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17#if defined(CONFIG_SERIAL_MSM_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
18# define SUPPORT_SYSRQ
19#endif
20
21#include <linux/hrtimer.h>
22#include <linux/module.h>
23#include <linux/io.h>
24#include <linux/ioport.h>
25#include <linux/irq.h>
26#include <linux/init.h>
27#include <linux/console.h>
28#include <linux/tty.h>
29#include <linux/tty_flip.h>
30#include <linux/serial_core.h>
31#include <linux/serial.h>
32#include <linux/clk.h>
33#include <linux/platform_device.h>
34
35#include "msm_serial.h"
36
37struct msm_port {
38 struct uart_port uart;
39 char name[16];
40 struct clk *clk;
41 unsigned int imr;
42};
43
44#define UART_TO_MSM(uart_port) ((struct msm_port *) uart_port)
45
46static inline void msm_write(struct uart_port *port, unsigned int val,
47 unsigned int off)
48{
49 __raw_writel(val, port->membase + off);
50}
51
52static inline unsigned int msm_read(struct uart_port *port, unsigned int off)
53{
54 return __raw_readl(port->membase + off);
55}
56
57static void msm_stop_tx(struct uart_port *port)
58{
59 struct msm_port *msm_port = UART_TO_MSM(port);
60
61 msm_port->imr &= ~UART_IMR_TXLEV;
62 msm_write(port, msm_port->imr, UART_IMR);
63}
64
65static void msm_start_tx(struct uart_port *port)
66{
67 struct msm_port *msm_port = UART_TO_MSM(port);
68
69 msm_port->imr |= UART_IMR_TXLEV;
70 msm_write(port, msm_port->imr, UART_IMR);
71}
72
73static void msm_stop_rx(struct uart_port *port)
74{
75 struct msm_port *msm_port = UART_TO_MSM(port);
76
77 msm_port->imr &= ~(UART_IMR_RXLEV | UART_IMR_RXSTALE);
78 msm_write(port, msm_port->imr, UART_IMR);
79}
80
81static void msm_enable_ms(struct uart_port *port)
82{
83 struct msm_port *msm_port = UART_TO_MSM(port);
84
85 msm_port->imr |= UART_IMR_DELTA_CTS;
86 msm_write(port, msm_port->imr, UART_IMR);
87}
88
89static void handle_rx(struct uart_port *port)
90{
91 struct tty_struct *tty = port->state->port.tty;
92 unsigned int sr;
93
94
95
96
97
98 if ((msm_read(port, UART_SR) & UART_SR_OVERRUN)) {
99 port->icount.overrun++;
100 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
101 msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
102 }
103
104
105 while ((sr = msm_read(port, UART_SR)) & UART_SR_RX_READY) {
106 unsigned int c;
107 char flag = TTY_NORMAL;
108
109 c = msm_read(port, UART_RF);
110
111 if (sr & UART_SR_RX_BREAK) {
112 port->icount.brk++;
113 if (uart_handle_break(port))
114 continue;
115 } else if (sr & UART_SR_PAR_FRAME_ERR) {
116 port->icount.frame++;
117 } else {
118 port->icount.rx++;
119 }
120
121
122 sr &= port->read_status_mask;
123
124 if (sr & UART_SR_RX_BREAK) {
125 flag = TTY_BREAK;
126 } else if (sr & UART_SR_PAR_FRAME_ERR) {
127 flag = TTY_FRAME;
128 }
129
130 if (!uart_handle_sysrq_char(port, c))
131 tty_insert_flip_char(tty, c, flag);
132 }
133
134 tty_flip_buffer_push(tty);
135}
136
137static void handle_tx(struct uart_port *port)
138{
139 struct circ_buf *xmit = &port->state->xmit;
140 struct msm_port *msm_port = UART_TO_MSM(port);
141 int sent_tx;
142
