1 /*
2  * mfd.c: driver for High Speed UART device of Intel Medfield platform
3  *
4  * Refer pxa.c, 8250.c and some other drivers in drivers/serial/
5  *
6  * (C) Copyright 2010 Intel Corporation
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License
10  * as published by the Free Software Foundation; version 2
11  * of the License.
12  */
13 
14 /* Notes:
15  * 1. DMA channel allocation: 0/1 channel are assigned to port 0,
16  *    2/3 chan to port 1, 4/5 chan to port 3. Even number chans
17  *    are used for RX, odd chans for TX
18  *
19  * 2. The RI/DSR/DCD/DTR are not pinned out, DCD & DSR are always
20  *    asserted, only when the HW is reset the DDCD and DDSR will
21  *    be triggered
22  */
23 
24 #include <linux/module.h>
25 #include <linux/init.h>
26 #include <linux/console.h>
27 #include <linux/sysrq.h>
28 #include <linux/slab.h>
29 #include <linux/serial_reg.h>
30 #include <linux/circ_buf.h>
31 #include <linux/delay.h>
32 #include <linux/interrupt.h>
33 #include <linux/tty.h>
34 #include <linux/tty_flip.h>
35 #include <linux/serial_core.h>
36 #include <linux/serial_mfd.h>
37 #include <linux/dma-mapping.h>
38 #include <linux/pci.h>
39 #include <linux/io.h>
40 #include <linux/debugfs.h>
41 
42 #define HSU_DMA_BUF_SIZE	2048
43 
44 #define chan_readl(chan, offset)	readl(chan->reg + offset)
45 #define chan_writel(chan, offset, val)	writel(val, chan->reg + offset)
46 
47 #define mfd_readl(obj, offset)		readl(obj->reg + offset)
48 #define mfd_writel(obj, offset, val)	writel(val, obj->reg + offset)
49 
50 static int hsu_dma_enable;
51 module_param(hsu_dma_enable, int, 0);
52 MODULE_PARM_DESC(hsu_dma_enable, "It is a bitmap to set working mode, if \
53 bit[x] is 1, then port[x] will work in DMA mode, otherwise in PIO mode.");
54 
55 struct hsu_dma_buffer {
56 	u8		*buf;
57 	dma_addr_t	dma_addr;
58 	u32		dma_size;
59 	u32		ofs;
60 };
61 
62 struct hsu_dma_chan {
63 	u32	id;
64 	enum dma_data_direction	dirt;
65 	struct uart_hsu_port	*uport;
66 	void __iomem		*reg;
67 };
68 
69 struct uart_hsu_port {
70 	struct uart_port        port;
71 	unsigned char           ier;
72 	unsigned char           lcr;
73 	unsigned char           mcr;
74 	unsigned int            lsr_break_flag;
75 	char			name[12];
76 	int			index;
77 	struct device		*dev;
78 
79 	struct hsu_dma_chan	*txc;
80 	struct hsu_dma_chan	*rxc;
81 	struct hsu_dma_buffer	txbuf;
82 	struct hsu_dma_buffer	rxbuf;
83 	int			use_dma;	/* flag for DMA/PIO */
84 	int			running;
85 	int			dma_tx_on;
86 };
87 
88 /* Top level data structure of HSU */
89 struct hsu_port {
90 	void __iomem	*reg;
91 	unsigned long	paddr;
92 	unsigned long	iolen;
93 	u32		irq;
94 
95 	struct uart_hsu_port	port[3];
96 	struct hsu_dma_chan	chans[10];
97 
98 	struct dentry *debugfs;
99 };
100 
serial_in(struct uart_hsu_port * up,int offset)101 static inline unsigned int serial_in(struct uart_hsu_port *up, int offset)
102 {
103 	unsigned int val;
104 
105 	if (offset > UART_MSR) {
106 		offset <<= 2;
107 		val = readl(up->port.membase + offset);
108 	} else
109 		val = (unsigned int)readb(up->port.membase + offset);
110 
111 	return val;
112 }
113 
serial_out(struct uart_hsu_port * up,int offset,int value)114 static inline void serial_out(struct uart_hsu_port *up, int offset, int value)
115 {
116 	if (offset > UART_MSR) {
117 		offset <<= 2;
118 		writel(value, up->port.membase + offset);
119 	} else {
120 		unsigned char val = value & 0xff;
121 		writeb(val, up->port.membase + offset);
122 	}
123 }
124 
125 #ifdef CONFIG_DEBUG_FS
126 
127 #define HSU_REGS_BUFSIZE	1024
128 
hsu_show_regs_open(struct inode * inode,struct file * file)129 static int hsu_show_regs_open(struct inode *inode, struct file *file)
130 {
131 	file->private_data = inode->i_private;
132 	return 0;
133 }
134 
port_show_regs(struct file * file,char __user * user_buf,size_t count,loff_t * ppos)135 static ssize_t port_show_regs(struct file *file, char __user *user_buf,
136 				size_t count, loff_t *ppos)
137 {
138 	struct uart_hsu_port *up = file->private_data;
139 	char *buf;
140 	u32 len = 0;
141 	ssize_t ret;
142 
143 	buf = kzalloc(HSU_REGS_BUFSIZE, GFP_KERNEL);
144 	if (!buf)
145 		return 0;
146 
147 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
148 			"MFD HSU port[%d] regs:\n", up->index);
149 
150 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
151 			"=================================\n");
152 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
153 			"IER: \t\t0x%08x\n", serial_in(up, UART_IER));
154 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
155 			"IIR: \t\t0x%08x\n", serial_in(up, UART_IIR));
156 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
157 			"LCR: \t\t0x%08x\n", serial_in(up, UART_LCR));
158 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
159 			"MCR: \t\t0x%08x\n", serial_in(up, UART_MCR));
160 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
161 			"LSR: \t\t0x%08x\n", serial_in(up, UART_LSR));
162 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
163 			"MSR: \t\t0x%08x\n", serial_in(up, UART_MSR));
164 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
165 			"FOR: \t\t0x%08x\n", serial_in(up, UART_FOR));
166 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
167 			"PS: \t\t0x%08x\n", serial_in(up, UART_PS));
168 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
169 			"MUL: \t\t0x%08x\n", serial_in(up, UART_MUL));
170 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
171 			"DIV: \t\t0x%08x\n", serial_in(up, UART_DIV));
172 
173 	if (len > HSU_REGS_BUFSIZE)
174 		len = HSU_REGS_BUFSIZE;
175 
176 	ret =  simple_read_from_buffer(user_buf, count, ppos, buf, len);
177 	kfree(buf);
178 	return ret;
179 }
180 
dma_show_regs(struct file * file,char __user * user_buf,size_t count,loff_t * ppos)181 static ssize_t dma_show_regs(struct file *file, char __user *user_buf,
182 				size_t count, loff_t *ppos)
183 {
184 	struct hsu_dma_chan *chan = file->private_data;
185 	char *buf;
186 	u32 len = 0;
187 	ssize_t ret;
188 
189 	buf = kzalloc(HSU_REGS_BUFSIZE, GFP_KERNEL);
190 	if (!buf)
191 		return 0;
192 
193 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
194 			"MFD HSU DMA channel [%d] regs:\n", chan->id);
195 
196 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
197 			"=================================\n");
198 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
199 			"CR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_CR));
200 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
201 			"DCR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_DCR));
202 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
203 			"BSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_BSR));
204 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
205 			"MOTSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_MOTSR));
206 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
207 			"D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D0SAR));
208 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
209 			"D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D0TSR));
