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1// SPDX-License-Identifier: GPL-2.0+
2/*
3 * Driver for CLPS711x serial ports
4 *
5 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
6 *
7 * Copyright 1999 ARM Limited
8 * Copyright (C) 2000 Deep Blue Solutions Ltd.
9 */
10
11#include <linux/module.h>
12#include <linux/device.h>
13#include <linux/console.h>
14#include <linux/serial_core.h>
15#include <linux/serial.h>
16#include <linux/clk.h>
17#include <linux/io.h>
18#include <linux/tty.h>
19#include <linux/tty_flip.h>
20#include <linux/ioport.h>
21#include <linux/of.h>
22#include <linux/platform_device.h>
23#include <linux/regmap.h>
24
25#include <linux/mfd/syscon.h>
26#include <linux/mfd/syscon/clps711x.h>
27
28#include "serial_mctrl_gpio.h"
29
30#define UART_CLPS711X_DEVNAME "ttyCL"
31#define UART_CLPS711X_NR 2
32#define UART_CLPS711X_MAJOR 204
33#define UART_CLPS711X_MINOR 40
34
35#define UARTDR_OFFSET (0x00)
36#define UBRLCR_OFFSET (0x40)
37
38#define UARTDR_FRMERR (1 << 8)
39#define UARTDR_PARERR (1 << 9)
40#define UARTDR_OVERR (1 << 10)
41
42#define UBRLCR_BAUD_MASK ((1 << 12) - 1)
43#define UBRLCR_BREAK (1 << 12)
44#define UBRLCR_PRTEN (1 << 13)
45#define UBRLCR_EVENPRT (1 << 14)
46#define UBRLCR_XSTOP (1 << 15)
47#define UBRLCR_FIFOEN (1 << 16)
48#define UBRLCR_WRDLEN5 (0 << 17)
49#define UBRLCR_WRDLEN6 (1 << 17)
50#define UBRLCR_WRDLEN7 (2 << 17)
51#define UBRLCR_WRDLEN8 (3 << 17)
52#define UBRLCR_WRDLEN_MASK (3 << 17)
53
54struct clps711x_port {
55 struct uart_port port;
56 unsigned int tx_enabled;
57 int rx_irq;
58 struct regmap *syscon;
59 struct mctrl_gpios *gpios;
60};
61
62static struct uart_driver clps711x_uart = {
63 .owner = THIS_MODULE,
64 .driver_name = UART_CLPS711X_DEVNAME,
65 .dev_name = UART_CLPS711X_DEVNAME,
66 .major = UART_CLPS711X_MAJOR,
67 .minor = UART_CLPS711X_MINOR,
68 .nr = UART_CLPS711X_NR,
69};
70
71static void uart_clps711x_stop_tx(struct uart_port *port)
72{
73 struct clps711x_port *s = dev_get_drvdata(port->dev);
74
75 if (s->tx_enabled) {
76 disable_irq(port->irq);
77 s->tx_enabled = 0;
78 }
79}
80
81static void uart_clps711x_start_tx(struct uart_port *port)
82{
83 struct clps711x_port *s = dev_get_drvdata(port->dev);
84
85 if (!s->tx_enabled) {
86 s->tx_enabled = 1;
87 enable_irq(port->irq);
88 }
89}
90
91static irqreturn_t uart_clps711x_int_rx(int irq, void *dev_id)
92{
93 struct uart_port *port = dev_id;
94 struct clps711x_port *s = dev_get_drvdata(port->dev);
95 unsigned int status;
96 u16 ch;
97 u8 flg;
98
99 for (;;) {
100 u32 sysflg = 0;
101
102 regmap_read(s->syscon, SYSFLG_OFFSET, &sysflg);
103 if (sysflg & SYSFLG_URXFE)
104 break;
105
106 ch = readw(port->membase + UARTDR_OFFSET);
107 status = ch & (UARTDR_FRMERR | UARTDR_PARERR | UARTDR_OVERR);
108 ch &= 0xff;
109
110 port->icount.rx++;
111 flg = TTY_NORMAL;
112
113 if (unlikely(status)) {
114 if (status & UARTDR_PARERR)
115 port->icount.parity++;
116 else if (status & UARTDR_FRMERR)
117 port->icount.frame++;
118 else if (status & UARTDR_OVERR)
119 port->icount.overrun++;
120
121 status &= port->read_status_mask;
122
123 if (status & UARTDR_PARERR)
124 flg = TTY_PARITY;
125 else if (status & UARTDR_FRMERR)
126 flg = TTY_FRAME;
127 else if (status & UARTDR_OVERR)
128 flg = TTY_OVERRUN;
129 }
130
131 if (uart_handle_sysrq_char(port, ch))
132 continue;
133
134 if (status & port->ignore_status_mask)
135 continue;
136
137 uart_insert_char(port, status, UARTDR_OVERR, ch, flg);
138 }
139
140 tty_flip_buffer_push(&port->state->port);
141
142 return IRQ_HANDLED;
143}
144
145static irqreturn_t uart_clps711x_int_tx(int irq, void *dev_id)
146{
147 struct uart_port *port = dev_id;
148 struct clps711x_port *s = dev_get_drvdata(port->dev);
149 struct circ_buf *xmit = &port->state->xmit;
150
151 if (port->x_char) {
