diff options
Diffstat (limited to 'drivers/serial/mpc52xx_uart.c')
-rw-r--r-- | drivers/serial/mpc52xx_uart.c | 852 |
1 files changed, 852 insertions, 0 deletions
diff --git a/drivers/serial/mpc52xx_uart.c b/drivers/serial/mpc52xx_uart.c new file mode 100644 index 000000000000..2a5cf174ca30 --- /dev/null +++ b/drivers/serial/mpc52xx_uart.c | |||
@@ -0,0 +1,852 @@ | |||
1 | /* | ||
2 | * drivers/serial/mpc52xx_uart.c | ||
3 | * | ||
4 | * Driver for the PSC of the Freescale MPC52xx PSCs configured as UARTs. | ||
5 | * | ||
6 | * FIXME According to the usermanual the status bits in the status register | ||
7 | * are only updated when the peripherals access the FIFO and not when the | ||
8 | * CPU access them. So since we use this bits to know when we stop writing | ||
9 | * and reading, they may not be updated in-time and a race condition may | ||
10 | * exists. But I haven't be able to prove this and I don't care. But if | ||
11 | * any problem arises, it might worth checking. The TX/RX FIFO Stats | ||
12 | * registers should be used in addition. | ||
13 | * Update: Actually, they seem updated ... At least the bits we use. | ||
14 | * | ||
15 | * | ||
16 | * Maintainer : Sylvain Munaut <tnt@246tNt.com> | ||
17 | * | ||
18 | * Some of the code has been inspired/copied from the 2.4 code written | ||
19 | * by Dale Farnsworth <dfarnsworth@mvista.com>. | ||
20 | * | ||
21 | * Copyright (C) 2004-2005 Sylvain Munaut <tnt@246tNt.com> | ||
22 | * Copyright (C) 2003 MontaVista, Software, Inc. | ||
23 | * | ||
24 | * This file is licensed under the terms of the GNU General Public License | ||
25 | * version 2. This program is licensed "as is" without any warranty of any | ||
26 | * kind, whether express or implied. | ||
27 | */ | ||
28 | |||
29 | /* Platform device Usage : | ||
30 | * | ||
31 | * Since PSCs can have multiple function, the correct driver for each one | ||
32 | * is selected by calling mpc52xx_match_psc_function(...). The function | ||
33 | * handled by this driver is "uart". | ||
34 | * | ||
35 | * The driver init all necessary registers to place the PSC in uart mode without | ||
36 | * DCD. However, the pin multiplexing aren't changed and should be set either | ||
37 | * by the bootloader or in the platform init code. | ||
38 | * | ||
39 | * The idx field must be equal to the PSC index ( e.g. 0 for PSC1, 1 for PSC2, | ||
40 | * and so on). So the PSC1 is mapped to /dev/ttyS0, PSC2 to /dev/ttyS1 and so | ||
41 | * on. But be warned, it's an ABSOLUTE REQUIREMENT ! This is needed mainly for | ||
42 | * the console code : without this 1:1 mapping, at early boot time, when we are | ||
43 | * parsing the kernel args console=ttyS?, we wouldn't know wich PSC it will be | ||
44 | * mapped to. | ||
45 | */ | ||
46 | |||
47 | #include <linux/config.h> | ||
48 | #include <linux/device.h> | ||
49 | #include <linux/module.h> | ||
50 | #include <linux/tty.h> | ||
51 | #include <linux/serial.h> | ||
52 | #include <linux/sysrq.h> | ||
53 | #include <linux/console.h> | ||
54 | |||
55 | #include <asm/delay.h> | ||
56 | #include <asm/io.h> | ||
57 | |||
58 | #include <asm/mpc52xx.h> | ||
59 | #include <asm/mpc52xx_psc.h> | ||
60 | |||
61 | #if defined(CONFIG_SERIAL_MPC52xx_CONSOLE) && defined(CONFIG_MAGIC_SYSRQ) | ||
62 | #define SUPPORT_SYSRQ | ||
63 | #endif | ||
64 | |||
65 | #include <linux/serial_core.h> | ||
66 | |||
67 | |||
68 | |||
69 | #define ISR_PASS_LIMIT 256 /* Max number of iteration in the interrupt */ | ||
70 | |||
71 | |||
72 | static struct uart_port mpc52xx_uart_ports[MPC52xx_PSC_MAXNUM]; | ||
73 | /* Rem: - We use the read_status_mask as a shadow of | ||
74 | * psc->mpc52xx_psc_imr | ||
75 | * - It's important that is array is all zero on start as we | ||
76 | * use it to know if it's initialized or not ! If it's not sure | ||
77 | * it's cleared, then a memset(...,0,...) should be added to | ||
