xref: /linux/drivers/i2c/busses/i2c-qcom-geni.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0
2 // Copyright (c) 2017-2018, The Linux Foundation. All rights reserved.
3 
4 #include <linux/acpi.h>
5 #include <linux/clk.h>
6 #include <linux/dmaengine.h>
7 #include <linux/dma-mapping.h>
8 #include <linux/dma/qcom-gpi-dma.h>
9 #include <linux/err.h>
10 #include <linux/i2c.h>
11 #include <linux/interrupt.h>
12 #include <linux/io.h>
13 #include <linux/module.h>
14 #include <linux/of.h>
15 #include <linux/platform_device.h>
16 #include <linux/pm_runtime.h>
17 #include <linux/soc/qcom/geni-se.h>
18 #include <linux/spinlock.h>
19 #include <linux/units.h>
20 
21 #define SE_I2C_TX_TRANS_LEN		0x26c
22 #define SE_I2C_RX_TRANS_LEN		0x270
23 #define SE_I2C_SCL_COUNTERS		0x278
24 
25 #define SE_I2C_ERR  (M_CMD_OVERRUN_EN | M_ILLEGAL_CMD_EN | M_CMD_FAILURE_EN |\
26 			M_GP_IRQ_1_EN | M_GP_IRQ_3_EN | M_GP_IRQ_4_EN)
27 #define SE_I2C_ABORT		BIT(1)
28 
29 /* M_CMD OP codes for I2C */
30 #define I2C_WRITE		0x1
31 #define I2C_READ		0x2
32 #define I2C_WRITE_READ		0x3
33 #define I2C_ADDR_ONLY		0x4
34 #define I2C_BUS_CLEAR		0x6
35 #define I2C_STOP_ON_BUS		0x7
36 /* M_CMD params for I2C */
37 #define PRE_CMD_DELAY		BIT(0)
38 #define TIMESTAMP_BEFORE	BIT(1)
39 #define STOP_STRETCH		BIT(2)
40 #define TIMESTAMP_AFTER		BIT(3)
41 #define POST_COMMAND_DELAY	BIT(4)
42 #define IGNORE_ADD_NACK		BIT(6)
43 #define READ_FINISHED_WITH_ACK	BIT(7)
44 #define BYPASS_ADDR_PHASE	BIT(8)
45 #define SLV_ADDR_MSK		GENMASK(15, 9)
46 #define SLV_ADDR_SHFT		9
47 /* I2C SCL COUNTER fields */
48 #define HIGH_COUNTER_MSK	GENMASK(29, 20)
49 #define HIGH_COUNTER_SHFT	20
50 #define LOW_COUNTER_MSK		GENMASK(19, 10)
51 #define LOW_COUNTER_SHFT	10
52 #define CYCLE_COUNTER_MSK	GENMASK(9, 0)
53 
54 #define I2C_PACK_TX		BIT(0)
55 #define I2C_PACK_RX		BIT(1)
56 
57 enum geni_i2c_err_code {
58 	GP_IRQ0,
59 	NACK,
60 	GP_IRQ2,
61 	BUS_PROTO,
62 	ARB_LOST,
63 	GP_IRQ5,
64 	GENI_OVERRUN,
65 	GENI_ILLEGAL_CMD,
66 	GENI_ABORT_DONE,
67 	GENI_TIMEOUT,
68 };
69 
70 #define DM_I2C_CB_ERR		((BIT(NACK) | BIT(BUS_PROTO) | BIT(ARB_LOST)) \
71 									<< 5)
72 
73 #define I2C_AUTO_SUSPEND_DELAY	250
74 #define KHZ(freq)		(1000 * freq)
75 #define PACKING_BYTES_PW	4
76 
77 #define ABORT_TIMEOUT		HZ
78 #define XFER_TIMEOUT		HZ
79 #define RST_TIMEOUT		HZ
80 
81 struct geni_i2c_dev {
82 	struct geni_se se;
83 	u32 tx_wm;
84 	int irq;
85 	int err;
86 	struct i2c_adapter adap;
87 	struct completion done;
88 	struct i2c_msg *cur;
89 	int cur_wr;
90 	int cur_rd;
91 	spinlock_t lock;
92 	struct clk *core_clk;
93 	u32 clk_freq_out;
94 	const struct geni_i2c_clk_fld *clk_fld;
95 	int suspended;
96 	void *dma_buf;
97 	size_t xfer_len;
98 	dma_addr_t dma_addr;
99 	struct dma_chan *tx_c;
100 	struct dma_chan *rx_c;
101 	bool gpi_mode;
102 	bool abort_done;
103 };
104 
105 struct geni_i2c_desc {
106 	bool has_core_clk;
107 	char *icc_ddr;
108 	bool no_dma_support;
109 	unsigned int tx_fifo_depth;
110 };
111 
112 struct geni_i2c_err_log {
113 	int err;
114 	const char *msg;
115 };
116 
117 static const struct geni_i2c_err_log gi2c_log[] = {
118 	[GP_IRQ0] = {-EIO, "Unknown I2C err GP_IRQ0"},
119 	[NACK] = {-ENXIO, "NACK: slv unresponsive, check its power/reset-ln"},
120 	[GP_IRQ2] = {-EIO, "Unknown I2C err GP IRQ2"},
121 	[BUS_PROTO] = {-EPROTO, "Bus proto err, noisy/unexpected start/stop"},
122 	[ARB_LOST] = {-EAGAIN, "Bus arbitration lost, clock line undriveable"},
123 	[GP_IRQ5] = {-EIO, "Unknown I2C err GP IRQ5"},
124 	[GENI_OVERRUN] = {-EIO, "Cmd overrun, check GENI cmd-state machine"},
125 	[GENI_ILLEGAL_CMD] = {-EIO, "Illegal cmd, check GENI cmd-state machine"},
126 	[GENI_ABORT_DONE] = {-ETIMEDOUT, "Abort after timeout successful"},
127 	[GENI_TIMEOUT] = {-ETIMEDOUT, "I2C TXN timed out"},
128 };
129 
130 struct geni_i2c_clk_fld {
131 	u32	clk_freq_out;
132 	u8	clk_div;
133 	u8	t_high_cnt;
134 	u8	t_low_cnt;
135 	u8	t_cycle_cnt;
136 };
137 
138 /*
139  * Hardware uses the underlying formula to calculate time periods of
140  * SCL clock cycle. Firmware uses some additional cycles excluded from the
141  * below formula and it is confirmed that the time periods are within
142  * specification limits.
