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1/*
2 * Driver for the serial port on the 21285 StrongArm-110 core logic chip.
3 *
4 * Based on drivers/char/serial.c
5 */
6#include <linux/module.h>
7#include <linux/tty.h>
8#include <linux/ioport.h>
9#include <linux/init.h>
10#include <linux/console.h>
11#include <linux/device.h>
12#include <linux/tty_flip.h>
13#include <linux/serial_core.h>
14#include <linux/serial.h>
15#include <linux/io.h>
16
17#include <asm/irq.h>
18#include <asm/mach-types.h>
19#include <asm/hardware/dec21285.h>
20#include <mach/hardware.h>
21
22#define BAUD_BASE (mem_fclk_21285/64)
23
24#define SERIAL_21285_NAME "ttyFB"
25#define SERIAL_21285_MAJOR 204
26#define SERIAL_21285_MINOR 4
27
28#define RXSTAT_DUMMY_READ 0x80000000
29#define RXSTAT_FRAME (1 << 0)
30#define RXSTAT_PARITY (1 << 1)
31#define RXSTAT_OVERRUN (1 << 2)
32#define RXSTAT_ANYERR (RXSTAT_FRAME|RXSTAT_PARITY|RXSTAT_OVERRUN)
33
34#define H_UBRLCR_BREAK (1 << 0)
35#define H_UBRLCR_PARENB (1 << 1)
36#define H_UBRLCR_PAREVN (1 << 2)
37#define H_UBRLCR_STOPB (1 << 3)
38#define H_UBRLCR_FIFO (1 << 4)
39
40static const char serial21285_name[] = "Footbridge UART";
41
42#define tx_enabled(port) ((port)->unused[0])
43#define rx_enabled(port) ((port)->unused[1])
44
45/*
46 * The documented expression for selecting the divisor is:
47 * BAUD_BASE / baud - 1
48 * However, typically BAUD_BASE is not divisible by baud, so
49 * we want to select the divisor that gives us the minimum
50 * error. Therefore, we want:
51 * int(BAUD_BASE / baud - 0.5) ->
52 * int(BAUD_BASE / baud - (baud >> 1) / baud) ->
53 * int((BAUD_BASE - (baud >> 1)) / baud)
54 */
55
56static void serial21285_stop_tx(struct uart_port *port)
57{
58 if (tx_enabled(port)) {
59 disable_irq_nosync(IRQ_CONTX);
60 tx_enabled(port) = 0;
61 }
62}
63
64static void serial21285_start_tx(struct uart_port *port)
65{
66 if (!tx_enabled(port)) {
67 enable_irq(IRQ_CONTX);
68 tx_enabled(port) = 1;
69 }
70}
71
72static void serial21285_stop_rx(struct uart_port *port)
73{
74 if (rx_enabled(port)) {
75 disable_irq_nosync(IRQ_CONRX);
76 rx_enabled(port) = 0;
77 }
78}
79
80static void serial21285_enable_ms(struct uart_port *port)
81{
82}
83
84static irqreturn_t serial21285_rx_chars(int irq, void *dev_id)
85{
86 struct uart_port *port = dev_id;
87 struct tty_struct *tty = port->state->port.tty;
88 unsigned int status, ch, flag, rxs, max_count = 256;
89
90 status = *CSR_UARTFLG;
91 while (!(status & 0x10) && max_count--) {
92 ch = *CSR_UARTDR;
93 flag = TTY_NORMAL;
94 port->icount.rx++;
95
96 rxs = *CSR_RXSTAT | RXSTAT_DUMMY_READ;
97 if (unlikely(rxs & RXSTAT_ANYERR)) {
98 if (rxs & RXSTAT_PARITY)
99 port->icount.parity++;
100 else if (rxs & RXSTAT_FRAME)
101 port->icount.frame++;
102 if (rxs & RXSTAT_OVERRUN)
103 port->icount.overrun++;
104
105 rxs &= port->read_status_mask;
106
107 if (rxs & RXSTAT_PARITY)
108 flag = TTY_PARITY;
109 else if (rxs & RXSTAT_FRAME)
110 flag = TTY_FRAME;
111 }
112
113 uart_insert_char(port, rxs, RXSTAT_OVERRUN, ch, flag);
114
115 status = *CSR_UARTFLG;
116 }
117 tty_flip_buffer_push(tty);
118
119 return IRQ_HANDLED;
120}
121
122static irqreturn_t serial21285_tx_chars(int irq, void *dev_id)
123{
124 struct uart_port *port = dev_id;
125 struct circ_buf *xmit = &port->state->xmit;
