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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
[deliverable/linux.git] / drivers / mmc / card / sdio_uart.c
CommitLineData
6e418a9d
NP		 1/*
2 * linux/drivers/mmc/card/sdio_uart.c - SDIO UART/GPS driver
3 *
4 * Based on drivers/serial/8250.c and drivers/serial/serial_core.c
5 * by Russell King.
6 *
7 * Author: Nicolas Pitre
8 * Created: June 15, 2007
9 * Copyright: MontaVista Software, Inc.
10 *
11 * This program is free software; you can redistribute it and/or modify
12 * it under the terms of the GNU General Public License as published by
13 * the Free Software Foundation; either version 2 of the License, or (at
14 * your option) any later version.
15 */
16
17/*
18 * Note: Although this driver assumes a 16550A-like UART implementation,
19 * it is not possible to leverage the common 8250/16550 driver, nor the
20 * core UART infrastructure, as they assumes direct access to the hardware
21 * registers, often under a spinlock. This is not possible in the SDIO
22 * context as SDIO access functions must be able to sleep.
23 *
24 * Because we need to lock the SDIO host to ensure an exclusive access to
25 * the card, we simply rely on that lock to also prevent and serialize
26 * concurrent access to the same port.
27 */
28
29#include <linux/module.h>
30#include <linux/init.h>
31#include <linux/kernel.h>
4b3b49bb 32#include <linux/sched.h>
6e418a9d 33#include <linux/mutex.h>
201a50ba 34#include <linux/seq_file.h>
6e418a9d
NP		 35#include <linux/serial_reg.h>
36#include <linux/circ_buf.h>
6e418a9d
NP		 37#include <linux/tty.h>
38#include <linux/tty_flip.h>
8b197a5c 39#include <linux/kfifo.h>
5a0e3ad6 40#include <linux/slab.h>
6e418a9d
NP		 41
42#include <linux/mmc/core.h>
43#include <linux/mmc/card.h>
44#include <linux/mmc/sdio_func.h>
45#include <linux/mmc/sdio_ids.h>
46
47
48#define UART_NR 8 /* Number of UARTs this driver can handle */
49
50
8b197a5c 51#define FIFO_SIZE PAGE_SIZE
6e418a9d
NP		 52#define WAKEUP_CHARS 256
53
6e418a9d
NP		 54struct uart_icount {
55 __u32 cts;
56 __u32 dsr;
57 __u32 rng;
58 __u32 dcd;
59 __u32 rx;
60 __u32 tx;
61 __u32 frame;
62 __u32 overrun;
63 __u32 parity;
64 __u32 brk;
65};
66
67struct sdio_uart_port {
b5849b1a 68 struct tty_port port;
6e418a9d 69 unsigned int index;
6e418a9d
NP		 70 struct sdio_func *func;
71 struct mutex func_lock;
15b82b46 72 struct task_struct *in_sdio_uart_irq;
6e418a9d 73 unsigned int regs_offset;
8b197a5c 74 struct kfifo xmit_fifo;
6e418a9d
NP		 75 spinlock_t write_lock;
76 struct uart_icount icount;
77 unsigned int uartclk;
78 unsigned int mctrl;
4b3b49bb 79 unsigned int rx_mctrl;
6e418a9d
NP		 80 unsigned int read_status_mask;
81 unsigned int ignore_status_mask;
82 unsigned char x_char;
83 unsigned char ier;
84 unsigned char lcr;
85};
86
87static struct sdio_uart_port *sdio_uart_table[UART_NR];
88static DEFINE_SPINLOCK(sdio_uart_table_lock);
89
90static int sdio_uart_add_port(struct sdio_uart_port *port)
91{
92 int index, ret = -EBUSY;
93
6e418a9d
NP		 94 mutex_init(&port->func_lock);
95 spin_lock_init(&port->write_lock);
8b197a5c
AC		 96 if (kfifo_alloc(&port->xmit_fifo, FIFO_SIZE, GFP_KERNEL))
97 return -ENOMEM;
6e418a9d
NP		 98
99 spin_lock(&sdio_uart_table_lock);
100 for (index = 0; index < UART_NR; index++) {
101 if (!sdio_uart_table[index]) {
102 port->index = index;
103 sdio_uart_table[index] = port;
104 ret = 0;
105 break;
106 }
107 }
108 spin_unlock(&sdio_uart_table_lock);
109
110 return ret;
111}
112
113static struct sdio_uart_port *sdio_uart_port_get(unsigned index)
114{
115 struct sdio_uart_port *port;
116
117 if (index >= UART_NR)
118 return NULL;
119
120 spin_lock(&sdio_uart_table_lock);
121 port = sdio_uart_table[index];
122 if (port)
e70c6771 123 tty_port_get(&port->port);
6e418a9d
NP		 124 spin_unlock(&sdio_uart_table_lock);
125
126 return port;
127}
128
6e418a9d
NP		 129static void sdio_uart_port_put(struct sdio_uart_port *port)
130{
e70c6771 131 tty_port_put(&port->port);
6e418a9d
NP		 132}
133
134static void sdio_uart_port_remove(struct sdio_uart_port *port)
135{
136 struct sdio_func *func;
137
138 BUG_ON(sdio_uart_table[port->index] != port);
139
140 spin_lock(&sdio_uart_table_lock);
141 sdio_uart_table[port->index] = NULL;
142 spin_unlock(&sdio_uart_table_lock);
143
144 /*
145 * We're killing a port that potentially still is in use by
146 * the tty layer. Be careful to prevent any further access
147 * to the SDIO function and arrange for the tty layer to
148 * give up on that port ASAP.
149 * Beware: the lock ordering is critical.
