xref: /openbmc/linux/drivers/i2c/busses/i2c-qup.c (revision 1a59d1b8)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2009-2013, 2016-2018, The Linux Foundation. All rights reserved.
4  * Copyright (c) 2014, Sony Mobile Communications AB.
5  *
6  */
7 
8 #include <linux/acpi.h>
9 #include <linux/atomic.h>
10 #include <linux/clk.h>
11 #include <linux/delay.h>
12 #include <linux/dmaengine.h>
13 #include <linux/dmapool.h>
14 #include <linux/dma-mapping.h>
15 #include <linux/err.h>
16 #include <linux/i2c.h>
17 #include <linux/interrupt.h>
18 #include <linux/io.h>
19 #include <linux/module.h>
20 #include <linux/of.h>
21 #include <linux/platform_device.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/scatterlist.h>
24 
25 /* QUP Registers */
26 #define QUP_CONFIG		0x000
27 #define QUP_STATE		0x004
28 #define QUP_IO_MODE		0x008
29 #define QUP_SW_RESET		0x00c
30 #define QUP_OPERATIONAL		0x018
31 #define QUP_ERROR_FLAGS		0x01c
32 #define QUP_ERROR_FLAGS_EN	0x020
33 #define QUP_OPERATIONAL_MASK	0x028
34 #define QUP_HW_VERSION		0x030
35 #define QUP_MX_OUTPUT_CNT	0x100
36 #define QUP_OUT_FIFO_BASE	0x110
37 #define QUP_MX_WRITE_CNT	0x150
38 #define QUP_MX_INPUT_CNT	0x200
39 #define QUP_MX_READ_CNT		0x208
40 #define QUP_IN_FIFO_BASE	0x218
41 #define QUP_I2C_CLK_CTL		0x400
42 #define QUP_I2C_STATUS		0x404
43 #define QUP_I2C_MASTER_GEN	0x408
44 
45 /* QUP States and reset values */
46 #define QUP_RESET_STATE		0
47 #define QUP_RUN_STATE		1
48 #define QUP_PAUSE_STATE		3
49 #define QUP_STATE_MASK		3
50 
51 #define QUP_STATE_VALID		BIT(2)
52 #define QUP_I2C_MAST_GEN	BIT(4)
53 #define QUP_I2C_FLUSH		BIT(6)
54 
55 #define QUP_OPERATIONAL_RESET	0x000ff0
56 #define QUP_I2C_STATUS_RESET	0xfffffc
57 
58 /* QUP OPERATIONAL FLAGS */
59 #define QUP_I2C_NACK_FLAG	BIT(3)
60 #define QUP_OUT_NOT_EMPTY	BIT(4)
61 #define QUP_IN_NOT_EMPTY	BIT(5)
62 #define QUP_OUT_FULL		BIT(6)
63 #define QUP_OUT_SVC_FLAG	BIT(8)
64 #define QUP_IN_SVC_FLAG		BIT(9)
65 #define QUP_MX_OUTPUT_DONE	BIT(10)
66 #define QUP_MX_INPUT_DONE	BIT(11)
67 #define OUT_BLOCK_WRITE_REQ	BIT(12)
68 #define IN_BLOCK_READ_REQ	BIT(13)
69 
70 /* I2C mini core related values */
71 #define QUP_NO_INPUT		BIT(7)
72 #define QUP_CLOCK_AUTO_GATE	BIT(13)
73 #define I2C_MINI_CORE		(2 << 8)
74 #define I2C_N_VAL		15
75 #define I2C_N_VAL_V2		7
76 
77 /* Most significant word offset in FIFO port */
78 #define QUP_MSW_SHIFT		(I2C_N_VAL + 1)
79 
80 /* Packing/Unpacking words in FIFOs, and IO modes */
81 #define QUP_OUTPUT_BLK_MODE	(1 << 10)
82 #define QUP_OUTPUT_BAM_MODE	(3 << 10)
83 #define QUP_INPUT_BLK_MODE	(1 << 12)
84 #define QUP_INPUT_BAM_MODE	(3 << 12)
85 #define QUP_BAM_MODE		(QUP_OUTPUT_BAM_MODE | QUP_INPUT_BAM_MODE)
86 #define QUP_UNPACK_EN		BIT(14)
87 #define QUP_PACK_EN		BIT(15)
88 
89 #define QUP_REPACK_EN		(QUP_UNPACK_EN | QUP_PACK_EN)
90 #define QUP_V2_TAGS_EN		1
91 
92 #define QUP_OUTPUT_BLOCK_SIZE(x)(((x) >> 0) & 0x03)
93 #define QUP_OUTPUT_FIFO_SIZE(x)	(((x) >> 2) & 0x07)
94 #define QUP_INPUT_BLOCK_SIZE(x)	(((x) >> 5) & 0x03)
95 #define QUP_INPUT_FIFO_SIZE(x)	(((x) >> 7) & 0x07)
96 
97 /* QUP tags */
98 #define QUP_TAG_START		(1 << 8)
99 #define QUP_TAG_DATA		(2 << 8)
100 #define QUP_TAG_STOP		(3 << 8)
101 #define QUP_TAG_REC		(4 << 8)
102 #define QUP_BAM_INPUT_EOT		0x93
103 #define QUP_BAM_FLUSH_STOP		0x96
104 
105 /* QUP v2 tags */
106 #define QUP_TAG_V2_START               0x81
107 #define QUP_TAG_V2_DATAWR              0x82
108 #define QUP_TAG_V2_DATAWR_STOP         0x83
109 #define QUP_TAG_V2_DATARD              0x85
110 #define QUP_TAG_V2_DATARD_NACK         0x86
111 #define QUP_TAG_V2_DATARD_STOP         0x87
112 
113 /* Status, Error flags */
114 #define I2C_STATUS_WR_BUFFER_FULL	BIT(0)
115 #define I2C_STATUS_BUS_ACTIVE		BIT(8)
116 #define I2C_STATUS_ERROR_MASK		0x38000fc
117 #define QUP_STATUS_ERROR_FLAGS		0x7c
118 
119 #define QUP_READ_LIMIT			256
120 #define SET_BIT				0x1
121 #define RESET_BIT			0x0
122 #define ONE_BYTE			0x1
123 #define QUP_I2C_MX_CONFIG_DURING_RUN   BIT(31)
124 
125 /* Maximum transfer length for single DMA descriptor */
126 #define MX_TX_RX_LEN			SZ_64K
127 #define MX_BLOCKS			(MX_TX_RX_LEN / QUP_READ_LIMIT)
128 /* Maximum transfer length for all DMA descriptors */
129 #define MX_DMA_TX_RX_LEN		(2 * MX_TX_RX_LEN)
130 #define MX_DMA_BLOCKS			(MX_DMA_TX_RX_LEN / QUP_READ_LIMIT)
131 
132 /*
133  * Minimum transfer timeout for i2c transfers in seconds. It will be added on
134  * the top of maximum transfer time calculated from i2c bus speed to compensate
135  * the overheads.
136  */
137 #define TOUT_MIN			2
138 
139 /* I2C Frequency Modes */
140 #define I2C_STANDARD_FREQ		100000
141 #define I2C_FAST_MODE_FREQ		400000
142 #define I2C_FAST_MODE_PLUS_FREQ		1000000
143 
144 /* Default values. Use these if FW query fails */
145 #define DEFAULT_CLK_FREQ I2C_STANDARD_FREQ
146 #define DEFAULT_SRC_CLK 20000000
147 
148 /*
149  * Max tags length (start, stop and maximum 2 bytes address) for each QUP
150  * data transfer
151  */
152 #define QUP_MAX_TAGS_LEN		4
153 /* Max data length for each DATARD tags */
154 #define RECV_MAX_DATA_LEN		254
155 /* TAG length for DATA READ in RX FIFO  */
156 #define READ_RX_TAGS_LEN		2
157 
158 static unsigned int scl_freq;
159 module_param_named(scl_freq, scl_freq, uint, 0444);
160 MODULE_PARM_DESC(scl_freq, "SCL frequency override");
161 
162 /*
163  * count: no of blocks
164  * pos: current block number
165  * tx_tag_len: tx tag length for current block
166  * rx_tag_len: rx tag length for current block
167  * data_len: remaining data length for current message
168  * cur_blk_len: data length for current block
169  * total_tx_len: total tx length including tag bytes for current QUP transfer
170  * total_rx_len: total rx length including tag bytes for current QUP transfer
171  * tx_fifo_data_pos: current byte number in TX FIFO word
172  * tx_fifo_free: number of free bytes in current QUP block write.
173  * rx_fifo_data_pos: current byte number in RX FIFO word
174  * fifo_available: number of available bytes in RX FIFO for current
175  *		   QUP block read
176  * tx_fifo_data: QUP TX FIFO write works on word basis (4 bytes). New byte write
177  *		 to TX FIFO will be appended in this data and will be written to
178  *		 TX FIFO when all the 4 bytes are available.
179  * rx_fifo_data: QUP RX FIFO read works on word basis (4 bytes). This will
180  *		 contains the 4 bytes of RX data.
181  * cur_data: pointer to tell cur data position for current message
182  * cur_tx_tags: pointer to tell cur position in tags
183  * tx_tags_sent: all tx tag bytes have been written in FIFO word
184  * send_last_word: for tx FIFO, last word send is pending in current block
185  * rx_bytes_read: if all the bytes have been read from rx FIFO.
186  * rx_tags_fetched: all the rx tag bytes have been fetched from rx fifo word
187  * is_tx_blk_mode: whether tx uses block or FIFO mode in case of non BAM xfer.
188  * is_rx_blk_mode: whether rx uses block or FIFO mode in case of non BAM xfer.
