1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * NXP (Philips) SCC+++(SCN+++) serial driver
4 *
5 * Copyright (C) 2012 Alexander Shiyan <shc_work@mail.ru>
6 *
7 * Based on sc26xx.c, by Thomas Bogendörfer (tsbogend@alpha.franken.de)
8 */
9
10 #include <linux/clk.h>
11 #include <linux/delay.h>
12 #include <linux/err.h>
13 #include <linux/module.h>
14 #include <linux/mod_devicetable.h>
15 #include <linux/device.h>
16 #include <linux/console.h>
17 #include <linux/serial_core.h>
18 #include <linux/serial.h>
19 #include <linux/io.h>
20 #include <linux/tty.h>
21 #include <linux/tty_flip.h>
22 #include <linux/spinlock.h>
23 #include <linux/platform_device.h>
24 #include <linux/platform_data/serial-sccnxp.h>
25 #include <linux/regulator/consumer.h>
26
27 #define SCCNXP_NAME "uart-sccnxp"
28 #define SCCNXP_MAJOR 204
29 #define SCCNXP_MINOR 205
30
31 #define SCCNXP_MR_REG (0x00)
32 # define MR0_BAUD_NORMAL (0 << 0)
33 # define MR0_BAUD_EXT1 (1 << 0)
34 # define MR0_BAUD_EXT2 (5 << 0)
35 # define MR0_FIFO (1 << 3)
36 # define MR0_TXLVL (1 << 4)
37 # define MR1_BITS_5 (0 << 0)
38 # define MR1_BITS_6 (1 << 0)
39 # define MR1_BITS_7 (2 << 0)
40 # define MR1_BITS_8 (3 << 0)
41 # define MR1_PAR_EVN (0 << 2)
42 # define MR1_PAR_ODD (1 << 2)
43 # define MR1_PAR_NO (4 << 2)
44 # define MR2_STOP1 (7 << 0)
45 # define MR2_STOP2 (0xf << 0)
46 #define SCCNXP_SR_REG (0x01)
47 # define SR_RXRDY (1 << 0)
48 # define SR_FULL (1 << 1)
49 # define SR_TXRDY (1 << 2)
50 # define SR_TXEMT (1 << 3)
51 # define SR_OVR (1 << 4)
52 # define SR_PE (1 << 5)
53 # define SR_FE (1 << 6)
54 # define SR_BRK (1 << 7)
55 #define SCCNXP_CSR_REG (SCCNXP_SR_REG)
56 # define CSR_TIMER_MODE (0x0d)
57 #define SCCNXP_CR_REG (0x02)
58 # define CR_RX_ENABLE (1 << 0)
59 # define CR_RX_DISABLE (1 << 1)
60 # define CR_TX_ENABLE (1 << 2)
61 # define CR_TX_DISABLE (1 << 3)
62 # define CR_CMD_MRPTR1 (0x01 << 4)
63 # define CR_CMD_RX_RESET (0x02 << 4)
64 # define CR_CMD_TX_RESET (0x03 << 4)
65 # define CR_CMD_STATUS_RESET (0x04 << 4)
66 # define CR_CMD_BREAK_RESET (0x05 << 4)
67 # define CR_CMD_START_BREAK (0x06 << 4)
68 # define CR_CMD_STOP_BREAK (0x07 << 4)
69 # define CR_CMD_MRPTR0 (0x0b << 4)
70 #define SCCNXP_RHR_REG (0x03)
71 #define SCCNXP_THR_REG SCCNXP_RHR_REG
72 #define SCCNXP_IPCR_REG (0x04)
73 #define SCCNXP_ACR_REG SCCNXP_IPCR_REG
74 # define ACR_BAUD0 (0 << 7)
75 # define ACR_BAUD1 (1 << 7)
76 # define ACR_TIMER_MODE (6 << 4)
77 #define SCCNXP_ISR_REG (0x05)
78 #define SCCNXP_IMR_REG SCCNXP_ISR_REG
79 # define IMR_TXRDY (1 << 0)
80 # define IMR_RXRDY (1 << 1)
81 # define ISR_TXRDY(x) (1 << ((x * 4) + 0))
82 # define ISR_RXRDY(x) (1 << ((x * 4) + 1))
83 #define SCCNXP_CTPU_REG (0x06)
84 #define SCCNXP_CTPL_REG (0x07)
85 #define SCCNXP_IPR_REG (0x0d)
86 #define SCCNXP_OPCR_REG SCCNXP_IPR_REG
87 #define SCCNXP_SOP_REG (0x0e)
88 #define SCCNXP_START_COUNTER_REG SCCNXP_SOP_REG
89 #define SCCNXP_ROP_REG (0x0f)
90
91 /* Route helpers */
92 #define MCTRL_MASK(sig) (0xf << (sig))
93 #define MCTRL_IBIT(cfg, sig) ((((cfg) >> (sig)) & 0xf) - LINE_IP0)
94 #define MCTRL_OBIT(cfg, sig) ((((cfg) >> (sig)) & 0xf) - LINE_OP0)
95
96 #define SCCNXP_HAVE_IO 0x00000001
97 #define SCCNXP_HAVE_MR0 0x00000002
98
99 struct sccnxp_chip {
100 const char *name;
101 unsigned int nr;
102 unsigned long freq_min;
103 unsigned long freq_std;
104 unsigned long freq_max;
105 unsigned int flags;
106 unsigned int fifosize;
107 /* Time between read/write cycles */
108 unsigned int trwd;
109 };
110
111 struct sccnxp_port {
112 struct uart_driver uart;
113 struct uart_port port[SCCNXP_MAX_UARTS];
114 bool opened[SCCNXP_MAX_UARTS];
115
116 int irq;
117 u8 imr;
118
119 struct sccnxp_chip *chip;
120