150 */
0a68f64f 151 mutex_lock(&port->port.mutex);
6e418a9d
NP		 152 mutex_lock(&port->func_lock);
153 func = port->func;
154 sdio_claim_host(func);
155 port->func = NULL;
156 mutex_unlock(&port->func_lock);
584abc37 157 /* tty_hangup is async so is this safe as is ?? */
aa27a094 158 tty_port_tty_hangup(&port->port, false);
0a68f64f 159 mutex_unlock(&port->port.mutex);
6e418a9d
NP		 160 sdio_release_irq(func);
161 sdio_disable_func(func);
162 sdio_release_host(func);
163
164 sdio_uart_port_put(port);
165}
166
167static int sdio_uart_claim_func(struct sdio_uart_port *port)
168{
169 mutex_lock(&port->func_lock);
170 if (unlikely(!port->func)) {
171 mutex_unlock(&port->func_lock);
172 return -ENODEV;
173 }
15b82b46
NP		 174 if (likely(port->in_sdio_uart_irq != current))
175 sdio_claim_host(port->func);
6e418a9d
NP		 176 mutex_unlock(&port->func_lock);
177 return 0;
178}
179
180static inline void sdio_uart_release_func(struct sdio_uart_port *port)
181{
15b82b46
NP		 182 if (likely(port->in_sdio_uart_irq != current))
183 sdio_release_host(port->func);
6e418a9d
NP		 184}
185
186static inline unsigned int sdio_in(struct sdio_uart_port *port, int offset)
187{
188 unsigned char c;
189 c = sdio_readb(port->func, port->regs_offset + offset, NULL);
190 return c;
191}
192
193static inline void sdio_out(struct sdio_uart_port *port, int offset, int value)
194{
195 sdio_writeb(port->func, value, port->regs_offset + offset, NULL);
196}
197
198static unsigned int sdio_uart_get_mctrl(struct sdio_uart_port *port)
199{
200 unsigned char status;
201 unsigned int ret;
202
4b3b49bb
AC		 203 /* FIXME: What stops this losing the delta bits and breaking
204 sdio_uart_check_modem_status ? */
6e418a9d
NP		 205 status = sdio_in(port, UART_MSR);
206
207 ret = 0;
208 if (status & UART_MSR_DCD)
209 ret |= TIOCM_CAR;
210 if (status & UART_MSR_RI)
211 ret |= TIOCM_RNG;
212 if (status & UART_MSR_DSR)
213 ret |= TIOCM_DSR;
214 if (status & UART_MSR_CTS)
215 ret |= TIOCM_CTS;
216 return ret;
217}
218
1e04b7ae
TLSC		 219static void sdio_uart_write_mctrl(struct sdio_uart_port *port,
220 unsigned int mctrl)
6e418a9d
NP		 221{
222 unsigned char mcr = 0;
223
224 if (mctrl & TIOCM_RTS)
225 mcr |= UART_MCR_RTS;
226 if (mctrl & TIOCM_DTR)
227 mcr |= UART_MCR_DTR;
228 if (mctrl & TIOCM_OUT1)
229 mcr |= UART_MCR_OUT1;
230 if (mctrl & TIOCM_OUT2)
231 mcr |= UART_MCR_OUT2;
232 if (mctrl & TIOCM_LOOP)
233 mcr |= UART_MCR_LOOP;
234
235 sdio_out(port, UART_MCR, mcr);
236}
237
238static inline void sdio_uart_update_mctrl(struct sdio_uart_port *port,
239 unsigned int set, unsigned int clear)
240{
241 unsigned int old;
242
243 old = port->mctrl;
244 port->mctrl = (old & ~clear) | set;
245 if (old != port->mctrl)
246 sdio_uart_write_mctrl(port, port->mctrl);
247}
248
249#define sdio_uart_set_mctrl(port, x) sdio_uart_update_mctrl(port, x, 0)
250#define sdio_uart_clear_mctrl(port, x) sdio_uart_update_mctrl(port, 0, x)
251
252static void sdio_uart_change_speed(struct sdio_uart_port *port,
253 struct ktermios *termios,
254 struct ktermios *old)
255{
256 unsigned char cval, fcr = 0;
257 unsigned int baud, quot;
258
259 switch (termios->c_cflag & CSIZE) {
260 case CS5:
261 cval = UART_LCR_WLEN5;
262 break;
263 case CS6:
264 cval = UART_LCR_WLEN6;
265 break;
266 case CS7:
267 cval = UART_LCR_WLEN7;
268 break;
269 default:
270 case CS8:
271 cval = UART_LCR_WLEN8;
272 break;
273 }
274
275 if (termios->c_cflag & CSTOPB)
276 cval |= UART_LCR_STOP;
277 if (termios->c_cflag & PARENB)
278 cval |= UART_LCR_PARITY;
279 if (!(termios->c_cflag & PARODD))
280 cval |= UART_LCR_EPAR;
281
282 for (;;) {
283 baud = tty_termios_baud_rate(termios);
284 if (baud == 0)
285 baud = 9600; /* Special case: B0 rate. */
286 if (baud <= port->uartclk)
287 break;
288 /*
289 * Oops, the quotient was zero. Try again with the old
290 * baud rate if possible, otherwise default to 9600.
291 */
292 termios->c_cflag &= ~CBAUD;
293 if (old) {
294 termios->c_cflag |= old->c_cflag & CBAUD;
295 old = NULL;
296 } else
297 termios->c_cflag |= B9600;
298 }
299 quot = (2 * port->uartclk + baud) / (2 * baud);
300
301 if (baud < 2400)
302 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_1;
303 else
304 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10;
305
306 port->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
307 if (termios->c_iflag & INPCK)
308 port->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
309 if (termios->c_iflag & (BRKINT | PARMRK))
310 port->read_status_mask |= UART_LSR_BI;
311
312 /*
313 * Characters to ignore
314 */
315 port->ignore_status_mask = 0;
316 if (termios->c_iflag & IGNPAR)
317 port->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
318 if (termios->c_iflag & IGNBRK) {
319 port->ignore_status_mask |= UART_LSR_BI;
320 /*
321 * If we're ignoring parity and break indicators,
322 * ignore overruns too (for real raw support).
