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sdio_uart: use tty_port
[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>
32#include <linux/mutex.h>
201a50ba 33#include <linux/seq_file.h>
6e418a9d
NP		 34#include <linux/serial_reg.h>
35#include <linux/circ_buf.h>
36#include <linux/gfp.h>
37#include <linux/tty.h>
38#include <linux/tty_flip.h>
39
40#include <linux/mmc/core.h>
41#include <linux/mmc/card.h>
42#include <linux/mmc/sdio_func.h>
43#include <linux/mmc/sdio_ids.h>
44
45
46#define UART_NR 8 /* Number of UARTs this driver can handle */
47
48
49#define UART_XMIT_SIZE PAGE_SIZE
50#define WAKEUP_CHARS 256
51
52#define circ_empty(circ) ((circ)->head == (circ)->tail)
53#define circ_clear(circ) ((circ)->head = (circ)->tail = 0)
54
55#define circ_chars_pending(circ) \
56 (CIRC_CNT((circ)->head, (circ)->tail, UART_XMIT_SIZE))
57
58#define circ_chars_free(circ) \
59 (CIRC_SPACE((circ)->head, (circ)->tail, UART_XMIT_SIZE))
60
61
62struct uart_icount {
63 __u32 cts;
64 __u32 dsr;
65 __u32 rng;
66 __u32 dcd;
67 __u32 rx;
68 __u32 tx;
69 __u32 frame;
70 __u32 overrun;
71 __u32 parity;
72 __u32 brk;
73};
74
75struct sdio_uart_port {
b5849b1a 76 struct tty_port port;
6e418a9d
NP		 77 struct kref kref;
78 struct tty_struct *tty;
79 unsigned int index;
80 unsigned int opened;
81 struct mutex open_lock;
82 struct sdio_func *func;
83 struct mutex func_lock;
15b82b46 84 struct task_struct *in_sdio_uart_irq;
6e418a9d
NP		 85 unsigned int regs_offset;
86 struct circ_buf xmit;
87 spinlock_t write_lock;
88 struct uart_icount icount;
89 unsigned int uartclk;
90 unsigned int mctrl;
91 unsigned int read_status_mask;
92 unsigned int ignore_status_mask;
93 unsigned char x_char;
94 unsigned char ier;
95 unsigned char lcr;
96};
97
98static struct sdio_uart_port *sdio_uart_table[UART_NR];
99static DEFINE_SPINLOCK(sdio_uart_table_lock);
100
101static int sdio_uart_add_port(struct sdio_uart_port *port)
102{
103 int index, ret = -EBUSY;
104
105 kref_init(&port->kref);
106 mutex_init(&port->open_lock);
107 mutex_init(&port->func_lock);
108 spin_lock_init(&port->write_lock);
109
110 spin_lock(&sdio_uart_table_lock);
111 for (index = 0; index < UART_NR; index++) {
112 if (!sdio_uart_table[index]) {
113 port->index = index;
114 sdio_uart_table[index] = port;
115 ret = 0;
116 break;
117 }
118 }
119 spin_unlock(&sdio_uart_table_lock);
120
121 return ret;
122}
123
124static struct sdio_uart_port *sdio_uart_port_get(unsigned index)
125{
126 struct sdio_uart_port *port;
127
128 if (index >= UART_NR)
129 return NULL;
130
131 spin_lock(&sdio_uart_table_lock);
132 port = sdio_uart_table[index];
133 if (port)
134 kref_get(&port->kref);
135 spin_unlock(&sdio_uart_table_lock);
136
137 return port;
138}
139
140static void sdio_uart_port_destroy(struct kref *kref)
141{
142 struct sdio_uart_port *port =
143 container_of(kref, struct sdio_uart_port, kref);
144 kfree(port);
145}
146
147static void sdio_uart_port_put(struct sdio_uart_port *port)
148{
149 kref_put(&port->kref, sdio_uart_port_destroy);
150}
151
152static void sdio_uart_port_remove(struct sdio_uart_port *port)
153{
154 struct sdio_func *func;
155
156 BUG_ON(sdio_uart_table[port->index] != port);
157
158 spin_lock(&sdio_uart_table_lock);
159 sdio_uart_table[port->index] = NULL;
160 spin_unlock(&sdio_uart_table_lock);
161
162 /*
163 * We're killing a port that potentially still is in use by
164 * the tty layer. Be careful to prevent any further access
165 * to the SDIO function and arrange for the tty layer to
166 * give up on that port ASAP.
167 * Beware: the lock ordering is critical.