143  *
144  * time of high period of SCL: t_high = (t_high_cnt * clk_div) / source_clock
145  * time of low period of SCL: t_low = (t_low_cnt * clk_div) / source_clock
146  * time of full period of SCL: t_cycle = (t_cycle_cnt * clk_div) / source_clock
147  * clk_freq_out = t / t_cycle
148  * source_clock = 19.2 MHz
149  */
150 static const struct geni_i2c_clk_fld geni_i2c_clk_map_19p2mhz[] = {
151 	{KHZ(100), 7, 10, 11, 26},
152 	{KHZ(400), 2,  5, 12, 24},
153 	{KHZ(1000), 1, 3,  9, 18},
154 	{},
155 };
156 
157 /* source_clock = 32 MHz */
158 static const struct geni_i2c_clk_fld geni_i2c_clk_map_32mhz[] = {
159 	{KHZ(100), 8, 14, 18, 40},
160 	{KHZ(400), 4,  3, 11, 20},
161 	{KHZ(1000), 2, 3,  6, 15},
162 	{},
163 };
164 
165 static int geni_i2c_clk_map_idx(struct geni_i2c_dev *gi2c)
166 {
167 	const struct geni_i2c_clk_fld *itr;
168 
169 	if (clk_get_rate(gi2c->se.clk) == 32 * HZ_PER_MHZ)
170 		itr = geni_i2c_clk_map_32mhz;
171 	else
172 		itr = geni_i2c_clk_map_19p2mhz;
173 
174 	while (itr->clk_freq_out != 0) {
175 		if (itr->clk_freq_out == gi2c->clk_freq_out) {
176 			gi2c->clk_fld = itr;
177 			return 0;
178 		}
179 		itr++;
180 	}
181 	return -EINVAL;
182 }
183 
184 static void qcom_geni_i2c_conf(struct geni_i2c_dev *gi2c)
185 {
186 	const struct geni_i2c_clk_fld *itr = gi2c->clk_fld;
187 	u32 val;
188 
189 	writel_relaxed(0, gi2c->se.base + SE_GENI_CLK_SEL);
190 
191 	val = (itr->clk_div << CLK_DIV_SHFT) | SER_CLK_EN;
192 	writel_relaxed(val, gi2c->se.base + GENI_SER_M_CLK_CFG);
193 
194 	val = itr->t_high_cnt << HIGH_COUNTER_SHFT;
195 	val |= itr->t_low_cnt << LOW_COUNTER_SHFT;
196 	val |= itr->t_cycle_cnt;
197 	writel_relaxed(val, gi2c->se.base + SE_I2C_SCL_COUNTERS);
198 }
199 
200 static void geni_i2c_err_misc(struct geni_i2c_dev *gi2c)
201 {
202 	u32 m_cmd = readl_relaxed(gi2c->se.base + SE_GENI_M_CMD0);
203 	u32 m_stat = readl_relaxed(gi2c->se.base + SE_GENI_M_IRQ_STATUS);
204 	u32 geni_s = readl_relaxed(gi2c->se.base + SE_GENI_STATUS);
205 	u32 geni_ios = readl_relaxed(gi2c->se.base + SE_GENI_IOS);
206 	u32 dma = readl_relaxed(gi2c->se.base + SE_GENI_DMA_MODE_EN);
207 	u32 rx_st, tx_st;
208 
209 	if (dma) {
210 		rx_st = readl_relaxed(gi2c->se.base + SE_DMA_RX_IRQ_STAT);
211 		tx_st = readl_relaxed(gi2c->se.base + SE_DMA_TX_IRQ_STAT);
212 	} else {
213 		rx_st = readl_relaxed(gi2c->se.base + SE_GENI_RX_FIFO_STATUS);
214 		tx_st = readl_relaxed(gi2c->se.base + SE_GENI_TX_FIFO_STATUS);
215 	}
216 	dev_dbg(gi2c->se.dev, "DMA:%d tx_stat:0x%x, rx_stat:0x%x, irq-stat:0x%x\n",
217 		dma, tx_st, rx_st, m_stat);
218 	dev_dbg(gi2c->se.dev, "m_cmd:0x%x, geni_status:0x%x, geni_ios:0x%x\n",
219 		m_cmd, geni_s, geni_ios);
220 }
221 
222 static void geni_i2c_err(struct geni_i2c_dev *gi2c, int err)
223 {
224 	if (!gi2c->err)
225 		gi2c->err = gi2c_log[err].err;
226 	if (gi2c->cur)
227 		dev_dbg(gi2c->se.dev, "len:%d, slv-addr:0x%x, RD/WR:%d\n",
228 			gi2c->cur->len, gi2c->cur->addr, gi2c->cur->flags);
229 
230 	switch (err) {
231 	case GENI_ABORT_DONE:
232 		gi2c->abort_done = true;
233 		break;
234 	case NACK:
235 	case GENI_TIMEOUT:
236 		dev_dbg(gi2c->se.dev, "%s\n", gi2c_log[err].msg);
237 		break;
238 	default:
239 		dev_err(gi2c->se.dev, "%s\n", gi2c_log[err].msg);
240 		geni_i2c_err_misc(gi2c);
241 		break;
242 	}
243 }
244 
245 static irqreturn_t geni_i2c_irq(int irq, void *dev)
246 {
247 	struct geni_i2c_dev *gi2c = dev;
248 	void __iomem *base = gi2c->se.base;
249 	int j, p;
250 	u32 m_stat;
251 	u32 rx_st;
252 	u32 dm_tx_st;
253 	u32 dm_rx_st;
254 	u32 dma;
255 	u32 val;
256 	struct i2c_msg *cur;
257 
258 	spin_lock(&gi2c->lock);
259 	m_stat = readl_relaxed(base + SE_GENI_M_IRQ_STATUS);
260 	rx_st = readl_relaxed(base + SE_GENI_RX_FIFO_STATUS);
261 	dm_tx_st = readl_relaxed(base + SE_DMA_TX_IRQ_STAT);
262 	dm_rx_st = readl_relaxed(base + SE_DMA_RX_IRQ_STAT);
263 	dma = readl_relaxed(base + SE_GENI_DMA_MODE_EN);
264 	cur = gi2c->cur;
265 
266 	if (!cur ||
267 	    m_stat & (M_CMD_FAILURE_EN | M_CMD_ABORT_EN) ||
