1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2014 MediaTek Inc.
4 * Author: Xudong Chen <xudong.chen@mediatek.com>
5 */
6
7#include <linux/clk.h>
8#include <linux/completion.h>
9#include <linux/delay.h>
10#include <linux/device.h>
11#include <linux/dma-mapping.h>
12#include <linux/err.h>
13#include <linux/errno.h>
14#include <linux/i2c.h>
15#include <linux/init.h>
16#include <linux/interrupt.h>
17#include <linux/io.h>
18#include <linux/kernel.h>
19#include <linux/mm.h>
20#include <linux/module.h>
21#include <linux/of_address.h>
22#include <linux/of_device.h>
23#include <linux/of_irq.h>
24#include <linux/platform_device.h>
25#include <linux/scatterlist.h>
26#include <linux/sched.h>
27#include <linux/slab.h>
28
29#define I2C_RS_TRANSFER			(1 << 4)
30#define I2C_ARB_LOST			(1 << 3)
31#define I2C_HS_NACKERR			(1 << 2)
32#define I2C_ACKERR			(1 << 1)
33#define I2C_TRANSAC_COMP		(1 << 0)
34#define I2C_TRANSAC_START		(1 << 0)
35#define I2C_RS_MUL_CNFG			(1 << 15)
36#define I2C_RS_MUL_TRIG			(1 << 14)
37#define I2C_DCM_DISABLE			0x0000
38#define I2C_IO_CONFIG_OPEN_DRAIN	0x0003
39#define I2C_IO_CONFIG_PUSH_PULL		0x0000
40#define I2C_SOFT_RST			0x0001
41#define I2C_HANDSHAKE_RST		0x0020
42#define I2C_FIFO_ADDR_CLR		0x0001
43#define I2C_DELAY_LEN			0x0002
44#define I2C_ST_START_CON		0x8001
45#define I2C_FS_START_CON		0x1800
46#define I2C_TIME_CLR_VALUE		0x0000
47#define I2C_TIME_DEFAULT_VALUE		0x0003
48#define I2C_WRRD_TRANAC_VALUE		0x0002
49#define I2C_RD_TRANAC_VALUE		0x0001
50#define I2C_SCL_MIS_COMP_VALUE		0x0000
51#define I2C_CHN_CLR_FLAG		0x0000
52
53#define I2C_DMA_CON_TX			0x0000
54#define I2C_DMA_CON_RX			0x0001
55#define I2C_DMA_ASYNC_MODE		0x0004
56#define I2C_DMA_SKIP_CONFIG		0x0010
57#define I2C_DMA_DIR_CHANGE		0x0200
58#define I2C_DMA_START_EN		0x0001
59#define I2C_DMA_INT_FLAG_NONE		0x0000
60#define I2C_DMA_CLR_FLAG		0x0000
61#define I2C_DMA_WARM_RST		0x0001
62#define I2C_DMA_HARD_RST		0x0002
63#define I2C_DMA_HANDSHAKE_RST		0x0004
64
65#define MAX_SAMPLE_CNT_DIV		8
66#define MAX_STEP_CNT_DIV		64
67#define MAX_CLOCK_DIV			256
68#define MAX_HS_STEP_CNT_DIV		8
69#define I2C_STANDARD_MODE_BUFFER	(1000 / 2)
70#define I2C_FAST_MODE_BUFFER		(300 / 2)
71#define I2C_FAST_MODE_PLUS_BUFFER	(20 / 2)
72
73#define I2C_CONTROL_RS                  (0x1 << 1)
74#define I2C_CONTROL_DMA_EN              (0x1 << 2)
75#define I2C_CONTROL_CLK_EXT_EN          (0x1 << 3)
76#define I2C_CONTROL_DIR_CHANGE          (0x1 << 4)
77#define I2C_CONTROL_ACKERR_DET_EN       (0x1 << 5)
78#define I2C_CONTROL_TRANSFER_LEN_CHANGE (0x1 << 6)
79#define I2C_CONTROL_DMAACK_EN           (0x1 << 8)
80#define I2C_CONTROL_ASYNC_MODE          (0x1 << 9)
81#define I2C_CONTROL_WRAPPER             (0x1 << 0)
82
83#define I2C_DRV_NAME		"i2c-mt65xx"
84
85enum DMA_REGS_OFFSET {
86	OFFSET_INT_FLAG = 0x0,
87	OFFSET_INT_EN = 0x04,
88	OFFSET_EN = 0x08,
89	OFFSET_RST = 0x0c,
90	OFFSET_CON = 0x18,
91	OFFSET_TX_MEM_ADDR = 0x1c,
92	OFFSET_RX_MEM_ADDR = 0x20,
93	OFFSET_TX_LEN = 0x24,
94	OFFSET_RX_LEN = 0x28,
95	OFFSET_TX_4G_MODE = 0x54,
96	OFFSET_RX_4G_MODE = 0x58,
97};
98
99enum i2c_trans_st_rs {
100	I2C_TRANS_STOP = 0,
101	I2C_TRANS_REPEATED_START,
102};
103
104enum mtk_trans_op {
105	I2C_MASTER_WR = 1,
106	I2C_MASTER_RD,
107	I2C_MASTER_WRRD,
108};
109
110enum I2C_REGS_OFFSET {
111	OFFSET_DATA_PORT,
112	OFFSET_SLAVE_ADDR,
113	OFFSET_INTR_MASK,
114	OFFSET_INTR_STAT,
115	OFFSET_CONTROL,
116	OFFSET_TRANSFER_LEN,
117	OFFSET_TRANSAC_LEN,
118	OFFSET_DELAY_LEN,
119	OFFSET_TIMING,
120	OFFSET_START,
121	OFFSET_EXT_CONF,
122	OFFSET_FIFO_STAT,
123	OFFSET_FIFO_THRESH,
124	OFFSET_FIFO_ADDR_CLR,
125	OFFSET_IO_CONFIG,
126	OFFSET_RSV_DEBUG,
127	OFFSET_HS,
128	OFFSET_SOFTRESET,
129	OFFSET_DCM_EN,
130	OFFSET_PATH_DIR,
131	OFFSET_DEBUGSTAT,
132	OFFSET_DEBUGCTRL,
133	OFFSET_TRANSFER_LEN_AUX,
134	OFFSET_CLOCK_DIV,
135	OFFSET_LTIMING,
136	OFFSET_SCL_HIGH_LOW_RATIO,
137	OFFSET_HS_SCL_HIGH_LOW_RATIO,
138	OFFSET_SCL_MIS_COMP_POINT,
139	OFFSET_STA_STO_AC_TIMING,
140	OFFSET_HS_STA_STO_AC_TIMING,
141	OFFSET_SDA_TIMING,
142};
143
144static const u16 mt_i2c_regs_v1[] = {
145	[OFFSET_DATA_PORT] = 0x0,
146	[OFFSET_SLAVE_ADDR] = 0x4,
147	[OFFSET_INTR_MASK] = 0x8,
148	[OFFSET_INTR_STAT] = 0xc,
149	[OFFSET_CONTROL] = 0x10,
150	[OFFSET_TRANSFER_LEN] = 0x14,
151	[OFFSET_TRANSAC_LEN] = 0x18,
152	[OFFSET_DELAY_LEN] = 0x1c,
153	[OFFSET_TIMING] = 0x20,
154	[OFFSET_START] = 0x24,
155	[OFFSET_EXT_CONF] = 0x28,
156	[OFFSET_FIFO_STAT] = 0x30,
157	[OFFSET_FIFO_THRESH] = 0x34,
158	[OFFSET_FIFO_ADDR_CLR] = 0x38,
159	[OFFSET_IO_CONFIG] = 0x40,
160	[OFFSET_RSV_DEBUG] = 0x44,
161	[OFFSET_HS] = 0x48,
162	[OFFSET_SOFTRESET] = 0x50,
163	[OFFSET_DCM_EN] = 0x54,
164	[OFFSET_PATH_DIR] = 0x60,
165	[OFFSET_DEBUGSTAT] = 0x64,
166	[OFFSET_DEBUGCTRL] = 0x68,
167	[OFFSET_TRANSFER_LEN_AUX] = 0x6c,
168	[OFFSET_CLOCK_DIV] = 0x70,
169	[OFFSET_SCL_HIGH_LOW_RATIO] = 0x74,