143 if (port->x_char) {
144 msm_write(port, port->x_char, UART_TF);
145 port->icount.tx++;
146 port->x_char = 0;
147 }
148
149 while (msm_read(port, UART_SR) & UART_SR_TX_READY) {
150 if (uart_circ_empty(xmit)) {
151
152 msm_port->imr &= ~UART_IMR_TXLEV;
153 msm_write(port, msm_port->imr, UART_IMR);
154 break;
155 }
156
157 msm_write(port, xmit->buf[xmit->tail], UART_TF);
158
159 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
160 port->icount.tx++;
161 sent_tx = 1;
162 }
163
164 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
165 uart_write_wakeup(port);
166}
167
168static void handle_delta_cts(struct uart_port *port)
169{
170 msm_write(port, UART_CR_CMD_RESET_CTS, UART_CR);
171 port->icount.cts++;
172 wake_up_interruptible(&port->state->port.delta_msr_wait);
173}
174
175static irqreturn_t msm_irq(int irq, void *dev_id)
176{
177 struct uart_port *port = dev_id;
178 struct msm_port *msm_port = UART_TO_MSM(port);
179 unsigned int misr;
180
181 spin_lock(&port->lock);
182 misr = msm_read(port, UART_MISR);
183 msm_write(port, 0, UART_IMR);
184
185 if (misr & (UART_IMR_RXLEV | UART_IMR_RXSTALE))
186 handle_rx(port);
187 if (misr & UART_IMR_TXLEV)
188 handle_tx(port);
189 if (misr & UART_IMR_DELTA_CTS)
190 handle_delta_cts(port);
191
192 msm_write(port, msm_port->imr, UART_IMR);
193 spin_unlock(&port->lock);
194
195 return IRQ_HANDLED;
196}
197
198static unsigned int msm_tx_empty(struct uart_port *port)
199{
200 return (msm_read(port, UART_SR) & UART_SR_TX_EMPTY) ? TIOCSER_TEMT : 0;
201}
202
203static unsigned int msm_get_mctrl(struct uart_port *port)
204{
205 return TIOCM_CAR | TIOCM_CTS | TIOCM_DSR | TIOCM_RTS;
206}
207
208static void msm_set_mctrl(struct uart_port *port, unsigned int mctrl)
209{
210 unsigned int mr;
211
212 mr = msm_read(port, UART_MR1);
213
214 if (!(mctrl & TIOCM_RTS)) {
215 mr &= ~UART_MR1_RX_RDY_CTL;
216 msm_write(port, mr, UART_MR1);
217 msm_write(port, UART_CR_CMD_RESET_RFR, UART_CR);
218 } else {
219 mr |= UART_MR1_RX_RDY_CTL;
220 msm_write(port, mr, UART_MR1);
221 }
222}
223
224static void msm_break_ctl(struct uart_port *port, int break_ctl)
225{
226 if (break_ctl)
227 msm_write(port, UART_CR_CMD_START_BREAK, UART_CR);
228 else
229 msm_write(port, UART_CR_CMD_STOP_BREAK, UART_CR);
230}
231
232static int msm_set_baud_rate(struct uart_port *port, unsigned int baud)
233{
234 unsigned int baud_code, rxstale, watermark;
235
236 switch (baud) {
237 case 300:
238 baud_code = UART_CSR_300;
239 rxstale = 1;
240 break;
241 case 600:
242 baud_code = UART_CSR_600;
243 rxstale = 1;
244 break;
245 case 1200:
246 baud_code = UART_CSR_1200;
247 rxstale = 1;
248 break;
249 case 2400:
250 baud_code = UART_CSR_2400;
251 rxstale = 1;
252 break;
253 case 4800:
254 baud_code = UART_CSR_4800;
255 rxstale = 1;
256 break;
257 case 9600:
258 baud_code = UART_CSR_9600;
259 rxstale = 2;
260 break;
261 case 14400:
262 baud_code = UART_CSR_14400;
263 rxstale = 3;
264 break;
265 case 19200:
266 baud_code = UART_CSR_19200;
267 rxstale = 4;
268 break;
269 case 28800:
270 baud_code = UART_CSR_28800;
271 rxstale = 6;