152 writew(port->x_char, port->membase + UARTDR_OFFSET);
153 port->icount.tx++;
154 port->x_char = 0;
155 return IRQ_HANDLED;
156 }
157
158 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
159 if (s->tx_enabled) {
160 disable_irq_nosync(port->irq);
161 s->tx_enabled = 0;
162 }
163 return IRQ_HANDLED;
164 }
165
166 while (!uart_circ_empty(xmit)) {
167 u32 sysflg = 0;
168
169 writew(xmit->buf[xmit->tail], port->membase + UARTDR_OFFSET);
170 uart_xmit_advance(port, 1);
171
172 regmap_read(s->syscon, SYSFLG_OFFSET, &sysflg);
173 if (sysflg & SYSFLG_UTXFF)
174 break;
175 }
176
177 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
178 uart_write_wakeup(port);
179
180 return IRQ_HANDLED;
181}
182
183static unsigned int uart_clps711x_tx_empty(struct uart_port *port)
184{
185 struct clps711x_port *s = dev_get_drvdata(port->dev);
186 u32 sysflg = 0;
187
188 regmap_read(s->syscon, SYSFLG_OFFSET, &sysflg);
189
190 return (sysflg & SYSFLG_UBUSY) ? 0 : TIOCSER_TEMT;
191}
192
193static unsigned int uart_clps711x_get_mctrl(struct uart_port *port)
194{
195 unsigned int result = TIOCM_DSR | TIOCM_CTS | TIOCM_CAR;
196 struct clps711x_port *s = dev_get_drvdata(port->dev);
197
198 return mctrl_gpio_get(s->gpios, &result);
199}
200
201static void uart_clps711x_set_mctrl(struct uart_port *port, unsigned int mctrl)
202{
203 struct clps711x_port *s = dev_get_drvdata(port->dev);
204
205 mctrl_gpio_set(s->gpios, mctrl);
206}
207
208static void uart_clps711x_break_ctl(struct uart_port *port, int break_state)
209{
210 unsigned int ubrlcr;
211
212 ubrlcr = readl(port->membase + UBRLCR_OFFSET);
213 if (break_state)
214 ubrlcr |= UBRLCR_BREAK;
215 else
216 ubrlcr &= ~UBRLCR_BREAK;
217 writel(ubrlcr, port->membase + UBRLCR_OFFSET);
218}
219
220static void uart_clps711x_set_ldisc(struct uart_port *port,
221 struct ktermios *termios)
222{
223 if (!port->line) {
224 struct clps711x_port *s = dev_get_drvdata(port->dev);
225
226 regmap_update_bits(s->syscon, SYSCON_OFFSET, SYSCON1_SIREN,
227 (termios->c_line == N_IRDA) ? SYSCON1_SIREN : 0);
228 }
229}
230
231static int uart_clps711x_startup(struct uart_port *port)
232{
233 struct clps711x_port *s = dev_get_drvdata(port->dev);
234
235 /* Disable break */
236 writel(readl(port->membase + UBRLCR_OFFSET) & ~UBRLCR_BREAK,
237 port->membase + UBRLCR_OFFSET);
238
239 /* Enable the port */
240 return regmap_update_bits(s->syscon, SYSCON_OFFSET,
241 SYSCON_UARTEN, SYSCON_UARTEN);
242}
243
244static void uart_clps711x_shutdown(struct uart_port *port)
245{
246 struct clps711x_port *s = dev_get_drvdata(port->dev);
247
248 /* Disable the port */
249 regmap_update_bits(s->syscon, SYSCON_OFFSET, SYSCON_UARTEN, 0);
250}
251
252static void uart_clps711x_set_termios(struct uart_port *port,
253 struct ktermios *termios,
254 const struct ktermios *old)
255{
256 u32 ubrlcr;
257 unsigned int baud, quot;
258
259 /* Mask termios capabilities we don't support */
260 termios->c_cflag &= ~CMSPAR;
261 termios->c_iflag &= ~(BRKINT | IGNBRK);
262
263 /* Ask the core to calculate the divisor for us */
264 baud = uart_get_baud_rate(port, termios, old, port->uartclk / 4096,
265 port->uartclk / 16);
266 quot = uart_get_divisor(port, baud);
267
268 switch (termios->c_cflag & CSIZE) {
269 case CS5:
270 ubrlcr = UBRLCR_WRDLEN5;
271 break;
272 case CS6:
273 ubrlcr = UBRLCR_WRDLEN6;
274 break;
275 case CS7:
276 ubrlcr = UBRLCR_WRDLEN7;
277 break;
278 case CS8:
279 default:
280 ubrlcr = UBRLCR_WRDLEN8;
281 break;
282 }
283
284 if (termios->c_cflag & CSTOPB)
285 ubrlcr |= UBRLCR_XSTOP;
286
287 if (termios->c_cflag & PARENB) {
288 ubrlcr |= UBRLCR_PRTEN;
289 if (!(termios->c_cflag & PARODD))
290 ubrlcr |= UBRLCR_EVENPRT;
291 }
292
293 /* Enable FIFO */
294 ubrlcr |= UBRLCR_FIFOEN;
295
296 /* Set read status mask */