78 | * the console_init | ||
79 | */ | ||
80 | |||
81 | #define PSC(port) ((struct mpc52xx_psc __iomem *)((port)->membase)) | ||
82 | |||
83 | |||
84 | /* Forward declaration of the interruption handling routine */ | ||
85 | static irqreturn_t mpc52xx_uart_int(int irq,void *dev_id,struct pt_regs *regs); | ||
86 | |||
87 | |||
88 | /* Simple macro to test if a port is console or not. This one is taken | ||
89 | * for serial_core.c and maybe should be moved to serial_core.h ? */ | ||
90 | #ifdef CONFIG_SERIAL_CORE_CONSOLE | ||
91 | #define uart_console(port) ((port)->cons && (port)->cons->index == (port)->line) | ||
92 | #else | ||
93 | #define uart_console(port) (0) | ||
94 | #endif | ||
95 | |||
96 | |||
97 | /* ======================================================================== */ | ||
98 | /* UART operations */ | ||
99 | /* ======================================================================== */ | ||
100 | |||
101 | static unsigned int | ||
102 | mpc52xx_uart_tx_empty(struct uart_port *port) | ||
103 | { | ||
104 | int status = in_be16(&PSC(port)->mpc52xx_psc_status); | ||
105 | return (status & MPC52xx_PSC_SR_TXEMP) ? TIOCSER_TEMT : 0; | ||
106 | } | ||
107 | |||
108 | static void | ||
109 | mpc52xx_uart_set_mctrl(struct uart_port *port, unsigned int mctrl) | ||
110 | { | ||
111 | /* Not implemented */ | ||
112 | } | ||
113 | |||
114 | static unsigned int | ||
115 | mpc52xx_uart_get_mctrl(struct uart_port *port) | ||
116 | { | ||
117 | /* Not implemented */ | ||
118 | return TIOCM_CTS | TIOCM_DSR | TIOCM_CAR; | ||
119 | } | ||
120 | |||
121 | static void | ||
122 | mpc52xx_uart_stop_tx(struct uart_port *port, unsigned int tty_stop) | ||
123 | { | ||
124 | /* port->lock taken by caller */ | ||
125 | port->read_status_mask &= ~MPC52xx_PSC_IMR_TXRDY; | ||
126 | out_be16(&PSC(port)->mpc52xx_psc_imr,port->read_status_mask); | ||
127 | } | ||
128 | |||
129 | static void | ||
130 | mpc52xx_uart_start_tx(struct uart_port *port, unsigned int tty_start) | ||
131 | { | ||
132 | /* port->lock taken by caller */ | ||
133 | port->read_status_mask |= MPC52xx_PSC_IMR_TXRDY; | ||
134 | out_be16(&PSC(port)->mpc52xx_psc_imr,port->read_status_mask); | ||
135 | } | ||
136 | |||
137 | static void | ||
138 | mpc52xx_uart_send_xchar(struct uart_port *port, char ch) | ||
139 | { | ||
140 | unsigned long flags; | ||
141 | spin_lock_irqsave(&port->lock, flags); | ||
142 | |||
143 | port->x_char = ch; | ||
144 | if (ch) { | ||
145 | /* Make sure tx interrupts are on */ | ||
146 | /* Truly necessary ??? They should be anyway */ | ||
147 | port->read_status_mask |= MPC52xx_PSC_IMR_TXRDY; | ||
148 | out_be16(&PSC(port)->mpc52xx_psc_imr,port->read_status_mask); | ||
149 | } | ||
150 | |||
151 | spin_unlock_irqrestore(&port->lock, flags); | ||
152 | } | ||
153 | |||
154 | static void | ||
155 | mpc52xx_uart_stop_rx(struct uart_port *port) | ||
156 | { | ||
157 | /* port->lock taken by caller */ | ||
158 | port->read_status_mask &= ~MPC52xx_PSC_IMR_RXRDY; | ||
159 | out_be16(&PSC(port)->mpc52xx_psc_imr,port->read_status_mask); | ||
160 | } | ||
161 | |||
162 | static void | ||
163 | mpc52xx_uart_enable_ms(struct uart_port *port) | ||
164 | { | ||
165 | /* Not implemented */ | ||
166 | } | ||
167 | |||
168 | static void | ||
169 | mpc52xx_uart_break_ctl(struct uart_port *port, int ctl) | ||
170 | { | ||
171 | unsigned long flags; | ||
172 | spin_lock_irqsave(&port->lock, flags); | ||
173 | |||
174 | if ( ctl == -1 ) | ||
175 | out_8(&PSC(port)->command,MPC52xx_PSC_START_BRK); | ||
176 | else | ||
177 | out_8(&PSC(port)->command,MPC52xx_PSC_STOP_BRK); | ||
178 | |||
179 | spin_unlock_irqrestore(&port->lock, flags); | ||
180 | } | ||
181 | |||
182 | static int | ||
183 | mpc52xx_uart_startup(struct uart_port *port) | ||
184 | { | ||
185 | struct mpc52xx_psc __iomem *psc = PSC(port); | ||
186 | int ret; | ||
187 | |||