210 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
211 			"D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D1SAR));
212 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
213 			"D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D1TSR));
214 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
215 			"D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D2SAR));
216 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
217 			"D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D2TSR));
218 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
219 			"D0SAR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D3SAR));
220 	len += snprintf(buf + len, HSU_REGS_BUFSIZE - len,
221 			"D0TSR: \t\t0x%08x\n", chan_readl(chan, HSU_CH_D3TSR));
222 
223 	if (len > HSU_REGS_BUFSIZE)
224 		len = HSU_REGS_BUFSIZE;
225 
226 	ret =  simple_read_from_buffer(user_buf, count, ppos, buf, len);
227 	kfree(buf);
228 	return ret;
229 }
230 
231 static const struct file_operations port_regs_ops = {
232 	.owner		= THIS_MODULE,
233 	.open		= hsu_show_regs_open,
234 	.read		= port_show_regs,
235 	.llseek		= default_llseek,
236 };
237 
238 static const struct file_operations dma_regs_ops = {
239 	.owner		= THIS_MODULE,
240 	.open		= hsu_show_regs_open,
241 	.read		= dma_show_regs,
242 	.llseek		= default_llseek,
243 };
244 
hsu_debugfs_init(struct hsu_port * hsu)245 static int hsu_debugfs_init(struct hsu_port *hsu)
246 {
247 	int i;
248 	char name[32];
249 
250 	hsu->debugfs = debugfs_create_dir("hsu", NULL);
251 	if (!hsu->debugfs)
252 		return -ENOMEM;
253 
254 	for (i = 0; i < 3; i++) {
255 		snprintf(name, sizeof(name), "port_%d_regs", i);
256 		debugfs_create_file(name, S_IFREG | S_IRUGO,
257 			hsu->debugfs, (void *)(&hsu->port[i]), &port_regs_ops);
258 	}
259 
260 	for (i = 0; i < 6; i++) {
261 		snprintf(name, sizeof(name), "dma_chan_%d_regs", i);
262 		debugfs_create_file(name, S_IFREG | S_IRUGO,
263 			hsu->debugfs, (void *)&hsu->chans[i], &dma_regs_ops);
264 	}
265 
266 	return 0;
267 }
268 
hsu_debugfs_remove(struct hsu_port * hsu)269 static void hsu_debugfs_remove(struct hsu_port *hsu)
270 {
271 	if (hsu->debugfs)
272 		debugfs_remove_recursive(hsu->debugfs);
273 }
274 
275 #else
hsu_debugfs_init(struct hsu_port * hsu)276 static inline int hsu_debugfs_init(struct hsu_port *hsu)
277 {
278 	return 0;
279 }
280 
hsu_debugfs_remove(struct hsu_port * hsu)281 static inline void hsu_debugfs_remove(struct hsu_port *hsu)
282 {
283 }
284 #endif /* CONFIG_DEBUG_FS */
285 
serial_hsu_enable_ms(struct uart_port * port)286 static void serial_hsu_enable_ms(struct uart_port *port)
287 {
288 	struct uart_hsu_port *up =
289 		container_of(port, struct uart_hsu_port, port);
290 
291 	up->ier |= UART_IER_MSI;
292 	serial_out(up, UART_IER, up->ier);
293 }
294 
hsu_dma_tx(struct uart_hsu_port * up)295 void hsu_dma_tx(struct uart_hsu_port *up)
296 {
297 	struct circ_buf *xmit = &up->port.state->xmit;
298 	struct hsu_dma_buffer *dbuf = &up->txbuf;
299 	int count;
300 
301 	/* test_and_set_bit may be better, but anyway it's in lock protected mode */
302 	if (up->dma_tx_on)
303 		return;
304 
305 	/* Update the circ buf info */
306 	xmit->tail += dbuf->ofs;
307 	xmit->tail &= UART_XMIT_SIZE - 1;
308 
309 	up->port.icount.tx += dbuf->ofs;
310 	dbuf->ofs = 0;
311 
312 	/* Disable the channel */
313 	chan_writel(up->txc, HSU_CH_CR, 0x0);
314 
315 	if (!uart_circ_empty(xmit) && !uart_tx_stopped(&up->port)) {
316 		dma_sync_single_for_device(up->port.dev,
317 					   dbuf->dma_addr,
318 					   dbuf->dma_size,
319 					   DMA_TO_DEVICE);
320 
321 		count = CIRC_CNT_TO_END(xmit->head, xmit->tail, UART_XMIT_SIZE);
322 		dbuf->ofs = count;
323 
324 		/* Reprogram the channel */
325 		chan_writel(up->txc, HSU_CH_D0SAR, dbuf->dma_addr + xmit->tail);
326 		chan_writel(up->txc, HSU_CH_D0TSR, count);
327 
328 		/* Reenable the channel */
329 		chan_writel(up->txc, HSU_CH_DCR, 0x1
330 						 | (0x1 << 8)
331 						 | (0x1 << 16)
332 						 | (0x1 << 24));
333 		up->dma_tx_on = 1;
334 		chan_writel(up->txc, HSU_CH_CR, 0x1);
335 	}
336 
337 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
338 		uart_write_wakeup(&up->port);
339 }
340 
341 /* The buffer is already cache coherent */
hsu_dma_start_rx_chan(struct hsu_dma_chan * rxc,struct hsu_dma_buffer * dbuf)342 void hsu_dma_start_rx_chan(struct hsu_dma_chan *rxc, struct hsu_dma_buffer *dbuf)
343 {
344 	dbuf->ofs = 0;
345 
346 	chan_writel(rxc, HSU_CH_BSR, 32);
347 	chan_writel(rxc, HSU_CH_MOTSR, 4);
348 
349 	chan_writel(rxc, HSU_CH_D0SAR, dbuf->dma_addr);
350 	chan_writel(rxc, HSU_CH_D0TSR, dbuf->dma_size);
351 	chan_writel(rxc, HSU_CH_DCR, 0x1 | (0x1 << 8)
352 					 | (0x1 << 16)
353 					 | (0x1 << 24)	/* timeout bit, see HSU Errata 1 */
354 					 );
355 	chan_writel(rxc, HSU_CH_CR, 0x3);
356 }
357 
358 /* Protected by spin_lock_irqsave(port->lock) */
serial_hsu_start_tx(struct uart_port * port)359 static void serial_hsu_start_tx(struct uart_port *port)
360 {
361 	struct uart_hsu_port *up =
362 		container_of(port, struct uart_hsu_port, port);
363 
364 	if (up->use_dma) {
365 		hsu_dma_tx(up);
366 	} else if (!(up->ier & UART_IER_THRI)) {
367 		up->ier |= UART_IER_THRI;
368 		serial_out(up, UART_IER, up->ier);
369 	}
370 }
371 
serial_hsu_stop_tx(struct uart_port * port)372 static void serial_hsu_stop_tx(struct uart_port *port)
373 {
374 	struct uart_hsu_port *up =
375 		container_of(port, struct uart_hsu_port, port);
376 	struct hsu_dma_chan *txc = up->txc;
377 
378 	if (up->use_dma)
379 		chan_writel(txc, HSU_CH_CR, 0x0);
380 	else if (up->ier & UART_IER_THRI) {
381 		up->ier &= ~UART_IER_THRI;
382 		serial_out(up, UART_IER, up->ier);
383 	}
384 }
385 
386 /* This is always called in spinlock protected mode, so
387  * modify timeout timer is safe here */
hsu_dma_rx(struct uart_hsu_port * up,u32 int_sts)388 void hsu_dma_rx(struct uart_hsu_port *up, u32 int_sts)
389 {
390 	struct hsu_dma_buffer *dbuf = &up->rxbuf;
391 	struct hsu_dma_chan *chan = up->rxc;
392 	struct uart_port *port = &up->port;
393 	struct tty_struct *tty = port->state->port.tty;
394 	int count;
395 
396 	if (!tty)
397 		return;
398 
399 	/*
400 	 * First need to know how many is already transferred,
401 	 * then check if its a timeout DMA irq, and return
402 	 * the trail bytes out, push them up and reenable the
403 	 * channel
404 	 */
405 
406 	/* Timeout IRQ, need wait some time, see Errata 2 */
407 	if (int_sts & 0xf00)
408 		udelay(2);
409 
410 	/* Stop the channel */
411 	chan_writel(chan, HSU_CH_CR, 0x0);
412 
413 	count = chan_readl(chan, HSU_CH_D0SAR) - dbuf->dma_addr;
414 	if (!count) {
415 		/* Restart the channel before we leave */
416 		chan_writel(chan, HSU_CH_CR, 0x3);
417 		return;
418 	}
419 
420 	dma_sync_single_for_cpu(port->dev, dbuf->dma_addr,
421 			dbuf->dma_size, DMA_FROM_DEVICE);
422 
423 	/*
424 	 * Head will only wrap around when we recycle
425 	 * the DMA buffer, and when that happens, we
426 	 * explicitly set tail to 0. So head will
427 	 * always be greater than tail.
