Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
[cris-mirror.git] / drivers / tty / serial / omap-serial.c
blob6420ae581a802fe3c614591dce7ded443e0610a6
1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Driver for OMAP-UART controller.
4 * Based on drivers/serial/8250.c
6 * Copyright (C) 2010 Texas Instruments.
8 * Authors:
9 * Govindraj R <govindraj.raja@ti.com>
10 * Thara Gopinath <thara@ti.com>
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.
19 #if defined(CONFIG_SERIAL_OMAP_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
20 #define SUPPORT_SYSRQ
21 #endif
23 #include <linux/module.h>
24 #include <linux/init.h>
25 #include <linux/console.h>
26 #include <linux/serial_reg.h>
27 #include <linux/delay.h>
28 #include <linux/slab.h>
29 #include <linux/tty.h>
30 #include <linux/tty_flip.h>
31 #include <linux/platform_device.h>
32 #include <linux/io.h>
33 #include <linux/clk.h>
34 #include <linux/serial_core.h>
35 #include <linux/irq.h>
36 #include <linux/pm_runtime.h>
37 #include <linux/pm_wakeirq.h>
38 #include <linux/of.h>
39 #include <linux/of_irq.h>
40 #include <linux/gpio.h>
41 #include <linux/of_gpio.h>
42 #include <linux/platform_data/serial-omap.h>
44 #include <dt-bindings/gpio/gpio.h>
46 #define OMAP_MAX_HSUART_PORTS 10
48 #define UART_BUILD_REVISION(x, y) (((x) << 8) | (y))
50 #define OMAP_UART_REV_42 0x0402
51 #define OMAP_UART_REV_46 0x0406
52 #define OMAP_UART_REV_52 0x0502
53 #define OMAP_UART_REV_63 0x0603
55 #define OMAP_UART_TX_WAKEUP_EN BIT(7)
57 /* Feature flags */
58 #define OMAP_UART_WER_HAS_TX_WAKEUP BIT(0)
60 #define UART_ERRATA_i202_MDR1_ACCESS BIT(0)
61 #define UART_ERRATA_i291_DMA_FORCEIDLE BIT(1)
63 #define DEFAULT_CLK_SPEED 48000000 /* 48Mhz */
65 /* SCR register bitmasks */
66 #define OMAP_UART_SCR_RX_TRIG_GRANU1_MASK (1 << 7)
67 #define OMAP_UART_SCR_TX_TRIG_GRANU1_MASK (1 << 6)
68 #define OMAP_UART_SCR_TX_EMPTY (1 << 3)
70 /* FCR register bitmasks */
71 #define OMAP_UART_FCR_RX_FIFO_TRIG_MASK (0x3 << 6)
72 #define OMAP_UART_FCR_TX_FIFO_TRIG_MASK (0x3 << 4)
74 /* MVR register bitmasks */
75 #define OMAP_UART_MVR_SCHEME_SHIFT 30
77 #define OMAP_UART_LEGACY_MVR_MAJ_MASK 0xf0
78 #define OMAP_UART_LEGACY_MVR_MAJ_SHIFT 4
79 #define OMAP_UART_LEGACY_MVR_MIN_MASK 0x0f
81 #define OMAP_UART_MVR_MAJ_MASK 0x700
82 #define OMAP_UART_MVR_MAJ_SHIFT 8
83 #define OMAP_UART_MVR_MIN_MASK 0x3f
85 #define OMAP_UART_DMA_CH_FREE -1
87 #define MSR_SAVE_FLAGS UART_MSR_ANY_DELTA
88 #define OMAP_MODE13X_SPEED 230400
90 /* WER = 0x7F
91 * Enable module level wakeup in WER reg
93 #define OMAP_UART_WER_MOD_WKUP 0x7F
95 /* Enable XON/XOFF flow control on output */
96 #define OMAP_UART_SW_TX 0x08
98 /* Enable XON/XOFF flow control on input */
99 #define OMAP_UART_SW_RX 0x02
101 #define OMAP_UART_SW_CLR 0xF0
103 #define OMAP_UART_TCR_TRIG 0x0F
105 struct uart_omap_dma {
106 u8 uart_dma_tx;
107 u8 uart_dma_rx;
108 int rx_dma_channel;
109 int tx_dma_channel;
110 dma_addr_t rx_buf_dma_phys;
111 dma_addr_t tx_buf_dma_phys;
112 unsigned int uart_base;
114 * Buffer for rx dma. It is not required for tx because the buffer
115 * comes from port structure.
117 unsigned char *rx_buf;
118 unsigned int prev_rx_dma_pos;
119 int tx_buf_size;
120 int tx_dma_used;
121 int rx_dma_used;
122 spinlock_t tx_lock;
123 spinlock_t rx_lock;
124 /* timer to poll activity on rx dma */
125 struct timer_list rx_timer;
126 unsigned int rx_buf_size;
127 unsigned int rx_poll_rate;
128 unsigned int rx_timeout;
131 struct uart_omap_port {
132 struct uart_port port;
133 struct uart_omap_dma uart_dma;
134 struct device *dev;
135 int wakeirq;
137 unsigned char ier;
138 unsigned char lcr;
139 unsigned char mcr;
140 unsigned char fcr;
141 unsigned char efr;
142 unsigned char dll;
143 unsigned char dlh;
144 unsigned char mdr1;
145 unsigned char scr;
146 unsigned char wer;
148 int use_dma;
150 * Some bits in registers are cleared on a read, so they must
151 * be saved whenever the register is read, but the bits will not
152 * be immediately processed.
154 unsigned int lsr_break_flag;
155 unsigned char msr_saved_flags;
156 char name[20];
157 unsigned long port_activity;
158 int context_loss_cnt;
159 u32 errata;
160 u32 features;
162 int rts_gpio;
164 struct pm_qos_request pm_qos_request;
165 u32 latency;
166 u32 calc_latency;
167 struct work_struct qos_work;
168 bool is_suspending;
171 #define to_uart_omap_port(p) ((container_of((p), struct uart_omap_port, port)))
173 static struct uart_omap_port *ui[OMAP_MAX_HSUART_PORTS];
175 /* Forward declaration of functions */
176 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1);
178 static inline unsigned int serial_in(struct uart_omap_port *up, int offset)
180 offset <<= up->port.regshift;
181 return readw(up->port.membase + offset);
184 static inline void serial_out(struct uart_omap_port *up, int offset, int value)
186 offset <<= up->port.regshift;
187 writew(value, up->port.membase + offset);
190 static inline void serial_omap_clear_fifos(struct uart_omap_port *up)
192 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
193 serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
194 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
195 serial_out(up, UART_FCR, 0);
198 #ifdef CONFIG_PM
199 static int serial_omap_get_context_loss_count(struct uart_omap_port *up)
201 struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
203 if (!pdata || !pdata->get_context_loss_count)
204 return -EINVAL;
206 return pdata->get_context_loss_count(up->dev);
209 /* REVISIT: Remove this when omap3 boots in device tree only mode */
210 static void serial_omap_enable_wakeup(struct uart_omap_port *up, bool enable)
212 struct omap_uart_port_info *pdata = dev_get_platdata(up->dev);
214 if (!pdata || !pdata->enable_wakeup)
215 return;
217 pdata->enable_wakeup(up->dev, enable);
219 #endif /* CONFIG_PM */
222 * Calculate the absolute difference between the desired and actual baud
223 * rate for the given mode.
225 static inline int calculate_baud_abs_diff(struct uart_port *port,
226 unsigned int baud, unsigned int mode)
228 unsigned int n = port->uartclk / (mode * baud);
229 int abs_diff;
231 if (n == 0)
232 n = 1;
234 abs_diff = baud - (port->uartclk / (mode * n));
235 if (abs_diff < 0)
236 abs_diff = -abs_diff;
238 return abs_diff;
242 * serial_omap_baud_is_mode16 - check if baud rate is MODE16X
243 * @port: uart port info
244 * @baud: baudrate for which mode needs to be determined
246 * Returns true if baud rate is MODE16X and false if MODE13X
247 * Original table in OMAP TRM named "UART Mode Baud Rates, Divisor Values,
248 * and Error Rates" determines modes not for all common baud rates.
249 * E.g. for 1000000 baud rate mode must be 16x, but according to that
250 * table it's determined as 13x.
