1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * Driver core for Samsung SoC onboard UARTs.
4 *
5 * Ben Dooks, Copyright (c) 2003-2008 Simtec Electronics
6 * http://armlinux.simtec.co.uk/
7 */
8
9 /* Hote on 2410 error handling
10 *
11 * The s3c2410 manual has a love/hate affair with the contents of the
12 * UERSTAT register in the UART blocks, and keeps marking some of the
13 * error bits as reserved. Having checked with the s3c2410x01,
14 * it copes with BREAKs properly, so I am happy to ignore the RESERVED
15 * feature from the latter versions of the manual.
16 *
17 * If it becomes aparrent that latter versions of the 2410 remove these
18 * bits, then action will have to be taken to differentiate the versions
19 * and change the policy on BREAK
20 *
21 * BJD, 04-Nov-2004
22 */
23
24 #if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
25 #define SUPPORT_SYSRQ
26 #endif
27
28 #include <linux/dmaengine.h>
29 #include <linux/dma-mapping.h>
30 #include <linux/slab.h>
31 #include <linux/module.h>
32 #include <linux/ioport.h>
33 #include <linux/io.h>
34 #include <linux/platform_device.h>
35 #include <linux/init.h>
36 #include <linux/sysrq.h>
37 #include <linux/console.h>
38 #include <linux/tty.h>
39 #include <linux/tty_flip.h>
40 #include <linux/serial_core.h>
41 #include <linux/serial.h>
42 #include <linux/serial_s3c.h>
43 #include <linux/delay.h>
44 #include <linux/clk.h>
45 #include <linux/cpufreq.h>
46 #include <linux/of.h>
47
48 #include <asm/irq.h>
49
50 #include "samsung.h"
51
52 #if defined(CONFIG_SERIAL_SAMSUNG_DEBUG) && \
53 !defined(MODULE)
54
55 extern void printascii(const char *);
56
57 __printf(1, 2)
dbg(const char * fmt,...)58 static void dbg(const char *fmt, ...)
59 {
60 va_list va;
61 char buff[256];
62
63 va_start(va, fmt);
64 vscnprintf(buff, sizeof(buff), fmt, va);
65 va_end(va);
66
67 printascii(buff);
68 }
69
70 #else
71 #define dbg(fmt, ...) do { if (0) no_printk(fmt, ##__VA_ARGS__); } while (0)
72 #endif
73
74 /* UART name and device definitions */
75
76 #define S3C24XX_SERIAL_NAME "ttySAC"
77 #define S3C24XX_SERIAL_MAJOR 204
78 #define S3C24XX_SERIAL_MINOR 64
79
80 #define S3C24XX_TX_PIO 1
81 #define S3C24XX_TX_DMA 2
82 #define S3C24XX_RX_PIO 1
83 #define S3C24XX_RX_DMA 2
84 /* macros to change one thing to another */
85
86 #define tx_enabled(port) ((port)->unused[0])
87 #define rx_enabled(port) ((port)->unused[1])
88
89 /* flag to ignore all characters coming in */
90 #define RXSTAT_DUMMY_READ (0x10000000)
91
to_ourport(struct uart_port * port)92 static inline struct s3c24xx_uart_port *to_ourport(struct uart_port *port)
93 {
94 return container_of(port, struct s3c24xx_uart_port, port);
95 }
96
97 /* translate a port to the device name */
98
s3c24xx_serial_portname(struct uart_port * port)99 static inline const char *s3c24xx_serial_portname(struct uart_port *port)
100 {
101 return to_platform_device(port->dev)->name;
102 }
103
s3c24xx_serial_txempty_nofifo(struct uart_port * port)104 static int s3c24xx_serial_txempty_nofifo(struct uart_port *port)
105 {
106 return rd_regl(port, S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXE;
107 }
108
109 /*
110 * s3c64xx and later SoC's include the interrupt mask and status registers in
111 * the controller itself, unlike the s3c24xx SoC's which have these registers
112 * in the interrupt controller. Check if the port type is s3c64xx or higher.
113 */
s3c24xx_serial_has_interrupt_mask(struct uart_port * port)114 static int s3c24xx_serial_has_interrupt_mask(struct uart_port *port)
115 {
116 return to_ourport(port)->info->type == PORT_S3C6400;
117 }
118
s3c24xx_serial_rx_enable(struct uart_port * port)119 static void s3c24xx_serial_rx_enable(struct uart_port *port)
120 {
121 unsigned long flags;
122 unsigned int ucon, ufcon;
123 int count = 10000;
124
125 spin_lock_irqsave(&port->lock, flags);
126
127 while (--count && !s3c24xx_serial_txempty_nofifo(port))
128 udelay(100);
129
130 ufcon = rd_regl(port, S3C2410_UFCON);
131 ufcon |= S3C2410_UFCON_RESETRX;
132 wr_regl(port, S3C2410_UFCON, ufcon);
133
134 ucon = rd_regl(port, S3C2410_UCON);
135 ucon |= S3C2410_UCON_RXIRQMODE;
136 wr_regl(port, S3C2410_UCON, ucon);
137
138 rx_enabled(port) = 1;
139 spin_unlock_irqrestore(&port->lock, flags);
140 }
141
s3c24xx_serial_rx_disable(struct uart_port * port)142 static void s3c24xx_serial_rx_disable(struct uart_port *port)
143 {
144 unsigned long flags;
145 unsigned int ucon;
146
147 spin_lock_irqsave(&port->lock, flags);
148
149 ucon = rd_regl(port, S3C2410_UCON);
150 ucon &= ~S3C2410_UCON_RXIRQMODE;
151 wr_regl(port, S3C2410_UCON, ucon);
152
153 rx_enabled(port) = 0;
154 spin_unlock_irqrestore(&port->lock, flags);
155 }
156
s3c24xx_serial_stop_tx(struct uart_port * port)157 static void s3c24xx_serial_stop_tx(struct uart_port *port)
158 {
159 struct s3c24xx_uart_port *ourport = to_ourport(port);
160 struct s3c24xx_uart_dma *dma = ourport->dma;
161 struct circ_buf *xmit = &port->state->xmit;
162 struct dma_tx_state state;
163 int count;
164
165 if (!tx_enabled(port))
166 return;
167
168 if (s3c24xx_serial_has_interrupt_mask(port))
169 s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM);
170 else
171 disable_irq_nosync(ourport->tx_irq);
172
173 if (dma && dma->tx_chan && ourport->tx_in_progress == S3C24XX_TX_DMA) {
174 dmaengine_pause(dma->tx_chan);
175 dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state);
176 dmaengine_terminate_all(dma->tx_chan);
177 dma_sync_single_for_cpu(ourport->port.dev,
178 dma->tx_transfer_addr, dma->tx_size, DMA_TO_DEVICE);
179 async_tx_ack(dma->tx_desc);
180 count = dma->tx_bytes_requested - state.residue;
181 xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1);
182 port->icount.tx += count;
183 }
184
185 tx_enabled(port) = 0;
186 ourport->tx_in_progress = 0;
187
188 if (port->flags & UPF_CONS_FLOW)
189 s3c24xx_serial_rx_enable(port);
190
191 ourport->tx_mode = 0;
192 }
193
194 static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport);
195
s3c24xx_serial_tx_dma_complete(void * args)196 static void s3c24xx_serial_tx_dma_complete(void *args)
197 {
198 struct s3c24xx_uart_port *ourport = args;
199 struct uart_port *port = &ourport->port;
200 struct circ_buf *xmit = &port->state->xmit;
201 struct s3c24xx_uart_dma *dma = ourport->dma;
202 struct dma_tx_state state;
203 unsigned long flags;
204 int count;
205
206
207 dmaengine_tx_status(dma->tx_chan, dma->tx_cookie, &state);
208 count = dma->tx_bytes_requested - state.residue;
209 async_tx_ack(dma->tx_desc);
210
211 dma_sync_single_for_cpu(ourport->port.dev, dma->tx_transfer_addr,
212 dma->tx_size, DMA_TO_DEVICE);
213
214 spin_lock_irqsave(&port->lock, flags);
215
216 xmit->tail = (xmit->tail + count) & (UART_XMIT_SIZE - 1);
217 port->icount.tx += count;
218 ourport->tx_in_progress = 0;
219
220 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
221 uart_write_wakeup(port);
222
223 s3c24xx_serial_start_next_tx(ourport);
224 spin_unlock_irqrestore(&port->lock, flags);
225 }
226
enable_tx_dma(struct s3c24xx_uart_port * ourport)227 static void enable_tx_dma(struct s3c24xx_uart_port *ourport)
228 {
229 struct uart_port *port = &ourport->port;
230 u32 ucon;
231
232 /* Mask Tx interrupt */
233 if (s3c24xx_serial_has_interrupt_mask(port))
234 s3c24xx_set_bit(port, S3C64XX_UINTM_TXD, S3C64XX_UINTM);
235 else
236 disable_irq_nosync(ourport->tx_irq);
237
238 /* Enable tx dma mode */
239 ucon = rd_regl(port, S3C2410_UCON);
240 ucon &= ~(S3C64XX_UCON_TXBURST_MASK | S3C64XX_UCON_TXMODE_MASK);
241 ucon |= (dma_get_cache_alignment() >= 16) ?
