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/qcom-geni-se.h>
18 #include <linux/spinlock.h>
19 
20 #define SE_I2C_TX_TRANS_LEN		0x26c
21 #define SE_I2C_RX_TRANS_LEN		0x270
22 #define SE_I2C_SCL_COUNTERS		0x278
23 
24 #define SE_I2C_ERR  (M_CMD_OVERRUN_EN | M_ILLEGAL_CMD_EN | M_CMD_FAILURE_EN |\
25 			M_GP_IRQ_1_EN | M_GP_IRQ_3_EN | M_GP_IRQ_4_EN)
26 #define SE_I2C_ABORT		BIT(1)
27 
28 /* M_CMD OP codes for I2C */
29 #define I2C_WRITE		0x1
30 #define I2C_READ		0x2
31 #define I2C_WRITE_READ		0x3
32 #define I2C_ADDR_ONLY		0x4
33 #define I2C_BUS_CLEAR		0x6
34 #define I2C_STOP_ON_BUS		0x7
35 /* M_CMD params for I2C */
36 #define PRE_CMD_DELAY		BIT(0)
37 #define TIMESTAMP_BEFORE	BIT(1)
38 #define STOP_STRETCH		BIT(2)
39 #define TIMESTAMP_AFTER		BIT(3)
40 #define POST_COMMAND_DELAY	BIT(4)
41 #define IGNORE_ADD_NACK		BIT(6)
42 #define READ_FINISHED_WITH_ACK	BIT(7)
43 #define BYPASS_ADDR_PHASE	BIT(8)
44 #define SLV_ADDR_MSK		GENMASK(15, 9)
45 #define SLV_ADDR_SHFT		9
46 /* I2C SCL COUNTER fields */
47 #define HIGH_COUNTER_MSK	GENMASK(29, 20)
48 #define HIGH_COUNTER_SHFT	20
49 #define LOW_COUNTER_MSK		GENMASK(19, 10)
50 #define LOW_COUNTER_SHFT	10
51 #define CYCLE_COUNTER_MSK	GENMASK(9, 0)
52 
53 #define I2C_PACK_TX		BIT(0)
54 #define I2C_PACK_RX		BIT(1)
55 
56 enum geni_i2c_err_code {
57 	GP_IRQ0,
58 	NACK,
59 	GP_IRQ2,
60 	BUS_PROTO,
61 	ARB_LOST,
62 	GP_IRQ5,
63 	GENI_OVERRUN,
64 	GENI_ILLEGAL_CMD,
65 	GENI_ABORT_DONE,
66 	GENI_TIMEOUT,
67 };
68 
69 #define DM_I2C_CB_ERR		((BIT(NACK) | BIT(BUS_PROTO) | BIT(ARB_LOST)) \
70 									<< 5)
71 
72 #define I2C_AUTO_SUSPEND_DELAY	250
73 #define KHZ(freq)		(1000 * freq)
74 #define PACKING_BYTES_PW	4
75 
76 #define ABORT_TIMEOUT		HZ
77 #define XFER_TIMEOUT		HZ
78 #define RST_TIMEOUT		HZ
79 
80 struct geni_i2c_dev {
81 	struct geni_se se;
82 	u32 tx_wm;
83 	int irq;
84 	int err;
85 	struct i2c_adapter adap;
86 	struct completion done;
87 	struct i2c_msg *cur;
88 	int cur_wr;
89 	int cur_rd;
90 	spinlock_t lock;
91 	u32 clk_freq_out;
92 	const struct geni_i2c_clk_fld *clk_fld;
93 	int suspended;
94 	void *dma_buf;
95 	size_t xfer_len;
96 	dma_addr_t dma_addr;
97 	struct dma_chan *tx_c;
98 	struct dma_chan *rx_c;
99 	bool gpi_mode;
100 	bool abort_done;
101 };
102 
103 struct geni_i2c_err_log {
104 	int err;
105 	const char *msg;
106 };
107 
108 static const struct geni_i2c_err_log gi2c_log[] = {
109 	[GP_IRQ0] = {-EIO, "Unknown I2C err GP_IRQ0"},
110 	[NACK] = {-ENXIO, "NACK: slv unresponsive, check its power/reset-ln"},
111 	[GP_IRQ2] = {-EIO, "Unknown I2C err GP IRQ2"},
112 	[BUS_PROTO] = {-EPROTO, "Bus proto err, noisy/unexpected start/stop"},
113 	[ARB_LOST] = {-EAGAIN, "Bus arbitration lost, clock line undriveable"},
114 	[GP_IRQ5] = {-EIO, "Unknown I2C err GP IRQ5"},
115 	[GENI_OVERRUN] = {-EIO, "Cmd overrun, check GENI cmd-state machine"},
116 	[GENI_ILLEGAL_CMD] = {-EIO, "Illegal cmd, check GENI cmd-state machine"},
117 	[GENI_ABORT_DONE] = {-ETIMEDOUT, "Abort after timeout successful"},
118 	[GENI_TIMEOUT] = {-ETIMEDOUT, "I2C TXN timed out"},
119 };
120 
121 struct geni_i2c_clk_fld {
122 	u32	clk_freq_out;
123 	u8	clk_div;
124 	u8	t_high_cnt;
125 	u8	t_low_cnt;
126 	u8	t_cycle_cnt;
127 };
128 
129 /*
130  * Hardware uses the underlying formula to calculate time periods of
131  * SCL clock cycle. Firmware uses some additional cycles excluded from the
132  * below formula and it is confirmed that the time periods are within
133  * specification limits.