297 port->read_status_mask = UARTDR_OVERR;
298 if (termios->c_iflag & INPCK)
299 port->read_status_mask |= UARTDR_PARERR | UARTDR_FRMERR;
300
301 /* Set status ignore mask */
302 port->ignore_status_mask = 0;
303 if (!(termios->c_cflag & CREAD))
304 port->ignore_status_mask |= UARTDR_OVERR | UARTDR_PARERR |
305 UARTDR_FRMERR;
306
307 uart_update_timeout(port, termios->c_cflag, baud);
308
309 writel(ubrlcr | (quot - 1), port->membase + UBRLCR_OFFSET);
310}
311
312static const char *uart_clps711x_type(struct uart_port *port)
313{
314 return (port->type == PORT_CLPS711X) ? "CLPS711X" : NULL;
315}
316
317static void uart_clps711x_config_port(struct uart_port *port, int flags)
318{
319 if (flags & UART_CONFIG_TYPE)
320 port->type = PORT_CLPS711X;
321}
322
323static void uart_clps711x_nop_void(struct uart_port *port)
324{
325}
326
327static int uart_clps711x_nop_int(struct uart_port *port)
328{
329 return 0;
330}
331
332static const struct uart_ops uart_clps711x_ops = {
333 .tx_empty = uart_clps711x_tx_empty,
334 .set_mctrl = uart_clps711x_set_mctrl,
335 .get_mctrl = uart_clps711x_get_mctrl,
336 .stop_tx = uart_clps711x_stop_tx,
337 .start_tx = uart_clps711x_start_tx,
338 .stop_rx = uart_clps711x_nop_void,
339 .break_ctl = uart_clps711x_break_ctl,
340 .set_ldisc = uart_clps711x_set_ldisc,
341 .startup = uart_clps711x_startup,
342 .shutdown = uart_clps711x_shutdown,
343 .set_termios = uart_clps711x_set_termios,
344 .type = uart_clps711x_type,
345 .config_port = uart_clps711x_config_port,
346 .release_port = uart_clps711x_nop_void,
347 .request_port = uart_clps711x_nop_int,
348};
349
350#ifdef CONFIG_SERIAL_CLPS711X_CONSOLE
351static void uart_clps711x_console_putchar(struct uart_port *port, unsigned char ch)
352{
353 struct clps711x_port *s = dev_get_drvdata(port->dev);
354 u32 sysflg = 0;
355
356 /* Wait for FIFO is not full */
357 do {
358 regmap_read(s->syscon, SYSFLG_OFFSET, &sysflg);
359 } while (sysflg & SYSFLG_UTXFF);
360
361 writew(ch, port->membase + UARTDR_OFFSET);
362}
363
364static void uart_clps711x_console_write(struct console *co, const char *c,
365 unsigned n)
366{
367 struct uart_port *port = clps711x_uart.state[co->index].uart_port;
368 struct clps711x_port *s = dev_get_drvdata(port->dev);
369 u32 sysflg = 0;
370
371 uart_console_write(port, c, n, uart_clps711x_console_putchar);
372
373 /* Wait for transmitter to become empty */
374 do {
375 regmap_read(s->syscon, SYSFLG_OFFSET, &sysflg);
376 } while (sysflg & SYSFLG_UBUSY);
377}
378
379static int uart_clps711x_console_setup(struct console *co, char *options)
380{
381 int baud = 38400, bits = 8, parity = 'n', flow = 'n';
382 int ret, index = co->index;
383 struct clps711x_port *s;
384 struct uart_port *port;
385 unsigned int quot;
386 u32 ubrlcr;
387
388 if (index < 0 || index >= UART_CLPS711X_NR)
389 return -EINVAL;
390
391 port = clps711x_uart.state[index].uart_port;
392 if (!port)
393 return -ENODEV;
394
395 s = dev_get_drvdata(port->dev);
396
397 if (!options) {
398 u32 syscon = 0;
399
400 regmap_read(s->syscon, SYSCON_OFFSET, &syscon);
401 if (syscon & SYSCON_UARTEN) {
402 ubrlcr = readl(port->membase + UBRLCR_OFFSET);
403
404 if (ubrlcr & UBRLCR_PRTEN) {
405 if (ubrlcr & UBRLCR_EVENPRT)
406 parity = 'e';
407 else
408 parity = 'o';
409 }
410
411 if ((ubrlcr & UBRLCR_WRDLEN_MASK) == UBRLCR_WRDLEN7)
412 bits = 7;
413
414 quot = ubrlcr & UBRLCR_BAUD_MASK;
415 baud = port->uartclk / (16 * (quot + 1));
416 }
417 } else
418 uart_parse_options(options, &baud, &parity, &bits, &flow);
419
420 ret = uart_set_options(port, co, baud, parity, bits, flow);
421 if (ret)
422 return ret;
423
424 return regmap_update_bits(s->syscon, SYSCON_OFFSET,
425 SYSCON_UARTEN, SYSCON_UARTEN);
426}
427
428static struct console clps711x_console = {
429 .name = UART_CLPS711X_DEVNAME,