170	[OFFSET_HS_SCL_HIGH_LOW_RATIO] = 0x78,
171	[OFFSET_SCL_MIS_COMP_POINT] = 0x7C,
172	[OFFSET_STA_STO_AC_TIMING] = 0x80,
173	[OFFSET_HS_STA_STO_AC_TIMING] = 0x84,
174	[OFFSET_SDA_TIMING] = 0x88,
175};
176
177static const u16 mt_i2c_regs_v2[] = {
178	[OFFSET_DATA_PORT] = 0x0,
179	[OFFSET_SLAVE_ADDR] = 0x4,
180	[OFFSET_INTR_MASK] = 0x8,
181	[OFFSET_INTR_STAT] = 0xc,
182	[OFFSET_CONTROL] = 0x10,
183	[OFFSET_TRANSFER_LEN] = 0x14,
184	[OFFSET_TRANSAC_LEN] = 0x18,
185	[OFFSET_DELAY_LEN] = 0x1c,
186	[OFFSET_TIMING] = 0x20,
187	[OFFSET_START] = 0x24,
188	[OFFSET_EXT_CONF] = 0x28,
189	[OFFSET_LTIMING] = 0x2c,
190	[OFFSET_HS] = 0x30,
191	[OFFSET_IO_CONFIG] = 0x34,
192	[OFFSET_FIFO_ADDR_CLR] = 0x38,
193	[OFFSET_SDA_TIMING] = 0x3c,
194	[OFFSET_TRANSFER_LEN_AUX] = 0x44,
195	[OFFSET_CLOCK_DIV] = 0x48,
196	[OFFSET_SOFTRESET] = 0x50,
197	[OFFSET_SCL_MIS_COMP_POINT] = 0x90,
198	[OFFSET_DEBUGSTAT] = 0xe4,
199	[OFFSET_DEBUGCTRL] = 0xe8,
200	[OFFSET_FIFO_STAT] = 0xf4,
201	[OFFSET_FIFO_THRESH] = 0xf8,
202	[OFFSET_DCM_EN] = 0xf88,
203};
204
205struct mtk_i2c_compatible {
206	const struct i2c_adapter_quirks *quirks;
207	const u16 *regs;
208	unsigned char pmic_i2c: 1;
209	unsigned char dcm: 1;
210	unsigned char auto_restart: 1;
211	unsigned char aux_len_reg: 1;
212	unsigned char timing_adjust: 1;
213	unsigned char dma_sync: 1;
214	unsigned char ltiming_adjust: 1;
215	unsigned char apdma_sync: 1;
216	unsigned char max_dma_support;
217};
218
219struct mtk_i2c_ac_timing {
220	u16 htiming;
221	u16 ltiming;
222	u16 hs;
223	u16 ext;
224	u16 inter_clk_div;
225	u16 scl_hl_ratio;
226	u16 hs_scl_hl_ratio;
227	u16 sta_stop;
228	u16 hs_sta_stop;
229	u16 sda_timing;
230};
231
232struct mtk_i2c {
233	struct i2c_adapter adap;	/* i2c host adapter */
234	struct device *dev;
235	struct completion msg_complete;
236
237	/* set in i2c probe */
238	void __iomem *base;		/* i2c base addr */
239	void __iomem *pdmabase;		/* dma base address*/
240	struct clk *clk_main;		/* main clock for i2c bus */
241	struct clk *clk_dma;		/* DMA clock for i2c via DMA */
242	struct clk *clk_pmic;		/* PMIC clock for i2c from PMIC */
243	struct clk *clk_arb;		/* Arbitrator clock for i2c */
244	bool have_pmic;			/* can use i2c pins from PMIC */
245	bool use_push_pull;		/* IO config push-pull mode */
246
247	u16 irq_stat;			/* interrupt status */
248	unsigned int clk_src_div;
249	unsigned int speed_hz;		/* The speed in transfer */
250	enum mtk_trans_op op;
251	u16 timing_reg;
252	u16 high_speed_reg;
253	u16 ltiming_reg;
254	unsigned char auto_restart;
255	bool ignore_restart_irq;
256	struct mtk_i2c_ac_timing ac_timing;
257	const struct mtk_i2c_compatible *dev_comp;
258};
259
260/**
261 * struct i2c_spec_values:
262 * @min_low_ns: min LOW period of the SCL clock
263 * @min_su_sta_ns: min set-up time for a repeated START condition
264 * @max_hd_dat_ns: max data hold time
265 * @min_su_dat_ns: min data set-up time
266 */
267struct i2c_spec_values {
268	unsigned int min_low_ns;
269	unsigned int min_su_sta_ns;
270	unsigned int max_hd_dat_ns;
271	unsigned int min_su_dat_ns;
272};
273
274static const struct i2c_spec_values standard_mode_spec = {
275	.min_low_ns = 4700 + I2C_STANDARD_MODE_BUFFER,
276	.min_su_sta_ns = 4700 + I2C_STANDARD_MODE_BUFFER,
277	.max_hd_dat_ns = 3450 - I2C_STANDARD_MODE_BUFFER,
278	.min_su_dat_ns = 250 + I2C_STANDARD_MODE_BUFFER,
279};
280
281static const struct i2c_spec_values fast_mode_spec = {
282	.min_low_ns = 1300 + I2C_FAST_MODE_BUFFER,
283	.min_su_sta_ns = 600 + I2C_FAST_MODE_BUFFER,
284	.max_hd_dat_ns = 900 - I2C_FAST_MODE_BUFFER,
285	.min_su_dat_ns = 100 + I2C_FAST_MODE_BUFFER,
286};
287
288static const struct i2c_spec_values fast_mode_plus_spec = {
289	.min_low_ns = 500 + I2C_FAST_MODE_PLUS_BUFFER,
290	.min_su_sta_ns = 260 + I2C_FAST_MODE_PLUS_BUFFER,
291	.max_hd_dat_ns = 400 - I2C_FAST_MODE_PLUS_BUFFER,
292	.min_su_dat_ns = 50 + I2C_FAST_MODE_PLUS_BUFFER,
293};
294
295static const struct i2c_adapter_quirks mt6577_i2c_quirks = {
296	.flags = I2C_AQ_COMB_WRITE_THEN_READ,
297	.max_num_msgs = 1,
298	.max_write_len = 255,
299	.max_read_len = 255,
300	.max_comb_1st_msg_len = 255,
301	.max_comb_2nd_msg_len = 31,
302};
303
304static const struct i2c_adapter_quirks mt7622_i2c_quirks = {
305	.max_num_msgs = 255,
306};
307
308static const struct i2c_adapter_quirks mt8183_i2c_quirks = {
309	.flags = I2C_AQ_NO_ZERO_LEN,
310};
311
312static const struct mtk_i2c_compatible mt2712_compat = {
313	.regs = mt_i2c_regs_v1,
314	.pmic_i2c = 0,
315	.dcm = 1,
316	.auto_restart = 1,
317	.aux_len_reg = 1,
318	.timing_adjust = 1,
319	.dma_sync = 0,
320	.ltiming_adjust = 0,
321	.apdma_sync = 0,
322	.max_dma_support = 33,
323};
324
325static const struct mtk_i2c_compatible mt6577_compat = {
326	.quirks = &mt6577_i2c_quirks,
327	.regs = mt_i2c_regs_v1,
328	.pmic_i2c = 0,
329	.dcm = 1,
330	.auto_restart = 0,
331	.aux_len_reg = 0,
332	.timing_adjust = 0,
333	.dma_sync = 0,
