xref: /openbmc/linux/drivers/i2c/busses/i2c-qup.c (revision 726bd223)
1 /*
2  * Copyright (c) 2009-2013, The Linux Foundation. All rights reserved.
3  * Copyright (c) 2014, Sony Mobile Communications AB.
4  *
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License version 2 and
8  * only version 2 as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  */
16 
17 #include <linux/acpi.h>
18 #include <linux/atomic.h>
19 #include <linux/clk.h>
20 #include <linux/delay.h>
21 #include <linux/dmaengine.h>
22 #include <linux/dmapool.h>
23 #include <linux/dma-mapping.h>
24 #include <linux/err.h>
25 #include <linux/i2c.h>
26 #include <linux/interrupt.h>
27 #include <linux/io.h>
28 #include <linux/module.h>
29 #include <linux/of.h>
30 #include <linux/platform_device.h>
31 #include <linux/pm_runtime.h>
32 #include <linux/scatterlist.h>
33 
34 /* QUP Registers */
35 #define QUP_CONFIG		0x000
36 #define QUP_STATE		0x004
37 #define QUP_IO_MODE		0x008
38 #define QUP_SW_RESET		0x00c
39 #define QUP_OPERATIONAL		0x018
40 #define QUP_ERROR_FLAGS		0x01c
41 #define QUP_ERROR_FLAGS_EN	0x020
42 #define QUP_OPERATIONAL_MASK	0x028
43 #define QUP_HW_VERSION		0x030
44 #define QUP_MX_OUTPUT_CNT	0x100
45 #define QUP_OUT_FIFO_BASE	0x110
46 #define QUP_MX_WRITE_CNT	0x150
47 #define QUP_MX_INPUT_CNT	0x200
48 #define QUP_MX_READ_CNT		0x208
49 #define QUP_IN_FIFO_BASE	0x218
50 #define QUP_I2C_CLK_CTL		0x400
51 #define QUP_I2C_STATUS		0x404
52 #define QUP_I2C_MASTER_GEN	0x408
53 
54 /* QUP States and reset values */
55 #define QUP_RESET_STATE		0
56 #define QUP_RUN_STATE		1
57 #define QUP_PAUSE_STATE		3
58 #define QUP_STATE_MASK		3
59 
60 #define QUP_STATE_VALID		BIT(2)
61 #define QUP_I2C_MAST_GEN	BIT(4)
62 #define QUP_I2C_FLUSH		BIT(6)
63 
64 #define QUP_OPERATIONAL_RESET	0x000ff0
65 #define QUP_I2C_STATUS_RESET	0xfffffc
66 
67 /* QUP OPERATIONAL FLAGS */
68 #define QUP_I2C_NACK_FLAG	BIT(3)
69 #define QUP_OUT_NOT_EMPTY	BIT(4)
70 #define QUP_IN_NOT_EMPTY	BIT(5)
71 #define QUP_OUT_FULL		BIT(6)
72 #define QUP_OUT_SVC_FLAG	BIT(8)
73 #define QUP_IN_SVC_FLAG		BIT(9)
74 #define QUP_MX_OUTPUT_DONE	BIT(10)
75 #define QUP_MX_INPUT_DONE	BIT(11)
76 
77 /* I2C mini core related values */
78 #define QUP_CLOCK_AUTO_GATE	BIT(13)
79 #define I2C_MINI_CORE		(2 << 8)
80 #define I2C_N_VAL		15
81 #define I2C_N_VAL_V2		7
82 
83 /* Most significant word offset in FIFO port */
84 #define QUP_MSW_SHIFT		(I2C_N_VAL + 1)
85 
86 /* Packing/Unpacking words in FIFOs, and IO modes */
87 #define QUP_OUTPUT_BLK_MODE	(1 << 10)
88 #define QUP_OUTPUT_BAM_MODE	(3 << 10)
89 #define QUP_INPUT_BLK_MODE	(1 << 12)
90 #define QUP_INPUT_BAM_MODE	(3 << 12)
91 #define QUP_BAM_MODE		(QUP_OUTPUT_BAM_MODE | QUP_INPUT_BAM_MODE)
92 #define QUP_UNPACK_EN		BIT(14)
93 #define QUP_PACK_EN		BIT(15)
94 
95 #define QUP_REPACK_EN		(QUP_UNPACK_EN | QUP_PACK_EN)
96 #define QUP_V2_TAGS_EN		1
97 
98 #define QUP_OUTPUT_BLOCK_SIZE(x)(((x) >> 0) & 0x03)
99 #define QUP_OUTPUT_FIFO_SIZE(x)	(((x) >> 2) & 0x07)
100 #define QUP_INPUT_BLOCK_SIZE(x)	(((x) >> 5) & 0x03)
101 #define QUP_INPUT_FIFO_SIZE(x)	(((x) >> 7) & 0x07)
102 
103 /* QUP tags */
104 #define QUP_TAG_START		(1 << 8)
105 #define QUP_TAG_DATA		(2 << 8)
106 #define QUP_TAG_STOP		(3 << 8)
107 #define QUP_TAG_REC		(4 << 8)
108 #define QUP_BAM_INPUT_EOT		0x93
109 #define QUP_BAM_FLUSH_STOP		0x96
110 
111 /* QUP v2 tags */
112 #define QUP_TAG_V2_START               0x81
113 #define QUP_TAG_V2_DATAWR              0x82
114 #define QUP_TAG_V2_DATAWR_STOP         0x83
115 #define QUP_TAG_V2_DATARD              0x85
116 #define QUP_TAG_V2_DATARD_STOP         0x87
117 
118 /* Status, Error flags */
119 #define I2C_STATUS_WR_BUFFER_FULL	BIT(0)
120 #define I2C_STATUS_BUS_ACTIVE		BIT(8)
121 #define I2C_STATUS_ERROR_MASK		0x38000fc
122 #define QUP_STATUS_ERROR_FLAGS		0x7c
123 
124 #define QUP_READ_LIMIT			256
125 #define SET_BIT				0x1
126 #define RESET_BIT			0x0
127 #define ONE_BYTE			0x1
128 #define QUP_I2C_MX_CONFIG_DURING_RUN   BIT(31)
129 
130 #define MX_TX_RX_LEN			SZ_64K
131 #define MX_BLOCKS			(MX_TX_RX_LEN / QUP_READ_LIMIT)
132 
133 /* Max timeout in ms for 32k bytes */
134 #define TOUT_MAX			300
135 
136 /* Default values. Use these if FW query fails */
137 #define DEFAULT_CLK_FREQ 100000
138 #define DEFAULT_SRC_CLK 20000000
139 
140 struct qup_i2c_block {
141 	int	count;
142 	int	pos;
143 	int	tx_tag_len;
144 	int	rx_tag_len;
145 	int	data_len;
146 	u8	tags[6];
147 };
148 
149 struct qup_i2c_tag {
150 	u8 *start;
151 	dma_addr_t addr;
152 };
153 
154 struct qup_i2c_bam {
155 	struct	qup_i2c_tag tag;
156 	struct	dma_chan *dma;
157 	struct	scatterlist *sg;
158 };
159 
160 struct qup_i2c_dev {
161 	struct device		*dev;
162 	void __iomem		*base;
163 	int			irq;
164 	struct clk		*clk;
165 	struct clk		*pclk;
166 	struct i2c_adapter	adap;
167 
168 	int			clk_ctl;
169 	int			out_fifo_sz;
170 	int			in_fifo_sz;
171 	int			out_blk_sz;
172 	int			in_blk_sz;
173 
174 	unsigned long		one_byte_t;
175 	struct qup_i2c_block	blk;
176 
177 	struct i2c_msg		*msg;
178 	/* Current posion in user message buffer */
179 	int			pos;
180 	/* I2C protocol errors */
181 	u32			bus_err;
182 	/* QUP core errors */
183 	u32			qup_err;
184 
185 	/* To check if this is the last msg */
186 	bool			is_last;
187 
188 	/* To configure when bus is in run state */
189 	int			config_run;
190 
191 	/* dma parameters */
192 	bool			is_dma;
193 	struct			dma_pool *dpool;
194 	struct			qup_i2c_tag start_tag;
195 	struct			qup_i2c_bam brx;
196 	struct			qup_i2c_bam btx;
197 
198 	struct completion	xfer;
199 };
200 
201 static irqreturn_t qup_i2c_interrupt(int irq, void *dev)
202 {
203 	struct qup_i2c_dev *qup = dev;
204 	u32 bus_err;
205 	u32 qup_err;
206 	u32 opflags;
207 
208 	bus_err = readl(qup->base + QUP_I2C_STATUS);
209 	qup_err = readl(qup->base + QUP_ERROR_FLAGS);
210 	opflags = readl(qup->base + QUP_OPERATIONAL);
211 
212 	if (!qup->msg) {
213 		/* Clear Error interrupt */
214 		writel(QUP_RESET_STATE, qup->base + QUP_STATE);
215 		return IRQ_HANDLED;
216 	}
217 
218 	bus_err &= I2C_STATUS_ERROR_MASK;
219 	qup_err &= QUP_STATUS_ERROR_FLAGS;
220 
221 	/* Clear the error bits in QUP_ERROR_FLAGS */
222 	if (qup_err)
223 		writel(qup_err, qup->base + QUP_ERROR_FLAGS);
224 
225 	/* Clear the error bits in QUP_I2C_STATUS */
226 	if (bus_err)
227 		writel(bus_err, qup->base + QUP_I2C_STATUS);
228 
229 	/* Reset the QUP State in case of error */
230 	if (qup_err || bus_err) {
231 		writel(QUP_RESET_STATE, qup->base + QUP_STATE);
232 		goto done;
233 	}
234 
235 	if (opflags & QUP_IN_SVC_FLAG)
236 		writel(QUP_IN_SVC_FLAG, qup->base + QUP_OPERATIONAL);
237 
238 	if (opflags & QUP_OUT_SVC_FLAG)
239 		writel(QUP_OUT_SVC_FLAG, qup->base + QUP_OPERATIONAL);
240 
241 done:
242 	qup->qup_err = qup_err;
243 	qup->bus_err = bus_err;
244 	complete(&qup->xfer);
245 	return IRQ_HANDLED;
246 }
247 
248 static int qup_i2c_poll_state_mask(struct qup_i2c_dev *qup,
249 				   u32 req_state, u32 req_mask)
250 {
251 	int retries = 1;
252 	u32 state;
253 
254 	/*
255 	 * State transition takes 3 AHB clocks cycles + 3 I2C master clock
256 	 * cycles. So retry once after a 1uS delay.