168 */
169 mutex_lock(&port->open_lock);
170 mutex_lock(&port->func_lock);
171 func = port->func;
172 sdio_claim_host(func);
173 port->func = NULL;
174 mutex_unlock(&port->func_lock);
175 if (port->opened)
b5849b1a 176 tty_hangup(port->port.tty);
6e418a9d
NP		 177 mutex_unlock(&port->open_lock);
178 sdio_release_irq(func);
179 sdio_disable_func(func);
180 sdio_release_host(func);
181
182 sdio_uart_port_put(port);
183}
184
185static int sdio_uart_claim_func(struct sdio_uart_port *port)
186{
187 mutex_lock(&port->func_lock);
188 if (unlikely(!port->func)) {
189 mutex_unlock(&port->func_lock);
190 return -ENODEV;
191 }
15b82b46
NP		 192 if (likely(port->in_sdio_uart_irq != current))
193 sdio_claim_host(port->func);
6e418a9d
NP		 194 mutex_unlock(&port->func_lock);
195 return 0;
196}
197
198static inline void sdio_uart_release_func(struct sdio_uart_port *port)
199{
15b82b46
NP		 200 if (likely(port->in_sdio_uart_irq != current))
201 sdio_release_host(port->func);
6e418a9d
NP		 202}
203
204static inline unsigned int sdio_in(struct sdio_uart_port *port, int offset)
205{
206 unsigned char c;
207 c = sdio_readb(port->func, port->regs_offset + offset, NULL);
208 return c;
209}
210
211static inline void sdio_out(struct sdio_uart_port *port, int offset, int value)
212{
213 sdio_writeb(port->func, value, port->regs_offset + offset, NULL);
214}
215
216static unsigned int sdio_uart_get_mctrl(struct sdio_uart_port *port)
217{
218 unsigned char status;
219 unsigned int ret;
220
221 status = sdio_in(port, UART_MSR);
222
223 ret = 0;
224 if (status & UART_MSR_DCD)
225 ret |= TIOCM_CAR;
226 if (status & UART_MSR_RI)
227 ret |= TIOCM_RNG;
228 if (status & UART_MSR_DSR)
229 ret |= TIOCM_DSR;
230 if (status & UART_MSR_CTS)
231 ret |= TIOCM_CTS;
232 return ret;
233}
234
1e04b7ae
TLSC		 235static void sdio_uart_write_mctrl(struct sdio_uart_port *port,
236 unsigned int mctrl)
6e418a9d
NP		 237{
238 unsigned char mcr = 0;
239
240 if (mctrl & TIOCM_RTS)
241 mcr |= UART_MCR_RTS;
242 if (mctrl & TIOCM_DTR)
243 mcr |= UART_MCR_DTR;
244 if (mctrl & TIOCM_OUT1)
245 mcr |= UART_MCR_OUT1;
246 if (mctrl & TIOCM_OUT2)
247 mcr |= UART_MCR_OUT2;
248 if (mctrl & TIOCM_LOOP)
249 mcr |= UART_MCR_LOOP;
250
251 sdio_out(port, UART_MCR, mcr);
252}
253
254static inline void sdio_uart_update_mctrl(struct sdio_uart_port *port,
255 unsigned int set, unsigned int clear)
256{
257 unsigned int old;
258
259 old = port->mctrl;
260 port->mctrl = (old & ~clear) | set;
261 if (old != port->mctrl)
262 sdio_uart_write_mctrl(port, port->mctrl);
263}
264
265#define sdio_uart_set_mctrl(port, x) sdio_uart_update_mctrl(port, x, 0)
266#define sdio_uart_clear_mctrl(port, x) sdio_uart_update_mctrl(port, 0, x)
267
268static void sdio_uart_change_speed(struct sdio_uart_port *port,
269 struct ktermios *termios,
270 struct ktermios *old)
271{
272 unsigned char cval, fcr = 0;
273 unsigned int baud, quot;
274
275 switch (termios->c_cflag & CSIZE) {
276 case CS5:
277 cval = UART_LCR_WLEN5;
278 break;
279 case CS6:
280 cval = UART_LCR_WLEN6;
281 break;
282 case CS7:
283 cval = UART_LCR_WLEN7;
284 break;
285 default:
286 case CS8:
287 cval = UART_LCR_WLEN8;
288 break;
289 }
290
291 if (termios->c_cflag & CSTOPB)
292 cval |= UART_LCR_STOP;
293 if (termios->c_cflag & PARENB)
294 cval |= UART_LCR_PARITY;
295 if (!(termios->c_cflag & PARODD))
296 cval |= UART_LCR_EPAR;
297
298 for (;;) {
299 baud = tty_termios_baud_rate(termios);
300 if (baud == 0)
301 baud = 9600; /* Special case: B0 rate. */
302 if (baud <= port->uartclk)
303 break;
304 /*
305 * Oops, the quotient was zero. Try again with the old
306 * baud rate if possible, otherwise default to 9600.
307 */
308 termios->c_cflag &= ~CBAUD;
309 if (old) {
310 termios->c_cflag |= old->c_cflag & CBAUD;
311 old = NULL;
312 } else
313 termios->c_cflag |= B9600;
314 }
315 quot = (2 * port->uartclk + baud) / (2 * baud);
316
317 if (baud < 2400)
318 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_TRIGGER_1;
319 else
320 fcr = UART_FCR_ENABLE_FIFO | UART_FCR_R_TRIG_10;
321
322 port->read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
323 if (termios->c_iflag & INPCK)
324 port->read_status_mask |= UART_LSR_FE | UART_LSR_PE;
325 if (termios->c_iflag & (BRKINT | PARMRK))
326 port->read_status_mask |= UART_LSR_BI;
327
328 /*
329 * Characters to ignore
330 */
331 port->ignore_status_mask = 0;
332 if (termios->c_iflag & IGNPAR)
333 port->ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
334 if (termios->c_iflag & IGNBRK) {
335 port->ignore_status_mask |= UART_LSR_BI;
336 /*
337 * If we're ignoring parity and break indicators,
338 * ignore overruns too (for real raw support).