334	.ltiming_adjust = 0,
335	.apdma_sync = 0,
336	.max_dma_support = 32,
337};
338
339static const struct mtk_i2c_compatible mt6589_compat = {
340	.quirks = &mt6577_i2c_quirks,
341	.regs = mt_i2c_regs_v1,
342	.pmic_i2c = 1,
343	.dcm = 0,
344	.auto_restart = 0,
345	.aux_len_reg = 0,
346	.timing_adjust = 0,
347	.dma_sync = 0,
348	.ltiming_adjust = 0,
349	.apdma_sync = 0,
350	.max_dma_support = 32,
351};
352
353static const struct mtk_i2c_compatible mt7622_compat = {
354	.quirks = &mt7622_i2c_quirks,
355	.regs = mt_i2c_regs_v1,
356	.pmic_i2c = 0,
357	.dcm = 1,
358	.auto_restart = 1,
359	.aux_len_reg = 1,
360	.timing_adjust = 0,
361	.dma_sync = 0,
362	.ltiming_adjust = 0,
363	.apdma_sync = 0,
364	.max_dma_support = 32,
365};
366
367static const struct mtk_i2c_compatible mt8173_compat = {
368	.regs = mt_i2c_regs_v1,
369	.pmic_i2c = 0,
370	.dcm = 1,
371	.auto_restart = 1,
372	.aux_len_reg = 1,
373	.timing_adjust = 0,
374	.dma_sync = 0,
375	.ltiming_adjust = 0,
376	.apdma_sync = 0,
377	.max_dma_support = 33,
378};
379
380static const struct mtk_i2c_compatible mt8183_compat = {
381	.quirks = &mt8183_i2c_quirks,
382	.regs = mt_i2c_regs_v2,
383	.pmic_i2c = 0,
384	.dcm = 0,
385	.auto_restart = 1,
386	.aux_len_reg = 1,
387	.timing_adjust = 1,
388	.dma_sync = 1,
389	.ltiming_adjust = 1,
390	.apdma_sync = 0,
391	.max_dma_support = 33,
392};
393
394static const struct mtk_i2c_compatible mt8192_compat = {
395	.quirks = &mt8183_i2c_quirks,
396	.regs = mt_i2c_regs_v2,
397	.pmic_i2c = 0,
398	.dcm = 0,
399	.auto_restart = 1,
400	.aux_len_reg = 1,
401	.timing_adjust = 1,
402	.dma_sync = 1,
403	.ltiming_adjust = 1,
404	.apdma_sync = 1,
405	.max_dma_support = 36,
406};
407
408static const struct of_device_id mtk_i2c_of_match[] = {
409	{ .compatible = "mediatek,mt2712-i2c", .data = &mt2712_compat },
410	{ .compatible = "mediatek,mt6577-i2c", .data = &mt6577_compat },
411	{ .compatible = "mediatek,mt6589-i2c", .data = &mt6589_compat },
412	{ .compatible = "mediatek,mt7622-i2c", .data = &mt7622_compat },
413	{ .compatible = "mediatek,mt8173-i2c", .data = &mt8173_compat },
414	{ .compatible = "mediatek,mt8183-i2c", .data = &mt8183_compat },
415	{ .compatible = "mediatek,mt8192-i2c", .data = &mt8192_compat },
416	{}
417};
418MODULE_DEVICE_TABLE(of, mtk_i2c_of_match);
419
420static u16 mtk_i2c_readw(struct mtk_i2c *i2c, enum I2C_REGS_OFFSET reg)
421{
422	return readw(i2c->base + i2c->dev_comp->regs[reg]);
423}
424
425static void mtk_i2c_writew(struct mtk_i2c *i2c, u16 val,
426			   enum I2C_REGS_OFFSET reg)
427{
428	writew(val, i2c->base + i2c->dev_comp->regs[reg]);
429}
430
431static int mtk_i2c_clock_enable(struct mtk_i2c *i2c)
432{
433	int ret;
434
435	ret = clk_prepare_enable(i2c->clk_dma);
436	if (ret)
437		return ret;
438
439	ret = clk_prepare_enable(i2c->clk_main);
440	if (ret)
441		goto err_main;
442
443	if (i2c->have_pmic) {
444		ret = clk_prepare_enable(i2c->clk_pmic);
445		if (ret)
446			goto err_pmic;
447	}
448
449	if (i2c->clk_arb) {
450		ret = clk_prepare_enable(i2c->clk_arb);
451		if (ret)
452			goto err_arb;
453	}
454
455	return 0;
456
457err_arb:
458	if (i2c->have_pmic)
459		clk_disable_unprepare(i2c->clk_pmic);
460err_pmic:
461	clk_disable_unprepare(i2c->clk_main);
462err_main:
463	clk_disable_unprepare(i2c->clk_dma);
464
465	return ret;
466}
467
468static void mtk_i2c_clock_disable(struct mtk_i2c *i2c)
469{
470	if (i2c->clk_arb)
471		clk_disable_unprepare(i2c->clk_arb);
472
473	if (i2c->have_pmic)
474		clk_disable_unprepare(i2c->clk_pmic);
475
476	clk_disable_unprepare(i2c->clk_main);
477	clk_disable_unprepare(i2c->clk_dma);
478}
479
480static void mtk_i2c_init_hw(struct mtk_i2c *i2c)
481{
482	u16 control_reg;
483	u16 intr_stat_reg;
484	u16 ext_conf_val;
485
486	mtk_i2c_writew(i2c, I2C_CHN_CLR_FLAG, OFFSET_START);
487	intr_stat_reg = mtk_i2c_readw(i2c, OFFSET_INTR_STAT);
488	mtk_i2c_writew(i2c, intr_stat_reg, OFFSET_INTR_STAT);
489
490	if (i2c->dev_comp->apdma_sync) {
491		writel(I2C_DMA_WARM_RST, i2c->pdmabase + OFFSET_RST);
492		udelay(10);
493		writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST);
494		udelay(10);
495		writel(I2C_DMA_HANDSHAKE_RST | I2C_DMA_HARD_RST,
496		       i2c->pdmabase + OFFSET_RST);
497		mtk_i2c_writew(i2c, I2C_HANDSHAKE_RST | I2C_SOFT_RST,
498			       OFFSET_SOFTRESET);
499		udelay(10);
500		writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST);
501		mtk_i2c_writew(i2c, I2C_CHN_CLR_FLAG, OFFSET_SOFTRESET);
502	} else {
503		writel(I2C_DMA_HARD_RST, i2c->pdmabase + OFFSET_RST);
504		udelay(50);
505		writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_RST);
506		mtk_i2c_writew(i2c, I2C_SOFT_RST, OFFSET_SOFTRESET);
507	}
508
509	/* Set ioconfig */
510	if (i2c->use_push_pull)
511		mtk_i2c_writew(i2c, I2C_IO_CONFIG_PUSH_PULL, OFFSET_IO_CONFIG);
512	else
513		mtk_i2c_writew(i2c, I2C_IO_CONFIG_OPEN_DRAIN, OFFSET_IO_CONFIG);
514