242 S3C64XX_UCON_TXBURST_16 : S3C64XX_UCON_TXBURST_1;
243 ucon |= S3C64XX_UCON_TXMODE_DMA;
244 wr_regl(port, S3C2410_UCON, ucon);
245
246 ourport->tx_mode = S3C24XX_TX_DMA;
247 }
248
enable_tx_pio(struct s3c24xx_uart_port * ourport)249 static void enable_tx_pio(struct s3c24xx_uart_port *ourport)
250 {
251 struct uart_port *port = &ourport->port;
252 u32 ucon, ufcon;
253
254 /* Set ufcon txtrig */
255 ourport->tx_in_progress = S3C24XX_TX_PIO;
256 ufcon = rd_regl(port, S3C2410_UFCON);
257 wr_regl(port, S3C2410_UFCON, ufcon);
258
259 /* Enable tx pio mode */
260 ucon = rd_regl(port, S3C2410_UCON);
261 ucon &= ~(S3C64XX_UCON_TXMODE_MASK);
262 ucon |= S3C64XX_UCON_TXMODE_CPU;
263 wr_regl(port, S3C2410_UCON, ucon);
264
265 /* Unmask Tx interrupt */
266 if (s3c24xx_serial_has_interrupt_mask(port))
267 s3c24xx_clear_bit(port, S3C64XX_UINTM_TXD,
268 S3C64XX_UINTM);
269 else
270 enable_irq(ourport->tx_irq);
271
272 ourport->tx_mode = S3C24XX_TX_PIO;
273 }
274
s3c24xx_serial_start_tx_pio(struct s3c24xx_uart_port * ourport)275 static void s3c24xx_serial_start_tx_pio(struct s3c24xx_uart_port *ourport)
276 {
277 if (ourport->tx_mode != S3C24XX_TX_PIO)
278 enable_tx_pio(ourport);
279 }
280
s3c24xx_serial_start_tx_dma(struct s3c24xx_uart_port * ourport,unsigned int count)281 static int s3c24xx_serial_start_tx_dma(struct s3c24xx_uart_port *ourport,
282 unsigned int count)
283 {
284 struct uart_port *port = &ourport->port;
285 struct circ_buf *xmit = &port->state->xmit;
286 struct s3c24xx_uart_dma *dma = ourport->dma;
287
288
289 if (ourport->tx_mode != S3C24XX_TX_DMA)
290 enable_tx_dma(ourport);
291
292 dma->tx_size = count & ~(dma_get_cache_alignment() - 1);
293 dma->tx_transfer_addr = dma->tx_addr + xmit->tail;
294
295 dma_sync_single_for_device(ourport->port.dev, dma->tx_transfer_addr,
296 dma->tx_size, DMA_TO_DEVICE);
297
298 dma->tx_desc = dmaengine_prep_slave_single(dma->tx_chan,
299 dma->tx_transfer_addr, dma->tx_size,
300 DMA_MEM_TO_DEV, DMA_PREP_INTERRUPT);
301 if (!dma->tx_desc) {
302 dev_err(ourport->port.dev, "Unable to get desc for Tx\n");
303 return -EIO;
304 }
305
306 dma->tx_desc->callback = s3c24xx_serial_tx_dma_complete;
307 dma->tx_desc->callback_param = ourport;
308 dma->tx_bytes_requested = dma->tx_size;
309
310 ourport->tx_in_progress = S3C24XX_TX_DMA;
311 dma->tx_cookie = dmaengine_submit(dma->tx_desc);
312 dma_async_issue_pending(dma->tx_chan);
313 return 0;
314 }
315
s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port * ourport)316 static void s3c24xx_serial_start_next_tx(struct s3c24xx_uart_port *ourport)
317 {
318 struct uart_port *port = &ourport->port;
319 struct circ_buf *xmit = &port->state->xmit;
320 unsigned long count;
321
322 /* Get data size up to the end of buffer */
323 count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
324
325 if (!count) {
326 s3c24xx_serial_stop_tx(port);
327 return;
328 }
329
330 if (!ourport->dma || !ourport->dma->tx_chan ||
331 count < ourport->min_dma_size ||
332 xmit->tail & (dma_get_cache_alignment() - 1))
333 s3c24xx_serial_start_tx_pio(ourport);
334 else
335 s3c24xx_serial_start_tx_dma(ourport, count);
336 }
337
s3c24xx_serial_start_tx(struct uart_port * port)338 static void s3c24xx_serial_start_tx(struct uart_port *port)
339 {
340 struct s3c24xx_uart_port *ourport = to_ourport(port);
341 struct circ_buf *xmit = &port->state->xmit;
342
343 if (!tx_enabled(port)) {
344 if (port->flags & UPF_CONS_FLOW)
345 s3c24xx_serial_rx_disable(port);
346
347 tx_enabled(port) = 1;
348 if (!ourport->dma || !ourport->dma->tx_chan)
349 s3c24xx_serial_start_tx_pio(ourport);
350 }
351
352 if (ourport->dma && ourport->dma->tx_chan) {
353 if (!uart_circ_empty(xmit) && !ourport->tx_in_progress)
354 s3c24xx_serial_start_next_tx(ourport);
355 }
356 }
357
s3c24xx_uart_copy_rx_to_tty(struct s3c24xx_uart_port * ourport,struct tty_port * tty,int count)358 static void s3c24xx_uart_copy_rx_to_tty(struct s3c24xx_uart_port *ourport,
359 struct tty_port *tty, int count)
360 {
361 struct s3c24xx_uart_dma *dma = ourport->dma;
362 int copied;
363
364 if (!count)
365 return;
366
367 dma_sync_single_for_cpu(ourport->port.dev, dma->rx_addr,
368 dma->rx_size, DMA_FROM_DEVICE);
369
370 ourport->port.icount.rx += count;
371 if (!tty) {
372 dev_err(ourport->port.dev, "No tty port\n");
373 return;
374 }
375 copied = tty_insert_flip_string(tty,
376 ((unsigned char *)(ourport->dma->rx_buf)), count);
377 if (copied != count) {
378 WARN_ON(1);
379 dev_err(ourport->port.dev, "RxData copy to tty layer failed\n");
380 }
381 }
382
s3c24xx_serial_stop_rx(struct uart_port * port)383 static void s3c24xx_serial_stop_rx(struct uart_port *port)
384 {
385 struct s3c24xx_uart_port *ourport = to_ourport(port);
386 struct s3c24xx_uart_dma *dma = ourport->dma;
387 struct tty_port *t = &port->state->port;
388 struct dma_tx_state state;
389 enum dma_status dma_status;
390 unsigned int received;
391
392 if (rx_enabled(port)) {
393 dbg("s3c24xx_serial_stop_rx: port=%p\n", port);
394 if (s3c24xx_serial_has_interrupt_mask(port))
395 s3c24xx_set_bit(port, S3C64XX_UINTM_RXD,
396 S3C64XX_UINTM);
397 else
398 disable_irq_nosync(ourport->rx_irq);
399 rx_enabled(port) = 0;
400 }
401 if (dma && dma->rx_chan) {
402 dmaengine_pause(dma->tx_chan);
403 dma_status = dmaengine_tx_status(dma->rx_chan,
404 dma->rx_cookie, &state);
405 if (dma_status == DMA_IN_PROGRESS ||
406 dma_status == DMA_PAUSED) {
407 received = dma->rx_bytes_requested - state.residue;
408 dmaengine_terminate_all(dma->rx_chan);
409 s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
410 }
411 }
412 }
413
414 static inline struct s3c24xx_uart_info
s3c24xx_port_to_info(struct uart_port * port)415 *s3c24xx_port_to_info(struct uart_port *port)
416 {
417 return to_ourport(port)->info;
418 }
419
420 static inline struct s3c2410_uartcfg
s3c24xx_port_to_cfg(struct uart_port * port)421 *s3c24xx_port_to_cfg(struct uart_port *port)
422 {
423 struct s3c24xx_uart_port *ourport;
424
425 if (port->dev == NULL)
426 return NULL;
427
428 ourport = container_of(port, struct s3c24xx_uart_port, port);
429 return ourport->cfg;
430 }
431
s3c24xx_serial_rx_fifocnt(struct s3c24xx_uart_port * ourport,unsigned long ufstat)432 static int s3c24xx_serial_rx_fifocnt(struct s3c24xx_uart_port *ourport,
433 unsigned long ufstat)
434 {
435 struct s3c24xx_uart_info *info = ourport->info;
436
437 if (ufstat & info->rx_fifofull)
438 return ourport->port.fifosize;
439
440 return (ufstat & info->rx_fifomask) >> info->rx_fifoshift;
441 }
442
443 static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport);
s3c24xx_serial_rx_dma_complete(void * args)444 static void s3c24xx_serial_rx_dma_complete(void *args)
445 {
446 struct s3c24xx_uart_port *ourport = args;
447 struct uart_port *port = &ourport->port;
448
449 struct s3c24xx_uart_dma *dma = ourport->dma;
450 struct tty_port *t = &port->state->port;
451 struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);
452
453 struct dma_tx_state state;
454 unsigned long flags;
455 int received;
456
457 dmaengine_tx_status(dma->rx_chan, dma->rx_cookie, &state);
458 received = dma->rx_bytes_requested - state.residue;
459 async_tx_ack(dma->rx_desc);
460
461 spin_lock_irqsave(&port->lock, flags);
462
463 if (received)
464 s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
465
466 if (tty) {
467 tty_flip_buffer_push(t);
468 tty_kref_put(tty);
469 }
470
471 s3c64xx_start_rx_dma(ourport);
472
473 spin_unlock_irqrestore(&port->lock, flags);
474 }
475
s3c64xx_start_rx_dma(struct s3c24xx_uart_port * ourport)476 static void s3c64xx_start_rx_dma(struct s3c24xx_uart_port *ourport)
477 {
478 struct s3c24xx_uart_dma *dma = ourport->dma;
479
480 dma_sync_single_for_device(ourport->port.dev, dma->rx_addr,
481 dma->rx_size, DMA_FROM_DEVICE);
482
483 dma->rx_desc = dmaengine_prep_slave_single(dma->rx_chan,
484 dma->rx_addr, dma->rx_size, DMA_DEV_TO_MEM,
485 DMA_PREP_INTERRUPT);
486 if (!dma->rx_desc) {
487 dev_err(ourport->port.dev, "Unable to get desc for Rx\n");
488 return;
489 }
490
491 dma->rx_desc->callback = s3c24xx_serial_rx_dma_complete;
492 dma->rx_desc->callback_param = ourport;
493 dma->rx_bytes_requested = dma->rx_size;
494
495 dma->rx_cookie = dmaengine_submit(dma->rx_desc);
496 dma_async_issue_pending(dma->rx_chan);
497 }
498
499 /* ? - where has parity gone?? */
500 #define S3C2410_UERSTAT_PARITY (0x1000)
501
enable_rx_dma(struct s3c24xx_uart_port * ourport)502 static void enable_rx_dma(struct s3c24xx_uart_port *ourport)
503 {
504 struct uart_port *port = &ourport->port;
505 unsigned int ucon;
506
507 /* set Rx mode to DMA mode */
508 ucon = rd_regl(port, S3C2410_UCON);
509 ucon &= ~(S3C64XX_UCON_RXBURST_MASK |
510 S3C64XX_UCON_TIMEOUT_MASK |
511 S3C64XX_UCON_EMPTYINT_EN |
512 S3C64XX_UCON_DMASUS_EN |
513 S3C64XX_UCON_TIMEOUT_EN |
514 S3C64XX_UCON_RXMODE_MASK);
515 ucon |= S3C64XX_UCON_RXBURST_16 |
516 0xf << S3C64XX_UCON_TIMEOUT_SHIFT |
517 S3C64XX_UCON_EMPTYINT_EN |
518 S3C64XX_UCON_TIMEOUT_EN |
519 S3C64XX_UCON_RXMODE_DMA;
520 wr_regl(port, S3C2410_UCON, ucon);
521
522 ourport->rx_mode = S3C24XX_RX_DMA;
523 }
524
enable_rx_pio(struct s3c24xx_uart_port * ourport)525 static void enable_rx_pio(struct s3c24xx_uart_port *ourport)
526 {
527 struct uart_port *port = &ourport->port;
528 unsigned int ucon;
529
530 /* set Rx mode to DMA mode */
531 ucon = rd_regl(port, S3C2410_UCON);
532 ucon &= ~(S3C64XX_UCON_TIMEOUT_MASK |
533 S3C64XX_UCON_EMPTYINT_EN |
534 S3C64XX_UCON_DMASUS_EN |
535 S3C64XX_UCON_TIMEOUT_EN |
536 S3C64XX_UCON_RXMODE_MASK);
537 ucon |= 0xf << S3C64XX_UCON_TIMEOUT_SHIFT |
538 S3C64XX_UCON_TIMEOUT_EN |
539 S3C64XX_UCON_RXMODE_CPU;
540 wr_regl(port, S3C2410_UCON, ucon);
541
542 ourport->rx_mode = S3C24XX_RX_PIO;
543 }
544
545 static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport);
546
s3c24xx_serial_rx_chars_dma(void * dev_id)547 static irqreturn_t s3c24xx_serial_rx_chars_dma(void *dev_id)
548 {
549 unsigned int utrstat, ufstat, received;
550 struct s3c24xx_uart_port *ourport = dev_id;
551 struct uart_port *port = &ourport->port;
552 struct s3c24xx_uart_dma *dma = ourport->dma;
553 struct tty_struct *tty = tty_port_tty_get(&ourport->port.state->port);
554 struct tty_port *t = &port->state->port;
555 unsigned long flags;
556 struct dma_tx_state state;
557
558 utrstat = rd_regl(port, S3C2410_UTRSTAT);
559 ufstat = rd_regl(port, S3C2410_UFSTAT);
560
561 spin_lock_irqsave(&port->lock, flags);
562
563 if (!(utrstat & S3C2410_UTRSTAT_TIMEOUT)) {