126 int count = 256;
127
128 if (port->x_char) {
129 *CSR_UARTDR = port->x_char;
130 port->icount.tx++;
131 port->x_char = 0;
132 goto out;
133 }
134 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
135 serial21285_stop_tx(port);
136 goto out;
137 }
138
139 do {
140 *CSR_UARTDR = xmit->buf[xmit->tail];
141 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
142 port->icount.tx++;
143 if (uart_circ_empty(xmit))
144 break;
145 } while (--count > 0 && !(*CSR_UARTFLG & 0x20));
146
147 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
148 uart_write_wakeup(port);
149
150 if (uart_circ_empty(xmit))
151 serial21285_stop_tx(port);
152
153 out:
154 return IRQ_HANDLED;
155}
156
157static unsigned int serial21285_tx_empty(struct uart_port *port)
158{
159 return (*CSR_UARTFLG & 8) ? 0 : TIOCSER_TEMT;
160}
161
162/* no modem control lines */
163static unsigned int serial21285_get_mctrl(struct uart_port *port)
164{
165 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
166}
167
168static void serial21285_set_mctrl(struct uart_port *port, unsigned int mctrl)
169{
170}
171
172static void serial21285_break_ctl(struct uart_port *port, int break_state)
173{
174 unsigned long flags;
175 unsigned int h_lcr;
176
177 spin_lock_irqsave(&port->lock, flags);
178 h_lcr = *CSR_H_UBRLCR;
179 if (break_state)
180 h_lcr |= H_UBRLCR_BREAK;
181 else
182 h_lcr &= ~H_UBRLCR_BREAK;
183 *CSR_H_UBRLCR = h_lcr;
184 spin_unlock_irqrestore(&port->lock, flags);
185}
186
187static int serial21285_startup(struct uart_port *port)
188{
189 int ret;
190
191 tx_enabled(port) = 1;
192 rx_enabled(port) = 1;
193
194 ret = request_irq(IRQ_CONRX, serial21285_rx_chars, 0,
195 serial21285_name, port);
196 if (ret == 0) {
197 ret = request_irq(IRQ_CONTX, serial21285_tx_chars, 0,
198 serial21285_name, port);
199 if (ret)
200 free_irq(IRQ_CONRX, port);
201 }
202
203 return ret;
204}
205
206static void serial21285_shutdown(struct uart_port *port)
207{
208 free_irq(IRQ_CONTX, port);
209 free_irq(IRQ_CONRX, port);
210}
211
212static void
213serial21285_set_termios(struct uart_port *port, struct ktermios *termios,
214 struct ktermios *old)
215{
216 unsigned long flags;
217 unsigned int baud, quot, h_lcr, b;
218
219 /*
220 * We don't support modem control lines.
221 */
222 termios->c_cflag &= ~(HUPCL | CRTSCTS | CMSPAR);
223 termios->c_cflag |= CLOCAL;
224
225 /*
226 * We don't support BREAK character recognition.
227 */
228 termios->c_iflag &= ~(IGNBRK | BRKINT);
229
230 /*
231 * Ask the core to calculate the divisor for us.
232 */
233 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
234 quot = uart_get_divisor(port, baud);
235 b = port->uartclk / (16 * quot);
236 tty_termios_encode_baud_rate(termios, b, b);
237
238 switch (termios->c_cflag & CSIZE) {
239 case CS5:
240 h_lcr = 0x00;
241 break;
242 case CS6:
243 h_lcr = 0x20;
244 break;
245 case CS7:
246 h_lcr = 0x40;
247 break;
248 default: /* CS8 */
249 h_lcr = 0x60;
250 break;
251 }
252
253 if (termios->c_cflag & CSTOPB)
254 h_lcr |= H_UBRLCR_STOPB;
255 if (termios->c_cflag & PARENB) {
256 h_lcr |= H_UBRLCR_PARENB;
257 if (!(termios->c_cflag & PARODD))
258 h_lcr |= H_UBRLCR_PAREVN;
259 }
260
261 if (port->fifosize)
262 h_lcr |= H_UBRLCR_FIFO;
263
264 spin_lock_irqsave(&port->lock, flags);
265
266 /*
267 * Update the per-port timeout.