515	if (i2c->dev_comp->dcm)
516		mtk_i2c_writew(i2c, I2C_DCM_DISABLE, OFFSET_DCM_EN);
517
518	mtk_i2c_writew(i2c, i2c->timing_reg, OFFSET_TIMING);
519	mtk_i2c_writew(i2c, i2c->high_speed_reg, OFFSET_HS);
520	if (i2c->dev_comp->ltiming_adjust)
521		mtk_i2c_writew(i2c, i2c->ltiming_reg, OFFSET_LTIMING);
522
523	if (i2c->speed_hz <= I2C_MAX_STANDARD_MODE_FREQ)
524		ext_conf_val = I2C_ST_START_CON;
525	else
526		ext_conf_val = I2C_FS_START_CON;
527
528	if (i2c->dev_comp->timing_adjust) {
529		ext_conf_val = i2c->ac_timing.ext;
530		mtk_i2c_writew(i2c, i2c->ac_timing.inter_clk_div,
531			       OFFSET_CLOCK_DIV);
532		mtk_i2c_writew(i2c, I2C_SCL_MIS_COMP_VALUE,
533			       OFFSET_SCL_MIS_COMP_POINT);
534		mtk_i2c_writew(i2c, i2c->ac_timing.sda_timing,
535			       OFFSET_SDA_TIMING);
536
537		if (i2c->dev_comp->ltiming_adjust) {
538			mtk_i2c_writew(i2c, i2c->ac_timing.htiming,
539				       OFFSET_TIMING);
540			mtk_i2c_writew(i2c, i2c->ac_timing.hs, OFFSET_HS);
541			mtk_i2c_writew(i2c, i2c->ac_timing.ltiming,
542				       OFFSET_LTIMING);
543		} else {
544			mtk_i2c_writew(i2c, i2c->ac_timing.scl_hl_ratio,
545				       OFFSET_SCL_HIGH_LOW_RATIO);
546			mtk_i2c_writew(i2c, i2c->ac_timing.hs_scl_hl_ratio,
547				       OFFSET_HS_SCL_HIGH_LOW_RATIO);
548			mtk_i2c_writew(i2c, i2c->ac_timing.sta_stop,
549				       OFFSET_STA_STO_AC_TIMING);
550			mtk_i2c_writew(i2c, i2c->ac_timing.hs_sta_stop,
551				       OFFSET_HS_STA_STO_AC_TIMING);
552		}
553	}
554	mtk_i2c_writew(i2c, ext_conf_val, OFFSET_EXT_CONF);
555
556	/* If use i2c pin from PMIC mt6397 side, need set PATH_DIR first */
557	if (i2c->have_pmic)
558		mtk_i2c_writew(i2c, I2C_CONTROL_WRAPPER, OFFSET_PATH_DIR);
559
560	control_reg = I2C_CONTROL_ACKERR_DET_EN |
561		      I2C_CONTROL_CLK_EXT_EN | I2C_CONTROL_DMA_EN;
562	if (i2c->dev_comp->dma_sync)
563		control_reg |= I2C_CONTROL_DMAACK_EN | I2C_CONTROL_ASYNC_MODE;
564
565	mtk_i2c_writew(i2c, control_reg, OFFSET_CONTROL);
566	mtk_i2c_writew(i2c, I2C_DELAY_LEN, OFFSET_DELAY_LEN);
567}
568
569static const struct i2c_spec_values *mtk_i2c_get_spec(unsigned int speed)
570{
571	if (speed <= I2C_MAX_STANDARD_MODE_FREQ)
572		return &standard_mode_spec;
573	else if (speed <= I2C_MAX_FAST_MODE_FREQ)
574		return &fast_mode_spec;
575	else
576		return &fast_mode_plus_spec;
577}
578
579static int mtk_i2c_max_step_cnt(unsigned int target_speed)
580{
581	if (target_speed > I2C_MAX_FAST_MODE_PLUS_FREQ)
582		return MAX_HS_STEP_CNT_DIV;
583	else
584		return MAX_STEP_CNT_DIV;
585}
586
587/*
588 * Check and Calculate i2c ac-timing
589 *
590 * Hardware design:
591 * sample_ns = (1000000000 * (sample_cnt + 1)) / clk_src
592 * xxx_cnt_div =  spec->min_xxx_ns / sample_ns
593 *
594 * Sample_ns is rounded down for xxx_cnt_div would be greater
595 * than the smallest spec.
596 * The sda_timing is chosen as the middle value between
597 * the largest and smallest.
598 */
599static int mtk_i2c_check_ac_timing(struct mtk_i2c *i2c,
600				   unsigned int clk_src,
601				   unsigned int check_speed,
602				   unsigned int step_cnt,
603				   unsigned int sample_cnt)
604{
605	const struct i2c_spec_values *spec;
606	unsigned int su_sta_cnt, low_cnt, high_cnt, max_step_cnt;
607	unsigned int sda_max, sda_min, clk_ns, max_sta_cnt = 0x3f;
608	unsigned int sample_ns = div_u64(1000000000ULL * (sample_cnt + 1),
609					 clk_src);
610
611	if (!i2c->dev_comp->timing_adjust)
612		return 0;
613
614	if (i2c->dev_comp->ltiming_adjust)
615		max_sta_cnt = 0x100;
616
617	spec = mtk_i2c_get_spec(check_speed);
618
619	if (i2c->dev_comp->ltiming_adjust)
620		clk_ns = 1000000000 / clk_src;
621	else
622		clk_ns = sample_ns / 2;
623
624	su_sta_cnt = DIV_ROUND_UP(spec->min_su_sta_ns, clk_ns);
625	if (su_sta_cnt > max_sta_cnt)
626		return -1;
627
628	low_cnt = DIV_ROUND_UP(spec->min_low_ns, sample_ns);
629	max_step_cnt = mtk_i2c_max_step_cnt(check_speed);
630	if ((2 * step_cnt) > low_cnt && low_cnt < max_step_cnt) {
631		if (low_cnt > step_cnt) {
632			high_cnt = 2 * step_cnt - low_cnt;
633		} else {
634			high_cnt = step_cnt;
635			low_cnt = step_cnt;
636		}
637	} else {
638		return -2;
639	}
640
641	sda_max = spec->max_hd_dat_ns / sample_ns;
642	if (sda_max > low_cnt)
643		sda_max = 0;
644
645	sda_min = DIV_ROUND_UP(spec->min_su_dat_ns, sample_ns);
646	if (sda_min < low_cnt)
647		sda_min = 0;
648
649	if (sda_min > sda_max)
650		return -3;
651
652	if (check_speed > I2C_MAX_FAST_MODE_PLUS_FREQ) {
653		if (i2c->dev_comp->ltiming_adjust) {
654			i2c->ac_timing.hs = I2C_TIME_DEFAULT_VALUE |
655				(sample_cnt << 12) | (high_cnt << 8);
656			i2c->ac_timing.ltiming &= ~GENMASK(15, 9);
657			i2c->ac_timing.ltiming |= (sample_cnt << 12) |
658				(low_cnt << 9);
659			i2c->ac_timing.ext &= ~GENMASK(7, 1);
660			i2c->ac_timing.ext |= (su_sta_cnt << 1) | (1 << 0);
661		} else {
662			i2c->ac_timing.hs_scl_hl_ratio = (1 << 12) |
663				(high_cnt << 6) | low_cnt;