121 #ifdef CONFIG_SERIAL_SCCNXP_CONSOLE
122 struct console console;
123 #endif
124
125 spinlock_t lock;
126
127 bool poll;
128 struct timer_list timer;
129
130 struct sccnxp_pdata pdata;
131
132 struct regulator *regulator;
133 };
134
135 static const struct sccnxp_chip sc2681 = {
136 .name = "SC2681",
137 .nr = 2,
138 .freq_min = 1000000,
139 .freq_std = 3686400,
140 .freq_max = 4000000,
141 .flags = SCCNXP_HAVE_IO,
142 .fifosize = 3,
143 .trwd = 200,
144 };
145
146 static const struct sccnxp_chip sc2691 = {
147 .name = "SC2691",
148 .nr = 1,
149 .freq_min = 1000000,
150 .freq_std = 3686400,
151 .freq_max = 4000000,
152 .flags = 0,
153 .fifosize = 3,
154 .trwd = 150,
155 };
156
157 static const struct sccnxp_chip sc2692 = {
158 .name = "SC2692",
159 .nr = 2,
160 .freq_min = 1000000,
161 .freq_std = 3686400,
162 .freq_max = 4000000,
163 .flags = SCCNXP_HAVE_IO,
164 .fifosize = 3,
165 .trwd = 30,
166 };
167
168 static const struct sccnxp_chip sc2891 = {
169 .name = "SC2891",
170 .nr = 1,
171 .freq_min = 100000,
172 .freq_std = 3686400,
173 .freq_max = 8000000,
174 .flags = SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0,
175 .fifosize = 16,
176 .trwd = 27,
177 };
178
179 static const struct sccnxp_chip sc2892 = {
180 .name = "SC2892",
181 .nr = 2,
182 .freq_min = 100000,
183 .freq_std = 3686400,
184 .freq_max = 8000000,
185 .flags = SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0,
186 .fifosize = 16,
187 .trwd = 17,
188 };
189
190 static const struct sccnxp_chip sc28202 = {
191 .name = "SC28202",
192 .nr = 2,
193 .freq_min = 1000000,
194 .freq_std = 14745600,
195 .freq_max = 50000000,
196 .flags = SCCNXP_HAVE_IO | SCCNXP_HAVE_MR0,
197 .fifosize = 256,
198 .trwd = 10,
199 };
200
201 static const struct sccnxp_chip sc68681 = {
202 .name = "SC68681",
203 .nr = 2,
204 .freq_min = 1000000,
205 .freq_std = 3686400,
206 .freq_max = 4000000,
207 .flags = SCCNXP_HAVE_IO,
208 .fifosize = 3,
209 .trwd = 200,
210 };
211
212 static const struct sccnxp_chip sc68692 = {
213 .name = "SC68692",
214 .nr = 2,
215 .freq_min = 1000000,
216 .freq_std = 3686400,
217 .freq_max = 4000000,
218 .flags = SCCNXP_HAVE_IO,
219 .fifosize = 3,
220 .trwd = 200,
221 };
222
sccnxp_read(struct uart_port * port,u8 reg)223 static u8 sccnxp_read(struct uart_port *port, u8 reg)
224 {
225 struct sccnxp_port *s = dev_get_drvdata(port->dev);
226 u8 ret;
227
228 ret = readb(port->membase + (reg << port->regshift));
229
230 ndelay(s->chip->trwd);
231
232 return ret;
233 }
234
sccnxp_write(struct uart_port * port,u8 reg,u8 v)235 static void sccnxp_write(struct uart_port *port, u8 reg, u8 v)
236 {
237 struct sccnxp_port *s = dev_get_drvdata(port->dev);
238
239 writeb(v, port->membase + (reg << port->regshift));
240
241 ndelay(s->chip->trwd);
242 }
243
sccnxp_port_read(struct uart_port * port,u8 reg)244 static u8 sccnxp_port_read(struct uart_port *port, u8 reg)
245 {
246 return sccnxp_read(port, (port->line << 3) + reg);
247 }
248
sccnxp_port_write(struct uart_port * port,u8 reg,u8 v)249 static void sccnxp_port_write(struct uart_port *port, u8 reg, u8 v)
250 {
251 sccnxp_write(port, (port->line << 3) + reg, v);
252 }
253
sccnxp_update_best_err(int a,int b,int * besterr)254 static int sccnxp_update_best_err(int a, int b, int *besterr)
255 {
256 int err = abs(a - b);
257
258 if (*besterr > err) {
259 *besterr = err;
260 return 0;
261 }
262
263 return 1;
264 }
265
266 static const struct {
267 u8 csr;
268 u8 acr;
269 u8 mr0;
270 int baud;
271 } baud_std[] = {
272 { 0, ACR_BAUD0, MR0_BAUD_NORMAL, 50, },
273 { 0, ACR_BAUD1, MR0_BAUD_NORMAL, 75, },
274 { 1, ACR_BAUD0, MR0_BAUD_NORMAL, 110, },
275 { 2, ACR_BAUD0, MR0_BAUD_NORMAL, 134, },
276 { 3, ACR_BAUD1, MR0_BAUD_NORMAL, 150, },