564 s3c64xx_start_rx_dma(ourport);
565 if (ourport->rx_mode == S3C24XX_RX_PIO)
566 enable_rx_dma(ourport);
567 goto finish;
568 }
569
570 if (ourport->rx_mode == S3C24XX_RX_DMA) {
571 dmaengine_pause(dma->rx_chan);
572 dmaengine_tx_status(dma->rx_chan, dma->rx_cookie, &state);
573 dmaengine_terminate_all(dma->rx_chan);
574 received = dma->rx_bytes_requested - state.residue;
575 s3c24xx_uart_copy_rx_to_tty(ourport, t, received);
576
577 enable_rx_pio(ourport);
578 }
579
580 s3c24xx_serial_rx_drain_fifo(ourport);
581
582 if (tty) {
583 tty_flip_buffer_push(t);
584 tty_kref_put(tty);
585 }
586
587 wr_regl(port, S3C2410_UTRSTAT, S3C2410_UTRSTAT_TIMEOUT);
588
589 finish:
590 spin_unlock_irqrestore(&port->lock, flags);
591
592 return IRQ_HANDLED;
593 }
594
s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port * ourport)595 static void s3c24xx_serial_rx_drain_fifo(struct s3c24xx_uart_port *ourport)
596 {
597 struct uart_port *port = &ourport->port;
598 unsigned int ufcon, ch, flag, ufstat, uerstat;
599 unsigned int fifocnt = 0;
600 int max_count = port->fifosize;
601
602 while (max_count-- > 0) {
603 /*
604 * Receive all characters known to be in FIFO
605 * before reading FIFO level again
606 */
607 if (fifocnt == 0) {
608 ufstat = rd_regl(port, S3C2410_UFSTAT);
609 fifocnt = s3c24xx_serial_rx_fifocnt(ourport, ufstat);
610 if (fifocnt == 0)
611 break;
612 }
613 fifocnt--;
614
615 uerstat = rd_regl(port, S3C2410_UERSTAT);
616 ch = rd_regb(port, S3C2410_URXH);
617
618 if (port->flags & UPF_CONS_FLOW) {
619 int txe = s3c24xx_serial_txempty_nofifo(port);
620
621 if (rx_enabled(port)) {
622 if (!txe) {
623 rx_enabled(port) = 0;
624 continue;
625 }
626 } else {
627 if (txe) {
628 ufcon = rd_regl(port, S3C2410_UFCON);
629 ufcon |= S3C2410_UFCON_RESETRX;
630 wr_regl(port, S3C2410_UFCON, ufcon);
631 rx_enabled(port) = 1;
632 return;
633 }
634 continue;
635 }
636 }
637
638 /* insert the character into the buffer */
639
640 flag = TTY_NORMAL;
641 port->icount.rx++;
642
643 if (unlikely(uerstat & S3C2410_UERSTAT_ANY)) {
644 dbg("rxerr: port ch=0x%02x, rxs=0x%08x\n",
645 ch, uerstat);
646
647 /* check for break */
648 if (uerstat & S3C2410_UERSTAT_BREAK) {
649 dbg("break!\n");
650 port->icount.brk++;
651 if (uart_handle_break(port))
652 continue; /* Ignore character */
653 }
654
655 if (uerstat & S3C2410_UERSTAT_FRAME)
656 port->icount.frame++;
657 if (uerstat & S3C2410_UERSTAT_OVERRUN)
658 port->icount.overrun++;
659
660 uerstat &= port->read_status_mask;
661
662 if (uerstat & S3C2410_UERSTAT_BREAK)
663 flag = TTY_BREAK;
664 else if (uerstat & S3C2410_UERSTAT_PARITY)
665 flag = TTY_PARITY;
666 else if (uerstat & (S3C2410_UERSTAT_FRAME |
667 S3C2410_UERSTAT_OVERRUN))
668 flag = TTY_FRAME;
669 }
670
671 if (uart_handle_sysrq_char(port, ch))
672 continue; /* Ignore character */
673
674 uart_insert_char(port, uerstat, S3C2410_UERSTAT_OVERRUN,
675 ch, flag);
676 }
677
678 tty_flip_buffer_push(&port->state->port);
679 }
680
s3c24xx_serial_rx_chars_pio(void * dev_id)681 static irqreturn_t s3c24xx_serial_rx_chars_pio(void *dev_id)
682 {
683 struct s3c24xx_uart_port *ourport = dev_id;
684 struct uart_port *port = &ourport->port;
685 unsigned long flags;
686
687 spin_lock_irqsave(&port->lock, flags);
688 s3c24xx_serial_rx_drain_fifo(ourport);
689 spin_unlock_irqrestore(&port->lock, flags);
690
691 return IRQ_HANDLED;
692 }
693
694
s3c24xx_serial_rx_chars(int irq,void * dev_id)695 static irqreturn_t s3c24xx_serial_rx_chars(int irq, void *dev_id)
696 {
697 struct s3c24xx_uart_port *ourport = dev_id;
698
699 if (ourport->dma && ourport->dma->rx_chan)
700 return s3c24xx_serial_rx_chars_dma(dev_id);
701 return s3c24xx_serial_rx_chars_pio(dev_id);
702 }
703
s3c24xx_serial_tx_chars(int irq,void * id)704 static irqreturn_t s3c24xx_serial_tx_chars(int irq, void *id)
705 {
706 struct s3c24xx_uart_port *ourport = id;
707 struct uart_port *port = &ourport->port;
708 struct circ_buf *xmit = &port->state->xmit;
709 unsigned long flags;
710 int count, dma_count = 0;
711
712 spin_lock_irqsave(&port->lock, flags);
713
714 count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
715
716 if (ourport->dma && ourport->dma->tx_chan &&
717 count >= ourport->min_dma_size) {
718 int align = dma_get_cache_alignment() -
719 (xmit->tail & (dma_get_cache_alignment() - 1));
720 if (count-align >= ourport->min_dma_size) {
721 dma_count = count-align;
722 count = align;
723 }
724 }
725
726 if (port->x_char) {
727 wr_regb(port, S3C2410_UTXH, port->x_char);
728 port->icount.tx++;
729 port->x_char = 0;
730 goto out;
731 }
732
733 /* if there isn't anything more to transmit, or the uart is now
734 * stopped, disable the uart and exit
735 */
736
737 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
738 s3c24xx_serial_stop_tx(port);
739 goto out;
740 }
741
742 /* try and drain the buffer... */
743
744 if (count > port->fifosize) {
745 count = port->fifosize;
746 dma_count = 0;
747 }
748
749 while (!uart_circ_empty(xmit) && count > 0) {
750 if (rd_regl(port, S3C2410_UFSTAT) & ourport->info->tx_fifofull)
751 break;
752
753 wr_regb(port, S3C2410_UTXH, xmit->buf[xmit->tail]);
754 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
755 port->icount.tx++;
756 count--;
757 }
758
759 if (!count && dma_count) {
760 s3c24xx_serial_start_tx_dma(ourport, dma_count);
761 goto out;
762 }
763
764 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) {
765 spin_unlock(&port->lock);
766 uart_write_wakeup(port);
767 spin_lock(&port->lock);
768 }
769
770 if (uart_circ_empty(xmit))
771 s3c24xx_serial_stop_tx(port);
772
773 out:
774 spin_unlock_irqrestore(&port->lock, flags);
775 return IRQ_HANDLED;
776 }
777
778 /* interrupt handler for s3c64xx and later SoC's.*/
s3c64xx_serial_handle_irq(int irq,void * id)779 static irqreturn_t s3c64xx_serial_handle_irq(int irq, void *id)
780 {
781 struct s3c24xx_uart_port *ourport = id;
782 struct uart_port *port = &ourport->port;
783 unsigned int pend = rd_regl(port, S3C64XX_UINTP);
784 irqreturn_t ret = IRQ_HANDLED;
785
786 if (pend & S3C64XX_UINTM_RXD_MSK) {
787 ret = s3c24xx_serial_rx_chars(irq, id);
788 wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_RXD_MSK);
789 }
790 if (pend & S3C64XX_UINTM_TXD_MSK) {
791 ret = s3c24xx_serial_tx_chars(irq, id);
792 wr_regl(port, S3C64XX_UINTP, S3C64XX_UINTM_TXD_MSK);
793 }
794 return ret;
795 }
796
s3c24xx_serial_tx_empty(struct uart_port * port)797 static unsigned int s3c24xx_serial_tx_empty(struct uart_port *port)
798 {
799 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
800 unsigned long ufstat = rd_regl(port, S3C2410_UFSTAT);
801 unsigned long ufcon = rd_regl(port, S3C2410_UFCON);
802
803 if (ufcon & S3C2410_UFCON_FIFOMODE) {
804 if ((ufstat & info->tx_fifomask) != 0 ||
805 (ufstat & info->tx_fifofull))
806 return 0;
807
808 return 1;
809 }
810
811 return s3c24xx_serial_txempty_nofifo(port);
812 }
813
814 /* no modem control lines */
s3c24xx_serial_get_mctrl(struct uart_port * port)815 static unsigned int s3c24xx_serial_get_mctrl(struct uart_port *port)
816 {
817 unsigned int umstat = rd_regb(port, S3C2410_UMSTAT);
818
819 if (umstat & S3C2410_UMSTAT_CTS)
820 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
821 else
822 return TIOCM_CAR | TIOCM_DSR;
823 }
824
s3c24xx_serial_set_mctrl(struct uart_port * port,unsigned int mctrl)825 static void s3c24xx_serial_set_mctrl(struct uart_port *port, unsigned int mctrl)
826 {
827 unsigned int umcon = rd_regl(port, S3C2410_UMCON);
828
829 if (mctrl & TIOCM_RTS)
830 umcon |= S3C2410_UMCOM_RTS_LOW;
831 else
832 umcon &= ~S3C2410_UMCOM_RTS_LOW;
833
834 wr_regl(port, S3C2410_UMCON, umcon);
835 }
836
s3c24xx_serial_break_ctl(struct uart_port * port,int break_state)837 static void s3c24xx_serial_break_ctl(struct uart_port *port, int break_state)
838 {
839 unsigned long flags;
840 unsigned int ucon;
841
842 spin_lock_irqsave(&port->lock, flags);
843
844 ucon = rd_regl(port, S3C2410_UCON);
845
846 if (break_state)
847 ucon |= S3C2410_UCON_SBREAK;
848 else
849 ucon &= ~S3C2410_UCON_SBREAK;
850
851 wr_regl(port, S3C2410_UCON, ucon);
852
853 spin_unlock_irqrestore(&port->lock, flags);
854 }
855
s3c24xx_serial_request_dma(struct s3c24xx_uart_port * p)856 static int s3c24xx_serial_request_dma(struct s3c24xx_uart_port *p)
857 {
858 struct s3c24xx_uart_dma *dma = p->dma;
859 struct dma_slave_caps dma_caps;
860 const char *reason = NULL;
861 int ret;
862
863 /* Default slave configuration parameters */
864 dma->rx_conf.direction = DMA_DEV_TO_MEM;
865 dma->rx_conf.src_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
866 dma->rx_conf.src_addr = p->port.mapbase + S3C2410_URXH;
867 dma->rx_conf.src_maxburst = 1;
868
869 dma->tx_conf.direction = DMA_MEM_TO_DEV;
870 dma->tx_conf.dst_addr_width = DMA_SLAVE_BUSWIDTH_1_BYTE;
871 dma->tx_conf.dst_addr = p->port.mapbase + S3C2410_UTXH;
872 dma->tx_conf.dst_maxburst = 1;
873
874 dma->rx_chan = dma_request_chan(p->port.dev, "rx");
875
876 if (IS_ERR(dma->rx_chan)) {
877 reason = "DMA RX channel request failed";
878 ret = PTR_ERR(dma->rx_chan);
879 goto err_warn;
880 }
881
882 ret = dma_get_slave_caps(dma->rx_chan, &dma_caps);
883 if (ret < 0 ||
884 dma_caps.residue_granularity < DMA_RESIDUE_GRANULARITY_BURST) {
885 reason = "insufficient DMA RX engine capabilities";
886 ret = -EOPNOTSUPP;
887 goto err_release_rx;
888 }
889
890 dmaengine_slave_config(dma->rx_chan, &dma->rx_conf);
891
892 dma->tx_chan = dma_request_chan(p->port.dev, "tx");
893 if (IS_ERR(dma->tx_chan)) {
894 reason = "DMA TX channel request failed";
895 ret = PTR_ERR(dma->tx_chan);
896 goto err_release_rx;
897 }
898
899 ret = dma_get_slave_caps(dma->tx_chan, &dma_caps);
900 if (ret < 0 ||
901 dma_caps.residue_granularity < DMA_RESIDUE_GRANULARITY_BURST) {
902 reason = "insufficient DMA TX engine capabilities";
903 ret = -EOPNOTSUPP;
904 goto err_release_tx;
905 }
906
907 dmaengine_slave_config(dma->tx_chan, &dma->tx_conf);
908
909 /* RX buffer */
910 dma->rx_size = PAGE_SIZE;
911
912 dma->rx_buf = kmalloc(dma->rx_size, GFP_KERNEL);
913 if (!dma->rx_buf) {
914 ret = -ENOMEM;
915 goto err_release_tx;
916 }
917
918 dma->rx_addr = dma_map_single(p->port.dev, dma->rx_buf,
919 dma->rx_size, DMA_FROM_DEVICE);
920 if (dma_mapping_error(p->port.dev, dma->rx_addr)) {
921 reason = "DMA mapping error for RX buffer";
922 ret = -EIO;
923 goto err_free_rx;
924 }
925
926 /* TX buffer */
927 dma->tx_addr = dma_map_single(p->port.dev, p->port.state->xmit.buf,