664			i2c->ac_timing.hs_sta_stop = (su_sta_cnt << 8) |
665				su_sta_cnt;
666		}
667		i2c->ac_timing.sda_timing &= ~GENMASK(11, 6);
668		i2c->ac_timing.sda_timing |= (1 << 12) |
669			((sda_max + sda_min) / 2) << 6;
670	} else {
671		if (i2c->dev_comp->ltiming_adjust) {
672			i2c->ac_timing.htiming = (sample_cnt << 8) | (high_cnt);
673			i2c->ac_timing.ltiming = (sample_cnt << 6) | (low_cnt);
674			i2c->ac_timing.ext = (su_sta_cnt << 8) | (1 << 0);
675		} else {
676			i2c->ac_timing.scl_hl_ratio = (1 << 12) |
677				(high_cnt << 6) | low_cnt;
678			i2c->ac_timing.sta_stop = (su_sta_cnt << 8) |
679				su_sta_cnt;
680		}
681
682		i2c->ac_timing.sda_timing = (1 << 12) |
683			(sda_max + sda_min) / 2;
684	}
685
686	return 0;
687}
688
689/*
690 * Calculate i2c port speed
691 *
692 * Hardware design:
693 * i2c_bus_freq = parent_clk / (clock_div * 2 * sample_cnt * step_cnt)
694 * clock_div: fixed in hardware, but may be various in different SoCs
695 *
696 * The calculation want to pick the highest bus frequency that is still
697 * less than or equal to i2c->speed_hz. The calculation try to get
698 * sample_cnt and step_cn
699 */
700static int mtk_i2c_calculate_speed(struct mtk_i2c *i2c, unsigned int clk_src,
701				   unsigned int target_speed,
702				   unsigned int *timing_step_cnt,
703				   unsigned int *timing_sample_cnt)
704{
705	unsigned int step_cnt;
706	unsigned int sample_cnt;
707	unsigned int max_step_cnt;
708	unsigned int base_sample_cnt = MAX_SAMPLE_CNT_DIV;
709	unsigned int base_step_cnt;
710	unsigned int opt_div;
711	unsigned int best_mul;
712	unsigned int cnt_mul;
713	int ret = -EINVAL;
714
715	if (target_speed > I2C_MAX_HIGH_SPEED_MODE_FREQ)
716		target_speed = I2C_MAX_HIGH_SPEED_MODE_FREQ;
717
718	max_step_cnt = mtk_i2c_max_step_cnt(target_speed);
719	base_step_cnt = max_step_cnt;
720	/* Find the best combination */
721	opt_div = DIV_ROUND_UP(clk_src >> 1, target_speed);
722	best_mul = MAX_SAMPLE_CNT_DIV * max_step_cnt;
723
724	/* Search for the best pair (sample_cnt, step_cnt) with
725	 * 0 < sample_cnt < MAX_SAMPLE_CNT_DIV
726	 * 0 < step_cnt < max_step_cnt
727	 * sample_cnt * step_cnt >= opt_div
728	 * optimizing for sample_cnt * step_cnt being minimal
729	 */
730	for (sample_cnt = 1; sample_cnt <= MAX_SAMPLE_CNT_DIV; sample_cnt++) {
731		step_cnt = DIV_ROUND_UP(opt_div, sample_cnt);
732		cnt_mul = step_cnt * sample_cnt;
733		if (step_cnt > max_step_cnt)
734			continue;
735
736		if (cnt_mul < best_mul) {
737			ret = mtk_i2c_check_ac_timing(i2c, clk_src,
738				target_speed, step_cnt - 1, sample_cnt - 1);
739			if (ret)
740				continue;
741
742			best_mul = cnt_mul;
743			base_sample_cnt = sample_cnt;
744			base_step_cnt = step_cnt;
745			if (best_mul == opt_div)
746				break;
747		}
748	}
749
750	if (ret)
751		return -EINVAL;
752
753	sample_cnt = base_sample_cnt;
754	step_cnt = base_step_cnt;
755
756	if ((clk_src / (2 * sample_cnt * step_cnt)) > target_speed) {
757		/* In this case, hardware can't support such
758		 * low i2c_bus_freq
759		 */
760		dev_dbg(i2c->dev, "Unsupported speed (%uhz)\n",	target_speed);
761		return -EINVAL;
762	}
763
764	*timing_step_cnt = step_cnt - 1;
765	*timing_sample_cnt = sample_cnt - 1;
766
767	return 0;
768}
769
770static int mtk_i2c_set_speed(struct mtk_i2c *i2c, unsigned int parent_clk)
771{
772	unsigned int clk_src;
773	unsigned int step_cnt;
774	unsigned int sample_cnt;
775	unsigned int l_step_cnt;
776	unsigned int l_sample_cnt;
777	unsigned int target_speed;
778	unsigned int clk_div;
779	unsigned int max_clk_div;
780	int ret;
781
782	target_speed = i2c->speed_hz;
783	parent_clk /= i2c->clk_src_div;
784
785	if (i2c->dev_comp->timing_adjust)
786		max_clk_div = MAX_CLOCK_DIV;
787	else
788		max_clk_div = 1;
789
790	for (clk_div = 1; clk_div <= max_clk_div; clk_div++) {
791		clk_src = parent_clk / clk_div;
792
793		if (target_speed > I2C_MAX_FAST_MODE_PLUS_FREQ) {
794			/* Set master code speed register */
795			ret = mtk_i2c_calculate_speed(i2c, clk_src,
796						      I2C_MAX_FAST_MODE_FREQ,
797						      &l_step_cnt,
798						      &l_sample_cnt);
799			if (ret < 0)
800				continue;
801
802			i2c->timing_reg = (l_sample_cnt << 8) | l_step_cnt;
803
804			/* Set the high speed mode register */
805			ret = mtk_i2c_calculate_speed(i2c, clk_src,
806						      target_speed, &step_cnt,
807						      &sample_cnt);
808			if (ret < 0)
809				continue;
810
811			i2c->high_speed_reg = I2C_TIME_DEFAULT_VALUE |
812					(sample_cnt << 12) | (step_cnt << 8);
813
814			if (i2c->dev_comp->ltiming_adjust)
815				i2c->ltiming_reg =
816					(l_sample_cnt << 6) | l_step_cnt |
817					(sample_cnt << 12) | (step_cnt << 9);
818		} else {
819			ret = mtk_i2c_calculate_speed(i2c, clk_src,
820						      target_speed, &l_step_cnt,
821						      &l_sample_cnt);
822			if (ret < 0)
823				continue;
824
825			i2c->timing_reg = (l_sample_cnt << 8) | l_step_cnt;