339 */
340 if (termios->c_iflag & IGNPAR)
341 port->ignore_status_mask |= UART_LSR_OE;
342 }
343
344 /*
345 * ignore all characters if CREAD is not set
346 */
347 if ((termios->c_cflag & CREAD) == 0)
348 port->ignore_status_mask |= UART_LSR_DR;
349
350 /*
351 * CTS flow control flag and modem status interrupts
352 */
353 port->ier &= ~UART_IER_MSI;
354 if ((termios->c_cflag & CRTSCTS) || !(termios->c_cflag & CLOCAL))
355 port->ier |= UART_IER_MSI;
356
357 port->lcr = cval;
358
359 sdio_out(port, UART_IER, port->ier);
360 sdio_out(port, UART_LCR, cval | UART_LCR_DLAB);
361 sdio_out(port, UART_DLL, quot & 0xff);
362 sdio_out(port, UART_DLM, quot >> 8);
363 sdio_out(port, UART_LCR, cval);
364 sdio_out(port, UART_FCR, fcr);
365
366 sdio_uart_write_mctrl(port, port->mctrl);
367}
368
369static void sdio_uart_start_tx(struct sdio_uart_port *port)
370{
371 if (!(port->ier & UART_IER_THRI)) {
372 port->ier |= UART_IER_THRI;
373 sdio_out(port, UART_IER, port->ier);
374 }
375}
376
377static void sdio_uart_stop_tx(struct sdio_uart_port *port)
378{
379 if (port->ier & UART_IER_THRI) {
380 port->ier &= ~UART_IER_THRI;
381 sdio_out(port, UART_IER, port->ier);
382 }
383}
384
385static void sdio_uart_stop_rx(struct sdio_uart_port *port)
386{
387 port->ier &= ~UART_IER_RLSI;
388 port->read_status_mask &= ~UART_LSR_DR;
389 sdio_out(port, UART_IER, port->ier);
390}
391
1e04b7ae
TLSC		 392static void sdio_uart_receive_chars(struct sdio_uart_port *port,
393 unsigned int *status)
6e418a9d 394{
b5849b1a 395 struct tty_struct *tty = port->port.tty;
6e418a9d
NP		 396 unsigned int ch, flag;
397 int max_count = 256;
398
399 do {
400 ch = sdio_in(port, UART_RX);
401 flag = TTY_NORMAL;
402 port->icount.rx++;
403
404 if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
1e04b7ae 405 UART_LSR_FE | UART_LSR_OE))) {
6e418a9d
NP		 406 /*
407 * For statistics only
408 */
409 if (*status & UART_LSR_BI) {
410 *status &= ~(UART_LSR_FE | UART_LSR_PE);
411 port->icount.brk++;
412 } else if (*status & UART_LSR_PE)
413 port->icount.parity++;
414 else if (*status & UART_LSR_FE)
415 port->icount.frame++;
416 if (*status & UART_LSR_OE)
417 port->icount.overrun++;
418
419 /*
420 * Mask off conditions which should be ignored.
421 */
422 *status &= port->read_status_mask;
1e04b7ae 423 if (*status & UART_LSR_BI)
6e418a9d 424 flag = TTY_BREAK;
1e04b7ae 425 else if (*status & UART_LSR_PE)
6e418a9d
NP		 426 flag = TTY_PARITY;
427 else if (*status & UART_LSR_FE)
428 flag = TTY_FRAME;
429 }
430
431 if ((*status & port->ignore_status_mask & ~UART_LSR_OE) == 0)
432 tty_insert_flip_char(tty, ch, flag);
433
434 /*
435 * Overrun is special. Since it's reported immediately,
436 * it doesn't affect the current character.