268 	    dm_rx_st & (DM_I2C_CB_ERR)) {
269 		if (m_stat & M_GP_IRQ_1_EN)
270 			geni_i2c_err(gi2c, NACK);
271 		if (m_stat & M_GP_IRQ_3_EN)
272 			geni_i2c_err(gi2c, BUS_PROTO);
273 		if (m_stat & M_GP_IRQ_4_EN)
274 			geni_i2c_err(gi2c, ARB_LOST);
275 		if (m_stat & M_CMD_OVERRUN_EN)
276 			geni_i2c_err(gi2c, GENI_OVERRUN);
277 		if (m_stat & M_ILLEGAL_CMD_EN)
278 			geni_i2c_err(gi2c, GENI_ILLEGAL_CMD);
279 		if (m_stat & M_CMD_ABORT_EN)
280 			geni_i2c_err(gi2c, GENI_ABORT_DONE);
281 		if (m_stat & M_GP_IRQ_0_EN)
282 			geni_i2c_err(gi2c, GP_IRQ0);
283 
284 		/* Disable the TX Watermark interrupt to stop TX */
285 		if (!dma)
286 			writel_relaxed(0, base + SE_GENI_TX_WATERMARK_REG);
287 	} else if (dma) {
288 		dev_dbg(gi2c->se.dev, "i2c dma tx:0x%x, dma rx:0x%x\n",
289 			dm_tx_st, dm_rx_st);
290 	} else if (cur->flags & I2C_M_RD &&
291 		   m_stat & (M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN)) {
292 		u32 rxcnt = rx_st & RX_FIFO_WC_MSK;
293 
294 		for (j = 0; j < rxcnt; j++) {
295 			p = 0;
296 			val = readl_relaxed(base + SE_GENI_RX_FIFOn);
297 			while (gi2c->cur_rd < cur->len && p < sizeof(val)) {
298 				cur->buf[gi2c->cur_rd++] = val & 0xff;
299 				val >>= 8;
300 				p++;
301 			}
302 			if (gi2c->cur_rd == cur->len)
303 				break;
304 		}
305 	} else if (!(cur->flags & I2C_M_RD) &&
306 		   m_stat & M_TX_FIFO_WATERMARK_EN) {
307 		for (j = 0; j < gi2c->tx_wm; j++) {
308 			u32 temp;
309 
310 			val = 0;
311 			p = 0;
312 			while (gi2c->cur_wr < cur->len && p < sizeof(val)) {
313 				temp = cur->buf[gi2c->cur_wr++];
314 				val |= temp << (p * 8);
315 				p++;
316 			}
317 			writel_relaxed(val, base + SE_GENI_TX_FIFOn);
318 			/* TX Complete, Disable the TX Watermark interrupt */
319 			if (gi2c->cur_wr == cur->len) {
320 				writel_relaxed(0, base + SE_GENI_TX_WATERMARK_REG);
321 				break;
322 			}
323 		}
324 	}
325 
326 	if (m_stat)
327 		writel_relaxed(m_stat, base + SE_GENI_M_IRQ_CLEAR);
328 
329 	if (dma && dm_tx_st)
330 		writel_relaxed(dm_tx_st, base + SE_DMA_TX_IRQ_CLR);
331 	if (dma && dm_rx_st)
332 		writel_relaxed(dm_rx_st, base + SE_DMA_RX_IRQ_CLR);
333 
334 	/* if this is err with done-bit not set, handle that through timeout. */
335 	if (m_stat & M_CMD_DONE_EN || m_stat & M_CMD_ABORT_EN ||
336 	    dm_tx_st & TX_DMA_DONE || dm_tx_st & TX_RESET_DONE ||
337 	    dm_rx_st & RX_DMA_DONE || dm_rx_st & RX_RESET_DONE)
338 		complete(&gi2c->done);
339 
340 	spin_unlock(&gi2c->lock);
341 
342 	return IRQ_HANDLED;
343 }
344 
345 static void geni_i2c_abort_xfer(struct geni_i2c_dev *gi2c)
346 {
347 	unsigned long time_left = ABORT_TIMEOUT;
348 	unsigned long flags;
349 
350 	spin_lock_irqsave(&gi2c->lock, flags);
351 	geni_i2c_err(gi2c, GENI_TIMEOUT);
352 	gi2c->cur = NULL;
353 	gi2c->abort_done = false;
354 	geni_se_abort_m_cmd(&gi2c->se);
355 	spin_unlock_irqrestore(&gi2c->lock, flags);
356 
357 	do {
358 		time_left = wait_for_completion_timeout(&gi2c->done, time_left);
359 	} while (!gi2c->abort_done && time_left);
360 
361 	if (!time_left)
362 		dev_err(gi2c->se.dev, "Timeout abort_m_cmd\n");
363 }
364 
365 static void geni_i2c_rx_fsm_rst(struct geni_i2c_dev *gi2c)
366 {
367 	u32 val;
368 	unsigned long time_left = RST_TIMEOUT;
369 
370 	writel_relaxed(1, gi2c->se.base + SE_DMA_RX_FSM_RST);
371 	do {
372 		time_left = wait_for_completion_timeout(&gi2c->done, time_left);
373 		val = readl_relaxed(gi2c->se.base + SE_DMA_RX_IRQ_STAT);
374 	} while (!(val & RX_RESET_DONE) && time_left);
375 
376 	if (!(val & RX_RESET_DONE))
377 		dev_err(gi2c->se.dev, "Timeout resetting RX_FSM\n");
378 }
379 
380 static void geni_i2c_tx_fsm_rst(struct geni_i2c_dev *gi2c)
381 {
382 	u32 val;
383 	unsigned long time_left = RST_TIMEOUT;
384 
385 	writel_relaxed(1, gi2c->se.base + SE_DMA_TX_FSM_RST);
386 	do {
387 		time_left = wait_for_completion_timeout(&gi2c->done, time_left);
388 		val = readl_relaxed(gi2c->se.base + SE_DMA_TX_IRQ_STAT);
389 	} while (!(val & TX_RESET_DONE) && time_left);
390 