134  *
135  * time of high period of SCL: t_high = (t_high_cnt * clk_div) / source_clock
136  * time of low period of SCL: t_low = (t_low_cnt * clk_div) / source_clock
137  * time of full period of SCL: t_cycle = (t_cycle_cnt * clk_div) / source_clock
138  * clk_freq_out = t / t_cycle
139  * source_clock = 19.2 MHz
140  */
141 static const struct geni_i2c_clk_fld geni_i2c_clk_map[] = {
142 	{KHZ(100), 7, 10, 11, 26},
143 	{KHZ(400), 2,  5, 12, 24},
144 	{KHZ(1000), 1, 3,  9, 18},
145 };
146 
147 static int geni_i2c_clk_map_idx(struct geni_i2c_dev *gi2c)
148 {
149 	int i;
150 	const struct geni_i2c_clk_fld *itr = geni_i2c_clk_map;
151 
152 	for (i = 0; i < ARRAY_SIZE(geni_i2c_clk_map); i++, itr++) {
153 		if (itr->clk_freq_out == gi2c->clk_freq_out) {
154 			gi2c->clk_fld = itr;
155 			return 0;
156 		}
157 	}
158 	return -EINVAL;
159 }
160 
161 static void qcom_geni_i2c_conf(struct geni_i2c_dev *gi2c)
162 {
163 	const struct geni_i2c_clk_fld *itr = gi2c->clk_fld;
164 	u32 val;
165 
166 	writel_relaxed(0, gi2c->se.base + SE_GENI_CLK_SEL);
167 
168 	val = (itr->clk_div << CLK_DIV_SHFT) | SER_CLK_EN;
169 	writel_relaxed(val, gi2c->se.base + GENI_SER_M_CLK_CFG);
170 
171 	val = itr->t_high_cnt << HIGH_COUNTER_SHFT;
172 	val |= itr->t_low_cnt << LOW_COUNTER_SHFT;
173 	val |= itr->t_cycle_cnt;
174 	writel_relaxed(val, gi2c->se.base + SE_I2C_SCL_COUNTERS);
175 }
176 
177 static void geni_i2c_err_misc(struct geni_i2c_dev *gi2c)
178 {
179 	u32 m_cmd = readl_relaxed(gi2c->se.base + SE_GENI_M_CMD0);
180 	u32 m_stat = readl_relaxed(gi2c->se.base + SE_GENI_M_IRQ_STATUS);
181 	u32 geni_s = readl_relaxed(gi2c->se.base + SE_GENI_STATUS);
182 	u32 geni_ios = readl_relaxed(gi2c->se.base + SE_GENI_IOS);
183 	u32 dma = readl_relaxed(gi2c->se.base + SE_GENI_DMA_MODE_EN);
184 	u32 rx_st, tx_st;
185 
186 	if (dma) {
187 		rx_st = readl_relaxed(gi2c->se.base + SE_DMA_RX_IRQ_STAT);
188 		tx_st = readl_relaxed(gi2c->se.base + SE_DMA_TX_IRQ_STAT);
189 	} else {
190 		rx_st = readl_relaxed(gi2c->se.base + SE_GENI_RX_FIFO_STATUS);
191 		tx_st = readl_relaxed(gi2c->se.base + SE_GENI_TX_FIFO_STATUS);
192 	}
193 	dev_dbg(gi2c->se.dev, "DMA:%d tx_stat:0x%x, rx_stat:0x%x, irq-stat:0x%x\n",
194 		dma, tx_st, rx_st, m_stat);
195 	dev_dbg(gi2c->se.dev, "m_cmd:0x%x, geni_status:0x%x, geni_ios:0x%x\n",
196 		m_cmd, geni_s, geni_ios);
197 }
198 
199 static void geni_i2c_err(struct geni_i2c_dev *gi2c, int err)
200 {
201 	if (!gi2c->err)
202 		gi2c->err = gi2c_log[err].err;
203 	if (gi2c->cur)
204 		dev_dbg(gi2c->se.dev, "len:%d, slv-addr:0x%x, RD/WR:%d\n",
205 			gi2c->cur->len, gi2c->cur->addr, gi2c->cur->flags);
206 
207 	switch (err) {
208 	case GENI_ABORT_DONE:
209 		gi2c->abort_done = true;
210 		break;
211 	case NACK:
212 	case GENI_TIMEOUT:
213 		dev_dbg(gi2c->se.dev, "%s\n", gi2c_log[err].msg);
214 		break;
215 	default:
216 		dev_err(gi2c->se.dev, "%s\n", gi2c_log[err].msg);
217 		geni_i2c_err_misc(gi2c);
218 		break;
219 	}
220 }
221 
222 static irqreturn_t geni_i2c_irq(int irq, void *dev)
223 {
224 	struct geni_i2c_dev *gi2c = dev;
225 	void __iomem *base = gi2c->se.base;
226 	int j, p;
227 	u32 m_stat;
228 	u32 rx_st;
229 	u32 dm_tx_st;
230 	u32 dm_rx_st;
231 	u32 dma;
232 	u32 val;
233 	struct i2c_msg *cur;
234 
235 	spin_lock(&gi2c->lock);
236 	m_stat = readl_relaxed(base + SE_GENI_M_IRQ_STATUS);
237 	rx_st = readl_relaxed(base + SE_GENI_RX_FIFO_STATUS);
238 	dm_tx_st = readl_relaxed(base + SE_DMA_TX_IRQ_STAT);
239 	dm_rx_st = readl_relaxed(base + SE_DMA_RX_IRQ_STAT);