252 static bool
253 serial_omap_baud_is_mode16(struct uart_port *port, unsigned int baud)
255 int abs_diff_13 = calculate_baud_abs_diff(port, baud, 13);
256 int abs_diff_16 = calculate_baud_abs_diff(port, baud, 16);
258 return (abs_diff_13 >= abs_diff_16);
262 * serial_omap_get_divisor - calculate divisor value
263 * @port: uart port info
264 * @baud: baudrate for which divisor needs to be calculated.
266 static unsigned int
267 serial_omap_get_divisor(struct uart_port *port, unsigned int baud)
269 unsigned int mode;
271 if (!serial_omap_baud_is_mode16(port, baud))
272 mode = 13;
273 else
274 mode = 16;
275 return port->uartclk/(mode * baud);
278 static void serial_omap_enable_ms(struct uart_port *port)
280 struct uart_omap_port *up = to_uart_omap_port(port);
282 dev_dbg(up->port.dev, "serial_omap_enable_ms+%d\n", up->port.line);
284 pm_runtime_get_sync(up->dev);
285 up->ier |= UART_IER_MSI;
286 serial_out(up, UART_IER, up->ier);
287 pm_runtime_mark_last_busy(up->dev);
288 pm_runtime_put_autosuspend(up->dev);
291 static void serial_omap_stop_tx(struct uart_port *port)
293 struct uart_omap_port *up = to_uart_omap_port(port);
294 int res;
296 pm_runtime_get_sync(up->dev);
298 /* Handle RS-485 */
299 if (port->rs485.flags & SER_RS485_ENABLED) {
300 if (up->scr & OMAP_UART_SCR_TX_EMPTY) {
301 /* THR interrupt is fired when both TX FIFO and TX
302 * shift register are empty. This means there's nothing
303 * left to transmit now, so make sure the THR interrupt
304 * is fired when TX FIFO is below the trigger level,
305 * disable THR interrupts and toggle the RS-485 GPIO
306 * data direction pin if needed.
308 up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
309 serial_out(up, UART_OMAP_SCR, up->scr);
310 res = (port->rs485.flags & SER_RS485_RTS_AFTER_SEND) ?
311 1 : 0;
312 if (gpio_get_value(up->rts_gpio) != res) {
313 if (port->rs485.delay_rts_after_send > 0)
314 mdelay(
315 port->rs485.delay_rts_after_send);
316 gpio_set_value(up->rts_gpio, res);
318 } else {
319 /* We're asked to stop, but there's still stuff in the
320 * UART FIFO, so make sure the THR interrupt is fired
321 * when both TX FIFO and TX shift register are empty.
322 * The next THR interrupt (if no transmission is started
323 * in the meantime) will indicate the end of a
324 * transmission. Therefore we _don't_ disable THR
325 * interrupts in this situation.
327 up->scr |= OMAP_UART_SCR_TX_EMPTY;
328 serial_out(up, UART_OMAP_SCR, up->scr);
329 return;
333 if (up->ier & UART_IER_THRI) {
334 up->ier &= ~UART_IER_THRI;
335 serial_out(up, UART_IER, up->ier);
338 if ((port->rs485.flags & SER_RS485_ENABLED) &&
339 !(port->rs485.flags & SER_RS485_RX_DURING_TX)) {
341 * Empty the RX FIFO, we are not interested in anything
342 * received during the half-duplex transmission.
344 serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_RCVR);
345 /* Re-enable RX interrupts */
346 up->ier |= UART_IER_RLSI | UART_IER_RDI;
347 up->port.read_status_mask |= UART_LSR_DR;
348 serial_out(up, UART_IER, up->ier);
351 pm_runtime_mark_last_busy(up->dev);
352 pm_runtime_put_autosuspend(up->dev);
355 static void serial_omap_stop_rx(struct uart_port *port)
357 struct uart_omap_port *up = to_uart_omap_port(port);
359 pm_runtime_get_sync(up->dev);
360 up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
361 up->port.read_status_mask &= ~UART_LSR_DR;
362 serial_out(up, UART_IER, up->ier);
363 pm_runtime_mark_last_busy(up->dev);
364 pm_runtime_put_autosuspend(up->dev);
367 static void transmit_chars(struct uart_omap_port *up, unsigned int lsr)
369 struct circ_buf *xmit = &up->port.state->xmit;
370 int count;
372 if (up->port.x_char) {
373 serial_out(up, UART_TX, up->port.x_char);
374 up->port.icount.tx++;
375 up->port.x_char = 0;
376 return;
378 if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
379 serial_omap_stop_tx(&up->port);
380 return;
382 count = up->port.fifosize / 4;
383 do {
384 serial_out(up, UART_TX, xmit->buf[xmit->tail]);
385 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
386 up->port.icount.tx++;
387 if (uart_circ_empty(xmit))
388 break;
389 } while (--count > 0);
391 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
392 uart_write_wakeup(&up->port);
394 if (uart_circ_empty(xmit))
395 serial_omap_stop_tx(&up->port);
398 static inline void serial_omap_enable_ier_thri(struct uart_omap_port *up)
400 if (!(up->ier & UART_IER_THRI)) {
401 up->ier |= UART_IER_THRI;
402 serial_out(up, UART_IER, up->ier);
406 static void serial_omap_start_tx(struct uart_port *port)
408 struct uart_omap_port *up = to_uart_omap_port(port);
409 int res;
411 pm_runtime_get_sync(up->dev);
413 /* Handle RS-485 */
414 if (port->rs485.flags & SER_RS485_ENABLED) {
415 /* Fire THR interrupts when FIFO is below trigger level */
416 up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
417 serial_out(up, UART_OMAP_SCR, up->scr);
419 /* if rts not already enabled */
420 res = (port->rs485.flags & SER_RS485_RTS_ON_SEND) ? 1 : 0;
421 if (gpio_get_value(up->rts_gpio) != res) {
422 gpio_set_value(up->rts_gpio, res);
423 if (port->rs485.delay_rts_before_send > 0)
424 mdelay(port->rs485.delay_rts_before_send);
428 if ((port->rs485.flags & SER_RS485_ENABLED) &&
429 !(port->rs485.flags & SER_RS485_RX_DURING_TX))
430 serial_omap_stop_rx(port);
432 serial_omap_enable_ier_thri(up);
433 pm_runtime_mark_last_busy(up->dev);
434 pm_runtime_put_autosuspend(up->dev);
437 static void serial_omap_throttle(struct uart_port *port)
439 struct uart_omap_port *up = to_uart_omap_port(port);
440 unsigned long flags;
442 pm_runtime_get_sync(up->dev);
443 spin_lock_irqsave(&up->port.lock, flags);
444 up->ier &= ~(UART_IER_RLSI | UART_IER_RDI);
445 serial_out(up, UART_IER, up->ier);
446 spin_unlock_irqrestore(&up->port.lock, flags);
447 pm_runtime_mark_last_busy(up->dev);
448 pm_runtime_put_autosuspend(up->dev);
451 static void serial_omap_unthrottle(struct uart_port *port)
453 struct uart_omap_port *up = to_uart_omap_port(port);
454 unsigned long flags;
456 pm_runtime_get_sync(up->dev);
457 spin_lock_irqsave(&up->port.lock, flags);
458 up->ier |= UART_IER_RLSI | UART_IER_RDI;
459 serial_out(up, UART_IER, up->ier);
460 spin_unlock_irqrestore(&up->port.lock, flags);
461 pm_runtime_mark_last_busy(up->dev);
462 pm_runtime_put_autosuspend(up->dev);
465 static unsigned int check_modem_status(struct uart_omap_port *up)
467 unsigned int status;
469 status = serial_in(up, UART_MSR);
470 status |= up->msr_saved_flags;
471 up->msr_saved_flags = 0;
472 if ((status & UART_MSR_ANY_DELTA) == 0)
473 return status;
475 if (status & UART_MSR_ANY_DELTA && up->ier & UART_IER_MSI &&
476 up->port.state != NULL) {
477 if (status & UART_MSR_TERI)
478 up->port.icount.rng++;
479 if (status & UART_MSR_DDSR)
480 up->port.icount.dsr++;
481 if (status & UART_MSR_DDCD)
482 uart_handle_dcd_change
483 (&up->port, status & UART_MSR_DCD);
484 if (status & UART_MSR_DCTS)
485 uart_handle_cts_change
486 (&up->port, status & UART_MSR_CTS);
487 wake_up_interruptible(&up->port.state->port.delta_msr_wait);
490 return status;
493 static void serial_omap_rlsi(struct uart_omap_port *up, unsigned int lsr)
495 unsigned int flag;
496 unsigned char ch = 0;
498 if (likely(lsr & UART_LSR_DR))
499 ch = serial_in(up, UART_RX);
501 up->port.icount.rx++;
502 flag = TTY_NORMAL;
504 if (lsr & UART_LSR_BI) {
505 flag = TTY_BREAK;
506 lsr &= ~(UART_LSR_FE | UART_LSR_PE);
507 up->port.icount.brk++;
509 * We do the SysRQ and SAK checking
510 * here because otherwise the break
511 * may get masked by ignore_status_mask
512 * or read_status_mask.