430 .device = uart_console_device,
431 .write = uart_clps711x_console_write,
432 .setup = uart_clps711x_console_setup,
433 .flags = CON_PRINTBUFFER,
434 .index = -1,
435};
436#endif
437
438static int uart_clps711x_probe(struct platform_device *pdev)
439{
440 struct device_node *np = pdev->dev.of_node;
441 struct clps711x_port *s;
442 struct resource *res;
443 struct clk *uart_clk;
444 int irq, ret;
445
446 s = devm_kzalloc(&pdev->dev, sizeof(*s), GFP_KERNEL);
447 if (!s)
448 return -ENOMEM;
449
450 uart_clk = devm_clk_get(&pdev->dev, NULL);
451 if (IS_ERR(uart_clk))
452 return PTR_ERR(uart_clk);
453
454 s->port.membase = devm_platform_get_and_ioremap_resource(pdev, 0, &res);
455 if (IS_ERR(s->port.membase))
456 return PTR_ERR(s->port.membase);
457
458 irq = platform_get_irq(pdev, 0);
459 if (irq < 0)
460 return irq;
461 s->port.irq = irq;
462
463 s->rx_irq = platform_get_irq(pdev, 1);
464 if (s->rx_irq < 0)
465 return s->rx_irq;
466
467 s->syscon = syscon_regmap_lookup_by_phandle(np, "syscon");
468 if (IS_ERR(s->syscon))
469 return PTR_ERR(s->syscon);
470
471 s->port.line = of_alias_get_id(np, "serial");
472 s->port.dev = &pdev->dev;
473 s->port.iotype = UPIO_MEM32;
474 s->port.mapbase = res->start;
475 s->port.type = PORT_CLPS711X;
476 s->port.fifosize = 16;
477 s->port.has_sysrq = IS_ENABLED(CONFIG_SERIAL_CLPS711X_CONSOLE);
478 s->port.flags = UPF_SKIP_TEST | UPF_FIXED_TYPE;
479 s->port.uartclk = clk_get_rate(uart_clk);
480 s->port.ops = &uart_clps711x_ops;
481
482 platform_set_drvdata(pdev, s);
483
484 s->gpios = mctrl_gpio_init_noauto(&pdev->dev, 0);
485 if (IS_ERR(s->gpios))
486 return PTR_ERR(s->gpios);
487
488 ret = uart_add_one_port(&clps711x_uart, &s->port);
489 if (ret)
490 return ret;
491
492 /* Disable port */
493 if (!uart_console(&s->port))
494 regmap_update_bits(s->syscon, SYSCON_OFFSET, SYSCON_UARTEN, 0);
495
496 s->tx_enabled = 1;
497
498 ret = devm_request_irq(&pdev->dev, s->port.irq, uart_clps711x_int_tx, 0,
499 dev_name(&pdev->dev), &s->port);
500 if (ret) {
501 uart_remove_one_port(&clps711x_uart, &s->port);
502 return ret;
503 }
504
505 ret = devm_request_irq(&pdev->dev, s->rx_irq, uart_clps711x_int_rx, 0,
506 dev_name(&pdev->dev), &s->port);
507 if (ret)
508 uart_remove_one_port(&clps711x_uart, &s->port);
509
510 return ret;
511}
512
513static void uart_clps711x_remove(struct platform_device *pdev)
514{
515 struct clps711x_port *s = platform_get_drvdata(pdev);
516
517 uart_remove_one_port(&clps711x_uart, &s->port);
518}
519
520static const struct of_device_id __maybe_unused clps711x_uart_dt_ids[] = {
521 { .compatible = "cirrus,ep7209-uart", },
522 { }
523};
524MODULE_DEVICE_TABLE(of, clps711x_uart_dt_ids);
525
526static struct platform_driver clps711x_uart_platform = {
527 .driver = {
528 .name = "clps711x-uart",
529 .of_match_table = of_match_ptr(clps711x_uart_dt_ids),
530 },
531 .probe = uart_clps711x_probe,
532 .remove_new = uart_clps711x_remove,
533};
534
535static int __init uart_clps711x_init(void)
536{
537 int ret;
538
539#ifdef CONFIG_SERIAL_CLPS711X_CONSOLE
540 clps711x_uart.cons = &clps711x_console;
541 clps711x_console.data = &clps711x_uart;
542#endif
543
544 ret = uart_register_driver(&clps711x_uart);
545 if (ret)
546 return ret;
547
548 return platform_driver_register(&clps711x_uart_platform);
549}
550module_init(uart_clps711x_init);
551
552static void __exit uart_clps711x_exit(void)
553{
554 platform_driver_unregister(&clps711x_uart_platform);
555 uart_unregister_driver(&clps711x_uart);
556}
557module_exit(uart_clps711x_exit);
558
559MODULE_AUTHOR("Deep Blue Solutions Ltd");
560MODULE_DESCRIPTION("CLPS711X serial driver");
561MODULE_LICENSE("GPL");
1/*
2 * Driver for CLPS711x serial ports
3 *
4 * Based on drivers/char/serial.c, by Linus Torvalds, Theodore Ts'o.
