1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (c) 2016, Fuzhou Rockchip Electronics Co., Ltd
4  * Copyright (C) STMicroelectronics SA 2017
5  *
6  * Modified by Philippe Cornu <philippe.cornu@st.com>
7  * This generic Synopsys DesignWare MIPI DSI host driver is based on the
8  * Rockchip version from rockchip/dw-mipi-dsi.c with phy & bridge APIs.
9  */
10 
11 #include <linux/clk.h>
12 #include <linux/component.h>
13 #include <linux/debugfs.h>
14 #include <linux/iopoll.h>
15 #include <linux/module.h>
16 #include <linux/of_device.h>
17 #include <linux/pm_runtime.h>
18 #include <linux/reset.h>
19 
20 #include <video/mipi_display.h>
21 
22 #include <drm/bridge/dw_mipi_dsi.h>
23 #include <drm/drm_atomic_helper.h>
24 #include <drm/drm_bridge.h>
25 #include <drm/drm_crtc.h>
26 #include <drm/drm_mipi_dsi.h>
27 #include <drm/drm_modes.h>
28 #include <drm/drm_of.h>
29 #include <drm/drm_print.h>
30 
31 #define HWVER_131			0x31333100	/* IP version 1.31 */
32 
33 #define DSI_VERSION			0x00
34 #define VERSION				GENMASK(31, 8)
35 
36 #define DSI_PWR_UP			0x04
37 #define RESET				0
38 #define POWERUP				BIT(0)
39 
40 #define DSI_CLKMGR_CFG			0x08
41 #define TO_CLK_DIVISION(div)		(((div) & 0xff) << 8)
42 #define TX_ESC_CLK_DIVISION(div)	((div) & 0xff)
43 
44 #define DSI_DPI_VCID			0x0c
45 #define DPI_VCID(vcid)			((vcid) & 0x3)
46 
47 #define DSI_DPI_COLOR_CODING		0x10
48 #define LOOSELY18_EN			BIT(8)
49 #define DPI_COLOR_CODING_16BIT_1	0x0
50 #define DPI_COLOR_CODING_16BIT_2	0x1
51 #define DPI_COLOR_CODING_16BIT_3	0x2
52 #define DPI_COLOR_CODING_18BIT_1	0x3
53 #define DPI_COLOR_CODING_18BIT_2	0x4
54 #define DPI_COLOR_CODING_24BIT		0x5
55 
56 #define DSI_DPI_CFG_POL			0x14
57 #define COLORM_ACTIVE_LOW		BIT(4)
58 #define SHUTD_ACTIVE_LOW		BIT(3)
59 #define HSYNC_ACTIVE_LOW		BIT(2)
60 #define VSYNC_ACTIVE_LOW		BIT(1)
61 #define DATAEN_ACTIVE_LOW		BIT(0)
62 
63 #define DSI_DPI_LP_CMD_TIM		0x18
64 #define OUTVACT_LPCMD_TIME(p)		(((p) & 0xff) << 16)
65 #define INVACT_LPCMD_TIME(p)		((p) & 0xff)
66 
67 #define DSI_DBI_VCID			0x1c
68 #define DSI_DBI_CFG			0x20
69 #define DSI_DBI_PARTITIONING_EN		0x24
70 #define DSI_DBI_CMDSIZE			0x28
71 
72 #define DSI_PCKHDL_CFG			0x2c
73 #define CRC_RX_EN			BIT(4)
74 #define ECC_RX_EN			BIT(3)
75 #define BTA_EN				BIT(2)
76 #define EOTP_RX_EN			BIT(1)
77 #define EOTP_TX_EN			BIT(0)
78 
79 #define DSI_GEN_VCID			0x30
80 
81 #define DSI_MODE_CFG			0x34
82 #define ENABLE_VIDEO_MODE		0
83 #define ENABLE_CMD_MODE			BIT(0)
84 
85 #define DSI_VID_MODE_CFG		0x38
86 #define ENABLE_LOW_POWER		(0x3f << 8)
87 #define ENABLE_LOW_POWER_MASK		(0x3f << 8)
88 #define VID_MODE_TYPE_NON_BURST_SYNC_PULSES	0x0
89 #define VID_MODE_TYPE_NON_BURST_SYNC_EVENTS	0x1
90 #define VID_MODE_TYPE_BURST			0x2
91 #define VID_MODE_TYPE_MASK			0x3
92 #define ENABLE_LOW_POWER_CMD		BIT(15)
93 #define VID_MODE_VPG_ENABLE		BIT(16)