257 	 */
258 	do {
259 		state = readl(qup->base + QUP_STATE);
260 
261 		if (state & QUP_STATE_VALID &&
262 		    (state & req_mask) == req_state)
263 			return 0;
264 
265 		udelay(1);
266 	} while (retries--);
267 
268 	return -ETIMEDOUT;
269 }
270 
271 static int qup_i2c_poll_state(struct qup_i2c_dev *qup, u32 req_state)
272 {
273 	return qup_i2c_poll_state_mask(qup, req_state, QUP_STATE_MASK);
274 }
275 
276 static void qup_i2c_flush(struct qup_i2c_dev *qup)
277 {
278 	u32 val = readl(qup->base + QUP_STATE);
279 
280 	val |= QUP_I2C_FLUSH;
281 	writel(val, qup->base + QUP_STATE);
282 }
283 
284 static int qup_i2c_poll_state_valid(struct qup_i2c_dev *qup)
285 {
286 	return qup_i2c_poll_state_mask(qup, 0, 0);
287 }
288 
289 static int qup_i2c_poll_state_i2c_master(struct qup_i2c_dev *qup)
290 {
291 	return qup_i2c_poll_state_mask(qup, QUP_I2C_MAST_GEN, QUP_I2C_MAST_GEN);
292 }
293 
294 static int qup_i2c_change_state(struct qup_i2c_dev *qup, u32 state)
295 {
296 	if (qup_i2c_poll_state_valid(qup) != 0)
297 		return -EIO;
298 
299 	writel(state, qup->base + QUP_STATE);
300 
301 	if (qup_i2c_poll_state(qup, state) != 0)
302 		return -EIO;
303 	return 0;
304 }
305 
306 /**
307  * qup_i2c_wait_ready - wait for a give number of bytes in tx/rx path
308  * @qup: The qup_i2c_dev device
309  * @op: The bit/event to wait on
310  * @val: value of the bit to wait on, 0 or 1
311  * @len: The length the bytes to be transferred
312  */
313 static int qup_i2c_wait_ready(struct qup_i2c_dev *qup, int op, bool val,
314 			      int len)
315 {
316 	unsigned long timeout;
317 	u32 opflags;
318 	u32 status;
319 	u32 shift = __ffs(op);
320 	int ret = 0;
321 
322 	len *= qup->one_byte_t;
323 	/* timeout after a wait of twice the max time */
324 	timeout = jiffies + len * 4;
325 
326 	for (;;) {
327 		opflags = readl(qup->base + QUP_OPERATIONAL);
328 		status = readl(qup->base + QUP_I2C_STATUS);
329 
330 		if (((opflags & op) >> shift) == val) {
331 			if ((op == QUP_OUT_NOT_EMPTY) && qup->is_last) {
332 				if (!(status & I2C_STATUS_BUS_ACTIVE)) {
333 					ret = 0;
334 					goto done;
335 				}
336 			} else {
337 				ret = 0;
338 				goto done;
339 			}
340 		}
341 
342 		if (time_after(jiffies, timeout)) {
343 			ret = -ETIMEDOUT;
344 			goto done;
345 		}
346 		usleep_range(len, len * 2);
347 	}
348 
349 done:
350 	if (qup->bus_err || qup->qup_err)
351 		ret =  (qup->bus_err & QUP_I2C_NACK_FLAG) ? -ENXIO : -EIO;
352 
353 	return ret;
354 }
355 
356 static void qup_i2c_set_write_mode_v2(struct qup_i2c_dev *qup,
357 				      struct i2c_msg *msg)
358 {
359 	/* Number of entries to shift out, including the tags */
360 	int total = msg->len + qup->blk.tx_tag_len;
361 
362 	total |= qup->config_run;
363 
364 	if (total < qup->out_fifo_sz) {
365 		/* FIFO mode */
366 		writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE);
367 		writel(total, qup->base + QUP_MX_WRITE_CNT);
368 	} else {
369 		/* BLOCK mode (transfer data on chunks) */
370 		writel(QUP_OUTPUT_BLK_MODE | QUP_REPACK_EN,
371 		       qup->base + QUP_IO_MODE);
372 		writel(total, qup->base + QUP_MX_OUTPUT_CNT);
373 	}
374 }
375 
376 static void qup_i2c_set_write_mode(struct qup_i2c_dev *qup, struct i2c_msg *msg)
377 {
378 	/* Number of entries to shift out, including the start */
379 	int total = msg->len + 1;
380 
381 	if (total < qup->out_fifo_sz) {
382 		/* FIFO mode */
383 		writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE);
384 		writel(total, qup->base + QUP_MX_WRITE_CNT);
385 	} else {
386 		/* BLOCK mode (transfer data on chunks) */
387 		writel(QUP_OUTPUT_BLK_MODE | QUP_REPACK_EN,
388 		       qup->base + QUP_IO_MODE);
389 		writel(total, qup->base + QUP_MX_OUTPUT_CNT);
390 	}
391 }
392 
393 static int check_for_fifo_space(struct qup_i2c_dev *qup)
394 {
395 	int ret;
396 
397 	ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
398 	if (ret)
399 		goto out;
400 
401 	ret = qup_i2c_wait_ready(qup, QUP_OUT_FULL,
402 				 RESET_BIT, 4 * ONE_BYTE);
403 	if (ret) {
404 		/* Fifo is full. Drain out the fifo */
405 		ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
406 		if (ret)
407 			goto out;
408 
409 		ret = qup_i2c_wait_ready(qup, QUP_OUT_NOT_EMPTY,
410 					 RESET_BIT, 256 * ONE_BYTE);
411 		if (ret) {
412 			dev_err(qup->dev, "timeout for fifo out full");
413 			goto out;
414 		}
415 
416 		ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
417 		if (ret)
418 			goto out;
419 	}
420 
421 out:
422 	return ret;
423 }
424 
425 static int qup_i2c_issue_write(struct qup_i2c_dev *qup, struct i2c_msg *msg)
426 {
427 	u32 addr = msg->addr << 1;
428 	u32 qup_tag;
429 	int idx;
430 	u32 val;
431 	int ret = 0;
432 
433 	if (qup->pos == 0) {
434 		val = QUP_TAG_START | addr;
435 		idx = 1;
436 	} else {
437 		val = 0;
438 		idx = 0;
439 	}
440 
441 	while (qup->pos < msg->len) {
442 		/* Check that there's space in the FIFO for our pair */
443 		ret = check_for_fifo_space(qup);
444 		if (ret)
445 			return ret;
446 
447 		if (qup->pos == msg->len - 1)
448 			qup_tag = QUP_TAG_STOP;
449 		else
450 			qup_tag = QUP_TAG_DATA;
451 
452 		if (idx & 1)
453 			val |= (qup_tag | msg->buf[qup->pos]) << QUP_MSW_SHIFT;
454 		else
455 			val = qup_tag | msg->buf[qup->pos];
456 
457 		/* Write out the pair and the last odd value */
458 		if (idx & 1 || qup->pos == msg->len - 1)
459 			writel(val, qup->base + QUP_OUT_FIFO_BASE);
460 
461 		qup->pos++;
462 		idx++;
463 	}
464 
465 	ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
466 
467 	return ret;
468 }
469 
470 static void qup_i2c_set_blk_data(struct qup_i2c_dev *qup,
471 				 struct i2c_msg *msg)
472 {
473 	memset(&qup->blk, 0, sizeof(qup->blk));
474 
475 	qup->blk.data_len = msg->len;
476 	qup->blk.count = (msg->len + QUP_READ_LIMIT - 1) / QUP_READ_LIMIT;
477 
478 	/* 4 bytes for first block and 2 writes for rest */
479 	qup->blk.tx_tag_len = 4 + (qup->blk.count - 1) * 2;
480 
481 	/* There are 2 tag bytes that are read in to fifo for every block */