5 *
6 * Copyright 1999 ARM Limited
7 * Copyright (C) 2000 Deep Blue Solutions Ltd.
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 */
23
24#if defined(CONFIG_SERIAL_CLPS711X_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ)
25#define SUPPORT_SYSRQ
26#endif
27
28#include <linux/module.h>
29#include <linux/ioport.h>
30#include <linux/init.h>
31#include <linux/console.h>
32#include <linux/sysrq.h>
33#include <linux/spinlock.h>
34#include <linux/device.h>
35#include <linux/tty.h>
36#include <linux/tty_flip.h>
37#include <linux/serial_core.h>
38#include <linux/serial.h>
39#include <linux/io.h>
40
41#include <mach/hardware.h>
42#include <asm/irq.h>
43#include <asm/hardware/clps7111.h>
44
45#define UART_NR 2
46
47#define SERIAL_CLPS711X_MAJOR 204
48#define SERIAL_CLPS711X_MINOR 40
49#define SERIAL_CLPS711X_NR UART_NR
50
51/*
52 * We use the relevant SYSCON register as a base address for these ports.
53 */
54#define UBRLCR(port) ((port)->iobase + UBRLCR1 - SYSCON1)
55#define UARTDR(port) ((port)->iobase + UARTDR1 - SYSCON1)
56#define SYSFLG(port) ((port)->iobase + SYSFLG1 - SYSCON1)
57#define SYSCON(port) ((port)->iobase + SYSCON1 - SYSCON1)
58
59#define TX_IRQ(port) ((port)->irq)
60#define RX_IRQ(port) ((port)->irq + 1)
61
62#define UART_ANY_ERR (UARTDR_FRMERR | UARTDR_PARERR | UARTDR_OVERR)
63
64#define tx_enabled(port) ((port)->unused[0])
65
66static void clps711xuart_stop_tx(struct uart_port *port)
67{
68 if (tx_enabled(port)) {
69 disable_irq(TX_IRQ(port));
70 tx_enabled(port) = 0;
71 }
72}
73
74static void clps711xuart_start_tx(struct uart_port *port)
75{
76 if (!tx_enabled(port)) {
77 enable_irq(TX_IRQ(port));
78 tx_enabled(port) = 1;
79 }
80}
81
82static void clps711xuart_stop_rx(struct uart_port *port)
83{
84 disable_irq(RX_IRQ(port));
85}
86
87static void clps711xuart_enable_ms(struct uart_port *port)
88{
89}
90
91static irqreturn_t clps711xuart_int_rx(int irq, void *dev_id)
92{
93 struct uart_port *port = dev_id;
94 struct tty_struct *tty = port->state->port.tty;
95 unsigned int status, ch, flg;
96
97 status = clps_readl(SYSFLG(port));
98 while (!(status & SYSFLG_URXFE)) {
99 ch = clps_readl(UARTDR(port));
100
101 port->icount.rx++;
102
103 flg = TTY_NORMAL;
104
105 /*
106 * Note that the error handling code is
107 * out of the main execution path
108 */
109 if (unlikely(ch & UART_ANY_ERR)) {
110 if (ch & UARTDR_PARERR)
111 port->icount.parity++;
112 else if (ch & UARTDR_FRMERR)
113 port->icount.frame++;
114 if (ch & UARTDR_OVERR)
115 port->icount.overrun++;
116
117 ch &= port->read_status_mask;
118
119 if (ch & UARTDR_PARERR)
120 flg = TTY_PARITY;
121 else if (ch & UARTDR_FRMERR)
122 flg = TTY_FRAME;
123
124#ifdef SUPPORT_SYSRQ
125 port->sysrq = 0;
126#endif
127 }
128
129 if (uart_handle_sysrq_char(port, ch))
130 goto ignore_char;
131
132 /*
133 * CHECK: does overrun affect the current character?
