {
182 up->port.icount.frame++;
183 }
184
185 if (lsr & UART_LSR_OE)
186 up->port.icount.overrun++;
187
188 /*
189 * Mask off conditions which should be ignored.
190 */
191 lsr &= up->port.read_status_mask;
192
193#ifdef CONFIG_SERIAL_OMAP_CONSOLE
194 if (up->port.line == up->port.cons->index) {
195 /* Recover the break flag from console xmit */
196 lsr |= up->lsr_break_flag;
197 }
198#endif
199 if (lsr & UART_LSR_BI)
200 flag = TTY_BREAK;
201 else if (lsr & UART_LSR_PE)
202 flag = TTY_PARITY;
203 else if (lsr & UART_LSR_FE)
204 flag = TTY_FRAME;
205 }
206
207 if (uart_handle_sysrq_char(&up->port, ch))
208 goto ignore_char;
209 uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
210ignore_char:
211 lsr = serial_in(up, UART_LSR);
212 } while ((lsr & (UART_LSR_DR | UART_LSR_BI)) && (max_count-- > 0));
213 spin_unlock(&up->port.lock);
214 tty_flip_buffer_push(tty);
215 spin_lock(&up->port.lock);
216}
217
218static void transmit_chars(struct uart_omap_port *up)
219{
220 struct circ_buf *xmit = &up->port.state->xmit;
221 int count;
222
223 if (up->port.x_char) {
224 serial_out(up, UART_TX, up->port.x_char);
225 up->port.icount.tx++;
226 up->port.x_char = 0;
227 return;
228 }
229 if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
230 serial_omap_stop_tx(&up->port);
231 return;
232 }
233 count = up->port.fifosize / 4;
234 do {
235 serial_out(up, UART_TX, xmit->buf[xmit->tail]);
236 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
237 up->port.icount.tx++;
238 if (uart_circ_empty(xmit))
239 break;
240 } while (--count > 0);
241
242 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
243 uart_write_wakeup(&up->port);
244
245 if (uart_circ_empty(xmit))
246 serial_omap_stop_tx(&up->port);
247}
248
249static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
250{
251 if (!(up->ier & UART_IER_THRI)) {
252 up->ier |= UART_IER_THRI;
253 serial_out(up, UART_IER, up->ier);
254 }
255}
256
257static void serial_omap_start_tx(struct uart_port *port)
258{
259 struct uart_omap_port *up = (struct uart_omap_port *)port;
260 struct circ_buf *xmit;
261 unsigned int start;
262 int ret = 0;
263
264 if (!up->use_dma) {
265 serial_omap_enable_ier_thri(up);
266 return;
267 }
268
269 if (up->uart_dma.tx_dma_used)
270 return;
271
272 xmit = &up->port.state->xmit;
273
274 if (up->uart_dma.tx_dma_channel == OMAP_UART_DMA_CH_FREE) {
275 ret = omap_request_dma(up->uart_dma.uart_dma_tx,
276 "UART Tx DMA",
277 (void *)uart_tx_dma_callback, up,
278 &(up->uart_dma.tx_dma_channel));
279
280 if (ret < 0) {
281 serial_omap_enable_ier_thri(up);
282 return;
283 }
284 }
285 spin_lock(&(up->uart_dma.tx_lock));
286 up->uart_dma.tx_dma_used = true;
287 spin_unlock(&(up->uart_dma.tx_lock));
288
289 start = up->uart_dma.tx_buf_dma_phys +
290 (xmit->tail & (UART_XMIT_SIZE - 1));
291
292 up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit);
293 /*
294 * It is a circular buffer. See if the buffer has wounded back.
295 * If yes it will have to be transferred in two separate dma
296 * transfers
297 */
298 if (start + up->uart_dma.tx_buf_size >=
299 up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE)
300 up->uart_dma.tx_buf_size =
301 (up->uart_dma.tx_buf_dma_phys +
302 UART_XMIT_SIZE) - start;
303
304 omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0,
305 OMAP_DMA_AMODE_CONSTANT,
306 up->uart_dma.uart_base, 0, 0);
307 omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0,
308 OMAP_DMA_AMODE_POST_INC, start, 0, 0);
309 omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel,
310 OMAP_DMA_DATA_TYPE_S8,
311 up->uart_dma.tx_buf_size, 1,
312 OMAP_DMA_SYNC_ELEMENT,
313 up->uart_dma.uart_dma_tx, 0);
314 /* FIXME: Cache maintenance needed here? */
315 omap_start_dma(up->uart_dma.tx_dma_channel);
316}
317
318static unsigned int check_modem_status(struct uart_omap_port *up)
319{
320 unsigned int status;
321
322 status = serial_in(up, UART_MSR);
323 status |= up->msr_saved_flags;
324 up->msr_saved_flags = 0;
325 if ((status & UART_MSR_ANY_DELTA) == 0)
326 return status;
327
328 if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
329 up->port.state != NULL) {
330 if (status & UART_MSR_TERI)
331 up->port.icount.rng++;
332 if (status & UART_MSR_DDSR)
333 up->port.icount.dsr++;
334 if (status & UART_MSR_DDCD)
335 uart_handle_dcd_change
336 (&up->port, status & UART_MSR_DCD);
337 if (status & UART_MSR_DCTS)