277 { 3, ACR_BAUD0, MR0_BAUD_NORMAL, 200, },
278 { 4, ACR_BAUD0, MR0_BAUD_NORMAL, 300, },
279 { 0, ACR_BAUD1, MR0_BAUD_EXT1, 450, },
280 { 1, ACR_BAUD0, MR0_BAUD_EXT2, 880, },
281 { 3, ACR_BAUD1, MR0_BAUD_EXT1, 900, },
282 { 5, ACR_BAUD0, MR0_BAUD_NORMAL, 600, },
283 { 7, ACR_BAUD0, MR0_BAUD_NORMAL, 1050, },
284 { 2, ACR_BAUD0, MR0_BAUD_EXT2, 1076, },
285 { 6, ACR_BAUD0, MR0_BAUD_NORMAL, 1200, },
286 { 10, ACR_BAUD1, MR0_BAUD_NORMAL, 1800, },
287 { 7, ACR_BAUD1, MR0_BAUD_NORMAL, 2000, },
288 { 8, ACR_BAUD0, MR0_BAUD_NORMAL, 2400, },
289 { 5, ACR_BAUD1, MR0_BAUD_EXT1, 3600, },
290 { 9, ACR_BAUD0, MR0_BAUD_NORMAL, 4800, },
291 { 10, ACR_BAUD0, MR0_BAUD_NORMAL, 7200, },
292 { 11, ACR_BAUD0, MR0_BAUD_NORMAL, 9600, },
293 { 8, ACR_BAUD0, MR0_BAUD_EXT1, 14400, },
294 { 12, ACR_BAUD1, MR0_BAUD_NORMAL, 19200, },
295 { 9, ACR_BAUD0, MR0_BAUD_EXT1, 28800, },
296 { 12, ACR_BAUD0, MR0_BAUD_NORMAL, 38400, },
297 { 11, ACR_BAUD0, MR0_BAUD_EXT1, 57600, },
298 { 12, ACR_BAUD1, MR0_BAUD_EXT1, 115200, },
299 { 12, ACR_BAUD0, MR0_BAUD_EXT1, 230400, },
300 { 0, 0, 0, 0 }
301 };
302
sccnxp_set_baud(struct uart_port * port,int baud)303 static int sccnxp_set_baud(struct uart_port *port, int baud)
304 {
305 struct sccnxp_port *s = dev_get_drvdata(port->dev);
306 int div_std, tmp_baud, bestbaud = INT_MAX, besterr = INT_MAX;
307 struct sccnxp_chip *chip = s->chip;
308 u8 i, acr = 0, csr = 0, mr0 = 0;
309
310 /* Find divisor to load to the timer preset registers */
311 div_std = DIV_ROUND_CLOSEST(port->uartclk, 2 * 16 * baud);
312 if ((div_std >= 2) && (div_std <= 0xffff)) {
313 bestbaud = DIV_ROUND_CLOSEST(port->uartclk, 2 * 16 * div_std);
314 sccnxp_update_best_err(baud, bestbaud, &besterr);
315 csr = CSR_TIMER_MODE;
316 sccnxp_port_write(port, SCCNXP_CTPU_REG, div_std >> 8);
317 sccnxp_port_write(port, SCCNXP_CTPL_REG, div_std);
318 /* Issue start timer/counter command */
319 sccnxp_port_read(port, SCCNXP_START_COUNTER_REG);
320 }
321
322 /* Find best baud from table */
323 for (i = 0; baud_std[i].baud && besterr; i++) {
324 if (baud_std[i].mr0 && !(chip->flags & SCCNXP_HAVE_MR0))
325 continue;
326 div_std = DIV_ROUND_CLOSEST(chip->freq_std, baud_std[i].baud);
327 tmp_baud = DIV_ROUND_CLOSEST(port->uartclk, div_std);
328 if (!sccnxp_update_best_err(baud, tmp_baud, &besterr)) {
329 acr = baud_std[i].acr;
330 csr = baud_std[i].csr;
331 mr0 = baud_std[i].mr0;
332 bestbaud = tmp_baud;
333 }
334 }
335
336 if (chip->flags & SCCNXP_HAVE_MR0) {
337 /* Enable FIFO, set half level for TX */
338 mr0 |= MR0_FIFO | MR0_TXLVL;
339 /* Update MR0 */
340 sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_MRPTR0);
341 sccnxp_port_write(port, SCCNXP_MR_REG, mr0);
342 }
343
344 sccnxp_port_write(port, SCCNXP_ACR_REG, acr | ACR_TIMER_MODE);
345 sccnxp_port_write(port, SCCNXP_CSR_REG, (csr << 4) | csr);
346
347 if (baud != bestbaud)
348 dev_dbg(port->dev, "Baudrate desired: %i, calculated: %i\n",
349 baud, bestbaud);
350
351 return bestbaud;
352 }
353
sccnxp_enable_irq(struct uart_port * port,int mask)354 static void sccnxp_enable_irq(struct uart_port *port, int mask)
355 {
356 struct sccnxp_port *s = dev_get_drvdata(port->dev);
357
358 s->imr |= mask << (port->line * 4);
359 sccnxp_write(port, SCCNXP_IMR_REG, s->imr);
360 }
361
sccnxp_disable_irq(struct uart_port * port,int mask)362 static void sccnxp_disable_irq(struct uart_port *port, int mask)
363 {
364 struct sccnxp_port *s = dev_get_drvdata(port->dev);
365
366 s->imr &= ~(mask << (port->line * 4));
367 sccnxp_write(port, SCCNXP_IMR_REG, s->imr);
368 }
369
sccnxp_set_bit(struct uart_port * port,int sig,int state)370 static void sccnxp_set_bit(struct uart_port *port, int sig, int state)
371 {
372 u8 bitmask;