189  * tags: contains tx tag bytes for current QUP transfer
190  */
191 struct qup_i2c_block {
192 	int		count;
193 	int		pos;
194 	int		tx_tag_len;
195 	int		rx_tag_len;
196 	int		data_len;
197 	int		cur_blk_len;
198 	int		total_tx_len;
199 	int		total_rx_len;
200 	int		tx_fifo_data_pos;
201 	int		tx_fifo_free;
202 	int		rx_fifo_data_pos;
203 	int		fifo_available;
204 	u32		tx_fifo_data;
205 	u32		rx_fifo_data;
206 	u8		*cur_data;
207 	u8		*cur_tx_tags;
208 	bool		tx_tags_sent;
209 	bool		send_last_word;
210 	bool		rx_tags_fetched;
211 	bool		rx_bytes_read;
212 	bool		is_tx_blk_mode;
213 	bool		is_rx_blk_mode;
214 	u8		tags[6];
215 };
216 
217 struct qup_i2c_tag {
218 	u8 *start;
219 	dma_addr_t addr;
220 };
221 
222 struct qup_i2c_bam {
223 	struct	qup_i2c_tag tag;
224 	struct	dma_chan *dma;
225 	struct	scatterlist *sg;
226 	unsigned int sg_cnt;
227 };
228 
229 struct qup_i2c_dev {
230 	struct device		*dev;
231 	void __iomem		*base;
232 	int			irq;
233 	struct clk		*clk;
234 	struct clk		*pclk;
235 	struct i2c_adapter	adap;
236 
237 	int			clk_ctl;
238 	int			out_fifo_sz;
239 	int			in_fifo_sz;
240 	int			out_blk_sz;
241 	int			in_blk_sz;
242 
243 	int			blk_xfer_limit;
244 	unsigned long		one_byte_t;
245 	unsigned long		xfer_timeout;
246 	struct qup_i2c_block	blk;
247 
248 	struct i2c_msg		*msg;
249 	/* Current posion in user message buffer */
250 	int			pos;
251 	/* I2C protocol errors */
252 	u32			bus_err;
253 	/* QUP core errors */
254 	u32			qup_err;
255 
256 	/* To check if this is the last msg */
257 	bool			is_last;
258 	bool			is_smbus_read;
259 
260 	/* To configure when bus is in run state */
261 	u32			config_run;
262 
263 	/* dma parameters */
264 	bool			is_dma;
265 	/* To check if the current transfer is using DMA */
266 	bool			use_dma;
267 	unsigned int		max_xfer_sg_len;
268 	unsigned int		tag_buf_pos;
269 	/* The threshold length above which block mode will be used */
270 	unsigned int		blk_mode_threshold;
271 	struct			dma_pool *dpool;
272 	struct			qup_i2c_tag start_tag;
273 	struct			qup_i2c_bam brx;
274 	struct			qup_i2c_bam btx;
275 
276 	struct completion	xfer;
277 	/* function to write data in tx fifo */
278 	void (*write_tx_fifo)(struct qup_i2c_dev *qup);
279 	/* function to read data from rx fifo */
280 	void (*read_rx_fifo)(struct qup_i2c_dev *qup);
281 	/* function to write tags in tx fifo for i2c read transfer */
282 	void (*write_rx_tags)(struct qup_i2c_dev *qup);
283 };
284 
285 static irqreturn_t qup_i2c_interrupt(int irq, void *dev)
286 {
287 	struct qup_i2c_dev *qup = dev;
288 	struct qup_i2c_block *blk = &qup->blk;
289 	u32 bus_err;
290 	u32 qup_err;
291 	u32 opflags;
292 
293 	bus_err = readl(qup->base + QUP_I2C_STATUS);
294 	qup_err = readl(qup->base + QUP_ERROR_FLAGS);
295 	opflags = readl(qup->base + QUP_OPERATIONAL);
296 
297 	if (!qup->msg) {
298 		/* Clear Error interrupt */
299 		writel(QUP_RESET_STATE, qup->base + QUP_STATE);
300 		return IRQ_HANDLED;
301 	}
302 
303 	bus_err &= I2C_STATUS_ERROR_MASK;
304 	qup_err &= QUP_STATUS_ERROR_FLAGS;
305 
306 	/* Clear the error bits in QUP_ERROR_FLAGS */
307 	if (qup_err)
308 		writel(qup_err, qup->base + QUP_ERROR_FLAGS);
309 
310 	/* Clear the error bits in QUP_I2C_STATUS */
311 	if (bus_err)
312 		writel(bus_err, qup->base + QUP_I2C_STATUS);
313 
314 	/*
315 	 * Check for BAM mode and returns if already error has come for current
316 	 * transfer. In Error case, sometimes, QUP generates more than one
317 	 * interrupt.
318 	 */
319 	if (qup->use_dma && (qup->qup_err || qup->bus_err))
320 		return IRQ_HANDLED;
321 
322 	/* Reset the QUP State in case of error */
323 	if (qup_err || bus_err) {
324 		/*
325 		 * Don’t reset the QUP state in case of BAM mode. The BAM
326 		 * flush operation needs to be scheduled in transfer function
327 		 * which will clear the remaining schedule descriptors in BAM
328 		 * HW FIFO and generates the BAM interrupt.
329 		 */
330 		if (!qup->use_dma)
331 			writel(QUP_RESET_STATE, qup->base + QUP_STATE);
332 		goto done;
333 	}
334 
335 	if (opflags & QUP_OUT_SVC_FLAG) {
336 		writel(QUP_OUT_SVC_FLAG, qup->base + QUP_OPERATIONAL);
337 
338 		if (opflags & OUT_BLOCK_WRITE_REQ) {
339 			blk->tx_fifo_free += qup->out_blk_sz;
340 			if (qup->msg->flags & I2C_M_RD)
341 				qup->write_rx_tags(qup);
342 			else
343 				qup->write_tx_fifo(qup);
344 		}
345 	}
346 
347 	if (opflags & QUP_IN_SVC_FLAG) {
348 		writel(QUP_IN_SVC_FLAG, qup->base + QUP_OPERATIONAL);
349 
350 		if (!blk->is_rx_blk_mode) {
351 			blk->fifo_available += qup->in_fifo_sz;
352 			qup->read_rx_fifo(qup);
353 		} else if (opflags & IN_BLOCK_READ_REQ) {
354 			blk->fifo_available += qup->in_blk_sz;
355 			qup->read_rx_fifo(qup);
356 		}
357 	}
358 
359 	if (qup->msg->flags & I2C_M_RD) {
360 		if (!blk->rx_bytes_read)
361 			return IRQ_HANDLED;
362 	} else {
363 		/*
364 		 * Ideally, QUP_MAX_OUTPUT_DONE_FLAG should be checked
365 		 * for FIFO mode also. But, QUP_MAX_OUTPUT_DONE_FLAG lags
366 		 * behind QUP_OUTPUT_SERVICE_FLAG sometimes. The only reason
367 		 * of interrupt for write message in FIFO mode is
368 		 * QUP_MAX_OUTPUT_DONE_FLAG condition.
369 		 */
370 		if (blk->is_tx_blk_mode && !(opflags & QUP_MX_OUTPUT_DONE))
371 			return IRQ_HANDLED;
372 	}
373 
374 done:
375 	qup->qup_err = qup_err;
376 	qup->bus_err = bus_err;
377 	complete(&qup->xfer);
378 	return IRQ_HANDLED;
379 }
380 
381 static int qup_i2c_poll_state_mask(struct qup_i2c_dev *qup,
382 				   u32 req_state, u32 req_mask)
383 {
384 	int retries = 1;
385 	u32 state;
386 
387 	/*
388 	 * State transition takes 3 AHB clocks cycles + 3 I2C master clock
389 	 * cycles. So retry once after a 1uS delay.
390 	 */
391 	do {
392 		state = readl(qup->base + QUP_STATE);
393 
394 		if (state & QUP_STATE_VALID &&
395 		    (state & req_mask) == req_state)
396 			return 0;
397 
398 		udelay(1);
399 	} while (retries--);
400 
401 	return -ETIMEDOUT;
402 }
403 
404 static int qup_i2c_poll_state(struct qup_i2c_dev *qup, u32 req_state)
405 {
406 	return qup_i2c_poll_state_mask(qup, req_state, QUP_STATE_MASK);
407 }
408 
409 static void qup_i2c_flush(struct qup_i2c_dev *qup)
410 {
411 	u32 val = readl(qup->base + QUP_STATE);
412 
413 	val |= QUP_I2C_FLUSH;
414 	writel(val, qup->base + QUP_STATE);
415 }
416 
417 static int qup_i2c_poll_state_valid(struct qup_i2c_dev *qup)
418 {
419 	return qup_i2c_poll_state_mask(qup, 0, 0);
420 }
421 
422 static int qup_i2c_poll_state_i2c_master(struct qup_i2c_dev *qup)
423 {
424 	return qup_i2c_poll_state_mask(qup, QUP_I2C_MAST_GEN, QUP_I2C_MAST_GEN);
425 }
426 
427 static int qup_i2c_change_state(struct qup_i2c_dev *qup, u32 state)
428 {
429 	if (qup_i2c_poll_state_valid(qup) != 0)
430 		return -EIO;
431 
432 	writel(state, qup->base + QUP_STATE);
433 
434 	if (qup_i2c_poll_state(qup, state) != 0)
435 		return -EIO;
436 	return 0;
437 }
438 
439 /* Check if I2C bus returns to IDLE state */
440 static int qup_i2c_bus_active(struct qup_i2c_dev *qup, int len)
441 {
442 	unsigned long timeout;
443 	u32 status;
444 	int ret = 0;
445 
446 	timeout = jiffies + len * 4;
447 	for (;;) {
448 		status = readl(qup->base + QUP_I2C_STATUS);
449 		if (!(status & I2C_STATUS_BUS_ACTIVE))
450 			break;
451 
452 		if (time_after(jiffies, timeout))
453 			ret = -ETIMEDOUT;
454 
455 		usleep_range(len, len * 2);
456 	}
457 
458 	return ret;
459 }
460 
461 static void qup_i2c_write_tx_fifo_v1(struct qup_i2c_dev *qup)
462 {
463 	struct qup_i2c_block *blk = &qup->blk;
464 	struct i2c_msg *msg = qup->msg;
465 	u32 addr = i2c_8bit_addr_from_msg(msg);
466 	u32 qup_tag;
467 	int idx;
468 	u32 val;
469 
470 	if (qup->pos == 0) {