514 if (uart_handle_break(&up->port))
515 return;
519 if (lsr & UART_LSR_PE) {
520 flag = TTY_PARITY;
521 up->port.icount.parity++;
524 if (lsr & UART_LSR_FE) {
525 flag = TTY_FRAME;
526 up->port.icount.frame++;
529 if (lsr & UART_LSR_OE)
530 up->port.icount.overrun++;
532 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
533 if (up->port.line == up->port.cons->index) {
534 /* Recover the break flag from console xmit */
535 lsr |= up->lsr_break_flag;
537 #endif
538 uart_insert_char(&up->port, lsr, UART_LSR_OE, 0, flag);
541 static void serial_omap_rdi(struct uart_omap_port *up, unsigned int lsr)
543 unsigned char ch = 0;
544 unsigned int flag;
546 if (!(lsr & UART_LSR_DR))
547 return;
549 ch = serial_in(up, UART_RX);
550 flag = TTY_NORMAL;
551 up->port.icount.rx++;
553 if (uart_handle_sysrq_char(&up->port, ch))
554 return;
556 uart_insert_char(&up->port, lsr, UART_LSR_OE, ch, flag);
560 * serial_omap_irq() - This handles the interrupt from one port
561 * @irq: uart port irq number
562 * @dev_id: uart port info
564 static irqreturn_t serial_omap_irq(int irq, void *dev_id)
566 struct uart_omap_port *up = dev_id;
567 unsigned int iir, lsr;
568 unsigned int type;
569 irqreturn_t ret = IRQ_NONE;
570 int max_count = 256;
572 spin_lock(&up->port.lock);
573 pm_runtime_get_sync(up->dev);
575 do {
576 iir = serial_in(up, UART_IIR);
577 if (iir & UART_IIR_NO_INT)
578 break;
580 ret = IRQ_HANDLED;
581 lsr = serial_in(up, UART_LSR);
583 /* extract IRQ type from IIR register */
584 type = iir & 0x3e;
586 switch (type) {
587 case UART_IIR_MSI:
588 check_modem_status(up);
589 break;
590 case UART_IIR_THRI:
591 transmit_chars(up, lsr);
592 break;
593 case UART_IIR_RX_TIMEOUT:
594 /* FALLTHROUGH */
595 case UART_IIR_RDI:
596 serial_omap_rdi(up, lsr);
597 break;
598 case UART_IIR_RLSI:
599 serial_omap_rlsi(up, lsr);
600 break;
601 case UART_IIR_CTS_RTS_DSR:
602 /* simply try again */
603 break;
604 case UART_IIR_XOFF:
605 /* FALLTHROUGH */
606 default:
607 break;
609 } while (max_count--);
611 spin_unlock(&up->port.lock);
613 tty_flip_buffer_push(&up->port.state->port);
615 pm_runtime_mark_last_busy(up->dev);
616 pm_runtime_put_autosuspend(up->dev);
617 up->port_activity = jiffies;
619 return ret;
622 static unsigned int serial_omap_tx_empty(struct uart_port *port)
624 struct uart_omap_port *up = to_uart_omap_port(port);
625 unsigned long flags = 0;
626 unsigned int ret = 0;
628 pm_runtime_get_sync(up->dev);
629 dev_dbg(up->port.dev, "serial_omap_tx_empty+%d\n", up->port.line);
630 spin_lock_irqsave(&up->port.lock, flags);
631 ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
632 spin_unlock_irqrestore(&up->port.lock, flags);
633 pm_runtime_mark_last_busy(up->dev);
634 pm_runtime_put_autosuspend(up->dev);
635 return ret;
638 static unsigned int serial_omap_get_mctrl(struct uart_port *port)
640 struct uart_omap_port *up = to_uart_omap_port(port);
641 unsigned int status;
642 unsigned int ret = 0;
644 pm_runtime_get_sync(up->dev);
645 status = check_modem_status(up);
646 pm_runtime_mark_last_busy(up->dev);
647 pm_runtime_put_autosuspend(up->dev);
649 dev_dbg(up->port.dev, "serial_omap_get_mctrl+%d\n", up->port.line);
651 if (status & UART_MSR_DCD)
652 ret |= TIOCM_CAR;
653 if (status & UART_MSR_RI)
654 ret |= TIOCM_RNG;
655 if (status & UART_MSR_DSR)
656 ret |= TIOCM_DSR;
657 if (status & UART_MSR_CTS)
658 ret |= TIOCM_CTS;
659 return ret;
662 static void serial_omap_set_mctrl(struct uart_port *port, unsigned int mctrl)
664 struct uart_omap_port *up = to_uart_omap_port(port);
665 unsigned char mcr = 0, old_mcr, lcr;
667 dev_dbg(up->port.dev, "serial_omap_set_mctrl+%d\n", up->port.line);
668 if (mctrl & TIOCM_RTS)
669 mcr |= UART_MCR_RTS;
670 if (mctrl & TIOCM_DTR)
671 mcr |= UART_MCR_DTR;
672 if (mctrl & TIOCM_OUT1)
673 mcr |= UART_MCR_OUT1;
674 if (mctrl & TIOCM_OUT2)
675 mcr |= UART_MCR_OUT2;
676 if (mctrl & TIOCM_LOOP)
677 mcr |= UART_MCR_LOOP;
679 pm_runtime_get_sync(up->dev);
680 old_mcr = serial_in(up, UART_MCR);
681 old_mcr &= ~(UART_MCR_LOOP | UART_MCR_OUT2 | UART_MCR_OUT1 |
682 UART_MCR_DTR | UART_MCR_RTS);
683 up->mcr = old_mcr | mcr;
684 serial_out(up, UART_MCR, up->mcr);
686 /* Turn off autoRTS if RTS is lowered; restore autoRTS if RTS raised */
687 lcr = serial_in(up, UART_LCR);
688 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
689 if ((mctrl & TIOCM_RTS) && (port->status & UPSTAT_AUTORTS))
690 up->efr |= UART_EFR_RTS;
691 else
692 up->efr &= ~UART_EFR_RTS;
693 serial_out(up, UART_EFR, up->efr);
694 serial_out(up, UART_LCR, lcr);
696 pm_runtime_mark_last_busy(up->dev);
697 pm_runtime_put_autosuspend(up->dev);
700 static void serial_omap_break_ctl(struct uart_port *port, int break_state)
702 struct uart_omap_port *up = to_uart_omap_port(port);
703 unsigned long flags = 0;
705 dev_dbg(up->port.dev, "serial_omap_break_ctl+%d\n", up->port.line);
706 pm_runtime_get_sync(up->dev);
707 spin_lock_irqsave(&up->port.lock, flags);
708 if (break_state == -1)
709 up->lcr |= UART_LCR_SBC;
710 else
711 up->lcr &= ~UART_LCR_SBC;
712 serial_out(up, UART_LCR, up->lcr);
713 spin_unlock_irqrestore(&up->port.lock, flags);
714 pm_runtime_mark_last_busy(up->dev);
715 pm_runtime_put_autosuspend(up->dev);
718 static int serial_omap_startup(struct uart_port *port)
720 struct uart_omap_port *up = to_uart_omap_port(port);
721 unsigned long flags = 0;
722 int retval;
725 * Allocate the IRQ
727 retval = request_irq(up->port.irq, serial_omap_irq, up->port.irqflags,
728 up->name, up);
729 if (retval)
730 return retval;
732 /* Optional wake-up IRQ */
733 if (up->wakeirq) {
734 retval = dev_pm_set_dedicated_wake_irq(up->dev, up->wakeirq);
735 if (retval) {
736 free_irq(up->port.irq, up);
737 return retval;
741 dev_dbg(up->port.dev, "serial_omap_startup+%d\n", up->port.line);
743 pm_runtime_get_sync(up->dev);
745 * Clear the FIFO buffers and disable them.
746 * (they will be reenabled in set_termios())
748 serial_omap_clear_fifos(up);
751 * Clear the interrupt registers.