268 */
269 uart_update_timeout(port, termios->c_cflag, baud);
270
271 /*
272 * Which character status flags are we interested in?
273 */
274 port->read_status_mask = RXSTAT_OVERRUN;
275 if (termios->c_iflag & INPCK)
276 port->read_status_mask |= RXSTAT_FRAME | RXSTAT_PARITY;
277
278 /*
279 * Which character status flags should we ignore?
280 */
281 port->ignore_status_mask = 0;
282 if (termios->c_iflag & IGNPAR)
283 port->ignore_status_mask |= RXSTAT_FRAME | RXSTAT_PARITY;
284 if (termios->c_iflag & IGNBRK && termios->c_iflag & IGNPAR)
285 port->ignore_status_mask |= RXSTAT_OVERRUN;
286
287 /*
288 * Ignore all characters if CREAD is not set.
289 */
290 if ((termios->c_cflag & CREAD) == 0)
291 port->ignore_status_mask |= RXSTAT_DUMMY_READ;
292
293 quot -= 1;
294
295 *CSR_UARTCON = 0;
296 *CSR_L_UBRLCR = quot & 0xff;
297 *CSR_M_UBRLCR = (quot >> 8) & 0x0f;
298 *CSR_H_UBRLCR = h_lcr;
299 *CSR_UARTCON = 1;
300
301 spin_unlock_irqrestore(&port->lock, flags);
302}
303
304static const char *serial21285_type(struct uart_port *port)
305{
306 return port->type == PORT_21285 ? "DC21285" : NULL;
307}
308
309static void serial21285_release_port(struct uart_port *port)
310{
311 release_mem_region(port->mapbase, 32);
312}
313
314static int serial21285_request_port(struct uart_port *port)
315{
316 return request_mem_region(port->mapbase, 32, serial21285_name)
317 != NULL ? 0 : -EBUSY;
318}
319
320static void serial21285_config_port(struct uart_port *port, int flags)
321{
322 if (flags & UART_CONFIG_TYPE && serial21285_request_port(port) == 0)
323 port->type = PORT_21285;
324}
325
326/*
327 * verify the new serial_struct (for TIOCSSERIAL).
328 */
329static int serial21285_verify_port(struct uart_port *port, struct serial_struct *ser)
330{
331 int ret = 0;
332 if (ser->type != PORT_UNKNOWN && ser->type != PORT_21285)
333 ret = -EINVAL;
334 if (ser->irq != NO_IRQ)
335 ret = -EINVAL;
336 if (ser->baud_base != port->uartclk / 16)
337 ret = -EINVAL;
338 return ret;
339}
340
341static struct uart_ops serial21285_ops = {
342 .tx_empty = serial21285_tx_empty,
343 .get_mctrl = serial21285_get_mctrl,
344 .set_mctrl = serial21285_set_mctrl,
345 .stop_tx = serial21285_stop_tx,
346 .start_tx = serial21285_start_tx,
347 .stop_rx = serial21285_stop_rx,
348 .enable_ms = serial21285_enable_ms,
349 .break_ctl = serial21285_break_ctl,
350 .startup = serial21285_startup,
351 .shutdown = serial21285_shutdown,
352 .set_termios = serial21285_set_termios,
353 .type = serial21285_type,
354 .release_port = serial21285_release_port,
355 .request_port = serial21285_request_port,
356 .config_port = serial21285_config_port,
357 .verify_port = serial21285_verify_port,
358};
359
360static struct uart_port serial21285_port = {
361 .mapbase = 0x42000160,
362 .iotype = UPIO_MEM,
363 .irq = NO_IRQ,
364 .fifosize = 16,
365 .ops = &serial21285_ops,
366 .flags = UPF_BOOT_AUTOCONF,
367};
368
369static void serial21285_setup_ports(void)
370{
371 serial21285_port.uartclk = mem_fclk_21285 / 4;
372}
373
374#ifdef CONFIG_SERIAL_21285_CONSOLE
375static void serial21285_console_putchar(struct uart_port *port, int ch)
376{
377 while (*CSR_UARTFLG & 0x20)
378 barrier();
379 *CSR_UARTDR = ch;
380}
381
382static void