338 uart_handle_cts_change
339 (&up->port, status & UART_MSR_CTS);
340 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
341 }
342
343 return status;
344}
345
346/**
347 * serial_omap_irq() - This handles the interrupt from one port
348 * @irq: uart port irq number
349 * @dev_id: uart port info
350 */
351static inline irqreturn_t serial_omap_irq(int irq, void *dev_id)
352{
353 struct uart_omap_port *up = dev_id;
354 unsigned int iir, lsr;
355 unsigned long flags;
356
357 iir = serial_in(up, UART_IIR);
358 if (iir & UART_IIR_NO_INT)
359 return IRQ_NONE;
360
361 spin_lock_irqsave(&up->port.lock, flags);
362 lsr = serial_in(up, UART_LSR);
363 if (iir & UART_IIR_RLSI) {
364 if (!up->use_dma) {
365 if (lsr & UART_LSR_DR)
366 receive_chars(up, &lsr);
367 } else {
368 up->ier &= ~(UART_IER_RDI | UART_IER_RLSI);
369 serial_out(up, UART_IER, up->ier);
370 if ((serial_omap_start_rxdma(up) != 0) &&
371 (lsr & UART_LSR_DR))
372 receive_chars(up, &lsr);
373 }
374 }
375
376 check_modem_status(up);
377 if ((lsr & UART_LSR_THRE) && (iir & UART_IIR_THRI))
378 transmit_chars(up);
379
380 spin_unlock_irqrestore(&up->port.lock, flags);
381 up->port_activity = jiffies;
382 return IRQ_HANDLED;
383}
384
385static unsigned int serial_omap_tx_empty(struct uart_port *port)
386{
387 struct uart_omap_port *up = (struct uart_omap_port *)port;
388 unsigned long flags = 0;
389 unsigned int ret = 0;
390
391 dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->pdev->id);
392 spin_lock_irqsave(&up->port.lock, flags);
393 ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
394 spin_unlock_irqrestore(&up->port.lock, flags);
395
396 return ret;
397}
398
399static unsigned int serial_omap_get_mctrl(struct uart_port *port)
400{
401 struct uart_omap_port *up = (struct uart_omap_port *)port;
402 unsigned char status;
403 unsigned int ret = 0;
404
405 status = check_modem_status(up);
406 dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->pdev->id);
407
408 if (status & UART_MSR_DCD)
409 ret |= TIOCM_CAR;
410 if (status & UART_MSR_RI)
411 ret |= TIOCM_RNG;
412 if (status & UART_MSR_DSR)
413 ret |= TIOCM_DSR;
414 if (status & UART_MSR_CTS)
415 ret |= TIOCM_CTS;
416 return ret;
417}
418
419static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
420{
421 struct uart_omap_port *up = (struct uart_omap_port *)port;
422 unsigned char mcr = 0;
423
424 dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->pdev->id);
425 if (mctrl & TIOCM_RTS)
426 mcr |= UART_MCR_RTS;
427 if (mctrl & TIOCM_DTR)
428 mcr |= UART_MCR_DTR;
429 if (mctrl & TIOCM_OUT1)
430 mcr |= UART_MCR_OUT1;
431 if (mctrl & TIOCM_OUT2)
432 mcr |= UART_MCR_OUT2;
433 if (mctrl & TIOCM_LOOP)
434 mcr |= UART_MCR_LOOP;
435
436 mcr |= up->mcr;
437 serial_out(up, UART_MCR, mcr);
438}
439
440static void serial_omap_break_ctl(struct uart_port *port, int break_state)
441{
442 struct uart_omap_port *up = (struct uart_omap_port *)port;
443 unsigned long flags = 0;
444
445 dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->pdev->id);
446 spin_lock_irqsave(&up->port.lock, flags);
447 if (break_state == -1)
448 up->lcr |= UART_LCR_SBC;
449 else
450 up->lcr &= ~UART_LCR_SBC;
451 serial_out(up, UART_LCR, up->lcr);
452 spin_unlock_irqrestore(&up->port.lock, flags);
453}
454
455static int serial_omap_startup(struct uart_port *port)
456{
457 struct uart_omap_port *up = (struct uart_omap_port *)port;
458 unsigned long flags = 0;
459 int retval;
460
461 /*
462 * Allocate the IRQ
463 */
464 retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
465 up->name, up);
466 if (retval)
467 return retval;
468
469 dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->pdev->id);
470
471 /*
472 * Clear the FIFO buffers and disable them.
473 * (they will be reenabled in set_termios())
474 */
475 serial_omap_clear_fifos(up);
476 /* For Hardware flow control */
477 serial_out(up, UART_MCR, UART_MCR_RTS);
478
479 /*
480 * Clear the interrupt registers.
481 */
482 (void) serial_in(up, UART_LSR);
483 if (serial_in(up, UART_LSR) & UART_LSR_DR)
484 (void) serial_in(up, UART_RX);
485 (void) serial_in(up, UART_IIR);
486 (void) serial_in(up, UART_MSR);
487
488 /*
489 * Now, initialize the UART
490 */
491 serial_out(up, UART_LCR, UART_LCR_WLEN8);
492 spin_lock_irqsave(&up->port.lock, flags);
493 /*
494 * Most PC uarts need OUT2 raised to enable interrupts.