753 (void) serial_in(up, UART_LSR);
754 if (serial_in(up, UART_LSR) & UART_LSR_DR)
755 (void) serial_in(up, UART_RX);
756 (void) serial_in(up, UART_IIR);
757 (void) serial_in(up, UART_MSR);
760 * Now, initialize the UART
762 serial_out(up, UART_LCR, UART_LCR_WLEN8);
763 spin_lock_irqsave(&up->port.lock, flags);
765 * Most PC uarts need OUT2 raised to enable interrupts.
767 up->port.mctrl |= TIOCM_OUT2;
768 serial_omap_set_mctrl(&up->port, up->port.mctrl);
769 spin_unlock_irqrestore(&up->port.lock, flags);
771 up->msr_saved_flags = 0;
773 * Finally, enable interrupts. Note: Modem status interrupts
774 * are set via set_termios(), which will be occurring imminently
775 * anyway, so we don't enable them here.
777 up->ier = UART_IER_RLSI | UART_IER_RDI;
778 serial_out(up, UART_IER, up->ier);
780 /* Enable module level wake up */
781 up->wer = OMAP_UART_WER_MOD_WKUP;
782 if (up->features & OMAP_UART_WER_HAS_TX_WAKEUP)
783 up->wer |= OMAP_UART_TX_WAKEUP_EN;
785 serial_out(up, UART_OMAP_WER, up->wer);
787 pm_runtime_mark_last_busy(up->dev);
788 pm_runtime_put_autosuspend(up->dev);
789 up->port_activity = jiffies;
790 return 0;
793 static void serial_omap_shutdown(struct uart_port *port)
795 struct uart_omap_port *up = to_uart_omap_port(port);
796 unsigned long flags = 0;
798 dev_dbg(up->port.dev, "serial_omap_shutdown+%d\n", up->port.line);
800 pm_runtime_get_sync(up->dev);
802 * Disable interrupts from this port
804 up->ier = 0;
805 serial_out(up, UART_IER, 0);
807 spin_lock_irqsave(&up->port.lock, flags);
808 up->port.mctrl &= ~TIOCM_OUT2;
809 serial_omap_set_mctrl(&up->port, up->port.mctrl);
810 spin_unlock_irqrestore(&up->port.lock, flags);
813 * Disable break condition and FIFOs
815 serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
816 serial_omap_clear_fifos(up);
819 * Read data port to reset things, and then free the irq
821 if (serial_in(up, UART_LSR) & UART_LSR_DR)
822 (void) serial_in(up, UART_RX);
824 pm_runtime_mark_last_busy(up->dev);
825 pm_runtime_put_autosuspend(up->dev);
826 free_irq(up->port.irq, up);
827 dev_pm_clear_wake_irq(up->dev);
830 static void serial_omap_uart_qos_work(struct work_struct *work)
832 struct uart_omap_port *up = container_of(work, struct uart_omap_port,
833 qos_work);
835 pm_qos_update_request(&up->pm_qos_request, up->latency);
838 static void
839 serial_omap_set_termios(struct uart_port *port, struct ktermios *termios,
840 struct ktermios *old)
842 struct uart_omap_port *up = to_uart_omap_port(port);
843 unsigned char cval = 0;
844 unsigned long flags = 0;
845 unsigned int baud, quot;
847 switch (termios->c_cflag & CSIZE) {
848 case CS5:
849 cval = UART_LCR_WLEN5;
850 break;
851 case CS6:
852 cval = UART_LCR_WLEN6;
853 break;
854 case CS7:
855 cval = UART_LCR_WLEN7;
856 break;
857 default:
858 case CS8:
859 cval = UART_LCR_WLEN8;
860 break;
863 if (termios->c_cflag & CSTOPB)
864 cval |= UART_LCR_STOP;
865 if (termios->c_cflag & PARENB)
866 cval |= UART_LCR_PARITY;
867 if (!(termios->c_cflag & PARODD))
868 cval |= UART_LCR_EPAR;
869 if (termios->c_cflag & CMSPAR)
870 cval |= UART_LCR_SPAR;
873 * Ask the core to calculate the divisor for us.
876 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/13);
877 quot = serial_omap_get_divisor(port, baud);
879 /* calculate wakeup latency constraint */
880 up->calc_latency = (USEC_PER_SEC * up->port.fifosize) / (baud / 8);
881 up->latency = up->calc_latency;
882 schedule_work(&up->qos_work);
884 up->dll = quot & 0xff;
885 up->dlh = quot >> 8;
886 up->mdr1 = UART_OMAP_MDR1_DISABLE;
888 up->fcr = UART_FCR_R_TRIG_01 | UART_FCR_T_TRIG_01 |
889 UART_FCR_ENABLE_FIFO;
892 * Ok, we're now changing the port state. Do it with
893 * interrupts disabled.
895 pm_runtime_get_sync(up->dev);
896 spin_lock_irqsave(&up->port.lock, flags);
899 * Update the per-port timeout.
901 uart_update_timeout(port, termios->c_cflag, baud);
903 up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
904 if (termios->c_iflag & INPCK)
905 up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
906 if (termios->c_iflag & (BRKINT | PARMRK))
907 up->port.read_status_mask |= UART_LSR_BI;
910 * Characters to ignore
912 up->port.ignore_status_mask = 0;
913 if (termios->c_iflag & IGNPAR)
914 up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
915 if (termios->c_iflag & IGNBRK) {
916 up->port.ignore_status_mask |= UART_LSR_BI;
918 * If we're ignoring parity and break indicators,
919 * ignore overruns too (for real raw support).
921 if (termios->c_iflag & IGNPAR)
922 up->port.ignore_status_mask |= UART_LSR_OE;
926 * ignore all characters if CREAD is not set
928 if ((termios->c_cflag & CREAD) == 0)
929 up->port.ignore_status_mask |= UART_LSR_DR;
932 * Modem status interrupts
934 up->ier &= ~UART_IER_MSI;
935 if (UART_ENABLE_MS(&up->port, termios->c_cflag))
936 up->ier |= UART_IER_MSI;
937 serial_out(up, UART_IER, up->ier);
938 serial_out(up, UART_LCR, cval); /* reset DLAB */
939 up->lcr = cval;
940 up->scr = 0;
942 /* FIFOs and DMA Settings */
944 /* FCR can be changed only when the
945 * baud clock is not running
946 * DLL_REG and DLH_REG set to 0.
948 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
949 serial_out(up, UART_DLL, 0);
950 serial_out(up, UART_DLM, 0);
951 serial_out(up, UART_LCR, 0);
953 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
955 up->efr = serial_in(up, UART_EFR) & ~UART_EFR_ECB;
956 up->efr &= ~UART_EFR_SCD;
957 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
959 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
960 up->mcr = serial_in(up, UART_MCR) & ~UART_MCR_TCRTLR;
961 serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
962 /* FIFO ENABLE, DMA MODE */
964 up->scr |= OMAP_UART_SCR_RX_TRIG_GRANU1_MASK;
966 * NOTE: Setting OMAP_UART_SCR_RX_TRIG_GRANU1_MASK
967 * sets Enables the granularity of 1 for TRIGGER RX
968 * level. Along with setting RX FIFO trigger level
969 * to 1 (as noted below, 16 characters) and TLR[3:0]
970 * to zero this will result RX FIFO threshold level
971 * to 1 character, instead of 16 as noted in comment
972 * below.