471 		val = QUP_TAG_START | addr;
472 		idx = 1;
473 		blk->tx_fifo_free--;
474 	} else {
475 		val = 0;
476 		idx = 0;
477 	}
478 
479 	while (blk->tx_fifo_free && qup->pos < msg->len) {
480 		if (qup->pos == msg->len - 1)
481 			qup_tag = QUP_TAG_STOP;
482 		else
483 			qup_tag = QUP_TAG_DATA;
484 
485 		if (idx & 1)
486 			val |= (qup_tag | msg->buf[qup->pos]) << QUP_MSW_SHIFT;
487 		else
488 			val = qup_tag | msg->buf[qup->pos];
489 
490 		/* Write out the pair and the last odd value */
491 		if (idx & 1 || qup->pos == msg->len - 1)
492 			writel(val, qup->base + QUP_OUT_FIFO_BASE);
493 
494 		qup->pos++;
495 		idx++;
496 		blk->tx_fifo_free--;
497 	}
498 }
499 
500 static void qup_i2c_set_blk_data(struct qup_i2c_dev *qup,
501 				 struct i2c_msg *msg)
502 {
503 	qup->blk.pos = 0;
504 	qup->blk.data_len = msg->len;
505 	qup->blk.count = DIV_ROUND_UP(msg->len, qup->blk_xfer_limit);
506 }
507 
508 static int qup_i2c_get_data_len(struct qup_i2c_dev *qup)
509 {
510 	int data_len;
511 
512 	if (qup->blk.data_len > qup->blk_xfer_limit)
513 		data_len = qup->blk_xfer_limit;
514 	else
515 		data_len = qup->blk.data_len;
516 
517 	return data_len;
518 }
519 
520 static bool qup_i2c_check_msg_len(struct i2c_msg *msg)
521 {
522 	return ((msg->flags & I2C_M_RD) && (msg->flags & I2C_M_RECV_LEN));
523 }
524 
525 static int qup_i2c_set_tags_smb(u16 addr, u8 *tags, struct qup_i2c_dev *qup,
526 			struct i2c_msg *msg)
527 {
528 	int len = 0;
529 
530 	if (qup->is_smbus_read) {
531 		tags[len++] = QUP_TAG_V2_DATARD_STOP;
532 		tags[len++] = qup_i2c_get_data_len(qup);
533 	} else {
534 		tags[len++] = QUP_TAG_V2_START;
535 		tags[len++] = addr & 0xff;
536 
537 		if (msg->flags & I2C_M_TEN)
538 			tags[len++] = addr >> 8;
539 
540 		tags[len++] = QUP_TAG_V2_DATARD;
541 		/* Read 1 byte indicating the length of the SMBus message */
542 		tags[len++] = 1;
543 	}
544 	return len;
545 }
546 
547 static int qup_i2c_set_tags(u8 *tags, struct qup_i2c_dev *qup,
548 			    struct i2c_msg *msg)
549 {
550 	u16 addr = i2c_8bit_addr_from_msg(msg);
551 	int len = 0;
552 	int data_len;
553 
554 	int last = (qup->blk.pos == (qup->blk.count - 1)) && (qup->is_last);
555 
556 	/* Handle tags for SMBus block read */
557 	if (qup_i2c_check_msg_len(msg))
558 		return qup_i2c_set_tags_smb(addr, tags, qup, msg);
559 
560 	if (qup->blk.pos == 0) {
561 		tags[len++] = QUP_TAG_V2_START;
562 		tags[len++] = addr & 0xff;
563 
564 		if (msg->flags & I2C_M_TEN)
565 			tags[len++] = addr >> 8;
566 	}
567 
568 	/* Send _STOP commands for the last block */
569 	if (last) {
570 		if (msg->flags & I2C_M_RD)
571 			tags[len++] = QUP_TAG_V2_DATARD_STOP;
572 		else
573 			tags[len++] = QUP_TAG_V2_DATAWR_STOP;
574 	} else {
575 		if (msg->flags & I2C_M_RD)
576 			tags[len++] = qup->blk.pos == (qup->blk.count - 1) ?
577 				      QUP_TAG_V2_DATARD_NACK :
578 				      QUP_TAG_V2_DATARD;
579 		else
580 			tags[len++] = QUP_TAG_V2_DATAWR;
581 	}
582 
583 	data_len = qup_i2c_get_data_len(qup);
584 
585 	/* 0 implies 256 bytes */
586 	if (data_len == QUP_READ_LIMIT)
587 		tags[len++] = 0;
588 	else
589 		tags[len++] = data_len;
590 
591 	return len;
592 }
593 
594 
595 static void qup_i2c_bam_cb(void *data)
596 {
597 	struct qup_i2c_dev *qup = data;
598 
599 	complete(&qup->xfer);
600 }
601 
602 static int qup_sg_set_buf(struct scatterlist *sg, void *buf,
603 			  unsigned int buflen, struct qup_i2c_dev *qup,
604 			  int dir)
605 {
606 	int ret;
607 
608 	sg_set_buf(sg, buf, buflen);
609 	ret = dma_map_sg(qup->dev, sg, 1, dir);
610 	if (!ret)
611 		return -EINVAL;
612 
613 	return 0;
614 }
615 
616 static void qup_i2c_rel_dma(struct qup_i2c_dev *qup)
617 {
618 	if (qup->btx.dma)
619 		dma_release_channel(qup->btx.dma);
620 	if (qup->brx.dma)
621 		dma_release_channel(qup->brx.dma);
622 	qup->btx.dma = NULL;
623 	qup->brx.dma = NULL;
624 }
625 
626 static int qup_i2c_req_dma(struct qup_i2c_dev *qup)
627 {
628 	int err;
629 
630 	if (!qup->btx.dma) {
631 		qup->btx.dma = dma_request_slave_channel_reason(qup->dev, "tx");
632 		if (IS_ERR(qup->btx.dma)) {
633 			err = PTR_ERR(qup->btx.dma);
634 			qup->btx.dma = NULL;
635 			dev_err(qup->dev, "\n tx channel not available");
636 			return err;
637 		}
638 	}
639 
640 	if (!qup->brx.dma) {
641 		qup->brx.dma = dma_request_slave_channel_reason(qup->dev, "rx");
642 		if (IS_ERR(qup->brx.dma)) {
643 			dev_err(qup->dev, "\n rx channel not available");
644 			err = PTR_ERR(qup->brx.dma);
645 			qup->brx.dma = NULL;
646 			qup_i2c_rel_dma(qup);
647 			return err;
648 		}
649 	}
650 	return 0;
651 }
652 
653 static int qup_i2c_bam_make_desc(struct qup_i2c_dev *qup, struct i2c_msg *msg)
654 {
655 	int ret = 0, limit = QUP_READ_LIMIT;
656 	u32 len = 0, blocks, rem;
657 	u32 i = 0, tlen, tx_len = 0;
658 	u8 *tags;
659 
660 	qup->blk_xfer_limit = QUP_READ_LIMIT;
661 	qup_i2c_set_blk_data(qup, msg);
662 
663 	blocks = qup->blk.count;
664 	rem = msg->len - (blocks - 1) * limit;
665 
666 	if (msg->flags & I2C_M_RD) {
667 		while (qup->blk.pos < blocks) {
668 			tlen = (i == (blocks - 1)) ? rem : limit;
669 			tags = &qup->start_tag.start[qup->tag_buf_pos + len];
670 			len += qup_i2c_set_tags(tags, qup, msg);
671 			qup->blk.data_len -= tlen;
672 
673 			/* scratch buf to read the start and len tags */
674 			ret = qup_sg_set_buf(&qup->brx.sg[qup->brx.sg_cnt++],
675 					     &qup->brx.tag.start[0],
676 					     2, qup, DMA_FROM_DEVICE);
677 
678 			if (ret)
679 				return ret;
680 
681 			ret = qup_sg_set_buf(&qup->brx.sg[qup->brx.sg_cnt++],
682 					     &msg->buf[limit * i],
683 					     tlen, qup,
684 					     DMA_FROM_DEVICE);
685 			if (ret)
686 				return ret;
687 
688 			i++;
689 			qup->blk.pos = i;
690 		}
691 		ret = qup_sg_set_buf(&qup->btx.sg[qup->btx.sg_cnt++],
692 				     &qup->start_tag.start[qup->tag_buf_pos],
693 				     len, qup, DMA_TO_DEVICE);
694 		if (ret)
695 			return ret;
696 
697 		qup->tag_buf_pos += len;
698 	} else {
699 		while (qup->blk.pos < blocks) {
700 			tlen = (i == (blocks - 1)) ? rem : limit;
701 			tags = &qup->start_tag.start[qup->tag_buf_pos + tx_len];
702 			len = qup_i2c_set_tags(tags, qup, msg);
703 			qup->blk.data_len -= tlen;
704 
705 			ret = qup_sg_set_buf(&qup->btx.sg[qup->btx.sg_cnt++],
706 					     tags, len,
707 					     qup, DMA_TO_DEVICE);
708 			if (ret)
709 				return ret;
710 
711 			tx_len += len;
712 			ret = qup_sg_set_buf(&qup->btx.sg[qup->btx.sg_cnt++],
713 					     &msg->buf[limit * i],
714 					     tlen, qup, DMA_TO_DEVICE);
715 			if (ret)
716 				return ret;
717 			i++;
718 			qup->blk.pos = i;
719 		}
720 
721 		qup->tag_buf_pos += tx_len;
722 	}
723 
724 	return 0;
725 }
726 
727 static int qup_i2c_bam_schedule_desc(struct qup_i2c_dev *qup)
728 {
729 	struct dma_async_tx_descriptor *txd, *rxd = NULL;
730 	int ret = 0;
731 	dma_cookie_t cookie_rx, cookie_tx;
732 	u32 len = 0;
733 	u32 tx_cnt = qup->btx.sg_cnt, rx_cnt = qup->brx.sg_cnt;
734 
735 	/* schedule the EOT and FLUSH I2C tags */
736 	len = 1;
737 	if (rx_cnt) {
738 		qup->btx.tag.start[0] = QUP_BAM_INPUT_EOT;
739 		len++;
740 
741 		/* scratch buf to read the BAM EOT FLUSH tags */
742 		ret = qup_sg_set_buf(&qup->brx.sg[rx_cnt++],
743 				     &qup->brx.tag.start[0],
744 				     1, qup, DMA_FROM_DEVICE);
745 		if (ret)
746 			return ret;
747 	}
748 
749 	qup->btx.tag.start[len - 1] = QUP_BAM_FLUSH_STOP;
750 	ret = qup_sg_set_buf(&qup->btx.sg[tx_cnt++], &qup->btx.tag.start[0],
751 			     len, qup, DMA_TO_DEVICE);
752 	if (ret)
753 		return ret;
754 
755 	txd = dmaengine_prep_slave_sg(qup->btx.dma, qup->btx.sg, tx_cnt,
756 				      DMA_MEM_TO_DEV,