495 */
496 up->port.mctrl |= TIOCM_OUT2;
497 serial_omap_set_mctrl(&up->port, up->port.mctrl);
498 spin_unlock_irqrestore(&up->port.lock, flags);
499
500 up->msr_saved_flags = 0;
501 if (up->use_dma) {
502 free_page((unsigned long)up->port.state->xmit.buf);
503 up->port.state->xmit.buf = dma_alloc_coherent(NULL,
504 UART_XMIT_SIZE,
505 (dma_addr_t *)&(up->uart_dma.tx_buf_dma_phys),
506 0);
507 init_timer(&(up->uart_dma.rx_timer));
508 up->uart_dma.rx_timer.function = serial_omap_rx_timeout;
509 up->uart_dma.rx_timer.data = up->pdev->id;
510 /* Currently the buffer size is 4KB. Can increase it */
511 up->uart_dma.rx_buf = dma_alloc_coherent(NULL,
512 up->uart_dma.rx_buf_size,
513 (dma_addr_t *)&(up->uart_dma.rx_buf_dma_phys), 0);
514 }
515 /*
516 * Finally, enable interrupts. Note: Modem status interrupts
517 * are set via set_termios(), which will be occurring imminently
518 * anyway, so we don't enable them here.
519 */
520 up->ier = UART_IER_RLSI | UART_IER_RDI;
521 serial_out(up, UART_IER, up->ier);
522
523 /* Enable module level wake up */
524 serial_out(up, UART_OMAP_WER, OMAP_UART_WER_MOD_WKUP);
525
526 up->port_activity = jiffies;
527 return 0;
528}
529
530static void serial_omap_shutdown(struct uart_port *port)
531{
532 struct uart_omap_port *up = (struct uart_omap_port *)port;
533 unsigned long flags = 0;
534
535 dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->pdev->id);
536 /*
537 * Disable interrupts from this port
538 */
539 up->ier = 0;
540 serial_out(up, UART_IER, 0);
541
542 spin_lock_irqsave(&up->port.lock, flags);
543 up->port.mctrl &= ~TIOCM_OUT2;
544 serial_omap_set_mctrl(&up->port, up->port.mctrl);
545 spin_unlock_irqrestore(&up->port.lock, flags);
546
547 /*
548 * Disable break condition and FIFOs
549 */
550 serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
551 serial_omap_clear_fifos(up);
552
553 /*
554 * Read data port to reset things, and then free the irq
555 */
556 if (serial_in(up, UART_LSR) & UART_LSR_DR)
557 (void) serial_in(up, UART_RX);
558 if (up->use_dma) {
559 dma_free_coherent(up->port.dev,
560 UART_XMIT_SIZE, up->port.state->xmit.buf,
561 up->uart_dma.tx_buf_dma_phys);
562 up->port.state->xmit.buf = NULL;
563 serial_omap_stop_rx(port);
564 dma_free_coherent(up->port.dev,
565 up->uart_dma.rx_buf_size, up->uart_dma.rx_buf,
566 up->uart_dma.rx_buf_dma_phys);
567 up->uart_dma.rx_buf = NULL;
568 }
569 free_irq(up->port.irq, up);
570}
571
572static inline void
573serial_omap_configure_xonxoff
574 (struct uart_omap_port *up, struct ktermios *termios)
575{
576 unsigned char efr = 0;
577
578 up->lcr = serial_in(up, UART_LCR);
579 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
580 up->efr = serial_in(up, UART_EFR);
581 serial_out(up, UART_EFR, up->efr & ~UART_EFR_ECB);
582
583 serial_out(up, UART_XON1, termios->c_cc[VSTART]);
584 serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
585
586 /* clear SW control mode bits */
587 efr = up->efr;
588 efr &= OMAP_UART_SW_CLR;
589
590 /*
591 * IXON Flag:
592 * Enable XON/XOFF flow control on output.
593 * Transmit XON1, XOFF1
594 */
595 if (termios->c_iflag & IXON)
596 efr |= OMAP_UART_SW_TX;
597
598 /*
599 * IXOFF Flag:
600 * Enable XON/XOFF flow control on input.
601 * Receiver compares XON1, XOFF1.
602 */
603 if (termios->c_iflag & IXOFF)
604 efr |= OMAP_UART_SW_RX;
605
606 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
607 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
608
609 up->mcr = serial_in(up, UART_MCR);
610
611 /*
612 * IXANY Flag:
613 * Enable any character to restart output.
614 * Operation resumes after receiving any
615 * character after recognition of the XOFF character
616 */
617 if (termios->c_iflag & IXANY)
618 up->mcr |= UART_MCR_XONANY;
619
620 serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
621 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
622 serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
623 /* Enable special char function UARTi.EFR_REG[5] and
624 * load the new software flow control mode IXON or IXOFF
625 * and restore the UARTi.EFR_REG[4] ENHANCED_EN value.