428 	 */
429 	tty_insert_flip_string(tty, dbuf->buf, count);
430 	port->icount.rx += count;
431 
432 	dma_sync_single_for_device(up->port.dev, dbuf->dma_addr,
433 			dbuf->dma_size, DMA_FROM_DEVICE);
434 
435 	/* Reprogram the channel */
436 	chan_writel(chan, HSU_CH_D0SAR, dbuf->dma_addr);
437 	chan_writel(chan, HSU_CH_D0TSR, dbuf->dma_size);
438 	chan_writel(chan, HSU_CH_DCR, 0x1
439 					 | (0x1 << 8)
440 					 | (0x1 << 16)
441 					 | (0x1 << 24)	/* timeout bit, see HSU Errata 1 */
442 					 );
443 	tty_flip_buffer_push(tty);
444 
445 	chan_writel(chan, HSU_CH_CR, 0x3);
446 
447 }
448 
serial_hsu_stop_rx(struct uart_port * port)449 static void serial_hsu_stop_rx(struct uart_port *port)
450 {
451 	struct uart_hsu_port *up =
452 		container_of(port, struct uart_hsu_port, port);
453 	struct hsu_dma_chan *chan = up->rxc;
454 
455 	if (up->use_dma)
456 		chan_writel(chan, HSU_CH_CR, 0x2);
457 	else {
458 		up->ier &= ~UART_IER_RLSI;
459 		up->port.read_status_mask &= ~UART_LSR_DR;
460 		serial_out(up, UART_IER, up->ier);
461 	}
462 }
463 
receive_chars(struct uart_hsu_port * up,int * status)464 static inline void receive_chars(struct uart_hsu_port *up, int *status)
465 {
466 	struct tty_struct *tty = up->port.state->port.tty;
467 	unsigned int ch, flag;
468 	unsigned int max_count = 256;
469 
470 	if (!tty)
471 		return;
472 
473 	do {
474 		ch = serial_in(up, UART_RX);
475 		flag = TTY_NORMAL;
476 		up->port.icount.rx++;
477 
478 		if (unlikely(*status & (UART_LSR_BI | UART_LSR_PE |
479 				       UART_LSR_FE | UART_LSR_OE))) {
480 
481 			dev_warn(up->dev, "We really rush into ERR/BI case"
482 				"status = 0x%02x", *status);
483 			/* For statistics only */
484 			if (*status & UART_LSR_BI) {
485 				*status &= ~(UART_LSR_FE | UART_LSR_PE);
486 				up->port.icount.brk++;
487 				/*
488 				 * We do the SysRQ and SAK checking
489 				 * here because otherwise the break
490 				 * may get masked by ignore_status_mask
491 				 * or read_status_mask.
492 				 */
493 				if (uart_handle_break(&up->port))
494 					goto ignore_char;
495 			} else if (*status & UART_LSR_PE)
496 				up->port.icount.parity++;
497 			else if (*status & UART_LSR_FE)
498 				up->port.icount.frame++;
499 			if (*status & UART_LSR_OE)
500 				up->port.icount.overrun++;
501 
502 			/* Mask off conditions which should be ignored. */
503 			*status &= up->port.read_status_mask;
504 
505 #ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE
506 			if (up->port.cons &&
507 				up->port.cons->index == up->port.line) {
508 				/* Recover the break flag from console xmit */
509 				*status |= up->lsr_break_flag;
510 				up->lsr_break_flag = 0;
511 			}
512 #endif
513 			if (*status & UART_LSR_BI) {
514 				flag = TTY_BREAK;
515 			} else if (*status & UART_LSR_PE)
516 				flag = TTY_PARITY;
517 			else if (*status & UART_LSR_FE)
518 				flag = TTY_FRAME;
519 		}
520 
521 		if (uart_handle_sysrq_char(&up->port, ch))
522 			goto ignore_char;
523 
524 		uart_insert_char(&up->port, *status, UART_LSR_OE, ch, flag);
525 	ignore_char:
526 		*status = serial_in(up, UART_LSR);
527 	} while ((*status & UART_LSR_DR) && max_count--);
528 	tty_flip_buffer_push(tty);
529 }
530 
transmit_chars(struct uart_hsu_port * up)531 static void transmit_chars(struct uart_hsu_port *up)
532 {
533 	struct circ_buf *xmit = &up->port.state->xmit;
534 	int count;
535 
536 	if (up->port.x_char) {
537 		serial_out(up, UART_TX, up->port.x_char);
538 		up->port.icount.tx++;
539 		up->port.x_char = 0;
540 		return;
541 	}
542 	if (uart_circ_empty(xmit) || uart_tx_stopped(&up->port)) {
543 		serial_hsu_stop_tx(&up->port);
544 		return;
545 	}
546 
547 	/* The IRQ is for TX FIFO half-empty */
548 	count = up->port.fifosize / 2;
549 
550 	do {
551 		serial_out(up, UART_TX, xmit->buf[xmit->tail]);
552 		xmit->tail = (xmit->tail + 1) & (UART_XMIT_SIZE - 1);
553 
554 		up->port.icount.tx++;
555 		if (uart_circ_empty(xmit))
556 			break;
557 	} while (--count > 0);
558 
559 	if (uart_circ_chars_pending(xmit) < WAKEUP_CHARS)
560 		uart_write_wakeup(&up->port);
561 
562 	if (uart_circ_empty(xmit))
563 		serial_hsu_stop_tx(&up->port);
564 }
565 
check_modem_status(struct uart_hsu_port * up)566 static inline void check_modem_status(struct uart_hsu_port *up)
567 {
568 	int status;
569 
570 	status = serial_in(up, UART_MSR);
571 
572 	if ((status & UART_MSR_ANY_DELTA) == 0)
573 		return;
574 
575 	if (status & UART_MSR_TERI)
576 		up->port.icount.rng++;
577 	if (status & UART_MSR_DDSR)
578 		up->port.icount.dsr++;
579 	/* We may only get DDCD when HW init and reset */
580 	if (status & UART_MSR_DDCD)
581 		uart_handle_dcd_change(&up->port, status & UART_MSR_DCD);
582 	/* Will start/stop_tx accordingly */
583 	if (status & UART_MSR_DCTS)
584 		uart_handle_cts_change(&up->port, status & UART_MSR_CTS);
585 
586 	wake_up_interruptible(&up->port.state->port.delta_msr_wait);
587 }
588 
589 /*
590  * This handles the interrupt from one port.