757 				      DMA_PREP_INTERRUPT | DMA_PREP_FENCE);
758 	if (!txd) {
759 		dev_err(qup->dev, "failed to get tx desc\n");
760 		ret = -EINVAL;
761 		goto desc_err;
762 	}
763 
764 	if (!rx_cnt) {
765 		txd->callback = qup_i2c_bam_cb;
766 		txd->callback_param = qup;
767 	}
768 
769 	cookie_tx = dmaengine_submit(txd);
770 	if (dma_submit_error(cookie_tx)) {
771 		ret = -EINVAL;
772 		goto desc_err;
773 	}
774 
775 	dma_async_issue_pending(qup->btx.dma);
776 
777 	if (rx_cnt) {
778 		rxd = dmaengine_prep_slave_sg(qup->brx.dma, qup->brx.sg,
779 					      rx_cnt, DMA_DEV_TO_MEM,
780 					      DMA_PREP_INTERRUPT);
781 		if (!rxd) {
782 			dev_err(qup->dev, "failed to get rx desc\n");
783 			ret = -EINVAL;
784 
785 			/* abort TX descriptors */
786 			dmaengine_terminate_all(qup->btx.dma);
787 			goto desc_err;
788 		}
789 
790 		rxd->callback = qup_i2c_bam_cb;
791 		rxd->callback_param = qup;
792 		cookie_rx = dmaengine_submit(rxd);
793 		if (dma_submit_error(cookie_rx)) {
794 			ret = -EINVAL;
795 			goto desc_err;
796 		}
797 
798 		dma_async_issue_pending(qup->brx.dma);
799 	}
800 
801 	if (!wait_for_completion_timeout(&qup->xfer, qup->xfer_timeout)) {
802 		dev_err(qup->dev, "normal trans timed out\n");
803 		ret = -ETIMEDOUT;
804 	}
805 
806 	if (ret || qup->bus_err || qup->qup_err) {
807 		reinit_completion(&qup->xfer);
808 
809 		if (qup_i2c_change_state(qup, QUP_RUN_STATE)) {
810 			dev_err(qup->dev, "change to run state timed out");
811 			goto desc_err;
812 		}
813 
814 		qup_i2c_flush(qup);
815 
816 		/* wait for remaining interrupts to occur */
817 		if (!wait_for_completion_timeout(&qup->xfer, HZ))
818 			dev_err(qup->dev, "flush timed out\n");
819 
820 		ret =  (qup->bus_err & QUP_I2C_NACK_FLAG) ? -ENXIO : -EIO;
821 	}
822 
823 desc_err:
824 	dma_unmap_sg(qup->dev, qup->btx.sg, tx_cnt, DMA_TO_DEVICE);
825 
826 	if (rx_cnt)
827 		dma_unmap_sg(qup->dev, qup->brx.sg, rx_cnt,
828 			     DMA_FROM_DEVICE);
829 
830 	return ret;
831 }
832 
833 static void qup_i2c_bam_clear_tag_buffers(struct qup_i2c_dev *qup)
834 {
835 	qup->btx.sg_cnt = 0;
836 	qup->brx.sg_cnt = 0;
837 	qup->tag_buf_pos = 0;
838 }
839 
840 static int qup_i2c_bam_xfer(struct i2c_adapter *adap, struct i2c_msg *msg,
841 			    int num)
842 {
843 	struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
844 	int ret = 0;
845 	int idx = 0;
846 
847 	enable_irq(qup->irq);
848 	ret = qup_i2c_req_dma(qup);
849 
850 	if (ret)
851 		goto out;
852 
853 	writel(0, qup->base + QUP_MX_INPUT_CNT);
854 	writel(0, qup->base + QUP_MX_OUTPUT_CNT);
855 
856 	/* set BAM mode */
857 	writel(QUP_REPACK_EN | QUP_BAM_MODE, qup->base + QUP_IO_MODE);
858 
859 	/* mask fifo irqs */
860 	writel((0x3 << 8), qup->base + QUP_OPERATIONAL_MASK);
861 
862 	/* set RUN STATE */
863 	ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
864 	if (ret)
865 		goto out;
866 
867 	writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
868 	qup_i2c_bam_clear_tag_buffers(qup);
869 
870 	for (idx = 0; idx < num; idx++) {
871 		qup->msg = msg + idx;
872 		qup->is_last = idx == (num - 1);
873 
874 		ret = qup_i2c_bam_make_desc(qup, qup->msg);
875 		if (ret)
876 			break;
877 
878 		/*
879 		 * Make DMA descriptor and schedule the BAM transfer if its
880 		 * already crossed the maximum length. Since the memory for all
881 		 * tags buffers have been taken for 2 maximum possible
882 		 * transfers length so it will never cross the buffer actual
883 		 * length.
884 		 */
885 		if (qup->btx.sg_cnt > qup->max_xfer_sg_len ||
886 		    qup->brx.sg_cnt > qup->max_xfer_sg_len ||
887 		    qup->is_last) {
888 			ret = qup_i2c_bam_schedule_desc(qup);
889 			if (ret)
890 				break;
891 
892 			qup_i2c_bam_clear_tag_buffers(qup);
893 		}
894 	}
895 
896 out:
897 	disable_irq(qup->irq);
898 
899 	qup->msg = NULL;
900 	return ret;
901 }
902 
903 static int qup_i2c_wait_for_complete(struct qup_i2c_dev *qup,
904 				     struct i2c_msg *msg)
905 {
906 	unsigned long left;
907 	int ret = 0;
908 
909 	left = wait_for_completion_timeout(&qup->xfer, qup->xfer_timeout);
910 	if (!left) {
911 		writel(1, qup->base + QUP_SW_RESET);
912 		ret = -ETIMEDOUT;
913 	}
914 
915 	if (qup->bus_err || qup->qup_err)
916 		ret =  (qup->bus_err & QUP_I2C_NACK_FLAG) ? -ENXIO : -EIO;
917 
918 	return ret;
919 }
920 
921 static void qup_i2c_read_rx_fifo_v1(struct qup_i2c_dev *qup)
922 {
923 	struct qup_i2c_block *blk = &qup->blk;
924 	struct i2c_msg *msg = qup->msg;
925 	u32 val = 0;
926 	int idx = 0;
927 
928 	while (blk->fifo_available && qup->pos < msg->len) {
929 		if ((idx & 1) == 0) {
930 			/* Reading 2 words at time */
931 			val = readl(qup->base + QUP_IN_FIFO_BASE);
932 			msg->buf[qup->pos++] = val & 0xFF;
933 		} else {
934 			msg->buf[qup->pos++] = val >> QUP_MSW_SHIFT;
935 		}
936 		idx++;
937 		blk->fifo_available--;
938 	}
939 
940 	if (qup->pos == msg->len)
941 		blk->rx_bytes_read = true;
942 }
943 
944 static void qup_i2c_write_rx_tags_v1(struct qup_i2c_dev *qup)
945 {
946 	struct i2c_msg *msg = qup->msg;
947 	u32 addr, len, val;
948 
949 	addr = i2c_8bit_addr_from_msg(msg);
950 
951 	/* 0 is used to specify a length 256 (QUP_READ_LIMIT) */
952 	len = (msg->len == QUP_READ_LIMIT) ? 0 : msg->len;
953 
954 	val = ((QUP_TAG_REC | len) << QUP_MSW_SHIFT) | QUP_TAG_START | addr;
955 	writel(val, qup->base + QUP_OUT_FIFO_BASE);
956 }
957 
958 static void qup_i2c_conf_v1(struct qup_i2c_dev *qup)
959 {
960 	struct qup_i2c_block *blk = &qup->blk;
961 	u32 qup_config = I2C_MINI_CORE | I2C_N_VAL;
962 	u32 io_mode = QUP_REPACK_EN;
963 
964 	blk->is_tx_blk_mode =
965 		blk->total_tx_len > qup->out_fifo_sz ? true : false;
966 	blk->is_rx_blk_mode =
967 		blk->total_rx_len > qup->in_fifo_sz ? true : false;
968 
969 	if (blk->is_tx_blk_mode) {
970 		io_mode |= QUP_OUTPUT_BLK_MODE;
971 		writel(0, qup->base + QUP_MX_WRITE_CNT);
972 		writel(blk->total_tx_len, qup->base + QUP_MX_OUTPUT_CNT);
973 	} else {
974 		writel(0, qup->base + QUP_MX_OUTPUT_CNT);
975 		writel(blk->total_tx_len, qup->base + QUP_MX_WRITE_CNT);
976 	}
977 
978 	if (blk->total_rx_len) {
979 		if (blk->is_rx_blk_mode) {
980 			io_mode |= QUP_INPUT_BLK_MODE;
981 			writel(0, qup->base + QUP_MX_READ_CNT);
982 			writel(blk->total_rx_len, qup->base + QUP_MX_INPUT_CNT);
983 		} else {
984 			writel(0, qup->base + QUP_MX_INPUT_CNT);
985 			writel(blk->total_rx_len, qup->base + QUP_MX_READ_CNT);
986 		}
987 	} else {
988 		qup_config |= QUP_NO_INPUT;
989 	}
990 
991 	writel(qup_config, qup->base + QUP_CONFIG);
992 	writel(io_mode, qup->base + QUP_IO_MODE);
993 }
994 
995 static void qup_i2c_clear_blk_v1(struct qup_i2c_block *blk)
996 {
997 	blk->tx_fifo_free = 0;
998 	blk->fifo_available = 0;
999 	blk->rx_bytes_read = false;
1000 }
1001 
1002 static int qup_i2c_conf_xfer_v1(struct qup_i2c_dev *qup, bool is_rx)
1003 {
1004 	struct qup_i2c_block *blk = &qup->blk;
1005 	int ret;
1006 
1007 	qup_i2c_clear_blk_v1(blk);
1008 	qup_i2c_conf_v1(qup);
1009 	ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
1010 	if (ret)
1011 		return ret;
1012 
1013 	writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
1014 
1015 	ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
1016 	if (ret)
1017 		return ret;
1018 
1019 	reinit_completion(&qup->xfer);
1020 	enable_irq(qup->irq);
1021 	if (!blk->is_tx_blk_mode) {
1022 		blk->tx_fifo_free = qup->out_fifo_sz;
1023 
1024 		if (is_rx)
1025 			qup_i2c_write_rx_tags_v1(qup);
1026 		else
1027 			qup_i2c_write_tx_fifo_v1(qup);
1028 	}
1029 
1030 	ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
1031 	if (ret)
1032 		goto err;
1033 
1034 	ret = qup_i2c_wait_for_complete(qup, qup->msg);
1035 	if (ret)