928 UART_XMIT_SIZE, DMA_TO_DEVICE);
929 if (dma_mapping_error(p->port.dev, dma->tx_addr)) {
930 reason = "DMA mapping error for TX buffer";
931 ret = -EIO;
932 goto err_unmap_rx;
933 }
934
935 return 0;
936
937 err_unmap_rx:
938 dma_unmap_single(p->port.dev, dma->rx_addr, dma->rx_size,
939 DMA_FROM_DEVICE);
940 err_free_rx:
941 kfree(dma->rx_buf);
942 err_release_tx:
943 dma_release_channel(dma->tx_chan);
944 err_release_rx:
945 dma_release_channel(dma->rx_chan);
946 err_warn:
947 if (reason)
948 dev_warn(p->port.dev, "%s, DMA will not be used\n", reason);
949 return ret;
950 }
951
s3c24xx_serial_release_dma(struct s3c24xx_uart_port * p)952 static void s3c24xx_serial_release_dma(struct s3c24xx_uart_port *p)
953 {
954 struct s3c24xx_uart_dma *dma = p->dma;
955
956 if (dma->rx_chan) {
957 dmaengine_terminate_all(dma->rx_chan);
958 dma_unmap_single(p->port.dev, dma->rx_addr,
959 dma->rx_size, DMA_FROM_DEVICE);
960 kfree(dma->rx_buf);
961 dma_release_channel(dma->rx_chan);
962 dma->rx_chan = NULL;
963 }
964
965 if (dma->tx_chan) {
966 dmaengine_terminate_all(dma->tx_chan);
967 dma_unmap_single(p->port.dev, dma->tx_addr,
968 UART_XMIT_SIZE, DMA_TO_DEVICE);
969 dma_release_channel(dma->tx_chan);
970 dma->tx_chan = NULL;
971 }
972 }
973
s3c24xx_serial_shutdown(struct uart_port * port)974 static void s3c24xx_serial_shutdown(struct uart_port *port)
975 {
976 struct s3c24xx_uart_port *ourport = to_ourport(port);
977
978 if (ourport->tx_claimed) {
979 if (!s3c24xx_serial_has_interrupt_mask(port))
980 free_irq(ourport->tx_irq, ourport);
981 tx_enabled(port) = 0;
982 ourport->tx_claimed = 0;
983 ourport->tx_mode = 0;
984 }
985
986 if (ourport->rx_claimed) {
987 if (!s3c24xx_serial_has_interrupt_mask(port))
988 free_irq(ourport->rx_irq, ourport);
989 ourport->rx_claimed = 0;
990 rx_enabled(port) = 0;
991 }
992
993 /* Clear pending interrupts and mask all interrupts */
994 if (s3c24xx_serial_has_interrupt_mask(port)) {
995 free_irq(port->irq, ourport);
996
997 wr_regl(port, S3C64XX_UINTP, 0xf);
998 wr_regl(port, S3C64XX_UINTM, 0xf);
999 }
1000
1001 if (ourport->dma)
1002 s3c24xx_serial_release_dma(ourport);
1003
1004 ourport->tx_in_progress = 0;
1005 }
1006
s3c24xx_serial_startup(struct uart_port * port)1007 static int s3c24xx_serial_startup(struct uart_port *port)
1008 {
1009 struct s3c24xx_uart_port *ourport = to_ourport(port);
1010 int ret;
1011
1012 dbg("s3c24xx_serial_startup: port=%p (%08llx,%p)\n",
1013 port, (unsigned long long)port->mapbase, port->membase);
1014
1015 rx_enabled(port) = 1;
1016
1017 ret = request_irq(ourport->rx_irq, s3c24xx_serial_rx_chars, 0,
1018 s3c24xx_serial_portname(port), ourport);
1019
1020 if (ret != 0) {
1021 dev_err(port->dev, "cannot get irq %d\n", ourport->rx_irq);
1022 return ret;
1023 }
1024
1025 ourport->rx_claimed = 1;
1026
1027 dbg("requesting tx irq...\n");
1028
1029 tx_enabled(port) = 1;
1030
1031 ret = request_irq(ourport->tx_irq, s3c24xx_serial_tx_chars, 0,
1032 s3c24xx_serial_portname(port), ourport);
1033
1034 if (ret) {
1035 dev_err(port->dev, "cannot get irq %d\n", ourport->tx_irq);
1036 goto err;
1037 }
1038
1039 ourport->tx_claimed = 1;
1040
1041 dbg("s3c24xx_serial_startup ok\n");
1042
1043 /* the port reset code should have done the correct
1044 * register setup for the port controls */
1045
1046 return ret;
1047
1048 err:
1049 s3c24xx_serial_shutdown(port);
1050 return ret;
1051 }
1052
s3c64xx_serial_startup(struct uart_port * port)1053 static int s3c64xx_serial_startup(struct uart_port *port)
1054 {
1055 struct s3c24xx_uart_port *ourport = to_ourport(port);
1056 unsigned long flags;
1057 unsigned int ufcon;
1058 int ret;
1059
1060 dbg("s3c64xx_serial_startup: port=%p (%08llx,%p)\n",
1061 port, (unsigned long long)port->mapbase, port->membase);
1062
1063 wr_regl(port, S3C64XX_UINTM, 0xf);
1064 if (ourport->dma) {
1065 ret = s3c24xx_serial_request_dma(ourport);
1066 if (ret < 0) {
1067 devm_kfree(port->dev, ourport->dma);
1068 ourport->dma = NULL;
1069 }
1070 }
1071
1072 ret = request_irq(port->irq, s3c64xx_serial_handle_irq, IRQF_SHARED,
1073 s3c24xx_serial_portname(port), ourport);
1074 if (ret) {
1075 dev_err(port->dev, "cannot get irq %d\n", port->irq);
1076 return ret;
1077 }
1078
1079 /* For compatibility with s3c24xx Soc's */
1080 rx_enabled(port) = 1;
1081 ourport->rx_claimed = 1;
1082 tx_enabled(port) = 0;
1083 ourport->tx_claimed = 1;
1084
1085 spin_lock_irqsave(&port->lock, flags);
1086
1087 ufcon = rd_regl(port, S3C2410_UFCON);
1088 ufcon |= S3C2410_UFCON_RESETRX | S5PV210_UFCON_RXTRIG8;
1089 if (!uart_console(port))
1090 ufcon |= S3C2410_UFCON_RESETTX;
1091 wr_regl(port, S3C2410_UFCON, ufcon);
1092
1093 enable_rx_pio(ourport);
1094
1095 spin_unlock_irqrestore(&port->lock, flags);
1096
1097 /* Enable Rx Interrupt */
1098 s3c24xx_clear_bit(port, S3C64XX_UINTM_RXD, S3C64XX_UINTM);
1099
1100 dbg("s3c64xx_serial_startup ok\n");
1101 return ret;
1102 }
1103
1104 /* power power management control */
1105
s3c24xx_serial_pm(struct uart_port * port,unsigned int level,unsigned int old)1106 static void s3c24xx_serial_pm(struct uart_port *port, unsigned int level,
1107 unsigned int old)
1108 {
1109 struct s3c24xx_uart_port *ourport = to_ourport(port);
1110 int timeout = 10000;
1111
1112 ourport->pm_level = level;
1113
1114 switch (level) {
1115 case 3:
1116 while (--timeout && !s3c24xx_serial_txempty_nofifo(port))
1117 udelay(100);
1118
1119 if (!IS_ERR(ourport->baudclk))
1120 clk_disable_unprepare(ourport->baudclk);
1121
1122 clk_disable_unprepare(ourport->clk);
1123 break;
1124
1125 case 0:
1126 clk_prepare_enable(ourport->clk);
1127
1128 if (!IS_ERR(ourport->baudclk))
1129 clk_prepare_enable(ourport->baudclk);
1130
1131 break;
1132 default:
1133 dev_err(port->dev, "s3c24xx_serial: unknown pm %d\n", level);
1134 }
1135 }
1136
1137 /* baud rate calculation
1138 *
1139 * The UARTs on the S3C2410/S3C2440 can take their clocks from a number
1140 * of different sources, including the peripheral clock ("pclk") and an
1141 * external clock ("uclk"). The S3C2440 also adds the core clock ("fclk")
1142 * with a programmable extra divisor.
1143 *
1144 * The following code goes through the clock sources, and calculates the
1145 * baud clocks (and the resultant actual baud rates) and then tries to
1146 * pick the closest one and select that.
1147 *
1148 */
1149
1150 #define MAX_CLK_NAME_LENGTH 15
1151
s3c24xx_serial_getsource(struct uart_port * port)1152 static inline int s3c24xx_serial_getsource(struct uart_port *port)
1153 {
1154 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1155 unsigned int ucon;
1156
1157 if (info->num_clks == 1)
1158 return 0;
1159
1160 ucon = rd_regl(port, S3C2410_UCON);
1161 ucon &= info->clksel_mask;
1162 return ucon >> info->clksel_shift;
1163 }
1164
s3c24xx_serial_setsource(struct uart_port * port,unsigned int clk_sel)1165 static void s3c24xx_serial_setsource(struct uart_port *port,
1166 unsigned int clk_sel)
1167 {
1168 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1169 unsigned int ucon;
1170
1171 if (info->num_clks == 1)
1172 return;
1173
1174 ucon = rd_regl(port, S3C2410_UCON);
1175 if ((ucon & info->clksel_mask) >> info->clksel_shift == clk_sel)
1176 return;
1177
1178 ucon &= ~info->clksel_mask;
1179 ucon |= clk_sel << info->clksel_shift;
1180 wr_regl(port, S3C2410_UCON, ucon);
1181 }
1182
s3c24xx_serial_getclk(struct s3c24xx_uart_port * ourport,unsigned int req_baud,struct clk ** best_clk,unsigned int * clk_num)1183 static unsigned int s3c24xx_serial_getclk(struct s3c24xx_uart_port *ourport,
1184 unsigned int req_baud, struct clk **best_clk,
1185 unsigned int *clk_num)
1186 {
1187 struct s3c24xx_uart_info *info = ourport->info;
1188 struct clk *clk;
1189 unsigned long rate;
1190 unsigned int cnt, baud, quot, clk_sel, best_quot = 0;
1191 char clkname[MAX_CLK_NAME_LENGTH];
1192 int calc_deviation, deviation = (1 << 30) - 1;
1193
1194 clk_sel = (ourport->cfg->clk_sel) ? ourport->cfg->clk_sel :
1195 ourport->info->def_clk_sel;
1196 for (cnt = 0; cnt < info->num_clks; cnt++) {
1197 if (!(clk_sel & (1 << cnt)))
1198 continue;
1199
1200 sprintf(clkname, "clk_uart_baud%d", cnt);
1201 clk = clk_get(ourport->port.dev, clkname);
1202 if (IS_ERR(clk))
1203 continue;
1204
1205 rate = clk_get_rate(clk);
1206 if (!rate)
1207 continue;
1208
1209 if (ourport->info->has_divslot) {
1210 unsigned long div = rate / req_baud;
1211
1212 /* The UDIVSLOT register on the newer UARTs allows us to
1213 * get a divisor adjustment of 1/16th on the baud clock.
1214 *
1215 * We don't keep the UDIVSLOT value (the 16ths we
1216 * calculated by not multiplying the baud by 16) as it
1217 * is easy enough to recalculate.
1218 */
1219
1220 quot = div / 16;
1221 baud = rate / div;
1222 } else {
1223 quot = (rate + (8 * req_baud)) / (16 * req_baud);
1224 baud = rate / (quot * 16);
1225 }
1226 quot--;
1227
1228 calc_deviation = req_baud - baud;
1229 if (calc_deviation < 0)
1230 calc_deviation = -calc_deviation;
1231
1232 if (calc_deviation < deviation) {
1233 *best_clk = clk;
1234 best_quot = quot;
1235 *clk_num = cnt;
1236 deviation = calc_deviation;
1237 }
1238 }
1239
1240 return best_quot;
1241 }
1242
1243 /* udivslot_table[]
1244 *
1245 * This table takes the fractional value of the baud divisor and gives
1246 * the recommended setting for the UDIVSLOT register.
1247 */
1248 static u16 udivslot_table[16] = {
1249 [0] = 0x0000,
1250 [1] = 0x0080,
1251 [2] = 0x0808,
1252 [3] = 0x0888,
1253 [4] = 0x2222,
1254 [5] = 0x4924,
1255 [6] = 0x4A52,
1256 [7] = 0x54AA,
1257 [8] = 0x5555,
1258 [9] = 0xD555,
1259 [10] = 0xD5D5,
1260 [11] = 0xDDD5,
1261 [12] = 0xDDDD,
1262 [13] = 0xDFDD,
1263 [14] = 0xDFDF,
1264 [15] = 0xFFDF,
1265 };
1266
s3c24xx_serial_set_termios(struct uart_port * port,struct ktermios * termios,struct ktermios * old)1267 static void s3c24xx_serial_set_termios(struct uart_port *port,
1268 struct ktermios *termios,
1269 struct ktermios *old)
1270 {
1271 struct s3c2410_uartcfg *cfg = s3c24xx_port_to_cfg(port);
1272 struct s3c24xx_uart_port *ourport = to_ourport(port);
1273 struct clk *clk = ERR_PTR(-EINVAL);
1274 unsigned long flags;
1275 unsigned int baud, quot, clk_sel = 0;
1276 unsigned int ulcon;
1277 unsigned int umcon;
1278 unsigned int udivslot = 0;
1279
1280 /*
1281 * We don't support modem control lines.
1282 */
1283 termios->c_cflag &= ~(HUPCL | CMSPAR);
1284 termios->c_cflag |= CLOCAL;
1285
1286 /*
1287 * Ask the core to calculate the divisor for us.