134 * ASSUMPTION: it does not.
135 */
136 uart_insert_char(port, ch, UARTDR_OVERR, ch, flg);
137
138 ignore_char:
139 status = clps_readl(SYSFLG(port));
140 }
141 tty_flip_buffer_push(tty);
142 return IRQ_HANDLED;
143}
144
145static irqreturn_t clps711xuart_int_tx(int irq, void *dev_id)
146{
147 struct uart_port *port = dev_id;
148 struct circ_buf *xmit = &port->state->xmit;
149 int count;
150
151 if (port->x_char) {
152 clps_writel(port->x_char, UARTDR(port));
153 port->icount.tx++;
154 port->x_char = 0;
155 return IRQ_HANDLED;
156 }
157 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
158 clps711xuart_stop_tx(port);
159 return IRQ_HANDLED;
160 }
161
162 count = port->fifosize >> 1;
163 do {
164 clps_writel(xmit->buf[xmit->tail], UARTDR(port));
165 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
166 port->icount.tx++;
167 if (uart_circ_empty(xmit))
168 break;
169 } while (--count > 0);
170
171 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
172 uart_write_wakeup(port);
173
174 if (uart_circ_empty(xmit))
175 clps711xuart_stop_tx(port);
176
177 return IRQ_HANDLED;
178}
179
180static unsigned int clps711xuart_tx_empty(struct uart_port *port)
181{
182 unsigned int status = clps_readl(SYSFLG(port));
183 return status & SYSFLG_UBUSY ? 0 : TIOCSER_TEMT;
184}
185
186static unsigned int clps711xuart_get_mctrl(struct uart_port *port)
187{
188 unsigned int port_addr;
189 unsigned int result = 0;
190 unsigned int status;
191
192 port_addr = SYSFLG(port);
193 if (port_addr == SYSFLG1) {
194 status = clps_readl(SYSFLG1);
195 if (status & SYSFLG1_DCD)
196 result |= TIOCM_CAR;
197 if (status & SYSFLG1_DSR)
198 result |= TIOCM_DSR;
199 if (status & SYSFLG1_CTS)
200 result |= TIOCM_CTS;
201 }
202
203 return result;
204}
205
206static void
207clps711xuart_set_mctrl_null(struct uart_port *port, unsigned int mctrl)
208{
209}
210
211static void clps711xuart_break_ctl(struct uart_port *port, int break_state)
212{
213 unsigned long flags;
214 unsigned int ubrlcr;
215
216 spin_lock_irqsave(&port->lock, flags);
217 ubrlcr = clps_readl(UBRLCR(port));
218 if (break_state == -1)
219 ubrlcr |= UBRLCR_BREAK;
220 else
221 ubrlcr &= ~UBRLCR_BREAK;
222 clps_writel(ubrlcr, UBRLCR(port));
223 spin_unlock_irqrestore(&port->lock, flags);
224}
225
226static int clps711xuart_startup(struct uart_port *port)
227{
228 unsigned int syscon;
229 int retval;
230
231 tx_enabled(port) = 1;
232
233 /*
234 * Allocate the IRQs
235 */
236 retval = request_irq(TX_IRQ(port), clps711xuart_int_tx, 0,
237 "clps711xuart_tx", port);
238 if (retval)
239 return retval;
240
241 retval = request_irq(RX_IRQ(port), clps711xuart_int_rx, 0,
242 "clps711xuart_rx", port);
243 if (retval) {
244 free_irq(TX_IRQ(port), port);
245 return retval;
246 }
247
248 /*
249 * enable the port
250 */
251 syscon = clps_readl(SYSCON(port));
252 syscon |= SYSCON_UARTEN;
253 clps_writel(syscon, SYSCON(port));
254
255 return 0;
256}
257
258static void clps711xuart_shutdown(struct uart_port *port)
259{
260 unsigned int ubrlcr, syscon;
261
262 /*
263 * Free the interrupt
264 */
265 free_irq(TX_IRQ(port), port); /* TX interrupt */
266 free_irq(RX_IRQ(port), port); /* RX interrupt */
267
268 /*
269 * disable the port
270 */
271 syscon = clps_readl(SYSCON(port));
272 syscon &= ~SYSCON_UARTEN;
273 clps_writel(syscon, SYSCON(port));
274
275 /*
276 * disable break condition and fifos
277 */
278 ubrlcr = clps_readl(UBRLCR(port));
279 ubrlcr &= ~(UBRLCR_FIFOEN | UBRLCR_BREAK);
280 clps_writel(ubrlcr, UBRLCR(port));
281}
282
283static void
284clps711xuart_set_termios(struct uart_port *port, struct ktermios *termios,
285 struct ktermios *old)
286{
287 unsigned int ubrlcr, baud, quot;
288 unsigned long flags;
289
290 /*
291 * We don't implement CREAD.