1036 		goto err;
1037 
1038 	ret = qup_i2c_bus_active(qup, ONE_BYTE);
1039 
1040 err:
1041 	disable_irq(qup->irq);
1042 	return ret;
1043 }
1044 
1045 static int qup_i2c_write_one(struct qup_i2c_dev *qup)
1046 {
1047 	struct i2c_msg *msg = qup->msg;
1048 	struct qup_i2c_block *blk = &qup->blk;
1049 
1050 	qup->pos = 0;
1051 	blk->total_tx_len = msg->len + 1;
1052 	blk->total_rx_len = 0;
1053 
1054 	return qup_i2c_conf_xfer_v1(qup, false);
1055 }
1056 
1057 static int qup_i2c_read_one(struct qup_i2c_dev *qup)
1058 {
1059 	struct qup_i2c_block *blk = &qup->blk;
1060 
1061 	qup->pos = 0;
1062 	blk->total_tx_len = 2;
1063 	blk->total_rx_len = qup->msg->len;
1064 
1065 	return qup_i2c_conf_xfer_v1(qup, true);
1066 }
1067 
1068 static int qup_i2c_xfer(struct i2c_adapter *adap,
1069 			struct i2c_msg msgs[],
1070 			int num)
1071 {
1072 	struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
1073 	int ret, idx;
1074 
1075 	ret = pm_runtime_get_sync(qup->dev);
1076 	if (ret < 0)
1077 		goto out;
1078 
1079 	qup->bus_err = 0;
1080 	qup->qup_err = 0;
1081 
1082 	writel(1, qup->base + QUP_SW_RESET);
1083 	ret = qup_i2c_poll_state(qup, QUP_RESET_STATE);
1084 	if (ret)
1085 		goto out;
1086 
1087 	/* Configure QUP as I2C mini core */
1088 	writel(I2C_MINI_CORE | I2C_N_VAL, qup->base + QUP_CONFIG);
1089 
1090 	for (idx = 0; idx < num; idx++) {
1091 		if (qup_i2c_poll_state_i2c_master(qup)) {
1092 			ret = -EIO;
1093 			goto out;
1094 		}
1095 
1096 		if (qup_i2c_check_msg_len(&msgs[idx])) {
1097 			ret = -EINVAL;
1098 			goto out;
1099 		}
1100 
1101 		qup->msg = &msgs[idx];
1102 		if (msgs[idx].flags & I2C_M_RD)
1103 			ret = qup_i2c_read_one(qup);
1104 		else
1105 			ret = qup_i2c_write_one(qup);
1106 
1107 		if (ret)
1108 			break;
1109 
1110 		ret = qup_i2c_change_state(qup, QUP_RESET_STATE);
1111 		if (ret)
1112 			break;
1113 	}
1114 
1115 	if (ret == 0)
1116 		ret = num;
1117 out:
1118 
1119 	pm_runtime_mark_last_busy(qup->dev);
1120 	pm_runtime_put_autosuspend(qup->dev);
1121 
1122 	return ret;
1123 }
1124 
1125 /*
1126  * Configure registers related with reconfiguration during run and call it
1127  * before each i2c sub transfer.
1128  */
1129 static void qup_i2c_conf_count_v2(struct qup_i2c_dev *qup)
1130 {
1131 	struct qup_i2c_block *blk = &qup->blk;
1132 	u32 qup_config = I2C_MINI_CORE | I2C_N_VAL_V2;
1133 
1134 	if (blk->is_tx_blk_mode)
1135 		writel(qup->config_run | blk->total_tx_len,
1136 		       qup->base + QUP_MX_OUTPUT_CNT);
1137 	else
1138 		writel(qup->config_run | blk->total_tx_len,
1139 		       qup->base + QUP_MX_WRITE_CNT);
1140 
1141 	if (blk->total_rx_len) {
1142 		if (blk->is_rx_blk_mode)
1143 			writel(qup->config_run | blk->total_rx_len,
1144 			       qup->base + QUP_MX_INPUT_CNT);
1145 		else
1146 			writel(qup->config_run | blk->total_rx_len,
1147 			       qup->base + QUP_MX_READ_CNT);
1148 	} else {
1149 		qup_config |= QUP_NO_INPUT;
1150 	}
1151 
1152 	writel(qup_config, qup->base + QUP_CONFIG);
1153 }
1154 
1155 /*
1156  * Configure registers related with transfer mode (FIFO/Block)
1157  * before starting of i2c transfer. It will be called only once in
1158  * QUP RESET state.
1159  */
1160 static void qup_i2c_conf_mode_v2(struct qup_i2c_dev *qup)
1161 {
1162 	struct qup_i2c_block *blk = &qup->blk;
1163 	u32 io_mode = QUP_REPACK_EN;
1164 
1165 	if (blk->is_tx_blk_mode) {
1166 		io_mode |= QUP_OUTPUT_BLK_MODE;
1167 		writel(0, qup->base + QUP_MX_WRITE_CNT);
1168 	} else {
1169 		writel(0, qup->base + QUP_MX_OUTPUT_CNT);
1170 	}
1171 
1172 	if (blk->is_rx_blk_mode) {
1173 		io_mode |= QUP_INPUT_BLK_MODE;
1174 		writel(0, qup->base + QUP_MX_READ_CNT);
1175 	} else {
1176 		writel(0, qup->base + QUP_MX_INPUT_CNT);
1177 	}
1178 
1179 	writel(io_mode, qup->base + QUP_IO_MODE);
1180 }
1181 
1182 /* Clear required variables before starting of any QUP v2 sub transfer. */
1183 static void qup_i2c_clear_blk_v2(struct qup_i2c_block *blk)
1184 {
1185 	blk->send_last_word = false;
1186 	blk->tx_tags_sent = false;
1187 	blk->tx_fifo_data = 0;
1188 	blk->tx_fifo_data_pos = 0;
1189 	blk->tx_fifo_free = 0;
1190 
1191 	blk->rx_tags_fetched = false;
1192 	blk->rx_bytes_read = false;
1193 	blk->rx_fifo_data = 0;
1194 	blk->rx_fifo_data_pos = 0;
1195 	blk->fifo_available = 0;
1196 }
1197 
1198 /* Receive data from RX FIFO for read message in QUP v2 i2c transfer. */
1199 static void qup_i2c_recv_data(struct qup_i2c_dev *qup)
1200 {
1201 	struct qup_i2c_block *blk = &qup->blk;
1202 	int j;
1203 
1204 	for (j = blk->rx_fifo_data_pos;
1205 	     blk->cur_blk_len && blk->fifo_available;
1206 	     blk->cur_blk_len--, blk->fifo_available--) {
1207 		if (j == 0)
1208 			blk->rx_fifo_data = readl(qup->base + QUP_IN_FIFO_BASE);
1209 
1210 		*(blk->cur_data++) = blk->rx_fifo_data;
1211 		blk->rx_fifo_data >>= 8;
1212 
1213 		if (j == 3)
1214 			j = 0;
1215 		else
1216 			j++;
1217 	}
1218 
1219 	blk->rx_fifo_data_pos = j;
1220 }
1221 
1222 /* Receive tags for read message in QUP v2 i2c transfer. */
1223 static void qup_i2c_recv_tags(struct qup_i2c_dev *qup)
1224 {
1225 	struct qup_i2c_block *blk = &qup->blk;
1226 
1227 	blk->rx_fifo_data = readl(qup->base + QUP_IN_FIFO_BASE);
1228 	blk->rx_fifo_data >>= blk->rx_tag_len  * 8;
1229 	blk->rx_fifo_data_pos = blk->rx_tag_len;
1230 	blk->fifo_available -= blk->rx_tag_len;
1231 }
1232 
1233 /*
1234  * Read the data and tags from RX FIFO. Since in read case, the tags will be
1235  * preceded by received data bytes so
1236  * 1. Check if rx_tags_fetched is false i.e. the start of QUP block so receive
1237  *    all tag bytes and discard that.
1238  * 2. Read the data from RX FIFO. When all the data bytes have been read then
1239  *    set rx_bytes_read to true.
1240  */
1241 static void qup_i2c_read_rx_fifo_v2(struct qup_i2c_dev *qup)
1242 {
1243 	struct qup_i2c_block *blk = &qup->blk;
1244 
1245 	if (!blk->rx_tags_fetched) {
1246 		qup_i2c_recv_tags(qup);
1247 		blk->rx_tags_fetched = true;
1248 	}
1249 
1250 	qup_i2c_recv_data(qup);
1251 	if (!blk->cur_blk_len)
1252 		blk->rx_bytes_read = true;
1253 }
1254 
1255 /*
1256  * Write bytes in TX FIFO for write message in QUP v2 i2c transfer. QUP TX FIFO
1257  * write works on word basis (4 bytes). Append new data byte write for TX FIFO
1258  * in tx_fifo_data and write to TX FIFO when all the 4 bytes are present.
1259  */
1260 static void
1261 qup_i2c_write_blk_data(struct qup_i2c_dev *qup, u8 **data, unsigned int *len)
1262 {
1263 	struct qup_i2c_block *blk = &qup->blk;
1264 	unsigned int j;
1265 
1266 	for (j = blk->tx_fifo_data_pos; *len && blk->tx_fifo_free;
1267 	     (*len)--, blk->tx_fifo_free--) {
1268 		blk->tx_fifo_data |= *(*data)++ << (j * 8);
1269 		if (j == 3) {
1270 			writel(blk->tx_fifo_data,
1271 			       qup->base + QUP_OUT_FIFO_BASE);
1272 			blk->tx_fifo_data = 0x0;
1273 			j = 0;
1274 		} else {
1275 			j++;
1276 		}
1277 	}
1278 
1279 	blk->tx_fifo_data_pos = j;
1280 }
1281 
1282 /* Transfer tags for read message in QUP v2 i2c transfer. */
1283 static void qup_i2c_write_rx_tags_v2(struct qup_i2c_dev *qup)
1284 {
1285 	struct qup_i2c_block *blk = &qup->blk;
1286 
1287 	qup_i2c_write_blk_data(qup, &blk->cur_tx_tags, &blk->tx_tag_len);
1288 	if (blk->tx_fifo_data_pos)
1289 		writel(blk->tx_fifo_data, qup->base + QUP_OUT_FIFO_BASE);
1290 }
1291 
1292 /*
1293  * Write the data and tags in TX FIFO. Since in write case, both tags and data
1294  * need to be written and QUP write tags can have maximum 256 data length, so
1295  *
1296  * 1. Check if tx_tags_sent is false i.e. the start of QUP block so write the
1297  *    tags to TX FIFO and set tx_tags_sent to true.