437 */
438 if (*status & ~port->ignore_status_mask & UART_LSR_OE)
439 tty_insert_flip_char(tty, 0, TTY_OVERRUN);
440
441 *status = sdio_in(port, UART_LSR);
442 } while ((*status & UART_LSR_DR) && (max_count-- > 0));
443 tty_flip_buffer_push(tty);
444}
445
446static void sdio_uart_transmit_chars(struct sdio_uart_port *port)
447{
448 struct circ_buf *xmit = &port->xmit;
449 int count;
b5849b1a 450 struct tty_struct *tty = port->port.tty;
6e418a9d
NP		 451
452 if (port->x_char) {
453 sdio_out(port, UART_TX, port->x_char);
454 port->icount.tx++;
455 port->x_char = 0;
456 return;
457 }
b5849b1a 458 if (circ_empty(xmit) || tty->stopped || tty->hw_stopped) {
6e418a9d
NP		 459 sdio_uart_stop_tx(port);
460 return;
461 }
462
463 count = 16;
464 do {
465 sdio_out(port, UART_TX, xmit->buf[xmit->tail]);
466 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
467 port->icount.tx++;
468 if (circ_empty(xmit))
469 break;
470 } while (--count > 0);
471
472 if (circ_chars_pending(xmit) < WAKEUP_CHARS)
b5849b1a 473 tty_wakeup(tty);
6e418a9d
NP		 474
475 if (circ_empty(xmit))
476 sdio_uart_stop_tx(port);
477}
478
479static void sdio_uart_check_modem_status(struct sdio_uart_port *port)
480{
481 int status;
b5849b1a 482 struct tty_struct *tty = port->port.tty;
6e418a9d
NP		 483
484 status = sdio_in(port, UART_MSR);
485
486 if ((status & UART_MSR_ANY_DELTA) == 0)
487 return;
488
489 if (status & UART_MSR_TERI)
490 port->icount.rng++;
491 if (status & UART_MSR_DDSR)
492 port->icount.dsr++;
493 if (status & UART_MSR_DDCD)
494 port->icount.dcd++;
495 if (status & UART_MSR_DCTS) {
496 port->icount.cts++;
b5849b1a 497 if (tty->termios->c_cflag & CRTSCTS) {
6e418a9d 498 int cts = (status & UART_MSR_CTS);
b5849b1a 499 if (tty->hw_stopped) {
6e418a9d 500 if (cts) {
b5849b1a 501 tty->hw_stopped = 0;
6e418a9d 502 sdio_uart_start_tx(port);
b5849b1a 503 tty_wakeup(tty);
6e418a9d
NP		 504 }
505 } else {
506 if (!cts) {
b5849b1a 507 tty->hw_stopped = 1;
6e418a9d
NP		 508 sdio_uart_stop_tx(port);
509 }
510 }
511 }
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
548static int sdio_uart_startup(struct sdio_uart_port *port)
549{
550 unsigned long page;
551 int ret;
b5849b1a 552 struct tty_struct *tty = port->port.tty;
6e418a9d
NP		 553
554 /*
555 * Set the TTY IO error marker - we will only clear this
556 * once we have successfully opened the port.
557 */
b5849b1a 558 set_bit(TTY_IO_ERROR, &tty->flags);
6e418a9d
NP		 559
560 /* Initialise and allocate the transmit buffer. */
561 page = __get_free_page(GFP_KERNEL);
562 if (!page)
563 return -ENOMEM;
564 port->xmit.buf = (unsigned char *)page;
565 circ_clear(&port->xmit);
566
567 ret = sdio_uart_claim_func(port);
568 if (ret)
569 goto err1;
570 ret = sdio_enable_func(port->func);
571 if (ret)
572 goto err2;
573 ret = sdio_claim_irq(port->func, sdio_uart_irq);
574 if (ret)
575 goto err3;
576
577 /*
578 * Clear the FIFO buffers and disable them.
579 * (they will be reenabled in sdio_change_speed())
580 */
581 sdio_out(port, UART_FCR, UART_FCR_ENABLE_FIFO);
582 sdio_out(port, UART_FCR, UART_FCR_ENABLE_FIFO |
1e04b7ae 583 UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
6e418a9d
NP		 584 sdio_out(port, UART_FCR, 0);
585
586 /*
587 * Clear the interrupt registers.
588 */
589 (void) sdio_in(port, UART_LSR);
590 (void) sdio_in(port, UART_RX);
591 (void) sdio_in(port, UART_IIR);
592 (void) sdio_in(port, UART_MSR);
593
594 /*
595 * Now, initialize the UART
596 */
597 sdio_out(port, UART_LCR, UART_LCR_WLEN8);
598
599 port->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE | UART_IER_UUE;
600 port->mctrl = TIOCM_OUT2;
601
b5849b1a 602 sdio_uart_change_speed(port, tty->termios, NULL);
6e418a9d 603
b5849b1a 604 if (tty->termios->c_cflag & CBAUD)
6e418a9d
NP		 605 sdio_uart_set_mctrl(port, TIOCM_RTS | TIOCM_DTR);
606
b5849b1a 607 if (tty->termios->c_cflag & CRTSCTS)
6e418a9d 608 if (!(sdio_uart_get_mctrl(port) & TIOCM_CTS))