292 */
293 termios->c_cflag |= CREAD;
294
295 /*
296 * Ask the core to calculate the divisor for us.
297 */
298 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
299 quot = uart_get_divisor(port, baud);
300
301 switch (termios->c_cflag & CSIZE) {
302 case CS5:
303 ubrlcr = UBRLCR_WRDLEN5;
304 break;
305 case CS6:
306 ubrlcr = UBRLCR_WRDLEN6;
307 break;
308 case CS7:
309 ubrlcr = UBRLCR_WRDLEN7;
310 break;
311 default: // CS8
312 ubrlcr = UBRLCR_WRDLEN8;
313 break;
314 }
315 if (termios->c_cflag & CSTOPB)
316 ubrlcr |= UBRLCR_XSTOP;
317 if (termios->c_cflag & PARENB) {
318 ubrlcr |= UBRLCR_PRTEN;
319 if (!(termios->c_cflag & PARODD))
320 ubrlcr |= UBRLCR_EVENPRT;
321 }
322 if (port->fifosize > 1)
323 ubrlcr |= UBRLCR_FIFOEN;
324
325 spin_lock_irqsave(&port->lock, flags);
326
327 /*
328 * Update the per-port timeout.
329 */
330 uart_update_timeout(port, termios->c_cflag, baud);
331
332 port->read_status_mask = UARTDR_OVERR;
333 if (termios->c_iflag & INPCK)
334 port->read_status_mask |= UARTDR_PARERR | UARTDR_FRMERR;
335
336 /*
337 * Characters to ignore
338 */
339 port->ignore_status_mask = 0;
340 if (termios->c_iflag & IGNPAR)
341 port->ignore_status_mask |= UARTDR_FRMERR | UARTDR_PARERR;
342 if (termios->c_iflag & IGNBRK) {
343 /*
344 * If we're ignoring parity and break indicators,
345 * ignore overruns to (for real raw support).
346 */
347 if (termios->c_iflag & IGNPAR)
348 port->ignore_status_mask |= UARTDR_OVERR;
349 }
350
351 quot -= 1;
352
353 clps_writel(ubrlcr | quot, UBRLCR(port));
354
355 spin_unlock_irqrestore(&port->lock, flags);
356}
357
358static const char *clps711xuart_type(struct uart_port *port)
359{
360 return port->type == PORT_CLPS711X ? "CLPS711x" : NULL;
361}
362
363/*
364 * Configure/autoconfigure the port.
365 */
366static void clps711xuart_config_port(struct uart_port *port, int flags)
367{
368 if (flags & UART_CONFIG_TYPE)
369 port->type = PORT_CLPS711X;
370}
371
372static void clps711xuart_release_port(struct uart_port *port)
373{
374}
375
376static int clps711xuart_request_port(struct uart_port *port)
377{
378 return 0;
379}
380
381static struct uart_ops clps711x_pops = {
382 .tx_empty = clps711xuart_tx_empty,
383 .set_mctrl = clps711xuart_set_mctrl_null,
384 .get_mctrl = clps711xuart_get_mctrl,
385 .stop_tx = clps711xuart_stop_tx,
386 .start_tx = clps711xuart_start_tx,
387 .stop_rx = clps711xuart_stop_rx,
388 .enable_ms = clps711xuart_enable_ms,
389 .break_ctl = clps711xuart_break_ctl,
390 .startup = clps711xuart_startup,
391 .shutdown = clps711xuart_shutdown,
392 .set_termios = clps711xuart_set_termios,
393 .type = clps711xuart_type,
394 .config_port = clps711xuart_config_port,
395 .release_port = clps711xuart_release_port,
396 .request_port = clps711xuart_request_port,
397};
398
399static struct uart_port clps711x_ports[UART_NR] = {
400 {
401 .iobase = SYSCON1,
402 .irq = IRQ_UTXINT1, /* IRQ_URXINT1, IRQ_UMSINT */
403 .uartclk = 3686400,
404 .fifosize = 16,
405 .ops = &clps711x_pops,
406 .line = 0,
407 .flags = UPF_BOOT_AUTOCONF,
408 },
409 {
410 .iobase = SYSCON2,
411 .irq = IRQ_UTXINT2, /* IRQ_URXINT2 */
412 .uartclk = 3686400,
413 .fifosize = 16,
414 .ops = &clps711x_pops,
415 .line = 1,
416 .flags = UPF_BOOT_AUTOCONF,
417 }
418};
419
420#ifdef CONFIG_SERIAL_CLPS711X_CONSOLE
421static void clps711xuart_console_putchar(struct uart_port *port, int ch)
422{
423 while (clps_readl(SYSFLG(port)) & SYSFLG_UTXFF)
424 barrier();
425 clps_writel(ch, UARTDR(port));
426}
427
428/*
429 * Print a string to the serial port trying not to disturb
430 * any possible real use of the port...