1288 */
1289
1290 baud = uart_get_baud_rate(port, termios, old, 0, 115200*8);
1291 quot = s3c24xx_serial_getclk(ourport, baud, &clk, &clk_sel);
1292 if (baud == 38400 && (port->flags & UPF_SPD_MASK) == UPF_SPD_CUST)
1293 quot = port->custom_divisor;
1294 if (IS_ERR(clk))
1295 return;
1296
1297 /* check to see if we need to change clock source */
1298
1299 if (ourport->baudclk != clk) {
1300 clk_prepare_enable(clk);
1301
1302 s3c24xx_serial_setsource(port, clk_sel);
1303
1304 if (!IS_ERR(ourport->baudclk)) {
1305 clk_disable_unprepare(ourport->baudclk);
1306 ourport->baudclk = ERR_PTR(-EINVAL);
1307 }
1308
1309 ourport->baudclk = clk;
1310 ourport->baudclk_rate = clk ? clk_get_rate(clk) : 0;
1311 }
1312
1313 if (ourport->info->has_divslot) {
1314 unsigned int div = ourport->baudclk_rate / baud;
1315
1316 if (cfg->has_fracval) {
1317 udivslot = (div & 15);
1318 dbg("fracval = %04x\n", udivslot);
1319 } else {
1320 udivslot = udivslot_table[div & 15];
1321 dbg("udivslot = %04x (div %d)\n", udivslot, div & 15);
1322 }
1323 }
1324
1325 switch (termios->c_cflag & CSIZE) {
1326 case CS5:
1327 dbg("config: 5bits/char\n");
1328 ulcon = S3C2410_LCON_CS5;
1329 break;
1330 case CS6:
1331 dbg("config: 6bits/char\n");
1332 ulcon = S3C2410_LCON_CS6;
1333 break;
1334 case CS7:
1335 dbg("config: 7bits/char\n");
1336 ulcon = S3C2410_LCON_CS7;
1337 break;
1338 case CS8:
1339 default:
1340 dbg("config: 8bits/char\n");
1341 ulcon = S3C2410_LCON_CS8;
1342 break;
1343 }
1344
1345 /* preserve original lcon IR settings */
1346 ulcon |= (cfg->ulcon & S3C2410_LCON_IRM);
1347
1348 if (termios->c_cflag & CSTOPB)
1349 ulcon |= S3C2410_LCON_STOPB;
1350
1351 if (termios->c_cflag & PARENB) {
1352 if (termios->c_cflag & PARODD)
1353 ulcon |= S3C2410_LCON_PODD;
1354 else
1355 ulcon |= S3C2410_LCON_PEVEN;
1356 } else {
1357 ulcon |= S3C2410_LCON_PNONE;
1358 }
1359
1360 spin_lock_irqsave(&port->lock, flags);
1361
1362 dbg("setting ulcon to %08x, brddiv to %d, udivslot %08x\n",
1363 ulcon, quot, udivslot);
1364
1365 wr_regl(port, S3C2410_ULCON, ulcon);
1366 wr_regl(port, S3C2410_UBRDIV, quot);
1367
1368 umcon = rd_regl(port, S3C2410_UMCON);
1369 if (termios->c_cflag & CRTSCTS) {
1370 umcon |= S3C2410_UMCOM_AFC;
1371 /* Disable RTS when RX FIFO contains 63 bytes */
1372 umcon &= ~S3C2412_UMCON_AFC_8;
1373 } else {
1374 umcon &= ~S3C2410_UMCOM_AFC;
1375 }
1376 wr_regl(port, S3C2410_UMCON, umcon);
1377
1378 if (ourport->info->has_divslot)
1379 wr_regl(port, S3C2443_DIVSLOT, udivslot);
1380
1381 dbg("uart: ulcon = 0x%08x, ucon = 0x%08x, ufcon = 0x%08x\n",
1382 rd_regl(port, S3C2410_ULCON),
1383 rd_regl(port, S3C2410_UCON),
1384 rd_regl(port, S3C2410_UFCON));
1385
1386 /*
1387 * Update the per-port timeout.
1388 */
1389 uart_update_timeout(port, termios->c_cflag, baud);
1390
1391 /*
1392 * Which character status flags are we interested in?
1393 */
1394 port->read_status_mask = S3C2410_UERSTAT_OVERRUN;
1395 if (termios->c_iflag & INPCK)
1396 port->read_status_mask |= S3C2410_UERSTAT_FRAME |
1397 S3C2410_UERSTAT_PARITY;
1398 /*
1399 * Which character status flags should we ignore?
1400 */
1401 port->ignore_status_mask = 0;
1402 if (termios->c_iflag & IGNPAR)
1403 port->ignore_status_mask |= S3C2410_UERSTAT_OVERRUN;
1404 if (termios->c_iflag & IGNBRK && termios->c_iflag & IGNPAR)
1405 port->ignore_status_mask |= S3C2410_UERSTAT_FRAME;
1406
1407 /*
1408 * Ignore all characters if CREAD is not set.
1409 */
1410 if ((termios->c_cflag & CREAD) == 0)
1411 port->ignore_status_mask |= RXSTAT_DUMMY_READ;
1412
1413 spin_unlock_irqrestore(&port->lock, flags);
1414 }
1415
s3c24xx_serial_type(struct uart_port * port)1416 static const char *s3c24xx_serial_type(struct uart_port *port)
1417 {
1418 switch (port->type) {
1419 case PORT_S3C2410:
1420 return "S3C2410";
1421 case PORT_S3C2440:
1422 return "S3C2440";
1423 case PORT_S3C2412:
1424 return "S3C2412";
1425 case PORT_S3C6400:
1426 return "S3C6400/10";
1427 default:
1428 return NULL;
1429 }
1430 }
1431
1432 #define MAP_SIZE (0x100)
1433
s3c24xx_serial_release_port(struct uart_port * port)1434 static void s3c24xx_serial_release_port(struct uart_port *port)
1435 {
1436 release_mem_region(port->mapbase, MAP_SIZE);
1437 }
1438
s3c24xx_serial_request_port(struct uart_port * port)1439 static int s3c24xx_serial_request_port(struct uart_port *port)
1440 {
1441 const char *name = s3c24xx_serial_portname(port);
1442 return request_mem_region(port->mapbase, MAP_SIZE, name) ? 0 : -EBUSY;
1443 }
1444
s3c24xx_serial_config_port(struct uart_port * port,int flags)1445 static void s3c24xx_serial_config_port(struct uart_port *port, int flags)
1446 {
1447 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1448
1449 if (flags & UART_CONFIG_TYPE &&
1450 s3c24xx_serial_request_port(port) == 0)
1451 port->type = info->type;
1452 }
1453
1454 /*
1455 * verify the new serial_struct (for TIOCSSERIAL).
1456 */
1457 static int
s3c24xx_serial_verify_port(struct uart_port * port,struct serial_struct * ser)1458 s3c24xx_serial_verify_port(struct uart_port *port, struct serial_struct *ser)
1459 {
1460 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1461
1462 if (ser->type != PORT_UNKNOWN && ser->type != info->type)
1463 return -EINVAL;
1464
1465 return 0;
1466 }
1467
1468
1469 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
1470
1471 static struct console s3c24xx_serial_console;
1472
s3c24xx_serial_console_init(void)1473 static int __init s3c24xx_serial_console_init(void)
1474 {
1475 register_console(&s3c24xx_serial_console);
1476 return 0;
1477 }
1478 console_initcall(s3c24xx_serial_console_init);
1479
1480 #define S3C24XX_SERIAL_CONSOLE &s3c24xx_serial_console
1481 #else
1482 #define S3C24XX_SERIAL_CONSOLE NULL
1483 #endif
1484
1485 #if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
1486 static int s3c24xx_serial_get_poll_char(struct uart_port *port);
1487 static void s3c24xx_serial_put_poll_char(struct uart_port *port,
1488 unsigned char c);
1489 #endif
1490
1491 static struct uart_ops s3c24xx_serial_ops = {
1492 .pm = s3c24xx_serial_pm,
1493 .tx_empty = s3c24xx_serial_tx_empty,
1494 .get_mctrl = s3c24xx_serial_get_mctrl,
1495 .set_mctrl = s3c24xx_serial_set_mctrl,
1496 .stop_tx = s3c24xx_serial_stop_tx,
1497 .start_tx = s3c24xx_serial_start_tx,
1498 .stop_rx = s3c24xx_serial_stop_rx,
1499 .break_ctl = s3c24xx_serial_break_ctl,
1500 .startup = s3c24xx_serial_startup,
1501 .shutdown = s3c24xx_serial_shutdown,
1502 .set_termios = s3c24xx_serial_set_termios,
1503 .type = s3c24xx_serial_type,
1504 .release_port = s3c24xx_serial_release_port,
1505 .request_port = s3c24xx_serial_request_port,
1506 .config_port = s3c24xx_serial_config_port,
1507 .verify_port = s3c24xx_serial_verify_port,
1508 #if defined(CONFIG_SERIAL_SAMSUNG_CONSOLE) && defined(CONFIG_CONSOLE_POLL)
1509 .poll_get_char = s3c24xx_serial_get_poll_char,
1510 .poll_put_char = s3c24xx_serial_put_poll_char,
1511 #endif
1512 };
1513
1514 static struct uart_driver s3c24xx_uart_drv = {
1515 .owner = THIS_MODULE,
1516 .driver_name = "s3c2410_serial",
1517 .nr = CONFIG_SERIAL_SAMSUNG_UARTS,
1518 .cons = S3C24XX_SERIAL_CONSOLE,
1519 .dev_name = S3C24XX_SERIAL_NAME,
1520 .major = S3C24XX_SERIAL_MAJOR,
1521 .minor = S3C24XX_SERIAL_MINOR,
1522 };
1523
1524 #define __PORT_LOCK_UNLOCKED(i) \
1525 __SPIN_LOCK_UNLOCKED(s3c24xx_serial_ports[i].port.lock)
1526 static struct s3c24xx_uart_port
1527 s3c24xx_serial_ports[CONFIG_SERIAL_SAMSUNG_UARTS] = {
1528 [0] = {
1529 .port = {
1530 .lock = __PORT_LOCK_UNLOCKED(0),
1531 .iotype = UPIO_MEM,
1532 .uartclk = 0,
1533 .fifosize = 16,
1534 .ops = &s3c24xx_serial_ops,
1535 .flags = UPF_BOOT_AUTOCONF,
1536 .line = 0,
1537 }
1538 },
1539 [1] = {
1540 .port = {
1541 .lock = __PORT_LOCK_UNLOCKED(1),
1542 .iotype = UPIO_MEM,
1543 .uartclk = 0,
1544 .fifosize = 16,
1545 .ops = &s3c24xx_serial_ops,
1546 .flags = UPF_BOOT_AUTOCONF,
1547 .line = 1,
1548 }
1549 },
1550 #if CONFIG_SERIAL_SAMSUNG_UARTS > 2
1551
1552 [2] = {
1553 .port = {
1554 .lock = __PORT_LOCK_UNLOCKED(2),
1555 .iotype = UPIO_MEM,
1556 .uartclk = 0,
1557 .fifosize = 16,
1558 .ops = &s3c24xx_serial_ops,
1559 .flags = UPF_BOOT_AUTOCONF,
1560 .line = 2,
1561 }
1562 },
1563 #endif
1564 #if CONFIG_SERIAL_SAMSUNG_UARTS > 3
1565 [3] = {
1566 .port = {
1567 .lock = __PORT_LOCK_UNLOCKED(3),
1568 .iotype = UPIO_MEM,
1569 .uartclk = 0,
1570 .fifosize = 16,
1571 .ops = &s3c24xx_serial_ops,
1572 .flags = UPF_BOOT_AUTOCONF,
1573 .line = 3,
1574 }
1575 }
1576 #endif
1577 };
1578 #undef __PORT_LOCK_UNLOCKED
1579
1580 /* s3c24xx_serial_resetport
1581 *
1582 * reset the fifos and other the settings.
1583 */
1584
s3c24xx_serial_resetport(struct uart_port * port,struct s3c2410_uartcfg * cfg)1585 static void s3c24xx_serial_resetport(struct uart_port *port,
1586 struct s3c2410_uartcfg *cfg)
1587 {
1588 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1589 unsigned long ucon = rd_regl(port, S3C2410_UCON);
1590 unsigned int ucon_mask;
1591
1592 ucon_mask = info->clksel_mask;
1593 if (info->type == PORT_S3C2440)
1594 ucon_mask |= S3C2440_UCON0_DIVMASK;
1595
1596 ucon &= ucon_mask;
1597 wr_regl(port, S3C2410_UCON, ucon | cfg->ucon);
1598
1599 /* reset both fifos */
1600 wr_regl(port, S3C2410_UFCON, cfg->ufcon | S3C2410_UFCON_RESETBOTH);
1601 wr_regl(port, S3C2410_UFCON, cfg->ufcon);
1602
1603 /* some delay is required after fifo reset */
1604 udelay(1);
1605 }
1606
1607
1608 #ifdef CONFIG_ARM_S3C24XX_CPUFREQ
1609
s3c24xx_serial_cpufreq_transition(struct notifier_block * nb,unsigned long val,void * data)1610 static int s3c24xx_serial_cpufreq_transition(struct notifier_block *nb,
1611 unsigned long val, void *data)
1612 {
1613 struct s3c24xx_uart_port *port;
1614 struct uart_port *uport;
1615
1616 port = container_of(nb, struct s3c24xx_uart_port, freq_transition);
1617 uport = &port->port;
1618
1619 /* check to see if port is enabled */
1620
1621 if (port->pm_level != 0)
1622 return 0;
1623
1624 /* try and work out if the baudrate is changing, we can detect
1625 * a change in rate, but we do not have support for detecting
1626 * a disturbance in the clock-rate over the change.