591  */
port_irq(int irq,void * dev_id)592 static irqreturn_t port_irq(int irq, void *dev_id)
593 {
594 	struct uart_hsu_port *up = dev_id;
595 	unsigned int iir, lsr;
596 	unsigned long flags;
597 
598 	if (unlikely(!up->running))
599 		return IRQ_NONE;
600 
601 	spin_lock_irqsave(&up->port.lock, flags);
602 	if (up->use_dma) {
603 		lsr = serial_in(up, UART_LSR);
604 		if (unlikely(lsr & (UART_LSR_BI | UART_LSR_PE |
605 				       UART_LSR_FE | UART_LSR_OE)))
606 			dev_warn(up->dev,
607 				"Got lsr irq while using DMA, lsr = 0x%2x\n",
608 				lsr);
609 		check_modem_status(up);
610 		spin_unlock_irqrestore(&up->port.lock, flags);
611 		return IRQ_HANDLED;
612 	}
613 
614 	iir = serial_in(up, UART_IIR);
615 	if (iir & UART_IIR_NO_INT) {
616 		spin_unlock_irqrestore(&up->port.lock, flags);
617 		return IRQ_NONE;
618 	}
619 
620 	lsr = serial_in(up, UART_LSR);
621 	if (lsr & UART_LSR_DR)
622 		receive_chars(up, &lsr);
623 	check_modem_status(up);
624 
625 	/* lsr will be renewed during the receive_chars */
626 	if (lsr & UART_LSR_THRE)
627 		transmit_chars(up);
628 
629 	spin_unlock_irqrestore(&up->port.lock, flags);
630 	return IRQ_HANDLED;
631 }
632 
dma_chan_irq(struct hsu_dma_chan * chan)633 static inline void dma_chan_irq(struct hsu_dma_chan *chan)
634 {
635 	struct uart_hsu_port *up = chan->uport;
636 	unsigned long flags;
637 	u32 int_sts;
638 
639 	spin_lock_irqsave(&up->port.lock, flags);
640 
641 	if (!up->use_dma || !up->running)
642 		goto exit;
643 
644 	/*
645 	 * No matter what situation, need read clear the IRQ status
646 	 * There is a bug, see Errata 5, HSD 2900918
647 	 */
648 	int_sts = chan_readl(chan, HSU_CH_SR);
649 
650 	/* Rx channel */
651 	if (chan->dirt == DMA_FROM_DEVICE)
652 		hsu_dma_rx(up, int_sts);
653 
654 	/* Tx channel */
655 	if (chan->dirt == DMA_TO_DEVICE) {
656 		chan_writel(chan, HSU_CH_CR, 0x0);
657 		up->dma_tx_on = 0;
658 		hsu_dma_tx(up);
659 	}
660 
661 exit:
662 	spin_unlock_irqrestore(&up->port.lock, flags);
663 	return;
664 }
665 
dma_irq(int irq,void * dev_id)666 static irqreturn_t dma_irq(int irq, void *dev_id)
667 {
668 	struct hsu_port *hsu = dev_id;
669 	u32 int_sts, i;
670 
671 	int_sts = mfd_readl(hsu, HSU_GBL_DMAISR);
672 
673 	/* Currently we only have 6 channels may be used */
674 	for (i = 0; i < 6; i++) {
675 		if (int_sts & 0x1)
676 			dma_chan_irq(&hsu->chans[i]);
677 		int_sts >>= 1;
678 	}
679 
680 	return IRQ_HANDLED;
681 }
682 
serial_hsu_tx_empty(struct uart_port * port)683 static unsigned int serial_hsu_tx_empty(struct uart_port *port)
684 {
685 	struct uart_hsu_port *up =
686 		container_of(port, struct uart_hsu_port, port);
687 	unsigned long flags;
688 	unsigned int ret;
689 
690 	spin_lock_irqsave(&up->port.lock, flags);
691 	ret = serial_in(up, UART_LSR) & UART_LSR_TEMT ? TIOCSER_TEMT : 0;
692 	spin_unlock_irqrestore(&up->port.lock, flags);
693 
694 	return ret;
695 }
696 
serial_hsu_get_mctrl(struct uart_port * port)697 static unsigned int serial_hsu_get_mctrl(struct uart_port *port)
698 {
699 	struct uart_hsu_port *up =
700 		container_of(port, struct uart_hsu_port, port);
701 	unsigned char status;
702 	unsigned int ret;
703 
704 	status = serial_in(up, UART_MSR);
705 
706 	ret = 0;
707 	if (status & UART_MSR_DCD)
708 		ret |= TIOCM_CAR;
709 	if (status & UART_MSR_RI)
710 		ret |= TIOCM_RNG;
711 	if (status & UART_MSR_DSR)
712 		ret |= TIOCM_DSR;
713 	if (status & UART_MSR_CTS)
714 		ret |= TIOCM_CTS;
715 	return ret;
716 }
717 
serial_hsu_set_mctrl(struct uart_port * port,unsigned int mctrl)718 static void serial_hsu_set_mctrl(struct uart_port *port, unsigned int mctrl)
719 {
720 	struct uart_hsu_port *up =
721 		container_of(port, struct uart_hsu_port, port);
722 	unsigned char mcr = 0;
723 
724 	if (mctrl & TIOCM_RTS)
725 		mcr |= UART_MCR_RTS;
726 	if (mctrl & TIOCM_DTR)
727 		mcr |= UART_MCR_DTR;
728 	if (mctrl & TIOCM_OUT1)
729 		mcr |= UART_MCR_OUT1;
730 	if (mctrl & TIOCM_OUT2)
731 		mcr |= UART_MCR_OUT2;
732 	if (mctrl & TIOCM_LOOP)
733 		mcr |= UART_MCR_LOOP;
734 
735 	mcr |= up->mcr;
736 
737 	serial_out(up, UART_MCR, mcr);
738 }
739 
serial_hsu_break_ctl(struct uart_port * port,int break_state)740 static void serial_hsu_break_ctl(struct uart_port *port, int break_state)
741 {
742 	struct uart_hsu_port *up =
743 		container_of(port, struct uart_hsu_port, port);
744 	unsigned long flags;
745 
746 	spin_lock_irqsave(&up->port.lock, flags);
747 	if (break_state == -1)
748 		up->lcr |= UART_LCR_SBC;
749 	else
750 		up->lcr &= ~UART_LCR_SBC;
751 	serial_out(up, UART_LCR, up->lcr);
752 	spin_unlock_irqrestore(&up->port.lock, flags);
753 }
754 
755 /*
756  * What special to do:
757  * 1. chose the 64B fifo mode
758  * 2. start dma or pio depends on configuration
759  * 3. we only allocate dma memory when needed
760  */
serial_hsu_startup(struct uart_port * port)761 static int serial_hsu_startup(struct uart_port *port)
762 {
763 	struct uart_hsu_port *up =
764 		container_of(port, struct uart_hsu_port, port);
765 	unsigned long flags;
766 
767 	/*
768 	 * Clear the FIFO buffers and disable them.