188 | /* Request IRQ */ | ||
189 | ret = request_irq(port->irq, mpc52xx_uart_int, | ||
190 | SA_INTERRUPT | SA_SAMPLE_RANDOM, "mpc52xx_psc_uart", port); | ||
191 | if (ret) | ||
192 | return ret; | ||
193 | |||
194 | /* Reset/activate the port, clear and enable interrupts */ | ||
195 | out_8(&psc->command,MPC52xx_PSC_RST_RX); | ||
196 | out_8(&psc->command,MPC52xx_PSC_RST_TX); | ||
197 | |||
198 | out_be32(&psc->sicr,0); /* UART mode DCD ignored */ | ||
199 | |||
200 | out_be16(&psc->mpc52xx_psc_clock_select, 0xdd00); /* /16 prescaler on */ | ||
201 | |||
202 | out_8(&psc->rfcntl, 0x00); | ||
203 | out_be16(&psc->rfalarm, 0x1ff); | ||
204 | out_8(&psc->tfcntl, 0x07); | ||
205 | out_be16(&psc->tfalarm, 0x80); | ||
206 | |||
207 | port->read_status_mask |= MPC52xx_PSC_IMR_RXRDY | MPC52xx_PSC_IMR_TXRDY; | ||
208 | out_be16(&psc->mpc52xx_psc_imr,port->read_status_mask); | ||
209 | |||
210 | out_8(&psc->command,MPC52xx_PSC_TX_ENABLE); | ||
211 | out_8(&psc->command,MPC52xx_PSC_RX_ENABLE); | ||
212 | |||
213 | return 0; | ||
214 | } | ||
215 | |||
216 | static void | ||
217 | mpc52xx_uart_shutdown(struct uart_port *port) | ||
218 | { | ||
219 | struct mpc52xx_psc __iomem *psc = PSC(port); | ||
220 | |||
221 | /* Shut down the port, interrupt and all */ | ||
222 | out_8(&psc->command,MPC52xx_PSC_RST_RX); | ||
223 | out_8(&psc->command,MPC52xx_PSC_RST_TX); | ||
224 | |||
225 | port->read_status_mask = 0; | ||
226 | out_be16(&psc->mpc52xx_psc_imr,port->read_status_mask); | ||
227 | |||
228 | /* Release interrupt */ | ||
229 | free_irq(port->irq, port); | ||
230 | } | ||
231 | |||
232 | static void | ||
233 | mpc52xx_uart_set_termios(struct uart_port *port, struct termios *new, | ||
234 | struct termios *old) | ||
235 | { | ||
236 | struct mpc52xx_psc __iomem *psc = PSC(port); | ||
237 | unsigned long flags; | ||
238 | unsigned char mr1, mr2; | ||
239 | unsigned short ctr; | ||
240 | unsigned int j, baud, quot; | ||
241 | |||
242 | /* Prepare what we're gonna write */ | ||
243 | mr1 = 0; | ||
244 | |||
245 | switch (new->c_cflag & CSIZE) { | ||
246 | case CS5: mr1 |= MPC52xx_PSC_MODE_5_BITS; | ||
247 | break; | ||
248 | case CS6: mr1 |= MPC52xx_PSC_MODE_6_BITS; | ||
249 | break; | ||
250 | case CS7: mr1 |= MPC52xx_PSC_MODE_7_BITS; | ||
251 | break; | ||
252 | case CS8: | ||
253 | default: mr1 |= MPC52xx_PSC_MODE_8_BITS; | ||
254 | } | ||
255 | |||
256 | if (new->c_cflag & PARENB) { | ||
257 | mr1 |= (new->c_cflag & PARODD) ? | ||
258 | MPC52xx_PSC_MODE_PARODD : MPC52xx_PSC_MODE_PAREVEN; | ||
259 | } else | ||
260 | mr1 |= MPC52xx_PSC_MODE_PARNONE; | ||
261 | |||
262 | |||
263 | mr2 = 0; | ||
264 | |||
265 | if (new->c_cflag & CSTOPB) | ||
266 | mr2 |= MPC52xx_PSC_MODE_TWO_STOP; | ||
267 | else | ||
268 | mr2 |= ((new->c_cflag & CSIZE) == CS5) ? | ||
269 | MPC52xx_PSC_MODE_ONE_STOP_5_BITS : | ||
270 | MPC52xx_PSC_MODE_ONE_STOP; | ||
271 | |||
272 | |||
273 | baud = uart_get_baud_rate(port, new, old, 0, port->uartclk/16); | ||
274 | quot = uart_get_divisor(port, baud); | ||
275 | ctr = quot & 0xffff; | ||
276 | |||
277 | /* Get the lock */ | ||
278 | spin_lock_irqsave(&port->lock, flags); | ||
279 | |||
280 | /* Update the per-port timeout */ | ||
281 | uart_update_timeout(port, new->c_cflag, baud); | ||
282 | |||
283 | /* Do our best to flush TX & RX, so we don't loose anything */ | ||
284 | /* But we don't wait indefinitly ! */ | ||
285 | j = 5000000; /* Maximum wait */ | ||
286 | /* FIXME Can't receive chars since set_termios might be called at early | ||
287 | * boot for the console, all stuff is not yet ready to receive at that | ||
288 | * time and that just makes the kernel oops */ | ||
289 | /* while (j-- && mpc52xx_uart_int_rx_chars(port)); */ | ||
290 | while (!(in_be16(&psc->mpc52xx_psc_status) & MPC52xx_PSC_SR_TXEMP) && | ||
291 | --j) | ||
292 | udelay(1); | ||
293 | |||
294 | if (!j) | ||