373 struct sccnxp_port *s = dev_get_drvdata(port->dev);
374
375 if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(sig)) {
376 bitmask = 1 << MCTRL_OBIT(s->pdata.mctrl_cfg[port->line], sig);
377 if (state)
378 sccnxp_write(port, SCCNXP_SOP_REG, bitmask);
379 else
380 sccnxp_write(port, SCCNXP_ROP_REG, bitmask);
381 }
382 }
383
sccnxp_handle_rx(struct uart_port * port)384 static void sccnxp_handle_rx(struct uart_port *port)
385 {
386 u8 sr, ch, flag;
387
388 for (;;) {
389 sr = sccnxp_port_read(port, SCCNXP_SR_REG);
390 if (!(sr & SR_RXRDY))
391 break;
392 sr &= SR_PE | SR_FE | SR_OVR | SR_BRK;
393
394 ch = sccnxp_port_read(port, SCCNXP_RHR_REG);
395
396 port->icount.rx++;
397 flag = TTY_NORMAL;
398
399 if (unlikely(sr)) {
400 if (sr & SR_BRK) {
401 port->icount.brk++;
402 sccnxp_port_write(port, SCCNXP_CR_REG,
403 CR_CMD_BREAK_RESET);
404 if (uart_handle_break(port))
405 continue;
406 } else if (sr & SR_PE)
407 port->icount.parity++;
408 else if (sr & SR_FE)
409 port->icount.frame++;
410 else if (sr & SR_OVR) {
411 port->icount.overrun++;
412 sccnxp_port_write(port, SCCNXP_CR_REG,
413 CR_CMD_STATUS_RESET);
414 }
415
416 sr &= port->read_status_mask;
417 if (sr & SR_BRK)
418 flag = TTY_BREAK;
419 else if (sr & SR_PE)
420 flag = TTY_PARITY;
421 else if (sr & SR_FE)
422 flag = TTY_FRAME;
423 else if (sr & SR_OVR)
424 flag = TTY_OVERRUN;
425 }
426
427 if (uart_handle_sysrq_char(port, ch))
428 continue;
429
430 if (sr & port->ignore_status_mask)
431 continue;
432
433 uart_insert_char(port, sr, SR_OVR, ch, flag);
434 }
435
436 tty_flip_buffer_push(&port->state->port);
437 }
438
sccnxp_handle_tx(struct uart_port * port)439 static void sccnxp_handle_tx(struct uart_port *port)
440 {
441 u8 sr;
442 struct tty_port *tport = &port->state->port;
443 struct sccnxp_port *s = dev_get_drvdata(port->dev);
444
445 if (unlikely(port->x_char)) {
446 sccnxp_port_write(port, SCCNXP_THR_REG, port->x_char);
447 port->icount.tx++;
448 port->x_char = 0;
449 return;
450 }
451
452 if (kfifo_is_empty(&tport->xmit_fifo) || uart_tx_stopped(port)) {
453 /* Disable TX if FIFO is empty */
454 if (sccnxp_port_read(port, SCCNXP_SR_REG) & SR_TXEMT) {
455 sccnxp_disable_irq(port, IMR_TXRDY);
456
457 /* Set direction to input */
458 if (s->chip->flags & SCCNXP_HAVE_IO)
459 sccnxp_set_bit(port, DIR_OP, 0);
460 }
461 return;
462 }
463
464 while (1) {
465 unsigned char ch;
466
467 sr = sccnxp_port_read(port, SCCNXP_SR_REG);
468 if (!(sr & SR_TXRDY))
469 break;
470
471 if (!uart_fifo_get(port, &ch))
472 break;
473
474 sccnxp_port_write(port, SCCNXP_THR_REG, ch);
475 }
476
477 if (kfifo_len(&tport->xmit_fifo) < WAKEUP_CHARS)
478 uart_write_wakeup(port);
479 }
480
sccnxp_handle_events(struct sccnxp_port * s)481 static void sccnxp_handle_events(struct sccnxp_port *s)
482 {
483 int i;
484 u8 isr;
485
486 do {
487 isr = sccnxp_read(&s->port[0], SCCNXP_ISR_REG);
488 isr &= s->imr;
489 if (!isr)
490 break;
491
492 for (i = 0; i < s->uart.nr; i++) {
493 if (s->opened[i] && (isr & ISR_RXRDY(i)))
494 sccnxp_handle_rx(&s->port[i]);
495 if (s->opened[i] && (isr & ISR_TXRDY(i)))
496 sccnxp_handle_tx(&s->port[i]);
497 }
498 } while (1);
499 }
500
sccnxp_timer(struct timer_list * t)501 static void sccnxp_timer(struct timer_list *t)
502 {
503 struct sccnxp_port *s = from_timer(s, t, timer);
504 unsigned long flags;
505
506 spin_lock_irqsave(&s->lock, flags);
507 sccnxp_handle_events(s);
508 spin_unlock_irqrestore(&s->lock, flags);
509
510 mod_timer(&s->timer, jiffies + usecs_to_jiffies(s->pdata.poll_time_us));
511 }
512
sccnxp_ist(int irq,void * dev_id)513 static irqreturn_t sccnxp_ist(int irq, void *dev_id)
514 {
515 struct sccnxp_port *s = (struct sccnxp_port *)dev_id;
516 unsigned long flags;
517