626 */
627 serial_out(up, UART_EFR, efr | UART_EFR_SCD);
628 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
629
630 serial_out(up, UART_MCR, up->mcr & ~UART_MCR_TCRTLR);
631 serial_out(up, UART_LCR, up->lcr);
632}
633
634static void
635serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
636 struct ktermios *old)
637{
638 struct uart_omap_port *up = (struct uart_omap_port *)port;
639 unsigned char cval = 0;
640 unsigned char efr = 0;
641 unsigned long flags = 0;
642 unsigned int baud, quot;
643
644 switch (termios->c_cflag & CSIZE) {
645 case CS5:
646 cval = UART_LCR_WLEN5;
647 break;
648 case CS6:
649 cval = UART_LCR_WLEN6;
650 break;
651 case CS7:
652 cval = UART_LCR_WLEN7;
653 break;
654 default:
655 case CS8:
656 cval = UART_LCR_WLEN8;
657 break;
658 }
659
660 if (termios->c_cflag & CSTOPB)
661 cval |= UART_LCR_STOP;
662 if (termios->c_cflag & PARENB)
663 cval |= UART_LCR_PARITY;
664 if (!(termios->c_cflag & PARODD))
665 cval |= UART_LCR_EPAR;
666
667 /*
668 * Ask the core to calculate the divisor for us.
669 */
670
671 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
672 quot = serial_omap_get_divisor(port, baud);
673
674 up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
675 UART_FCR_ENABLE_FIFO;
676 if (up->use_dma)
677 up->fcr |= UART_FCR_DMA_SELECT;
678
679 /*
680 * Ok, we're now changing the port state. Do it with
681 * interrupts disabled.
682 */
683 spin_lock_irqsave(&up->port.lock, flags);
684
685 /*
686 * Update the per-port timeout.
687 */
688 uart_update_timeout(port, termios->c_cflag, baud);
689
690 up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
691 if (termios->c_iflag & INPCK)
692 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
693 if (termios->c_iflag & (BRKINT | PARMRK))
694 up->port.read_status_mask |= UART_LSR_BI;
695
696 /*
697 * Characters to ignore
698 */
699 up->port.ignore_status_mask = 0;
700 if (termios->c_iflag & IGNPAR)
701 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
702 if (termios->c_iflag & IGNBRK) {
703 up->port.ignore_status_mask |= UART_LSR_BI;
704 /*
705 * If we're ignoring parity and break indicators,
706 * ignore overruns too (for real raw support).
707 */
708 if (termios->c_iflag & IGNPAR)
709 up->port.ignore_status_mask |= UART_LSR_OE;
710 }
711
712 /*
713 * ignore all characters if CREAD is not set
714 */
715 if ((termios->c_cflag & CREAD) == 0)
716 up->port.ignore_status_mask |= UART_LSR_DR;
717
718 /*
719 * Modem status interrupts
720 */
721 up->ier &= ~UART_IER_MSI;
722 if (UART_ENABLE_MS(&up->port, termios->c_cflag))
723 up->ier |= UART_IER_MSI;
724 serial_out(up, UART_IER, up->ier);
725 serial_out(up, UART_LCR, cval); /* reset DLAB */
726
727 /* FIFOs and DMA Settings */
728
729 /* FCR can be changed only when the
730 * baud clock is not running
731 * DLL_REG and DLH_REG set to 0.
732 */
733 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
734 serial_out(up, UART_DLL, 0);
735 serial_out(up, UART_DLM, 0);
736 serial_out(up, UART_LCR, 0);
737
738 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
739
740 up->efr = serial_in(up, UART_EFR);
741 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
742
743 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
744 up->mcr = serial_in(up, UART_MCR);
745 serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
746 /* FIFO ENABLE, DMA MODE */
747 serial_out(up, UART_FCR, up->fcr);
748 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
749
750 if (up->use_dma) {
751 serial_out(up, UART_TI752_TLR, 0);
752 serial_out(up, UART_OMAP_SCR,
753 (UART_FCR_TRIGGER_4 | UART_FCR_TRIGGER_8));
754 }
755
756 serial_out(up, UART_EFR, up->efr);
757 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
758 serial_out(up, UART_MCR, up->mcr);
759
760 /* Protocol, Baud Rate, and Interrupt Settings */
761
762 serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
763 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
764
765 up->efr = serial_in(up, UART_EFR);
766 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
767
768 serial_out(up, UART_LCR, 0);
769 serial_out(up, UART_IER, 0);
770 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
771
772 serial_out(up, UART_DLL, quot & 0xff); /* LS of divisor */
773 serial_out(up, UART_DLM, quot >> 8); /* MS of divisor */
774
775 serial_out(up, UART_LCR, 0);
776 serial_out(up, UART_IER, up->ier);
777 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
778
779 serial_out(up, UART_EFR, up->efr);
780 serial_out(up, UART_LCR, cval);
781
782 if (baud > 230400 && baud != 3000000)
783 serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_13X_MODE);
784 else
785 serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_16X_MODE);
786
787 /* Hardware Flow Control Configuration */
788
789 if (termios->c_cflag & CRTSCTS) {
790 efr |= (UART_EFR_CTS | UART_EFR_RTS);
791 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
792
793 up->mcr = serial_in(up, UART_MCR);
794 serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
795
796 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
797 up->efr = serial_in(up, UART_EFR);