383serial21285_console_write(struct console *co, const char *s,
384 unsigned int count)
385{
386 uart_console_write(&serial21285_port, s, count, serial21285_console_putchar);
387}
388
389static void __init
390serial21285_get_options(struct uart_port *port, int *baud,
391 int *parity, int *bits)
392{
393 if (*CSR_UARTCON == 1) {
394 unsigned int tmp;
395
396 tmp = *CSR_H_UBRLCR;
397 switch (tmp & 0x60) {
398 case 0x00:
399 *bits = 5;
400 break;
401 case 0x20:
402 *bits = 6;
403 break;
404 case 0x40:
405 *bits = 7;
406 break;
407 default:
408 case 0x60:
409 *bits = 8;
410 break;
411 }
412
413 if (tmp & H_UBRLCR_PARENB) {
414 *parity = 'o';
415 if (tmp & H_UBRLCR_PAREVN)
416 *parity = 'e';
417 }
418
419 tmp = *CSR_L_UBRLCR | (*CSR_M_UBRLCR << 8);
420
421 *baud = port->uartclk / (16 * (tmp + 1));
422 }
423}
424
425static int __init serial21285_console_setup(struct console *co, char *options)
426{
427 struct uart_port *port = &serial21285_port;
428 int baud = 9600;
429 int bits = 8;
430 int parity = 'n';
431 int flow = 'n';
432
433 if (machine_is_personal_server())
434 baud = 57600;
435
436 /*
437 * Check whether an invalid uart number has been specified, and
438 * if so, search for the first available port that does have
439 * console support.
440 */
441 if (options)
442 uart_parse_options(options, &baud, &parity, &bits, &flow);
443 else
444 serial21285_get_options(port, &baud, &parity, &bits);
445
446 return uart_set_options(port, co, baud, parity, bits, flow);
447}
448
449static struct uart_driver serial21285_reg;
450
451static struct console serial21285_console =
452{
453 .name = SERIAL_21285_NAME,
454 .write = serial21285_console_write,
455 .device = uart_console_device,
456 .setup = serial21285_console_setup,
457 .flags = CON_PRINTBUFFER,
458 .index = -1,
459 .data = &serial21285_reg,
460};
461
462static int __init rs285_console_init(void)
463{
464 serial21285_setup_ports();
465 register_console(&serial21285_console);
466 return 0;
467}
468console_initcall(rs285_console_init);
469
470#define SERIAL_21285_CONSOLE &serial21285_console
471#else
472#define SERIAL_21285_CONSOLE NULL
473#endif
474
475static struct uart_driver serial21285_reg = {
476 .owner = THIS_MODULE,
477 .driver_name = "ttyFB",
478 .dev_name = "ttyFB",
479 .major = SERIAL_21285_MAJOR,
480 .minor = SERIAL_21285_MINOR,
481 .nr = 1,
482 .cons = SERIAL_21285_CONSOLE,
483};
484
485static int __init serial21285_init(void)
486{
487 int ret;
488
489 printk(KERN_INFO "Serial: 21285 driver\n");
490
491 serial21285_setup_ports();
492
493 ret = uart_register_driver(&serial21285_reg);
494 if (ret == 0)
495 uart_add_one_port(&serial21285_reg, &serial21285_port);
496
497 return ret;
498}
499
500static void __exit serial21285_exit(void)
501{
502 uart_remove_one_port(&serial21285_reg, &serial21285_port);
503 uart_unregister_driver(&serial21285_reg);
504}
505
506module_init(serial21285_init);
507module_exit(serial21285_exit);
508
509MODULE_LICENSE("GPL");
510MODULE_DESCRIPTION("Intel Footbridge (21285) serial driver");
511MODULE_ALIAS_CHARDEV(SERIAL_21285_MAJOR, SERIAL_21285_MINOR);
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * Driver for the serial port on the 21285 StrongArm-110 core logic chip.