482 	if (msg->flags & I2C_M_RD)
483 		qup->blk.rx_tag_len = qup->blk.count * 2;
484 }
485 
486 static int qup_i2c_send_data(struct qup_i2c_dev *qup, int tlen, u8 *tbuf,
487 			     int dlen, u8 *dbuf)
488 {
489 	u32 val = 0, idx = 0, pos = 0, i = 0, t;
490 	int  len = tlen + dlen;
491 	u8 *buf = tbuf;
492 	int ret = 0;
493 
494 	while (len > 0) {
495 		ret = check_for_fifo_space(qup);
496 		if (ret)
497 			return ret;
498 
499 		t = (len >= 4) ? 4 : len;
500 
501 		while (idx < t) {
502 			if (!i && (pos >= tlen)) {
503 				buf = dbuf;
504 				pos = 0;
505 				i = 1;
506 			}
507 			val |= buf[pos++] << (idx++ * 8);
508 		}
509 
510 		writel(val, qup->base + QUP_OUT_FIFO_BASE);
511 		idx  = 0;
512 		val = 0;
513 		len -= 4;
514 	}
515 
516 	ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
517 
518 	return ret;
519 }
520 
521 static int qup_i2c_get_data_len(struct qup_i2c_dev *qup)
522 {
523 	int data_len;
524 
525 	if (qup->blk.data_len > QUP_READ_LIMIT)
526 		data_len = QUP_READ_LIMIT;
527 	else
528 		data_len = qup->blk.data_len;
529 
530 	return data_len;
531 }
532 
533 static bool qup_i2c_check_msg_len(struct i2c_msg *msg)
534 {
535 	return ((msg->flags & I2C_M_RD) && (msg->flags & I2C_M_RECV_LEN));
536 }
537 
538 static int qup_i2c_set_tags_smb(u16 addr, u8 *tags, struct qup_i2c_dev *qup,
539 			struct i2c_msg *msg)
540 {
541 	int len = 0;
542 
543 	if (msg->len > 1) {
544 		tags[len++] = QUP_TAG_V2_DATARD_STOP;
545 		tags[len++] = qup_i2c_get_data_len(qup) - 1;
546 	} else {
547 		tags[len++] = QUP_TAG_V2_START;
548 		tags[len++] = addr & 0xff;
549 
550 		if (msg->flags & I2C_M_TEN)
551 			tags[len++] = addr >> 8;
552 
553 		tags[len++] = QUP_TAG_V2_DATARD;
554 		/* Read 1 byte indicating the length of the SMBus message */
555 		tags[len++] = 1;
556 	}
557 	return len;
558 }
559 
560 static int qup_i2c_set_tags(u8 *tags, struct qup_i2c_dev *qup,
561 			    struct i2c_msg *msg,  int is_dma)
562 {
563 	u16 addr = i2c_8bit_addr_from_msg(msg);
564 	int len = 0;
565 	int data_len;
566 
567 	int last = (qup->blk.pos == (qup->blk.count - 1)) && (qup->is_last);
568 
569 	/* Handle tags for SMBus block read */
570 	if (qup_i2c_check_msg_len(msg))
571 		return qup_i2c_set_tags_smb(addr, tags, qup, msg);
572 
573 	if (qup->blk.pos == 0) {
574 		tags[len++] = QUP_TAG_V2_START;
575 		tags[len++] = addr & 0xff;
576 
577 		if (msg->flags & I2C_M_TEN)
578 			tags[len++] = addr >> 8;
579 	}
580 
581 	/* Send _STOP commands for the last block */
582 	if (last) {
583 		if (msg->flags & I2C_M_RD)
584 			tags[len++] = QUP_TAG_V2_DATARD_STOP;
585 		else
586 			tags[len++] = QUP_TAG_V2_DATAWR_STOP;
587 	} else {
588 		if (msg->flags & I2C_M_RD)
589 			tags[len++] = QUP_TAG_V2_DATARD;
590 		else
591 			tags[len++] = QUP_TAG_V2_DATAWR;
592 	}
593 
594 	data_len = qup_i2c_get_data_len(qup);
595 
596 	/* 0 implies 256 bytes */
597 	if (data_len == QUP_READ_LIMIT)
598 		tags[len++] = 0;
599 	else
600 		tags[len++] = data_len;
601 
602 	if ((msg->flags & I2C_M_RD) && last && is_dma) {
603 		tags[len++] = QUP_BAM_INPUT_EOT;
604 		tags[len++] = QUP_BAM_FLUSH_STOP;
605 	}
606 
607 	return len;
608 }
609 
610 static int qup_i2c_issue_xfer_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg)
611 {
612 	int data_len = 0, tag_len, index;
613 	int ret;
614 
615 	tag_len = qup_i2c_set_tags(qup->blk.tags, qup, msg, 0);
616 	index = msg->len - qup->blk.data_len;
617 
618 	/* only tags are written for read */
619 	if (!(msg->flags & I2C_M_RD))
620 		data_len = qup_i2c_get_data_len(qup);
621 
622 	ret = qup_i2c_send_data(qup, tag_len, qup->blk.tags,
623 				data_len, &msg->buf[index]);
624 	qup->blk.data_len -= data_len;
625 
626 	return ret;
627 }
628 
629 static void qup_i2c_bam_cb(void *data)
630 {
631 	struct qup_i2c_dev *qup = data;
632 
633 	complete(&qup->xfer);
634 }
635 
636 static int qup_sg_set_buf(struct scatterlist *sg, void *buf,
637 			  unsigned int buflen, struct qup_i2c_dev *qup,
638 			  int dir)
639 {
640 	int ret;
641 
642 	sg_set_buf(sg, buf, buflen);
643 	ret = dma_map_sg(qup->dev, sg, 1, dir);
644 	if (!ret)
645 		return -EINVAL;
646 
647 	return 0;
648 }
649 
650 static void qup_i2c_rel_dma(struct qup_i2c_dev *qup)
651 {
652 	if (qup->btx.dma)
653 		dma_release_channel(qup->btx.dma);
654 	if (qup->brx.dma)
655 		dma_release_channel(qup->brx.dma);
656 	qup->btx.dma = NULL;
657 	qup->brx.dma = NULL;
658 }
659 
660 static int qup_i2c_req_dma(struct qup_i2c_dev *qup)
661 {
662 	int err;
663 
664 	if (!qup->btx.dma) {
665 		qup->btx.dma = dma_request_slave_channel_reason(qup->dev, "tx");
666 		if (IS_ERR(qup->btx.dma)) {
667 			err = PTR_ERR(qup->btx.dma);
668 			qup->btx.dma = NULL;
669 			dev_err(qup->dev, "\n tx channel not available");
670 			return err;
671 		}
672 	}
673 
674 	if (!qup->brx.dma) {
675 		qup->brx.dma = dma_request_slave_channel_reason(qup->dev, "rx");
676 		if (IS_ERR(qup->brx.dma)) {
677 			dev_err(qup->dev, "\n rx channel not available");
678 			err = PTR_ERR(qup->brx.dma);
679 			qup->brx.dma = NULL;
680 			qup_i2c_rel_dma(qup);
681 			return err;
682 		}
683 	}
684 	return 0;
685 }
686 
687 static int qup_i2c_bam_do_xfer(struct qup_i2c_dev *qup, struct i2c_msg *msg,
688 			       int num)
689 {
690 	struct dma_async_tx_descriptor *txd, *rxd = NULL;
691 	int ret = 0, idx = 0, limit = QUP_READ_LIMIT;
692 	dma_cookie_t cookie_rx, cookie_tx;
693 	u32 rx_nents = 0, tx_nents = 0, len, blocks, rem;
694 	u32 i, tlen, tx_len, tx_buf = 0, rx_buf = 0, off = 0;
695 	u8 *tags;
696 
697 	while (idx < num) {
698 		tx_len = 0, len = 0, i = 0;
699 
700 		qup->is_last = (idx == (num - 1));
701 
702 		qup_i2c_set_blk_data(qup, msg);
703 
704 		blocks = qup->blk.count;
705 		rem = msg->len - (blocks - 1) * limit;
706 
707 		if (msg->flags & I2C_M_RD) {
708 			rx_nents += (blocks * 2) + 1;
709 			tx_nents += 1;
710 
711 			while (qup->blk.pos < blocks) {
712 				tlen = (i == (blocks - 1)) ? rem : limit;