b5849b1a 609 tty->hw_stopped = 1;
6e418a9d
NP		 610
611 clear_bit(TTY_IO_ERROR, &port->tty->flags);
612
613 /* Kick the IRQ handler once while we're still holding the host lock */
614 sdio_uart_irq(port->func);
615
616 sdio_uart_release_func(port);
617 return 0;
618
619err3:
620 sdio_disable_func(port->func);
621err2:
622 sdio_uart_release_func(port);
623err1:
624 free_page((unsigned long)port->xmit.buf);
625 return ret;
626}
627
628static void sdio_uart_shutdown(struct sdio_uart_port *port)
629{
630 int ret;
631
632 ret = sdio_uart_claim_func(port);
633 if (ret)
634 goto skip;
635
636 sdio_uart_stop_rx(port);
637
638 /* TODO: wait here for TX FIFO to drain */
639
640 /* Turn off DTR and RTS early. */
b5849b1a 641 if (port->port.tty->termios->c_cflag & HUPCL)
6e418a9d
NP		 642 sdio_uart_clear_mctrl(port, TIOCM_DTR | TIOCM_RTS);
643
1e04b7ae 644 /* Disable interrupts from this port */
6e418a9d
NP		 645 sdio_release_irq(port->func);
646 port->ier = 0;
647 sdio_out(port, UART_IER, 0);
648
649 sdio_uart_clear_mctrl(port, TIOCM_OUT2);
650
651 /* Disable break condition and FIFOs. */
652 port->lcr &= ~UART_LCR_SBC;
653 sdio_out(port, UART_LCR, port->lcr);
654 sdio_out(port, UART_FCR, UART_FCR_ENABLE_FIFO |
655 UART_FCR_CLEAR_RCVR |
656 UART_FCR_CLEAR_XMIT);
657 sdio_out(port, UART_FCR, 0);
658
659 sdio_disable_func(port->func);
660
661 sdio_uart_release_func(port);
662
663skip:
664 /* Free the transmit buffer page. */
665 free_page((unsigned long)port->xmit.buf);
666}
667
1e04b7ae 668static int sdio_uart_open(struct tty_struct *tty, struct file *filp)
6e418a9d
NP		 669{
670 struct sdio_uart_port *port;
671 int ret;
672
673 port = sdio_uart_port_get(tty->index);
674 if (!port)
675 return -ENODEV;
676
677 mutex_lock(&port->open_lock);
678
679 /*
680 * Make sure not to mess up with a dead port
681 * which has not been closed yet.
682 */
683 if (tty->driver_data && tty->driver_data != port) {
684 mutex_unlock(&port->open_lock);
685 sdio_uart_port_put(port);
686 return -EBUSY;
687 }
688
689 if (!port->opened) {
690 tty->driver_data = port;
b5849b1a 691 port->port.tty = tty;
6e418a9d
NP		 692 ret = sdio_uart_startup(port);
693 if (ret) {
694 tty->driver_data = NULL;
b5849b1a 695 port->port.tty = NULL;
6e418a9d
NP		 696 mutex_unlock(&port->open_lock);
697 sdio_uart_port_put(port);
698 return ret;
699 }
700 }
701 port->opened++;
702 mutex_unlock(&port->open_lock);
703 return 0;
704}
705
706static void sdio_uart_close(struct tty_struct *tty, struct file * filp)
707{
708 struct sdio_uart_port *port = tty->driver_data;
709
710 if (!port)
711 return;
712
713 mutex_lock(&port->open_lock);
714 BUG_ON(!port->opened);
715
716 /*
717 * This is messy. The tty layer calls us even when open()
718 * returned an error. Ignore this close request if tty->count
719 * is larger than port->count.
720 */
721 if (tty->count > port->opened) {
722 mutex_unlock(&port->open_lock);
723 return;
724 }
725
726 if (--port->opened == 0) {
727 tty->closing = 1;
728 sdio_uart_shutdown(port);
729 tty_ldisc_flush(tty);
b5849b1a 730 port->port.tty = NULL;
6e418a9d
NP		 731 tty->driver_data = NULL;
732 tty->closing = 0;
733 }
734 mutex_unlock(&port->open_lock);
735 sdio_uart_port_put(port);
736}
737
738static int sdio_uart_write(struct tty_struct * tty, const unsigned char *buf,
739 int count)
740{
741 struct sdio_uart_port *port = tty->driver_data;
742 struct circ_buf *circ = &port->xmit;
743 int c, ret = 0;
744
745 if (!port->func)
746 return -ENODEV;
747
748 spin_lock(&port->write_lock);
749 while (1) {
750 c = CIRC_SPACE_TO_END(circ->head, circ->tail, UART_XMIT_SIZE);
751 if (count < c)
752 c = count;
753 if (c <= 0)
754 break;
755 memcpy(circ->buf + circ->head, buf, c);
756 circ->head = (circ->head + c) & (UART_XMIT_SIZE - 1);
757 buf += c;
758 count -= c;
759 ret += c;
760 }
761 spin_unlock(&port->write_lock);
762
763 if ( !(port->ier & UART_IER_THRI)) {
764 int err = sdio_uart_claim_func(port);
765 if (!err) {