975 /* Set receive FIFO threshold to 16 characters and
976 * transmit FIFO threshold to 32 spaces
978 up->fcr &= ~OMAP_UART_FCR_RX_FIFO_TRIG_MASK;
979 up->fcr &= ~OMAP_UART_FCR_TX_FIFO_TRIG_MASK;
980 up->fcr |= UART_FCR6_R_TRIGGER_16 | UART_FCR6_T_TRIGGER_24 |
981 UART_FCR_ENABLE_FIFO;
983 serial_out(up, UART_FCR, up->fcr);
984 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
986 serial_out(up, UART_OMAP_SCR, up->scr);
988 /* Reset UART_MCR_TCRTLR: this must be done with the EFR_ECB bit set */
989 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
990 serial_out(up, UART_MCR, up->mcr);
991 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
992 serial_out(up, UART_EFR, up->efr);
993 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
995 /* Protocol, Baud Rate, and Interrupt Settings */
997 if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
998 serial_omap_mdr1_errataset(up, up->mdr1);
999 else
1000 serial_out(up, UART_OMAP_MDR1, up->mdr1);
1002 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1003 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1005 serial_out(up, UART_LCR, 0);
1006 serial_out(up, UART_IER, 0);
1007 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1009 serial_out(up, UART_DLL, up->dll); /* LS of divisor */
1010 serial_out(up, UART_DLM, up->dlh); /* MS of divisor */
1012 serial_out(up, UART_LCR, 0);
1013 serial_out(up, UART_IER, up->ier);
1014 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1016 serial_out(up, UART_EFR, up->efr);
1017 serial_out(up, UART_LCR, cval);
1019 if (!serial_omap_baud_is_mode16(port, baud))
1020 up->mdr1 = UART_OMAP_MDR1_13X_MODE;
1021 else
1022 up->mdr1 = UART_OMAP_MDR1_16X_MODE;
1024 if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1025 serial_omap_mdr1_errataset(up, up->mdr1);
1026 else
1027 serial_out(up, UART_OMAP_MDR1, up->mdr1);
1029 /* Configure flow control */
1030 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1032 /* XON1/XOFF1 accessible mode B, TCRTLR=0, ECB=0 */
1033 serial_out(up, UART_XON1, termios->c_cc[VSTART]);
1034 serial_out(up, UART_XOFF1, termios->c_cc[VSTOP]);
1036 /* Enable access to TCR/TLR */
1037 serial_out(up, UART_EFR, up->efr | UART_EFR_ECB);
1038 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1039 serial_out(up, UART_MCR, up->mcr | UART_MCR_TCRTLR);
1041 serial_out(up, UART_TI752_TCR, OMAP_UART_TCR_TRIG);
1043 up->port.status &= ~(UPSTAT_AUTOCTS | UPSTAT_AUTORTS | UPSTAT_AUTOXOFF);
1045 if (termios->c_cflag & CRTSCTS && up->port.flags & UPF_HARD_FLOW) {
1046 /* Enable AUTOCTS (autoRTS is enabled when RTS is raised) */
1047 up->port.status |= UPSTAT_AUTOCTS | UPSTAT_AUTORTS;
1048 up->efr |= UART_EFR_CTS;
1049 } else {
1050 /* Disable AUTORTS and AUTOCTS */
1051 up->efr &= ~(UART_EFR_CTS | UART_EFR_RTS);
1054 if (up->port.flags & UPF_SOFT_FLOW) {
1055 /* clear SW control mode bits */
1056 up->efr &= OMAP_UART_SW_CLR;
1059 * IXON Flag:
1060 * Enable XON/XOFF flow control on input.
1061 * Receiver compares XON1, XOFF1.
1063 if (termios->c_iflag & IXON)
1064 up->efr |= OMAP_UART_SW_RX;
1067 * IXOFF Flag:
1068 * Enable XON/XOFF flow control on output.
1069 * Transmit XON1, XOFF1
1071 if (termios->c_iflag & IXOFF) {
1072 up->port.status |= UPSTAT_AUTOXOFF;
1073 up->efr |= OMAP_UART_SW_TX;
1077 * IXANY Flag:
1078 * Enable any character to restart output.
1079 * Operation resumes after receiving any
1080 * character after recognition of the XOFF character
1082 if (termios->c_iflag & IXANY)
1083 up->mcr |= UART_MCR_XONANY;
1084 else
1085 up->mcr &= ~UART_MCR_XONANY;
1087 serial_out(up, UART_MCR, up->mcr);
1088 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1089 serial_out(up, UART_EFR, up->efr);
1090 serial_out(up, UART_LCR, up->lcr);
1092 serial_omap_set_mctrl(&up->port, up->port.mctrl);
1094 spin_unlock_irqrestore(&up->port.lock, flags);
1095 pm_runtime_mark_last_busy(up->dev);
1096 pm_runtime_put_autosuspend(up->dev);
1097 dev_dbg(up->port.dev, "serial_omap_set_termios+%d\n", up->port.line);
1100 static void
1101 serial_omap_pm(struct uart_port *port, unsigned int state,
1102 unsigned int oldstate)
1104 struct uart_omap_port *up = to_uart_omap_port(port);
1105 unsigned char efr;
1107 dev_dbg(up->port.dev, "serial_omap_pm+%d\n", up->port.line);
1109 pm_runtime_get_sync(up->dev);
1110 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1111 efr = serial_in(up, UART_EFR);
1112 serial_out(up, UART_EFR, efr | UART_EFR_ECB);
1113 serial_out(up, UART_LCR, 0);
1115 serial_out(up, UART_IER, (state != 0) ? UART_IERX_SLEEP : 0);
1116 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B);
1117 serial_out(up, UART_EFR, efr);
1118 serial_out(up, UART_LCR, 0);
1120 pm_runtime_mark_last_busy(up->dev);
1121 pm_runtime_put_autosuspend(up->dev);
1124 static void serial_omap_release_port(struct uart_port *port)
1126 dev_dbg(port->dev, "serial_omap_release_port+\n");
1129 static int serial_omap_request_port(struct uart_port *port)
1131 dev_dbg(port->dev, "serial_omap_request_port+\n");
1132 return 0;
1135 static void serial_omap_config_port(struct uart_port *port, int flags)
1137 struct uart_omap_port *up = to_uart_omap_port(port);
1139 dev_dbg(up->port.dev, "serial_omap_config_port+%d\n",
1140 up->port.line);
1141 up->port.type = PORT_OMAP;
1142 up->port.flags |= UPF_SOFT_FLOW | UPF_HARD_FLOW;
1145 static int
1146 serial_omap_verify_port(struct uart_port *port, struct serial_struct *ser)
1148 /* we don't want the core code to modify any port params */
1149 dev_dbg(port->dev, "serial_omap_verify_port+\n");
1150 return -EINVAL;
1153 static const char *
1154 serial_omap_type(struct uart_port *port)
1156 struct uart_omap_port *up = to_uart_omap_port(port);
1158 dev_dbg(up->port.dev, "serial_omap_type+%d\n", up->port.line);
1159 return up->name;
1162 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1164 static void __maybe_unused wait_for_xmitr(struct uart_omap_port *up)
1166 unsigned int status, tmout = 10000;
1168 /* Wait up to 10ms for the character(s) to be sent. */
1169 do {
1170 status = serial_in(up, UART_LSR);
1172 if (status & UART_LSR_BI)
1173 up->lsr_break_flag = UART_LSR_BI;
1175 if (--tmout == 0)
1176 break;
1177 udelay(1);
1178 } while ((status & BOTH_EMPTY) != BOTH_EMPTY);
1180 /* Wait up to 1s for flow control if necessary */
1181 if (up->port.flags & UPF_CONS_FLOW) {
1182 tmout = 1000000;
1183 for (tmout = 1000000; tmout; tmout--) {
1184 unsigned int msr = serial_in(up, UART_MSR);
1186 up->msr_saved_flags |= msr & MSR_SAVE_FLAGS;