713 				tags = &qup->start_tag.start[off + len];
714 				len += qup_i2c_set_tags(tags, qup, msg, 1);
715 				qup->blk.data_len -= tlen;
716 
717 				/* scratch buf to read the start and len tags */
718 				ret = qup_sg_set_buf(&qup->brx.sg[rx_buf++],
719 						     &qup->brx.tag.start[0],
720 						     2, qup, DMA_FROM_DEVICE);
721 
722 				if (ret)
723 					return ret;
724 
725 				ret = qup_sg_set_buf(&qup->brx.sg[rx_buf++],
726 						     &msg->buf[limit * i],
727 						     tlen, qup,
728 						     DMA_FROM_DEVICE);
729 				if (ret)
730 					return ret;
731 
732 				i++;
733 				qup->blk.pos = i;
734 			}
735 			ret = qup_sg_set_buf(&qup->btx.sg[tx_buf++],
736 					     &qup->start_tag.start[off],
737 					     len, qup, DMA_TO_DEVICE);
738 			if (ret)
739 				return ret;
740 
741 			off += len;
742 			/* scratch buf to read the BAM EOT and FLUSH tags */
743 			ret = qup_sg_set_buf(&qup->brx.sg[rx_buf++],
744 					     &qup->brx.tag.start[0],
745 					     2, qup, DMA_FROM_DEVICE);
746 			if (ret)
747 				return ret;
748 		} else {
749 			tx_nents += (blocks * 2);
750 
751 			while (qup->blk.pos < blocks) {
752 				tlen = (i == (blocks - 1)) ? rem : limit;
753 				tags = &qup->start_tag.start[off + tx_len];
754 				len = qup_i2c_set_tags(tags, qup, msg, 1);
755 				qup->blk.data_len -= tlen;
756 
757 				ret = qup_sg_set_buf(&qup->btx.sg[tx_buf++],
758 						     tags, len,
759 						     qup, DMA_TO_DEVICE);
760 				if (ret)
761 					return ret;
762 
763 				tx_len += len;
764 				ret = qup_sg_set_buf(&qup->btx.sg[tx_buf++],
765 						     &msg->buf[limit * i],
766 						     tlen, qup, DMA_TO_DEVICE);
767 				if (ret)
768 					return ret;
769 				i++;
770 				qup->blk.pos = i;
771 			}
772 			off += tx_len;
773 
774 			if (idx == (num - 1)) {
775 				len = 1;
776 				if (rx_nents) {
777 					qup->btx.tag.start[0] =
778 							QUP_BAM_INPUT_EOT;
779 					len++;
780 				}
781 				qup->btx.tag.start[len - 1] =
782 							QUP_BAM_FLUSH_STOP;
783 				ret = qup_sg_set_buf(&qup->btx.sg[tx_buf++],
784 						     &qup->btx.tag.start[0],
785 						     len, qup, DMA_TO_DEVICE);
786 				if (ret)
787 					return ret;
788 				tx_nents += 1;
789 			}
790 		}
791 		idx++;
792 		msg++;
793 	}
794 
795 	txd = dmaengine_prep_slave_sg(qup->btx.dma, qup->btx.sg, tx_nents,
796 				      DMA_MEM_TO_DEV,
797 				      DMA_PREP_INTERRUPT | DMA_PREP_FENCE);
798 	if (!txd) {
799 		dev_err(qup->dev, "failed to get tx desc\n");
800 		ret = -EINVAL;
801 		goto desc_err;
802 	}
803 
804 	if (!rx_nents) {
805 		txd->callback = qup_i2c_bam_cb;
806 		txd->callback_param = qup;
807 	}
808 
809 	cookie_tx = dmaengine_submit(txd);
810 	if (dma_submit_error(cookie_tx)) {
811 		ret = -EINVAL;
812 		goto desc_err;
813 	}
814 
815 	dma_async_issue_pending(qup->btx.dma);
816 
817 	if (rx_nents) {
818 		rxd = dmaengine_prep_slave_sg(qup->brx.dma, qup->brx.sg,
819 					      rx_nents, DMA_DEV_TO_MEM,
820 					      DMA_PREP_INTERRUPT);
821 		if (!rxd) {
822 			dev_err(qup->dev, "failed to get rx desc\n");
823 			ret = -EINVAL;
824 
825 			/* abort TX descriptors */
826 			dmaengine_terminate_all(qup->btx.dma);
827 			goto desc_err;
828 		}
829 
830 		rxd->callback = qup_i2c_bam_cb;
831 		rxd->callback_param = qup;
832 		cookie_rx = dmaengine_submit(rxd);
833 		if (dma_submit_error(cookie_rx)) {
834 			ret = -EINVAL;
835 			goto desc_err;
836 		}
837 
838 		dma_async_issue_pending(qup->brx.dma);
839 	}
840 
841 	if (!wait_for_completion_timeout(&qup->xfer, TOUT_MAX * HZ)) {
842 		dev_err(qup->dev, "normal trans timed out\n");
843 		ret = -ETIMEDOUT;
844 	}
845 
846 	if (ret || qup->bus_err || qup->qup_err) {
847 		if (qup_i2c_change_state(qup, QUP_RUN_STATE)) {
848 			dev_err(qup->dev, "change to run state timed out");
849 			goto desc_err;
850 		}
851 
852 		if (rx_nents)
853 			writel(QUP_BAM_INPUT_EOT,
854 			       qup->base + QUP_OUT_FIFO_BASE);
855 
856 		writel(QUP_BAM_FLUSH_STOP, qup->base + QUP_OUT_FIFO_BASE);
857 
858 		qup_i2c_flush(qup);
859 
860 		/* wait for remaining interrupts to occur */
861 		if (!wait_for_completion_timeout(&qup->xfer, HZ))
862 			dev_err(qup->dev, "flush timed out\n");
863 
864 		qup_i2c_rel_dma(qup);
865 
866 		ret =  (qup->bus_err & QUP_I2C_NACK_FLAG) ? -ENXIO : -EIO;
867 	}
868 
869 desc_err:
870 	dma_unmap_sg(qup->dev, qup->btx.sg, tx_nents, DMA_TO_DEVICE);
871 
872 	if (rx_nents)
873 		dma_unmap_sg(qup->dev, qup->brx.sg, rx_nents,
874 			     DMA_FROM_DEVICE);
875 
876 	return ret;
877 }
878 
879 static int qup_i2c_bam_xfer(struct i2c_adapter *adap, struct i2c_msg *msg,
880 			    int num)
881 {
882 	struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
883 	int ret = 0;
884 
885 	enable_irq(qup->irq);
886 	ret = qup_i2c_req_dma(qup);
887 
888 	if (ret)
889 		goto out;
890 
891 	writel(0, qup->base + QUP_MX_INPUT_CNT);
892 	writel(0, qup->base + QUP_MX_OUTPUT_CNT);
893 
894 	/* set BAM mode */
895 	writel(QUP_REPACK_EN | QUP_BAM_MODE, qup->base + QUP_IO_MODE);
896 
897 	/* mask fifo irqs */
898 	writel((0x3 << 8), qup->base + QUP_OPERATIONAL_MASK);
899 
900 	/* set RUN STATE */
901 	ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
902 	if (ret)
903 		goto out;
904 
905 	writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
906 
907 	qup->msg = msg;
908 	ret = qup_i2c_bam_do_xfer(qup, qup->msg, num);
909 out:
910 	disable_irq(qup->irq);
911 
912 	qup->msg = NULL;
913 	return ret;
914 }
915 
916 static int qup_i2c_wait_for_complete(struct qup_i2c_dev *qup,
917 				     struct i2c_msg *msg)
918 {
919 	unsigned long left;
920 	int ret = 0;
921 
922 	left = wait_for_completion_timeout(&qup->xfer, HZ);
923 	if (!left) {
924 		writel(1, qup->base + QUP_SW_RESET);
925 		ret = -ETIMEDOUT;
926 	}
927 
928 	if (qup->bus_err || qup->qup_err)
929 		ret =  (qup->bus_err & QUP_I2C_NACK_FLAG) ? -ENXIO : -EIO;
930 
931 	return ret;
932 }
933 
934 static int qup_i2c_write_one_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg)