323 */
324 if (termios->c_iflag & IGNPAR)
325 port->ignore_status_mask |= UART_LSR_OE;
326 }
327
328 /*
329 * ignore all characters if CREAD is not set
330 */
331 if ((termios->c_cflag & CREAD) == 0)
332 port->ignore_status_mask |= UART_LSR_DR;
333
334 /*
335 * CTS flow control flag and modem status interrupts
336 */
337 port->ier &= ~UART_IER_MSI;
338 if ((termios->c_cflag & CRTSCTS) || !(termios->c_cflag & CLOCAL))
339 port->ier |= UART_IER_MSI;
340
341 port->lcr = cval;
342
343 sdio_out(port, UART_IER, port->ier);
344 sdio_out(port, UART_LCR, cval | UART_LCR_DLAB);
345 sdio_out(port, UART_DLL, quot & 0xff);
346 sdio_out(port, UART_DLM, quot >> 8);
347 sdio_out(port, UART_LCR, cval);
348 sdio_out(port, UART_FCR, fcr);
349
350 sdio_uart_write_mctrl(port, port->mctrl);
351}
352
353static void sdio_uart_start_tx(struct sdio_uart_port *port)
354{
355 if (!(port->ier & UART_IER_THRI)) {
356 port->ier |= UART_IER_THRI;
357 sdio_out(port, UART_IER, port->ier);
358 }
359}
360
361static void sdio_uart_stop_tx(struct sdio_uart_port *port)
362{
363 if (port->ier & UART_IER_THRI) {
364 port->ier &= ~UART_IER_THRI;
365 sdio_out(port, UART_IER, port->ier);
366 }
367}
368
369static void sdio_uart_stop_rx(struct sdio_uart_port *port)
370{
371 port->ier &= ~UART_IER_RLSI;
372 port->read_status_mask &= ~UART_LSR_DR;
373 sdio_out(port, UART_IER, port->ier);
374}
375
1e04b7ae
TLSC		 376static void sdio_uart_receive_chars(struct sdio_uart_port *port,
377 unsigned int *status)
6e418a9d 378{
6e418a9d
NP		 379 unsigned int ch, flag;
380 int max_count = 256;
381
382 do {
383 ch = sdio_in(port, UART_RX);
384 flag = TTY_NORMAL;
385 port->icount.rx++;
386
387 if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
1e04b7ae 388 UART_LSR_FE | UART_LSR_OE))) {
6e418a9d
NP		 389 /*
390 * For statistics only
391 */
392 if (*status & UART_LSR_BI) {
393 *status &= ~(UART_LSR_FE | UART_LSR_PE);
394 port->icount.brk++;
395 } else if (*status & UART_LSR_PE)
396 port->icount.parity++;
397 else if (*status & UART_LSR_FE)
398 port->icount.frame++;
399 if (*status & UART_LSR_OE)
400 port->icount.overrun++;
401
402 /*
403 * Mask off conditions which should be ignored.
404 */
405 *status &= port->read_status_mask;
1e04b7ae 406 if (*status & UART_LSR_BI)
6e418a9d 407 flag = TTY_BREAK;
1e04b7ae 408 else if (*status & UART_LSR_PE)
6e418a9d
NP		 409 flag = TTY_PARITY;
410 else if (*status & UART_LSR_FE)
411 flag = TTY_FRAME;
412 }
413
414 if ((*status & port->ignore_status_mask & ~UART_LSR_OE) == 0)
2e124b4a 415 tty_insert_flip_char(&port->port, ch, flag);
6e418a9d
NP		 416
417 /*
418 * Overrun is special. Since it's reported immediately,
419 * it doesn't affect the current character.
420 */
421 if (*status & ~port->ignore_status_mask & UART_LSR_OE)
2e124b4a 422 tty_insert_flip_char(&port->port, 0, TTY_OVERRUN);
6e418a9d
NP		 423
424 *status = sdio_in(port, UART_LSR);
425 } while ((*status & UART_LSR_DR) && (max_count-- > 0));
2e124b4a
JS		 426
427 tty_flip_buffer_push(&port->port);
6e418a9d
NP		 428}
429
430static void sdio_uart_transmit_chars(struct sdio_uart_port *port)
431{
8b197a5c 432 struct kfifo *xmit = &port->xmit_fifo;
6e418a9d 433 int count;
530646f4 434 struct tty_struct *tty;
8b197a5c
AC		 435 u8 iobuf[16];
436 int len;
6e418a9d
NP		 437
438 if (port->x_char) {
439 sdio_out(port, UART_TX, port->x_char);
440 port->icount.tx++;
441 port->x_char = 0;
442 return;
443 }
530646f4
AC		 444
445 tty = tty_port_tty_get(&port->port);
446
8b197a5c 447 if (tty == NULL || !kfifo_len(xmit) ||
c271cf37 448 tty->stopped || tty->hw_stopped) {
6e418a9d 449 sdio_uart_stop_tx(port);
530646f4 450 tty_kref_put(tty);
6e418a9d
NP		 451 return;
452 }
453
8b197a5c
AC		 454 len = kfifo_out_locked(xmit, iobuf, 16, &port->write_lock);
455 for (count = 0; count < len; count++) {
456 sdio_out(port, UART_TX, iobuf[count]);
6e418a9d 457 port->icount.tx++;
8b197a5c 458 }
6e418a9d 459
8b197a5c
AC		 460 len = kfifo_len(xmit);
461 if (len < WAKEUP_CHARS) {
b5849b1a 462 tty_wakeup(tty);
8b197a5c
AC		 463 if (len == 0)
464 sdio_uart_stop_tx(port);
465 }
530646f4 466 tty_kref_put(tty);
6e418a9d
NP		 467}
468
469static void sdio_uart_check_modem_status(struct sdio_uart_port *port)
470{
471 int status;
530646f4 472 struct tty_struct *tty;
6e418a9d
NP		 473
474 status = sdio_in(port, UART_MSR);
475
476 if ((status & UART_MSR_ANY_DELTA) == 0)
477 return;
478
479 if (status & UART_MSR_TERI)
480 port->icount.rng++;
481 if (status & UART_MSR_DDSR)
482 port->icount.dsr++;
4b3b49bb 483 if (status & UART_MSR_DDCD) {
6e418a9d 484 port->icount.dcd++;
4b3b49bb
AC		 485 /* DCD raise - wake for open */
486 if (status & UART_MSR_DCD)
487 wake_up_interruptible(&port->port.open_wait);
488 else {
489 /* DCD drop - hang up if tty attached */
aa27a094 490 tty_port_tty_hangup(&port->port, false);
4b3b49bb
AC		 491 }
492 }
6e418a9d
NP		 493 if (status & UART_MSR_DCTS) {
494 port->icount.cts++;
530646f4 495 tty = tty_port_tty_get(&port->port);
adc8d746 496 if (tty && (tty->termios.c_cflag & CRTSCTS)) {
6e418a9d 497 int cts = (status & UART_MSR_CTS);
b5849b1a 498 if (tty->hw_stopped) {
6e418a9d 499 if (cts) {
b5849b1a 500 tty->hw_stopped = 0;
6e418a9d 501 sdio_uart_start_tx(port);
b5849b1a 502 tty_wakeup(tty);
6e418a9d
NP		 503 }
504 } else {
505 if (!cts) {
b5849b1a 506 tty->hw_stopped = 1;
6e418a9d
NP		 507 sdio_uart_stop_tx(port);
508 }
509 }
510 }
530646f4 511 tty_kref_put(tty);
6e418a9d
NP		 512 }
513}
514
515/*
516 * This handles the interrupt from one port.