1298  * 2. Check if send_last_word is true. It will be set when last few data bytes
1299  *    (less than 4 bytes) are reamining to be written in FIFO because of no FIFO
1300  *    space. All this data bytes are available in tx_fifo_data so write this
1301  *    in FIFO.
1302  * 3. Write the data to TX FIFO and check for cur_blk_len. If it is non zero
1303  *    then more data is pending otherwise following 3 cases can be possible
1304  *    a. if tx_fifo_data_pos is zero i.e. all the data bytes in this block
1305  *       have been written in TX FIFO so nothing else is required.
1306  *    b. tx_fifo_free is non zero i.e tx FIFO is free so copy the remaining data
1307  *       from tx_fifo_data to tx FIFO. Since, qup_i2c_write_blk_data do write
1308  *	 in 4 bytes and FIFO space is in multiple of 4 bytes so tx_fifo_free
1309  *       will be always greater than or equal to 4 bytes.
1310  *    c. tx_fifo_free is zero. In this case, last few bytes (less than 4
1311  *       bytes) are copied to tx_fifo_data but couldn't be sent because of
1312  *       FIFO full so make send_last_word true.
1313  */
1314 static void qup_i2c_write_tx_fifo_v2(struct qup_i2c_dev *qup)
1315 {
1316 	struct qup_i2c_block *blk = &qup->blk;
1317 
1318 	if (!blk->tx_tags_sent) {
1319 		qup_i2c_write_blk_data(qup, &blk->cur_tx_tags,
1320 				       &blk->tx_tag_len);
1321 		blk->tx_tags_sent = true;
1322 	}
1323 
1324 	if (blk->send_last_word)
1325 		goto send_last_word;
1326 
1327 	qup_i2c_write_blk_data(qup, &blk->cur_data, &blk->cur_blk_len);
1328 	if (!blk->cur_blk_len) {
1329 		if (!blk->tx_fifo_data_pos)
1330 			return;
1331 
1332 		if (blk->tx_fifo_free)
1333 			goto send_last_word;
1334 
1335 		blk->send_last_word = true;
1336 	}
1337 
1338 	return;
1339 
1340 send_last_word:
1341 	writel(blk->tx_fifo_data, qup->base + QUP_OUT_FIFO_BASE);
1342 }
1343 
1344 /*
1345  * Main transfer function which read or write i2c data.
1346  * The QUP v2 supports reconfiguration during run in which multiple i2c sub
1347  * transfers can be scheduled.
1348  */
1349 static int
1350 qup_i2c_conf_xfer_v2(struct qup_i2c_dev *qup, bool is_rx, bool is_first,
1351 		     bool change_pause_state)
1352 {
1353 	struct qup_i2c_block *blk = &qup->blk;
1354 	struct i2c_msg *msg = qup->msg;
1355 	int ret;
1356 
1357 	/*
1358 	 * Check if its SMBus Block read for which the top level read will be
1359 	 * done into 2 QUP reads. One with message length 1 while other one is
1360 	 * with actual length.
1361 	 */
1362 	if (qup_i2c_check_msg_len(msg)) {
1363 		if (qup->is_smbus_read) {
1364 			/*
1365 			 * If the message length is already read in
1366 			 * the first byte of the buffer, account for
1367 			 * that by setting the offset
1368 			 */
1369 			blk->cur_data += 1;
1370 			is_first = false;
1371 		} else {
1372 			change_pause_state = false;
1373 		}
1374 	}
1375 
1376 	qup->config_run = is_first ? 0 : QUP_I2C_MX_CONFIG_DURING_RUN;
1377 
1378 	qup_i2c_clear_blk_v2(blk);
1379 	qup_i2c_conf_count_v2(qup);
1380 
1381 	/* If it is first sub transfer, then configure i2c bus clocks */
1382 	if (is_first) {
1383 		ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
1384 		if (ret)
1385 			return ret;
1386 
1387 		writel(qup->clk_ctl, qup->base + QUP_I2C_CLK_CTL);
1388 
1389 		ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
1390 		if (ret)
1391 			return ret;
1392 	}
1393 
1394 	reinit_completion(&qup->xfer);
1395 	enable_irq(qup->irq);
1396 	/*
1397 	 * In FIFO mode, tx FIFO can be written directly while in block mode the
1398 	 * it will be written after getting OUT_BLOCK_WRITE_REQ interrupt
1399 	 */
1400 	if (!blk->is_tx_blk_mode) {
1401 		blk->tx_fifo_free = qup->out_fifo_sz;
1402 
1403 		if (is_rx)
1404 			qup_i2c_write_rx_tags_v2(qup);
1405 		else
1406 			qup_i2c_write_tx_fifo_v2(qup);
1407 	}
1408 
1409 	ret = qup_i2c_change_state(qup, QUP_RUN_STATE);
1410 	if (ret)
1411 		goto err;
1412 
1413 	ret = qup_i2c_wait_for_complete(qup, msg);
1414 	if (ret)
1415 		goto err;
1416 
1417 	/* Move to pause state for all the transfers, except last one */
1418 	if (change_pause_state) {
1419 		ret = qup_i2c_change_state(qup, QUP_PAUSE_STATE);
1420 		if (ret)
1421 			goto err;
1422 	}
1423 
1424 err:
1425 	disable_irq(qup->irq);
1426 	return ret;
1427 }
1428 
1429 /*
1430  * Transfer one read/write message in i2c transfer. It splits the message into
1431  * multiple of blk_xfer_limit data length blocks and schedule each
1432  * QUP block individually.
1433  */
1434 static int qup_i2c_xfer_v2_msg(struct qup_i2c_dev *qup, int msg_id, bool is_rx)
1435 {
1436 	int ret = 0;
1437 	unsigned int data_len, i;
1438 	struct i2c_msg *msg = qup->msg;
1439 	struct qup_i2c_block *blk = &qup->blk;
1440 	u8 *msg_buf = msg->buf;
1441 
1442 	qup->blk_xfer_limit = is_rx ? RECV_MAX_DATA_LEN : QUP_READ_LIMIT;
1443 	qup_i2c_set_blk_data(qup, msg);
1444 
1445 	for (i = 0; i < blk->count; i++) {
1446 		data_len =  qup_i2c_get_data_len(qup);
1447 		blk->pos = i;
1448 		blk->cur_tx_tags = blk->tags;
1449 		blk->cur_blk_len = data_len;
1450 		blk->tx_tag_len =
1451 			qup_i2c_set_tags(blk->cur_tx_tags, qup, qup->msg);
1452 
1453 		blk->cur_data = msg_buf;
1454 
1455 		if (is_rx) {
1456 			blk->total_tx_len = blk->tx_tag_len;
1457 			blk->rx_tag_len = 2;
1458 			blk->total_rx_len = blk->rx_tag_len + data_len;
1459 		} else {
1460 			blk->total_tx_len = blk->tx_tag_len + data_len;
1461 			blk->total_rx_len = 0;
1462 		}
1463 
1464 		ret = qup_i2c_conf_xfer_v2(qup, is_rx, !msg_id && !i,
1465 					   !qup->is_last || i < blk->count - 1);
1466 		if (ret)
1467 			return ret;
1468 
1469 		/* Handle SMBus block read length */
1470 		if (qup_i2c_check_msg_len(msg) && msg->len == 1 &&
1471 		    !qup->is_smbus_read) {
1472 			if (msg->buf[0] > I2C_SMBUS_BLOCK_MAX)
1473 				return -EPROTO;
1474 
1475 			msg->len = msg->buf[0];
1476 			qup->is_smbus_read = true;
1477 			ret = qup_i2c_xfer_v2_msg(qup, msg_id, true);
1478 			qup->is_smbus_read = false;
1479 			if (ret)
1480 				return ret;
1481 
1482 			msg->len += 1;
1483 		}
1484 
1485 		msg_buf += data_len;
1486 		blk->data_len -= qup->blk_xfer_limit;
1487 	}
1488 
1489 	return ret;
1490 }
1491 
1492 /*
1493  * QUP v2 supports 3 modes
1494  * Programmed IO using FIFO mode : Less than FIFO size
1495  * Programmed IO using Block mode : Greater than FIFO size
1496  * DMA using BAM : Appropriate for any transaction size but the address should
1497  *		   be DMA applicable
1498  *
1499  * This function determines the mode which will be used for this transfer. An
1500  * i2c transfer contains multiple message. Following are the rules to determine
1501  * the mode used.
1502  * 1. Determine complete length, maximum tx and rx length for complete transfer.
1503  * 2. If complete transfer length is greater than fifo size then use the DMA
1504  *    mode.
1505  * 3. In FIFO or block mode, tx and rx can operate in different mode so check
1506  *    for maximum tx and rx length to determine mode.