769 	 * (they will be reenabled in set_termios())
770 	 */
771 	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO);
772 	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
773 			UART_FCR_CLEAR_RCVR | UART_FCR_CLEAR_XMIT);
774 	serial_out(up, UART_FCR, 0);
775 
776 	/* Clear the interrupt registers. */
777 	(void) serial_in(up, UART_LSR);
778 	(void) serial_in(up, UART_RX);
779 	(void) serial_in(up, UART_IIR);
780 	(void) serial_in(up, UART_MSR);
781 
782 	/* Now, initialize the UART, default is 8n1 */
783 	serial_out(up, UART_LCR, UART_LCR_WLEN8);
784 
785 	spin_lock_irqsave(&up->port.lock, flags);
786 
787 	up->port.mctrl |= TIOCM_OUT2;
788 	serial_hsu_set_mctrl(&up->port, up->port.mctrl);
789 
790 	/*
791 	 * Finally, enable interrupts.  Note: Modem status interrupts
792 	 * are set via set_termios(), which will be occurring imminently
793 	 * anyway, so we don't enable them here.
794 	 */
795 	if (!up->use_dma)
796 		up->ier = UART_IER_RLSI | UART_IER_RDI | UART_IER_RTOIE;
797 	else
798 		up->ier = 0;
799 	serial_out(up, UART_IER, up->ier);
800 
801 	spin_unlock_irqrestore(&up->port.lock, flags);
802 
803 	/* DMA init */
804 	if (up->use_dma) {
805 		struct hsu_dma_buffer *dbuf;
806 		struct circ_buf *xmit = &port->state->xmit;
807 
808 		up->dma_tx_on = 0;
809 
810 		/* First allocate the RX buffer */
811 		dbuf = &up->rxbuf;
812 		dbuf->buf = kzalloc(HSU_DMA_BUF_SIZE, GFP_KERNEL);
813 		if (!dbuf->buf) {
814 			up->use_dma = 0;
815 			goto exit;
816 		}
817 		dbuf->dma_addr = dma_map_single(port->dev,
818 						dbuf->buf,
819 						HSU_DMA_BUF_SIZE,
820 						DMA_FROM_DEVICE);
821 		dbuf->dma_size = HSU_DMA_BUF_SIZE;
822 
823 		/* Start the RX channel right now */
824 		hsu_dma_start_rx_chan(up->rxc, dbuf);
825 
826 		/* Next init the TX DMA */
827 		dbuf = &up->txbuf;
828 		dbuf->buf = xmit->buf;
829 		dbuf->dma_addr = dma_map_single(port->dev,
830 					       dbuf->buf,
831 					       UART_XMIT_SIZE,
832 					       DMA_TO_DEVICE);
833 		dbuf->dma_size = UART_XMIT_SIZE;
834 
835 		/* This should not be changed all around */
836 		chan_writel(up->txc, HSU_CH_BSR, 32);
837 		chan_writel(up->txc, HSU_CH_MOTSR, 4);
838 		dbuf->ofs = 0;
839 	}
840 
841 exit:
842 	 /* And clear the interrupt registers again for luck. */
843 	(void) serial_in(up, UART_LSR);
844 	(void) serial_in(up, UART_RX);
845 	(void) serial_in(up, UART_IIR);
846 	(void) serial_in(up, UART_MSR);
847 
848 	up->running = 1;
849 	return 0;
850 }
851 
serial_hsu_shutdown(struct uart_port * port)852 static void serial_hsu_shutdown(struct uart_port *port)
853 {
854 	struct uart_hsu_port *up =
855 		container_of(port, struct uart_hsu_port, port);
856 	unsigned long flags;
857 
858 	/* Disable interrupts from this port */
859 	up->ier = 0;
860 	serial_out(up, UART_IER, 0);
861 	up->running = 0;
862 
863 	spin_lock_irqsave(&up->port.lock, flags);
864 	up->port.mctrl &= ~TIOCM_OUT2;
865 	serial_hsu_set_mctrl(&up->port, up->port.mctrl);
866 	spin_unlock_irqrestore(&up->port.lock, flags);
867 
868 	/* Disable break condition and FIFOs */
869 	serial_out(up, UART_LCR, serial_in(up, UART_LCR) & ~UART_LCR_SBC);
870 	serial_out(up, UART_FCR, UART_FCR_ENABLE_FIFO |
871 				  UART_FCR_CLEAR_RCVR |
872 				  UART_FCR_CLEAR_XMIT);
873 	serial_out(up, UART_FCR, 0);
874 }
875 
876 static void
serial_hsu_set_termios(struct uart_port * port,struct ktermios * termios,struct ktermios * old)877 serial_hsu_set_termios(struct uart_port *port, struct ktermios *termios,
878 		       struct ktermios *old)
879 {
880 	struct uart_hsu_port *up =
881 			container_of(port, struct uart_hsu_port, port);
882 	struct tty_struct *tty = port->state->port.tty;
883 	unsigned char cval, fcr = 0;
884 	unsigned long flags;
885 	unsigned int baud, quot;
886 	u32 ps, mul;
887 
888 	switch (termios->c_cflag & CSIZE) {
889 	case CS5:
890 		cval = UART_LCR_WLEN5;
891 		break;
892 	case CS6:
893 		cval = UART_LCR_WLEN6;
894 		break;
895 	case CS7:
896 		cval = UART_LCR_WLEN7;
897 		break;
898 	default:
899 	case CS8:
900 		cval = UART_LCR_WLEN8;
901 		break;
902 	}
903 
904 	/* CMSPAR isn't supported by this driver */
905 	if (tty)
906 		tty->termios->c_cflag &= ~CMSPAR;
907 
908 	if (termios->c_cflag & CSTOPB)
909 		cval |= UART_LCR_STOP;
910 	if (termios->c_cflag & PARENB)
911 		cval |= UART_LCR_PARITY;
912 	if (!(termios->c_cflag & PARODD))
913 		cval |= UART_LCR_EPAR;
914 
915 	/*
916 	 * The base clk is 50Mhz, and the baud rate come from:
917 	 *	baud = 50M * MUL / (DIV * PS * DLAB)
918 	 *
919 	 * For those basic low baud rate we can get the direct
920 	 * scalar from 2746800, like 115200 = 2746800/24. For those
921 	 * higher baud rate, we handle them case by case, mainly by
922 	 * adjusting the MUL/PS registers, and DIV register is kept
923 	 * as default value 0x3d09 to make things simple
924 	 */
925 	baud = uart_get_baud_rate(port, termios, old, 0, 4000000);
926 
927 	quot = 1;
928 	ps = 0x10;
929 	mul = 0x3600;
930 	switch (baud) {
931 	case 3500000:
932 		mul = 0x3345;
933 		ps = 0xC;
934 		break;
935 	case 1843200:
936 		mul = 0x2400;
937 		break;
938 	case 3000000:
939 	case 2500000:
940 	case 2000000:
941 	case 1500000:
942 	case 1000000:
943 	case 500000:
944 		/* mul/ps/quot = 0x9C4/0x10/0x1 will make a 500000 bps */
945 		mul = baud / 500000 * 0x9C4;
946 		break;
947 	default:
948 		/* Use uart_get_divisor to get quot for other baud rates */
949 		quot = 0;
950 	}
951 
952 	if (!quot)
953 		quot = uart_get_divisor(port, baud);
954 
955 	if ((up->port.uartclk / quot) < (2400 * 16))
956 		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_HSU_64_1B;
957 	else if ((up->port.uartclk / quot) < (230400 * 16))
958 		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_HSU_64_16B;
959 	else
960 		fcr = UART_FCR_ENABLE_FIFO | UART_FCR_HSU_64_32B;
961 
962 	fcr |= UART_FCR_HSU_64B_FIFO;
963 
964 	/*
965 	 * Ok, we're now changing the port state.  Do it with
966 	 * interrupts disabled.