94 #define VID_MODE_VPG_MODE		BIT(20)
95 #define VID_MODE_VPG_HORIZONTAL		BIT(24)
96 
97 #define DSI_VID_PKT_SIZE		0x3c
98 #define VID_PKT_SIZE(p)			((p) & 0x3fff)
99 
100 #define DSI_VID_NUM_CHUNKS		0x40
101 #define VID_NUM_CHUNKS(c)		((c) & 0x1fff)
102 
103 #define DSI_VID_NULL_SIZE		0x44
104 #define VID_NULL_SIZE(b)		((b) & 0x1fff)
105 
106 #define DSI_VID_HSA_TIME		0x48
107 #define DSI_VID_HBP_TIME		0x4c
108 #define DSI_VID_HLINE_TIME		0x50
109 #define DSI_VID_VSA_LINES		0x54
110 #define DSI_VID_VBP_LINES		0x58
111 #define DSI_VID_VFP_LINES		0x5c
112 #define DSI_VID_VACTIVE_LINES		0x60
113 #define DSI_EDPI_CMD_SIZE		0x64
114 
115 #define DSI_CMD_MODE_CFG		0x68
116 #define MAX_RD_PKT_SIZE_LP		BIT(24)
117 #define DCS_LW_TX_LP			BIT(19)
118 #define DCS_SR_0P_TX_LP			BIT(18)
119 #define DCS_SW_1P_TX_LP			BIT(17)
120 #define DCS_SW_0P_TX_LP			BIT(16)
121 #define GEN_LW_TX_LP			BIT(14)
122 #define GEN_SR_2P_TX_LP			BIT(13)
123 #define GEN_SR_1P_TX_LP			BIT(12)
124 #define GEN_SR_0P_TX_LP			BIT(11)
125 #define GEN_SW_2P_TX_LP			BIT(10)
126 #define GEN_SW_1P_TX_LP			BIT(9)
127 #define GEN_SW_0P_TX_LP			BIT(8)
128 #define ACK_RQST_EN			BIT(1)
129 #define TEAR_FX_EN			BIT(0)
130 
131 #define CMD_MODE_ALL_LP			(MAX_RD_PKT_SIZE_LP | \
132 					 DCS_LW_TX_LP | \
133 					 DCS_SR_0P_TX_LP | \
134 					 DCS_SW_1P_TX_LP | \
135 					 DCS_SW_0P_TX_LP | \
136 					 GEN_LW_TX_LP | \
137 					 GEN_SR_2P_TX_LP | \
138 					 GEN_SR_1P_TX_LP | \
139 					 GEN_SR_0P_TX_LP | \
140 					 GEN_SW_2P_TX_LP | \
141 					 GEN_SW_1P_TX_LP | \
142 					 GEN_SW_0P_TX_LP)
143 
144 #define DSI_GEN_HDR			0x6c
145 #define DSI_GEN_PLD_DATA		0x70
146 
147 #define DSI_CMD_PKT_STATUS		0x74
148 #define GEN_RD_CMD_BUSY			BIT(6)
149 #define GEN_PLD_R_FULL			BIT(5)
150 #define GEN_PLD_R_EMPTY			BIT(4)
151 #define GEN_PLD_W_FULL			BIT(3)
152 #define GEN_PLD_W_EMPTY			BIT(2)
153 #define GEN_CMD_FULL			BIT(1)
154 #define GEN_CMD_EMPTY			BIT(0)
155 
156 #define DSI_TO_CNT_CFG			0x78
157 #define HSTX_TO_CNT(p)			(((p) & 0xffff) << 16)
158 #define LPRX_TO_CNT(p)			((p) & 0xffff)
159 
160 #define DSI_HS_RD_TO_CNT		0x7c
161 #define DSI_LP_RD_TO_CNT		0x80
162 #define DSI_HS_WR_TO_CNT		0x84
163 #define DSI_LP_WR_TO_CNT		0x88
164 #define DSI_BTA_TO_CNT			0x8c
165 
166 #define DSI_LPCLK_CTRL			0x94
167 #define AUTO_CLKLANE_CTRL		BIT(1)
168 #define PHY_TXREQUESTCLKHS		BIT(0)
169 
170 #define DSI_PHY_TMR_LPCLK_CFG		0x98
171 #define PHY_CLKHS2LP_TIME(lbcc)		(((lbcc) & 0x3ff) << 16)
172 #define PHY_CLKLP2HS_TIME(lbcc)		((lbcc) & 0x3ff)
173 
174 #define DSI_PHY_TMR_CFG			0x9c
175 #define PHY_HS2LP_TIME(lbcc)		(((lbcc) & 0xff) << 24)
176 #define PHY_LP2HS_TIME(lbcc)		(((lbcc) & 0xff) << 16)
177 #define MAX_RD_TIME(lbcc)		((lbcc) & 0x7fff)
178 #define PHY_HS2LP_TIME_V131(lbcc)	(((lbcc) & 0x3ff) << 16)
179 #define PHY_LP2HS_TIME_V131(lbcc)	((lbcc) & 0x3ff)
180 