1507  */
1508 static int
1509 qup_i2c_determine_mode_v2(struct qup_i2c_dev *qup,
1510 			  struct i2c_msg msgs[], int num)
1511 {
1512 	int idx;
1513 	bool no_dma = false;
1514 	unsigned int max_tx_len = 0, max_rx_len = 0, total_len = 0;
1515 
1516 	/* All i2c_msgs should be transferred using either dma or cpu */
1517 	for (idx = 0; idx < num; idx++) {
1518 		if (msgs[idx].flags & I2C_M_RD)
1519 			max_rx_len = max_t(unsigned int, max_rx_len,
1520 					   msgs[idx].len);
1521 		else
1522 			max_tx_len = max_t(unsigned int, max_tx_len,
1523 					   msgs[idx].len);
1524 
1525 		if (is_vmalloc_addr(msgs[idx].buf))
1526 			no_dma = true;
1527 
1528 		total_len += msgs[idx].len;
1529 	}
1530 
1531 	if (!no_dma && qup->is_dma &&
1532 	    (total_len > qup->out_fifo_sz || total_len > qup->in_fifo_sz)) {
1533 		qup->use_dma = true;
1534 	} else {
1535 		qup->blk.is_tx_blk_mode = max_tx_len > qup->out_fifo_sz -
1536 			QUP_MAX_TAGS_LEN ? true : false;
1537 		qup->blk.is_rx_blk_mode = max_rx_len > qup->in_fifo_sz -
1538 			READ_RX_TAGS_LEN ? true : false;
1539 	}
1540 
1541 	return 0;
1542 }
1543 
1544 static int qup_i2c_xfer_v2(struct i2c_adapter *adap,
1545 			   struct i2c_msg msgs[],
1546 			   int num)
1547 {
1548 	struct qup_i2c_dev *qup = i2c_get_adapdata(adap);
1549 	int ret, idx = 0;
1550 
1551 	qup->bus_err = 0;
1552 	qup->qup_err = 0;
1553 
1554 	ret = pm_runtime_get_sync(qup->dev);
1555 	if (ret < 0)
1556 		goto out;
1557 
1558 	ret = qup_i2c_determine_mode_v2(qup, msgs, num);
1559 	if (ret)
1560 		goto out;
1561 
1562 	writel(1, qup->base + QUP_SW_RESET);
1563 	ret = qup_i2c_poll_state(qup, QUP_RESET_STATE);
1564 	if (ret)
1565 		goto out;
1566 
1567 	/* Configure QUP as I2C mini core */
1568 	writel(I2C_MINI_CORE | I2C_N_VAL_V2, qup->base + QUP_CONFIG);
1569 	writel(QUP_V2_TAGS_EN, qup->base + QUP_I2C_MASTER_GEN);
1570 
1571 	if (qup_i2c_poll_state_i2c_master(qup)) {
1572 		ret = -EIO;
1573 		goto out;
1574 	}
1575 
1576 	if (qup->use_dma) {
1577 		reinit_completion(&qup->xfer);
1578 		ret = qup_i2c_bam_xfer(adap, &msgs[0], num);
1579 		qup->use_dma = false;
1580 	} else {
1581 		qup_i2c_conf_mode_v2(qup);
1582 
1583 		for (idx = 0; idx < num; idx++) {
1584 			qup->msg = &msgs[idx];
1585 			qup->is_last = idx == (num - 1);
1586 
1587 			ret = qup_i2c_xfer_v2_msg(qup, idx,
1588 					!!(msgs[idx].flags & I2C_M_RD));
1589 			if (ret)
1590 				break;
1591 		}
1592 		qup->msg = NULL;
1593 	}
1594 
1595 	if (!ret)
1596 		ret = qup_i2c_bus_active(qup, ONE_BYTE);
1597 
1598 	if (!ret)
1599 		qup_i2c_change_state(qup, QUP_RESET_STATE);
1600 
1601 	if (ret == 0)
1602 		ret = num;
1603 out:
1604 	pm_runtime_mark_last_busy(qup->dev);
1605 	pm_runtime_put_autosuspend(qup->dev);
1606 
1607 	return ret;
1608 }
1609 
1610 static u32 qup_i2c_func(struct i2c_adapter *adap)
1611 {
1612 	return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
1613 }
1614 
1615 static const struct i2c_algorithm qup_i2c_algo = {
1616 	.master_xfer	= qup_i2c_xfer,
1617 	.functionality	= qup_i2c_func,
1618 };
1619 
1620 static const struct i2c_algorithm qup_i2c_algo_v2 = {
1621 	.master_xfer	= qup_i2c_xfer_v2,
1622 	.functionality	= qup_i2c_func,
1623 };
1624 
1625 /*
1626  * The QUP block will issue a NACK and STOP on the bus when reaching
1627  * the end of the read, the length of the read is specified as one byte
1628  * which limits the possible read to 256 (QUP_READ_LIMIT) bytes.
1629  */
1630 static const struct i2c_adapter_quirks qup_i2c_quirks = {
1631 	.flags = I2C_AQ_NO_ZERO_LEN,
1632 	.max_read_len = QUP_READ_LIMIT,
1633 };
1634 
1635 static const struct i2c_adapter_quirks qup_i2c_quirks_v2 = {
1636 	.flags = I2C_AQ_NO_ZERO_LEN,
1637 };
1638 
1639 static void qup_i2c_enable_clocks(struct qup_i2c_dev *qup)
1640 {
1641 	clk_prepare_enable(qup->clk);
1642 	clk_prepare_enable(qup->pclk);
1643 }
1644 
1645 static void qup_i2c_disable_clocks(struct qup_i2c_dev *qup)
1646 {
1647 	u32 config;
1648 
1649 	qup_i2c_change_state(qup, QUP_RESET_STATE);
1650 	clk_disable_unprepare(qup->clk);
1651 	config = readl(qup->base + QUP_CONFIG);
1652 	config |= QUP_CLOCK_AUTO_GATE;
1653 	writel(config, qup->base + QUP_CONFIG);
1654 	clk_disable_unprepare(qup->pclk);
1655 }
1656 
1657 static const struct acpi_device_id qup_i2c_acpi_match[] = {
1658 	{ "QCOM8010"},
1659 	{ },
1660 };
1661 MODULE_DEVICE_TABLE(acpi, qup_i2c_acpi_match);
1662 
1663 static int qup_i2c_probe(struct platform_device *pdev)
1664 {
1665 	static const int blk_sizes[] = {4, 16, 32};
1666 	struct qup_i2c_dev *qup;
1667 	unsigned long one_bit_t;
1668 	struct resource *res;
1669 	u32 io_mode, hw_ver, size;
1670 	int ret, fs_div, hs_div;
1671 	u32 src_clk_freq = DEFAULT_SRC_CLK;
1672 	u32 clk_freq = DEFAULT_CLK_FREQ;
1673 	int blocks;
1674 	bool is_qup_v1;
1675 
1676 	qup = devm_kzalloc(&pdev->dev, sizeof(*qup), GFP_KERNEL);
1677 	if (!qup)
1678 		return -ENOMEM;
1679 
1680 	qup->dev = &pdev->dev;
1681 	init_completion(&qup->xfer);
1682 	platform_set_drvdata(pdev, qup);
1683 
1684 	if (scl_freq) {
1685 		dev_notice(qup->dev, "Using override frequency of %u\n", scl_freq);
1686 		clk_freq = scl_freq;
1687 	} else {
1688 		ret = device_property_read_u32(qup->dev, "clock-frequency", &clk_freq);
1689 		if (ret) {
1690 			dev_notice(qup->dev, "using default clock-frequency %d",
1691 				DEFAULT_CLK_FREQ);
1692 		}
1693 	}
1694 
1695 	if (of_device_is_compatible(pdev->dev.of_node, "qcom,i2c-qup-v1.1.1")) {
1696 		qup->adap.algo = &qup_i2c_algo;
1697 		qup->adap.quirks = &qup_i2c_quirks;
1698 		is_qup_v1 = true;
1699 	} else {
1700 		qup->adap.algo = &qup_i2c_algo_v2;
1701 		qup->adap.quirks = &qup_i2c_quirks_v2;
1702 		is_qup_v1 = false;
1703 		if (acpi_match_device(qup_i2c_acpi_match, qup->dev))
1704 			goto nodma;
1705 		else
1706 			ret = qup_i2c_req_dma(qup);
1707 
1708 		if (ret == -EPROBE_DEFER)
1709 			goto fail_dma;
1710 		else if (ret != 0)
1711 			goto nodma;
1712 
1713 		qup->max_xfer_sg_len = (MX_BLOCKS << 1);
1714 		blocks = (MX_DMA_BLOCKS << 1) + 1;
1715 		qup->btx.sg = devm_kcalloc(&pdev->dev,
1716 					   blocks, sizeof(*qup->btx.sg),
1717 					   GFP_KERNEL);
1718 		if (!qup->btx.sg) {
1719 			ret = -ENOMEM;
1720 			goto fail_dma;
1721 		}
1722 		sg_init_table(qup->btx.sg, blocks);
1723 
1724 		qup->brx.sg = devm_kcalloc(&pdev->dev,
1725 					   blocks, sizeof(*qup->brx.sg),
1726 					   GFP_KERNEL);
1727 		if (!qup->brx.sg) {
1728 			ret = -ENOMEM;
1729 			goto fail_dma;
1730 		}
1731 		sg_init_table(qup->brx.sg, blocks);
1732 
1733 		/* 2 tag bytes for each block + 5 for start, stop tags */
1734 		size = blocks * 2 + 5;
1735 
1736 		qup->start_tag.start = devm_kzalloc(&pdev->dev,
1737 						    size, GFP_KERNEL);
1738 		if (!qup->start_tag.start) {
1739 			ret = -ENOMEM;
1740 			goto fail_dma;
1741 		}
1742 
1743 		qup->brx.tag.start = devm_kzalloc(&pdev->dev, 2, GFP_KERNEL);
1744 		if (!qup->brx.tag.start) {
1745 			ret = -ENOMEM;
1746 			goto fail_dma;
1747 		}
1748 
1749 		qup->btx.tag.start = devm_kzalloc(&pdev->dev, 2, GFP_KERNEL);
1750 		if (!qup->btx.tag.start) {
1751 			ret = -ENOMEM;
1752 			goto fail_dma;
1753 		}
1754 		qup->is_dma = true;
1755 	}
1756 
1757 nodma:
1758 	/* We support frequencies up to FAST Mode Plus (1MHz) */
1759 	if (!clk_freq || clk_freq > I2C_FAST_MODE_PLUS_FREQ) {
1760 		dev_err(qup->dev, "clock frequency not supported %d\n",
1761 			clk_freq);
1762 		return -EINVAL;
1763 	}
1764 
1765 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1766 	qup->base = devm_ioremap_resource(qup->dev, res);
1767 	if (IS_ERR(qup->base))
1768 		return PTR_ERR(qup->base);
1769 
1770 	qup->irq = platform_get_irq(pdev, 0);
1771 	if (qup->irq < 0) {
1772 		dev_err(qup->dev, "No IRQ defined\n");
1773 		return qup->irq;
1774 	}
1775 
1776 	if (has_acpi_companion(qup->dev)) {
1777 		ret = device_property_read_u32(qup->dev,
1778 				"src-clock-hz", &src_clk_freq);
1779 		if (ret) {
1780 			dev_notice(qup->dev, "using default src-clock-hz %d",
1781 				DEFAULT_SRC_CLK);
1782 		}
1783 		ACPI_COMPANION_SET(&qup->adap.dev, ACPI_COMPANION(qup->dev));
1784 	} else {
1785 		qup->clk = devm_clk_get(qup->dev, "core");
1786 		if (IS_ERR(qup->clk)) {
1787 			dev_err(qup->dev, "Could not get core clock\n");
1788 			return PTR_ERR(qup->clk);
1789 		}
1790 
1791 		qup->pclk = devm_clk_get(qup->dev, "iface");
1792 		if (IS_ERR(qup->pclk)) {
1793 			dev_err(qup->dev, "Could not get iface clock\n");
1794 			return PTR_ERR(qup->pclk);
1795 		}
1796 		qup_i2c_enable_clocks(qup);
1797 		src_clk_freq = clk_get_rate(qup->clk);
1798 	}
1799 
1800 	/*
1801 	 * Bootloaders might leave a pending interrupt on certain QUP's,
1802 	 * so we reset the core before registering for interrupts.