272 break;
273 case 38400:
274 baud_code = UART_CSR_38400;
275 rxstale = 8;
276 break;
277 case 57600:
278 baud_code = UART_CSR_57600;
279 rxstale = 16;
280 break;
281 case 115200:
282 default:
283 baud_code = UART_CSR_115200;
284 baud = 115200;
285 rxstale = 31;
286 break;
287 }
288
289 msm_write(port, baud_code, UART_CSR);
290
291
292 watermark = UART_IPR_STALE_LSB & rxstale;
293 watermark |= UART_IPR_RXSTALE_LAST;
294 watermark |= UART_IPR_STALE_TIMEOUT_MSB & (rxstale << 2);
295 msm_write(port, watermark, UART_IPR);
296
297
298 watermark = (port->fifosize * 3) / 4;
299 msm_write(port, watermark, UART_RFWR);
300
301
302 msm_write(port, 10, UART_TFWR);
303
304 return baud;
305}
306
307static void msm_reset(struct uart_port *port)
308{
309
310 msm_write(port, UART_CR_CMD_RESET_RX, UART_CR);
311 msm_write(port, UART_CR_CMD_RESET_TX, UART_CR);
312 msm_write(port, UART_CR_CMD_RESET_ERR, UART_CR);
313 msm_write(port, UART_CR_CMD_RESET_BREAK_INT, UART_CR);
314 msm_write(port, UART_CR_CMD_RESET_CTS, UART_CR);
315 msm_write(port, UART_CR_CMD_SET_RFR, UART_CR);
316}
317
318static void msm_init_clock(struct uart_port *port)
319{
320 struct msm_port *msm_port = UART_TO_MSM(port);
321
322 clk_enable(msm_port->clk);
323
324 msm_write(port, 0xC0, UART_MREG);
325 msm_write(port, 0xB2, UART_NREG);
326 msm_write(port, 0x7D, UART_DREG);
327 msm_write(port, 0x1C, UART_MNDREG);
328}
329
330static int msm_startup(struct uart_port *port)
331{
332 struct msm_port *msm_port = UART_TO_MSM(port);
333 unsigned int data, rfr_level;
334 int ret;
335
336 snprintf(msm_port->name, sizeof(msm_port->name),
337 "msm_serial%d", port->line);
338
339 ret = request_irq(port->irq, msm_irq, IRQF_TRIGGER_HIGH,
340 msm_port->name, port);
341 if (unlikely(ret))
342 return ret;
343
344 msm_init_clock(port);
345
346 if (likely(port->fifosize > 12))
347 rfr_level = port->fifosize - 12;
348 else
349 rfr_level = port->fifosize;
350
351
352 data = msm_read(port, UART_MR1);
353 data &= ~UART_MR1_AUTO_RFR_LEVEL1;
354 data &= ~UART_MR1_AUTO_RFR_LEVEL0;
355 data |= UART_MR1_AUTO_RFR_LEVEL1 & (rfr_level << 2);
356 data |= UART_MR1_AUTO_RFR_LEVEL0 & rfr_level;
357 msm_write(port, data, UART_MR1);
358
359
360 data = msm_read(port, UART_IPR);
361 if (unlikely(!data)) {
362 data |= UART_IPR_RXSTALE_LAST;
363 data |= UART_IPR_STALE_LSB;
364 msm_write(port, data, UART_IPR);
365 }
366
367 msm_reset(port);
368
369 msm_write(port, 0x05, UART_CR);
370
371
372 msm_port->imr = UART_IMR_RXLEV | UART_IMR_RXSTALE |
373 UART_IMR_CURRENT_CTS;
374 msm_write(port, msm_port->imr, UART_IMR);
375
376 return 0;
377}
378
379static void msm_shutdown(struct uart_port *port)
380{
381 struct msm_port *msm_port = UART_TO_MSM(port);
382
383 msm_port->imr = 0;
384 msm_write(port, 0, UART_IMR);
385
386 clk_disable(msm_port->clk);
387
388 free_irq(port->irq, port);
389}
390
391static void msm_set_termios(struct uart_port *port, struct ktermios *termios,
392 struct ktermios *old)
393{
394 unsigned long flags;
395 unsigned int baud, mr;
396
397 spin_lock_irqsave(&port->lock, flags);
398
399