935 {
936 	int ret = 0;
937 
938 	qup->msg = msg;
939 	qup->pos = 0;
940 	enable_irq(qup->irq);
941 	qup_i2c_set_blk_data(qup, msg);
942 	qup_i2c_set_write_mode_v2(qup, msg);
943 
944 	ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
945 	if (ret)
946 		goto err;
947 
948 	writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
949 
950 	do {
951 		ret = qup_i2c_issue_xfer_v2(qup, msg);
952 		if (ret)
953 			goto err;
954 
955 		ret = qup_i2c_wait_for_complete(qup, msg);
956 		if (ret)
957 			goto err;
958 
959 		qup->blk.pos++;
960 	} while (qup->blk.pos < qup->blk.count);
961 
962 	ret = qup_i2c_wait_ready(qup, QUP_OUT_NOT_EMPTY, RESET_BIT, ONE_BYTE);
963 
964 err:
965 	disable_irq(qup->irq);
966 	qup->msg = NULL;
967 
968 	return ret;
969 }
970 
971 static int qup_i2c_write_one(struct qup_i2c_dev *qup, struct i2c_msg *msg)
972 {
973 	int ret;
974 
975 	qup->msg = msg;
976 	qup->pos = 0;
977 
978 	enable_irq(qup->irq);
979 
980 	qup_i2c_set_write_mode(qup, msg);
981 
982 	ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
983 	if (ret)
984 		goto err;
985 
986 	writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
987 
988 	do {
989 		ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
990 		if (ret)
991 			goto err;
992 
993 		ret = qup_i2c_issue_write(qup, msg);
994 		if (ret)
995 			goto err;
996 
997 		ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
998 		if (ret)
999 			goto err;
1000 
1001 		ret = qup_i2c_wait_for_complete(qup, msg);
1002 		if (ret)
1003 			goto err;
1004 	} while (qup->pos < msg->len);
1005 
1006 	/* Wait for the outstanding data in the fifo to drain */
1007 	ret = qup_i2c_wait_ready(qup, QUP_OUT_NOT_EMPTY, RESET_BIT, ONE_BYTE);
1008 err:
1009 	disable_irq(qup->irq);
1010 	qup->msg = NULL;
1011 
1012 	return ret;
1013 }
1014 
1015 static void qup_i2c_set_read_mode(struct qup_i2c_dev *qup, int len)
1016 {
1017 	if (len < qup->in_fifo_sz) {
1018 		/* FIFO mode */
1019 		writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE);
1020 		writel(len, qup->base + QUP_MX_READ_CNT);
1021 	} else {
1022 		/* BLOCK mode (transfer data on chunks) */
1023 		writel(QUP_INPUT_BLK_MODE | QUP_REPACK_EN,
1024 		       qup->base + QUP_IO_MODE);
1025 		writel(len, qup->base + QUP_MX_INPUT_CNT);
1026 	}
1027 }
1028 
1029 static void qup_i2c_set_read_mode_v2(struct qup_i2c_dev *qup, int len)
1030 {
1031 	int tx_len = qup->blk.tx_tag_len;
1032 
1033 	len += qup->blk.rx_tag_len;
1034 	len |= qup->config_run;
1035 	tx_len |= qup->config_run;
1036 
1037 	if (len < qup->in_fifo_sz) {
1038 		/* FIFO mode */
1039 		writel(QUP_REPACK_EN, qup->base + QUP_IO_MODE);
1040 		writel(tx_len, qup->base + QUP_MX_WRITE_CNT);
1041 		writel(len, qup->base + QUP_MX_READ_CNT);
1042 	} else {
1043 		/* BLOCK mode (transfer data on chunks) */
1044 		writel(QUP_INPUT_BLK_MODE | QUP_REPACK_EN,
1045 		       qup->base + QUP_IO_MODE);
1046 		writel(tx_len, qup->base + QUP_MX_OUTPUT_CNT);
1047 		writel(len, qup->base + QUP_MX_INPUT_CNT);
1048 	}
1049 }
1050 
1051 static void qup_i2c_issue_read(struct qup_i2c_dev *qup, struct i2c_msg *msg)
1052 {
1053 	u32 addr, len, val;
1054 
1055 	addr = i2c_8bit_addr_from_msg(msg);
1056 
1057 	/* 0 is used to specify a length 256 (QUP_READ_LIMIT) */
1058 	len = (msg->len == QUP_READ_LIMIT) ? 0 : msg->len;
1059 
1060 	val = ((QUP_TAG_REC | len) << QUP_MSW_SHIFT) | QUP_TAG_START | addr;
1061 	writel(val, qup->base + QUP_OUT_FIFO_BASE);
1062 }
1063 
1064 
1065 static int qup_i2c_read_fifo(struct qup_i2c_dev *qup, struct i2c_msg *msg)
1066 {
1067 	u32 val = 0;
1068 	int idx;
1069 	int ret = 0;
1070 
1071 	for (idx = 0; qup->pos < msg->len; idx++) {
1072 		if ((idx & 1) == 0) {
1073 			/* Check that FIFO have data */
1074 			ret = qup_i2c_wait_ready(qup, QUP_IN_NOT_EMPTY,
1075 						 SET_BIT, 4 * ONE_BYTE);
1076 			if (ret)
1077 				return ret;
1078 
1079 			/* Reading 2 words at time */
1080 			val = readl(qup->base + QUP_IN_FIFO_BASE);
1081 
1082 			msg->buf[qup->pos++] = val & 0xFF;
1083 		} else {
1084 			msg->buf[qup->pos++] = val >> QUP_MSW_SHIFT;
1085 		}
1086 	}
1087 
1088 	return ret;
1089 }
1090 
1091 static int qup_i2c_read_fifo_v2(struct qup_i2c_dev *qup,
1092 				struct i2c_msg *msg)
1093 {
1094 	u32 val;
1095 	int idx, pos = 0, ret = 0, total, msg_offset = 0;
1096 
1097 	/*
1098 	 * If the message length is already read in
1099 	 * the first byte of the buffer, account for
1100 	 * that by setting the offset
1101 	 */
1102 	if (qup_i2c_check_msg_len(msg) && (msg->len > 1))
1103 		msg_offset = 1;
1104 	total = qup_i2c_get_data_len(qup);
1105 	total -= msg_offset;
1106 
1107 	/* 2 extra bytes for read tags */
1108 	while (pos < (total + 2)) {
1109 		/* Check that FIFO have data */
1110 		ret = qup_i2c_wait_ready(qup, QUP_IN_NOT_EMPTY,
1111 					 SET_BIT, 4 * ONE_BYTE);
1112 		if (ret) {
1113 			dev_err(qup->dev, "timeout for fifo not empty");
1114 			return ret;
1115 		}
1116 		val = readl(qup->base + QUP_IN_FIFO_BASE);
1117 
1118 		for (idx = 0; idx < 4; idx++, val >>= 8, pos++) {
1119 			/* first 2 bytes are tag bytes */
1120 			if (pos < 2)
1121 				continue;
1122 
1123 			if (pos >= (total + 2))
1124 				goto out;
1125 			msg->buf[qup->pos + msg_offset] = val & 0xff;
1126 			qup->pos++;
1127 		}
1128 	}
1129 
1130 out:
1131 	qup->blk.data_len -= total;
1132 
1133 	return ret;
1134 }
1135 
1136 static int qup_i2c_read_one_v2(struct qup_i2c_dev *qup, struct i2c_msg *msg)
1137 {
1138 	int ret = 0;
1139 
1140 	qup->msg = msg;
1141 	qup->pos  = 0;
1142 	enable_irq(qup->irq);
1143 	qup_i2c_set_blk_data(qup, msg);
1144 	qup_i2c_set_read_mode_v2(qup, msg->len);
1145 
1146 	ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
1147 	if (ret)
1148 		goto err;
1149 
1150 	writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
1151 
1152 	do {
1153 		ret = qup_i2c_issue_xfer_v2(qup, msg);
1154 		if (ret)
1155 			goto err;
1156 
1157 		ret = qup_i2c_wait_for_complete(qup, msg);
1158 		if (ret)