391 	if (!(val & TX_RESET_DONE))
392 		dev_err(gi2c->se.dev, "Timeout resetting TX_FSM\n");
393 }
394 
395 static void geni_i2c_rx_msg_cleanup(struct geni_i2c_dev *gi2c,
396 				     struct i2c_msg *cur)
397 {
398 	gi2c->cur_rd = 0;
399 	if (gi2c->dma_buf) {
400 		if (gi2c->err)
401 			geni_i2c_rx_fsm_rst(gi2c);
402 		geni_se_rx_dma_unprep(&gi2c->se, gi2c->dma_addr, gi2c->xfer_len);
403 		i2c_put_dma_safe_msg_buf(gi2c->dma_buf, cur, !gi2c->err);
404 	}
405 }
406 
407 static void geni_i2c_tx_msg_cleanup(struct geni_i2c_dev *gi2c,
408 				     struct i2c_msg *cur)
409 {
410 	gi2c->cur_wr = 0;
411 	if (gi2c->dma_buf) {
412 		if (gi2c->err)
413 			geni_i2c_tx_fsm_rst(gi2c);
414 		geni_se_tx_dma_unprep(&gi2c->se, gi2c->dma_addr, gi2c->xfer_len);
415 		i2c_put_dma_safe_msg_buf(gi2c->dma_buf, cur, !gi2c->err);
416 	}
417 }
418 
419 static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
420 				u32 m_param)
421 {
422 	dma_addr_t rx_dma = 0;
423 	unsigned long time_left;
424 	void *dma_buf;
425 	struct geni_se *se = &gi2c->se;
426 	size_t len = msg->len;
427 	struct i2c_msg *cur;
428 
429 	dma_buf = i2c_get_dma_safe_msg_buf(msg, 32);
430 	if (dma_buf)
431 		geni_se_select_mode(se, GENI_SE_DMA);
432 	else
433 		geni_se_select_mode(se, GENI_SE_FIFO);
434 
435 	writel_relaxed(len, se->base + SE_I2C_RX_TRANS_LEN);
436 	geni_se_setup_m_cmd(se, I2C_READ, m_param);
437 
438 	if (dma_buf && geni_se_rx_dma_prep(se, dma_buf, len, &rx_dma)) {
439 		geni_se_select_mode(se, GENI_SE_FIFO);
440 		i2c_put_dma_safe_msg_buf(dma_buf, msg, false);
441 		dma_buf = NULL;
442 	} else {
443 		gi2c->xfer_len = len;
444 		gi2c->dma_addr = rx_dma;
445 		gi2c->dma_buf = dma_buf;
446 	}
447 
448 	cur = gi2c->cur;
449 	time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT);
450 	if (!time_left)
451 		geni_i2c_abort_xfer(gi2c);
452 
453 	geni_i2c_rx_msg_cleanup(gi2c, cur);
454 
455 	return gi2c->err;
456 }
457 
458 static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
459 				u32 m_param)
460 {
461 	dma_addr_t tx_dma = 0;
462 	unsigned long time_left;
463 	void *dma_buf;
464 	struct geni_se *se = &gi2c->se;
465 	size_t len = msg->len;
466 	struct i2c_msg *cur;
467 
468 	dma_buf = i2c_get_dma_safe_msg_buf(msg, 32);
469 	if (dma_buf)
470 		geni_se_select_mode(se, GENI_SE_DMA);
471 	else
472 		geni_se_select_mode(se, GENI_SE_FIFO);
473 
474 	writel_relaxed(len, se->base + SE_I2C_TX_TRANS_LEN);
475 	geni_se_setup_m_cmd(se, I2C_WRITE, m_param);
476 
477 	if (dma_buf && geni_se_tx_dma_prep(se, dma_buf, len, &tx_dma)) {
478 		geni_se_select_mode(se, GENI_SE_FIFO);
479 		i2c_put_dma_safe_msg_buf(dma_buf, msg, false);
480 		dma_buf = NULL;
481 	} else {
482 		gi2c->xfer_len = len;
483 		gi2c->dma_addr = tx_dma;
484 		gi2c->dma_buf = dma_buf;
485 	}
486 
487 	if (!dma_buf) /* Get FIFO IRQ */
488 		writel_relaxed(1, se->base + SE_GENI_TX_WATERMARK_REG);
489 
490 	cur = gi2c->cur;
491 	time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT);
492 	if (!time_left)
493 		geni_i2c_abort_xfer(gi2c);
494 
495 	geni_i2c_tx_msg_cleanup(gi2c, cur);
496 
497 	return gi2c->err;
498 }
499 
500 static void i2c_gpi_cb_result(void *cb, const struct dmaengine_result *result)
501 {
502 	struct geni_i2c_dev *gi2c = cb;
503 
504 	if (result->result != DMA_TRANS_NOERROR) {
505 		dev_err(gi2c->se.dev, "DMA txn failed:%d\n", result->result);
506 		gi2c->err = -EIO;
507 	} else if (result->residue) {
508 		dev_dbg(gi2c->se.dev, "DMA xfer has pending: %d\n", result->residue);
509 	}
510 
511 	complete(&gi2c->done);
512 }
513 
514 static void geni_i2c_gpi_unmap(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
515 			       void *tx_buf, dma_addr_t tx_addr,
516 			       void *rx_buf, dma_addr_t rx_addr)
517 {
518 	if (tx_buf) {
519 		dma_unmap_single(gi2c->se.dev->parent, tx_addr, msg->len, DMA_TO_DEVICE);
520 		i2c_put_dma_safe_msg_buf(tx_buf, msg, !gi2c->err);
521 	}
522 
523 	if (rx_buf) {
524 		dma_unmap_single(gi2c->se.dev->parent, rx_addr, msg->len, DMA_FROM_DEVICE);