1627 */
1628
1629 if (IS_ERR(port->baudclk))
1630 goto exit;
1631
1632 if (port->baudclk_rate == clk_get_rate(port->baudclk))
1633 goto exit;
1634
1635 if (val == CPUFREQ_PRECHANGE) {
1636 /* we should really shut the port down whilst the
1637 * frequency change is in progress. */
1638
1639 } else if (val == CPUFREQ_POSTCHANGE) {
1640 struct ktermios *termios;
1641 struct tty_struct *tty;
1642
1643 if (uport->state == NULL)
1644 goto exit;
1645
1646 tty = uport->state->port.tty;
1647
1648 if (tty == NULL)
1649 goto exit;
1650
1651 termios = &tty->termios;
1652
1653 if (termios == NULL) {
1654 dev_warn(uport->dev, "%s: no termios?\n", __func__);
1655 goto exit;
1656 }
1657
1658 s3c24xx_serial_set_termios(uport, termios, NULL);
1659 }
1660
1661 exit:
1662 return 0;
1663 }
1664
1665 static inline int
s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port * port)1666 s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port *port)
1667 {
1668 port->freq_transition.notifier_call = s3c24xx_serial_cpufreq_transition;
1669
1670 return cpufreq_register_notifier(&port->freq_transition,
1671 CPUFREQ_TRANSITION_NOTIFIER);
1672 }
1673
1674 static inline void
s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port * port)1675 s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port *port)
1676 {
1677 cpufreq_unregister_notifier(&port->freq_transition,
1678 CPUFREQ_TRANSITION_NOTIFIER);
1679 }
1680
1681 #else
1682 static inline int
s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port * port)1683 s3c24xx_serial_cpufreq_register(struct s3c24xx_uart_port *port)
1684 {
1685 return 0;
1686 }
1687
1688 static inline void
s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port * port)1689 s3c24xx_serial_cpufreq_deregister(struct s3c24xx_uart_port *port)
1690 {
1691 }
1692 #endif
1693
1694 /* s3c24xx_serial_init_port
1695 *
1696 * initialise a single serial port from the platform device given
1697 */
1698
s3c24xx_serial_init_port(struct s3c24xx_uart_port * ourport,struct platform_device * platdev)1699 static int s3c24xx_serial_init_port(struct s3c24xx_uart_port *ourport,
1700 struct platform_device *platdev)
1701 {
1702 struct uart_port *port = &ourport->port;
1703 struct s3c2410_uartcfg *cfg = ourport->cfg;
1704 struct resource *res;
1705 int ret;
1706
1707 dbg("s3c24xx_serial_init_port: port=%p, platdev=%p\n", port, platdev);
1708
1709 if (platdev == NULL)
1710 return -ENODEV;
1711
1712 if (port->mapbase != 0)
1713 return -EINVAL;
1714
1715 /* setup info for port */
1716 port->dev = &platdev->dev;
1717
1718 /* Startup sequence is different for s3c64xx and higher SoC's */
1719 if (s3c24xx_serial_has_interrupt_mask(port))
1720 s3c24xx_serial_ops.startup = s3c64xx_serial_startup;
1721
1722 port->uartclk = 1;
1723
1724 if (cfg->uart_flags & UPF_CONS_FLOW) {
1725 dbg("s3c24xx_serial_init_port: enabling flow control\n");
1726 port->flags |= UPF_CONS_FLOW;
1727 }
1728
1729 /* sort our the physical and virtual addresses for each UART */
1730
1731 res = platform_get_resource(platdev, IORESOURCE_MEM, 0);
1732 if (res == NULL) {
1733 dev_err(port->dev, "failed to find memory resource for uart\n");
1734 return -EINVAL;
1735 }
1736
1737 dbg("resource %pR)\n", res);
1738
1739 port->membase = devm_ioremap(port->dev, res->start, resource_size(res));
1740 if (!port->membase) {
1741 dev_err(port->dev, "failed to remap controller address\n");
1742 return -EBUSY;
1743 }
1744
1745 port->mapbase = res->start;
1746 ret = platform_get_irq(platdev, 0);
1747 if (ret < 0)
1748 port->irq = 0;
1749 else {
1750 port->irq = ret;
1751 ourport->rx_irq = ret;
1752 ourport->tx_irq = ret + 1;
1753 }
1754
1755 ret = platform_get_irq(platdev, 1);
1756 if (ret > 0)
1757 ourport->tx_irq = ret;
1758 /*
1759 * DMA is currently supported only on DT platforms, if DMA properties
1760 * are specified.
1761 */
1762 if (platdev->dev.of_node && of_find_property(platdev->dev.of_node,
1763 "dmas", NULL)) {
1764 ourport->dma = devm_kzalloc(port->dev,
1765 sizeof(*ourport->dma),
1766 GFP_KERNEL);
1767 if (!ourport->dma) {
1768 ret = -ENOMEM;
1769 goto err;
1770 }
1771 }
1772
1773 ourport->clk = clk_get(&platdev->dev, "uart");
1774 if (IS_ERR(ourport->clk)) {
1775 pr_err("%s: Controller clock not found\n",
1776 dev_name(&platdev->dev));
1777 ret = PTR_ERR(ourport->clk);
1778 goto err;
1779 }
1780
1781 ret = clk_prepare_enable(ourport->clk);
1782 if (ret) {
1783 pr_err("uart: clock failed to prepare+enable: %d\n", ret);
1784 clk_put(ourport->clk);
1785 goto err;
1786 }
1787
1788 /* Keep all interrupts masked and cleared */
1789 if (s3c24xx_serial_has_interrupt_mask(port)) {
1790 wr_regl(port, S3C64XX_UINTM, 0xf);
1791 wr_regl(port, S3C64XX_UINTP, 0xf);
1792 wr_regl(port, S3C64XX_UINTSP, 0xf);
1793 }
1794
1795 dbg("port: map=%pa, mem=%p, irq=%d (%d,%d), clock=%u\n",
1796 &port->mapbase, port->membase, port->irq,
1797 ourport->rx_irq, ourport->tx_irq, port->uartclk);
1798
1799 /* reset the fifos (and setup the uart) */
1800 s3c24xx_serial_resetport(port, cfg);
1801
1802 return 0;
1803
1804 err:
1805 port->mapbase = 0;
1806 return ret;
1807 }
1808
1809 /* Device driver serial port probe */
1810
1811 static const struct of_device_id s3c24xx_uart_dt_match[];
1812 static int probe_index;
1813
s3c24xx_get_driver_data(struct platform_device * pdev)1814 static inline struct s3c24xx_serial_drv_data *s3c24xx_get_driver_data(
1815 struct platform_device *pdev)
1816 {
1817 #ifdef CONFIG_OF
1818 if (pdev->dev.of_node) {
1819 const struct of_device_id *match;
1820 match = of_match_node(s3c24xx_uart_dt_match, pdev->dev.of_node);
1821 return (struct s3c24xx_serial_drv_data *)match->data;
1822 }
1823 #endif
1824 return (struct s3c24xx_serial_drv_data *)
1825 platform_get_device_id(pdev)->driver_data;
1826 }
1827
s3c24xx_serial_probe(struct platform_device * pdev)1828 static int s3c24xx_serial_probe(struct platform_device *pdev)
1829 {
1830 struct device_node *np = pdev->dev.of_node;
1831 struct s3c24xx_uart_port *ourport;
1832 int index = probe_index;
1833 int ret;
1834
1835 if (np) {
1836 ret = of_alias_get_id(np, "serial");
1837 if (ret >= 0)
1838 index = ret;
1839 }
1840
1841 dbg("s3c24xx_serial_probe(%p) %d\n", pdev, index);
1842
1843 if (index >= ARRAY_SIZE(s3c24xx_serial_ports)) {
1844 dev_err(&pdev->dev, "serial%d out of range\n", index);
1845 return -EINVAL;
1846 }
1847 ourport = &s3c24xx_serial_ports[index];
1848
1849 ourport->drv_data = s3c24xx_get_driver_data(pdev);
1850 if (!ourport->drv_data) {
1851 dev_err(&pdev->dev, "could not find driver data\n");
1852 return -ENODEV;
1853 }
1854
1855 ourport->baudclk = ERR_PTR(-EINVAL);
1856 ourport->info = ourport->drv_data->info;
1857 ourport->cfg = (dev_get_platdata(&pdev->dev)) ?
1858 dev_get_platdata(&pdev->dev) :
1859 ourport->drv_data->def_cfg;
1860
1861 if (np)
1862 of_property_read_u32(np,
1863 "samsung,uart-fifosize", &ourport->port.fifosize);
1864
1865 if (ourport->drv_data->fifosize[index])
1866 ourport->port.fifosize = ourport->drv_data->fifosize[index];
1867 else if (ourport->info->fifosize)
1868 ourport->port.fifosize = ourport->info->fifosize;
1869
1870 /*
1871 * DMA transfers must be aligned at least to cache line size,
1872 * so find minimal transfer size suitable for DMA mode
1873 */
1874 ourport->min_dma_size = max_t(int, ourport->port.fifosize,
1875 dma_get_cache_alignment());
1876
1877 dbg("%s: initialising port %p...\n", __func__, ourport);
1878
1879 ret = s3c24xx_serial_init_port(ourport, pdev);
1880 if (ret < 0)
1881 return ret;
1882
1883 if (!s3c24xx_uart_drv.state) {
1884 ret = uart_register_driver(&s3c24xx_uart_drv);
1885 if (ret < 0) {
1886 pr_err("Failed to register Samsung UART driver\n");
1887 return ret;
1888 }
1889 }
1890
1891 dbg("%s: adding port\n", __func__);
1892 uart_add_one_port(&s3c24xx_uart_drv, &ourport->port);
1893 platform_set_drvdata(pdev, &ourport->port);
1894
1895 /*
1896 * Deactivate the clock enabled in s3c24xx_serial_init_port here,
1897 * so that a potential re-enablement through the pm-callback overlaps
1898 * and keeps the clock enabled in this case.
1899 */
1900 clk_disable_unprepare(ourport->clk);
1901
1902 ret = s3c24xx_serial_cpufreq_register(ourport);
1903 if (ret < 0)
1904 dev_err(&pdev->dev, "failed to add cpufreq notifier\n");
1905
1906 probe_index++;
1907
1908 return 0;
1909 }
1910
s3c24xx_serial_remove(struct platform_device * dev)1911 static int s3c24xx_serial_remove(struct platform_device *dev)
1912 {
1913 struct uart_port *port = s3c24xx_dev_to_port(&dev->dev);
1914
1915 if (port) {
1916 s3c24xx_serial_cpufreq_deregister(to_ourport(port));
1917 uart_remove_one_port(&s3c24xx_uart_drv, port);
1918 }
1919
1920 uart_unregister_driver(&s3c24xx_uart_drv);
1921
1922 return 0;
1923 }
1924
1925 /* UART power management code */
1926 #ifdef CONFIG_PM_SLEEP
s3c24xx_serial_suspend(struct device * dev)1927 static int s3c24xx_serial_suspend(struct device *dev)
1928 {
1929 struct uart_port *port = s3c24xx_dev_to_port(dev);
1930
1931 if (port)
1932 uart_suspend_port(&s3c24xx_uart_drv, port);
1933
1934 return 0;
1935 }
1936
s3c24xx_serial_resume(struct device * dev)1937 static int s3c24xx_serial_resume(struct device *dev)
1938 {
1939 struct uart_port *port = s3c24xx_dev_to_port(dev);
1940 struct s3c24xx_uart_port *ourport = to_ourport(port);
1941
1942 if (port) {
1943 clk_prepare_enable(ourport->clk);
1944 s3c24xx_serial_resetport(port, s3c24xx_port_to_cfg(port));
1945 clk_disable_unprepare(ourport->clk);
1946
1947 uart_resume_port(&s3c24xx_uart_drv, port);
1948 }
1949
1950 return 0;
1951 }
1952
s3c24xx_serial_resume_noirq(struct device * dev)1953 static int s3c24xx_serial_resume_noirq(struct device *dev)
1954 {
1955 struct uart_port *port = s3c24xx_dev_to_port(dev);
1956 struct s3c24xx_uart_port *ourport = to_ourport(port);
1957
1958 if (port) {
1959 /* restore IRQ mask */
1960 if (s3c24xx_serial_has_interrupt_mask(port)) {
1961 unsigned int uintm = 0xf;
1962 if (tx_enabled(port))
1963 uintm &= ~S3C64XX_UINTM_TXD_MSK;
1964 if (rx_enabled(port))
1965 uintm &= ~S3C64XX_UINTM_RXD_MSK;
1966 clk_prepare_enable(ourport->clk);
1967 wr_regl(port, S3C64XX_UINTM, uintm);
1968 clk_disable_unprepare(ourport->clk);
1969 }
1970 }
1971
1972 return 0;
1973 }
1974
1975 static const struct dev_pm_ops s3c24xx_serial_pm_ops = {
1976 .suspend = s3c24xx_serial_suspend,
1977 .resume = s3c24xx_serial_resume,
1978 .resume_noirq = s3c24xx_serial_resume_noirq,
1979 };
1980 #define SERIAL_SAMSUNG_PM_OPS (&s3c24xx_serial_pm_ops)
1981
1982 #else /* !CONFIG_PM_SLEEP */
1983
1984 #define SERIAL_SAMSUNG_PM_OPS NULL
1985 #endif /* CONFIG_PM_SLEEP */
1986
1987 /* Console code */
1988
1989 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
1990
1991 static struct uart_port *cons_uart;
1992
1993 static int
s3c24xx_serial_console_txrdy(struct uart_port * port,unsigned int ufcon)1994 s3c24xx_serial_console_txrdy(struct uart_port *port, unsigned int ufcon)
1995 {
1996 struct s3c24xx_uart_info *info = s3c24xx_port_to_info(port);
1997 unsigned long ufstat, utrstat;
1998
1999 if (ufcon & S3C2410_UFCON_FIFOMODE) {
2000 /* fifo mode - check amount of data in fifo registers... */
2001
2002 ufstat = rd_regl(port, S3C2410_UFSTAT);
2003 return (ufstat & info->tx_fifofull) ? 0 : 1;
2004 }
2005
2006 /* in non-fifo mode, we go and use the tx buffer empty */
2007
2008 utrstat = rd_regl(port, S3C2410_UTRSTAT);
2009 return (utrstat & S3C2410_UTRSTAT_TXE) ? 1 : 0;
2010 }
2011
2012 static bool
s3c24xx_port_configured(unsigned int ucon)2013 s3c24xx_port_configured(unsigned int ucon)
2014 {
2015 /* consider the serial port configured if the tx/rx mode set */
2016 return (ucon & 0xf) != 0;
2017 }
2018
2019 #ifdef CONFIG_CONSOLE_POLL
2020 /*
2021 * Console polling routines for writing and reading from the uart while
2022 * in an interrupt or debug context.