517 */
518static void sdio_uart_irq(struct sdio_func *func)
519{
520 struct sdio_uart_port *port = sdio_get_drvdata(func);
521 unsigned int iir, lsr;
522
15b82b46
NP		 523 /*
524 * In a few places sdio_uart_irq() is called directly instead of
525 * waiting for the actual interrupt to be raised and the SDIO IRQ
526 * thread scheduled in order to reduce latency. However, some
527 * interaction with the tty core may end up calling us back
528 * (serial echo, flow control, etc.) through those same places
529 * causing undesirable effects. Let's stop the recursion here.
530 */
531 if (unlikely(port->in_sdio_uart_irq == current))
532 return;
533
6e418a9d
NP		 534 iir = sdio_in(port, UART_IIR);
535 if (iir & UART_IIR_NO_INT)
536 return;
15b82b46
NP		 537
538 port->in_sdio_uart_irq = current;
6e418a9d
NP		 539 lsr = sdio_in(port, UART_LSR);
540 if (lsr & UART_LSR_DR)
541 sdio_uart_receive_chars(port, &lsr);
542 sdio_uart_check_modem_status(port);
543 if (lsr & UART_LSR_THRE)
544 sdio_uart_transmit_chars(port);
15b82b46 545 port->in_sdio_uart_irq = NULL;
6e418a9d
NP		 546}
547
4b3b49bb
AC		 548static int uart_carrier_raised(struct tty_port *tport)
549{
550 struct sdio_uart_port *port =
551 container_of(tport, struct sdio_uart_port, port);
552 unsigned int ret = sdio_uart_claim_func(port);
c9404c9c 553 if (ret) /* Missing hardware shouldn't block for carrier */
4b3b49bb
AC		 554 return 1;
555 ret = sdio_uart_get_mctrl(port);
556 sdio_uart_release_func(port);
557 if (ret & TIOCM_CAR)
558 return 1;
559 return 0;
560}
561
584abc37
AC		 562/**
563 * uart_dtr_rts - port helper to set uart signals
564 * @tport: tty port to be updated
565 * @onoff: set to turn on DTR/RTS
566 *
567 * Called by the tty port helpers when the modem signals need to be
568 * adjusted during an open, close and hangup.
569 */
570
571static void uart_dtr_rts(struct tty_port *tport, int onoff)
6e418a9d 572{
584abc37
AC		 573 struct sdio_uart_port *port =
574 container_of(tport, struct sdio_uart_port, port);
1f100b32
AC		 575 int ret = sdio_uart_claim_func(port);
576 if (ret)
577 return;
584abc37
AC		 578 if (onoff == 0)
579 sdio_uart_clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);
580 else
581 sdio_uart_set_mctrl(port, TIOCM_DTR | TIOCM_RTS);
1f100b32 582 sdio_uart_release_func(port);
584abc37 583}
530646f4 584
584abc37
AC		 585/**
586 * sdio_uart_activate - start up hardware
587 * @tport: tty port to activate
588 * @tty: tty bound to this port
589 *
590 * Activate a tty port. The port locking guarantees us this will be
591 * run exactly once per set of opens, and if successful will see the
592 * shutdown method run exactly once to match. Start up and shutdown are
593 * protected from each other by the internal locking and will not run
594 * at the same time even during a hangup event.
595 *
596 * If we successfully start up the port we take an extra kref as we
597 * will keep it around until shutdown when the kref is dropped.
598 */
599
600static int sdio_uart_activate(struct tty_port *tport, struct tty_struct *tty)
601{
602 struct sdio_uart_port *port =
603 container_of(tport, struct sdio_uart_port, port);
584abc37 604 int ret;
6e418a9d
NP		 605
606 /*
607 * Set the TTY IO error marker - we will only clear this
608 * once we have successfully opened the port.
609 */
b5849b1a 610 set_bit(TTY_IO_ERROR, &tty->flags);
6e418a9d 611
8b197a5c 612 kfifo_reset(&port->xmit_fifo);
6e418a9d
NP		 613
614 ret = sdio_uart_claim_func(port);
615 if (ret)
8b197a5c 616 return ret;
6e418a9d
NP		 617 ret = sdio_enable_func(port->func);
618 if (ret)
8b197a5c 619 goto err1;
6e418a9d
NP		 620 ret = sdio_claim_irq(port->func, sdio_uart_irq);
621 if (ret)
8b197a5c 622 goto err2;
6e418a9d
NP		 623
624 /*
625 * Clear the FIFO buffers and disable them.