766 sdio_uart_start_tx(port);
767 sdio_uart_irq(port->func);
768 sdio_uart_release_func(port);
769 } else
770 ret = err;
771 }
772
773 return ret;
774}
775
776static int sdio_uart_write_room(struct tty_struct *tty)
777{
778 struct sdio_uart_port *port = tty->driver_data;
779 return port ? circ_chars_free(&port->xmit) : 0;
780}
781
782static int sdio_uart_chars_in_buffer(struct tty_struct *tty)
783{
784 struct sdio_uart_port *port = tty->driver_data;
785 return port ? circ_chars_pending(&port->xmit) : 0;
786}
787
788static void sdio_uart_send_xchar(struct tty_struct *tty, char ch)
789{
790 struct sdio_uart_port *port = tty->driver_data;
791
792 port->x_char = ch;
793 if (ch && !(port->ier & UART_IER_THRI)) {
794 if (sdio_uart_claim_func(port) != 0)
795 return;
796 sdio_uart_start_tx(port);
797 sdio_uart_irq(port->func);
798 sdio_uart_release_func(port);
799 }
800}
801
802static void sdio_uart_throttle(struct tty_struct *tty)
803{
804 struct sdio_uart_port *port = tty->driver_data;
805
806 if (!I_IXOFF(tty) && !(tty->termios->c_cflag & CRTSCTS))
807 return;
808
809 if (sdio_uart_claim_func(port) != 0)
810 return;
811
812 if (I_IXOFF(tty)) {
813 port->x_char = STOP_CHAR(tty);
814 sdio_uart_start_tx(port);
815 }
816
817 if (tty->termios->c_cflag & CRTSCTS)
818 sdio_uart_clear_mctrl(port, TIOCM_RTS);
819
820 sdio_uart_irq(port->func);
821 sdio_uart_release_func(port);
822}
823
824static void sdio_uart_unthrottle(struct tty_struct *tty)
825{
826 struct sdio_uart_port *port = tty->driver_data;
827
828 if (!I_IXOFF(tty) && !(tty->termios->c_cflag & CRTSCTS))
829 return;
830
831 if (sdio_uart_claim_func(port) != 0)
832 return;
833
834 if (I_IXOFF(tty)) {
835 if (port->x_char) {
836 port->x_char = 0;
837 } else {
838 port->x_char = START_CHAR(tty);
839 sdio_uart_start_tx(port);
840 }
841 }
842
843 if (tty->termios->c_cflag & CRTSCTS)
844 sdio_uart_set_mctrl(port, TIOCM_RTS);
845
846 sdio_uart_irq(port->func);
847 sdio_uart_release_func(port);
848}
849
850static void sdio_uart_set_termios(struct tty_struct *tty, struct ktermios *old_termios)
851{
852 struct sdio_uart_port *port = tty->driver_data;
853 unsigned int cflag = tty->termios->c_cflag;
854
1e04b7ae 855#define RELEVANT_IFLAG(iflag) ((iflag) & (IGNBRK|BRKINT|IGNPAR|PARMRK|INPCK))
6e418a9d
NP		 856
857 if ((cflag ^ old_termios->c_cflag) == 0 &&
858 RELEVANT_IFLAG(tty->termios->c_iflag ^ old_termios->c_iflag) == 0)
859 return;
860
861 if (sdio_uart_claim_func(port) != 0)
862 return;
863
864 sdio_uart_change_speed(port, tty->termios, old_termios);
865
866 /* Handle transition to B0 status */
867 if ((old_termios->c_cflag & CBAUD) && !(cflag & CBAUD))
868 sdio_uart_clear_mctrl(port, TIOCM_RTS | TIOCM_DTR);
869
870 /* Handle transition away from B0 status */
871 if (!(old_termios->c_cflag & CBAUD) && (cflag & CBAUD)) {
872 unsigned int mask = TIOCM_DTR;
873 if (!(cflag & CRTSCTS) || !test_bit(TTY_THROTTLED, &tty->flags))
874 mask |= TIOCM_RTS;
875 sdio_uart_set_mctrl(port, mask);
876 }
877
878 /* Handle turning off CRTSCTS */
879 if ((old_termios->c_cflag & CRTSCTS) && !(cflag & CRTSCTS)) {
880 tty->hw_stopped = 0;
881 sdio_uart_start_tx(port);
882 }
883
884 /* Handle turning on CRTSCTS */
885 if (!(old_termios->c_cflag & CRTSCTS) && (cflag & CRTSCTS)) {
886 if (!(sdio_uart_get_mctrl(port) & TIOCM_CTS)) {
887 tty->hw_stopped = 1;
888 sdio_uart_stop_tx(port);
889 }
890 }
891
892 sdio_uart_release_func(port);
893}
894
c43d8636 895static int sdio_uart_break_ctl(struct tty_struct *tty, int break_state)
6e418a9d
NP		 896{
897 struct sdio_uart_port *port = tty->driver_data;
c43d8636 898 int result;
6e418a9d 899
c43d8636
DH		 900 result = sdio_uart_claim_func(port);
901 if (result != 0)
902 return result;
6e418a9d
NP		 903
904 if (break_state == -1)
905 port->lcr |= UART_LCR_SBC;
906 else
907 port->lcr &= ~UART_LCR_SBC;
908 sdio_out(port, UART_LCR, port->lcr);
909
910 sdio_uart_release_func(port);
c43d8636 911 return 0;