295 | printk( KERN_ERR "mpc52xx_uart.c: " | ||
296 | "Unable to flush RX & TX fifos in-time in set_termios." | ||
297 | "Some chars may have been lost.\n" ); | ||
298 | |||
299 | /* Reset the TX & RX */ | ||
300 | out_8(&psc->command,MPC52xx_PSC_RST_RX); | ||
301 | out_8(&psc->command,MPC52xx_PSC_RST_TX); | ||
302 | |||
303 | /* Send new mode settings */ | ||
304 | out_8(&psc->command,MPC52xx_PSC_SEL_MODE_REG_1); | ||
305 | out_8(&psc->mode,mr1); | ||
306 | out_8(&psc->mode,mr2); | ||
307 | out_8(&psc->ctur,ctr >> 8); | ||
308 | out_8(&psc->ctlr,ctr & 0xff); | ||
309 | |||
310 | /* Reenable TX & RX */ | ||
311 | out_8(&psc->command,MPC52xx_PSC_TX_ENABLE); | ||
312 | out_8(&psc->command,MPC52xx_PSC_RX_ENABLE); | ||
313 | |||
314 | /* We're all set, release the lock */ | ||
315 | spin_unlock_irqrestore(&port->lock, flags); | ||
316 | } | ||
317 | |||
318 | static const char * | ||
319 | mpc52xx_uart_type(struct uart_port *port) | ||
320 | { | ||
321 | return port->type == PORT_MPC52xx ? "MPC52xx PSC" : NULL; | ||
322 | } | ||
323 | |||
324 | static void | ||
325 | mpc52xx_uart_release_port(struct uart_port *port) | ||
326 | { | ||
327 | if (port->flags & UPF_IOREMAP) { /* remapped by us ? */ | ||
328 | iounmap(port->membase); | ||
329 | port->membase = NULL; | ||
330 | } | ||
331 | |||
332 | release_mem_region(port->mapbase, MPC52xx_PSC_SIZE); | ||
333 | } | ||
334 | |||
335 | static int | ||
336 | mpc52xx_uart_request_port(struct uart_port *port) | ||
337 | { | ||
338 | if (port->flags & UPF_IOREMAP) /* Need to remap ? */ | ||
339 | port->membase = ioremap(port->mapbase, MPC52xx_PSC_SIZE); | ||
340 | |||
341 | if (!port->membase) | ||
342 | return -EINVAL; | ||
343 | |||
344 | return request_mem_region(port->mapbase, MPC52xx_PSC_SIZE, | ||
345 | "mpc52xx_psc_uart") != NULL ? 0 : -EBUSY; | ||
346 | } | ||
347 | |||
348 | static void | ||
349 | mpc52xx_uart_config_port(struct uart_port *port, int flags) | ||
350 | { | ||
351 | if ( (flags & UART_CONFIG_TYPE) && | ||
352 | (mpc52xx_uart_request_port(port) == 0) ) | ||
353 | port->type = PORT_MPC52xx; | ||
354 | } | ||
355 | |||
356 | static int | ||
357 | mpc52xx_uart_verify_port(struct uart_port *port, struct serial_struct *ser) | ||
358 | { | ||
359 | if ( ser->type != PORT_UNKNOWN && ser->type != PORT_MPC52xx ) | ||
360 | return -EINVAL; | ||
361 | |||
362 | if ( (ser->irq != port->irq) || | ||
363 | (ser->io_type != SERIAL_IO_MEM) || | ||
364 | (ser->baud_base != port->uartclk) || | ||
365 | (ser->iomem_base != (void*)port->mapbase) || | ||
366 | (ser->hub6 != 0 ) ) | ||
367 | return -EINVAL; | ||
368 | |||
369 | return 0; | ||
370 | } | ||
371 | |||
372 | |||
373 | static struct uart_ops mpc52xx_uart_ops = { | ||
374 | .tx_empty = mpc52xx_uart_tx_empty, | ||
375 | .set_mctrl = mpc52xx_uart_set_mctrl, | ||
376 | .get_mctrl = mpc52xx_uart_get_mctrl, | ||
377 | .stop_tx = mpc52xx_uart_stop_tx, | ||
378 | .start_tx = mpc52xx_uart_start_tx, | ||
379 | .send_xchar = mpc52xx_uart_send_xchar, | ||
380 | .stop_rx = mpc52xx_uart_stop_rx, | ||
381 | .enable_ms = mpc52xx_uart_enable_ms, | ||
382 | .break_ctl = mpc52xx_uart_break_ctl, | ||
383 | .startup = mpc52xx_uart_startup, | ||
384 | .shutdown = mpc52xx_uart_shutdown, | ||
385 | .set_termios = mpc52xx_uart_set_termios, | ||
386 | /* .pm = mpc52xx_uart_pm, Not supported yet */ | ||
387 | /* .set_wake = mpc52xx_uart_set_wake, Not supported yet */ | ||
388 | .type = mpc52xx_uart_type, | ||
389 | .release_port = mpc52xx_uart_release_port, | ||
390 | .request_port = mpc52xx_uart_request_port, | ||
391 | .config_port = mpc52xx_uart_config_port, | ||
392 | .verify_port = mpc52xx_uart_verify_port | ||
393 | }; | ||
394 | |||
395 | |||
396 | /* ======================================================================== */ | ||
397 | /* Interrupt handling */ | ||
398 | /* ======================================================================== */ | ||