626 * (they will be reenabled in sdio_change_speed())
627 */
628 sdio_out(port, UART_FCR, UART_FCR_ENABLE_FIFO);
629 sdio_out(port, UART_FCR, UART_FCR_ENABLE_FIFO |
1e04b7ae 630 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
6e418a9d
NP		 631 sdio_out(port, UART_FCR, 0);
632
633 /*
634 * Clear the interrupt registers.
635 */
636 (void) sdio_in(port, UART_LSR);
637 (void) sdio_in(port, UART_RX);
638 (void) sdio_in(port, UART_IIR);
639 (void) sdio_in(port, UART_MSR);
640
641 /*
642 * Now, initialize the UART
643 */
644 sdio_out(port, UART_LCR, UART_LCR_WLEN8);
645
c271cf37 646 port->ier = UART_IER_RLSI|UART_IER_RDI|UART_IER_RTOIE|UART_IER_UUE;
6e418a9d
NP		 647 port->mctrl = TIOCM_OUT2;
648
adc8d746 649 sdio_uart_change_speed(port, &tty->termios, NULL);
6e418a9d 650
adc8d746 651 if (tty->termios.c_cflag & CBAUD)
6e418a9d
NP		 652 sdio_uart_set_mctrl(port, TIOCM_RTS | TIOCM_DTR);
653
adc8d746 654 if (tty->termios.c_cflag & CRTSCTS)
6e418a9d 655 if (!(sdio_uart_get_mctrl(port) & TIOCM_CTS))
b5849b1a 656 tty->hw_stopped = 1;
6e418a9d 657
0395b48c 658 clear_bit(TTY_IO_ERROR, &tty->flags);
6e418a9d
NP		 659
660 /* Kick the IRQ handler once while we're still holding the host lock */
661 sdio_uart_irq(port->func);
662
663 sdio_uart_release_func(port);
664 return 0;
665
6e418a9d 666err2:
8b197a5c 667 sdio_disable_func(port->func);
6e418a9d 668err1:
8b197a5c 669 sdio_uart_release_func(port);
6e418a9d
NP		 670 return ret;
671}
672
584abc37
AC		 673/**
674 * sdio_uart_shutdown - stop hardware
675 * @tport: tty port to shut down
676 *
677 * Deactivate a tty port. The port locking guarantees us this will be
678 * run only if a successful matching activate already ran. The two are
679 * protected from each other by the internal locking and will not run
680 * at the same time even during a hangup event.
681 */
682
683static void sdio_uart_shutdown(struct tty_port *tport)
6e418a9d 684{
584abc37
AC		 685 struct sdio_uart_port *port =
686 container_of(tport, struct sdio_uart_port, port);
6e418a9d
NP		 687 int ret;
688
689 ret = sdio_uart_claim_func(port);
690 if (ret)
8b197a5c 691 return;
6e418a9d
NP		 692
693 sdio_uart_stop_rx(port);
694
1e04b7ae 695 /* Disable interrupts from this port */
6e418a9d
NP		 696 sdio_release_irq(port->func);
697 port->ier = 0;
698 sdio_out(port, UART_IER, 0);
699
700 sdio_uart_clear_mctrl(port, TIOCM_OUT2);
701
702 /* Disable break condition and FIFOs. */
703 port->lcr &= ~UART_LCR_SBC;
704 sdio_out(port, UART_LCR, port->lcr);
705 sdio_out(port, UART_FCR, UART_FCR_ENABLE_FIFO |
706 UART_FCR_CLEAR_RCVR |
707 UART_FCR_CLEAR_XMIT);
708 sdio_out(port, UART_FCR, 0);
709
710 sdio_disable_func(port->func);
711
712 sdio_uart_release_func(port);
6e418a9d
NP		 713}
714
e70c6771
JS		 715static void sdio_uart_port_destroy(struct tty_port *tport)
716{
717 struct sdio_uart_port *port =
718 container_of(tport, struct sdio_uart_port, port);
719 kfifo_free(&port->xmit_fifo);
720 kfree(port);
721}
722
584abc37
AC		 723/**
724 * sdio_uart_install - install method
725 * @driver: the driver in use (sdio_uart in our case)
726 * @tty: the tty being bound
727 *
728 * Look up and bind the tty and the driver together. Initialize
729 * any needed private data (in our case the termios)
730 */
6e418a9d 731
584abc37
AC		 732static int sdio_uart_install(struct tty_driver *driver, struct tty_struct *tty)
733{
734 int idx = tty->index;
735 struct sdio_uart_port *port = sdio_uart_port_get(idx);
81f5835e 736 int ret = tty_standard_install(driver, tty);
584abc37 737
81f5835e 738 if (ret == 0)
584abc37
AC		 739 /* This is the ref sdio_uart_port get provided */
740 tty->driver_data = port;
81f5835e 741 else
6e418a9d 742 sdio_uart_port_put(port);
584abc37 743 return ret;
6e418a9d
NP		 744}
745
584abc37
AC		 746/**
747 * sdio_uart_cleanup - called on the last tty kref drop
748 * @tty: the tty being destroyed
749 *
750 * Called asynchronously when the last reference to the tty is dropped.