240 	dma = readl_relaxed(base + SE_GENI_DMA_MODE_EN);
241 	cur = gi2c->cur;
242 
243 	if (!cur ||
244 	    m_stat & (M_CMD_FAILURE_EN | M_CMD_ABORT_EN) ||
245 	    dm_rx_st & (DM_I2C_CB_ERR)) {
246 		if (m_stat & M_GP_IRQ_1_EN)
247 			geni_i2c_err(gi2c, NACK);
248 		if (m_stat & M_GP_IRQ_3_EN)
249 			geni_i2c_err(gi2c, BUS_PROTO);
250 		if (m_stat & M_GP_IRQ_4_EN)
251 			geni_i2c_err(gi2c, ARB_LOST);
252 		if (m_stat & M_CMD_OVERRUN_EN)
253 			geni_i2c_err(gi2c, GENI_OVERRUN);
254 		if (m_stat & M_ILLEGAL_CMD_EN)
255 			geni_i2c_err(gi2c, GENI_ILLEGAL_CMD);
256 		if (m_stat & M_CMD_ABORT_EN)
257 			geni_i2c_err(gi2c, GENI_ABORT_DONE);
258 		if (m_stat & M_GP_IRQ_0_EN)
259 			geni_i2c_err(gi2c, GP_IRQ0);
260 
261 		/* Disable the TX Watermark interrupt to stop TX */
262 		if (!dma)
263 			writel_relaxed(0, base + SE_GENI_TX_WATERMARK_REG);
264 	} else if (dma) {
265 		dev_dbg(gi2c->se.dev, "i2c dma tx:0x%x, dma rx:0x%x\n",
266 			dm_tx_st, dm_rx_st);
267 	} else if (cur->flags & I2C_M_RD &&
268 		   m_stat & (M_RX_FIFO_WATERMARK_EN | M_RX_FIFO_LAST_EN)) {
269 		u32 rxcnt = rx_st & RX_FIFO_WC_MSK;
270 
271 		for (j = 0; j < rxcnt; j++) {
272 			p = 0;
273 			val = readl_relaxed(base + SE_GENI_RX_FIFOn);
274 			while (gi2c->cur_rd < cur->len && p < sizeof(val)) {
275 				cur->buf[gi2c->cur_rd++] = val & 0xff;
276 				val >>= 8;
277 				p++;
278 			}
279 			if (gi2c->cur_rd == cur->len)
280 				break;
281 		}
282 	} else if (!(cur->flags & I2C_M_RD) &&
283 		   m_stat & M_TX_FIFO_WATERMARK_EN) {
284 		for (j = 0; j < gi2c->tx_wm; j++) {
285 			u32 temp;
286 
287 			val = 0;
288 			p = 0;
289 			while (gi2c->cur_wr < cur->len && p < sizeof(val)) {
290 				temp = cur->buf[gi2c->cur_wr++];
291 				val |= temp << (p * 8);
292 				p++;
293 			}
294 			writel_relaxed(val, base + SE_GENI_TX_FIFOn);
295 			/* TX Complete, Disable the TX Watermark interrupt */
296 			if (gi2c->cur_wr == cur->len) {
297 				writel_relaxed(0, base + SE_GENI_TX_WATERMARK_REG);
298 				break;
299 			}
300 		}
301 	}
302 
303 	if (m_stat)
304 		writel_relaxed(m_stat, base + SE_GENI_M_IRQ_CLEAR);
305 
306 	if (dma && dm_tx_st)
307 		writel_relaxed(dm_tx_st, base + SE_DMA_TX_IRQ_CLR);
308 	if (dma && dm_rx_st)
309 		writel_relaxed(dm_rx_st, base + SE_DMA_RX_IRQ_CLR);
310 
311 	/* if this is err with done-bit not set, handle that through timeout. */
312 	if (m_stat & M_CMD_DONE_EN || m_stat & M_CMD_ABORT_EN ||
313 	    dm_tx_st & TX_DMA_DONE || dm_tx_st & TX_RESET_DONE ||
314 	    dm_rx_st & RX_DMA_DONE || dm_rx_st & RX_RESET_DONE)
315 		complete(&gi2c->done);
316 
317 	spin_unlock(&gi2c->lock);
318 
319 	return IRQ_HANDLED;
320 }
321 
322 static void geni_i2c_abort_xfer(struct geni_i2c_dev *gi2c)
323 {
324 	unsigned long time_left = ABORT_TIMEOUT;
325 	unsigned long flags;
326 
327 	spin_lock_irqsave(&gi2c->lock, flags);
328 	geni_i2c_err(gi2c, GENI_TIMEOUT);
329 	gi2c->cur = NULL;
330 	gi2c->abort_done = false;
331 	geni_se_abort_m_cmd(&gi2c->se);
332 	spin_unlock_irqrestore(&gi2c->lock, flags);
333 
334 	do {
335 		time_left = wait_for_completion_timeout(&gi2c->done, time_left);
336 	} while (!gi2c->abort_done && time_left);
337 
338 	if (!time_left)
339 		dev_err(gi2c->se.dev, "Timeout abort_m_cmd\n");
340 }
341 
342 static void geni_i2c_rx_fsm_rst(struct geni_i2c_dev *gi2c)
343 {
344 	u32 val;
345 	unsigned long time_left = RST_TIMEOUT;
346 
347 	writel_relaxed(1, gi2c->se.base + SE_DMA_RX_FSM_RST);
348 	do {
349 		time_left = wait_for_completion_timeout(&gi2c->done, time_left);