798 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
799
800 serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
801 serial_out(up, UART_EFR, efr); /* Enable AUTORTS and AUTOCTS */
802 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
803 serial_out(up, UART_MCR, up->mcr | UART_MCR_RTS);
804 serial_out(up, UART_LCR, cval);
805 }
806
807 serial_omap_set_mctrl(&up->port, up->port.mctrl);
808 /* Software Flow Control Configuration */
809 serial_omap_configure_xonxoff(up, termios);
810
811 spin_unlock_irqrestore(&up->port.lock, flags);
812 dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->pdev->id);
813}
814
815static void
816serial_omap_pm(struct uart_port *port, unsigned int state,
817 unsigned int oldstate)
818{
819 struct uart_omap_port *up = (struct uart_omap_port *)port;
820 unsigned char efr;
821
822 dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->pdev->id);
823 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
824 efr = serial_in(up, UART_EFR);
825 serial_out(up, UART_EFR, efr | UART_EFR_ECB);
826 serial_out(up, UART_LCR, 0);
827
828 serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
829 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
830 serial_out(up, UART_EFR, efr);
831 serial_out(up, UART_LCR, 0);
832}
833
834static void serial_omap_release_port(struct uart_port *port)
835{
836 dev_dbg(port->dev, "serial_omap_release_port+\n");
837}
838
839static int serial_omap_request_port(struct uart_port *port)
840{
841 dev_dbg(port->dev, "serial_omap_request_port+\n");
842 return 0;
843}
844
845static void serial_omap_config_port(struct uart_port *port, int flags)
846{
847 struct uart_omap_port *up = (struct uart_omap_port *)port;
848
849 dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
850 up->pdev->id);
851 up->port.type = PORT_OMAP;
852}
853
854static int
855serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
856{
857 /* we don't want the core code to modify any port params */
858 dev_dbg(port->dev, "serial_omap_verify_port+\n");
859 return -EINVAL;
860}
861
862static const char *
863serial_omap_type(struct uart_port *port)
864{
865 struct uart_omap_port *up = (struct uart_omap_port *)port;
866
867 dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->pdev->id);
868 return up->name;
869}
870
871#define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
872
873static inline void wait_for_xmitr(struct uart_omap_port *up)
874{
875 unsigned int status, tmout = 10000;
876
877 /* Wait up to 10ms for the character(s) to be sent. */
878 do {
879 status = serial_in(up, UART_LSR);
880
881 if (status & UART_LSR_BI)
882 up->lsr_break_flag = UART_LSR_BI;
883
884 if (--tmout == 0)
885 break;
886 udelay(1);
887 } while ((status & BOTH_EMPTY) != BOTH_EMPTY);
888
889 /* Wait up to 1s for flow control if necessary */
890 if (up->port.flags & UPF_CONS_FLOW) {
891 tmout = 1000000;
892 for (tmout = 1000000; tmout; tmout--) {
893 unsigned int msr = serial_in(up, UART_MSR);
894
895 up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
896 if (msr & UART_MSR_CTS)
897 break;
898
899 udelay(1);
900 }
901 }
902}
903
904#ifdef CONFIG_CONSOLE_POLL
905
906static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
907{
908 struct uart_omap_port *up = (struct uart_omap_port *)port;
909 wait_for_xmitr(up);
910 serial_out(up, UART_TX, ch);
911}
912
913static int serial_omap_poll_get_char(struct uart_port *port)
914{
915 struct uart_omap_port *up = (struct uart_omap_port *)port;
916 unsigned int status = serial_in(up, UART_LSR);
917
918 if (!(status & UART_LSR_DR))
919 return NO_POLL_CHAR;
920
921 return serial_in(up, UART_RX);
922}
923
924#endif /* CONFIG_CONSOLE_POLL */
925
926#ifdef CONFIG_SERIAL_OMAP_CONSOLE
927
928static struct uart_omap_port *serial_omap_console_ports[4];
929
930static struct uart_driver serial_omap_reg;
931
932static void serial_omap_console_putchar(struct uart_port *port, int ch)
933{
934 struct uart_omap_port *up = (struct uart_omap_port *)port;
935
936 wait_for_xmitr(up);
937 serial_out(up, UART_TX, ch);
938}
939
940static void
941serial_omap_console_write(struct console *co, const char *s,
942 unsigned int count)
943{
944 struct uart_omap_port *up = serial_omap_console_ports[co->index];
945 unsigned long flags;
946 unsigned int ier;
947 int locked = 1;
948
949 local_irq_save(flags);
950 if (up->port.sysrq)
951 locked = 0;
952 else if (oops_in_progress)
953 locked = spin_trylock(&up->port.lock);
954 else
955 spin_lock(&up->port.lock);
956
957 /*
958 * First save the IER then disable the interrupts
959 */
960 ier = serial_in(up, UART_IER);
961 serial_out(up, UART_IER, 0);
962
963 uart_console_write(&up->port, s, count, serial_omap_console_putchar);
964
965 /*
966 * Finally, wait for transmitter to become empty
967 * and restore the IER
968 */
969 wait_for_xmitr(up);
970 serial_out(up, UART_IER, ier);
971 /*
972 * The receive handling will happen properly because the
973 * receive ready bit will still be set; it is not cleared
974 * on read. However, modem control will not, we must
975 * call it if we have saved something in the saved flags
976 * while processing with interrupts off.