4 *
5 * Based on drivers/char/serial.c
6 */
7#include <linux/module.h>
8#include <linux/tty.h>
9#include <linux/ioport.h>
10#include <linux/init.h>
11#include <linux/console.h>
12#include <linux/device.h>
13#include <linux/tty_flip.h>
14#include <linux/serial_core.h>
15#include <linux/serial.h>
16#include <linux/io.h>
17
18#include <asm/irq.h>
19#include <asm/mach-types.h>
20#include <asm/system_info.h>
21#include <asm/hardware/dec21285.h>
22#include <mach/hardware.h>
23
24#define BAUD_BASE (mem_fclk_21285/64)
25
26#define SERIAL_21285_NAME "ttyFB"
27#define SERIAL_21285_MAJOR 204
28#define SERIAL_21285_MINOR 4
29
30#define RXSTAT_DUMMY_READ 0x80000000
31#define RXSTAT_FRAME (1 << 0)
32#define RXSTAT_PARITY (1 << 1)
33#define RXSTAT_OVERRUN (1 << 2)
34#define RXSTAT_ANYERR (RXSTAT_FRAME|RXSTAT_PARITY|RXSTAT_OVERRUN)
35
36#define H_UBRLCR_BREAK (1 << 0)
37#define H_UBRLCR_PARENB (1 << 1)
38#define H_UBRLCR_PAREVN (1 << 2)
39#define H_UBRLCR_STOPB (1 << 3)
40#define H_UBRLCR_FIFO (1 << 4)
41
42static const char serial21285_name[] = "Footbridge UART";
43
44/*
45 * We only need 2 bits of data, so instead of creating a whole structure for
46 * this, use bits of the private_data pointer of the uart port structure.
47 */
48#define tx_enabled_bit 0
49#define rx_enabled_bit 1
50
51static bool is_enabled(struct uart_port *port, int bit)
52{
53 unsigned long *private_data = (unsigned long *)&port->private_data;
54
55 if (test_bit(bit, private_data))
56 return true;
57 return false;
58}
59
60static void enable(struct uart_port *port, int bit)
61{
62 unsigned long *private_data = (unsigned long *)&port->private_data;
63
64 set_bit(bit, private_data);
65}
66
67static void disable(struct uart_port *port, int bit)
68{
69 unsigned long *private_data = (unsigned long *)&port->private_data;
70
71 clear_bit(bit, private_data);
72}
73
74#define is_tx_enabled(port) is_enabled(port, tx_enabled_bit)
75#define tx_enable(port) enable(port, tx_enabled_bit)
76#define tx_disable(port) disable(port, tx_enabled_bit)
77
78#define is_rx_enabled(port) is_enabled(port, rx_enabled_bit)
79#define rx_enable(port) enable(port, rx_enabled_bit)
80#define rx_disable(port) disable(port, rx_enabled_bit)
81
82/*
83 * The documented expression for selecting the divisor is:
84 * BAUD_BASE / baud - 1
85 * However, typically BAUD_BASE is not divisible by baud, so
86 * we want to select the divisor that gives us the minimum
87 * error. Therefore, we want:
88 * int(BAUD_BASE / baud - 0.5) ->
89 * int(BAUD_BASE / baud - (baud >> 1) / baud) ->
90 * int((BAUD_BASE - (baud >> 1)) / baud)
91 */
92
93static void serial21285_stop_tx(struct uart_port *port)
94{
95 if (is_tx_enabled(port)) {
96 disable_irq_nosync(IRQ_CONTX);
97 tx_disable(port);
98 }
99}
100
101static void serial21285_start_tx(struct uart_port *port)
102{
103 if (!is_tx_enabled(port)) {
104 enable_irq(IRQ_CONTX);
105 tx_enable(port);
106 }
107}
108
109static void serial21285_stop_rx(struct uart_port *port)
110{
111 if (is_rx_enabled(port)) {
112 disable_irq_nosync(IRQ_CONRX);
113 rx_disable(port);
114 }
115}
116
117static irqreturn_t serial21285_rx_chars(int irq, void *dev_id)
118{
119 struct uart_port *port = dev_id;
120 unsigned int status, ch, flag, rxs, max_count = 256;
121
122 status = *CSR_UARTFLG;
123 while (!(status & 0x10) && max_count--) {