350 		val = readl_relaxed(gi2c->se.base + SE_DMA_RX_IRQ_STAT);
351 	} while (!(val & RX_RESET_DONE) && time_left);
352 
353 	if (!(val & RX_RESET_DONE))
354 		dev_err(gi2c->se.dev, "Timeout resetting RX_FSM\n");
355 }
356 
357 static void geni_i2c_tx_fsm_rst(struct geni_i2c_dev *gi2c)
358 {
359 	u32 val;
360 	unsigned long time_left = RST_TIMEOUT;
361 
362 	writel_relaxed(1, gi2c->se.base + SE_DMA_TX_FSM_RST);
363 	do {
364 		time_left = wait_for_completion_timeout(&gi2c->done, time_left);
365 		val = readl_relaxed(gi2c->se.base + SE_DMA_TX_IRQ_STAT);
366 	} while (!(val & TX_RESET_DONE) && time_left);
367 
368 	if (!(val & TX_RESET_DONE))
369 		dev_err(gi2c->se.dev, "Timeout resetting TX_FSM\n");
370 }
371 
372 static void geni_i2c_rx_msg_cleanup(struct geni_i2c_dev *gi2c,
373 				     struct i2c_msg *cur)
374 {
375 	gi2c->cur_rd = 0;
376 	if (gi2c->dma_buf) {
377 		if (gi2c->err)
378 			geni_i2c_rx_fsm_rst(gi2c);
379 		geni_se_rx_dma_unprep(&gi2c->se, gi2c->dma_addr, gi2c->xfer_len);
380 		i2c_put_dma_safe_msg_buf(gi2c->dma_buf, cur, !gi2c->err);
381 	}
382 }
383 
384 static void geni_i2c_tx_msg_cleanup(struct geni_i2c_dev *gi2c,
385 				     struct i2c_msg *cur)
386 {
387 	gi2c->cur_wr = 0;
388 	if (gi2c->dma_buf) {
389 		if (gi2c->err)
390 			geni_i2c_tx_fsm_rst(gi2c);
391 		geni_se_tx_dma_unprep(&gi2c->se, gi2c->dma_addr, gi2c->xfer_len);
392 		i2c_put_dma_safe_msg_buf(gi2c->dma_buf, cur, !gi2c->err);
393 	}
394 }
395 
396 static int geni_i2c_rx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
397 				u32 m_param)
398 {
399 	dma_addr_t rx_dma = 0;
400 	unsigned long time_left;
401 	void *dma_buf;
402 	struct geni_se *se = &gi2c->se;
403 	size_t len = msg->len;
404 	struct i2c_msg *cur;
405 
406 	dma_buf = i2c_get_dma_safe_msg_buf(msg, 32);
407 	if (dma_buf)
408 		geni_se_select_mode(se, GENI_SE_DMA);
409 	else
410 		geni_se_select_mode(se, GENI_SE_FIFO);
411 
412 	writel_relaxed(len, se->base + SE_I2C_RX_TRANS_LEN);
413 	geni_se_setup_m_cmd(se, I2C_READ, m_param);
414 
415 	if (dma_buf && geni_se_rx_dma_prep(se, dma_buf, len, &rx_dma)) {
416 		geni_se_select_mode(se, GENI_SE_FIFO);
417 		i2c_put_dma_safe_msg_buf(dma_buf, msg, false);
418 		dma_buf = NULL;
419 	} else {
420 		gi2c->xfer_len = len;
421 		gi2c->dma_addr = rx_dma;
422 		gi2c->dma_buf = dma_buf;
423 	}
424 
425 	cur = gi2c->cur;
426 	time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT);
427 	if (!time_left)
428 		geni_i2c_abort_xfer(gi2c);
429 
430 	geni_i2c_rx_msg_cleanup(gi2c, cur);
431 
432 	return gi2c->err;
433 }
434 
435 static int geni_i2c_tx_one_msg(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
436 				u32 m_param)
437 {
438 	dma_addr_t tx_dma = 0;
439 	unsigned long time_left;
440 	void *dma_buf;
441 	struct geni_se *se = &gi2c->se;
442 	size_t len = msg->len;
443 	struct i2c_msg *cur;
444 
445 	dma_buf = i2c_get_dma_safe_msg_buf(msg, 32);
446 	if (dma_buf)
447 		geni_se_select_mode(se, GENI_SE_DMA);
448 	else
449 		geni_se_select_mode(se, GENI_SE_FIFO);
450 
451 	writel_relaxed(len, se->base + SE_I2C_TX_TRANS_LEN);
452 	geni_se_setup_m_cmd(se, I2C_WRITE, m_param);
453 
454 	if (dma_buf && geni_se_tx_dma_prep(se, dma_buf, len, &tx_dma)) {
455 		geni_se_select_mode(se, GENI_SE_FIFO);
456 		i2c_put_dma_safe_msg_buf(dma_buf, msg, false);
457 		dma_buf = NULL;
458 	} else {
459 		gi2c->xfer_len = len;
460 		gi2c->dma_addr = tx_dma;
461 		gi2c->dma_buf = dma_buf;
462 	}
463 
464 	if (!dma_buf) /* Get FIFO IRQ */
465 		writel_relaxed(1, se->base + SE_GENI_TX_WATERMARK_REG);
466 