967 	 */
968 	spin_lock_irqsave(&up->port.lock, flags);
969 
970 	/* Update the per-port timeout */
971 	uart_update_timeout(port, termios->c_cflag, baud);
972 
973 	up->port.read_status_mask = UART_LSR_OE | UART_LSR_THRE | UART_LSR_DR;
974 	if (termios->c_iflag & INPCK)
975 		up->port.read_status_mask |= UART_LSR_FE | UART_LSR_PE;
976 	if (termios->c_iflag & (BRKINT | PARMRK))
977 		up->port.read_status_mask |= UART_LSR_BI;
978 
979 	/* Characters to ignore */
980 	up->port.ignore_status_mask = 0;
981 	if (termios->c_iflag & IGNPAR)
982 		up->port.ignore_status_mask |= UART_LSR_PE | UART_LSR_FE;
983 	if (termios->c_iflag & IGNBRK) {
984 		up->port.ignore_status_mask |= UART_LSR_BI;
985 		/*
986 		 * If we're ignoring parity and break indicators,
987 		 * ignore overruns too (for real raw support).
988 		 */
989 		if (termios->c_iflag & IGNPAR)
990 			up->port.ignore_status_mask |= UART_LSR_OE;
991 	}
992 
993 	/* Ignore all characters if CREAD is not set */
994 	if ((termios->c_cflag & CREAD) == 0)
995 		up->port.ignore_status_mask |= UART_LSR_DR;
996 
997 	/*
998 	 * CTS flow control flag and modem status interrupts, disable
999 	 * MSI by default
1000 	 */
1001 	up->ier &= ~UART_IER_MSI;
1002 	if (UART_ENABLE_MS(&up->port, termios->c_cflag))
1003 		up->ier |= UART_IER_MSI;
1004 
1005 	serial_out(up, UART_IER, up->ier);
1006 
1007 	if (termios->c_cflag & CRTSCTS)
1008 		up->mcr |= UART_MCR_AFE | UART_MCR_RTS;
1009 	else
1010 		up->mcr &= ~UART_MCR_AFE;
1011 
1012 	serial_out(up, UART_LCR, cval | UART_LCR_DLAB);	/* set DLAB */
1013 	serial_out(up, UART_DLL, quot & 0xff);		/* LS of divisor */
1014 	serial_out(up, UART_DLM, quot >> 8);		/* MS of divisor */
1015 	serial_out(up, UART_LCR, cval);			/* reset DLAB */
1016 	serial_out(up, UART_MUL, mul);			/* set MUL */
1017 	serial_out(up, UART_PS, ps);			/* set PS */
1018 	up->lcr = cval;					/* Save LCR */
1019 	serial_hsu_set_mctrl(&up->port, up->port.mctrl);
1020 	serial_out(up, UART_FCR, fcr);
1021 	spin_unlock_irqrestore(&up->port.lock, flags);
1022 }
1023 
1024 static void
serial_hsu_pm(struct uart_port * port,unsigned int state,unsigned int oldstate)1025 serial_hsu_pm(struct uart_port *port, unsigned int state,
1026 	      unsigned int oldstate)
1027 {
1028 }
1029 
serial_hsu_release_port(struct uart_port * port)1030 static void serial_hsu_release_port(struct uart_port *port)
1031 {
1032 }
1033 
serial_hsu_request_port(struct uart_port * port)1034 static int serial_hsu_request_port(struct uart_port *port)
1035 {
1036 	return 0;
1037 }
1038 
serial_hsu_config_port(struct uart_port * port,int flags)1039 static void serial_hsu_config_port(struct uart_port *port, int flags)
1040 {
1041 	struct uart_hsu_port *up =
1042 		container_of(port, struct uart_hsu_port, port);
1043 	up->port.type = PORT_MFD;
1044 }
1045 
1046 static int
serial_hsu_verify_port(struct uart_port * port,struct serial_struct * ser)1047 serial_hsu_verify_port(struct uart_port *port, struct serial_struct *ser)
1048 {
1049 	/* We don't want the core code to modify any port params */
1050 	return -EINVAL;
1051 }
1052 
1053 static const char *
serial_hsu_type(struct uart_port * port)1054 serial_hsu_type(struct uart_port *port)
1055 {
1056 	struct uart_hsu_port *up =
1057 		container_of(port, struct uart_hsu_port, port);
1058 	return up->name;
1059 }
1060 
1061 /* Mainly for uart console use */
1062 static struct uart_hsu_port *serial_hsu_ports[3];
1063 static struct uart_driver serial_hsu_reg;
1064 
1065 #ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE
1066 
1067 #define BOTH_EMPTY (UART_LSR_TEMT | UART_LSR_THRE)
1068 
1069 /* Wait for transmitter & holding register to empty */
wait_for_xmitr(struct uart_hsu_port * up)1070 static inline void wait_for_xmitr(struct uart_hsu_port *up)
1071 {
1072 	unsigned int status, tmout = 1000;
1073 
1074 	/* Wait up to 1ms for the character to be sent. */
1075 	do {
1076 		status = serial_in(up, UART_LSR);
1077 
1078 		if (status & UART_LSR_BI)
1079 			up->lsr_break_flag = UART_LSR_BI;
1080 
1081 		if (--tmout == 0)
1082 			break;
1083 		udelay(1);
1084 	} while (!(status & BOTH_EMPTY));
1085 
1086 	/* Wait up to 1s for flow control if necessary */
1087 	if (up->port.flags & UPF_CONS_FLOW) {
1088 		tmout = 1000000;
1089 		while (--tmout &&
1090 		       ((serial_in(up, UART_MSR) & UART_MSR_CTS) == 0))
1091 			udelay(1);
1092 	}
1093 }
1094 
serial_hsu_console_putchar(struct uart_port * port,int ch)1095 static void serial_hsu_console_putchar(struct uart_port *port, int ch)
1096 {
1097 	struct uart_hsu_port *up =
1098 		container_of(port, struct uart_hsu_port, port);
1099 
1100 	wait_for_xmitr(up);
1101 	serial_out(up, UART_TX, ch);
1102 }
1103 
1104 /*
1105  * Print a string to the serial port trying not to disturb
1106  * any possible real use of the port...