124 ch = *CSR_UARTDR;
125 flag = TTY_NORMAL;
126 port->icount.rx++;
127
128 rxs = *CSR_RXSTAT | RXSTAT_DUMMY_READ;
129 if (unlikely(rxs & RXSTAT_ANYERR)) {
130 if (rxs & RXSTAT_PARITY)
131 port->icount.parity++;
132 else if (rxs & RXSTAT_FRAME)
133 port->icount.frame++;
134 if (rxs & RXSTAT_OVERRUN)
135 port->icount.overrun++;
136
137 rxs &= port->read_status_mask;
138
139 if (rxs & RXSTAT_PARITY)
140 flag = TTY_PARITY;
141 else if (rxs & RXSTAT_FRAME)
142 flag = TTY_FRAME;
143 }
144
145 uart_insert_char(port, rxs, RXSTAT_OVERRUN, ch, flag);
146
147 status = *CSR_UARTFLG;
148 }
149 tty_flip_buffer_push(&port->state->port);
150
151 return IRQ_HANDLED;
152}
153
154static irqreturn_t serial21285_tx_chars(int irq, void *dev_id)
155{
156 struct uart_port *port = dev_id;
157 struct circ_buf *xmit = &port->state->xmit;
158 int count = 256;
159
160 if (port->x_char) {
161 *CSR_UARTDR = port->x_char;
162 port->icount.tx++;
163 port->x_char = 0;
164 goto out;
165 }
166 if (uart_circ_empty(xmit) || uart_tx_stopped(port)) {
167 serial21285_stop_tx(port);
168 goto out;
169 }
170
171 do {
172 *CSR_UARTDR = xmit->buf[xmit->tail];
173 xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
174 port->icount.tx++;
175 if (uart_circ_empty(xmit))
176 break;
177 } while (--count > 0 && !(*CSR_UARTFLG & 0x20));
178
179 if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
180 uart_write_wakeup(port);
181
182 if (uart_circ_empty(xmit))
183 serial21285_stop_tx(port);
184
185 out:
186 return IRQ_HANDLED;
187}
188
189static unsigned int serial21285_tx_empty(struct uart_port *port)
190{
191 return (*CSR_UARTFLG & 8) ? 0 : TIOCSER_TEMT;
192}
193
194/* no modem control lines */
195static unsigned int serial21285_get_mctrl(struct uart_port *port)
196{
197 return TIOCM_CAR | TIOCM_DSR | TIOCM_CTS;
198}
199
200static void serial21285_set_mctrl(struct uart_port *port, unsigned int mctrl)
201{
202}
203
204static void serial21285_break_ctl(struct uart_port *port, int break_state)
205{
206 unsigned long flags;
207 unsigned int h_lcr;
208
209 spin_lock_irqsave(&port->lock, flags);
210 h_lcr = *CSR_H_UBRLCR;
211 if (break_state)
212 h_lcr |= H_UBRLCR_BREAK;
213 else
214 h_lcr &= ~H_UBRLCR_BREAK;
215 *CSR_H_UBRLCR = h_lcr;
216 spin_unlock_irqrestore(&port->lock, flags);
217}
218
219static int serial21285_startup(struct uart_port *port)
220{
221 int ret;
222
223 tx_enable(port);
224 rx_enable(port);
225
226 ret = request_irq(IRQ_CONRX, serial21285_rx_chars, 0,
227 serial21285_name, port);
228 if (ret == 0) {
229 ret = request_irq(IRQ_CONTX, serial21285_tx_chars, 0,
230 serial21285_name, port);
231 if (ret)
232 free_irq(IRQ_CONRX, port);
233 }
234
235 return ret;
236}
237
238static void serial21285_shutdown(struct uart_port *port)
239{
240 free_irq(IRQ_CONTX, port);
241 free_irq(IRQ_CONRX, port);
242}
243
244static void
245serial21285_set_termios(struct uart_port *port, struct ktermios *termios,
246 struct ktermios *old)
247{
248 unsigned long flags;
249 unsigned int baud, quot, h_lcr, b;
250
251 /*
252 * We don't support modem control lines.
253 */
254 termios->c_cflag &= ~(HUPCL | CRTSCTS | CMSPAR);
255 termios->c_cflag |= CLOCAL;
256
257 /*
258 * We don't support BREAK character recognition.
259 */
260 termios->c_iflag &= ~(IGNBRK | BRKINT);
261
262 /*
263 * Ask the core to calculate the divisor for us.