467 	cur = gi2c->cur;
468 	time_left = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT);
469 	if (!time_left)
470 		geni_i2c_abort_xfer(gi2c);
471 
472 	geni_i2c_tx_msg_cleanup(gi2c, cur);
473 
474 	return gi2c->err;
475 }
476 
477 static void i2c_gpi_cb_result(void *cb, const struct dmaengine_result *result)
478 {
479 	struct geni_i2c_dev *gi2c = cb;
480 
481 	if (result->result != DMA_TRANS_NOERROR) {
482 		dev_err(gi2c->se.dev, "DMA txn failed:%d\n", result->result);
483 		gi2c->err = -EIO;
484 	} else if (result->residue) {
485 		dev_dbg(gi2c->se.dev, "DMA xfer has pending: %d\n", result->residue);
486 	}
487 
488 	complete(&gi2c->done);
489 }
490 
491 static void geni_i2c_gpi_unmap(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
492 			       void *tx_buf, dma_addr_t tx_addr,
493 			       void *rx_buf, dma_addr_t rx_addr)
494 {
495 	if (tx_buf) {
496 		dma_unmap_single(gi2c->se.dev->parent, tx_addr, msg->len, DMA_TO_DEVICE);
497 		i2c_put_dma_safe_msg_buf(tx_buf, msg, !gi2c->err);
498 	}
499 
500 	if (rx_buf) {
501 		dma_unmap_single(gi2c->se.dev->parent, rx_addr, msg->len, DMA_FROM_DEVICE);
502 		i2c_put_dma_safe_msg_buf(rx_buf, msg, !gi2c->err);
503 	}
504 }
505 
506 static int geni_i2c_gpi(struct geni_i2c_dev *gi2c, struct i2c_msg *msg,
507 			struct dma_slave_config *config, dma_addr_t *dma_addr_p,
508 			void **buf, unsigned int op, struct dma_chan *dma_chan)
509 {
510 	struct gpi_i2c_config *peripheral;
511 	unsigned int flags;
512 	void *dma_buf;
513 	dma_addr_t addr;
514 	enum dma_data_direction map_dirn;
515 	enum dma_transfer_direction dma_dirn;
516 	struct dma_async_tx_descriptor *desc;
517 	int ret;
518 
519 	peripheral = config->peripheral_config;
520 
521 	dma_buf = i2c_get_dma_safe_msg_buf(msg, 1);
522 	if (!dma_buf)
523 		return -ENOMEM;
524 
525 	if (op == I2C_WRITE)
526 		map_dirn = DMA_TO_DEVICE;
527 	else
528 		map_dirn = DMA_FROM_DEVICE;
529 
530 	addr = dma_map_single(gi2c->se.dev->parent, dma_buf, msg->len, map_dirn);
531 	if (dma_mapping_error(gi2c->se.dev->parent, addr)) {
532 		i2c_put_dma_safe_msg_buf(dma_buf, msg, false);
533 		return -ENOMEM;
534 	}
535 
536 	/* set the length as message for rx txn */
537 	peripheral->rx_len = msg->len;
538 	peripheral->op = op;
539 
540 	ret = dmaengine_slave_config(dma_chan, config);
541 	if (ret) {
542 		dev_err(gi2c->se.dev, "dma config error: %d for op:%d\n", ret, op);
543 		goto err_config;
544 	}
545 
546 	peripheral->set_config = 0;
547 	peripheral->multi_msg = true;
548 	flags = DMA_PREP_INTERRUPT | DMA_CTRL_ACK;
549 
550 	if (op == I2C_WRITE)
551 		dma_dirn = DMA_MEM_TO_DEV;
552 	else
553 		dma_dirn = DMA_DEV_TO_MEM;
554 
555 	desc = dmaengine_prep_slave_single(dma_chan, addr, msg->len, dma_dirn, flags);
556 	if (!desc) {
557 		dev_err(gi2c->se.dev, "prep_slave_sg failed\n");
558 		ret = -EIO;
559 		goto err_config;
560 	}
561 
562 	desc->callback_result = i2c_gpi_cb_result;
563 	desc->callback_param = gi2c;
564 
565 	dmaengine_submit(desc);
566 	*buf = dma_buf;
567 	*dma_addr_p = addr;
568 
569 	return 0;
570 
571 err_config:
572 	dma_unmap_single(gi2c->se.dev->parent, addr, msg->len, map_dirn);
573 	i2c_put_dma_safe_msg_buf(dma_buf, msg, false);
574 	return ret;
575 }
576 
577 static int geni_i2c_gpi_xfer(struct geni_i2c_dev *gi2c, struct i2c_msg msgs[], int num)
578 {
579 	struct dma_slave_config config = {};
580 	struct gpi_i2c_config peripheral = {};
581 	int i, ret = 0, timeout;
582 	dma_addr_t tx_addr, rx_addr;
583 	void *tx_buf = NULL, *rx_buf = NULL;