1187 if (msr & UART_MSR_CTS)
1188 break;
1190 udelay(1);
1195 #ifdef CONFIG_CONSOLE_POLL
1197 static void serial_omap_poll_put_char(struct uart_port *port, unsigned char ch)
1199 struct uart_omap_port *up = to_uart_omap_port(port);
1201 pm_runtime_get_sync(up->dev);
1202 wait_for_xmitr(up);
1203 serial_out(up, UART_TX, ch);
1204 pm_runtime_mark_last_busy(up->dev);
1205 pm_runtime_put_autosuspend(up->dev);
1208 static int serial_omap_poll_get_char(struct uart_port *port)
1210 struct uart_omap_port *up = to_uart_omap_port(port);
1211 unsigned int status;
1213 pm_runtime_get_sync(up->dev);
1214 status = serial_in(up, UART_LSR);
1215 if (!(status & UART_LSR_DR)) {
1216 status = NO_POLL_CHAR;
1217 goto out;
1220 status = serial_in(up, UART_RX);
1222 out:
1223 pm_runtime_mark_last_busy(up->dev);
1224 pm_runtime_put_autosuspend(up->dev);
1226 return status;
1229 #endif /* CONFIG_CONSOLE_POLL */
1231 #ifdef CONFIG_SERIAL_OMAP_CONSOLE
1233 #ifdef CONFIG_SERIAL_EARLYCON
1234 static unsigned int omap_serial_early_in(struct uart_port *port, int offset)
1236 offset <<= port->regshift;
1237 return readw(port->membase + offset);
1240 static void omap_serial_early_out(struct uart_port *port, int offset,
1241 int value)
1243 offset <<= port->regshift;
1244 writew(value, port->membase + offset);
1247 static void omap_serial_early_putc(struct uart_port *port, int c)
1249 unsigned int status;
1251 for (;;) {
1252 status = omap_serial_early_in(port, UART_LSR);
1253 if ((status & BOTH_EMPTY) == BOTH_EMPTY)
1254 break;
1255 cpu_relax();
1257 omap_serial_early_out(port, UART_TX, c);
1260 static void early_omap_serial_write(struct console *console, const char *s,
1261 unsigned int count)
1263 struct earlycon_device *device = console->data;
1264 struct uart_port *port = &device->port;
1266 uart_console_write(port, s, count, omap_serial_early_putc);
1269 static int __init early_omap_serial_setup(struct earlycon_device *device,
1270 const char *options)
1272 struct uart_port *port = &device->port;
1274 if (!(device->port.membase || device->port.iobase))
1275 return -ENODEV;
1277 port->regshift = 2;
1278 device->con->write = early_omap_serial_write;
1279 return 0;
1282 OF_EARLYCON_DECLARE(omapserial, "ti,omap2-uart", early_omap_serial_setup);
1283 OF_EARLYCON_DECLARE(omapserial, "ti,omap3-uart", early_omap_serial_setup);
1284 OF_EARLYCON_DECLARE(omapserial, "ti,omap4-uart", early_omap_serial_setup);
1285 #endif /* CONFIG_SERIAL_EARLYCON */
1287 static struct uart_omap_port *serial_omap_console_ports[OMAP_MAX_HSUART_PORTS];
1289 static struct uart_driver serial_omap_reg;
1291 static void serial_omap_console_putchar(struct uart_port *port, int ch)
1293 struct uart_omap_port *up = to_uart_omap_port(port);
1295 wait_for_xmitr(up);
1296 serial_out(up, UART_TX, ch);
1299 static void
1300 serial_omap_console_write(struct console *co, const char *s,
1301 unsigned int count)
1303 struct uart_omap_port *up = serial_omap_console_ports[co->index];
1304 unsigned long flags;
1305 unsigned int ier;
1306 int locked = 1;
1308 pm_runtime_get_sync(up->dev);
1310 local_irq_save(flags);
1311 if (up->port.sysrq)
1312 locked = 0;
1313 else if (oops_in_progress)
1314 locked = spin_trylock(&up->port.lock);
1315 else
1316 spin_lock(&up->port.lock);
1319 * First save the IER then disable the interrupts
1321 ier = serial_in(up, UART_IER);
1322 serial_out(up, UART_IER, 0);
1324 uart_console_write(&up->port, s, count, serial_omap_console_putchar);
1327 * Finally, wait for transmitter to become empty
1328 * and restore the IER
1330 wait_for_xmitr(up);
1331 serial_out(up, UART_IER, ier);
1333 * The receive handling will happen properly because the
1334 * receive ready bit will still be set; it is not cleared
1335 * on read. However, modem control will not, we must
1336 * call it if we have saved something in the saved flags
1337 * while processing with interrupts off.
1339 if (up->msr_saved_flags)
1340 check_modem_status(up);
1342 pm_runtime_mark_last_busy(up->dev);
1343 pm_runtime_put_autosuspend(up->dev);
1344 if (locked)
1345 spin_unlock(&up->port.lock);
1346 local_irq_restore(flags);
1349 static int __init
1350 serial_omap_console_setup(struct console *co, char *options)
1352 struct uart_omap_port *up;
1353 int baud = 115200;
1354 int bits = 8;
1355 int parity = 'n';
1356 int flow = 'n';
1358 if (serial_omap_console_ports[co->index] == NULL)
1359 return -ENODEV;
1360 up = serial_omap_console_ports[co->index];
1362 if (options)
1363 uart_parse_options(options, &baud, &parity, &bits, &flow);
1365 return uart_set_options(&up->port, co, baud, parity, bits, flow);
1368 static struct console serial_omap_console = {
1369 .name = OMAP_SERIAL_NAME,
1370 .write = serial_omap_console_write,
1371 .device = uart_console_device,
1372 .setup = serial_omap_console_setup,
1373 .flags = CON_PRINTBUFFER,
1374 .index = -1,
1375 .data = &serial_omap_reg,
1378 static void serial_omap_add_console_port(struct uart_omap_port *up)
1380 serial_omap_console_ports[up->port.line] = up;
1383 #define OMAP_CONSOLE (&serial_omap_console)
1385 #else
1387 #define OMAP_CONSOLE NULL
1389 static inline void serial_omap_add_console_port(struct uart_omap_port *up)
1392 #endif
1394 /* Enable or disable the rs485 support */
1395 static int
1396 serial_omap_config_rs485(struct uart_port *port, struct serial_rs485 *rs485)
1398 struct uart_omap_port *up = to_uart_omap_port(port);
1399 unsigned int mode;
1400 int val;
1402 pm_runtime_get_sync(up->dev);
1404 /* Disable interrupts from this port */
1405 mode = up->ier;
1406 up->ier = 0;
1407 serial_out(up, UART_IER, 0);
1409 /* Clamp the delays to [0, 100ms] */
1410 rs485->delay_rts_before_send = min(rs485->delay_rts_before_send, 100U);
1411 rs485->delay_rts_after_send = min(rs485->delay_rts_after_send, 100U);
1413 /* store new config */
1414 port->rs485 = *rs485;
1417 * Just as a precaution, only allow rs485
1418 * to be enabled if the gpio pin is valid
1420 if (gpio_is_valid(up->rts_gpio)) {
1421 /* enable / disable rts */
1422 val = (port->rs485.flags & SER_RS485_ENABLED) ?
1423 SER_RS485_RTS_AFTER_SEND : SER_RS485_RTS_ON_SEND;
1424 val = (port->rs485.flags & val) ? 1 : 0;
1425 gpio_set_value(up->rts_gpio, val);
1426 } else
1427 port->rs485.flags &= ~SER_RS485_ENABLED;
1429 /* Enable interrupts */
1430 up->ier = mode;
1431 serial_out(up, UART_IER, up->ier);
1433 /* If RS-485 is disabled, make sure the THR interrupt is fired when
1434 * TX FIFO is below the trigger level.
