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

source code of linux/drivers/tty/serial/omap-serial.c