751 * We cannot destroy the tty->driver_data port kref until this point
752 */
753
754static void sdio_uart_cleanup(struct tty_struct *tty)
6e418a9d
NP		 755{
756 struct sdio_uart_port *port = tty->driver_data;
584abc37
AC		 757 tty->driver_data = NULL; /* Bug trap */
758 sdio_uart_port_put(port);
759}
6e418a9d 760
584abc37
AC		 761/*
762 * Open/close/hangup is now entirely boilerplate
763 */
6e418a9d 764
584abc37
AC		 765static int sdio_uart_open(struct tty_struct *tty, struct file *filp)
766{
767 struct sdio_uart_port *port = tty->driver_data;
768 return tty_port_open(&port->port, tty, filp);
769}
6e418a9d 770
584abc37
AC		 771static void sdio_uart_close(struct tty_struct *tty, struct file * filp)
772{
773 struct sdio_uart_port *port = tty->driver_data;
774 tty_port_close(&port->port, tty, filp);
775}
6e418a9d 776
584abc37
AC		 777static void sdio_uart_hangup(struct tty_struct *tty)
778{
779 struct sdio_uart_port *port = tty->driver_data;
780 tty_port_hangup(&port->port);
6e418a9d
NP		 781}
782
c271cf37 783static int sdio_uart_write(struct tty_struct *tty, const unsigned char *buf,
6e418a9d
NP		 784 int count)
785{
786 struct sdio_uart_port *port = tty->driver_data;
8b197a5c 787 int ret;
6e418a9d
NP		 788
789 if (!port->func)
790 return -ENODEV;
791
8b197a5c 792 ret = kfifo_in_locked(&port->xmit_fifo, buf, count, &port->write_lock);
c271cf37 793 if (!(port->ier & UART_IER_THRI)) {
6e418a9d
NP		 794 int err = sdio_uart_claim_func(port);
795 if (!err) {
796 sdio_uart_start_tx(port);
797 sdio_uart_irq(port->func);
798 sdio_uart_release_func(port);
799 } else
800 ret = err;
801 }
802
803 return ret;
804}
805
806static int sdio_uart_write_room(struct tty_struct *tty)
807{
808 struct sdio_uart_port *port = tty->driver_data;
8b197a5c 809 return FIFO_SIZE - kfifo_len(&port->xmit_fifo);
6e418a9d
NP		 810}
811
812static int sdio_uart_chars_in_buffer(struct tty_struct *tty)
813{
814 struct sdio_uart_port *port = tty->driver_data;
8b197a5c 815 return kfifo_len(&port->xmit_fifo);
6e418a9d
NP		 816}
817
818static void sdio_uart_send_xchar(struct tty_struct *tty, char ch)
819{
820 struct sdio_uart_port *port = tty->driver_data;
821
822 port->x_char = ch;
823 if (ch && !(port->ier & UART_IER_THRI)) {
824 if (sdio_uart_claim_func(port) != 0)
825 return;
826 sdio_uart_start_tx(port);
827 sdio_uart_irq(port->func);
828 sdio_uart_release_func(port);
829 }
830}
831
832static void sdio_uart_throttle(struct tty_struct *tty)
833{
834 struct sdio_uart_port *port = tty->driver_data;
835
adc8d746 836 if (!I_IXOFF(tty) && !(tty->termios.c_cflag & CRTSCTS))
6e418a9d
NP		 837 return;
838
839 if (sdio_uart_claim_func(port) != 0)
840 return;
841
842 if (I_IXOFF(tty)) {
843 port->x_char = STOP_CHAR(tty);
844 sdio_uart_start_tx(port);
845 }
846
adc8d746 847 if (tty->termios.c_cflag & CRTSCTS)
6e418a9d
NP		 848 sdio_uart_clear_mctrl(port, TIOCM_RTS);
849
850 sdio_uart_irq(port->func);
851 sdio_uart_release_func(port);
852}
853
854static void sdio_uart_unthrottle(struct tty_struct *tty)
855{
856 struct sdio_uart_port *port = tty->driver_data;
857
adc8d746 858 if (!I_IXOFF(tty) && !(tty->termios.c_cflag & CRTSCTS))
6e418a9d
NP		 859 return;
860
861 if (sdio_uart_claim_func(port) != 0)
862 return;
863
864 if (I_IXOFF(tty)) {
865 if (port->x_char) {
866 port->x_char = 0;
867 } else {
868 port->x_char = START_CHAR(tty);
869 sdio_uart_start_tx(port);
870 }
871 }
872
adc8d746 873 if (tty->termios.c_cflag & CRTSCTS)
6e418a9d
NP		 874 sdio_uart_set_mctrl(port, TIOCM_RTS);
875
876 sdio_uart_irq(port->func);
877 sdio_uart_release_func(port);
878}
879
c271cf37
AC		 880static void sdio_uart_set_termios(struct tty_struct *tty,
881 struct ktermios *old_termios)
6e418a9d
NP		 882{
883 struct sdio_uart_port *port = tty->driver_data;
adc8d746 884 unsigned int cflag = tty->termios.c_cflag;
6e418a9d 885
6e418a9d
NP		 886 if (sdio_uart_claim_func(port) != 0)
887 return;
888
adc8d746 889 sdio_uart_change_speed(port, &tty->termios, old_termios);
6e418a9d
NP		 890
891 /* Handle transition to B0 status */
892 if ((old_termios->c_cflag & CBAUD) && !(cflag & CBAUD))
893 sdio_uart_clear_mctrl(port, TIOCM_RTS | TIOCM_DTR);
894
895 /* Handle transition away from B0 status */
896 if (!(old_termios->c_cflag & CBAUD) && (cflag & CBAUD)) {
897 unsigned int mask = TIOCM_DTR;
898 if (!(cflag & CRTSCTS) || !test_bit(TTY_THROTTLED, &tty->flags))
899 mask |= TIOCM_RTS;
900 sdio_uart_set_mctrl(port, mask);
901 }
902
903 /* Handle turning off CRTSCTS */
904 if ((old_termios->c_cflag & CRTSCTS) && !(cflag & CRTSCTS)) {
905 tty->hw_stopped = 0;
906 sdio_uart_start_tx(port);
907 }
908
909 /* Handle turning on CRTSCTS */
910 if (!(old_termios->c_cflag & CRTSCTS) && (cflag & CRTSCTS)) {
911 if (!(sdio_uart_get_mctrl(port) & TIOCM_CTS)) {
912 tty->hw_stopped = 1;
913 sdio_uart_stop_tx(port);
914 }
915 }
916
917 sdio_uart_release_func(port);
918}
919
c43d8636 920static int sdio_uart_break_ctl(struct tty_struct *tty, int break_state)