1436 if (!(port->rs485.flags & SER_RS485_ENABLED) &&
1437 (up->scr & OMAP_UART_SCR_TX_EMPTY)) {
1438 up->scr &= ~OMAP_UART_SCR_TX_EMPTY;
1439 serial_out(up, UART_OMAP_SCR, up->scr);
1442 pm_runtime_mark_last_busy(up->dev);
1443 pm_runtime_put_autosuspend(up->dev);
1445 return 0;
1448 static const struct uart_ops serial_omap_pops = {
1449 .tx_empty = serial_omap_tx_empty,
1450 .set_mctrl = serial_omap_set_mctrl,
1451 .get_mctrl = serial_omap_get_mctrl,
1452 .stop_tx = serial_omap_stop_tx,
1453 .start_tx = serial_omap_start_tx,
1454 .throttle = serial_omap_throttle,
1455 .unthrottle = serial_omap_unthrottle,
1456 .stop_rx = serial_omap_stop_rx,
1457 .enable_ms = serial_omap_enable_ms,
1458 .break_ctl = serial_omap_break_ctl,
1459 .startup = serial_omap_startup,
1460 .shutdown = serial_omap_shutdown,
1461 .set_termios = serial_omap_set_termios,
1462 .pm = serial_omap_pm,
1463 .type = serial_omap_type,
1464 .release_port = serial_omap_release_port,
1465 .request_port = serial_omap_request_port,
1466 .config_port = serial_omap_config_port,
1467 .verify_port = serial_omap_verify_port,
1468 #ifdef CONFIG_CONSOLE_POLL
1469 .poll_put_char = serial_omap_poll_put_char,
1470 .poll_get_char = serial_omap_poll_get_char,
1471 #endif
1474 static struct uart_driver serial_omap_reg = {
1475 .owner = THIS_MODULE,
1476 .driver_name = "OMAP-SERIAL",
1477 .dev_name = OMAP_SERIAL_NAME,
1478 .nr = OMAP_MAX_HSUART_PORTS,
1479 .cons = OMAP_CONSOLE,
1482 #ifdef CONFIG_PM_SLEEP
1483 static int serial_omap_prepare(struct device *dev)
1485 struct uart_omap_port *up = dev_get_drvdata(dev);
1487 up->is_suspending = true;
1489 return 0;
1492 static void serial_omap_complete(struct device *dev)
1494 struct uart_omap_port *up = dev_get_drvdata(dev);
1496 up->is_suspending = false;
1499 static int serial_omap_suspend(struct device *dev)
1501 struct uart_omap_port *up = dev_get_drvdata(dev);
1503 uart_suspend_port(&serial_omap_reg, &up->port);
1504 flush_work(&up->qos_work);
1506 if (device_may_wakeup(dev))
1507 serial_omap_enable_wakeup(up, true);
1508 else
1509 serial_omap_enable_wakeup(up, false);
1511 return 0;
1514 static int serial_omap_resume(struct device *dev)
1516 struct uart_omap_port *up = dev_get_drvdata(dev);
1518 if (device_may_wakeup(dev))
1519 serial_omap_enable_wakeup(up, false);
1521 uart_resume_port(&serial_omap_reg, &up->port);
1523 return 0;
1525 #else
1526 #define serial_omap_prepare NULL
1527 #define serial_omap_complete NULL
1528 #endif /* CONFIG_PM_SLEEP */
1530 static void omap_serial_fill_features_erratas(struct uart_omap_port *up)
1532 u32 mvr, scheme;
1533 u16 revision, major, minor;
1535 mvr = readl(up->port.membase + (UART_OMAP_MVER << up->port.regshift));
1537 /* Check revision register scheme */
1538 scheme = mvr >> OMAP_UART_MVR_SCHEME_SHIFT;
1540 switch (scheme) {
1541 case 0: /* Legacy Scheme: OMAP2/3 */
1542 /* MINOR_REV[0:4], MAJOR_REV[4:7] */
1543 major = (mvr & OMAP_UART_LEGACY_MVR_MAJ_MASK) >>
1544 OMAP_UART_LEGACY_MVR_MAJ_SHIFT;
1545 minor = (mvr & OMAP_UART_LEGACY_MVR_MIN_MASK);
1546 break;
1547 case 1:
1548 /* New Scheme: OMAP4+ */
1549 /* MINOR_REV[0:5], MAJOR_REV[8:10] */
1550 major = (mvr & OMAP_UART_MVR_MAJ_MASK) >>
1551 OMAP_UART_MVR_MAJ_SHIFT;
1552 minor = (mvr & OMAP_UART_MVR_MIN_MASK);
1553 break;
1554 default:
1555 dev_warn(up->dev,
1556 "Unknown %s revision, defaulting to highest\n",
1557 up->name);
1558 /* highest possible revision */
1559 major = 0xff;
1560 minor = 0xff;
1563 /* normalize revision for the driver */
1564 revision = UART_BUILD_REVISION(major, minor);
1566 switch (revision) {
1567 case OMAP_UART_REV_46:
1568 up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1569 UART_ERRATA_i291_DMA_FORCEIDLE);
1570 break;
1571 case OMAP_UART_REV_52:
1572 up->errata |= (UART_ERRATA_i202_MDR1_ACCESS |
1573 UART_ERRATA_i291_DMA_FORCEIDLE);
1574 up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1575 break;
1576 case OMAP_UART_REV_63:
1577 up->errata |= UART_ERRATA_i202_MDR1_ACCESS;
1578 up->features |= OMAP_UART_WER_HAS_TX_WAKEUP;
1579 break;
1580 default:
1581 break;
1585 static struct omap_uart_port_info *of_get_uart_port_info(struct device *dev)
1587 struct omap_uart_port_info *omap_up_info;
1589 omap_up_info = devm_kzalloc(dev, sizeof(*omap_up_info), GFP_KERNEL);
1590 if (!omap_up_info)
1591 return NULL; /* out of memory */
1593 of_property_read_u32(dev->of_node, "clock-frequency",
1594 &omap_up_info->uartclk);
1596 omap_up_info->flags = UPF_BOOT_AUTOCONF;
1598 return omap_up_info;
1601 static int serial_omap_probe_rs485(struct uart_omap_port *up,
1602 struct device_node *np)
1604 struct serial_rs485 *rs485conf = &up->port.rs485;
1605 int ret;
1607 rs485conf->flags = 0;
1608 up->rts_gpio = -EINVAL;
1610 if (!np)
1611 return 0;
1613 uart_get_rs485_mode(up->dev, rs485conf);
1615 if (of_property_read_bool(np, "rs485-rts-active-high")) {
1616 rs485conf->flags |= SER_RS485_RTS_ON_SEND;
1617 rs485conf->flags &= ~SER_RS485_RTS_AFTER_SEND;
1618 } else {
1619 rs485conf->flags &= ~SER_RS485_RTS_ON_SEND;
1620 rs485conf->flags |= SER_RS485_RTS_AFTER_SEND;
1623 /* check for tx enable gpio */
1624 up->rts_gpio = of_get_named_gpio(np, "rts-gpio", 0);
1625 if (gpio_is_valid(up->rts_gpio)) {
1626 ret = devm_gpio_request(up->dev, up->rts_gpio, "omap-serial");
1627 if (ret < 0)
1628 return ret;
1629 ret = rs485conf->flags & SER_RS485_RTS_AFTER_SEND ? 1 : 0;
1630 ret = gpio_direction_output(up->rts_gpio, ret);
1631 if (ret < 0)
1632 return ret;
1633 } else if (up->rts_gpio == -EPROBE_DEFER) {
1634 return -EPROBE_DEFER;
1635 } else {
1636 up->rts_gpio = -EINVAL;
1639 return 0;
1642 static int serial_omap_probe(struct platform_device *pdev)
1644 struct omap_uart_port_info *omap_up_info = dev_get_platdata(&pdev->dev);
1645 struct uart_omap_port *up;
1646 struct resource *mem;
1647 void __iomem *base;
1648 int uartirq = 0;
1649 int wakeirq = 0;
1650 int ret;
1652 /* The optional wakeirq may be specified in the board dts file */
1653 if (pdev->dev.of_node) {
1654 uartirq = irq_of_parse_and_map(pdev->dev.of_node, 0);
1655 if (!uartirq)
1656 return -EPROBE_DEFER;
1657 wakeirq = irq_of_parse_and_map(pdev->dev.of_node, 1);
1658 omap_up_info = of_get_uart_port_info(&pdev->dev);
1659 pdev->dev.platform_data = omap_up_info;
1660 } else {
1661 uartirq = platform_get_irq(pdev, 0);
1662 if (uartirq < 0)
1663 return -EPROBE_DEFER;
1666 up = devm_kzalloc(&pdev->dev, sizeof(*up), GFP_KERNEL);
1667 if (!up)
1668 return -ENOMEM;
1670 mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1671 base = devm_ioremap_resource(&pdev->dev, mem);
1672 if (IS_ERR(base))
1673 return PTR_ERR(base);
1675 up->dev = &pdev->dev;
1676 up->port.dev = &pdev->dev;
1677 up->port.type = PORT_OMAP;
1678 up->port.iotype = UPIO_MEM;
1679 up->port.irq = uartirq;
1680 up->port.regshift = 2;
1681 up->port.fifosize = 64;
1682 up->port.ops = &serial_omap_pops;
1684 if (pdev->dev.of_node)
1685 ret = of_alias_get_id(pdev->dev.of_node, "serial");
1686 else
1687 ret = pdev->id;
1689 if (ret < 0) {
1690 dev_err(&pdev->dev, "failed to get alias/pdev id, errno %d\n",
1691 ret);
1692 goto err_port_line;
1694 up->port.line = ret;
1696 if (up->port.line >= OMAP_MAX_HSUART_PORTS) {
1697 dev_err(&pdev->dev, "uart ID %d > MAX %d.\n", up->port.line,
1698 OMAP_MAX_HSUART_PORTS);
1699 ret = -ENXIO;
1700 goto err_port_line;
1703 up->wakeirq = wakeirq;
1704 if (!up->wakeirq)
1705 dev_info(up->port.dev, "no wakeirq for uart%d\n",
1706 up->port.line);
1708 ret = serial_omap_probe_rs485(up, pdev->dev.of_node);
1709 if (ret < 0)
1710 goto err_rs485;
1712 sprintf(up->name, "OMAP UART%d", up->port.line);
1713 up->port.mapbase = mem->start;
1714 up->port.membase = base;
1715 up->port.flags = omap_up_info->flags;
1716 up->port.uartclk = omap_up_info->uartclk;
1717 up->port.rs485_config = serial_omap_config_rs485;
1718 if (!up->port.uartclk) {
1719 up->port.uartclk = DEFAULT_CLK_SPEED;
1720 dev_warn(&pdev->dev,
1721 "No clock speed specified: using default: %d\n",
1722 DEFAULT_CLK_SPEED);
1725 up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1726 up->calc_latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1727 pm_qos_add_request(&up->pm_qos_request,
1728 PM_QOS_CPU_DMA_LATENCY, up->latency);
1729 INIT_WORK(&up->qos_work, serial_omap_uart_qos_work);
1731 platform_set_drvdata(pdev, up);
1732 if (omap_up_info->autosuspend_timeout == 0)
1733 omap_up_info->autosuspend_timeout = -1;
1735 device_init_wakeup(up->dev, true);
1736 pm_runtime_use_autosuspend(&pdev->dev);
1737 pm_runtime_set_autosuspend_delay(&pdev->dev,
1738 omap_up_info->autosuspend_timeout);
1740 pm_runtime_irq_safe(&pdev->dev);
1741 pm_runtime_enable(&pdev->dev);
1743 pm_runtime_get_sync(&pdev->dev);
1745 omap_serial_fill_features_erratas(up);
1747 ui[up->port.line] = up;
1748 serial_omap_add_console_port(up);
1750 ret = uart_add_one_port(&serial_omap_reg, &up->port);
1751 if (ret != 0)
1752 goto err_add_port;
1754 pm_runtime_mark_last_busy(up->dev);
1755 pm_runtime_put_autosuspend(up->dev);
1756 return 0;
1758 err_add_port:
1759 pm_runtime_dont_use_autosuspend(&pdev->dev);
1760 pm_runtime_put_sync(&pdev->dev);
1761 pm_runtime_disable(&pdev->dev);
1762 pm_qos_remove_request(&up->pm_qos_request);
1763 device_init_wakeup(up->dev, false);
1764 err_rs485:
1765 err_port_line:
1766 return ret;
1769 static int serial_omap_remove(struct platform_device *dev)
1771 struct uart_omap_port *up = platform_get_drvdata(dev);
1773 pm_runtime_get_sync(up->dev);
1775 uart_remove_one_port(&serial_omap_reg, &up->port);
1777 pm_runtime_dont_use_autosuspend(up->dev);
1778 pm_runtime_put_sync(up->dev);
1779 pm_runtime_disable(up->dev);
1780 pm_qos_remove_request(&up->pm_qos_request);
1781 device_init_wakeup(&dev->dev, false);
1783 return 0;
1787 * Work Around for Errata i202 (2430, 3430, 3630, 4430 and 4460)
1788 * The access to uart register after MDR1 Access
1789 * causes UART to corrupt data.