584 	const struct geni_i2c_clk_fld *itr = gi2c->clk_fld;
585 
586 	config.peripheral_config = &peripheral;
587 	config.peripheral_size = sizeof(peripheral);
588 
589 	peripheral.pack_enable = I2C_PACK_TX | I2C_PACK_RX;
590 	peripheral.cycle_count = itr->t_cycle_cnt;
591 	peripheral.high_count = itr->t_high_cnt;
592 	peripheral.low_count = itr->t_low_cnt;
593 	peripheral.clk_div = itr->clk_div;
594 	peripheral.set_config = 1;
595 	peripheral.multi_msg = false;
596 
597 	for (i = 0; i < num; i++) {
598 		gi2c->cur = &msgs[i];
599 		gi2c->err = 0;
600 		dev_dbg(gi2c->se.dev, "msg[%d].len:%d\n", i, gi2c->cur->len);
601 
602 		peripheral.stretch = 0;
603 		if (i < num - 1)
604 			peripheral.stretch = 1;
605 
606 		peripheral.addr = msgs[i].addr;
607 
608 		if (msgs[i].flags & I2C_M_RD) {
609 			ret =  geni_i2c_gpi(gi2c, &msgs[i], &config,
610 					    &rx_addr, &rx_buf, I2C_READ, gi2c->rx_c);
611 			if (ret)
612 				goto err;
613 		}
614 
615 		ret =  geni_i2c_gpi(gi2c, &msgs[i], &config,
616 				    &tx_addr, &tx_buf, I2C_WRITE, gi2c->tx_c);
617 		if (ret)
618 			goto err;
619 
620 		if (msgs[i].flags & I2C_M_RD)
621 			dma_async_issue_pending(gi2c->rx_c);
622 		dma_async_issue_pending(gi2c->tx_c);
623 
624 		timeout = wait_for_completion_timeout(&gi2c->done, XFER_TIMEOUT);
625 		if (!timeout) {
626 			dev_err(gi2c->se.dev, "I2C timeout gpi flags:%d addr:0x%x\n",
627 				gi2c->cur->flags, gi2c->cur->addr);
628 			gi2c->err = -ETIMEDOUT;
629 			goto err;
630 		}
631 
632 		if (gi2c->err) {
633 			ret = gi2c->err;
634 			goto err;
635 		}
636 
637 		geni_i2c_gpi_unmap(gi2c, &msgs[i], tx_buf, tx_addr, rx_buf, rx_addr);
638 	}
639 
640 	return num;
641 
642 err:
643 	dev_err(gi2c->se.dev, "GPI transfer failed: %d\n", ret);
644 	dmaengine_terminate_sync(gi2c->rx_c);
645 	dmaengine_terminate_sync(gi2c->tx_c);
646 	geni_i2c_gpi_unmap(gi2c, &msgs[i], tx_buf, tx_addr, rx_buf, rx_addr);
647 	return ret;
648 }
649 
650 static int geni_i2c_fifo_xfer(struct geni_i2c_dev *gi2c,
651 			      struct i2c_msg msgs[], int num)
652 {
653 	int i, ret = 0;
654 
655 	for (i = 0; i < num; i++) {
656 		u32 m_param = i < (num - 1) ? STOP_STRETCH : 0;
657 
658 		m_param |= ((msgs[i].addr << SLV_ADDR_SHFT) & SLV_ADDR_MSK);
659 
660 		gi2c->cur = &msgs[i];
661 		if (msgs[i].flags & I2C_M_RD)
662 			ret = geni_i2c_rx_one_msg(gi2c, &msgs[i], m_param);
663 		else
664 			ret = geni_i2c_tx_one_msg(gi2c, &msgs[i], m_param);
665 
666 		if (ret)
667 			return ret;
668 	}
669 
670 	return num;
671 }
672 
673 static int geni_i2c_xfer(struct i2c_adapter *adap,
674 			 struct i2c_msg msgs[],
675 			 int num)
676 {
677 	struct geni_i2c_dev *gi2c = i2c_get_adapdata(adap);
678 	int ret;
679 
680 	gi2c->err = 0;
681 	reinit_completion(&gi2c->done);
682 	ret = pm_runtime_get_sync(gi2c->se.dev);
683 	if (ret < 0) {
684 		dev_err(gi2c->se.dev, "error turning SE resources:%d\n", ret);
685 		pm_runtime_put_noidle(gi2c->se.dev);
686 		/* Set device in suspended since resume failed */
687 		pm_runtime_set_suspended(gi2c->se.dev);
688 		return ret;
689 	}
690 
691 	qcom_geni_i2c_conf(gi2c);
692 
693 	if (gi2c->gpi_mode)
694 		ret = geni_i2c_gpi_xfer(gi2c, msgs, num);
695 	else
696 		ret = geni_i2c_fifo_xfer(gi2c, msgs, num);
697 
698 	pm_runtime_mark_last_busy(gi2c->se.dev);
699 	pm_runtime_put_autosuspend(gi2c->se.dev);
700 	gi2c->cur = NULL;
701 	gi2c->err = 0;
702 	return ret;
703 }
704 
705 static u32 geni_i2c_func(struct i2c_adapter *adap)
706 {
707 	return I2C_FUNC_I2C | (I2C_FUNC_SMBUS_EMUL & ~I2C_FUNC_SMBUS_QUICK);