399 | |||
400 | static inline int | ||
401 | mpc52xx_uart_int_rx_chars(struct uart_port *port, struct pt_regs *regs) | ||
402 | { | ||
403 | struct tty_struct *tty = port->info->tty; | ||
404 | unsigned char ch; | ||
405 | unsigned short status; | ||
406 | |||
407 | /* While we can read, do so ! */ | ||
408 | while ( (status = in_be16(&PSC(port)->mpc52xx_psc_status)) & | ||
409 | MPC52xx_PSC_SR_RXRDY) { | ||
410 | |||
411 | /* If we are full, just stop reading */ | ||
412 | if (tty->flip.count >= TTY_FLIPBUF_SIZE) | ||
413 | break; | ||
414 | |||
415 | /* Get the char */ | ||
416 | ch = in_8(&PSC(port)->mpc52xx_psc_buffer_8); | ||
417 | |||
418 | /* Handle sysreq char */ | ||
419 | #ifdef SUPPORT_SYSRQ | ||
420 | if (uart_handle_sysrq_char(port, ch, regs)) { | ||
421 | port->sysrq = 0; | ||
422 | continue; | ||
423 | } | ||
424 | #endif | ||
425 | |||
426 | /* Store it */ | ||
427 | *tty->flip.char_buf_ptr = ch; | ||
428 | *tty->flip.flag_buf_ptr = 0; | ||
429 | port->icount.rx++; | ||
430 | |||
431 | if ( status & (MPC52xx_PSC_SR_PE | | ||
432 | MPC52xx_PSC_SR_FE | | ||
433 | MPC52xx_PSC_SR_RB | | ||
434 | MPC52xx_PSC_SR_OE) ) { | ||
435 | |||
436 | if (status & MPC52xx_PSC_SR_RB) { | ||
437 | *tty->flip.flag_buf_ptr = TTY_BREAK; | ||
438 | uart_handle_break(port); | ||
439 | } else if (status & MPC52xx_PSC_SR_PE) | ||
440 | *tty->flip.flag_buf_ptr = TTY_PARITY; | ||
441 | else if (status & MPC52xx_PSC_SR_FE) | ||
442 | *tty->flip.flag_buf_ptr = TTY_FRAME; | ||
443 | if (status & MPC52xx_PSC_SR_OE) { | ||
444 | /* | ||
445 | * Overrun is special, since it's | ||
446 | * reported immediately, and doesn't | ||
447 | * affect the current character | ||
448 | */ | ||
449 | if (tty->flip.count < (TTY_FLIPBUF_SIZE-1)) { | ||
450 | tty->flip.flag_buf_ptr++; | ||
451 | tty->flip.char_buf_ptr++; | ||
452 | tty->flip.count++; | ||
453 | } | ||
454 | *tty->flip.flag_buf_ptr = TTY_OVERRUN; | ||
455 | } | ||
456 | |||
457 | /* Clear error condition */ | ||
458 | out_8(&PSC(port)->command,MPC52xx_PSC_RST_ERR_STAT); | ||
459 | |||
460 | } | ||
461 | |||
462 | tty->flip.char_buf_ptr++; | ||
463 | tty->flip.flag_buf_ptr++; | ||
464 | tty->flip.count++; | ||
465 | |||
466 | } | ||
467 | |||
468 | tty_flip_buffer_push(tty); | ||
469 | |||
470 | return in_be16(&PSC(port)->mpc52xx_psc_status) & MPC52xx_PSC_SR_RXRDY; | ||
471 | } | ||
472 | |||
473 | static inline int | ||
474 | mpc52xx_uart_int_tx_chars(struct uart_port *port) | ||
475 | { | ||
476 | struct circ_buf *xmit = &port->info->xmit; | ||
477 | |||
478 | /* Process out of band chars */ | ||
479 | if (port->x_char) { | ||
480 | out_8(&PSC(port)->mpc52xx_psc_buffer_8, port->x_char); | ||
481 | port->icount.tx++; | ||
482 | port->x_char = 0; | ||
483 | return 1; | ||
484 | } | ||
485 | |||
486 | /* Nothing to do ? */ | ||
487 | if (uart_circ_empty(xmit) || uart_tx_stopped(port)) { | ||
488 | mpc52xx_uart_stop_tx(port,0); | ||
489 | return 0; | ||
490 | } | ||
491 | |||
492 | /* Send chars */ | ||
493 | while (in_be16(&PSC(port)->mpc52xx_psc_status) & MPC52xx_PSC_SR_TXRDY) { | ||
494 | out_8(&PSC(port)->mpc52xx_psc_buffer_8, xmit->buf[xmit->tail]); | ||
495 | xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1); | ||
496 | port->icount.tx++; | ||
497 | if (uart_circ_empty(xmit)) | ||
498 | break; | ||
499 | } | ||
500 | |||
501 | /* Wake up */ | ||
502 | if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS) | ||
503 | uart_write_wakeup(port); | ||
504 | |||
505 | /* Maybe we're done after all */ | ||
506 | if (uart_circ_empty(xmit)) { | ||
507 | mpc52xx_uart_stop_tx(port,0); | ||
508 | return 0; | ||
509 | } | ||
510 | |||
511 | return 1; | ||
512 | } | ||
513 | |||
514 | static irqreturn_t | ||
515 | mpc52xx_uart_int(int irq, void *dev_id, struct pt_regs *regs) | ||
516 | { | ||
517 | struct uart_port *port = (struct uart_port *) dev_id; | ||