518 spin_lock_irqsave(&s->lock, flags);
519 sccnxp_handle_events(s);
520 spin_unlock_irqrestore(&s->lock, flags);
521
522 return IRQ_HANDLED;
523 }
524
sccnxp_start_tx(struct uart_port * port)525 static void sccnxp_start_tx(struct uart_port *port)
526 {
527 struct sccnxp_port *s = dev_get_drvdata(port->dev);
528 unsigned long flags;
529
530 spin_lock_irqsave(&s->lock, flags);
531
532 /* Set direction to output */
533 if (s->chip->flags & SCCNXP_HAVE_IO)
534 sccnxp_set_bit(port, DIR_OP, 1);
535
536 sccnxp_enable_irq(port, IMR_TXRDY);
537
538 spin_unlock_irqrestore(&s->lock, flags);
539 }
540
sccnxp_stop_tx(struct uart_port * port)541 static void sccnxp_stop_tx(struct uart_port *port)
542 {
543 /* Do nothing */
544 }
545
sccnxp_stop_rx(struct uart_port * port)546 static void sccnxp_stop_rx(struct uart_port *port)
547 {
548 struct sccnxp_port *s = dev_get_drvdata(port->dev);
549 unsigned long flags;
550
551 spin_lock_irqsave(&s->lock, flags);
552 sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_DISABLE);
553 spin_unlock_irqrestore(&s->lock, flags);
554 }
555
sccnxp_tx_empty(struct uart_port * port)556 static unsigned int sccnxp_tx_empty(struct uart_port *port)
557 {
558 u8 val;
559 unsigned long flags;
560 struct sccnxp_port *s = dev_get_drvdata(port->dev);
561
562 spin_lock_irqsave(&s->lock, flags);
563 val = sccnxp_port_read(port, SCCNXP_SR_REG);
564 spin_unlock_irqrestore(&s->lock, flags);
565
566 return (val & SR_TXEMT) ? TIOCSER_TEMT : 0;
567 }
568
sccnxp_set_mctrl(struct uart_port * port,unsigned int mctrl)569 static void sccnxp_set_mctrl(struct uart_port *port, unsigned int mctrl)
570 {
571 struct sccnxp_port *s = dev_get_drvdata(port->dev);
572 unsigned long flags;
573
574 if (!(s->chip->flags & SCCNXP_HAVE_IO))
575 return;
576
577 spin_lock_irqsave(&s->lock, flags);
578
579 sccnxp_set_bit(port, DTR_OP, mctrl & TIOCM_DTR);
580 sccnxp_set_bit(port, RTS_OP, mctrl & TIOCM_RTS);
581
582 spin_unlock_irqrestore(&s->lock, flags);
583 }
584
sccnxp_get_mctrl(struct uart_port * port)585 static unsigned int sccnxp_get_mctrl(struct uart_port *port)
586 {
587 u8 bitmask, ipr;
588 unsigned long flags;
589 struct sccnxp_port *s = dev_get_drvdata(port->dev);
590 unsigned int mctrl = TIOCM_DSR | TIOCM_CTS | TIOCM_CAR;
591
592 if (!(s->chip->flags & SCCNXP_HAVE_IO))
593 return mctrl;
594
595 spin_lock_irqsave(&s->lock, flags);
596
597 ipr = ~sccnxp_read(port, SCCNXP_IPCR_REG);
598
599 if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(DSR_IP)) {
600 bitmask = 1 << MCTRL_IBIT(s->pdata.mctrl_cfg[port->line],
601 DSR_IP);
602 mctrl &= ~TIOCM_DSR;
603 mctrl |= (ipr & bitmask) ? TIOCM_DSR : 0;
604 }
605 if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(CTS_IP)) {
606 bitmask = 1 << MCTRL_IBIT(s->pdata.mctrl_cfg[port->line],
607 CTS_IP);
608 mctrl &= ~TIOCM_CTS;
609 mctrl |= (ipr & bitmask) ? TIOCM_CTS : 0;
610 }
611 if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(DCD_IP)) {
612 bitmask = 1 << MCTRL_IBIT(s->pdata.mctrl_cfg[port->line],
613 DCD_IP);
614 mctrl &= ~TIOCM_CAR;
615 mctrl |= (ipr & bitmask) ? TIOCM_CAR : 0;
616 }
617 if (s->pdata.mctrl_cfg[port->line] & MCTRL_MASK(RNG_IP)) {
618 bitmask = 1 << MCTRL_IBIT(s->pdata.mctrl_cfg[port->line],
619 RNG_IP);
620 mctrl &= ~TIOCM_RNG;
621 mctrl |= (ipr & bitmask) ? TIOCM_RNG : 0;
622 }
623
624 spin_unlock_irqrestore(&s->lock, flags);
625
626 return mctrl;
627 }
628
sccnxp_break_ctl(struct uart_port * port,int break_state)629 static void sccnxp_break_ctl(struct uart_port *port, int break_state)
630 {
631 struct sccnxp_port *s = dev_get_drvdata(port->dev);
632 unsigned long flags;
633
634 spin_lock_irqsave(&s->lock, flags);
635 sccnxp_port_write(port, SCCNXP_CR_REG, break_state ?