977 */
978 if (up->msr_saved_flags)
979 check_modem_status(up);
980
981 if (locked)
982 spin_unlock(&up->port.lock);
983 local_irq_restore(flags);
984}
985
986static int __init
987serial_omap_console_setup(struct console *co, char *options)
988{
989 struct uart_omap_port *up;
990 int baud = 115200;
991 int bits = 8;
992 int parity = 'n';
993 int flow = 'n';
994
995 if (serial_omap_console_ports[co->index] == NULL)
996 return -ENODEV;
997 up = serial_omap_console_ports[co->index];
998
999 if (options)
1000 uart_parse_options(options, &baud, &parity, &bits, &flow);
1001
1002 return uart_set_options(&up->port, co, baud, parity, bits, flow);
1003}
1004
1005static struct console serial_omap_console = {
1006 .name = OMAP_SERIAL_NAME,
1007 .write = serial_omap_console_write,
1008 .device = uart_console_device,
1009 .setup = serial_omap_console_setup,
1010 .flags = CON_PRINTBUFFER,
1011 .index = -1,
1012 .data = &serial_omap_reg,
1013};
1014
1015static void serial_omap_add_console_port(struct uart_omap_port *up)
1016{
1017 serial_omap_console_ports[up->pdev->id] = up;
1018}
1019
1020#define OMAP_CONSOLE (&serial_omap_console)
1021
1022#else
1023
1024#define OMAP_CONSOLE NULL
1025
1026static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1027{}
1028
1029#endif
1030
1031static struct uart_ops serial_omap_pops = {
1032 .tx_empty = serial_omap_tx_empty,
1033 .set_mctrl = serial_omap_set_mctrl,
1034 .get_mctrl = serial_omap_get_mctrl,
1035 .stop_tx = serial_omap_stop_tx,
1036 .start_tx = serial_omap_start_tx,
1037 .stop_rx = serial_omap_stop_rx,
1038 .enable_ms = serial_omap_enable_ms,
1039 .break_ctl = serial_omap_break_ctl,
1040 .startup = serial_omap_startup,
1041 .shutdown = serial_omap_shutdown,
1042 .set_termios = serial_omap_set_termios,
1043 .pm = serial_omap_pm,
1044 .type = serial_omap_type,
1045 .release_port = serial_omap_release_port,
1046 .request_port = serial_omap_request_port,
1047 .config_port = serial_omap_config_port,
1048 .verify_port = serial_omap_verify_port,
1049#ifdef CONFIG_CONSOLE_POLL
1050 .poll_put_char = serial_omap_poll_put_char,
1051 .poll_get_char = serial_omap_poll_get_char,
1052#endif
1053};
1054
1055static struct uart_driver serial_omap_reg = {
1056 .owner = THIS_MODULE,
1057 .driver_name = "OMAP-SERIAL",
1058 .dev_name = OMAP_SERIAL_NAME,
1059 .nr = OMAP_MAX_HSUART_PORTS,
1060 .cons = OMAP_CONSOLE,
1061};
1062
1063static int
1064serial_omap_suspend(struct platform_device *pdev, pm_message_t state)
1065{
1066 struct uart_omap_port *up = platform_get_drvdata(pdev);
1067
1068 if (up)
1069 uart_suspend_port(&serial_omap_reg, &up->port);
1070 return 0;
1071}
1072
1073static int serial_omap_resume(struct platform_device *dev)
1074{
1075 struct uart_omap_port *up = platform_get_drvdata(dev);
1076
1077 if (up)
1078 uart_resume_port(&serial_omap_reg, &up->port);
1079 return 0;
1080}
1081
1082static void serial_omap_rx_timeout(unsigned long uart_no)
1083{
1084 struct uart_omap_port *up = ui[uart_no];
1085 unsigned int curr_dma_pos, curr_transmitted_size;
1086 int ret = 0;
1087
1088 curr_dma_pos = omap_get_dma_dst_pos(up->uart_dma.rx_dma_channel);
1089 if ((curr_dma_pos == up->uart_dma.prev_rx_dma_pos) ||
1090 (curr_dma_pos == 0)) {
1091 if (jiffies_to_msecs(jiffies - up->port_activity) <
1092 RX_TIMEOUT) {
1093 mod_timer(&up->uart_dma.rx_timer, jiffies +
1094 usecs_to_jiffies(up->uart_dma.rx_timeout));
1095 } else {
1096 serial_omap_stop_rxdma(up);
1097 up->ier |= (UART_IER_RDI | UART_IER_RLSI);
1098 serial_out(up, UART_IER, up->ier);
1099 }
1100 return;
1101 }
1102
1103 curr_transmitted_size = curr_dma_pos -
1104 up->uart_dma.prev_rx_dma_pos;
1105 up->port.icount.rx += curr_transmitted_size;
1106 tty_insert_flip_string(up->port.state->port.tty,
1107 up->uart_dma.rx_buf +
1108 (up->uart_dma.prev_rx_dma_pos -
1109 up->uart_dma.rx_buf_dma_phys),
1110 curr_transmitted_size);