518 | unsigned long pass = ISR_PASS_LIMIT; | ||
519 | unsigned int keepgoing; | ||
520 | unsigned short status; | ||
521 | |||
522 | if ( irq != port->irq ) { | ||
523 | printk( KERN_WARNING | ||
524 | "mpc52xx_uart_int : " \ | ||
525 | "Received wrong int %d. Waiting for %d\n", | ||
526 | irq, port->irq); | ||
527 | return IRQ_NONE; | ||
528 | } | ||
529 | |||
530 | spin_lock(&port->lock); | ||
531 | |||
532 | /* While we have stuff to do, we continue */ | ||
533 | do { | ||
534 | /* If we don't find anything to do, we stop */ | ||
535 | keepgoing = 0; | ||
536 | |||
537 | /* Read status */ | ||
538 | status = in_be16(&PSC(port)->mpc52xx_psc_isr); | ||
539 | status &= port->read_status_mask; | ||
540 | |||
541 | /* Do we need to receive chars ? */ | ||
542 | /* For this RX interrupts must be on and some chars waiting */ | ||
543 | if ( status & MPC52xx_PSC_IMR_RXRDY ) | ||
544 | keepgoing |= mpc52xx_uart_int_rx_chars(port, regs); | ||
545 | |||
546 | /* Do we need to send chars ? */ | ||
547 | /* For this, TX must be ready and TX interrupt enabled */ | ||
548 | if ( status & MPC52xx_PSC_IMR_TXRDY ) | ||
549 | keepgoing |= mpc52xx_uart_int_tx_chars(port); | ||
550 | |||
551 | /* Limit number of iteration */ | ||
552 | if ( !(--pass) ) | ||
553 | keepgoing = 0; | ||
554 | |||
555 | } while (keepgoing); | ||
556 | |||
557 | spin_unlock(&port->lock); | ||
558 | |||
559 | return IRQ_HANDLED; | ||
560 | } | ||
561 | |||
562 | |||
563 | /* ======================================================================== */ | ||
564 | /* Console ( if applicable ) */ | ||
565 | /* ======================================================================== */ | ||
566 | |||
567 | #ifdef CONFIG_SERIAL_MPC52xx_CONSOLE | ||
568 | |||
569 | static void __init | ||
570 | mpc52xx_console_get_options(struct uart_port *port, | ||
571 | int *baud, int *parity, int *bits, int *flow) | ||
572 | { | ||
573 | struct mpc52xx_psc __iomem *psc = PSC(port); | ||
574 | unsigned char mr1; | ||
575 | |||
576 | /* Read the mode registers */ | ||
577 | out_8(&psc->command,MPC52xx_PSC_SEL_MODE_REG_1); | ||
578 | mr1 = in_8(&psc->mode); | ||
579 | |||
580 | /* CT{U,L}R are write-only ! */ | ||
581 | *baud = __res.bi_baudrate ? | ||
582 | __res.bi_baudrate : CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD; | ||
583 | |||
584 | /* Parse them */ | ||
585 | switch (mr1 & MPC52xx_PSC_MODE_BITS_MASK) { | ||
586 | case MPC52xx_PSC_MODE_5_BITS: *bits = 5; break; | ||
587 | case MPC52xx_PSC_MODE_6_BITS: *bits = 6; break; | ||
588 | case MPC52xx_PSC_MODE_7_BITS: *bits = 7; break; | ||
589 | case MPC52xx_PSC_MODE_8_BITS: | ||
590 | default: *bits = 8; | ||
591 | } | ||
592 | |||
593 | if (mr1 & MPC52xx_PSC_MODE_PARNONE) | ||
594 | *parity = 'n'; | ||
595 | else | ||
596 | *parity = mr1 & MPC52xx_PSC_MODE_PARODD ? 'o' : 'e'; | ||
597 | } | ||
598 | |||
599 | static void | ||
600 | mpc52xx_console_write(struct console *co, const char *s, unsigned int count) | ||
601 | { | ||
602 | struct uart_port *port = &mpc52xx_uart_ports[co->index]; | ||
603 | struct mpc52xx_psc __iomem *psc = PSC(port); | ||
604 | unsigned int i, j; | ||
605 | |||
606 | /* Disable interrupts */ | ||
607 | out_be16(&psc->mpc52xx_psc_imr, 0); | ||
608 | |||
609 | /* Wait the TX buffer to be empty */ | ||
610 | j = 5000000; /* Maximum wait */ | ||
611 | while (!(in_be16(&psc->mpc52xx_psc_status) & MPC52xx_PSC_SR_TXEMP) && | ||
612 | --j) | ||
613 | udelay(1); | ||
614 | |||
615 | /* Write all the chars */ | ||
616 | for ( i=0 ; i<count ; i++ ) { | ||
617 | |||
618 | /* Send the char */ | ||
619 | out_8(&psc->mpc52xx_psc_buffer_8, *s); | ||
620 | |||
621 | /* Line return handling */ | ||
622 | if ( *s++ == '\n' ) | ||
623 | out_8(&psc->mpc52xx_psc_buffer_8, '\r'); | ||
624 | |||
625 | /* Wait the TX buffer to be empty */ | ||
626 | j = 20000; /* Maximum wait */ | ||