2023 */
2024
s3c24xx_serial_get_poll_char(struct uart_port * port)2025 static int s3c24xx_serial_get_poll_char(struct uart_port *port)
2026 {
2027 struct s3c24xx_uart_port *ourport = to_ourport(port);
2028 unsigned int ufstat;
2029
2030 ufstat = rd_regl(port, S3C2410_UFSTAT);
2031 if (s3c24xx_serial_rx_fifocnt(ourport, ufstat) == 0)
2032 return NO_POLL_CHAR;
2033
2034 return rd_regb(port, S3C2410_URXH);
2035 }
2036
s3c24xx_serial_put_poll_char(struct uart_port * port,unsigned char c)2037 static void s3c24xx_serial_put_poll_char(struct uart_port *port,
2038 unsigned char c)
2039 {
2040 unsigned int ufcon = rd_regl(port, S3C2410_UFCON);
2041 unsigned int ucon = rd_regl(port, S3C2410_UCON);
2042
2043 /* not possible to xmit on unconfigured port */
2044 if (!s3c24xx_port_configured(ucon))
2045 return;
2046
2047 while (!s3c24xx_serial_console_txrdy(port, ufcon))
2048 cpu_relax();
2049 wr_regb(port, S3C2410_UTXH, c);
2050 }
2051
2052 #endif /* CONFIG_CONSOLE_POLL */
2053
2054 static void
s3c24xx_serial_console_putchar(struct uart_port * port,int ch)2055 s3c24xx_serial_console_putchar(struct uart_port *port, int ch)
2056 {
2057 unsigned int ufcon = rd_regl(port, S3C2410_UFCON);
2058
2059 while (!s3c24xx_serial_console_txrdy(port, ufcon))
2060 cpu_relax();
2061 wr_regb(port, S3C2410_UTXH, ch);
2062 }
2063
2064 static void
s3c24xx_serial_console_write(struct console * co,const char * s,unsigned int count)2065 s3c24xx_serial_console_write(struct console *co, const char *s,
2066 unsigned int count)
2067 {
2068 unsigned int ucon = rd_regl(cons_uart, S3C2410_UCON);
2069
2070 /* not possible to xmit on unconfigured port */
2071 if (!s3c24xx_port_configured(ucon))
2072 return;
2073
2074 uart_console_write(cons_uart, s, count, s3c24xx_serial_console_putchar);
2075 }
2076
2077 static void __init
s3c24xx_serial_get_options(struct uart_port * port,int * baud,int * parity,int * bits)2078 s3c24xx_serial_get_options(struct uart_port *port, int *baud,
2079 int *parity, int *bits)
2080 {
2081 struct clk *clk;
2082 unsigned int ulcon;
2083 unsigned int ucon;
2084 unsigned int ubrdiv;
2085 unsigned long rate;
2086 unsigned int clk_sel;
2087 char clk_name[MAX_CLK_NAME_LENGTH];
2088
2089 ulcon = rd_regl(port, S3C2410_ULCON);
2090 ucon = rd_regl(port, S3C2410_UCON);
2091 ubrdiv = rd_regl(port, S3C2410_UBRDIV);
2092
2093 dbg("s3c24xx_serial_get_options: port=%p\n"
2094 "registers: ulcon=%08x, ucon=%08x, ubdriv=%08x\n",
2095 port, ulcon, ucon, ubrdiv);
2096
2097 if (s3c24xx_port_configured(ucon)) {
2098 switch (ulcon & S3C2410_LCON_CSMASK) {
2099 case S3C2410_LCON_CS5:
2100 *bits = 5;
2101 break;
2102 case S3C2410_LCON_CS6:
2103 *bits = 6;
2104 break;
2105 case S3C2410_LCON_CS7:
2106 *bits = 7;
2107 break;
2108 case S3C2410_LCON_CS8:
2109 default:
2110 *bits = 8;
2111 break;
2112 }
2113
2114 switch (ulcon & S3C2410_LCON_PMASK) {
2115 case S3C2410_LCON_PEVEN:
2116 *parity = 'e';
2117 break;
2118
2119 case S3C2410_LCON_PODD:
2120 *parity = 'o';
2121 break;
2122
2123 case S3C2410_LCON_PNONE:
2124 default:
2125 *parity = 'n';
2126 }
2127
2128 /* now calculate the baud rate */
2129
2130 clk_sel = s3c24xx_serial_getsource(port);
2131 sprintf(clk_name, "clk_uart_baud%d", clk_sel);
2132
2133 clk = clk_get(port->dev, clk_name);
2134 if (!IS_ERR(clk))
2135 rate = clk_get_rate(clk);
2136 else
2137 rate = 1;
2138
2139 *baud = rate / (16 * (ubrdiv + 1));
2140 dbg("calculated baud %d\n", *baud);
2141 }
2142
2143 }
2144
2145 static int __init
s3c24xx_serial_console_setup(struct console * co,char * options)2146 s3c24xx_serial_console_setup(struct console *co, char *options)
2147 {
2148 struct uart_port *port;
2149 int baud = 9600;
2150 int bits = 8;
2151 int parity = 'n';
2152 int flow = 'n';
2153
2154 dbg("s3c24xx_serial_console_setup: co=%p (%d), %s\n",
2155 co, co->index, options);
2156
2157 /* is this a valid port */
2158
2159 if (co->index == -1 || co->index >= CONFIG_SERIAL_SAMSUNG_UARTS)
2160 co->index = 0;
2161
2162 port = &s3c24xx_serial_ports[co->index].port;
2163
2164 /* is the port configured? */
2165
2166 if (port->mapbase == 0x0)
2167 return -ENODEV;
2168
2169 cons_uart = port;
2170
2171 dbg("s3c24xx_serial_console_setup: port=%p (%d)\n", port, co->index);
2172
2173 /*
2174 * Check whether an invalid uart number has been specified, and
2175 * if so, search for the first available port that does have
2176 * console support.
2177 */
2178 if (options)
2179 uart_parse_options(options, &baud, &parity, &bits, &flow);
2180 else
2181 s3c24xx_serial_get_options(port, &baud, &parity, &bits);
2182
2183 dbg("s3c24xx_serial_console_setup: baud %d\n", baud);
2184
2185 return uart_set_options(port, co, baud, parity, bits, flow);
2186 }
2187
2188 static struct console s3c24xx_serial_console = {
2189 .name = S3C24XX_SERIAL_NAME,
2190 .device = uart_console_device,
2191 .flags = CON_PRINTBUFFER,
2192 .index = -1,
2193 .write = s3c24xx_serial_console_write,
2194 .setup = s3c24xx_serial_console_setup,
2195 .data = &s3c24xx_uart_drv,
2196 };
2197 #endif /* CONFIG_SERIAL_SAMSUNG_CONSOLE */
2198
2199 #ifdef CONFIG_CPU_S3C2410
2200 static struct s3c24xx_serial_drv_data s3c2410_serial_drv_data = {
2201 .info = &(struct s3c24xx_uart_info) {
2202 .name = "Samsung S3C2410 UART",
2203 .type = PORT_S3C2410,
2204 .fifosize = 16,
2205 .rx_fifomask = S3C2410_UFSTAT_RXMASK,
2206 .rx_fifoshift = S3C2410_UFSTAT_RXSHIFT,
2207 .rx_fifofull = S3C2410_UFSTAT_RXFULL,
2208 .tx_fifofull = S3C2410_UFSTAT_TXFULL,
2209 .tx_fifomask = S3C2410_UFSTAT_TXMASK,
2210 .tx_fifoshift = S3C2410_UFSTAT_TXSHIFT,
2211 .def_clk_sel = S3C2410_UCON_CLKSEL0,
2212 .num_clks = 2,
2213 .clksel_mask = S3C2410_UCON_CLKMASK,
2214 .clksel_shift = S3C2410_UCON_CLKSHIFT,
2215 },
2216 .def_cfg = &(struct s3c2410_uartcfg) {
2217 .ucon = S3C2410_UCON_DEFAULT,
2218 .ufcon = S3C2410_UFCON_DEFAULT,
2219 },
2220 };
2221 #define S3C2410_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c2410_serial_drv_data)
2222 #else
2223 #define S3C2410_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2224 #endif
2225
2226 #ifdef CONFIG_CPU_S3C2412
2227 static struct s3c24xx_serial_drv_data s3c2412_serial_drv_data = {
2228 .info = &(struct s3c24xx_uart_info) {
2229 .name = "Samsung S3C2412 UART",
2230 .type = PORT_S3C2412,
2231 .fifosize = 64,
2232 .has_divslot = 1,
2233 .rx_fifomask = S3C2440_UFSTAT_RXMASK,
2234 .rx_fifoshift = S3C2440_UFSTAT_RXSHIFT,
2235 .rx_fifofull = S3C2440_UFSTAT_RXFULL,
2236 .tx_fifofull = S3C2440_UFSTAT_TXFULL,
2237 .tx_fifomask = S3C2440_UFSTAT_TXMASK,
2238 .tx_fifoshift = S3C2440_UFSTAT_TXSHIFT,
2239 .def_clk_sel = S3C2410_UCON_CLKSEL2,
2240 .num_clks = 4,
2241 .clksel_mask = S3C2412_UCON_CLKMASK,
2242 .clksel_shift = S3C2412_UCON_CLKSHIFT,
2243 },
2244 .def_cfg = &(struct s3c2410_uartcfg) {
2245 .ucon = S3C2410_UCON_DEFAULT,
2246 .ufcon = S3C2410_UFCON_DEFAULT,
2247 },
2248 };
2249 #define S3C2412_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c2412_serial_drv_data)
2250 #else
2251 #define S3C2412_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2252 #endif
2253
2254 #if defined(CONFIG_CPU_S3C2440) || defined(CONFIG_CPU_S3C2416) || \
2255 defined(CONFIG_CPU_S3C2443) || defined(CONFIG_CPU_S3C2442)
2256 static struct s3c24xx_serial_drv_data s3c2440_serial_drv_data = {
2257 .info = &(struct s3c24xx_uart_info) {
2258 .name = "Samsung S3C2440 UART",
2259 .type = PORT_S3C2440,
2260 .fifosize = 64,
2261 .has_divslot = 1,
2262 .rx_fifomask = S3C2440_UFSTAT_RXMASK,
2263 .rx_fifoshift = S3C2440_UFSTAT_RXSHIFT,
2264 .rx_fifofull = S3C2440_UFSTAT_RXFULL,
2265 .tx_fifofull = S3C2440_UFSTAT_TXFULL,
2266 .tx_fifomask = S3C2440_UFSTAT_TXMASK,
2267 .tx_fifoshift = S3C2440_UFSTAT_TXSHIFT,
2268 .def_clk_sel = S3C2410_UCON_CLKSEL2,
2269 .num_clks = 4,
2270 .clksel_mask = S3C2412_UCON_CLKMASK,
2271 .clksel_shift = S3C2412_UCON_CLKSHIFT,
2272 },
2273 .def_cfg = &(struct s3c2410_uartcfg) {
2274 .ucon = S3C2410_UCON_DEFAULT,
2275 .ufcon = S3C2410_UFCON_DEFAULT,
2276 },
2277 };
2278 #define S3C2440_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c2440_serial_drv_data)
2279 #else
2280 #define S3C2440_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2281 #endif
2282
2283 #if defined(CONFIG_CPU_S3C6400) || defined(CONFIG_CPU_S3C6410)
2284 static struct s3c24xx_serial_drv_data s3c6400_serial_drv_data = {
2285 .info = &(struct s3c24xx_uart_info) {
2286 .name = "Samsung S3C6400 UART",
2287 .type = PORT_S3C6400,
2288 .fifosize = 64,
2289 .has_divslot = 1,
2290 .rx_fifomask = S3C2440_UFSTAT_RXMASK,
2291 .rx_fifoshift = S3C2440_UFSTAT_RXSHIFT,
2292 .rx_fifofull = S3C2440_UFSTAT_RXFULL,
2293 .tx_fifofull = S3C2440_UFSTAT_TXFULL,
2294 .tx_fifomask = S3C2440_UFSTAT_TXMASK,
2295 .tx_fifoshift = S3C2440_UFSTAT_TXSHIFT,
2296 .def_clk_sel = S3C2410_UCON_CLKSEL2,