826
827			/* Disable the high speed transaction */
828			i2c->high_speed_reg = I2C_TIME_CLR_VALUE;
829
830			if (i2c->dev_comp->ltiming_adjust)
831				i2c->ltiming_reg =
832					(l_sample_cnt << 6) | l_step_cnt;
833		}
834
835		break;
836	}
837
838	i2c->ac_timing.inter_clk_div = clk_div - 1;
839
840	return 0;
841}
842
843static int mtk_i2c_do_transfer(struct mtk_i2c *i2c, struct i2c_msg *msgs,
844			       int num, int left_num)
845{
846	u16 addr_reg;
847	u16 start_reg;
848	u16 control_reg;
849	u16 restart_flag = 0;
850	u16 dma_sync = 0;
851	u32 reg_4g_mode;
852	u8 *dma_rd_buf = NULL;
853	u8 *dma_wr_buf = NULL;
854	dma_addr_t rpaddr = 0;
855	dma_addr_t wpaddr = 0;
856	int ret;
857
858	i2c->irq_stat = 0;
859
860	if (i2c->auto_restart)
861		restart_flag = I2C_RS_TRANSFER;
862
863	reinit_completion(&i2c->msg_complete);
864
865	control_reg = mtk_i2c_readw(i2c, OFFSET_CONTROL) &
866			~(I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS);
867	if ((i2c->speed_hz > I2C_MAX_FAST_MODE_PLUS_FREQ) || (left_num >= 1))
868		control_reg |= I2C_CONTROL_RS;
869
870	if (i2c->op == I2C_MASTER_WRRD)
871		control_reg |= I2C_CONTROL_DIR_CHANGE | I2C_CONTROL_RS;
872
873	mtk_i2c_writew(i2c, control_reg, OFFSET_CONTROL);
874
875	addr_reg = i2c_8bit_addr_from_msg(msgs);
876	mtk_i2c_writew(i2c, addr_reg, OFFSET_SLAVE_ADDR);
877
878	/* Clear interrupt status */
879	mtk_i2c_writew(i2c, restart_flag | I2C_HS_NACKERR | I2C_ACKERR |
880			    I2C_ARB_LOST | I2C_TRANSAC_COMP, OFFSET_INTR_STAT);
881
882	mtk_i2c_writew(i2c, I2C_FIFO_ADDR_CLR, OFFSET_FIFO_ADDR_CLR);
883
884	/* Enable interrupt */
885	mtk_i2c_writew(i2c, restart_flag | I2C_HS_NACKERR | I2C_ACKERR |
886			    I2C_ARB_LOST | I2C_TRANSAC_COMP, OFFSET_INTR_MASK);
887
888	/* Set transfer and transaction len */
889	if (i2c->op == I2C_MASTER_WRRD) {
890		if (i2c->dev_comp->aux_len_reg) {
891			mtk_i2c_writew(i2c, msgs->len, OFFSET_TRANSFER_LEN);
892			mtk_i2c_writew(i2c, (msgs + 1)->len,
893					    OFFSET_TRANSFER_LEN_AUX);
894		} else {
895			mtk_i2c_writew(i2c, msgs->len | ((msgs + 1)->len) << 8,
896					    OFFSET_TRANSFER_LEN);
897		}
898		mtk_i2c_writew(i2c, I2C_WRRD_TRANAC_VALUE, OFFSET_TRANSAC_LEN);
899	} else {
900		mtk_i2c_writew(i2c, msgs->len, OFFSET_TRANSFER_LEN);
901		mtk_i2c_writew(i2c, num, OFFSET_TRANSAC_LEN);
902	}
903
904	if (i2c->dev_comp->apdma_sync) {
905		dma_sync = I2C_DMA_SKIP_CONFIG | I2C_DMA_ASYNC_MODE;
906		if (i2c->op == I2C_MASTER_WRRD)
907			dma_sync |= I2C_DMA_DIR_CHANGE;
908	}
909
910	/* Prepare buffer data to start transfer */
911	if (i2c->op == I2C_MASTER_RD) {
912		writel(I2C_DMA_INT_FLAG_NONE, i2c->pdmabase + OFFSET_INT_FLAG);
913		writel(I2C_DMA_CON_RX | dma_sync, i2c->pdmabase + OFFSET_CON);
914
915		dma_rd_buf = i2c_get_dma_safe_msg_buf(msgs, 1);
916		if (!dma_rd_buf)
917			return -ENOMEM;
918
919		rpaddr = dma_map_single(i2c->dev, dma_rd_buf,
920					msgs->len, DMA_FROM_DEVICE);
921		if (dma_mapping_error(i2c->dev, rpaddr)) {
922			i2c_put_dma_safe_msg_buf(dma_rd_buf, msgs, false);
923
924			return -ENOMEM;
925		}
926
927		if (i2c->dev_comp->max_dma_support > 32) {
928			reg_4g_mode = upper_32_bits(rpaddr);
929			writel(reg_4g_mode, i2c->pdmabase + OFFSET_RX_4G_MODE);
930		}
931
932		writel((u32)rpaddr, i2c->pdmabase + OFFSET_RX_MEM_ADDR);
933		writel(msgs->len, i2c->pdmabase + OFFSET_RX_LEN);
934	} else if (i2c->op == I2C_MASTER_WR) {
935		writel(I2C_DMA_INT_FLAG_NONE, i2c->pdmabase + OFFSET_INT_FLAG);
936		writel(I2C_DMA_CON_TX | dma_sync, i2c->pdmabase + OFFSET_CON);
937
938		dma_wr_buf = i2c_get_dma_safe_msg_buf(msgs, 1);
939		if (!dma_wr_buf)
940			return -ENOMEM;
941
942		wpaddr = dma_map_single(i2c->dev, dma_wr_buf,
943					msgs->len, DMA_TO_DEVICE);
944		if (dma_mapping_error(i2c->dev, wpaddr)) {
945			i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false);
946
947			return -ENOMEM;
948		}
949
950		if (i2c->dev_comp->max_dma_support > 32) {
951			reg_4g_mode = upper_32_bits(wpaddr);
952			writel(reg_4g_mode, i2c->pdmabase + OFFSET_TX_4G_MODE);
953		}
954
955		writel((u32)wpaddr, i2c->pdmabase + OFFSET_TX_MEM_ADDR);
956		writel(msgs->len, i2c->pdmabase + OFFSET_TX_LEN);
957	} else {
958		writel(I2C_DMA_CLR_FLAG, i2c->pdmabase + OFFSET_INT_FLAG);
959		writel(I2C_DMA_CLR_FLAG | dma_sync, i2c->pdmabase + OFFSET_CON);
960
961		dma_wr_buf = i2c_get_dma_safe_msg_buf(msgs, 1);
962		if (!dma_wr_buf)
963			return -ENOMEM;
964
965		wpaddr = dma_map_single(i2c->dev, dma_wr_buf,
966					msgs->len, DMA_TO_DEVICE);
967		if (dma_mapping_error(i2c->dev, wpaddr)) {
968			i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false);
969
970			return -ENOMEM;
971		}
972
973		dma_rd_buf = i2c_get_dma_safe_msg_buf((msgs + 1), 1);
974		if (!dma_rd_buf) {
975			dma_unmap_single(i2c->dev, wpaddr,
976					 msgs->len, DMA_TO_DEVICE);
977
978			i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false);