525 		i2c_put_dma_safe_msg_buf(rx_buf, msg, !gi2c->err);
526 	}
527 }
528 
529 static int geni_i2c_gpi(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
530 			struct dma_slave_config *config, dma_addr_t *dma_addr_p,
531 			void **buf, unsigned int op, struct dma_chan *dma_chan)
532 {
533 	struct gpi_i2c_config *peripheral;
534 	unsigned int flags;
535 	void *dma_buf;
536 	dma_addr_t addr;
537 	enum dma_data_direction map_dirn;
538 	enum dma_transfer_direction dma_dirn;
539 	struct dma_async_tx_descriptor *desc;
540 	int ret;
541 
542 	peripheral = config->peripheral_config;
543 
544 	dma_buf = i2c_get_dma_safe_msg_buf(msg, 1);
545 	if (!dma_buf)
546 		return -ENOMEM;
547 
548 	if (op == I2C_WRITE)
549 		map_dirn = DMA_TO_DEVICE;
550 	else
551 		map_dirn = DMA_FROM_DEVICE;
552 
553 	addr = dma_map_single(gi2c->se.dev->parent, dma_buf, msg->len, map_dirn);
554 	if (dma_mapping_error(gi2c->se.dev->parent, addr)) {
555 		i2c_put_dma_safe_msg_buf(dma_buf, msg, false);
556 		return -ENOMEM;
557 	}
558 
559 	/* set the length as message for rx txn */
560 	peripheral->rx_len = msg->len;
561 	peripheral->op = op;
562 
563 	ret = dmaengine_slave_config(dma_chan, config);
564 	if (ret) {
565 		dev_err(gi2c->se.dev, "dma config error: %d for op:%d\n", ret, op);
566 		goto err_config;
567 	}
568 
569 	peripheral->set_config = 0;
570 	peripheral->multi_msg = true;
571 	flags = DMA_PREP_INTERRUPT | DMA_CTRL_ACK;
572 
573 	if (op == I2C_WRITE)
574 		dma_dirn = DMA_MEM_TO_DEV;
575 	else
576 		dma_dirn = DMA_DEV_TO_MEM;
577 
578 	desc = dmaengine_prep_slave_single(dma_chan, addr, msg->len, dma_dirn, flags);
579 	if (!desc) {
580 		dev_err(gi2c->se.dev, "prep_slave_sg failed\n");
581 		ret = -EIO;
582 		goto err_config;
583 	}
584 
585 	desc->callback_result = i2c_gpi_cb_result;
586 	desc->callback_param = gi2c;
587 
588 	dmaengine_submit(desc);
589 	*buf = dma_buf;
590 	*dma_addr_p = addr;
591 
592 	return 0;
593 
594 err_config:
595 	dma_unmap_single(gi2c->se.dev->parent, addr, msg->len, map_dirn);
596 	i2c_put_dma_safe_msg_buf(dma_buf, msg, false);
597 	return ret;
598 }
599 
600 static int geni_i2c_gpi_xfer(struct geni_i2c_dev *gi2c, struct i2c_msg msgs[], int num)
601 {
602 	struct dma_slave_config config = {};
603 	struct gpi_i2c_config peripheral = {};
604 	int i, ret = 0;
605 	unsigned long time_left;
606 	dma_addr_t tx_addr, rx_addr;
607 	void *tx_buf = NULL, *rx_buf = NULL;
608 	const struct geni_i2c_clk_fld *itr = gi2c->clk_fld;
609 
610 	config.peripheral_config = &peripheral;
611 	config.peripheral_size = sizeof(peripheral);
612 
613 	peripheral.pack_enable = I2C_PACK_TX | I2C_PACK_RX;
614 	peripheral.cycle_count = itr->t_cycle_cnt;
615 	peripheral.high_count = itr->t_high_cnt;
616 	peripheral.low_count = itr->t_low_cnt;
617 	peripheral.clk_div = itr->clk_div;
618 	peripheral.set_config = 1;
619 	peripheral.multi_msg = false;
620 
621 	for (i = 0; i < num; i++) {
622 		gi2c->cur = &msgs[i];
623 		gi2c->err = 0;
624 		dev_dbg(gi2c->se.dev, "msg[%d].len:%d\n", i, gi2c->cur->len);
625 
626 		peripheral.stretch = 0;
627 		if (i < num - 1)
628 			peripheral.stretch = 1;
629 
630 		peripheral.addr = msgs[i].addr;
631 
632 		ret =  geni_i2c_gpi(gi2c, &msgs[i], &config,
633 				    &tx_addr, &tx_buf, I2C_WRITE, gi2c->tx_c);
634 		if (ret)
635 			goto err;
636 
637 		if (msgs[i].flags & I2C_M_RD) {
638 			ret =  geni_i2c_gpi(gi2c, &msgs[i], &config,
639 					    &rx_addr, &rx_buf, I2C_READ, gi2c->rx_c);
640 			if (ret)
641 				goto err;
642 
643 			dma_async_issue_pending(gi2c->rx_c);
644 		}
645 
646 		dma_async_issue_pending(gi2c->tx_c);
647 
648 		time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT);
649 		if (!time_left)
650 			gi2c->err = -ETIMEDOUT;
651 
652 		if (gi2c->err) {
653 			ret = gi2c->err;
654 			goto err;
655 		}
656 
657 		geni_i2c_gpi_unmap(gi2c, &msgs[i], tx_buf, tx_addr, rx_buf, rx_addr);
658 	}
659 
660 	return num;
661 
662 err:
663 	dev_err(gi2c->se.dev, "GPI transfer failed: %d\n", ret);
664 	dmaengine_terminate_sync(gi2c->rx_c);