264 */
265 baud = uart_get_baud_rate(port, termios, old, 0, port->uartclk/16);
266 quot = uart_get_divisor(port, baud);
267 b = port->uartclk / (16 * quot);
268 tty_termios_encode_baud_rate(termios, b, b);
269
270 switch (termios->c_cflag & CSIZE) {
271 case CS5:
272 h_lcr = 0x00;
273 break;
274 case CS6:
275 h_lcr = 0x20;
276 break;
277 case CS7:
278 h_lcr = 0x40;
279 break;
280 default: /* CS8 */
281 h_lcr = 0x60;
282 break;
283 }
284
285 if (termios->c_cflag & CSTOPB)
286 h_lcr |= H_UBRLCR_STOPB;
287 if (termios->c_cflag & PARENB) {
288 h_lcr |= H_UBRLCR_PARENB;
289 if (!(termios->c_cflag & PARODD))
290 h_lcr |= H_UBRLCR_PAREVN;
291 }
292
293 if (port->fifosize)
294 h_lcr |= H_UBRLCR_FIFO;
295
296 spin_lock_irqsave(&port->lock, flags);
297
298 /*
299 * Update the per-port timeout.
300 */
301 uart_update_timeout(port, termios->c_cflag, baud);
302
303 /*
304 * Which character status flags are we interested in?
305 */
306 port->read_status_mask = RXSTAT_OVERRUN;
307 if (termios->c_iflag & INPCK)
308 port->read_status_mask |= RXSTAT_FRAME | RXSTAT_PARITY;
309
310 /*
311 * Which character status flags should we ignore?
312 */
313 port->ignore_status_mask = 0;
314 if (termios->c_iflag & IGNPAR)
315 port->ignore_status_mask |= RXSTAT_FRAME | RXSTAT_PARITY;
316 if (termios->c_iflag & IGNBRK && termios->c_iflag & IGNPAR)
317 port->ignore_status_mask |= RXSTAT_OVERRUN;
318
319 /*
320 * Ignore all characters if CREAD is not set.
321 */
322 if ((termios->c_cflag & CREAD) == 0)
323 port->ignore_status_mask |= RXSTAT_DUMMY_READ;
324
325 quot -= 1;
326
327 *CSR_UARTCON = 0;
328 *CSR_L_UBRLCR = quot & 0xff;
329 *CSR_M_UBRLCR = (quot >> 8) & 0x0f;
330 *CSR_H_UBRLCR = h_lcr;
331 *CSR_UARTCON = 1;
332
333 spin_unlock_irqrestore(&port->lock, flags);
334}
335
336static const char *serial21285_type(struct uart_port *port)
337{
338 return port->type == PORT_21285 ? "DC21285" : NULL;
339}
340
341static void serial21285_release_port(struct uart_port *port)
342{
343 release_mem_region(port->mapbase, 32);
344}
345
346static int serial21285_request_port(struct uart_port *port)
347{
348 return request_mem_region(port->mapbase, 32, serial21285_name)
349 != NULL ? 0 : -EBUSY;
350}
351
352static void serial21285_config_port(struct uart_port *port, int flags)
353{
354 if (flags & UART_CONFIG_TYPE && serial21285_request_port(port) == 0)
355 port->type = PORT_21285;
356}
357
358/*
359 * verify the new serial_struct (for TIOCSSERIAL).
360 */
361static int serial21285_verify_port(struct uart_port *port, struct serial_struct *ser)
362{
363 int ret = 0;
364 if (ser->type != PORT_UNKNOWN && ser->type != PORT_21285)
365 ret = -EINVAL;
366 if (ser->irq <= 0)
367 ret = -EINVAL;
368 if (ser->baud_base != port->uartclk / 16)
369 ret = -EINVAL;
370 return ret;
371}
372
373static const struct uart_ops serial21285_ops = {
374 .tx_empty = serial21285_tx_empty,
375 .get_mctrl = serial21285_get_mctrl,
376 .set_mctrl = serial21285_set_mctrl,
377 .stop_tx = serial21285_stop_tx,
378 .start_tx = serial21285_start_tx,
379 .stop_rx = serial21285_stop_rx,
380 .break_ctl = serial21285_break_ctl,
381 .startup = serial21285_startup,
382 .shutdown = serial21285_shutdown,
383 .set_termios = serial21285_set_termios,
384 .type = serial21285_type,
385 .release_port = serial21285_release_port,
386 .request_port = serial21285_request_port,
387 .config_port = serial21285_config_port,
388 .verify_port = serial21285_verify_port,
389};
390
391static struct uart_port serial21285_port = {
392 .mapbase = 0x42000160,
393 .iotype = UPIO_MEM,