979
980			return -ENOMEM;
981		}
982
983		rpaddr = dma_map_single(i2c->dev, dma_rd_buf,
984					(msgs + 1)->len,
985					DMA_FROM_DEVICE);
986		if (dma_mapping_error(i2c->dev, rpaddr)) {
987			dma_unmap_single(i2c->dev, wpaddr,
988					 msgs->len, DMA_TO_DEVICE);
989
990			i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, false);
991			i2c_put_dma_safe_msg_buf(dma_rd_buf, (msgs + 1), false);
992
993			return -ENOMEM;
994		}
995
996		if (i2c->dev_comp->max_dma_support > 32) {
997			reg_4g_mode = upper_32_bits(wpaddr);
998			writel(reg_4g_mode, i2c->pdmabase + OFFSET_TX_4G_MODE);
999
1000			reg_4g_mode = upper_32_bits(rpaddr);
1001			writel(reg_4g_mode, i2c->pdmabase + OFFSET_RX_4G_MODE);
1002		}
1003
1004		writel((u32)wpaddr, i2c->pdmabase + OFFSET_TX_MEM_ADDR);
1005		writel((u32)rpaddr, i2c->pdmabase + OFFSET_RX_MEM_ADDR);
1006		writel(msgs->len, i2c->pdmabase + OFFSET_TX_LEN);
1007		writel((msgs + 1)->len, i2c->pdmabase + OFFSET_RX_LEN);
1008	}
1009
1010	writel(I2C_DMA_START_EN, i2c->pdmabase + OFFSET_EN);
1011
1012	if (!i2c->auto_restart) {
1013		start_reg = I2C_TRANSAC_START;
1014	} else {
1015		start_reg = I2C_TRANSAC_START | I2C_RS_MUL_TRIG;
1016		if (left_num >= 1)
1017			start_reg |= I2C_RS_MUL_CNFG;
1018	}
1019	mtk_i2c_writew(i2c, start_reg, OFFSET_START);
1020
1021	ret = wait_for_completion_timeout(&i2c->msg_complete,
1022					  i2c->adap.timeout);
1023
1024	/* Clear interrupt mask */
1025	mtk_i2c_writew(i2c, ~(restart_flag | I2C_HS_NACKERR | I2C_ACKERR |
1026			    I2C_ARB_LOST | I2C_TRANSAC_COMP), OFFSET_INTR_MASK);
1027
1028	if (i2c->op == I2C_MASTER_WR) {
1029		dma_unmap_single(i2c->dev, wpaddr,
1030				 msgs->len, DMA_TO_DEVICE);
1031
1032		i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, true);
1033	} else if (i2c->op == I2C_MASTER_RD) {
1034		dma_unmap_single(i2c->dev, rpaddr,
1035				 msgs->len, DMA_FROM_DEVICE);
1036
1037		i2c_put_dma_safe_msg_buf(dma_rd_buf, msgs, true);
1038	} else {
1039		dma_unmap_single(i2c->dev, wpaddr, msgs->len,
1040				 DMA_TO_DEVICE);
1041		dma_unmap_single(i2c->dev, rpaddr, (msgs + 1)->len,
1042				 DMA_FROM_DEVICE);
1043
1044		i2c_put_dma_safe_msg_buf(dma_wr_buf, msgs, true);
1045		i2c_put_dma_safe_msg_buf(dma_rd_buf, (msgs + 1), true);
1046	}
1047
1048	if (ret == 0) {
1049		dev_dbg(i2c->dev, "addr: %x, transfer timeout\n", msgs->addr);
1050		mtk_i2c_init_hw(i2c);
1051		return -ETIMEDOUT;
1052	}
1053
1054	if (i2c->irq_stat & (I2C_HS_NACKERR | I2C_ACKERR)) {
1055		dev_dbg(i2c->dev, "addr: %x, transfer ACK error\n", msgs->addr);
1056		mtk_i2c_init_hw(i2c);
1057		return -ENXIO;
1058	}
1059
1060	return 0;
1061}
1062
1063static int mtk_i2c_transfer(struct i2c_adapter *adap,
1064			    struct i2c_msg msgs[], int num)
1065{
1066	int ret;
1067	int left_num = num;
1068	struct mtk_i2c *i2c = i2c_get_adapdata(adap);
1069
1070	ret = mtk_i2c_clock_enable(i2c);
1071	if (ret)
1072		return ret;
1073
1074	i2c->auto_restart = i2c->dev_comp->auto_restart;
1075
1076	/* checking if we can skip restart and optimize using WRRD mode */
1077	if (i2c->auto_restart && num == 2) {
1078		if (!(msgs[0].flags & I2C_M_RD) && (msgs[1].flags & I2C_M_RD) &&
1079		    msgs[0].addr == msgs[1].addr) {
1080			i2c->auto_restart = 0;
1081		}
1082	}
1083
1084	if (i2c->auto_restart && num >= 2 &&
1085		i2c->speed_hz > I2C_MAX_FAST_MODE_PLUS_FREQ)
1086		/* ignore the first restart irq after the master code,
1087		 * otherwise the first transfer will be discarded.
1088		 */
1089		i2c->ignore_restart_irq = true;
1090	else
1091		i2c->ignore_restart_irq = false;
1092
1093	while (left_num--) {
1094		if (!msgs->buf) {
1095			dev_dbg(i2c->dev, "data buffer is NULL.\n");
1096			ret = -EINVAL;
1097			goto err_exit;
1098		}
1099
1100		if (msgs->flags & I2C_M_RD)
1101			i2c->op = I2C_MASTER_RD;
1102		else
1103			i2c->op = I2C_MASTER_WR;
1104
1105		if (!i2c->auto_restart) {
1106			if (num > 1) {
1107				/* combined two messages into one transaction */
1108				i2c->op = I2C_MASTER_WRRD;
1109				left_num--;
1110			}
1111		}
1112
1113		/* always use DMA mode. */
1114		ret = mtk_i2c_do_transfer(i2c, msgs, num, left_num);
1115		if (ret < 0)
1116			goto err_exit;
1117
1118		msgs++;
1119	}
1120	/* the return value is number of executed messages */
1121	ret = num;
1122
1123err_exit:
1124	mtk_i2c_clock_disable(i2c);
1125	return ret;
1126}
1127
1128static irqreturn_t mtk_i2c_irq(int irqno, void *dev_id)
1129{
1130	struct mtk_i2c *i2c = dev_id;
1131	u16 restart_flag = 0;
1132	u16 intr_stat;
1133
1134	if (i2c->auto_restart)
1135		restart_flag = I2C_RS_TRANSFER;
1136
1137	intr_stat = mtk_i2c_readw(i2c, OFFSET_INTR_STAT);
1138	mtk_i2c_writew(i2c, intr_stat, OFFSET_INTR_STAT);
1139
1140	/*
1141	 * when occurs ack error, i2c controller generate two interrupts
1142	 * first is the ack error interrupt, then the complete interrupt
1143	 * i2c->irq_stat need keep the two interrupt value.