1791 * Need a delay =
1792 * 5 L4 clock cycles + 5 UART functional clock cycle (@48MHz = ~0.2uS)
1793 * give 10 times as much
1795 static void serial_omap_mdr1_errataset(struct uart_omap_port *up, u8 mdr1)
1797 u8 timeout = 255;
1799 serial_out(up, UART_OMAP_MDR1, mdr1);
1800 udelay(2);
1801 serial_out(up, UART_FCR, up->fcr | UART_FCR_CLEAR_XMIT |
1802 UART_FCR_CLEAR_RCVR);
1804 * Wait for FIFO to empty: when empty, RX_FIFO_E bit is 0 and
1805 * TX_FIFO_E bit is 1.
1807 while (UART_LSR_THRE != (serial_in(up, UART_LSR) &
1808 (UART_LSR_THRE | UART_LSR_DR))) {
1809 timeout--;
1810 if (!timeout) {
1811 /* Should *never* happen. we warn and carry on */
1812 dev_crit(up->dev, "Errata i202: timedout %x\n",
1813 serial_in(up, UART_LSR));
1814 break;
1816 udelay(1);
1820 #ifdef CONFIG_PM
1821 static void serial_omap_restore_context(struct uart_omap_port *up)
1823 if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1824 serial_omap_mdr1_errataset(up, UART_OMAP_MDR1_DISABLE);
1825 else
1826 serial_out(up, UART_OMAP_MDR1, UART_OMAP_MDR1_DISABLE);
1828 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1829 serial_out(up, UART_EFR, UART_EFR_ECB);
1830 serial_out(up, UART_LCR, 0x0); /* Operational mode */
1831 serial_out(up, UART_IER, 0x0);
1832 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1833 serial_out(up, UART_DLL, up->dll);
1834 serial_out(up, UART_DLM, up->dlh);
1835 serial_out(up, UART_LCR, 0x0); /* Operational mode */
1836 serial_out(up, UART_IER, up->ier);
1837 serial_out(up, UART_FCR, up->fcr);
1838 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_A);
1839 serial_out(up, UART_MCR, up->mcr);
1840 serial_out(up, UART_LCR, UART_LCR_CONF_MODE_B); /* Config B mode */
1841 serial_out(up, UART_OMAP_SCR, up->scr);
1842 serial_out(up, UART_EFR, up->efr);
1843 serial_out(up, UART_LCR, up->lcr);
1844 if (up->errata & UART_ERRATA_i202_MDR1_ACCESS)
1845 serial_omap_mdr1_errataset(up, up->mdr1);
1846 else
1847 serial_out(up, UART_OMAP_MDR1, up->mdr1);
1848 serial_out(up, UART_OMAP_WER, up->wer);
1851 static int serial_omap_runtime_suspend(struct device *dev)
1853 struct uart_omap_port *up = dev_get_drvdata(dev);
1855 if (!up)
1856 return -EINVAL;
1859 * When using 'no_console_suspend', the console UART must not be
1860 * suspended. Since driver suspend is managed by runtime suspend,
1861 * preventing runtime suspend (by returning error) will keep device
1862 * active during suspend.
1864 if (up->is_suspending && !console_suspend_enabled &&
1865 uart_console(&up->port))
1866 return -EBUSY;
1868 up->context_loss_cnt = serial_omap_get_context_loss_count(up);
1870 serial_omap_enable_wakeup(up, true);
1872 up->latency = PM_QOS_CPU_DMA_LAT_DEFAULT_VALUE;
1873 schedule_work(&up->qos_work);
1875 return 0;
1878 static int serial_omap_runtime_resume(struct device *dev)
1880 struct uart_omap_port *up = dev_get_drvdata(dev);
1882 int loss_cnt = serial_omap_get_context_loss_count(up);
1884 serial_omap_enable_wakeup(up, false);
1886 if (loss_cnt < 0) {
1887 dev_dbg(dev, "serial_omap_get_context_loss_count failed : %d\n",
1888 loss_cnt);
1889 serial_omap_restore_context(up);
1890 } else if (up->context_loss_cnt != loss_cnt) {
1891 serial_omap_restore_context(up);
1893 up->latency = up->calc_latency;
1894 schedule_work(&up->qos_work);
1896 return 0;
1898 #endif
1900 static const struct dev_pm_ops serial_omap_dev_pm_ops = {
1901 SET_SYSTEM_SLEEP_PM_OPS(serial_omap_suspend, serial_omap_resume)
1902 SET_RUNTIME_PM_OPS(serial_omap_runtime_suspend,
1903 serial_omap_runtime_resume, NULL)
1904 .prepare = serial_omap_prepare,
1905 .complete = serial_omap_complete,
1908 #if defined(CONFIG_OF)
1909 static const struct of_device_id omap_serial_of_match[] = {
1910 { .compatible = "ti,omap2-uart" },
1911 { .compatible = "ti,omap3-uart" },
1912 { .compatible = "ti,omap4-uart" },
1915 MODULE_DEVICE_TABLE(of, omap_serial_of_match);
1916 #endif
1918 static struct platform_driver serial_omap_driver = {
1919 .probe = serial_omap_probe,
1920 .remove = serial_omap_remove,
1921 .driver = {
1922 .name = OMAP_SERIAL_DRIVER_NAME,
1923 .pm = &serial_omap_dev_pm_ops,
1924 .of_match_table = of_match_ptr(omap_serial_of_match),
1928 static int __init serial_omap_init(void)
1930 int ret;
1932 ret = uart_register_driver(&serial_omap_reg);
1933 if (ret != 0)
1934 return ret;
1935 ret = platform_driver_register(&serial_omap_driver);
1936 if (ret != 0)
1937 uart_unregister_driver(&serial_omap_reg);
1938 return ret;
1941 static void __exit serial_omap_exit(void)
1943 platform_driver_unregister(&serial_omap_driver);
1944 uart_unregister_driver(&serial_omap_reg);
1947 module_init(serial_omap_init);
1948 module_exit(serial_omap_exit);
1950 MODULE_DESCRIPTION("OMAP High Speed UART driver");
1951 MODULE_LICENSE("GPL");
1952 MODULE_AUTHOR("Texas Instruments Inc");