627 | while (!(in_be16(&psc->mpc52xx_psc_status) & | ||
628 | MPC52xx_PSC_SR_TXEMP) && --j) | ||
629 | udelay(1); | ||
630 | } | ||
631 | |||
632 | /* Restore interrupt state */ | ||
633 | out_be16(&psc->mpc52xx_psc_imr, port->read_status_mask); | ||
634 | } | ||
635 | |||
636 | static int __init | ||
637 | mpc52xx_console_setup(struct console *co, char *options) | ||
638 | { | ||
639 | struct uart_port *port = &mpc52xx_uart_ports[co->index]; | ||
640 | |||
641 | int baud = CONFIG_SERIAL_MPC52xx_CONSOLE_BAUD; | ||
642 | int bits = 8; | ||
643 | int parity = 'n'; | ||
644 | int flow = 'n'; | ||
645 | |||
646 | if (co->index < 0 || co->index >= MPC52xx_PSC_MAXNUM) | ||
647 | return -EINVAL; | ||
648 | |||
649 | /* Basic port init. Needed since we use some uart_??? func before | ||
650 | * real init for early access */ | ||
651 | spin_lock_init(&port->lock); | ||
652 | port->uartclk = __res.bi_ipbfreq / 2; /* Look at CTLR doc */ | ||
653 | port->ops = &mpc52xx_uart_ops; | ||
654 | port->mapbase = MPC52xx_PA(MPC52xx_PSCx_OFFSET(co->index+1)); | ||
655 | |||
656 | /* We ioremap ourself */ | ||
657 | port->membase = ioremap(port->mapbase, MPC52xx_PSC_SIZE); | ||
658 | if (port->membase == NULL) | ||
659 | return -EINVAL; | ||
660 | |||
661 | /* Setup the port parameters accoding to options */ | ||
662 | if (options) | ||
663 | uart_parse_options(options, &baud, &parity, &bits, &flow); | ||
664 | else | ||
665 | mpc52xx_console_get_options(port, &baud, &parity, &bits, &flow); | ||
666 | |||
667 | return uart_set_options(port, co, baud, parity, bits, flow); | ||
668 | } | ||
669 | |||
670 | |||
671 | extern struct uart_driver mpc52xx_uart_driver; | ||
672 | |||
673 | static struct console mpc52xx_console = { | ||
674 | .name = "ttyS", | ||
675 | .write = mpc52xx_console_write, | ||
676 | .device = uart_console_device, | ||
677 | .setup = mpc52xx_console_setup, | ||
678 | .flags = CON_PRINTBUFFER, | ||
679 | .index = -1, /* Specified on the cmdline (e.g. console=ttyS0 ) */ | ||
680 | .data = &mpc52xx_uart_driver, | ||
681 | }; | ||
682 | |||
683 | |||
684 | static int __init | ||
685 | mpc52xx_console_init(void) | ||
686 | { | ||
687 | register_console(&mpc52xx_console); | ||
688 | return 0; | ||
689 | } | ||
690 | |||
691 | console_initcall(mpc52xx_console_init); | ||
692 | |||
693 | #define MPC52xx_PSC_CONSOLE &mpc52xx_console | ||
694 | #else | ||
695 | #define MPC52xx_PSC_CONSOLE NULL | ||
696 | #endif | ||
697 | |||
698 | |||
699 | /* ======================================================================== */ | ||
700 | /* UART Driver */ | ||
701 | /* ======================================================================== */ | ||
702 | |||
703 | static struct uart_driver mpc52xx_uart_driver = { | ||
704 | .owner = THIS_MODULE, | ||
705 | .driver_name = "mpc52xx_psc_uart", | ||
706 | .dev_name = "ttyS", | ||
707 | .devfs_name = "ttyS", | ||
708 | .major = TTY_MAJOR, | ||
709 | .minor = 64, | ||
710 | .nr = MPC52xx_PSC_MAXNUM, | ||
711 | .cons = MPC52xx_PSC_CONSOLE, | ||
712 | }; | ||
713 | |||
714 | |||
715 | /* ======================================================================== */ | ||
716 | /* Platform Driver */ | ||
717 | /* ======================================================================== */ | ||
718 | |||
719 | static int __devinit | ||
720 | mpc52xx_uart_probe(struct device *dev) | ||
721 | { | ||
722 | struct platform_device *pdev = to_platform_device(dev); | ||
723 | struct resource *res = pdev->resource; | ||
724 | |||
725 | struct uart_port *port = NULL; | ||
726 | int i, idx, ret; | ||
727 | |||
728 | /* Check validity & presence */ | ||
729 | idx = pdev->id; | ||
730 | if (idx < 0 || idx >= MPC52xx_PSC_MAXNUM) | ||
731 | return -EINVAL; | ||
732 | |||
733 | if (!mpc52xx_match_psc_function(idx,"uart")) | ||
734 | return -ENODEV; | ||
735 | |||