1159 			goto err;
1160 
1161 		ret = qup_i2c_read_fifo_v2(qup, msg);
1162 		if (ret)
1163 			goto err;
1164 
1165 		qup->blk.pos++;
1166 
1167 		/* Handle SMBus block read length */
1168 		if (qup_i2c_check_msg_len(msg) && (msg->len == 1)) {
1169 			if (msg->buf[0] > I2C_SMBUS_BLOCK_MAX) {
1170 				ret = -EPROTO;
1171 				goto err;
1172 			}
1173 			msg->len += msg->buf[0];
1174 			qup->pos = 0;
1175 			qup_i2c_set_blk_data(qup, msg);
1176 			/* set tag length for block read */
1177 			qup->blk.tx_tag_len = 2;
1178 			qup_i2c_set_read_mode_v2(qup, msg->buf[0]);
1179 		}
1180 	} while (qup->blk.pos < qup->blk.count);
1181 
1182 err:
1183 	disable_irq(qup->irq);
1184 	qup->msg = NULL;
1185 
1186 	return ret;
1187 }
1188 
1189 static int qup_i2c_read_one(struct qup_i2c_dev *qup, struct i2c_msg *msg)
1190 {
1191 	int ret;
1192 
1193 	qup->msg = msg;
1194 	qup->pos  = 0;
1195 
1196 	enable_irq(qup->irq);
1197 	qup_i2c_set_read_mode(qup, msg->len);
1198 
1199 	ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
1200 	if (ret)
1201 		goto err;
1202 
1203 	writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
1204 
1205 	ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
1206 	if (ret)
1207 		goto err;
1208 
1209 	qup_i2c_issue_read(qup, msg);
1210 
1211 	ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
1212 	if (ret)
1213 		goto err;
1214 
1215 	do {
1216 		ret = qup_i2c_wait_for_complete(qup, msg);
1217 		if (ret)
1218 			goto err;
1219 
1220 		ret = qup_i2c_read_fifo(qup, msg);
1221 		if (ret)
1222 			goto err;
1223 	} while (qup->pos < msg->len);
1224 
1225 err:
1226 	disable_irq(qup->irq);
1227 	qup->msg = NULL;
1228 
1229 	return ret;
1230 }
1231 
1232 static int qup_i2c_xfer(struct i2c_adapter *adap,
1233 			struct i2c_msg msgs[],
1234 			int num)
1235 {
1236 	struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
1237 	int ret, idx;
1238 
1239 	ret = pm_runtime_get_sync(qup->dev);
1240 	if (ret < 0)
1241 		goto out;
1242 
1243 	qup->bus_err = 0;
1244 	qup->qup_err = 0;
1245 
1246 	writel(1, qup->base + QUP_SW_RESET);
1247 	ret = qup_i2c_poll_state(qup, QUP_RESET_STATE);
1248 	if (ret)
1249 		goto out;
1250 
1251 	/* Configure QUP as I2C mini core */
1252 	writel(I2C_MINI_CORE | I2C_N_VAL, qup->base + QUP_CONFIG);
1253 
1254 	for (idx = 0; idx < num; idx++) {
1255 		if (msgs[idx].len == 0) {
1256 			ret = -EINVAL;
1257 			goto out;
1258 		}
1259 
1260 		if (qup_i2c_poll_state_i2c_master(qup)) {
1261 			ret = -EIO;
1262 			goto out;
1263 		}
1264 
1265 		if (qup_i2c_check_msg_len(&msgs[idx])) {
1266 			ret = -EINVAL;
1267 			goto out;
1268 		}
1269 
1270 		if (msgs[idx].flags & I2C_M_RD)
1271 			ret = qup_i2c_read_one(qup, &msgs[idx]);
1272 		else
1273 			ret = qup_i2c_write_one(qup, &msgs[idx]);
1274 
1275 		if (ret)
1276 			break;
1277 
1278 		ret = qup_i2c_change_state(qup, QUP_RESET_STATE);
1279 		if (ret)
1280 			break;
1281 	}
1282 
1283 	if (ret == 0)
1284 		ret = num;
1285 out:
1286 
1287 	pm_runtime_mark_last_busy(qup->dev);
1288 	pm_runtime_put_autosuspend(qup->dev);
1289 
1290 	return ret;
1291 }
1292 
1293 static int qup_i2c_xfer_v2(struct i2c_adapter *adap,
1294 			   struct i2c_msg msgs[],
1295 			   int num)
1296 {
1297 	struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
1298 	int ret, len, idx = 0, use_dma = 0;
1299 
1300 	qup->bus_err = 0;
1301 	qup->qup_err = 0;
1302 
1303 	ret = pm_runtime_get_sync(qup->dev);
1304 	if (ret < 0)
1305 		goto out;
1306 
1307 	writel(1, qup->base + QUP_SW_RESET);
1308 	ret = qup_i2c_poll_state(qup, QUP_RESET_STATE);
1309 	if (ret)
1310 		goto out;
1311 
1312 	/* Configure QUP as I2C mini core */
1313 	writel(I2C_MINI_CORE | I2C_N_VAL_V2, qup->base + QUP_CONFIG);
1314 	writel(QUP_V2_TAGS_EN, qup->base + QUP_I2C_MASTER_GEN);
1315 
1316 	if ((qup->is_dma)) {
1317 		/* All i2c_msgs should be transferred using either dma or cpu */
1318 		for (idx = 0; idx < num; idx++) {
1319 			if (msgs[idx].len == 0) {
1320 				ret = -EINVAL;
1321 				goto out;
1322 			}
1323 
1324 			len = (msgs[idx].len > qup->out_fifo_sz) ||
1325 			      (msgs[idx].len > qup->in_fifo_sz);
1326 
1327 			if ((!is_vmalloc_addr(msgs[idx].buf)) && len) {
1328 				use_dma = 1;
1329 			 } else {
1330 				use_dma = 0;
1331 				break;
1332 			}
1333 		}
1334 	}
1335 
1336 	idx = 0;
1337 
1338 	do {
1339 		if (msgs[idx].len == 0) {
1340 			ret = -EINVAL;
1341 			goto out;
1342 		}
1343 
1344 		if (qup_i2c_poll_state_i2c_master(qup)) {
1345 			ret = -EIO;
1346 			goto out;
1347 		}
1348 
1349 		qup->is_last = (idx == (num - 1));
1350 		if (idx)
1351 			qup->config_run = QUP_I2C_MX_CONFIG_DURING_RUN;
1352 		else
1353 			qup->config_run = 0;
1354 
1355 		reinit_completion(&qup->xfer);
1356 
1357 		if (use_dma) {
1358 			ret = qup_i2c_bam_xfer(adap, &msgs[idx], num);
1359 		} else {
1360 			if (msgs[idx].flags & I2C_M_RD)
1361 				ret = qup_i2c_read_one_v2(qup, &msgs[idx]);
1362 			else
1363 				ret = qup_i2c_write_one_v2(qup, &msgs[idx]);
1364 		}
1365 	} while ((idx++ < (num - 1)) && !use_dma && !ret);
1366 
1367 	if (!ret)
1368 		ret = qup_i2c_change_state(qup, QUP_RESET_STATE);
1369 
1370 	if (ret == 0)
1371 		ret = num;
1372 out:
1373 	pm_runtime_mark_last_busy(qup->dev);
1374 	pm_runtime_put_autosuspend(qup->dev);
1375 
1376 	return ret;
1377 }
1378 
1379 static u32 qup_i2c_func(struct i2c_adapter *adap)
1380 {
1381 	return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
1382 }
1383 
1384 static const struct i2c_algorithm qup_i2c_algo = {
1385 	.master_xfer	= qup_i2c_xfer,
1386 	.functionality	= qup_i2c_func,
1387 };
1388 
1389 static const struct i2c_algorithm qup_i2c_algo_v2 = {
1390 	.master_xfer	= qup_i2c_xfer_v2,
1391 	.functionality	= qup_i2c_func,
1392 };
1393 
1394 /*
1395  * The QUP block will issue a NACK and STOP on the bus when reaching
1396  * the end of the read, the length of the read is specified as one byte
1397  * which limits the possible read to 256 (QUP_READ_LIMIT) bytes.