708 }
709 
710 static const struct i2c_algorithm geni_i2c_algo = {
711 	.master_xfer	= geni_i2c_xfer,
712 	.functionality	= geni_i2c_func,
713 };
714 
715 #ifdef CONFIG_ACPI
716 static const struct acpi_device_id geni_i2c_acpi_match[] = {
717 	{ "QCOM0220"},
718 	{ },
719 };
720 MODULE_DEVICE_TABLE(acpi, geni_i2c_acpi_match);
721 #endif
722 
723 static void release_gpi_dma(struct geni_i2c_dev *gi2c)
724 {
725 	if (gi2c->rx_c)
726 		dma_release_channel(gi2c->rx_c);
727 
728 	if (gi2c->tx_c)
729 		dma_release_channel(gi2c->tx_c);
730 }
731 
732 static int setup_gpi_dma(struct geni_i2c_dev *gi2c)
733 {
734 	int ret;
735 
736 	geni_se_select_mode(&gi2c->se, GENI_GPI_DMA);
737 	gi2c->tx_c = dma_request_chan(gi2c->se.dev, "tx");
738 	if (IS_ERR(gi2c->tx_c)) {
739 		ret = dev_err_probe(gi2c->se.dev, PTR_ERR(gi2c->tx_c),
740 				    "Failed to get tx DMA ch\n");
741 		goto err_tx;
742 	}
743 
744 	gi2c->rx_c = dma_request_chan(gi2c->se.dev, "rx");
745 	if (IS_ERR(gi2c->rx_c)) {
746 		ret = dev_err_probe(gi2c->se.dev, PTR_ERR(gi2c->rx_c),
747 				    "Failed to get rx DMA ch\n");
748 		goto err_rx;
749 	}
750 
751 	dev_dbg(gi2c->se.dev, "Grabbed GPI dma channels\n");
752 	return 0;
753 
754 err_rx:
755 	dma_release_channel(gi2c->tx_c);
756 err_tx:
757 	return ret;
758 }
759 
760 static int geni_i2c_probe(struct platform_device *pdev)
761 {
762 	struct geni_i2c_dev *gi2c;
763 	struct resource *res;
764 	u32 proto, tx_depth, fifo_disable;
765 	int ret;
766 	struct device *dev = &pdev->dev;
767 
768 	gi2c = devm_kzalloc(dev, sizeof(*gi2c), GFP_KERNEL);
769 	if (!gi2c)
770 		return -ENOMEM;
771 
772 	gi2c->se.dev = dev;
773 	gi2c->se.wrapper = dev_get_drvdata(dev->parent);
774 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
775 	gi2c->se.base = devm_ioremap_resource(dev, res);
776 	if (IS_ERR(gi2c->se.base))
777 		return PTR_ERR(gi2c->se.base);
778 
779 	gi2c->se.clk = devm_clk_get(dev, "se");
780 	if (IS_ERR(gi2c->se.clk) && !has_acpi_companion(dev))
781 		return PTR_ERR(gi2c->se.clk);
782 
783 	ret = device_property_read_u32(dev, "clock-frequency",
784 				       &gi2c->clk_freq_out);
785 	if (ret) {
786 		dev_info(dev, "Bus frequency not specified, default to 100kHz.\n");
787 		gi2c->clk_freq_out = KHZ(100);
788 	}
789 
790 	if (has_acpi_companion(dev))
791 		ACPI_COMPANION_SET(&gi2c->adap.dev, ACPI_COMPANION(dev));
792 
793 	gi2c->irq = platform_get_irq(pdev, 0);
794 	if (gi2c->irq < 0)
795 		return gi2c->irq;
796 
797 	ret = geni_i2c_clk_map_idx(gi2c);
798 	if (ret) {
799 		dev_err(dev, "Invalid clk frequency %d Hz: %d\n",
800 			gi2c->clk_freq_out, ret);
801 		return ret;
802 	}
803 
804 	gi2c->adap.algo = &geni_i2c_algo;
805 	init_completion(&gi2c->done);
806 	spin_lock_init(&gi2c->lock);
807 	platform_set_drvdata(pdev, gi2c);
808 	ret = devm_request_irq(dev, gi2c->irq, geni_i2c_irq, 0,
809 			       dev_name(dev), gi2c);
810 	if (ret) {
811 		dev_err(dev, "Request_irq failed:%d: err:%d\n",
812 			gi2c->irq, ret);
813 		return ret;
814 	}
815 	/* Disable the interrupt so that the system can enter low-power mode */
816 	disable_irq(gi2c->irq);
817 	i2c_set_adapdata(&gi2c->adap, gi2c);
818 	gi2c->adap.dev.parent = dev;
819 	gi2c->adap.dev.of_node = dev->of_node;
820 	strscpy(gi2c->adap.name, "Geni-I2C", sizeof(gi2c->adap.name));
821 
822 	ret = geni_icc_get(&gi2c->se, "qup-memory");
823 	if (ret)
824 		return ret;
825 	/*
826 	 * Set the bus quota for core and cpu to a reasonable value for
827 	 * register access.
828 	 * Set quota for DDR based on bus speed.