636 CR_CMD_START_BREAK : CR_CMD_STOP_BREAK);
637 spin_unlock_irqrestore(&s->lock, flags);
638 }
639
sccnxp_set_termios(struct uart_port * port,struct ktermios * termios,const struct ktermios * old)640 static void sccnxp_set_termios(struct uart_port *port,
641 struct ktermios *termios,
642 const struct ktermios *old)
643 {
644 struct sccnxp_port *s = dev_get_drvdata(port->dev);
645 unsigned long flags;
646 u8 mr1, mr2;
647 int baud;
648
649 spin_lock_irqsave(&s->lock, flags);
650
651 /* Mask termios capabilities we don't support */
652 termios->c_cflag &= ~CMSPAR;
653
654 /* Disable RX & TX, reset break condition, status and FIFOs */
655 sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_RX_RESET |
656 CR_RX_DISABLE | CR_TX_DISABLE);
657 sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_TX_RESET);
658 sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_STATUS_RESET);
659 sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_BREAK_RESET);
660
661 /* Word size */
662 switch (termios->c_cflag & CSIZE) {
663 case CS5:
664 mr1 = MR1_BITS_5;
665 break;
666 case CS6:
667 mr1 = MR1_BITS_6;
668 break;
669 case CS7:
670 mr1 = MR1_BITS_7;
671 break;
672 case CS8:
673 default:
674 mr1 = MR1_BITS_8;
675 break;
676 }
677
678 /* Parity */
679 if (termios->c_cflag & PARENB) {
680 if (termios->c_cflag & PARODD)
681 mr1 |= MR1_PAR_ODD;
682 } else
683 mr1 |= MR1_PAR_NO;
684
685 /* Stop bits */
686 mr2 = (termios->c_cflag & CSTOPB) ? MR2_STOP2 : MR2_STOP1;
687
688 /* Update desired format */
689 sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_MRPTR1);
690 sccnxp_port_write(port, SCCNXP_MR_REG, mr1);
691 sccnxp_port_write(port, SCCNXP_MR_REG, mr2);
692
693 /* Set read status mask */
694 port->read_status_mask = SR_OVR;
695 if (termios->c_iflag & INPCK)
696 port->read_status_mask |= SR_PE | SR_FE;
697 if (termios->c_iflag & (IGNBRK | BRKINT | PARMRK))
698 port->read_status_mask |= SR_BRK;
699
700 /* Set status ignore mask */
701 port->ignore_status_mask = 0;
702 if (termios->c_iflag & IGNBRK)
703 port->ignore_status_mask |= SR_BRK;
704 if (termios->c_iflag & IGNPAR)
705 port->ignore_status_mask |= SR_PE;
706 if (!(termios->c_cflag & CREAD))
707 port->ignore_status_mask |= SR_PE | SR_OVR | SR_FE | SR_BRK;
708
709 /* Setup baudrate */
710 baud = uart_get_baud_rate(port, termios, old, 50,
711 (s->chip->flags & SCCNXP_HAVE_MR0) ?
712 230400 : 38400);
713 baud = sccnxp_set_baud(port, baud);
714
715 /* Update timeout according to new baud rate */
716 uart_update_timeout(port, termios->c_cflag, baud);
717
718 /* Report actual baudrate back to core */
719 if (tty_termios_baud_rate(termios))
720 tty_termios_encode_baud_rate(termios, baud, baud);
721
722 /* Enable RX & TX */
723 sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_ENABLE | CR_TX_ENABLE);
724
725 spin_unlock_irqrestore(&s->lock, flags);
726 }
727
sccnxp_startup(struct uart_port * port)728 static int sccnxp_startup(struct uart_port *port)
729 {
730 struct sccnxp_port *s = dev_get_drvdata(port->dev);
731 unsigned long flags;
732
733 spin_lock_irqsave(&s->lock, flags);
734
735 if (s->chip->flags & SCCNXP_HAVE_IO) {
736 /* Outputs are controlled manually */
737 sccnxp_write(port, SCCNXP_OPCR_REG, 0);
738 }
739
740 /* Reset break condition, status and FIFOs */
741 sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_RX_RESET);
742 sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_TX_RESET);
743 sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_STATUS_RESET);
744 sccnxp_port_write(port, SCCNXP_CR_REG, CR_CMD_BREAK_RESET);
745
746 /* Enable RX & TX */
747 sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_ENABLE | CR_TX_ENABLE);
748
749 /* Enable RX interrupt */
750 sccnxp_enable_irq(port, IMR_RXRDY);
751
752 s->opened[port->line] = 1;
753
754 spin_unlock_irqrestore(&s->lock, flags);
755
756 return 0;
757 }
758
sccnxp_shutdown(struct uart_port * port)759 static void sccnxp_shutdown(struct uart_port *port)
760 {
761 struct sccnxp_port *s = dev_get_drvdata(port->dev);
762 unsigned long flags;
763
764 spin_lock_irqsave(&s->lock, flags);
765
766 s->opened[port->line] = 0;
767
768 /* Disable interrupts */
769 sccnxp_disable_irq(port, IMR_TXRDY | IMR_RXRDY);
770
771 /* Disable TX & RX */
772 sccnxp_port_write(port, SCCNXP_CR_REG, CR_RX_DISABLE | CR_TX_DISABLE);
773
774 /* Leave direction to input */
775 if (s->chip->flags & SCCNXP_HAVE_IO)
776 sccnxp_set_bit(port, DIR_OP, 0);