1144	 */
1145	i2c->irq_stat |= intr_stat;
1146
1147	if (i2c->ignore_restart_irq && (i2c->irq_stat & restart_flag)) {
1148		i2c->ignore_restart_irq = false;
1149		i2c->irq_stat = 0;
1150		mtk_i2c_writew(i2c, I2C_RS_MUL_CNFG | I2C_RS_MUL_TRIG |
1151				    I2C_TRANSAC_START, OFFSET_START);
1152	} else {
1153		if (i2c->irq_stat & (I2C_TRANSAC_COMP | restart_flag))
1154			complete(&i2c->msg_complete);
1155	}
1156
1157	return IRQ_HANDLED;
1158}
1159
1160static u32 mtk_i2c_functionality(struct i2c_adapter *adap)
1161{
1162	if (i2c_check_quirks(adap, I2C_AQ_NO_ZERO_LEN))
1163		return I2C_FUNC_I2C |
1164			(I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
1165	else
1166		return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL;
1167}
1168
1169static const struct i2c_algorithm mtk_i2c_algorithm = {
1170	.master_xfer = mtk_i2c_transfer,
1171	.functionality = mtk_i2c_functionality,
1172};
1173
1174static int mtk_i2c_parse_dt(struct device_node *np, struct mtk_i2c *i2c)
1175{
1176	int ret;
1177
1178	ret = of_property_read_u32(np, "clock-frequency", &i2c->speed_hz);
1179	if (ret < 0)
1180		i2c->speed_hz = I2C_MAX_STANDARD_MODE_FREQ;
1181
1182	ret = of_property_read_u32(np, "clock-div", &i2c->clk_src_div);
1183	if (ret < 0)
1184		return ret;
1185
1186	if (i2c->clk_src_div == 0)
1187		return -EINVAL;
1188
1189	i2c->have_pmic = of_property_read_bool(np, "mediatek,have-pmic");
1190	i2c->use_push_pull =
1191		of_property_read_bool(np, "mediatek,use-push-pull");
1192
1193	return 0;
1194}
1195
1196static int mtk_i2c_probe(struct platform_device *pdev)
1197{
1198	int ret = 0;
1199	struct mtk_i2c *i2c;
1200	struct clk *clk;
1201	struct resource *res;
1202	int irq;
1203
1204	i2c = devm_kzalloc(&pdev->dev, sizeof(*i2c), GFP_KERNEL);
1205	if (!i2c)
1206		return -ENOMEM;
1207
1208	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1209	i2c->base = devm_ioremap_resource(&pdev->dev, res);
1210	if (IS_ERR(i2c->base))
1211		return PTR_ERR(i2c->base);
1212
1213	res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
1214	i2c->pdmabase = devm_ioremap_resource(&pdev->dev, res);
1215	if (IS_ERR(i2c->pdmabase))
1216		return PTR_ERR(i2c->pdmabase);
1217
1218	irq = platform_get_irq(pdev, 0);
1219	if (irq < 0)
1220		return irq;
1221
1222	init_completion(&i2c->msg_complete);
1223
1224	i2c->dev_comp = of_device_get_match_data(&pdev->dev);
1225	i2c->adap.dev.of_node = pdev->dev.of_node;
1226	i2c->dev = &pdev->dev;
1227	i2c->adap.dev.parent = &pdev->dev;
1228	i2c->adap.owner = THIS_MODULE;
1229	i2c->adap.algo = &mtk_i2c_algorithm;
1230	i2c->adap.quirks = i2c->dev_comp->quirks;
1231	i2c->adap.timeout = 2 * HZ;
1232	i2c->adap.retries = 1;
1233
1234	ret = mtk_i2c_parse_dt(pdev->dev.of_node, i2c);
1235	if (ret)
1236		return -EINVAL;
1237
1238	if (i2c->have_pmic && !i2c->dev_comp->pmic_i2c)
1239		return -EINVAL;
1240
1241	i2c->clk_main = devm_clk_get(&pdev->dev, "main");
1242	if (IS_ERR(i2c->clk_main)) {
1243		dev_err(&pdev->dev, "cannot get main clock\n");
1244		return PTR_ERR(i2c->clk_main);
1245	}
1246
1247	i2c->clk_dma = devm_clk_get(&pdev->dev, "dma");
1248	if (IS_ERR(i2c->clk_dma)) {
1249		dev_err(&pdev->dev, "cannot get dma clock\n");
1250		return PTR_ERR(i2c->clk_dma);
1251	}
1252
1253	i2c->clk_arb = devm_clk_get(&pdev->dev, "arb");
1254	if (IS_ERR(i2c->clk_arb))
1255		i2c->clk_arb = NULL;
1256
1257	clk = i2c->clk_main;
1258	if (i2c->have_pmic) {
1259		i2c->clk_pmic = devm_clk_get(&pdev->dev, "pmic");
1260		if (IS_ERR(i2c->clk_pmic)) {
1261			dev_err(&pdev->dev, "cannot get pmic clock\n");
1262			return PTR_ERR(i2c->clk_pmic);
1263		}
1264		clk = i2c->clk_pmic;
1265	}
1266
1267	strlcpy(i2c->adap.name, I2C_DRV_NAME, sizeof(i2c->adap.name));
1268
1269	ret = mtk_i2c_set_speed(i2c, clk_get_rate(clk));
1270	if (ret) {
1271		dev_err(&pdev->dev, "Failed to set the speed.\n");
1272		return -EINVAL;
1273	}
1274
1275	if (i2c->dev_comp->max_dma_support > 32) {
1276		ret = dma_set_mask(&pdev->dev,
1277				DMA_BIT_MASK(i2c->dev_comp->max_dma_support));
1278		if (ret) {
1279			dev_err(&pdev->dev, "dma_set_mask return error.\n");
1280			return ret;
1281		}
1282	}
1283
1284	ret = mtk_i2c_clock_enable(i2c);
1285	if (ret) {
1286		dev_err(&pdev->dev, "clock enable failed!\n");
1287		return ret;
1288	}
1289	mtk_i2c_init_hw(i2c);
1290	mtk_i2c_clock_disable(i2c);
1291
1292	ret = devm_request_irq(&pdev->dev, irq, mtk_i2c_irq,
1293			       IRQF_NO_SUSPEND | IRQF_TRIGGER_NONE,
1294			       I2C_DRV_NAME, i2c);
1295	if (ret < 0) {
1296		dev_err(&pdev->dev,
1297			"Request I2C IRQ %d fail\n", irq);
1298		return ret;
1299	}
1300
1301	i2c_set_adapdata(&i2c->adap, i2c);
1302	ret = i2c_add_adapter(&i2c->adap);
1303	if (ret)
1304		return ret;
1305
1306	platform_set_drvdata(pdev, i2c);
1307
1308	return 0;
1309}
1310
1311static int mtk_i2c_remove(struct platform_device *pdev)
1312{
1313	struct mtk_i2c *i2c = platform_get_drvdata(pdev);
1314
1315	i2c_del_adapter(&i2c->adap);
1316
1317	return 0;
1318}
1319
1320#ifdef CONFIG_PM_SLEEP
1321static int mtk_i2c_suspend_noirq(struct device *dev)
1322{
1323	struct mtk_i2c *i2c = dev_get_drvdata(dev);
1324
1325	i2c_mark_adapter_suspended(&i2c->adap);
1326
1327	return 0;
1328}
1329
1330static int mtk_i2c_resume_noirq(struct device *dev)
1331{
1332	int ret;
1333	struct mtk_i2c *i2c = dev_get_drvdata(dev);
1334
1335	ret = mtk_i2c_clock_enable(i2c);
1336	if (ret) {
1337		dev_err(dev, "clock enable failed!\n");
1338		return ret;
1339	}
1340
1341	mtk_i2c_init_hw(i2c);
1342
1343	mtk_i2c_clock_disable(i2c);
1344
1345	i2c_mark_adapter_resumed(&i2c->adap);
1346
1347	return 0;
1348}
1349#endif
1350
1351static const struct dev_pm_ops mtk_i2c_pm = {
1352	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(mtk_i2c_suspend_noirq,
1353				      mtk_i2c_resume_noirq)
1354};
1355
1356static struct platform_driver mtk_i2c_driver = {
1357	.probe = mtk_i2c_probe,
1358	.remove = mtk_i2c_remove,
1359	.driver = {
1360		.name = I2C_DRV_NAME,
1361		.pm = &mtk_i2c_pm,
1362		.of_match_table = of_match_ptr(mtk_i2c_of_match),
1363	},
1364};
1365
1366module_platform_driver(mtk_i2c_driver);
1367
1368MODULE_LICENSE("GPL v2");
1369MODULE_DESCRIPTION("MediaTek I2C Bus Driver");
1370MODULE_AUTHOR("Xudong Chen <xudong.chen@mediatek.com>");
1371