6e418a9d
NP		 921{
922 struct sdio_uart_port *port = tty->driver_data;
c43d8636 923 int result;
6e418a9d 924
c43d8636
DH		 925 result = sdio_uart_claim_func(port);
926 if (result != 0)
927 return result;
6e418a9d
NP		 928
929 if (break_state == -1)
930 port->lcr |= UART_LCR_SBC;
931 else
932 port->lcr &= ~UART_LCR_SBC;
933 sdio_out(port, UART_LCR, port->lcr);
934
935 sdio_uart_release_func(port);
c43d8636 936 return 0;
6e418a9d
NP		 937}
938
60b33c13 939static int sdio_uart_tiocmget(struct tty_struct *tty)
6e418a9d
NP		 940{
941 struct sdio_uart_port *port = tty->driver_data;
942 int result;
943
944 result = sdio_uart_claim_func(port);
945 if (!result) {
946 result = port->mctrl | sdio_uart_get_mctrl(port);
947 sdio_uart_release_func(port);
948 }
949
950 return result;
951}
952
20b9d177 953static int sdio_uart_tiocmset(struct tty_struct *tty,
6e418a9d
NP		 954 unsigned int set, unsigned int clear)
955{
956 struct sdio_uart_port *port = tty->driver_data;
957 int result;
958
1e04b7ae 959 result = sdio_uart_claim_func(port);
c271cf37 960 if (!result) {
6e418a9d
NP		 961 sdio_uart_update_mctrl(port, set, clear);
962 sdio_uart_release_func(port);
963 }
964
965 return result;
966}
967
201a50ba 968static int sdio_uart_proc_show(struct seq_file *m, void *v)
5ed334a1 969{
201a50ba 970 int i;
5ed334a1 971
201a50ba 972 seq_printf(m, "serinfo:1.0 driver%s%s revision:%s\n",
5ed334a1 973 "", "", "");
201a50ba 974 for (i = 0; i < UART_NR; i++) {
5ed334a1
NP		 975 struct sdio_uart_port *port = sdio_uart_port_get(i);
976 if (port) {
201a50ba 977 seq_printf(m, "%d: uart:SDIO", i);
c271cf37 978 if (capable(CAP_SYS_ADMIN)) {
201a50ba 979 seq_printf(m, " tx:%d rx:%d",
1e04b7ae 980 port->icount.tx, port->icount.rx);
5ed334a1 981 if (port->icount.frame)
201a50ba 982 seq_printf(m, " fe:%d",
1e04b7ae 983 port->icount.frame);
5ed334a1 984 if (port->icount.parity)
201a50ba 985 seq_printf(m, " pe:%d",
1e04b7ae 986 port->icount.parity);
5ed334a1 987 if (port->icount.brk)
201a50ba 988 seq_printf(m, " brk:%d",
1e04b7ae 989 port->icount.brk);
5ed334a1 990 if (port->icount.overrun)
201a50ba 991 seq_printf(m, " oe:%d",
1e04b7ae 992 port->icount.overrun);
5ed334a1 993 if (port->icount.cts)
201a50ba 994 seq_printf(m, " cts:%d",
1e04b7ae 995 port->icount.cts);
5ed334a1 996 if (port->icount.dsr)
201a50ba 997 seq_printf(m, " dsr:%d",
1e04b7ae 998 port->icount.dsr);
5ed334a1 999 if (port->icount.rng)
201a50ba 1000 seq_printf(m, " rng:%d",
1e04b7ae 1001 port->icount.rng);
5ed334a1 1002 if (port->icount.dcd)
201a50ba 1003 seq_printf(m, " dcd:%d",
1e04b7ae 1004 port->icount.dcd);
5ed334a1 1005 }
5ed334a1 1006 sdio_uart_port_put(port);
201a50ba 1007 seq_putc(m, '\n');
5ed334a1
NP		 1008 }
1009 }
201a50ba
AD		 1010 return 0;
1011}
5ed334a1 1012
201a50ba
AD		 1013static int sdio_uart_proc_open(struct inode *inode, struct file *file)
1014{
1015 return single_open(file, sdio_uart_proc_show, NULL);
5ed334a1
NP		 1016}
1017
201a50ba
AD		 1018static const struct file_operations sdio_uart_proc_fops = {
1019 .owner = THIS_MODULE,
1020 .open = sdio_uart_proc_open,
1021 .read = seq_read,
1022 .llseek = seq_lseek,
1023 .release = single_release,
1024};
1025
584abc37
AC		 1026static const struct tty_port_operations sdio_uart_port_ops = {
1027 .dtr_rts = uart_dtr_rts,
4b3b49bb 1028 .carrier_raised = uart_carrier_raised,
584abc37
AC		 1029 .shutdown = sdio_uart_shutdown,
1030 .activate = sdio_uart_activate,
e70c6771 1031 .destruct = sdio_uart_port_destroy,
584abc37
AC		 1032};
1033
6e418a9d
NP		 1034static const struct tty_operations sdio_uart_ops = {
1035 .open = sdio_uart_open,
1036 .close = sdio_uart_close,
1037 .write = sdio_uart_write,
1038 .write_room = sdio_uart_write_room,
1039 .chars_in_buffer = sdio_uart_chars_in_buffer,
1040 .send_xchar = sdio_uart_send_xchar,
1041 .throttle = sdio_uart_throttle,
1042 .unthrottle = sdio_uart_unthrottle,
1043 .set_termios = sdio_uart_set_termios,
584abc37 1044 .hangup = sdio_uart_hangup,
6e418a9d
NP		 1045 .break_ctl = sdio_uart_break_ctl,
1046 .tiocmget = sdio_uart_tiocmget,
1047 .tiocmset = sdio_uart_tiocmset,
584abc37
AC		 1048 .install = sdio_uart_install,
1049 .cleanup = sdio_uart_cleanup,
201a50ba 1050 .proc_fops = &sdio_uart_proc_fops,
6e418a9d
NP		 1051};
1052
1053static struct tty_driver *sdio_uart_tty_driver;
1054
1055static int sdio_uart_probe(struct sdio_func *func,
1056 const struct sdio_device_id *id)
1057{
1058 struct sdio_uart_port *port;
1059 int ret;
1060
1061 port = kzalloc(sizeof(struct sdio_uart_port), GFP_KERNEL);
1062 if (!port)
1063 return -ENOMEM;
1064
1065 if (func->class == SDIO_CLASS_UART) {
6606110d
JP		 1066 pr_warn("%s: need info on UART class basic setup\n",
1067 sdio_func_id(func));
6e418a9d
NP		 1068 kfree(port);
1069 return -ENOSYS;
1070 } else if (func->class == SDIO_CLASS_GPS) {
1071 /*
1072 * We need tuple 0x91. It contains SUBTPL_SIOREG
1073 * and SUBTPL_RCVCAPS.