777
778 spin_unlock_irqrestore(&s->lock, flags);
779 }
780
sccnxp_type(struct uart_port * port)781 static const char *sccnxp_type(struct uart_port *port)
782 {
783 struct sccnxp_port *s = dev_get_drvdata(port->dev);
784
785 return (port->type == PORT_SC26XX) ? s->chip->name : NULL;
786 }
787
sccnxp_release_port(struct uart_port * port)788 static void sccnxp_release_port(struct uart_port *port)
789 {
790 /* Do nothing */
791 }
792
sccnxp_request_port(struct uart_port * port)793 static int sccnxp_request_port(struct uart_port *port)
794 {
795 /* Do nothing */
796 return 0;
797 }
798
sccnxp_config_port(struct uart_port * port,int flags)799 static void sccnxp_config_port(struct uart_port *port, int flags)
800 {
801 if (flags & UART_CONFIG_TYPE)
802 port->type = PORT_SC26XX;
803 }
804
sccnxp_verify_port(struct uart_port * port,struct serial_struct * s)805 static int sccnxp_verify_port(struct uart_port *port, struct serial_struct *s)
806 {
807 if ((s->type == PORT_UNKNOWN) || (s->type == PORT_SC26XX))
808 return 0;
809 if (s->irq == port->irq)
810 return 0;
811
812 return -EINVAL;
813 }
814
815 static const struct uart_ops sccnxp_ops = {
816 .tx_empty = sccnxp_tx_empty,
817 .set_mctrl = sccnxp_set_mctrl,
818 .get_mctrl = sccnxp_get_mctrl,
819 .stop_tx = sccnxp_stop_tx,
820 .start_tx = sccnxp_start_tx,
821 .stop_rx = sccnxp_stop_rx,
822 .break_ctl = sccnxp_break_ctl,
823 .startup = sccnxp_startup,
824 .shutdown = sccnxp_shutdown,
825 .set_termios = sccnxp_set_termios,
826 .type = sccnxp_type,
827 .release_port = sccnxp_release_port,
828 .request_port = sccnxp_request_port,
829 .config_port = sccnxp_config_port,
830 .verify_port = sccnxp_verify_port,
831 };
832
833 #ifdef CONFIG_SERIAL_SCCNXP_CONSOLE
sccnxp_console_putchar(struct uart_port * port,unsigned char c)834 static void sccnxp_console_putchar(struct uart_port *port, unsigned char c)
835 {
836 int tryes = 100000;
837
838 while (tryes--) {
839 if (sccnxp_port_read(port, SCCNXP_SR_REG) & SR_TXRDY) {
840 sccnxp_port_write(port, SCCNXP_THR_REG, c);
841 break;
842 }
843 barrier();
844 }
845 }
846
sccnxp_console_write(struct console * co,const char * c,unsigned n)847 static void sccnxp_console_write(struct console *co, const char *c, unsigned n)
848 {
849 struct sccnxp_port *s = (struct sccnxp_port *)co->data;
850 struct uart_port *port = &s->port[co->index];
851 unsigned long flags;
852
853 spin_lock_irqsave(&s->lock, flags);
854 uart_console_write(port, c, n, sccnxp_console_putchar);
855 spin_unlock_irqrestore(&s->lock, flags);
856 }
857
sccnxp_console_setup(struct console * co,char * options)858 static int sccnxp_console_setup(struct console *co, char *options)
859 {
860 struct sccnxp_port *s = (struct sccnxp_port *)co->data;
861 struct uart_port *port = &s->port[(co->index > 0) ? co->index : 0];
862 int baud = 9600, bits = 8, parity = 'n', flow = 'n';
863
864 if (options)
865 uart_parse_options(options, &baud, &parity, &bits, &flow);
866
867 return uart_set_options(port, co, baud, parity, bits, flow);
868 }
869 #endif
870
871 static const struct platform_device_id sccnxp_id_table[] = {
872 { .name = "sc2681", .driver_data = (kernel_ulong_t)&sc2681, },
873 { .name = "sc2691", .driver_data = (kernel_ulong_t)&sc2691, },
874 { .name = "sc2692", .driver_data = (kernel_ulong_t)&sc2692, },
875 { .name = "sc2891", .driver_data = (kernel_ulong_t)&sc2891, },
876 { .name = "sc2892", .driver_data = (kernel_ulong_t)&sc2892, },
877 { .name = "sc28202", .driver_data = (kernel_ulong_t)&sc28202, },
878 { .name = "sc68681", .driver_data = (kernel_ulong_t)&sc68681, },
879 { .name = "sc68692", .driver_data = (kernel_ulong_t)&sc68692, },
880 { }
881 };
882 MODULE_DEVICE_TABLE(platform, sccnxp_id_table);
883
sccnxp_probe(struct platform_device * pdev)884 static int sccnxp_probe(struct platform_device *pdev)
885 {
886 struct sccnxp_pdata *pdata = dev_get_platdata(&pdev->dev);
887 struct resource *res;
888 int i, ret, uartclk;
889 struct sccnxp_port *s;
890 void __iomem *membase;
891 struct clk *clk;
892
893 membase = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
894 if (IS_ERR(membase))
895 return PTR_ERR(membase);
896
897 s = devm_kzalloc(&pdev->dev, sizeof(struct sccnxp_port), GFP_KERNEL);
898 if (!s) {
899 dev_err(&pdev->dev, "Error allocating port structure\n");
900 return -ENOMEM;
901 }
902 platform_set_drvdata(pdev, s);
903
904 spin_lock_init(&s->lock);
905