1107  *
1108  *	The console_lock must be held when we get here.
1109  */
1110 static void
serial_hsu_console_write(struct console * co,const char * s,unsigned int count)1111 serial_hsu_console_write(struct console *co, const char *s, unsigned int count)
1112 {
1113 	struct uart_hsu_port *up = serial_hsu_ports[co->index];
1114 	unsigned long flags;
1115 	unsigned int ier;
1116 	int locked = 1;
1117 
1118 	local_irq_save(flags);
1119 	if (up->port.sysrq)
1120 		locked = 0;
1121 	else if (oops_in_progress) {
1122 		locked = spin_trylock(&up->port.lock);
1123 	} else
1124 		spin_lock(&up->port.lock);
1125 
1126 	/* First save the IER then disable the interrupts */
1127 	ier = serial_in(up, UART_IER);
1128 	serial_out(up, UART_IER, 0);
1129 
1130 	uart_console_write(&up->port, s, count, serial_hsu_console_putchar);
1131 
1132 	/*
1133 	 * Finally, wait for transmitter to become empty
1134 	 * and restore the IER
1135 	 */
1136 	wait_for_xmitr(up);
1137 	serial_out(up, UART_IER, ier);
1138 
1139 	if (locked)
1140 		spin_unlock(&up->port.lock);
1141 	local_irq_restore(flags);
1142 }
1143 
1144 static struct console serial_hsu_console;
1145 
1146 static int __init
serial_hsu_console_setup(struct console * co,char * options)1147 serial_hsu_console_setup(struct console *co, char *options)
1148 {
1149 	struct uart_hsu_port *up;
1150 	int baud = 115200;
1151 	int bits = 8;
1152 	int parity = 'n';
1153 	int flow = 'n';
1154 	int ret;
1155 
1156 	if (co->index == -1 || co->index >= serial_hsu_reg.nr)
1157 		co->index = 0;
1158 	up = serial_hsu_ports[co->index];
1159 	if (!up)
1160 		return -ENODEV;
1161 
1162 	if (options)
1163 		uart_parse_options(options, &baud, &parity, &bits, &flow);
1164 
1165 	ret = uart_set_options(&up->port, co, baud, parity, bits, flow);
1166 
1167 	return ret;
1168 }
1169 
1170 static struct console serial_hsu_console = {
1171 	.name		= "ttyMFD",
1172 	.write		= serial_hsu_console_write,
1173 	.device		= uart_console_device,
1174 	.setup		= serial_hsu_console_setup,
1175 	.flags		= CON_PRINTBUFFER,
1176 	.index		= 2,
1177 	.data		= &serial_hsu_reg,
1178 };
1179 #endif
1180 
1181 struct uart_ops serial_hsu_pops = {
1182 	.tx_empty	= serial_hsu_tx_empty,
1183 	.set_mctrl	= serial_hsu_set_mctrl,
1184 	.get_mctrl	= serial_hsu_get_mctrl,
1185 	.stop_tx	= serial_hsu_stop_tx,
1186 	.start_tx	= serial_hsu_start_tx,
1187 	.stop_rx	= serial_hsu_stop_rx,
1188 	.enable_ms	= serial_hsu_enable_ms,
1189 	.break_ctl	= serial_hsu_break_ctl,
1190 	.startup	= serial_hsu_startup,
1191 	.shutdown	= serial_hsu_shutdown,
1192 	.set_termios	= serial_hsu_set_termios,
1193 	.pm		= serial_hsu_pm,
1194 	.type		= serial_hsu_type,
1195 	.release_port	= serial_hsu_release_port,
1196 	.request_port	= serial_hsu_request_port,
1197 	.config_port	= serial_hsu_config_port,
1198 	.verify_port	= serial_hsu_verify_port,
1199 };
1200 
1201 static struct uart_driver serial_hsu_reg = {
1202 	.owner		= THIS_MODULE,
1203 	.driver_name	= "MFD serial",
1204 	.dev_name	= "ttyMFD",
1205 	.major		= TTY_MAJOR,
1206 	.minor		= 128,
1207 	.nr		= 3,
1208 };
1209 
1210 #ifdef CONFIG_PM
serial_hsu_suspend(struct pci_dev * pdev,pm_message_t state)1211 static int serial_hsu_suspend(struct pci_dev *pdev, pm_message_t state)
1212 {
1213 	void *priv = pci_get_drvdata(pdev);
1214 	struct uart_hsu_port *up;
1215 
1216 	/* Make sure this is not the internal dma controller */
1217 	if (priv && (pdev->device != 0x081E)) {
1218 		up = priv;
1219 		uart_suspend_port(&serial_hsu_reg, &up->port);
1220 	}
1221 
1222 	pci_save_state(pdev);
1223 	pci_set_power_state(pdev, pci_choose_state(pdev, state));
1224         return 0;
1225 }
1226 
serial_hsu_resume(struct pci_dev * pdev)1227 static int serial_hsu_resume(struct pci_dev *pdev)
1228 {
1229 	void *priv = pci_get_drvdata(pdev);
1230 	struct uart_hsu_port *up;
1231 	int ret;
1232 
1233 	pci_set_power_state(pdev, PCI_D0);
1234 	pci_restore_state(pdev);
1235 
1236 	ret = pci_enable_device(pdev);
1237 	if (ret)
1238 		dev_warn(&pdev->dev,
1239 			"HSU: can't re-enable device, try to continue\n");
1240 
1241 	if (priv && (pdev->device != 0x081E)) {
1242 		up = priv;
1243 		uart_resume_port(&serial_hsu_reg, &up->port);
1244 	}
1245 	return 0;
1246 }
1247 #else
1248 #define serial_hsu_suspend	NULL
1249 #define serial_hsu_resume	NULL
1250 #endif
1251 
1252 /* temp global pointer before we settle down on using one or four PCI dev */
1253 static struct hsu_port *phsu;
1254 
serial_hsu_probe(struct pci_dev * pdev,const struct pci_device_id * ent)1255 static int serial_hsu_probe(struct pci_dev *pdev,
1256 				const struct pci_device_id *ent)
1257 {
1258 	struct uart_hsu_port *uport;
1259 	int index, ret;
1260 
1261 	printk(KERN_INFO "HSU: found PCI Serial controller(ID: %04x:%04x)\n",
1262 		pdev->vendor, pdev->device);
1263 
1264 	switch (pdev->device) {
1265 	case 0x081B:
1266 		index = 0;
1267 		break;
1268 	case 0x081C:
1269 		index = 1;
1270 		break;
1271 	case 0x081D:
1272 		index = 2;
1273 		break;
1274 	case 0x081E:
1275 		/* internal DMA controller */
1276 		index = 3;
1277 		break;
1278 	default:
1279 		dev_err(&pdev->dev, "HSU: out of index!");
1280 		return -ENODEV;
1281 	}
1282 
1283 	ret = pci_enable_device(pdev);