400 baud = uart_get_baud_rate(port, termios, old, 300, 115200);
401 baud = msm_set_baud_rate(port, baud);
402 if (tty_termios_baud_rate(termios))
403 tty_termios_encode_baud_rate(termios, baud, baud);
404
405
406 mr = msm_read(port, UART_MR2);
407 mr &= ~UART_MR2_PARITY_MODE;
408 if (termios->c_cflag & PARENB) {
409 if (termios->c_cflag & PARODD)
410 mr |= UART_MR2_PARITY_MODE_ODD;
411 else if (termios->c_cflag & CMSPAR)
412 mr |= UART_MR2_PARITY_MODE_SPACE;
413 else
414 mr |= UART_MR2_PARITY_MODE_EVEN;
415 }
416
417
418 mr &= ~UART_MR2_BITS_PER_CHAR;
419 switch (termios->c_cflag & CSIZE) {
420 case CS5:
421 mr |= UART_MR2_BITS_PER_CHAR_5;
422 break;
423 case CS6:
424 mr |= UART_MR2_BITS_PER_CHAR_6;
425 break;
426 case CS7:
427 mr |= UART_MR2_BITS_PER_CHAR_7;
428 break;
429 case CS8:
430 default:
431 mr |= UART_MR2_BITS_PER_CHAR_8;
432 break;
433 }
434
435
436 mr &= ~(UART_MR2_STOP_BIT_LEN_ONE | UART_MR2_STOP_BIT_LEN_TWO);
437 if (termios->c_cflag & CSTOPB)
438 mr |= UART_MR2_STOP_BIT_LEN_TWO;
439 else
440 mr |= UART_MR2_STOP_BIT_LEN_ONE;
441
442
443 msm_write(port, mr, UART_MR2);
444
445
446 mr = msm_read(port, UART_MR1);
447 mr &= ~(UART_MR1_CTS_CTL | UART_MR1_RX_RDY_CTL);
448 if (termios->c_cflag & CRTSCTS) {
449 mr |= UART_MR1_CTS_CTL;
450 mr |= UART_MR1_RX_RDY_CTL;
451 }
452 msm_write(port, mr, UART_MR1);
453
454
455 port->read_status_mask = 0;
456 if (termios->c_iflag & INPCK)
457 port->read_status_mask |= UART_SR_PAR_FRAME_ERR;
458 if (termios->c_iflag & (BRKINT | PARMRK))
459 port->read_status_mask |= UART_SR_RX_BREAK;
460
461 uart_update_timeout(port, termios->c_cflag, baud);
462
463 spin_unlock_irqrestore(&port->lock, flags);
464}
465
466static const char *msm_type(struct uart_port *port)
467{
468 return "MSM";
469}
470
471static void msm_release_port(struct uart_port *port)
472{
473 struct platform_device *pdev = to_platform_device(port->dev);
474 struct resource *resource;
475 resource_size_t size;
476
477 resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
478 if (unlikely(!resource))
479 return;
480 size = resource->end - resource->start + 1;
481
482 release_mem_region(port->mapbase, size);
483 iounmap(port->membase);
484 port->membase = NULL;
485}
486
487static int msm_request_port(struct uart_port *port)
488{
489 struct platform_device *pdev = to_platform_device(port->dev);
490 struct resource *resource;
491 resource_size_t size;
492
493 resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
494 if (unlikely(!resource))
495 return -ENXIO;
496 size = resource->end - resource->start + 1;
497
498 if (unlikely(!request_mem_region(port->mapbase, size, "msm_serial")))
499 return -EBUSY;
500
501 port->membase = ioremap(port->mapbase, size);
502 if (!port->membase) {
503 release_mem_region(port->mapbase, size);
504 return -EBUSY;
505 }
506
507 return 0;
508}
509
510static void msm_config_port(struct uart_port *port, int flags)
511{
512 if (flags & UART_CONFIG_TYPE) {
513 port->type = PORT_MSM;
514 msm_request_port(port);
515 }
516}
517
518static int msm_verify_port(struct uart_port *port, struct serial_struct *ser)