1398  */
1399 static struct i2c_adapter_quirks qup_i2c_quirks = {
1400 	.max_read_len = QUP_READ_LIMIT,
1401 };
1402 
1403 static void qup_i2c_enable_clocks(struct qup_i2c_dev *qup)
1404 {
1405 	clk_prepare_enable(qup->clk);
1406 	clk_prepare_enable(qup->pclk);
1407 }
1408 
1409 static void qup_i2c_disable_clocks(struct qup_i2c_dev *qup)
1410 {
1411 	u32 config;
1412 
1413 	qup_i2c_change_state(qup, QUP_RESET_STATE);
1414 	clk_disable_unprepare(qup->clk);
1415 	config = readl(qup->base + QUP_CONFIG);
1416 	config |= QUP_CLOCK_AUTO_GATE;
1417 	writel(config, qup->base + QUP_CONFIG);
1418 	clk_disable_unprepare(qup->pclk);
1419 }
1420 
1421 static int qup_i2c_probe(struct platform_device *pdev)
1422 {
1423 	static const int blk_sizes[] = {4, 16, 32};
1424 	struct qup_i2c_dev *qup;
1425 	unsigned long one_bit_t;
1426 	struct resource *res;
1427 	u32 io_mode, hw_ver, size;
1428 	int ret, fs_div, hs_div;
1429 	u32 src_clk_freq = DEFAULT_SRC_CLK;
1430 	u32 clk_freq = DEFAULT_CLK_FREQ;
1431 	int blocks;
1432 
1433 	qup = devm_kzalloc(&pdev->dev, sizeof(*qup), GFP_KERNEL);
1434 	if (!qup)
1435 		return -ENOMEM;
1436 
1437 	qup->dev = &pdev->dev;
1438 	init_completion(&qup->xfer);
1439 	platform_set_drvdata(pdev, qup);
1440 
1441 	ret = device_property_read_u32(qup->dev, "clock-frequency", &clk_freq);
1442 	if (ret) {
1443 		dev_notice(qup->dev, "using default clock-frequency %d",
1444 			DEFAULT_CLK_FREQ);
1445 	}
1446 
1447 	if (of_device_is_compatible(pdev->dev.of_node, "qcom,i2c-qup-v1.1.1")) {
1448 		qup->adap.algo = &qup_i2c_algo;
1449 		qup->adap.quirks = &qup_i2c_quirks;
1450 	} else {
1451 		qup->adap.algo = &qup_i2c_algo_v2;
1452 		ret = qup_i2c_req_dma(qup);
1453 
1454 		if (ret == -EPROBE_DEFER)
1455 			goto fail_dma;
1456 		else if (ret != 0)
1457 			goto nodma;
1458 
1459 		blocks = (MX_BLOCKS << 1) + 1;
1460 		qup->btx.sg = devm_kzalloc(&pdev->dev,
1461 					   sizeof(*qup->btx.sg) * blocks,
1462 					   GFP_KERNEL);
1463 		if (!qup->btx.sg) {
1464 			ret = -ENOMEM;
1465 			goto fail_dma;
1466 		}
1467 		sg_init_table(qup->btx.sg, blocks);
1468 
1469 		qup->brx.sg = devm_kzalloc(&pdev->dev,
1470 					   sizeof(*qup->brx.sg) * blocks,
1471 					   GFP_KERNEL);
1472 		if (!qup->brx.sg) {
1473 			ret = -ENOMEM;
1474 			goto fail_dma;
1475 		}
1476 		sg_init_table(qup->brx.sg, blocks);
1477 
1478 		/* 2 tag bytes for each block + 5 for start, stop tags */
1479 		size = blocks * 2 + 5;
1480 
1481 		qup->start_tag.start = devm_kzalloc(&pdev->dev,
1482 						    size, GFP_KERNEL);
1483 		if (!qup->start_tag.start) {
1484 			ret = -ENOMEM;
1485 			goto fail_dma;
1486 		}
1487 
1488 		qup->brx.tag.start = devm_kzalloc(&pdev->dev, 2, GFP_KERNEL);
1489 		if (!qup->brx.tag.start) {
1490 			ret = -ENOMEM;
1491 			goto fail_dma;
1492 		}
1493 
1494 		qup->btx.tag.start = devm_kzalloc(&pdev->dev, 2, GFP_KERNEL);
1495 		if (!qup->btx.tag.start) {
1496 			ret = -ENOMEM;
1497 			goto fail_dma;
1498 		}
1499 		qup->is_dma = true;
1500 	}
1501 
1502 nodma:
1503 	/* We support frequencies up to FAST Mode (400KHz) */
1504 	if (!clk_freq || clk_freq > 400000) {
1505 		dev_err(qup->dev, "clock frequency not supported %d\n",
1506 			clk_freq);
1507 		return -EINVAL;
1508 	}
1509 
1510 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1511 	qup->base = devm_ioremap_resource(qup->dev, res);
1512 	if (IS_ERR(qup->base))
1513 		return PTR_ERR(qup->base);
1514 
1515 	qup->irq = platform_get_irq(pdev, 0);
1516 	if (qup->irq < 0) {
1517 		dev_err(qup->dev, "No IRQ defined\n");
1518 		return qup->irq;
1519 	}
1520 
1521 	if (has_acpi_companion(qup->dev)) {
1522 		ret = device_property_read_u32(qup->dev,
1523 				"src-clock-hz", &src_clk_freq);
1524 		if (ret) {
1525 			dev_notice(qup->dev, "using default src-clock-hz %d",
1526 				DEFAULT_SRC_CLK);
1527 		}
1528 		ACPI_COMPANION_SET(&qup->adap.dev, ACPI_COMPANION(qup->dev));
1529 	} else {
1530 		qup->clk = devm_clk_get(qup->dev, "core");
1531 		if (IS_ERR(qup->clk)) {
1532 			dev_err(qup->dev, "Could not get core clock\n");
1533 			return PTR_ERR(qup->clk);
1534 		}
1535 
1536 		qup->pclk = devm_clk_get(qup->dev, "iface");
1537 		if (IS_ERR(qup->pclk)) {
1538 			dev_err(qup->dev, "Could not get iface clock\n");
1539 			return PTR_ERR(qup->pclk);
1540 		}
1541 		qup_i2c_enable_clocks(qup);
1542 		src_clk_freq = clk_get_rate(qup->clk);
1543 	}
1544 
1545 	/*
1546 	 * Bootloaders might leave a pending interrupt on certain QUP's,
1547 	 * so we reset the core before registering for interrupts.