6e418a9d
NP		 912}
913
914static int sdio_uart_tiocmget(struct tty_struct *tty, struct file *file)
915{
916 struct sdio_uart_port *port = tty->driver_data;
917 int result;
918
919 result = sdio_uart_claim_func(port);
920 if (!result) {
921 result = port->mctrl | sdio_uart_get_mctrl(port);
922 sdio_uart_release_func(port);
923 }
924
925 return result;
926}
927
928static int sdio_uart_tiocmset(struct tty_struct *tty, struct file *file,
929 unsigned int set, unsigned int clear)
930{
931 struct sdio_uart_port *port = tty->driver_data;
932 int result;
933
1e04b7ae 934 result = sdio_uart_claim_func(port);
6e418a9d
NP		 935 if(!result) {
936 sdio_uart_update_mctrl(port, set, clear);
937 sdio_uart_release_func(port);
938 }
939
940 return result;
941}
942
201a50ba 943static int sdio_uart_proc_show(struct seq_file *m, void *v)
5ed334a1 944{
201a50ba 945 int i;
5ed334a1 946
201a50ba 947 seq_printf(m, "serinfo:1.0 driver%s%s revision:%s\n",
5ed334a1 948 "", "", "");
201a50ba 949 for (i = 0; i < UART_NR; i++) {
5ed334a1
NP		 950 struct sdio_uart_port *port = sdio_uart_port_get(i);
951 if (port) {
201a50ba 952 seq_printf(m, "%d: uart:SDIO", i);
5ed334a1 953 if(capable(CAP_SYS_ADMIN)) {
201a50ba 954 seq_printf(m, " tx:%d rx:%d",
1e04b7ae 955 port->icount.tx, port->icount.rx);
5ed334a1 956 if (port->icount.frame)
201a50ba 957 seq_printf(m, " fe:%d",
1e04b7ae 958 port->icount.frame);
5ed334a1 959 if (port->icount.parity)
201a50ba 960 seq_printf(m, " pe:%d",
1e04b7ae 961 port->icount.parity);
5ed334a1 962 if (port->icount.brk)
201a50ba 963 seq_printf(m, " brk:%d",
1e04b7ae 964 port->icount.brk);
5ed334a1 965 if (port->icount.overrun)
201a50ba 966 seq_printf(m, " oe:%d",
1e04b7ae 967 port->icount.overrun);
5ed334a1 968 if (port->icount.cts)
201a50ba 969 seq_printf(m, " cts:%d",
1e04b7ae 970 port->icount.cts);
5ed334a1 971 if (port->icount.dsr)
201a50ba 972 seq_printf(m, " dsr:%d",
1e04b7ae 973 port->icount.dsr);
5ed334a1 974 if (port->icount.rng)
201a50ba 975 seq_printf(m, " rng:%d",
1e04b7ae 976 port->icount.rng);
5ed334a1 977 if (port->icount.dcd)
201a50ba 978 seq_printf(m, " dcd:%d",
1e04b7ae 979 port->icount.dcd);
5ed334a1 980 }
5ed334a1 981 sdio_uart_port_put(port);
201a50ba 982 seq_putc(m, '\n');
5ed334a1
NP		 983 }
984 }
201a50ba
AD		 985 return 0;
986}
5ed334a1 987
201a50ba
AD		 988static int sdio_uart_proc_open(struct inode *inode, struct file *file)
989{
990 return single_open(file, sdio_uart_proc_show, NULL);
5ed334a1
NP		 991}
992
201a50ba
AD		 993static const struct file_operations sdio_uart_proc_fops = {
994 .owner = THIS_MODULE,
995 .open = sdio_uart_proc_open,
996 .read = seq_read,
997 .llseek = seq_lseek,
998 .release = single_release,
999};
1000
6e418a9d
NP		 1001static const struct tty_operations sdio_uart_ops = {
1002 .open = sdio_uart_open,
1003 .close = sdio_uart_close,
1004 .write = sdio_uart_write,
1005 .write_room = sdio_uart_write_room,
1006 .chars_in_buffer = sdio_uart_chars_in_buffer,
1007 .send_xchar = sdio_uart_send_xchar,
1008 .throttle = sdio_uart_throttle,
1009 .unthrottle = sdio_uart_unthrottle,
1010 .set_termios = sdio_uart_set_termios,
1011 .break_ctl = sdio_uart_break_ctl,
1012 .tiocmget = sdio_uart_tiocmget,
1013 .tiocmset = sdio_uart_tiocmset,
201a50ba 1014 .proc_fops = &sdio_uart_proc_fops,
6e418a9d
NP		 1015};
1016
1017static struct tty_driver *sdio_uart_tty_driver;
1018
1019static int sdio_uart_probe(struct sdio_func *func,
1020 const struct sdio_device_id *id)
1021{
1022 struct sdio_uart_port *port;
1023 int ret;
1024
1025 port = kzalloc(sizeof(struct sdio_uart_port), GFP_KERNEL);
1026 if (!port)
1027 return -ENOMEM;
1028
1029 if (func->class == SDIO_CLASS_UART) {
1030 printk(KERN_WARNING "%s: need info on UART class basic setup\n",
1031 sdio_func_id(func));
1032 kfree(port);
1033 return -ENOSYS;
1034 } else if (func->class == SDIO_CLASS_GPS) {
1035 /*
1036 * We need tuple 0x91. It contains SUBTPL_SIOREG
1037 * and SUBTPL_RCVCAPS.