2297 .num_clks = 4,
2298 .clksel_mask = S3C6400_UCON_CLKMASK,
2299 .clksel_shift = S3C6400_UCON_CLKSHIFT,
2300 },
2301 .def_cfg = &(struct s3c2410_uartcfg) {
2302 .ucon = S3C2410_UCON_DEFAULT,
2303 .ufcon = S3C2410_UFCON_DEFAULT,
2304 },
2305 };
2306 #define S3C6400_SERIAL_DRV_DATA ((kernel_ulong_t)&s3c6400_serial_drv_data)
2307 #else
2308 #define S3C6400_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2309 #endif
2310
2311 #ifdef CONFIG_CPU_S5PV210
2312 static struct s3c24xx_serial_drv_data s5pv210_serial_drv_data = {
2313 .info = &(struct s3c24xx_uart_info) {
2314 .name = "Samsung S5PV210 UART",
2315 .type = PORT_S3C6400,
2316 .has_divslot = 1,
2317 .rx_fifomask = S5PV210_UFSTAT_RXMASK,
2318 .rx_fifoshift = S5PV210_UFSTAT_RXSHIFT,
2319 .rx_fifofull = S5PV210_UFSTAT_RXFULL,
2320 .tx_fifofull = S5PV210_UFSTAT_TXFULL,
2321 .tx_fifomask = S5PV210_UFSTAT_TXMASK,
2322 .tx_fifoshift = S5PV210_UFSTAT_TXSHIFT,
2323 .def_clk_sel = S3C2410_UCON_CLKSEL0,
2324 .num_clks = 2,
2325 .clksel_mask = S5PV210_UCON_CLKMASK,
2326 .clksel_shift = S5PV210_UCON_CLKSHIFT,
2327 },
2328 .def_cfg = &(struct s3c2410_uartcfg) {
2329 .ucon = S5PV210_UCON_DEFAULT,
2330 .ufcon = S5PV210_UFCON_DEFAULT,
2331 },
2332 .fifosize = { 256, 64, 16, 16 },
2333 };
2334 #define S5PV210_SERIAL_DRV_DATA ((kernel_ulong_t)&s5pv210_serial_drv_data)
2335 #else
2336 #define S5PV210_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2337 #endif
2338
2339 #if defined(CONFIG_ARCH_EXYNOS)
2340 #define EXYNOS_COMMON_SERIAL_DRV_DATA \
2341 .info = &(struct s3c24xx_uart_info) { \
2342 .name = "Samsung Exynos UART", \
2343 .type = PORT_S3C6400, \
2344 .has_divslot = 1, \
2345 .rx_fifomask = S5PV210_UFSTAT_RXMASK, \
2346 .rx_fifoshift = S5PV210_UFSTAT_RXSHIFT, \
2347 .rx_fifofull = S5PV210_UFSTAT_RXFULL, \
2348 .tx_fifofull = S5PV210_UFSTAT_TXFULL, \
2349 .tx_fifomask = S5PV210_UFSTAT_TXMASK, \
2350 .tx_fifoshift = S5PV210_UFSTAT_TXSHIFT, \
2351 .def_clk_sel = S3C2410_UCON_CLKSEL0, \
2352 .num_clks = 1, \
2353 .clksel_mask = 0, \
2354 .clksel_shift = 0, \
2355 }, \
2356 .def_cfg = &(struct s3c2410_uartcfg) { \
2357 .ucon = S5PV210_UCON_DEFAULT, \
2358 .ufcon = S5PV210_UFCON_DEFAULT, \
2359 .has_fracval = 1, \
2360 } \
2361
2362 static struct s3c24xx_serial_drv_data exynos4210_serial_drv_data = {
2363 EXYNOS_COMMON_SERIAL_DRV_DATA,
2364 .fifosize = { 256, 64, 16, 16 },
2365 };
2366
2367 static struct s3c24xx_serial_drv_data exynos5433_serial_drv_data = {
2368 EXYNOS_COMMON_SERIAL_DRV_DATA,
2369 .fifosize = { 64, 256, 16, 256 },
2370 };
2371
2372 #define EXYNOS4210_SERIAL_DRV_DATA ((kernel_ulong_t)&exynos4210_serial_drv_data)
2373 #define EXYNOS5433_SERIAL_DRV_DATA ((kernel_ulong_t)&exynos5433_serial_drv_data)
2374 #else
2375 #define EXYNOS4210_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2376 #define EXYNOS5433_SERIAL_DRV_DATA (kernel_ulong_t)NULL
2377 #endif
2378
2379 static const struct platform_device_id s3c24xx_serial_driver_ids[] = {
2380 {
2381 .name = "s3c2410-uart",
2382 .driver_data = S3C2410_SERIAL_DRV_DATA,
2383 }, {
2384 .name = "s3c2412-uart",
2385 .driver_data = S3C2412_SERIAL_DRV_DATA,
2386 }, {
2387 .name = "s3c2440-uart",
2388 .driver_data = S3C2440_SERIAL_DRV_DATA,
2389 }, {
2390 .name = "s3c6400-uart",
2391 .driver_data = S3C6400_SERIAL_DRV_DATA,
2392 }, {
2393 .name = "s5pv210-uart",
2394 .driver_data = S5PV210_SERIAL_DRV_DATA,
2395 }, {
2396 .name = "exynos4210-uart",
2397 .driver_data = EXYNOS4210_SERIAL_DRV_DATA,
2398 }, {
2399 .name = "exynos5433-uart",
2400 .driver_data = EXYNOS5433_SERIAL_DRV_DATA,
2401 },
2402 { },
2403 };
2404 MODULE_DEVICE_TABLE(platform, s3c24xx_serial_driver_ids);
2405
2406 #ifdef CONFIG_OF
2407 static const struct of_device_id s3c24xx_uart_dt_match[] = {
2408 { .compatible = "samsung,s3c2410-uart",
2409 .data = (void *)S3C2410_SERIAL_DRV_DATA },
2410 { .compatible = "samsung,s3c2412-uart",
2411 .data = (void *)S3C2412_SERIAL_DRV_DATA },
2412 { .compatible = "samsung,s3c2440-uart",
2413 .data = (void *)S3C2440_SERIAL_DRV_DATA },
2414 { .compatible = "samsung,s3c6400-uart",
2415 .data = (void *)S3C6400_SERIAL_DRV_DATA },
2416 { .compatible = "samsung,s5pv210-uart",
2417 .data = (void *)S5PV210_SERIAL_DRV_DATA },
2418 { .compatible = "samsung,exynos4210-uart",
2419 .data = (void *)EXYNOS4210_SERIAL_DRV_DATA },
2420 { .compatible = "samsung,exynos5433-uart",
2421 .data = (void *)EXYNOS5433_SERIAL_DRV_DATA },
2422 {},
2423 };
2424 MODULE_DEVICE_TABLE(of, s3c24xx_uart_dt_match);
2425 #endif
2426
2427 static struct platform_driver samsung_serial_driver = {
2428 .probe = s3c24xx_serial_probe,
2429 .remove = s3c24xx_serial_remove,
2430 .id_table = s3c24xx_serial_driver_ids,
2431 .driver = {
2432 .name = "samsung-uart",
2433 .pm = SERIAL_SAMSUNG_PM_OPS,
2434 .of_match_table = of_match_ptr(s3c24xx_uart_dt_match),
2435 },
2436 };
2437
2438 module_platform_driver(samsung_serial_driver);
2439
2440 #ifdef CONFIG_SERIAL_SAMSUNG_CONSOLE
2441 /*
2442 * Early console.
2443 */
2444
2445 struct samsung_early_console_data {
2446 u32 txfull_mask;
2447 };
2448
samsung_early_busyuart(struct uart_port * port)2449 static void samsung_early_busyuart(struct uart_port *port)
2450 {
2451 while (!(readl(port->membase + S3C2410_UTRSTAT) & S3C2410_UTRSTAT_TXFE))
2452 ;
2453 }
2454
samsung_early_busyuart_fifo(struct uart_port * port)2455 static void samsung_early_busyuart_fifo(struct uart_port *port)
2456 {
2457 struct samsung_early_console_data *data = port->private_data;
2458
2459 while (readl(port->membase + S3C2410_UFSTAT) & data->txfull_mask)
2460 ;
2461 }
2462
samsung_early_putc(struct uart_port * port,int c)2463 static void samsung_early_putc(struct uart_port *port, int c)
2464 {
2465 if (readl(port->membase + S3C2410_UFCON) & S3C2410_UFCON_FIFOMODE)
2466 samsung_early_busyuart_fifo(port);
2467 else
2468 samsung_early_busyuart(port);
2469
2470 writeb(c, port->membase + S3C2410_UTXH);
2471 }
2472
samsung_early_write(struct console * con,const char * s,unsigned n)2473 static void samsung_early_write(struct console *con, const char *s, unsigned n)
2474 {
2475 struct earlycon_device *dev = con->data;
2476
2477 uart_console_write(&dev->port, s, n, samsung_early_putc);
2478 }
2479
samsung_early_console_setup(struct earlycon_device * device,const char * opt)2480 static int __init samsung_early_console_setup(struct earlycon_device *device,
2481 const char *opt)
2482 {
2483 if (!device->port.membase)
2484 return -ENODEV;
2485
2486 device->con->write = samsung_early_write;
2487 return 0;
2488 }
2489
2490 /* S3C2410 */
2491 static struct samsung_early_console_data s3c2410_early_console_data = {
2492 .txfull_mask = S3C2410_UFSTAT_TXFULL,
2493 };
2494
s3c2410_early_console_setup(struct earlycon_device * device,const char * opt)2495 static int __init s3c2410_early_console_setup(struct earlycon_device *device,
2496 const char *opt)
2497 {
2498 device->port.private_data = &s3c2410_early_console_data;
2499 return samsung_early_console_setup(device, opt);
2500 }
2501 OF_EARLYCON_DECLARE(s3c2410, "samsung,s3c2410-uart",
2502 s3c2410_early_console_setup);
2503
2504 /* S3C2412, S3C2440, S3C64xx */
2505 static struct samsung_early_console_data s3c2440_early_console_data = {
2506 .txfull_mask = S3C2440_UFSTAT_TXFULL,
2507 };
2508
s3c2440_early_console_setup(struct earlycon_device * device,const char * opt)2509 static int __init s3c2440_early_console_setup(struct earlycon_device *device,
2510 const char *opt)
2511 {
2512 device->port.private_data = &s3c2440_early_console_data;
2513 return samsung_early_console_setup(device, opt);
2514 }
2515 OF_EARLYCON_DECLARE(s3c2412, "samsung,s3c2412-uart",
2516 s3c2440_early_console_setup);
2517 OF_EARLYCON_DECLARE(s3c2440, "samsung,s3c2440-uart",
2518 s3c2440_early_console_setup);
2519 OF_EARLYCON_DECLARE(s3c6400, "samsung,s3c6400-uart",
2520 s3c2440_early_console_setup);
2521
2522 /* S5PV210, EXYNOS */
2523 static struct samsung_early_console_data s5pv210_early_console_data = {
2524 .txfull_mask = S5PV210_UFSTAT_TXFULL,
2525 };
2526
s5pv210_early_console_setup(struct earlycon_device * device,const char * opt)2527 static int __init s5pv210_early_console_setup(struct earlycon_device *device,
2528 const char *opt)
2529 {
2530 device->port.private_data = &s5pv210_early_console_data;
2531 return samsung_early_console_setup(device, opt);
2532 }
2533 OF_EARLYCON_DECLARE(s5pv210, "samsung,s5pv210-uart",
2534 s5pv210_early_console_setup);
2535 OF_EARLYCON_DECLARE(exynos4210, "samsung,exynos4210-uart",
2536 s5pv210_early_console_setup);
2537 #endif
2538
2539 MODULE_ALIAS("platform:samsung-uart");
2540 MODULE_DESCRIPTION("Samsung SoC Serial port driver");
2541 MODULE_AUTHOR("Ben Dooks <ben@simtec.co.uk>");
2542 MODULE_LICENSE("GPL v2");
2543