1548 	 */
1549 	writel(1, qup->base + QUP_SW_RESET);
1550 	ret = qup_i2c_poll_state_valid(qup);
1551 	if (ret)
1552 		goto fail;
1553 
1554 	ret = devm_request_irq(qup->dev, qup->irq, qup_i2c_interrupt,
1555 			       IRQF_TRIGGER_HIGH, "i2c_qup", qup);
1556 	if (ret) {
1557 		dev_err(qup->dev, "Request %d IRQ failed\n", qup->irq);
1558 		goto fail;
1559 	}
1560 	disable_irq(qup->irq);
1561 
1562 	hw_ver = readl(qup->base + QUP_HW_VERSION);
1563 	dev_dbg(qup->dev, "Revision %x\n", hw_ver);
1564 
1565 	io_mode = readl(qup->base + QUP_IO_MODE);
1566 
1567 	/*
1568 	 * The block/fifo size w.r.t. 'actual data' is 1/2 due to 'tag'
1569 	 * associated with each byte written/received
1570 	 */
1571 	size = QUP_OUTPUT_BLOCK_SIZE(io_mode);
1572 	if (size >= ARRAY_SIZE(blk_sizes)) {
1573 		ret = -EIO;
1574 		goto fail;
1575 	}
1576 	qup->out_blk_sz = blk_sizes[size] / 2;
1577 
1578 	size = QUP_INPUT_BLOCK_SIZE(io_mode);
1579 	if (size >= ARRAY_SIZE(blk_sizes)) {
1580 		ret = -EIO;
1581 		goto fail;
1582 	}
1583 	qup->in_blk_sz = blk_sizes[size] / 2;
1584 
1585 	size = QUP_OUTPUT_FIFO_SIZE(io_mode);
1586 	qup->out_fifo_sz = qup->out_blk_sz * (2 << size);
1587 
1588 	size = QUP_INPUT_FIFO_SIZE(io_mode);
1589 	qup->in_fifo_sz = qup->in_blk_sz * (2 << size);
1590 
1591 	fs_div = ((src_clk_freq / clk_freq) / 2) - 3;
1592 	hs_div = 3;
1593 	qup->clk_ctl = (hs_div << 8) | (fs_div & 0xff);
1594 
1595 	/*
1596 	 * Time it takes for a byte to be clocked out on the bus.
1597 	 * Each byte takes 9 clock cycles (8 bits + 1 ack).
1598 	 */
1599 	one_bit_t = (USEC_PER_SEC / clk_freq) + 1;
1600 	qup->one_byte_t = one_bit_t * 9;
1601 
1602 	dev_dbg(qup->dev, "IN:block:%d, fifo:%d, OUT:block:%d, fifo:%d\n",
1603 		qup->in_blk_sz, qup->in_fifo_sz,
1604 		qup->out_blk_sz, qup->out_fifo_sz);
1605 
1606 	i2c_set_adapdata(&qup->adap, qup);
1607 	qup->adap.dev.parent = qup->dev;
1608 	qup->adap.dev.of_node = pdev->dev.of_node;
1609 	qup->is_last = true;
1610 
1611 	strlcpy(qup->adap.name, "QUP I2C adapter", sizeof(qup->adap.name));
1612 
1613 	pm_runtime_set_autosuspend_delay(qup->dev, MSEC_PER_SEC);
1614 	pm_runtime_use_autosuspend(qup->dev);
1615 	pm_runtime_set_active(qup->dev);
1616 	pm_runtime_enable(qup->dev);
1617 
1618 	ret = i2c_add_adapter(&qup->adap);
1619 	if (ret)
1620 		goto fail_runtime;
1621 
1622 	return 0;
1623 
1624 fail_runtime:
1625 	pm_runtime_disable(qup->dev);
1626 	pm_runtime_set_suspended(qup->dev);
1627 fail:
1628 	qup_i2c_disable_clocks(qup);
1629 fail_dma:
1630 	if (qup->btx.dma)
1631 		dma_release_channel(qup->btx.dma);
1632 	if (qup->brx.dma)
1633 		dma_release_channel(qup->brx.dma);
1634 	return ret;
1635 }
1636 
1637 static int qup_i2c_remove(struct platform_device *pdev)
1638 {
1639 	struct qup_i2c_dev *qup = platform_get_drvdata(pdev);
1640 
1641 	if (qup->is_dma) {
1642 		dma_release_channel(qup->btx.dma);
1643 		dma_release_channel(qup->brx.dma);
1644 	}
1645 
1646 	disable_irq(qup->irq);
1647 	qup_i2c_disable_clocks(qup);
1648 	i2c_del_adapter(&qup->adap);
1649 	pm_runtime_disable(qup->dev);
1650 	pm_runtime_set_suspended(qup->dev);
1651 	return 0;
1652 }
1653 
1654 #ifdef CONFIG_PM
1655 static int qup_i2c_pm_suspend_runtime(struct device *device)
1656 {
1657 	struct qup_i2c_dev *qup = dev_get_drvdata(device);
1658 
1659 	dev_dbg(device, "pm_runtime: suspending...\n");
1660 	qup_i2c_disable_clocks(qup);
1661 	return 0;
1662 }
1663 
1664 static int qup_i2c_pm_resume_runtime(struct device *device)
1665 {
1666 	struct qup_i2c_dev *qup = dev_get_drvdata(device);
1667 
1668 	dev_dbg(device, "pm_runtime: resuming...\n");
1669 	qup_i2c_enable_clocks(qup);
1670 	return 0;
1671 }
1672 #endif
1673 
1674 #ifdef CONFIG_PM_SLEEP
1675 static int qup_i2c_suspend(struct device *device)
1676 {
1677 	if (!pm_runtime_suspended(device))
1678 		return qup_i2c_pm_suspend_runtime(device);
1679 	return 0;
1680 }
1681 
1682 static int qup_i2c_resume(struct device *device)
1683 {
1684 	qup_i2c_pm_resume_runtime(device);
1685 	pm_runtime_mark_last_busy(device);
1686 	pm_request_autosuspend(device);
1687 	return 0;
1688 }
1689 #endif
1690 
1691 static const struct dev_pm_ops qup_i2c_qup_pm_ops = {
1692 	SET_SYSTEM_SLEEP_PM_OPS(
1693 		qup_i2c_suspend,
1694 		qup_i2c_resume)
1695 	SET_RUNTIME_PM_OPS(
1696 		qup_i2c_pm_suspend_runtime,
1697 		qup_i2c_pm_resume_runtime,
1698 		NULL)
1699 };
1700 
1701 static const struct of_device_id qup_i2c_dt_match[] = {
1702 	{ .compatible = "qcom,i2c-qup-v1.1.1" },
1703 	{ .compatible = "qcom,i2c-qup-v2.1.1" },
1704 	{ .compatible = "qcom,i2c-qup-v2.2.1" },
1705 	{}
1706 };
1707 MODULE_DEVICE_TABLE(of, qup_i2c_dt_match);
1708 
1709 #if IS_ENABLED(CONFIG_ACPI)
1710 static const struct acpi_device_id qup_i2c_acpi_match[] = {
1711 	{ "QCOM8010"},
1712 	{ },
1713 };
1714 MODULE_DEVICE_TABLE(acpi, qup_i2c_acpi_match);
1715 #endif
1716 
1717 static struct platform_driver qup_i2c_driver = {
1718 	.probe  = qup_i2c_probe,
1719 	.remove = qup_i2c_remove,
1720 	.driver = {
1721 		.name = "i2c_qup",
1722 		.pm = &qup_i2c_qup_pm_ops,
1723 		.of_match_table = qup_i2c_dt_match,
1724 		.acpi_match_table = ACPI_PTR(qup_i2c_acpi_match),
1725 	},
1726 };
1727 
1728 module_platform_driver(qup_i2c_driver);
1729 
1730 MODULE_LICENSE("GPL v2");
1731 MODULE_ALIAS("platform:i2c_qup");
1732