1111 tty_flip_buffer_push(up->port.state->port.tty);
1112 up->uart_dma.prev_rx_dma_pos = curr_dma_pos;
1113 if (up->uart_dma.rx_buf_size +
1114 up->uart_dma.rx_buf_dma_phys == curr_dma_pos) {
1115 ret = serial_omap_start_rxdma(up);
1116 if (ret < 0) {
1117 serial_omap_stop_rxdma(up);
1118 up->ier |= (UART_IER_RDI | UART_IER_RLSI);
1119 serial_out(up, UART_IER, up->ier);
1120 }
1121 } else {
1122 mod_timer(&up->uart_dma.rx_timer, jiffies +
1123 usecs_to_jiffies(up->uart_dma.rx_timeout));
1124 }
1125 up->port_activity = jiffies;
1126}
1127
1128static void uart_rx_dma_callback(int lch, u16 ch_status, void *data)
1129{
1130 return;
1131}
1132
1133static int serial_omap_start_rxdma(struct uart_omap_port *up)
1134{
1135 int ret = 0;
1136
1137 if (up->uart_dma.rx_dma_channel == -1) {
1138 ret = omap_request_dma(up->uart_dma.uart_dma_rx,
1139 "UART Rx DMA",
1140 (void *)uart_rx_dma_callback, up,
1141 &(up->uart_dma.rx_dma_channel));
1142 if (ret < 0)
1143 return ret;
1144
1145 omap_set_dma_src_params(up->uart_dma.rx_dma_channel, 0,
1146 OMAP_DMA_AMODE_CONSTANT,
1147 up->uart_dma.uart_base, 0, 0);
1148 omap_set_dma_dest_params(up->uart_dma.rx_dma_channel, 0,
1149 OMAP_DMA_AMODE_POST_INC,
1150 up->uart_dma.rx_buf_dma_phys, 0, 0);
1151 omap_set_dma_transfer_params(up->uart_dma.rx_dma_channel,
1152 OMAP_DMA_DATA_TYPE_S8,
1153 up->uart_dma.rx_buf_size, 1,
1154 OMAP_DMA_SYNC_ELEMENT,
1155 up->uart_dma.uart_dma_rx, 0);
1156 }
1157 up->uart_dma.prev_rx_dma_pos = up->uart_dma.rx_buf_dma_phys;
1158 /* FIXME: Cache maintenance needed here? */
1159 omap_start_dma(up->uart_dma.rx_dma_channel);
1160 mod_timer(&up->uart_dma.rx_timer, jiffies +
1161 usecs_to_jiffies(up->uart_dma.rx_timeout));
1162 up->uart_dma.rx_dma_used = true;
1163 return ret;
1164}
1165
1166static void serial_omap_continue_tx(struct uart_omap_port *up)
1167{
1168 struct circ_buf *xmit = &up->port.state->xmit;
1169 unsigned int start = up->uart_dma.tx_buf_dma_phys
1170 + (xmit->tail & (UART_XMIT_SIZE - 1));
1171
1172 if (uart_circ_empty(xmit))
1173 return;
1174
1175 up->uart_dma.tx_buf_size = uart_circ_chars_pending(xmit);
1176 /*
1177 * It is a circular buffer. See if the buffer has wounded back.
1178 * If yes it will have to be transferred in two separate dma
1179 * transfers
1180 */
1181 if (start + up->uart_dma.tx_buf_size >=
1182 up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE)
1183 up->uart_dma.tx_buf_size =
1184 (up->uart_dma.tx_buf_dma_phys + UART_XMIT_SIZE) - start;
1185 omap_set_dma_dest_params(up->uart_dma.tx_dma_channel, 0,
1186 OMAP_DMA_AMODE_CONSTANT,
1187 up->uart_dma.uart_base, 0, 0);
1188 omap_set_dma_src_params(up->uart_dma.tx_dma_channel, 0,
1189 OMAP_DMA_AMODE_POST_INC, start, 0, 0);
1190 omap_set_dma_transfer_params(up->uart_dma.tx_dma_channel,
1191 OMAP_DMA_DATA_TYPE_S8,
1192 up->uart_dma.tx_buf_size, 1,
1193 OMAP_DMA_SYNC_ELEMENT,
1194 up->uart_dma.uart_dma_tx, 0);
1195 /* FIXME: Cache maintenance needed here? */
1196 omap_start_dma(up->uart_dma.tx_dma_channel);
1197}
1198
1199static void uart_tx_dma_callback(int lch, u16 ch_status, void *data)
1200{
1201 struct uart_omap_port *up = (struct uart_omap_port *)data;
1202 struct circ_buf *xmit = &up->port.state->xmit;
1203
1204 xmit->tail = (xmit->tail + up->uart_dma.tx_buf_size) & \
1205 (UART_XMIT_SIZE - 1);
1206 up->port.icount.tx += up->uart_dma.tx_buf_size;
1207
1208 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
1209 uart_write_wakeup(&up->port);
1210
1211 if (uart_circ_empty(xmit)) {
1212 spin_lock(&(up->uart_dma.tx_lock));
1213 serial_omap_stop_tx(&up->port);
1214 up->uart_dma.tx_dma_used = false;
1215 spin_unlock(&(up->uart_dma.tx_lock));
1216 } else {
1217 omap_stop_dma(up->uart_dma.tx_dma_channel);
1218 serial_omap_continue_tx(up);
1219 }
1220 up->port_activity = jiffies;
1221 return;
1222}
1223
1224static int serial_omap_probe(struct platform_device *pdev)