665 	dmaengine_terminate_sync(gi2c->tx_c);
666 	geni_i2c_gpi_unmap(gi2c, &msgs[i], tx_buf, tx_addr, rx_buf, rx_addr);
667 	return ret;
668 }
669 
670 static int geni_i2c_fifo_xfer(struct geni_i2c_dev *gi2c,
671 			      struct i2c_msg msgs[], int num)
672 {
673 	int i, ret = 0;
674 
675 	for (i = 0; i < num; i++) {
676 		u32 m_param = i < (num - 1) ? STOP_STRETCH : 0;
677 
678 		m_param |= ((msgs[i].addr << SLV_ADDR_SHFT) & SLV_ADDR_MSK);
679 
680 		gi2c->cur = &msgs[i];
681 		if (msgs[i].flags & I2C_M_RD)
682 			ret = geni_i2c_rx_one_msg(gi2c, &msgs[i], m_param);
683 		else
684 			ret = geni_i2c_tx_one_msg(gi2c, &msgs[i], m_param);
685 
686 		if (ret)
687 			return ret;
688 	}
689 
690 	return num;
691 }
692 
693 static int geni_i2c_xfer(struct i2c_adapter *adap,
694 			 struct i2c_msg msgs[],
695 			 int num)
696 {
697 	struct geni_i2c_dev *gi2c = i2c_get_adapdata(adap);
698 	int ret;
699 
700 	gi2c->err = 0;
701 	reinit_completion(&gi2c->done);
702 	ret = pm_runtime_get_sync(gi2c->se.dev);
703 	if (ret < 0) {
704 		dev_err(gi2c->se.dev, "error turning SE resources:%d\n", ret);
705 		pm_runtime_put_noidle(gi2c->se.dev);
706 		/* Set device in suspended since resume failed */
707 		pm_runtime_set_suspended(gi2c->se.dev);
708 		return ret;
709 	}
710 
711 	qcom_geni_i2c_conf(gi2c);
712 
713 	if (gi2c->gpi_mode)
714 		ret = geni_i2c_gpi_xfer(gi2c, msgs, num);
715 	else
716 		ret = geni_i2c_fifo_xfer(gi2c, msgs, num);
717 
718 	pm_runtime_mark_last_busy(gi2c->se.dev);
719 	pm_runtime_put_autosuspend(gi2c->se.dev);
720 	gi2c->cur = NULL;
721 	gi2c->err = 0;
722 	return ret;
723 }
724 
725 static u32 geni_i2c_func(struct i2c_adapter *adap)
726 {
727 	return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
728 }
729 
730 static const struct i2c_algorithm geni_i2c_algo = {
731 	.master_xfer	= geni_i2c_xfer,
732 	.functionality	= geni_i2c_func,
733 };
734 
735 #ifdef CONFIG_ACPI
736 static const struct acpi_device_id geni_i2c_acpi_match[] = {
737 	{ "QCOM0220"},
738 	{ "QCOM0411" },
739 	{ }
740 };
741 MODULE_DEVICE_TABLE(acpi, geni_i2c_acpi_match);
742 #endif
743 
744 static void release_gpi_dma(struct geni_i2c_dev *gi2c)
745 {
746 	if (gi2c->rx_c)
747 		dma_release_channel(gi2c->rx_c);
748 
749 	if (gi2c->tx_c)
750 		dma_release_channel(gi2c->tx_c);
751 }
752 
753 static int setup_gpi_dma(struct geni_i2c_dev *gi2c)
754 {
755 	int ret;
756 
757 	geni_se_select_mode(&gi2c->se, GENI_GPI_DMA);
758 	gi2c->tx_c = dma_request_chan(gi2c->se.dev, "tx");
759 	if (IS_ERR(gi2c->tx_c)) {
760 		ret = dev_err_probe(gi2c->se.dev, PTR_ERR(gi2c->tx_c),
761 				    "Failed to get tx DMA ch\n");
762 		goto err_tx;
763 	}
764 
765 	gi2c->rx_c = dma_request_chan(gi2c->se.dev, "rx");
766 	if (IS_ERR(gi2c->rx_c)) {
767 		ret = dev_err_probe(gi2c->se.dev, PTR_ERR(gi2c->rx_c),
768 				    "Failed to get rx DMA ch\n");
769 		goto err_rx;
770 	}
771 
772 	dev_dbg(gi2c->se.dev, "Grabbed GPI dma channels\n");
773 	return 0;
774 
775 err_rx:
776 	dma_release_channel(gi2c->tx_c);
777 err_tx:
778 	return ret;
779 }
780 
781 static int geni_i2c_probe(struct platform_device *pdev)
782 {
783 	struct geni_i2c_dev *gi2c;
784 	u32 proto, tx_depth, fifo_disable;
785 	int ret;
786 	struct device *dev = &pdev->dev;
787 	const struct geni_i2c_desc *desc = NULL;
788 
789 	gi2c = devm_kzalloc(dev, sizeof(*gi2c), GFP_KERNEL);
790 	if (!gi2c)
791 		return -ENOMEM;
792 
793 	gi2c->se.dev = dev;
794 	gi2c->se.wrapper = dev_get_drvdata(dev->parent);
795 	gi2c->se.base = devm_platform_ioremap_resource(pdev, 0);
796 	if (IS_ERR(gi2c->se.base))
797 		return PTR_ERR(gi2c->se.base);
798 
799 	desc = device_get_match_data(&pdev->dev);
800 
801 	if (desc && desc->has_core_clk) {
802 		gi2c->core_clk = devm_clk_get(dev, "core");
803 		if (IS_ERR(gi2c->core_clk))
804 			return PTR_ERR(gi2c->core_clk);
805 	}
806 
807 	gi2c->se.clk = devm_clk_get(dev, "se");
808 	if (IS_ERR(gi2c->se.clk) && !has_acpi_companion(dev))
809 		return PTR_ERR(gi2c->se.clk);
810 