1803 	 */
1804 	writel(1, qup->base + QUP_SW_RESET);
1805 	ret = qup_i2c_poll_state_valid(qup);
1806 	if (ret)
1807 		goto fail;
1808 
1809 	ret = devm_request_irq(qup->dev, qup->irq, qup_i2c_interrupt,
1810 			       IRQF_TRIGGER_HIGH, "i2c_qup", qup);
1811 	if (ret) {
1812 		dev_err(qup->dev, "Request %d IRQ failed\n", qup->irq);
1813 		goto fail;
1814 	}
1815 	disable_irq(qup->irq);
1816 
1817 	hw_ver = readl(qup->base + QUP_HW_VERSION);
1818 	dev_dbg(qup->dev, "Revision %x\n", hw_ver);
1819 
1820 	io_mode = readl(qup->base + QUP_IO_MODE);
1821 
1822 	/*
1823 	 * The block/fifo size w.r.t. 'actual data' is 1/2 due to 'tag'
1824 	 * associated with each byte written/received
1825 	 */
1826 	size = QUP_OUTPUT_BLOCK_SIZE(io_mode);
1827 	if (size >= ARRAY_SIZE(blk_sizes)) {
1828 		ret = -EIO;
1829 		goto fail;
1830 	}
1831 	qup->out_blk_sz = blk_sizes[size];
1832 
1833 	size = QUP_INPUT_BLOCK_SIZE(io_mode);
1834 	if (size >= ARRAY_SIZE(blk_sizes)) {
1835 		ret = -EIO;
1836 		goto fail;
1837 	}
1838 	qup->in_blk_sz = blk_sizes[size];
1839 
1840 	if (is_qup_v1) {
1841 		/*
1842 		 * in QUP v1, QUP_CONFIG uses N as 15 i.e 16 bits constitutes a
1843 		 * single transfer but the block size is in bytes so divide the
1844 		 * in_blk_sz and out_blk_sz by 2
1845 		 */
1846 		qup->in_blk_sz /= 2;
1847 		qup->out_blk_sz /= 2;
1848 		qup->write_tx_fifo = qup_i2c_write_tx_fifo_v1;
1849 		qup->read_rx_fifo = qup_i2c_read_rx_fifo_v1;
1850 		qup->write_rx_tags = qup_i2c_write_rx_tags_v1;
1851 	} else {
1852 		qup->write_tx_fifo = qup_i2c_write_tx_fifo_v2;
1853 		qup->read_rx_fifo = qup_i2c_read_rx_fifo_v2;
1854 		qup->write_rx_tags = qup_i2c_write_rx_tags_v2;
1855 	}
1856 
1857 	size = QUP_OUTPUT_FIFO_SIZE(io_mode);
1858 	qup->out_fifo_sz = qup->out_blk_sz * (2 << size);
1859 
1860 	size = QUP_INPUT_FIFO_SIZE(io_mode);
1861 	qup->in_fifo_sz = qup->in_blk_sz * (2 << size);
1862 
1863 	hs_div = 3;
1864 	if (clk_freq <= I2C_STANDARD_FREQ) {
1865 		fs_div = ((src_clk_freq / clk_freq) / 2) - 3;
1866 		qup->clk_ctl = (hs_div << 8) | (fs_div & 0xff);
1867 	} else {
1868 		/* 33%/66% duty cycle */
1869 		fs_div = ((src_clk_freq / clk_freq) - 6) * 2 / 3;
1870 		qup->clk_ctl = ((fs_div / 2) << 16) | (hs_div << 8) | (fs_div & 0xff);
1871 	}
1872 
1873 	/*
1874 	 * Time it takes for a byte to be clocked out on the bus.
1875 	 * Each byte takes 9 clock cycles (8 bits + 1 ack).
1876 	 */
1877 	one_bit_t = (USEC_PER_SEC / clk_freq) + 1;
1878 	qup->one_byte_t = one_bit_t * 9;
1879 	qup->xfer_timeout = TOUT_MIN * HZ +
1880 		usecs_to_jiffies(MX_DMA_TX_RX_LEN * qup->one_byte_t);
1881 
1882 	dev_dbg(qup->dev, "IN:block:%d, fifo:%d, OUT:block:%d, fifo:%d\n",
1883 		qup->in_blk_sz, qup->in_fifo_sz,
1884 		qup->out_blk_sz, qup->out_fifo_sz);
1885 
1886 	i2c_set_adapdata(&qup->adap, qup);
1887 	qup->adap.dev.parent = qup->dev;
1888 	qup->adap.dev.of_node = pdev->dev.of_node;
1889 	qup->is_last = true;
1890 
1891 	strlcpy(qup->adap.name, "QUP I2C adapter", sizeof(qup->adap.name));
1892 
1893 	pm_runtime_set_autosuspend_delay(qup->dev, MSEC_PER_SEC);
1894 	pm_runtime_use_autosuspend(qup->dev);
1895 	pm_runtime_set_active(qup->dev);
1896 	pm_runtime_enable(qup->dev);
1897 
1898 	ret = i2c_add_adapter(&qup->adap);
1899 	if (ret)
1900 		goto fail_runtime;
1901 
1902 	return 0;
1903 
1904 fail_runtime:
1905 	pm_runtime_disable(qup->dev);
1906 	pm_runtime_set_suspended(qup->dev);
1907 fail:
1908 	qup_i2c_disable_clocks(qup);
1909 fail_dma:
1910 	if (qup->btx.dma)
1911 		dma_release_channel(qup->btx.dma);
1912 	if (qup->brx.dma)
1913 		dma_release_channel(qup->brx.dma);
1914 	return ret;
1915 }
1916 
1917 static int qup_i2c_remove(struct platform_device *pdev)
1918 {
1919 	struct qup_i2c_dev *qup = platform_get_drvdata(pdev);
1920 
1921 	if (qup->is_dma) {
1922 		dma_release_channel(qup->btx.dma);
1923 		dma_release_channel(qup->brx.dma);
1924 	}
1925 
1926 	disable_irq(qup->irq);
1927 	qup_i2c_disable_clocks(qup);
1928 	i2c_del_adapter(&qup->adap);
1929 	pm_runtime_disable(qup->dev);
1930 	pm_runtime_set_suspended(qup->dev);
1931 	return 0;
1932 }
1933 
1934 #ifdef CONFIG_PM
1935 static int qup_i2c_pm_suspend_runtime(struct device *device)
1936 {
1937 	struct qup_i2c_dev *qup = dev_get_drvdata(device);
1938 
1939 	dev_dbg(device, "pm_runtime: suspending...\n");
1940 	qup_i2c_disable_clocks(qup);
1941 	return 0;
1942 }
1943 
1944 static int qup_i2c_pm_resume_runtime(struct device *device)
1945 {
1946 	struct qup_i2c_dev *qup = dev_get_drvdata(device);
1947 
1948 	dev_dbg(device, "pm_runtime: resuming...\n");
1949 	qup_i2c_enable_clocks(qup);
1950 	return 0;
1951 }
1952 #endif
1953 
1954 #ifdef CONFIG_PM_SLEEP
1955 static int qup_i2c_suspend(struct device *device)
1956 {
1957 	if (!pm_runtime_suspended(device))
1958 		return qup_i2c_pm_suspend_runtime(device);
1959 	return 0;
1960 }
1961 
1962 static int qup_i2c_resume(struct device *device)
1963 {
1964 	qup_i2c_pm_resume_runtime(device);
1965 	pm_runtime_mark_last_busy(device);
1966 	pm_request_autosuspend(device);
1967 	return 0;
1968 }
1969 #endif
1970 
1971 static const struct dev_pm_ops qup_i2c_qup_pm_ops = {
1972 	SET_SYSTEM_SLEEP_PM_OPS(
1973 		qup_i2c_suspend,
1974 		qup_i2c_resume)
1975 	SET_RUNTIME_PM_OPS(
1976 		qup_i2c_pm_suspend_runtime,
1977 		qup_i2c_pm_resume_runtime,
1978 		NULL)
1979 };
1980 
1981 static const struct of_device_id qup_i2c_dt_match[] = {
1982 	{ .compatible = "qcom,i2c-qup-v1.1.1" },
1983 	{ .compatible = "qcom,i2c-qup-v2.1.1" },
1984 	{ .compatible = "qcom,i2c-qup-v2.2.1" },
1985 	{}
1986 };
1987 MODULE_DEVICE_TABLE(of, qup_i2c_dt_match);
1988 
1989 static struct platform_driver qup_i2c_driver = {
1990 	.probe  = qup_i2c_probe,
1991 	.remove = qup_i2c_remove,
1992 	.driver = {
1993 		.name = "i2c_qup",
1994 		.pm = &qup_i2c_qup_pm_ops,
1995 		.of_match_table = qup_i2c_dt_match,
1996 		.acpi_match_table = ACPI_PTR(qup_i2c_acpi_match),
1997 	},
1998 };
1999 
2000 module_platform_driver(qup_i2c_driver);
2001 
2002 MODULE_LICENSE("GPL v2");
2003 MODULE_ALIAS("platform:i2c_qup");
2004