736 | /* Init the port structure */ | ||
737 | port = &mpc52xx_uart_ports[idx]; | ||
738 | |||
739 | memset(port, 0x00, sizeof(struct uart_port)); | ||
740 | |||
741 | spin_lock_init(&port->lock); | ||
742 | port->uartclk = __res.bi_ipbfreq / 2; /* Look at CTLR doc */ | ||
743 | port->fifosize = 255; /* Should be 512 ! But it can't be */ | ||
744 | /* stored in a unsigned char */ | ||
745 | port->iotype = UPIO_MEM; | ||
746 | port->flags = UPF_BOOT_AUTOCONF | | ||
747 | ( uart_console(port) ? 0 : UPF_IOREMAP ); | ||
748 | port->line = idx; | ||
749 | port->ops = &mpc52xx_uart_ops; | ||
750 | |||
751 | /* Search for IRQ and mapbase */ | ||
752 | for (i=0 ; i<pdev->num_resources ; i++, res++) { | ||
753 | if (res->flags & IORESOURCE_MEM) | ||
754 | port->mapbase = res->start; | ||
755 | else if (res->flags & IORESOURCE_IRQ) | ||
756 | port->irq = res->start; | ||
757 | } | ||
758 | if (!port->irq || !port->mapbase) | ||
759 | return -EINVAL; | ||
760 | |||
761 | /* Add the port to the uart sub-system */ | ||
762 | ret = uart_add_one_port(&mpc52xx_uart_driver, port); | ||
763 | if (!ret) | ||
764 | dev_set_drvdata(dev, (void*)port); | ||
765 | |||
766 | return ret; | ||
767 | } | ||
768 | |||
769 | static int | ||
770 | mpc52xx_uart_remove(struct device *dev) | ||
771 | { | ||
772 | struct uart_port *port = (struct uart_port *) dev_get_drvdata(dev); | ||
773 | |||
774 | dev_set_drvdata(dev, NULL); | ||
775 | |||
776 | if (port) | ||
777 | uart_remove_one_port(&mpc52xx_uart_driver, port); | ||
778 | |||
779 | return 0; | ||
780 | } | ||
781 | |||
782 | #ifdef CONFIG_PM | ||
783 | static int | ||
784 | mpc52xx_uart_suspend(struct device *dev, u32 state, u32 level) | ||
785 | { | ||
786 | struct uart_port *port = (struct uart_port *) dev_get_drvdata(dev); | ||
787 | |||
788 | if (sport && level == SUSPEND_DISABLE) | ||
789 | uart_suspend_port(&mpc52xx_uart_driver, port); | ||
790 | |||
791 | return 0; | ||
792 | } | ||
793 | |||
794 | static int | ||
795 | mpc52xx_uart_resume(struct device *dev, u32 level) | ||
796 | { | ||
797 | struct uart_port *port = (struct uart_port *) dev_get_drvdata(dev); | ||
798 | |||
799 | if (port && level == RESUME_ENABLE) | ||
800 | uart_resume_port(&mpc52xx_uart_driver, port); | ||
801 | |||
802 | return 0; | ||
803 | } | ||
804 | #endif | ||
805 | |||
806 | static struct device_driver mpc52xx_uart_platform_driver = { | ||
807 | .name = "mpc52xx-psc", | ||
808 | .bus = &platform_bus_type, | ||
809 | .probe = mpc52xx_uart_probe, | ||
810 | .remove = mpc52xx_uart_remove, | ||
811 | #ifdef CONFIG_PM | ||
812 | .suspend = mpc52xx_uart_suspend, | ||
813 | .resume = mpc52xx_uart_resume, | ||
814 | #endif | ||
815 | }; | ||
816 | |||
817 | |||
818 | /* ======================================================================== */ | ||
819 | /* Module */ | ||
820 | /* ======================================================================== */ | ||
821 | |||
822 | static int __init | ||
823 | mpc52xx_uart_init(void) | ||
824 | { | ||
825 | int ret; | ||
826 | |||
827 | printk(KERN_INFO "Serial: MPC52xx PSC driver\n"); | ||
828 | |||
829 | ret = uart_register_driver(&mpc52xx_uart_driver); | ||
830 | if (ret == 0) { | ||
831 | ret = driver_register(&mpc52xx_uart_platform_driver); | ||
832 | if (ret) | ||
833 | uart_unregister_driver(&mpc52xx_uart_driver); | ||
834 | } | ||
835 | |||
836 | return ret; | ||
837 | } | ||
838 | |||
839 | static void __exit | ||
840 | mpc52xx_uart_exit(void) | ||
841 | { | ||
842 | driver_unregister(&mpc52xx_uart_platform_driver); | ||
843 | uart_unregister_driver(&mpc52xx_uart_driver); | ||
844 | } | ||
845 | |||
846 | |||
847 | module_init(mpc52xx_uart_init); | ||
848 | module_exit(mpc52xx_uart_exit); | ||
849 | |||
850 | MODULE_AUTHOR("Sylvain Munaut <tnt@246tNt.com>"); | ||
851 | MODULE_DESCRIPTION("Freescale MPC52xx PSC UART"); | ||
852 | MODULE_LICENSE("GPL"); | ||