1038 */
1039 struct sdio_func_tuple *tpl;
1040 for (tpl = func->tuples; tpl; tpl = tpl->next) {
1041 if (tpl->code != 0x91)
1042 continue;
1043 if (tpl->size < 10)
1044 continue;
1045 if (tpl->data[1] == 0) /* SUBTPL_SIOREG */
1046 break;
1047 }
1048 if (!tpl) {
1049 printk(KERN_WARNING
1050 "%s: can't find tuple 0x91 subtuple 0 (SUBTPL_SIOREG) for GPS class\n",
1051 sdio_func_id(func));
1052 kfree(port);
1053 return -EINVAL;
1054 }
1055 printk(KERN_DEBUG "%s: Register ID = 0x%02x, Exp ID = 0x%02x\n",
1056 sdio_func_id(func), tpl->data[2], tpl->data[3]);
1057 port->regs_offset = (tpl->data[4] << 0) |
1058 (tpl->data[5] << 8) |
1059 (tpl->data[6] << 16);
1060 printk(KERN_DEBUG "%s: regs offset = 0x%x\n",
1061 sdio_func_id(func), port->regs_offset);
1062 port->uartclk = tpl->data[7] * 115200;
1063 if (port->uartclk == 0)
1064 port->uartclk = 115200;
1065 printk(KERN_DEBUG "%s: clk %d baudcode %u 4800-div %u\n",
1066 sdio_func_id(func), port->uartclk,
1067 tpl->data[7], tpl->data[8] | (tpl->data[9] << 8));
1068 } else {
1069 kfree(port);
1070 return -EINVAL;
1071 }
1072
1073 port->func = func;
1074 sdio_set_drvdata(func, port);
b5849b1a 1075 tty_port_init(&port->port);
6e418a9d
NP		 1076
1077 ret = sdio_uart_add_port(port);
1078 if (ret) {
1079 kfree(port);
1080 } else {
1081 struct device *dev;
1082 dev = tty_register_device(sdio_uart_tty_driver, port->index, &func->dev);
1083 if (IS_ERR(dev)) {
1084 sdio_uart_port_remove(port);
1085 ret = PTR_ERR(dev);
1086 }
1087 }
1088
1089 return ret;
1090}
1091
1092static void sdio_uart_remove(struct sdio_func *func)
1093{
1094 struct sdio_uart_port *port = sdio_get_drvdata(func);
1095
1096 tty_unregister_device(sdio_uart_tty_driver, port->index);
1097 sdio_uart_port_remove(port);
1098}
1099
1100static const struct sdio_device_id sdio_uart_ids[] = {
1101 { SDIO_DEVICE_CLASS(SDIO_CLASS_UART) },
1102 { SDIO_DEVICE_CLASS(SDIO_CLASS_GPS) },
1103 { /* end: all zeroes */ },
1104};
1105
1106MODULE_DEVICE_TABLE(sdio, sdio_uart_ids);
1107
1108static struct sdio_driver sdio_uart_driver = {
1109 .probe = sdio_uart_probe,
1110 .remove = sdio_uart_remove,
1111 .name = "sdio_uart",
1112 .id_table = sdio_uart_ids,
1113};
1114
1115static int __init sdio_uart_init(void)
1116{
1117 int ret;
1118 struct tty_driver *tty_drv;
1119
1120 sdio_uart_tty_driver = tty_drv = alloc_tty_driver(UART_NR);
1121 if (!tty_drv)
1122 return -ENOMEM;
1123
1124 tty_drv->owner = THIS_MODULE;
1125 tty_drv->driver_name = "sdio_uart";
1126 tty_drv->name = "ttySDIO";
1127 tty_drv->major = 0; /* dynamically allocated */
1128 tty_drv->minor_start = 0;
1129 tty_drv->type = TTY_DRIVER_TYPE_SERIAL;
1130 tty_drv->subtype = SERIAL_TYPE_NORMAL;
1131 tty_drv->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
1132 tty_drv->init_termios = tty_std_termios;
1133 tty_drv->init_termios.c_cflag = B4800 | CS8 | CREAD | HUPCL | CLOCAL;
2ba30eed
NP		 1134 tty_drv->init_termios.c_ispeed = 4800;
1135 tty_drv->init_termios.c_ospeed = 4800;
6e418a9d
NP		 1136 tty_set_operations(tty_drv, &sdio_uart_ops);
1137
1138 ret = tty_register_driver(tty_drv);
1139 if (ret)
1140 goto err1;
1141
1142 ret = sdio_register_driver(&sdio_uart_driver);
1143 if (ret)
1144 goto err2;
1145
1146 return 0;
1147
1148err2:
1149 tty_unregister_driver(tty_drv);
1150err1:
1151 put_tty_driver(tty_drv);
1152 return ret;
1153}
1154
1155static void __exit sdio_uart_exit(void)
1156{
1157 sdio_unregister_driver(&sdio_uart_driver);
1158 tty_unregister_driver(sdio_uart_tty_driver);
1159 put_tty_driver(sdio_uart_tty_driver);
1160}
1161
1162module_init(sdio_uart_init);
1163module_exit(sdio_uart_exit);
1164
1165MODULE_AUTHOR("Nicolas Pitre");
1166MODULE_LICENSE("GPL");
Linux kernel - Deliverables
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