1225{
1226 struct uart_omap_port *up;
1227 struct resource *mem, *irq, *dma_tx, *dma_rx;
1228 struct omap_uart_port_info *omap_up_info = pdev->dev.platform_data;
1229 int ret = -ENOSPC;
1230
1231 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1232 if (!mem) {
1233 dev_err(&pdev->dev, "no mem resource?\n");
1234 return -ENODEV;
1235 }
1236
1237 irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
1238 if (!irq) {
1239 dev_err(&pdev->dev, "no irq resource?\n");
1240 return -ENODEV;
1241 }
1242
1243 if (!request_mem_region(mem->start, resource_size(mem),
1244 pdev->dev.driver->name)) {
1245 dev_err(&pdev->dev, "memory region already claimed\n");
1246 return -EBUSY;
1247 }
1248
1249 dma_rx = platform_get_resource_byname(pdev, IORESOURCE_DMA, "rx");
1250 if (!dma_rx) {
1251 ret = -EINVAL;
1252 goto err;
1253 }
1254
1255 dma_tx = platform_get_resource_byname(pdev, IORESOURCE_DMA, "tx");
1256 if (!dma_tx) {
1257 ret = -EINVAL;
1258 goto err;
1259 }
1260
1261 up = kzalloc(sizeof(*up), GFP_KERNEL);
1262 if (up == NULL) {
1263 ret = -ENOMEM;
1264 goto do_release_region;
1265 }
1266 sprintf(up->name, "OMAP UART%d", pdev->id);
1267 up->pdev = pdev;
1268 up->port.dev = &pdev->dev;
1269 up->port.type = PORT_OMAP;
1270 up->port.iotype = UPIO_MEM;
1271 up->port.irq = irq->start;
1272
1273 up->port.regshift = 2;
1274 up->port.fifosize = 64;
1275 up->port.ops = &serial_omap_pops;
1276 up->port.line = pdev->id;
1277
1278 up->port.membase = omap_up_info->membase;
1279 up->port.mapbase = omap_up_info->mapbase;
1280 up->port.flags = omap_up_info->flags;
1281 up->port.irqflags = omap_up_info->irqflags;
1282 up->port.uartclk = omap_up_info->uartclk;
1283 up->uart_dma.uart_base = mem->start;
1284
1285 if (omap_up_info->dma_enabled) {
1286 up->uart_dma.uart_dma_tx = dma_tx->start;
1287 up->uart_dma.uart_dma_rx = dma_rx->start;
1288 up->use_dma = 1;
1289 up->uart_dma.rx_buf_size = 4096;
1290 up->uart_dma.rx_timeout = 2;
1291 spin_lock_init(&(up->uart_dma.tx_lock));
1292 spin_lock_init(&(up->uart_dma.rx_lock));
1293 up->uart_dma.tx_dma_channel = OMAP_UART_DMA_CH_FREE;
1294 up->uart_dma.rx_dma_channel = OMAP_UART_DMA_CH_FREE;
1295 }
1296
1297 ui[pdev->id] = up;
1298 serial_omap_add_console_port(up);
1299
1300 ret = uart_add_one_port(&serial_omap_reg, &up->port);
1301 if (ret != 0)
1302 goto do_release_region;
1303
1304 platform_set_drvdata(pdev, up);
1305 return 0;
1306err:
1307 dev_err(&pdev->dev, "[UART%d]: failure [%s]: %d\n",
1308 pdev->id, __func__, ret);
1309do_release_region:
1310 release_mem_region(mem->start, resource_size(mem));
1311 return ret;
1312}
1313
1314static int serial_omap_remove(struct platform_device *dev)
1315{
1316 struct uart_omap_port *up = platform_get_drvdata(dev);
1317
1318 platform_set_drvdata(dev, NULL);
1319 if (up) {
1320 uart_remove_one_port(&serial_omap_reg, &up->port);
1321 kfree(up);
1322 }
1323 return 0;
1324}
1325
1326static struct platform_driver serial_omap_driver = {
1327 .probe = serial_omap_probe,
1328 .remove = serial_omap_remove,
1329
1330 .suspend = serial_omap_suspend,
1331 .resume = serial_omap_resume,
1332 .driver = {
1333 .name = DRIVER_NAME,
1334 },
1335};
1336
1337static int __init serial_omap_init(void)
1338{
1339 int ret;
1340
1341 ret = uart_register_driver(&serial_omap_reg);
1342 if (ret != 0)
1343 return ret;
1344 ret = platform_driver_register(&serial_omap_driver);
1345 if (ret != 0)
1346 uart_unregister_driver(&serial_omap_reg);
1347 return ret;
1348}
1349
1350static void __exit serial_omap_exit(void)
1351{
1352 platform_driver_unregister(&serial_omap_driver);
1353 uart_unregister_driver(&serial_omap_reg);
1354}
1355
1356module_init(serial_omap_init);
1357module_exit(serial_omap_exit);
1358
1359MODULE_DESCRIPTION("OMAP High Speed UART driver");
1360MODULE_LICENSE("GPL");
1361MODULE_AUTHOR("Texas Instruments Inc");