1284 	if (ret)
1285 		return ret;
1286 
1287 	if (index == 3) {
1288 		/* DMA controller */
1289 		ret = request_irq(pdev->irq, dma_irq, 0, "hsu_dma", phsu);
1290 		if (ret) {
1291 			dev_err(&pdev->dev, "can not get IRQ\n");
1292 			goto err_disable;
1293 		}
1294 		pci_set_drvdata(pdev, phsu);
1295 	} else {
1296 		/* UART port 0~2 */
1297 		uport = &phsu->port[index];
1298 		uport->port.irq = pdev->irq;
1299 		uport->port.dev = &pdev->dev;
1300 		uport->dev = &pdev->dev;
1301 
1302 		ret = request_irq(pdev->irq, port_irq, 0, uport->name, uport);
1303 		if (ret) {
1304 			dev_err(&pdev->dev, "can not get IRQ\n");
1305 			goto err_disable;
1306 		}
1307 		uart_add_one_port(&serial_hsu_reg, &uport->port);
1308 
1309 #ifdef CONFIG_SERIAL_MFD_HSU_CONSOLE
1310 		if (index == 2) {
1311 			register_console(&serial_hsu_console);
1312 			uport->port.cons = &serial_hsu_console;
1313 		}
1314 #endif
1315 		pci_set_drvdata(pdev, uport);
1316 	}
1317 
1318 	return 0;
1319 
1320 err_disable:
1321 	pci_disable_device(pdev);
1322 	return ret;
1323 }
1324 
hsu_global_init(void)1325 static void hsu_global_init(void)
1326 {
1327 	struct hsu_port *hsu;
1328 	struct uart_hsu_port *uport;
1329 	struct hsu_dma_chan *dchan;
1330 	int i, ret;
1331 
1332 	hsu = kzalloc(sizeof(struct hsu_port), GFP_KERNEL);
1333 	if (!hsu)
1334 		return;
1335 
1336 	/* Get basic io resource and map it */
1337 	hsu->paddr = 0xffa28000;
1338 	hsu->iolen = 0x1000;
1339 
1340 	if (!(request_mem_region(hsu->paddr, hsu->iolen, "HSU global")))
1341 		pr_warning("HSU: error in request mem region\n");
1342 
1343 	hsu->reg = ioremap_nocache((unsigned long)hsu->paddr, hsu->iolen);
1344 	if (!hsu->reg) {
1345 		pr_err("HSU: error in ioremap\n");
1346 		ret = -ENOMEM;
1347 		goto err_free_region;
1348 	}
1349 
1350 	/* Initialise the 3 UART ports */
1351 	uport = hsu->port;
1352 	for (i = 0; i < 3; i++) {
1353 		uport->port.type = PORT_MFD;
1354 		uport->port.iotype = UPIO_MEM;
1355 		uport->port.mapbase = (resource_size_t)hsu->paddr
1356 					+ HSU_PORT_REG_OFFSET
1357 					+ i * HSU_PORT_REG_LENGTH;
1358 		uport->port.membase = hsu->reg + HSU_PORT_REG_OFFSET
1359 					+ i * HSU_PORT_REG_LENGTH;
1360 
1361 		sprintf(uport->name, "hsu_port%d", i);
1362 		uport->port.fifosize = 64;
1363 		uport->port.ops = &serial_hsu_pops;
1364 		uport->port.line = i;
1365 		uport->port.flags = UPF_IOREMAP;
1366 		/* set the scalable maxim support rate to 2746800 bps */
1367 		uport->port.uartclk = 115200 * 24 * 16;
1368 
1369 		uport->running = 0;
1370 		uport->txc = &hsu->chans[i * 2];
1371 		uport->rxc = &hsu->chans[i * 2 + 1];
1372 
1373 		serial_hsu_ports[i] = uport;
1374 		uport->index = i;
1375 
1376 		if (hsu_dma_enable & (1<<i))
1377 			uport->use_dma = 1;
1378 		else
1379 			uport->use_dma = 0;
1380 
1381 		uport++;
1382 	}
1383 
1384 	/* Initialise 6 dma channels */
1385 	dchan = hsu->chans;
1386 	for (i = 0; i < 6; i++) {
1387 		dchan->id = i;
1388 		dchan->dirt = (i & 0x1) ? DMA_FROM_DEVICE : DMA_TO_DEVICE;
1389 		dchan->uport = &hsu->port[i/2];
1390 		dchan->reg = hsu->reg + HSU_DMA_CHANS_REG_OFFSET +
1391 				i * HSU_DMA_CHANS_REG_LENGTH;
1392 
1393 		dchan++;
1394 	}
1395 
1396 	phsu = hsu;
1397 	hsu_debugfs_init(hsu);
1398 	return;
1399 
1400 err_free_region:
1401 	release_mem_region(hsu->paddr, hsu->iolen);
1402 	kfree(hsu);
1403 	return;
1404 }
1405 
serial_hsu_remove(struct pci_dev * pdev)1406 static void serial_hsu_remove(struct pci_dev *pdev)
1407 {
1408 	void *priv = pci_get_drvdata(pdev);
1409 	struct uart_hsu_port *up;
1410 
1411 	if (!priv)
1412 		return;
1413 
1414 	/* For port 0/1/2, priv is the address of uart_hsu_port */
1415 	if (pdev->device != 0x081E) {
1416 		up = priv;
1417 		uart_remove_one_port(&serial_hsu_reg, &up->port);
1418 	}
1419 
1420 	pci_set_drvdata(pdev, NULL);
1421 	free_irq(pdev->irq, priv);
1422 	pci_disable_device(pdev);
1423 }
1424 
1425 /* First 3 are UART ports, and the 4th is the DMA */
1426 static const struct pci_device_id pci_ids[] __devinitdata = {
1427 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081B) },
1428 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081C) },
1429 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081D) },
1430 	{ PCI_DEVICE(PCI_VENDOR_ID_INTEL, 0x081E) },
1431 	{},
1432 };
1433 
1434 static struct pci_driver hsu_pci_driver = {
1435 	.name =		"HSU serial",
1436 	.id_table =	pci_ids,
1437 	.probe =	serial_hsu_probe,
1438 	.remove =	__devexit_p(serial_hsu_remove),
1439 	.suspend =	serial_hsu_suspend,
1440 	.resume	=	serial_hsu_resume,
1441 };
1442 
hsu_pci_init(void)1443 static int __init hsu_pci_init(void)
1444 {
1445 	int ret;
1446 
1447 	hsu_global_init();
1448 
1449 	ret = uart_register_driver(&serial_hsu_reg);
1450 	if (ret)
1451 		return ret;
1452 
1453 	return pci_register_driver(&hsu_pci_driver);
1454 }
1455 
hsu_pci_exit(void)1456 static void __exit hsu_pci_exit(void)
1457 {
1458 	pci_unregister_driver(&hsu_pci_driver);
1459 	uart_unregister_driver(&serial_hsu_reg);
1460 
1461 	hsu_debugfs_remove(phsu);
1462 
1463 	kfree(phsu);
1464 }
1465 
1466 module_init(hsu_pci_init);
1467 module_exit(hsu_pci_exit);
1468 
1469 MODULE_LICENSE("GPL v2");
1470 MODULE_ALIAS("platform:medfield-hsu");
1471