431 *
432 * The console_lock must be held when we get here.
433 *
434 * Note that this is called with interrupts already disabled
435 */
436static void
437clps711xuart_console_write(struct console *co, const char *s,
438 unsigned int count)
439{
440 struct uart_port *port = clps711x_ports + co->index;
441 unsigned int status, syscon;
442
443 /*
444 * Ensure that the port is enabled.
445 */
446 syscon = clps_readl(SYSCON(port));
447 clps_writel(syscon | SYSCON_UARTEN, SYSCON(port));
448
449 uart_console_write(port, s, count, clps711xuart_console_putchar);
450
451 /*
452 * Finally, wait for transmitter to become empty
453 * and restore the uart state.
454 */
455 do {
456 status = clps_readl(SYSFLG(port));
457 } while (status & SYSFLG_UBUSY);
458
459 clps_writel(syscon, SYSCON(port));
460}
461
462static void __init
463clps711xuart_console_get_options(struct uart_port *port, int *baud,
464 int *parity, int *bits)
465{
466 if (clps_readl(SYSCON(port)) & SYSCON_UARTEN) {
467 unsigned int ubrlcr, quot;
468
469 ubrlcr = clps_readl(UBRLCR(port));
470
471 *parity = 'n';
472 if (ubrlcr & UBRLCR_PRTEN) {
473 if (ubrlcr & UBRLCR_EVENPRT)
474 *parity = 'e';
475 else
476 *parity = 'o';
477 }
478
479 if ((ubrlcr & UBRLCR_WRDLEN_MASK) == UBRLCR_WRDLEN7)
480 *bits = 7;
481 else
482 *bits = 8;
483
484 quot = ubrlcr & UBRLCR_BAUD_MASK;
485 *baud = port->uartclk / (16 * (quot + 1));
486 }
487}
488
489static int __init clps711xuart_console_setup(struct console *co, char *options)
490{
491 struct uart_port *port;
492 int baud = 38400;
493 int bits = 8;
494 int parity = 'n';
495 int flow = 'n';
496
497 /*
498 * Check whether an invalid uart number has been specified, and
499 * if so, search for the first available port that does have
500 * console support.
501 */
502 port = uart_get_console(clps711x_ports, UART_NR, co);
503
504 if (options)
505 uart_parse_options(options, &baud, &parity, &bits, &flow);
506 else
507 clps711xuart_console_get_options(port, &baud, &parity, &bits);
508
509 return uart_set_options(port, co, baud, parity, bits, flow);
510}
511
512static struct uart_driver clps711x_reg;
513static struct console clps711x_console = {
514 .name = "ttyCL",
515 .write = clps711xuart_console_write,
516 .device = uart_console_device,
517 .setup = clps711xuart_console_setup,
518 .flags = CON_PRINTBUFFER,
519 .index = -1,
520 .data = &clps711x_reg,
521};
522
523static int __init clps711xuart_console_init(void)
524{
525 register_console(&clps711x_console);
526 return 0;
527}
528console_initcall(clps711xuart_console_init);
529
530#define CLPS711X_CONSOLE &clps711x_console
531#else
532#define CLPS711X_CONSOLE NULL
533#endif
534
535static struct uart_driver clps711x_reg = {
536 .driver_name = "ttyCL",
537 .dev_name = "ttyCL",
538 .major = SERIAL_CLPS711X_MAJOR,
539 .minor = SERIAL_CLPS711X_MINOR,
540 .nr = UART_NR,
541
542 .cons = CLPS711X_CONSOLE,
543};
544
545static int __init clps711xuart_init(void)
546{
547 int ret, i;
548
549 printk(KERN_INFO "Serial: CLPS711x driver\n");
550
551 ret = uart_register_driver(&clps711x_reg);
552 if (ret)
553 return ret;
554
555 for (i = 0; i < UART_NR; i++)
556 uart_add_one_port(&clps711x_reg, &clps711x_ports[i]);
557
558 return 0;
559}
560
561static void __exit clps711xuart_exit(void)
562{
563 int i;
564
565 for (i = 0; i < UART_NR; i++)
566 uart_remove_one_port(&clps711x_reg, &clps711x_ports[i]);
567
568 uart_unregister_driver(&clps711x_reg);
569}
570
571module_init(clps711xuart_init);
572module_exit(clps711xuart_exit);
573
574MODULE_AUTHOR("Deep Blue Solutions Ltd");
575MODULE_DESCRIPTION("CLPS-711x generic serial driver");
576MODULE_LICENSE("GPL");
577MODULE_ALIAS_CHARDEV(SERIAL_CLPS711X_MAJOR, SERIAL_CLPS711X_MINOR);