811 	ret = device_property_read_u32(dev, "clock-frequency",
812 				       &gi2c->clk_freq_out);
813 	if (ret) {
814 		dev_info(dev, "Bus frequency not specified, default to 100kHz.\n");
815 		gi2c->clk_freq_out = KHZ(100);
816 	}
817 
818 	if (has_acpi_companion(dev))
819 		ACPI_COMPANION_SET(&gi2c->adap.dev, ACPI_COMPANION(dev));
820 
821 	gi2c->irq = platform_get_irq(pdev, 0);
822 	if (gi2c->irq < 0)
823 		return gi2c->irq;
824 
825 	ret = geni_i2c_clk_map_idx(gi2c);
826 	if (ret) {
827 		dev_err(dev, "Invalid clk frequency %d Hz: %d\n",
828 			gi2c->clk_freq_out, ret);
829 		return ret;
830 	}
831 
832 	gi2c->adap.algo = &geni_i2c_algo;
833 	init_completion(&gi2c->done);
834 	spin_lock_init(&gi2c->lock);
835 	platform_set_drvdata(pdev, gi2c);
836 
837 	/* Keep interrupts disabled initially to allow for low-power modes */
838 	ret = devm_request_irq(dev, gi2c->irq, geni_i2c_irq, IRQF_NO_AUTOEN,
839 			       dev_name(dev), gi2c);
840 	if (ret) {
841 		dev_err(dev, "Request_irq failed:%d: err:%d\n",
842 			gi2c->irq, ret);
843 		return ret;
844 	}
845 	i2c_set_adapdata(&gi2c->adap, gi2c);
846 	gi2c->adap.dev.parent = dev;
847 	gi2c->adap.dev.of_node = dev->of_node;
848 	strscpy(gi2c->adap.name, "Geni-I2C", sizeof(gi2c->adap.name));
849 
850 	ret = geni_icc_get(&gi2c->se, desc ? desc->icc_ddr : "qup-memory");
851 	if (ret)
852 		return ret;
853 	/*
854 	 * Set the bus quota for core and cpu to a reasonable value for
855 	 * register access.
856 	 * Set quota for DDR based on bus speed.
857 	 */
858 	gi2c->se.icc_paths[GENI_TO_CORE].avg_bw = GENI_DEFAULT_BW;
859 	gi2c->se.icc_paths[CPU_TO_GENI].avg_bw = GENI_DEFAULT_BW;
860 	if (!desc || desc->icc_ddr)
861 		gi2c->se.icc_paths[GENI_TO_DDR].avg_bw = Bps_to_icc(gi2c->clk_freq_out);
862 
863 	ret = geni_icc_set_bw(&gi2c->se);
864 	if (ret)
865 		return ret;
866 
867 	ret = clk_prepare_enable(gi2c->core_clk);
868 	if (ret)
869 		return ret;
870 
871 	ret = geni_se_resources_on(&gi2c->se);
872 	if (ret) {
873 		dev_err(dev, "Error turning on resources %d\n", ret);
874 		clk_disable_unprepare(gi2c->core_clk);
875 		return ret;
876 	}
877 	proto = geni_se_read_proto(&gi2c->se);
878 	if (proto != GENI_SE_I2C) {
879 		dev_err(dev, "Invalid proto %d\n", proto);
880 		geni_se_resources_off(&gi2c->se);
881 		clk_disable_unprepare(gi2c->core_clk);
882 		return -ENXIO;
883 	}
884 
885 	if (desc && desc->no_dma_support)
886 		fifo_disable = false;
887 	else
888 		fifo_disable = readl_relaxed(gi2c->se.base + GENI_IF_DISABLE_RO) & FIFO_IF_DISABLE;
889 
890 	if (fifo_disable) {
891 		/* FIFO is disabled, so we can only use GPI DMA */
892 		gi2c->gpi_mode = true;
893 		ret = setup_gpi_dma(gi2c);
894 		if (ret) {
895 			geni_se_resources_off(&gi2c->se);
896 			clk_disable_unprepare(gi2c->core_clk);
897 			return dev_err_probe(dev, ret, "Failed to setup GPI DMA mode\n");
898 		}
899 
900 		dev_dbg(dev, "Using GPI DMA mode for I2C\n");
901 	} else {
902 		gi2c->gpi_mode = false;
903 		tx_depth = geni_se_get_tx_fifo_depth(&gi2c->se);
904 
905 		/* I2C Master Hub Serial Elements doesn't have the HW_PARAM_0 register */
906 		if (!tx_depth && desc)
907 			tx_depth = desc->tx_fifo_depth;
908 
909 		if (!tx_depth) {
910 			dev_err(dev, "Invalid TX FIFO depth\n");
911 			geni_se_resources_off(&gi2c->se);
912 			clk_disable_unprepare(gi2c->core_clk);
913 			return -EINVAL;
914 		}
915 
916 		gi2c->tx_wm = tx_depth - 1;
917 		geni_se_init(&gi2c->se, gi2c->tx_wm, tx_depth);
918 		geni_se_config_packing(&gi2c->se, BITS_PER_BYTE,
919 				       PACKING_BYTES_PW, true, true, true);
920 
921 		dev_dbg(dev, "i2c fifo/se-dma mode. fifo depth:%d\n", tx_depth);
922 	}
923 
924 	clk_disable_unprepare(gi2c->core_clk);
925 	ret = geni_se_resources_off(&gi2c->se);
926 	if (ret) {
927 		dev_err(dev, "Error turning off resources %d\n", ret);
928 		goto err_dma;
929 	}
930 
931 	ret = geni_icc_disable(&gi2c->se);
932 	if (ret)
933 		goto err_dma;
934 
935 	gi2c->suspended = 1;
936 	pm_runtime_set_suspended(gi2c->se.dev);