519{
520 if (unlikely(ser->type != PORT_UNKNOWN && ser->type != PORT_MSM))
521 return -EINVAL;
522 if (unlikely(port->irq != ser->irq))
523 return -EINVAL;
524 return 0;
525}
526
527static void msm_power(struct uart_port *port, unsigned int state,
528 unsigned int oldstate)
529{
530 struct msm_port *msm_port = UART_TO_MSM(port);
531
532 switch (state) {
533 case 0:
534 clk_enable(msm_port->clk);
535 break;
536 case 3:
537 clk_disable(msm_port->clk);
538 break;
539 default:
540 printk(KERN_ERR "msm_serial: Unknown PM state %d\n", state);
541 }
542}
543
544static struct uart_ops msm_uart_pops = {
545 .tx_empty = msm_tx_empty,
546 .set_mctrl = msm_set_mctrl,
547 .get_mctrl = msm_get_mctrl,
548 .stop_tx = msm_stop_tx,
549 .start_tx = msm_start_tx,
550 .stop_rx = msm_stop_rx,
551 .enable_ms = msm_enable_ms,
552 .break_ctl = msm_break_ctl,
553 .startup = msm_startup,
554 .shutdown = msm_shutdown,
555 .set_termios = msm_set_termios,
556 .type = msm_type,
557 .release_port = msm_release_port,
558 .request_port = msm_request_port,
559 .config_port = msm_config_port,
560 .verify_port = msm_verify_port,
561 .pm = msm_power,
562};
563
564static struct msm_port msm_uart_ports[] = {
565 {
566 .uart = {
567 .iotype = UPIO_MEM,
568 .ops = &msm_uart_pops,
569 .flags = UPF_BOOT_AUTOCONF,
570 .fifosize = 512,
571 .line = 0,
572 },
573 },
574 {
575 .uart = {
576 .iotype = UPIO_MEM,
577 .ops = &msm_uart_pops,
578 .flags = UPF_BOOT_AUTOCONF,
579 .fifosize = 512,
580 .line = 1,
581 },
582 },
583 {
584 .uart = {
585 .iotype = UPIO_MEM,
586 .ops = &msm_uart_pops,
587 .flags = UPF_BOOT_AUTOCONF,
588 .fifosize = 64,
589 .line = 2,
590 },
591 },
592};
593
594#define UART_NR ARRAY_SIZE(msm_uart_ports)
595
596static inline struct uart_port *get_port_from_line(unsigned int line)
597{
598 return &msm_uart_ports[line].uart;
599}
600
601#ifdef CONFIG_SERIAL_MSM_CONSOLE
602
603static void msm_console_putchar(struct uart_port *port, int c)
604{
605 while (!(msm_read(port, UART_SR) & UART_SR_TX_READY))
606 ;
607 msm_write(port, c, UART_TF);
608}
609
610static void msm_console_write(struct console *co, const char *s,
611 unsigned int count)
612{
613 struct uart_port *port;
614 struct msm_port *msm_port;
615
616 BUG_ON(co->index < 0 || co->index >= UART_NR);
617
618 port = get_port_from_line(co->index);
619 msm_port = UART_TO_MSM(port);
620
621 spin_lock(&port->lock);
622 uart_console_write(port, s, count, msm_console_putchar);
623 spin_unlock(&port->lock);
624}
625
626static int __init msm_console_setup(struct console *co, char *options)
627{
628 struct uart_port *port;
629 int baud, flow, bits, parity;
630
631 if (unlikely(co->index >= UART_NR || co->index < 0))
632 return -ENXIO;
633
634 port = get_port_from_line(co->index);
635
636 if (unlikely(!port->membase))
637 return -ENXIO;
638
639 port->cons = co;
640
641 msm_init_clock(port);
642
643 if (options)
644 uart_parse_options(options, &baud, &parity, &bits, &flow);
645
646 bits = 8;
647 parity = 'n';
648 flow = 'n';
649 msm_write(port, UART_MR2_BITS_PER_CHAR_8 | UART_MR2_STOP_BIT_LEN_ONE,