829 	 */
830 	gi2c->se.icc_paths[GENI_TO_CORE].avg_bw = GENI_DEFAULT_BW;
831 	gi2c->se.icc_paths[CPU_TO_GENI].avg_bw = GENI_DEFAULT_BW;
832 	gi2c->se.icc_paths[GENI_TO_DDR].avg_bw = Bps_to_icc(gi2c->clk_freq_out);
833 
834 	ret = geni_icc_set_bw(&gi2c->se);
835 	if (ret)
836 		return ret;
837 
838 	ret = geni_se_resources_on(&gi2c->se);
839 	if (ret) {
840 		dev_err(dev, "Error turning on resources %d\n", ret);
841 		return ret;
842 	}
843 	proto = geni_se_read_proto(&gi2c->se);
844 	if (proto != GENI_SE_I2C) {
845 		dev_err(dev, "Invalid proto %d\n", proto);
846 		geni_se_resources_off(&gi2c->se);
847 		return -ENXIO;
848 	}
849 
850 	fifo_disable = readl_relaxed(gi2c->se.base + GENI_IF_DISABLE_RO) & FIFO_IF_DISABLE;
851 	if (fifo_disable) {
852 		/* FIFO is disabled, so we can only use GPI DMA */
853 		gi2c->gpi_mode = true;
854 		ret = setup_gpi_dma(gi2c);
855 		if (ret)
856 			return dev_err_probe(dev, ret, "Failed to setup GPI DMA mode\n");
857 
858 		dev_dbg(dev, "Using GPI DMA mode for I2C\n");
859 	} else {
860 		gi2c->gpi_mode = false;
861 		tx_depth = geni_se_get_tx_fifo_depth(&gi2c->se);
862 		gi2c->tx_wm = tx_depth - 1;
863 		geni_se_init(&gi2c->se, gi2c->tx_wm, tx_depth);
864 		geni_se_config_packing(&gi2c->se, BITS_PER_BYTE,
865 				       PACKING_BYTES_PW, true, true, true);
866 
867 		dev_dbg(dev, "i2c fifo/se-dma mode. fifo depth:%d\n", tx_depth);
868 	}
869 
870 	ret = geni_se_resources_off(&gi2c->se);
871 	if (ret) {
872 		dev_err(dev, "Error turning off resources %d\n", ret);
873 		goto err_dma;
874 	}
875 
876 	ret = geni_icc_disable(&gi2c->se);
877 	if (ret)
878 		goto err_dma;
879 
880 	gi2c->suspended = 1;
881 	pm_runtime_set_suspended(gi2c->se.dev);
882 	pm_runtime_set_autosuspend_delay(gi2c->se.dev, I2C_AUTO_SUSPEND_DELAY);
883 	pm_runtime_use_autosuspend(gi2c->se.dev);
884 	pm_runtime_enable(gi2c->se.dev);
885 
886 	ret = i2c_add_adapter(&gi2c->adap);
887 	if (ret) {
888 		dev_err(dev, "Error adding i2c adapter %d\n", ret);
889 		pm_runtime_disable(gi2c->se.dev);
890 		goto err_dma;
891 	}
892 
893 	dev_dbg(dev, "Geni-I2C adaptor successfully added\n");
894 
895 	return 0;
896 
897 err_dma:
898 	release_gpi_dma(gi2c);
899 	return ret;
900 }
901 
902 static int geni_i2c_remove(struct platform_device *pdev)
903 {
904 	struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev);
905 
906 	i2c_del_adapter(&gi2c->adap);
907 	release_gpi_dma(gi2c);
908 	pm_runtime_disable(gi2c->se.dev);
909 	return 0;
910 }
911 
912 static void geni_i2c_shutdown(struct platform_device *pdev)
913 {
914 	struct geni_i2c_dev *gi2c = platform_get_drvdata(pdev);
915 
916 	/* Make client i2c transfers start failing */
917 	i2c_mark_adapter_suspended(&gi2c->adap);
918 }
919 
920 static int __maybe_unused geni_i2c_runtime_suspend(struct device *dev)
921 {
922 	int ret;
923 	struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
924 
925 	disable_irq(gi2c->irq);
926 	ret = geni_se_resources_off(&gi2c->se);
927 	if (ret) {
928 		enable_irq(gi2c->irq);
929 		return ret;
930 
931 	} else {
932 		gi2c->suspended = 1;
933 	}
934 
935 	return geni_icc_disable(&gi2c->se);
936 }
937 
938 static int __maybe_unused geni_i2c_runtime_resume(struct device *dev)
939 {
940 	int ret;
941 	struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
942 
943 	ret = geni_icc_enable(&gi2c->se);
944 	if (ret)
945 		return ret;
946 
947 	ret = geni_se_resources_on(&gi2c->se);
948 	if (ret)
949 		return ret;
950 
951 	enable_irq(gi2c->irq);
952 	gi2c->suspended = 0;
953 	return 0;
954 }
955 
956 static int __maybe_unused geni_i2c_suspend_noirq(struct device *dev)
957 {
958 	struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
959 
960 	i2c_mark_adapter_suspended(&gi2c->adap);
961 
962 	if (!gi2c->suspended) {
963 		geni_i2c_runtime_suspend(dev);
964 		pm_runtime_disable(dev);
965 		pm_runtime_set_suspended(dev);
966 		pm_runtime_enable(dev);
967 	}
968 	return 0;
969 }
970 
971 static int __maybe_unused geni_i2c_resume_noirq(struct device *dev)
972 {
973 	struct geni_i2c_dev *gi2c = dev_get_drvdata(dev);
974 
975 	i2c_mark_adapter_resumed(&gi2c->adap);
976 	return 0;
977 }
978 
979 static const struct dev_pm_ops geni_i2c_pm_ops = {
980 	SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(geni_i2c_suspend_noirq, geni_i2c_resume_noirq)
981 	SET_RUNTIME_PM_OPS(geni_i2c_runtime_suspend, geni_i2c_runtime_resume,
982 									NULL)
983 };
984 
985 static const struct of_device_id geni_i2c_dt_match[] = {
986 	{ .compatible = "qcom,geni-i2c" },
987 	{}
988 };
989 MODULE_DEVICE_TABLE(of, geni_i2c_dt_match);
990 
991 static struct platform_driver geni_i2c_driver = {
992 	.probe  = geni_i2c_probe,
993 	.remove = geni_i2c_remove,
994 	.shutdown = geni_i2c_shutdown,
995 	.driver = {
996 		.name = "geni_i2c",
997 		.pm = &geni_i2c_pm_ops,
998 		.of_match_table = geni_i2c_dt_match,
999 		.acpi_match_table = ACPI_PTR(geni_i2c_acpi_match),
1000 	},
1001 };
1002 
1003 module_platform_driver(geni_i2c_driver);
1004 
1005 MODULE_DESCRIPTION("I2C Controller Driver for GENI based QUP cores");
1006 MODULE_LICENSE("GPL v2");
1007