906 s->chip = (struct sccnxp_chip *)pdev->id_entry->driver_data;
907
908 s->regulator = devm_regulator_get(&pdev->dev, "vcc");
909 if (!IS_ERR(s->regulator)) {
910 ret = regulator_enable(s->regulator);
911 if (ret) {
912 dev_err(&pdev->dev,
913 "Failed to enable regulator: %i\n", ret);
914 return ret;
915 }
916 } else if (PTR_ERR(s->regulator) == -EPROBE_DEFER)
917 return -EPROBE_DEFER;
918
919 clk = devm_clk_get_enabled(&pdev->dev, NULL);
920 if (IS_ERR(clk)) {
921 ret = PTR_ERR(clk);
922 if (ret == -EPROBE_DEFER)
923 goto err_out;
924 uartclk = 0;
925 } else {
926 uartclk = clk_get_rate(clk);
927 }
928
929 if (!uartclk) {
930 dev_notice(&pdev->dev, "Using default clock frequency\n");
931 uartclk = s->chip->freq_std;
932 }
933
934 /* Check input frequency */
935 if ((uartclk < s->chip->freq_min) || (uartclk > s->chip->freq_max)) {
936 dev_err(&pdev->dev, "Frequency out of bounds\n");
937 ret = -EINVAL;
938 goto err_out;
939 }
940
941 if (pdata)
942 memcpy(&s->pdata, pdata, sizeof(struct sccnxp_pdata));
943
944 if (s->pdata.poll_time_us) {
945 dev_info(&pdev->dev, "Using poll mode, resolution %u usecs\n",
946 s->pdata.poll_time_us);
947 s->poll = 1;
948 }
949
950 if (!s->poll) {
951 s->irq = platform_get_irq(pdev, 0);
952 if (s->irq < 0) {
953 ret = -ENXIO;
954 goto err_out;
955 }
956 }
957
958 s->uart.owner = THIS_MODULE;
959 s->uart.dev_name = "ttySC";
960 s->uart.major = SCCNXP_MAJOR;
961 s->uart.minor = SCCNXP_MINOR;
962 s->uart.nr = s->chip->nr;
963 #ifdef CONFIG_SERIAL_SCCNXP_CONSOLE
964 s->uart.cons = &s->console;
965 s->uart.cons->device = uart_console_device;
966 s->uart.cons->write = sccnxp_console_write;
967 s->uart.cons->setup = sccnxp_console_setup;
968 s->uart.cons->flags = CON_PRINTBUFFER;
969 s->uart.cons->index = -1;
970 s->uart.cons->data = s;
971 strcpy(s->uart.cons->name, "ttySC");
972 #endif
973 ret = uart_register_driver(&s->uart);
974 if (ret) {
975 dev_err(&pdev->dev, "Registering UART driver failed\n");
976 goto err_out;
977 }
978
979 for (i = 0; i < s->uart.nr; i++) {
980 s->port[i].line = i;
981 s->port[i].dev = &pdev->dev;
982 s->port[i].irq = s->irq;
983 s->port[i].type = PORT_SC26XX;
984 s->port[i].fifosize = s->chip->fifosize;
985 s->port[i].flags = UPF_SKIP_TEST | UPF_FIXED_TYPE;
986 s->port[i].iotype = UPIO_MEM;
987 s->port[i].mapbase = res->start;
988 s->port[i].membase = membase;
989 s->port[i].regshift = s->pdata.reg_shift;
990 s->port[i].uartclk = uartclk;
991 s->port[i].ops = &sccnxp_ops;
992 s->port[i].has_sysrq = IS_ENABLED(CONFIG_SERIAL_SCCNXP_CONSOLE);
993 uart_add_one_port(&s->uart, &s->port[i]);
994 /* Set direction to input */
995 if (s->chip->flags & SCCNXP_HAVE_IO)
996 sccnxp_set_bit(&s->port[i], DIR_OP, 0);
997 }
998
999 /* Disable interrupts */
1000 s->imr = 0;
1001 sccnxp_write(&s->port[0], SCCNXP_IMR_REG, 0);
1002
1003 if (!s->poll) {
1004 ret = devm_request_threaded_irq(&pdev->dev, s->irq, NULL,
1005 sccnxp_ist,
1006 IRQF_TRIGGER_FALLING |
1007 IRQF_ONESHOT,
1008 dev_name(&pdev->dev), s);
1009 if (!ret)
1010 return 0;
1011
1012 dev_err(&pdev->dev, "Unable to reguest IRQ %i\n", s->irq);
1013 } else {
1014 timer_setup(&s->timer, sccnxp_timer, 0);
1015 mod_timer(&s->timer, jiffies +
1016 usecs_to_jiffies(s->pdata.poll_time_us));
1017 return 0;
1018 }
1019
1020 uart_unregister_driver(&s->uart);
1021 err_out:
1022 if (!IS_ERR(s->regulator))
1023 regulator_disable(s->regulator);
1024
1025 return ret;
1026 }
1027
sccnxp_remove(struct platform_device * pdev)1028 static void sccnxp_remove(struct platform_device *pdev)
1029 {
1030 int i;
1031 struct sccnxp_port *s = platform_get_drvdata(pdev);
1032
1033 if (!s->poll)
1034 devm_free_irq(&pdev->dev, s->irq, s);
1035 else
1036 del_timer_sync(&s->timer);
1037
1038 for (i = 0; i < s->uart.nr; i++)
1039 uart_remove_one_port(&s->uart, &s->port[i]);
1040
1041 uart_unregister_driver(&s->uart);
1042
1043 if (!IS_ERR(s->regulator)) {
1044 int ret = regulator_disable(s->regulator);
1045 if (ret)
1046 dev_err(&pdev->dev, "Failed to disable regulator\n");
1047 }
1048 }
1049
1050 static struct platform_driver sccnxp_uart_driver = {
1051 .driver = {
1052 .name = SCCNXP_NAME,
1053 },
1054 .probe = sccnxp_probe,
1055 .remove = sccnxp_remove,
1056 .id_table = sccnxp_id_table,
1057 };
1058 module_platform_driver(sccnxp_uart_driver);
1059
1060 MODULE_LICENSE("GPL v2");
1061 MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
1062 MODULE_DESCRIPTION("SCCNXP serial driver");
1063