394 .irq = 0,
395 .fifosize = 16,
396 .ops = &serial21285_ops,
397 .flags = UPF_BOOT_AUTOCONF,
398};
399
400static void serial21285_setup_ports(void)
401{
402 serial21285_port.uartclk = mem_fclk_21285 / 4;
403}
404
405#ifdef CONFIG_SERIAL_21285_CONSOLE
406static void serial21285_console_putchar(struct uart_port *port, int ch)
407{
408 while (*CSR_UARTFLG & 0x20)
409 barrier();
410 *CSR_UARTDR = ch;
411}
412
413static void
414serial21285_console_write(struct console *co, const char *s,
415 unsigned int count)
416{
417 uart_console_write(&serial21285_port, s, count, serial21285_console_putchar);
418}
419
420static void __init
421serial21285_get_options(struct uart_port *port, int *baud,
422 int *parity, int *bits)
423{
424 if (*CSR_UARTCON == 1) {
425 unsigned int tmp;
426
427 tmp = *CSR_H_UBRLCR;
428 switch (tmp & 0x60) {
429 case 0x00:
430 *bits = 5;
431 break;
432 case 0x20:
433 *bits = 6;
434 break;
435 case 0x40:
436 *bits = 7;
437 break;
438 default:
439 case 0x60:
440 *bits = 8;
441 break;
442 }
443
444 if (tmp & H_UBRLCR_PARENB) {
445 *parity = 'o';
446 if (tmp & H_UBRLCR_PAREVN)
447 *parity = 'e';
448 }
449
450 tmp = *CSR_L_UBRLCR | (*CSR_M_UBRLCR << 8);
451
452 *baud = port->uartclk / (16 * (tmp + 1));
453 }
454}
455
456static int __init serial21285_console_setup(struct console *co, char *options)
457{
458 struct uart_port *port = &serial21285_port;
459 int baud = 9600;
460 int bits = 8;
461 int parity = 'n';
462 int flow = 'n';
463
464 if (machine_is_personal_server())
465 baud = 57600;
466
467 /*
468 * Check whether an invalid uart number has been specified, and
469 * if so, search for the first available port that does have
470 * console support.
471 */
472 if (options)
473 uart_parse_options(options, &baud, &parity, &bits, &flow);
474 else
475 serial21285_get_options(port, &baud, &parity, &bits);
476
477 return uart_set_options(port, co, baud, parity, bits, flow);
478}
479
480static struct uart_driver serial21285_reg;
481
482static struct console serial21285_console =
483{
484 .name = SERIAL_21285_NAME,
485 .write = serial21285_console_write,
486 .device = uart_console_device,
487 .setup = serial21285_console_setup,
488 .flags = CON_PRINTBUFFER,
489 .index = -1,
490 .data = &serial21285_reg,
491};
492
493static int __init rs285_console_init(void)
494{
495 serial21285_setup_ports();
496 register_console(&serial21285_console);
497 return 0;
498}
499console_initcall(rs285_console_init);
500
501#define SERIAL_21285_CONSOLE &serial21285_console
502#else
503#define SERIAL_21285_CONSOLE NULL
504#endif
505
506static struct uart_driver serial21285_reg = {
507 .owner = THIS_MODULE,
508 .driver_name = "ttyFB",
509 .dev_name = "ttyFB",
510 .major = SERIAL_21285_MAJOR,
511 .minor = SERIAL_21285_MINOR,
512 .nr = 1,
513 .cons = SERIAL_21285_CONSOLE,
514};
515
516static int __init serial21285_init(void)
517{
518 int ret;
519
520 printk(KERN_INFO "Serial: 21285 driver\n");
521
522 serial21285_setup_ports();
523
524 ret = uart_register_driver(&serial21285_reg);
525 if (ret == 0)
526 uart_add_one_port(&serial21285_reg, &serial21285_port);
527
528 return ret;
529}
530
531static void __exit serial21285_exit(void)
532{
533 uart_remove_one_port(&serial21285_reg, &serial21285_port);
534 uart_unregister_driver(&serial21285_reg);
535}
536
537module_init(serial21285_init);
538module_exit(serial21285_exit);
539
540MODULE_LICENSE("GPL");
541MODULE_DESCRIPTION("Intel Footbridge (21285) serial driver");
542MODULE_ALIAS_CHARDEV(SERIAL_21285_MAJOR, SERIAL_21285_MINOR);