650 UART_MR2);
651
652 if (baud < 300 || baud > 115200)
653 baud = 115200;
654 msm_set_baud_rate(port, baud);
655
656 msm_reset(port);
657
658 printk(KERN_INFO "msm_serial: console setup on port #%d\n", port->line);
659
660 return uart_set_options(port, co, baud, parity, bits, flow);
661}
662
663static struct uart_driver msm_uart_driver;
664
665static struct console msm_console = {
666 .name = "ttyMSM",
667 .write = msm_console_write,
668 .device = uart_console_device,
669 .setup = msm_console_setup,
670 .flags = CON_PRINTBUFFER,
671 .index = -1,
672 .data = &msm_uart_driver,
673};
674
675#define MSM_CONSOLE (&msm_console)
676
677#else
678#define MSM_CONSOLE NULL
679#endif
680
681static struct uart_driver msm_uart_driver = {
682 .owner = THIS_MODULE,
683 .driver_name = "msm_serial",
684 .dev_name = "ttyMSM",
685 .nr = UART_NR,
686 .cons = MSM_CONSOLE,
687};
688
689static int __init msm_serial_probe(struct platform_device *pdev)
690{
691 struct msm_port *msm_port;
692 struct resource *resource;
693 struct uart_port *port;
694
695 if (unlikely(pdev->id < 0 || pdev->id >= UART_NR))
696 return -ENXIO;
697
698 printk(KERN_INFO "msm_serial: detected port #%d\n", pdev->id);
699
700 port = get_port_from_line(pdev->id);
701 port->dev = &pdev->dev;
702 msm_port = UART_TO_MSM(port);
703
704 msm_port->clk = clk_get(&pdev->dev, "uart_clk");
705 if (unlikely(IS_ERR(msm_port->clk)))
706 return PTR_ERR(msm_port->clk);
707 port->uartclk = clk_get_rate(msm_port->clk);
708
709 resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
710 if (unlikely(!resource))
711 return -ENXIO;
712 port->mapbase = resource->start;
713
714 port->irq = platform_get_irq(pdev, 0);
715 if (unlikely(port->irq < 0))
716 return -ENXIO;
717
718 platform_set_drvdata(pdev, port);
719
720 return uart_add_one_port(&msm_uart_driver, port);
721}
722
723static int __devexit msm_serial_remove(struct platform_device *pdev)
724{
725 struct msm_port *msm_port = platform_get_drvdata(pdev);
726
727 clk_put(msm_port->clk);
728
729 return 0;
730}
731
732static struct platform_driver msm_platform_driver = {
733 .remove = msm_serial_remove,
734 .driver = {
735 .name = "msm_serial",
736 .owner = THIS_MODULE,
737 },
738};
739
740static int __init msm_serial_init(void)
741{
742 int ret;
743
744 ret = uart_register_driver(&msm_uart_driver);
745 if (unlikely(ret))
746 return ret;
747
748 ret = platform_driver_probe(&msm_platform_driver, msm_serial_probe);
749 if (unlikely(ret))
750 uart_unregister_driver(&msm_uart_driver);
751
752 printk(KERN_INFO "msm_serial: driver initialized\n");
753
754 return ret;
755}
756
757static void __exit msm_serial_exit(void)
758{
759#ifdef CONFIG_SERIAL_MSM_CONSOLE
760 unregister_console(&msm_console);
761#endif
762 platform_driver_unregister(&msm_platform_driver);
763 uart_unregister_driver(&msm_uart_driver);
764}
765
766module_init(msm_serial_init);
767module_exit(msm_serial_exit);
768
769MODULE_AUTHOR("Robert Love <rlove@google.com>");
770MODULE_DESCRIPTION("Driver for msm7x serial device");
771MODULE_LICENSE("GPL");
772