937 	pm_runtime_set_autosuspend_delay(gi2c->se.dev, I2C_AUTO_SUSPEND_DELAY);
938 	pm_runtime_use_autosuspend(gi2c->se.dev);
939 	pm_runtime_enable(gi2c->se.dev);
940 
941 	ret = i2c_add_adapter(&gi2c->adap);
942 	if (ret) {
943 		dev_err(dev, "Error adding i2c adapter %d\n", ret);
944 		pm_runtime_disable(gi2c->se.dev);
945 		goto err_dma;
946 	}
947 
948 	dev_dbg(dev, "Geni-I2C adaptor successfully added\n");
949 
950 	return 0;
951 
952 err_dma:
953 	release_gpi_dma(gi2c);
954 	return ret;
955 }
956 
957 static void geni_i2c_remove(struct platform_device *pdev)
958 {
959 	struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev);
960 
961 	i2c_del_adapter(&gi2c->adap);
962 	release_gpi_dma(gi2c);
963 	pm_runtime_disable(gi2c->se.dev);
964 }
965 
966 static void geni_i2c_shutdown(struct platform_device *pdev)
967 {
968 	struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev);
969 
970 	/* Make client i2c transfers start failing */
971 	i2c_mark_adapter_suspended(&gi2c->adap);
972 }
973 
974 static int __maybe_unused geni_i2c_runtime_suspend(struct device *dev)
975 {
976 	int ret;
977 	struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
978 
979 	disable_irq(gi2c->irq);
980 	ret = geni_se_resources_off(&gi2c->se);
981 	if (ret) {
982 		enable_irq(gi2c->irq);
983 		return ret;
984 
985 	} else {
986 		gi2c->suspended = 1;
987 	}
988 
989 	clk_disable_unprepare(gi2c->core_clk);
990 
991 	return geni_icc_disable(&gi2c->se);
992 }
993 
994 static int __maybe_unused geni_i2c_runtime_resume(struct device *dev)
995 {
996 	int ret;
997 	struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
998 
999 	ret = geni_icc_enable(&gi2c->se);
1000 	if (ret)
1001 		return ret;
1002 
1003 	ret = clk_prepare_enable(gi2c->core_clk);
1004 	if (ret)
1005 		goto out_icc_disable;
1006 
1007 	ret = geni_se_resources_on(&gi2c->se);
1008 	if (ret)
1009 		goto out_clk_disable;
1010 
1011 	enable_irq(gi2c->irq);
1012 	gi2c->suspended = 0;
1013 
1014 	return 0;
1015 
1016 out_clk_disable:
1017 	clk_disable_unprepare(gi2c->core_clk);
1018 out_icc_disable:
1019 	geni_icc_disable(&gi2c->se);
1020 
1021 	return ret;
1022 }
1023 
1024 static int __maybe_unused geni_i2c_suspend_noirq(struct device *dev)
1025 {
1026 	struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
1027 
1028 	i2c_mark_adapter_suspended(&gi2c->adap);
1029 
1030 	if (!gi2c->suspended) {
1031 		geni_i2c_runtime_suspend(dev);
1032 		pm_runtime_disable(dev);
1033 		pm_runtime_set_suspended(dev);
1034 		pm_runtime_enable(dev);
1035 	}
1036 	return 0;
1037 }
1038 
1039 static int __maybe_unused geni_i2c_resume_noirq(struct device *dev)
1040 {
1041 	struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
1042 
1043 	i2c_mark_adapter_resumed(&gi2c->adap);
1044 	return 0;
1045 }
1046 
1047 static const struct dev_pm_ops geni_i2c_pm_ops = {
1048 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(geni_i2c_suspend_noirq, geni_i2c_resume_noirq)
1049 	SET_RUNTIME_PM_OPS(geni_i2c_runtime_suspend, geni_i2c_runtime_resume,
1050 									NULL)
1051 };
1052 
1053 static const struct geni_i2c_desc i2c_master_hub = {
1054 	.has_core_clk = true,
1055 	.icc_ddr = NULL,
1056 	.no_dma_support = true,
1057 	.tx_fifo_depth = 16,
1058 };
1059 
1060 static const struct of_device_id geni_i2c_dt_match[] = {
1061 	{ .compatible = "qcom,geni-i2c" },
1062 	{ .compatible = "qcom,geni-i2c-master-hub", .data = &i2c_master_hub },
1063 	{}
1064 };
1065 MODULE_DEVICE_TABLE(of, geni_i2c_dt_match);
1066 
1067 static struct platform_driver geni_i2c_driver = {
1068 	.probe  = geni_i2c_probe,
1069 	.remove = geni_i2c_remove,
1070 	.shutdown = geni_i2c_shutdown,
1071 	.driver = {
1072 		.name = "geni_i2c",
1073 		.pm = &geni_i2c_pm_ops,
1074 		.of_match_table = geni_i2c_dt_match,
1075 		.acpi_match_table = ACPI_PTR(geni_i2c_acpi_match),
1076 	},
1077 };
1078 
1079 module_platform_driver(geni_i2c_driver);
1080 
1081 MODULE_DESCRIPTION("I2C Controller Driver for GENI based QUP cores");
1082 MODULE_LICENSE("GPL v2");
1083