1074 */
1075 struct sdio_func_tuple *tpl;
1076 for (tpl = func->tuples; tpl; tpl = tpl->next) {
1077 if (tpl->code != 0x91)
1078 continue;
1079 if (tpl->size < 10)
1080 continue;
1081 if (tpl->data[1] == 0) /* SUBTPL_SIOREG */
1082 break;
1083 }
1084 if (!tpl) {
6606110d
JP		 1085 pr_warn("%s: can't find tuple 0x91 subtuple 0 (SUBTPL_SIOREG) for GPS class\n",
1086 sdio_func_id(func));
6e418a9d
NP		 1087 kfree(port);
1088 return -EINVAL;
1089 }
a3c76eb9 1090 pr_debug("%s: Register ID = 0x%02x, Exp ID = 0x%02x\n",
6e418a9d
NP		 1091 sdio_func_id(func), tpl->data[2], tpl->data[3]);
1092 port->regs_offset = (tpl->data[4] << 0) |
1093 (tpl->data[5] << 8) |
1094 (tpl->data[6] << 16);
a3c76eb9 1095 pr_debug("%s: regs offset = 0x%x\n",
6e418a9d
NP		 1096 sdio_func_id(func), port->regs_offset);
1097 port->uartclk = tpl->data[7] * 115200;
1098 if (port->uartclk == 0)
1099 port->uartclk = 115200;
a3c76eb9 1100 pr_debug("%s: clk %d baudcode %u 4800-div %u\n",
6e418a9d
NP		 1101 sdio_func_id(func), port->uartclk,
1102 tpl->data[7], tpl->data[8] | (tpl->data[9] << 8));
1103 } else {
1104 kfree(port);
1105 return -EINVAL;
1106 }
1107
1108 port->func = func;
1109 sdio_set_drvdata(func, port);
b5849b1a 1110 tty_port_init(&port->port);
584abc37 1111 port->port.ops = &sdio_uart_port_ops;
6e418a9d
NP		 1112
1113 ret = sdio_uart_add_port(port);
1114 if (ret) {
1115 kfree(port);
1116 } else {
1117 struct device *dev;
734cc178
JS		 1118 dev = tty_port_register_device(&port->port,
1119 sdio_uart_tty_driver, port->index, &func->dev);
6e418a9d
NP		 1120 if (IS_ERR(dev)) {
1121 sdio_uart_port_remove(port);
1122 ret = PTR_ERR(dev);
1123 }
1124 }
1125
1126 return ret;
1127}
1128
1129static void sdio_uart_remove(struct sdio_func *func)
1130{
1131 struct sdio_uart_port *port = sdio_get_drvdata(func);
1132
1133 tty_unregister_device(sdio_uart_tty_driver, port->index);
1134 sdio_uart_port_remove(port);
1135}
1136
1137static const struct sdio_device_id sdio_uart_ids[] = {
1138 { SDIO_DEVICE_CLASS(SDIO_CLASS_UART) },
1139 { SDIO_DEVICE_CLASS(SDIO_CLASS_GPS) },
1140 { /* end: all zeroes */ },
1141};
1142
1143MODULE_DEVICE_TABLE(sdio, sdio_uart_ids);
1144
1145static struct sdio_driver sdio_uart_driver = {
1146 .probe = sdio_uart_probe,
1147 .remove = sdio_uart_remove,
1148 .name = "sdio_uart",
1149 .id_table = sdio_uart_ids,
1150};
1151
1152static int __init sdio_uart_init(void)
1153{
1154 int ret;
1155 struct tty_driver *tty_drv;
1156
1157 sdio_uart_tty_driver = tty_drv = alloc_tty_driver(UART_NR);
1158 if (!tty_drv)
1159 return -ENOMEM;
1160
6e418a9d
NP		 1161 tty_drv->driver_name = "sdio_uart";
1162 tty_drv->name = "ttySDIO";
1163 tty_drv->major = 0; /* dynamically allocated */
1164 tty_drv->minor_start = 0;
1165 tty_drv->type = TTY_DRIVER_TYPE_SERIAL;
1166 tty_drv->subtype = SERIAL_TYPE_NORMAL;
1167 tty_drv->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
1168 tty_drv->init_termios = tty_std_termios;
1169 tty_drv->init_termios.c_cflag = B4800 | CS8 | CREAD | HUPCL | CLOCAL;
2ba30eed
NP		 1170 tty_drv->init_termios.c_ispeed = 4800;
1171 tty_drv->init_termios.c_ospeed = 4800;
6e418a9d
NP		 1172 tty_set_operations(tty_drv, &sdio_uart_ops);
1173
1174 ret = tty_register_driver(tty_drv);
1175 if (ret)
1176 goto err1;
1177
1178 ret = sdio_register_driver(&sdio_uart_driver);
1179 if (ret)
1180 goto err2;
1181
1182 return 0;
1183
1184err2:
1185 tty_unregister_driver(tty_drv);
1186err1:
1187 put_tty_driver(tty_drv);
1188 return ret;
1189}
1190
1191static void __exit sdio_uart_exit(void)
1192{
1193 sdio_unregister_driver(&sdio_uart_driver);
1194 tty_unregister_driver(sdio_uart_tty_driver);
1195 put_tty_driver(sdio_uart_tty_driver);
1196}
1197
1198module_init(sdio_uart_init);
1199module_exit(sdio_uart_exit);
1200
1201MODULE_AUTHOR("Nicolas Pitre");
1202MODULE_LICENSE("GPL");
Linux kernel - Deliverables
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