181 #define DSI_PHY_RSTZ			0xa0
182 #define PHY_DISFORCEPLL			0
183 #define PHY_ENFORCEPLL			BIT(3)
184 #define PHY_DISABLECLK			0
185 #define PHY_ENABLECLK			BIT(2)
186 #define PHY_RSTZ			0
187 #define PHY_UNRSTZ			BIT(1)
188 #define PHY_SHUTDOWNZ			0
189 #define PHY_UNSHUTDOWNZ			BIT(0)
190 
191 #define DSI_PHY_IF_CFG			0xa4
192 #define PHY_STOP_WAIT_TIME(cycle)	(((cycle) & 0xff) << 8)
193 #define N_LANES(n)			(((n) - 1) & 0x3)
194 
195 #define DSI_PHY_ULPS_CTRL		0xa8
196 #define DSI_PHY_TX_TRIGGERS		0xac
197 
198 #define DSI_PHY_STATUS			0xb0
199 #define PHY_STOP_STATE_CLK_LANE		BIT(2)
200 #define PHY_LOCK			BIT(0)
201 
202 #define DSI_PHY_TST_CTRL0		0xb4
203 #define PHY_TESTCLK			BIT(1)
204 #define PHY_UNTESTCLK			0
205 #define PHY_TESTCLR			BIT(0)
206 #define PHY_UNTESTCLR			0
207 
208 #define DSI_PHY_TST_CTRL1		0xb8
209 #define PHY_TESTEN			BIT(16)
210 #define PHY_UNTESTEN			0
211 #define PHY_TESTDOUT(n)			(((n) & 0xff) << 8)
212 #define PHY_TESTDIN(n)			((n) & 0xff)
213 
214 #define DSI_INT_ST0			0xbc
215 #define DSI_INT_ST1			0xc0
216 #define DSI_INT_MSK0			0xc4
217 #define DSI_INT_MSK1			0xc8
218 
219 #define DSI_PHY_TMR_RD_CFG		0xf4
220 #define MAX_RD_TIME_V131(lbcc)		((lbcc) & 0x7fff)
221 
222 #define PHY_STATUS_TIMEOUT_US		10000
223 #define CMD_PKT_STATUS_TIMEOUT_US	20000
224 
225 #ifdef CONFIG_DEBUG_FS
226 #define VPG_DEFS(name, dsi) \
227 	((void __force *)&((*dsi).vpg_defs.name))
228 
229 #define REGISTER(name, mask, dsi) \
230 	{ #name, VPG_DEFS(name, dsi), mask, dsi }
231 
232 struct debugfs_entries {
233 	const char				*name;
234 	bool					*reg;
235 	u32					mask;
236 	struct dw_mipi_dsi			*dsi;
237 };
238 #endif /* CONFIG_DEBUG_FS */
239 
240 struct dw_mipi_dsi {
241 	struct drm_bridge bridge;
242 	struct mipi_dsi_host dsi_host;
243 	struct drm_bridge *panel_bridge;
244 	struct device *dev;
245 	void __iomem *base;
246 
247 	struct clk *pclk;
248 
249 	unsigned int lane_mbps; /* per lane */
250 	u32 channel;
251 	u32 lanes;
252 	u32 format;
253 	unsigned long mode_flags;
254 
255 #ifdef CONFIG_DEBUG_FS
256 	struct dentry *debugfs;
257 	struct debugfs_entries *debugfs_vpg;
258 	struct {
259 		bool vpg;
260 		bool vpg_horizontal;
261 		bool vpg_ber_pattern;
262 	} vpg_defs;
263 #endif /* CONFIG_DEBUG_FS */
264 
265 	struct dw_mipi_dsi *master; /* dual-dsi master ptr */
266 	struct dw_mipi_dsi *slave; /* dual-dsi slave ptr */
267 
268 	const struct dw_mipi_dsi_plat_data *plat_data;
269 };
270 
271 /*
272  * Check if either a link to a master or slave is present
273  */
274 static inline bool dw_mipi_is_dual_mode(struct dw_mipi_dsi *dsi)
275 {
276 	return dsi->slave || dsi->master;
277 }
278 
279 /*
280  * The controller should generate 2 frames before
281  * preparing the peripheral.
282  */
283 static void dw_mipi_dsi_wait_for_two_frames(const struct drm_display_mode *mode)
284 {
285 	int refresh, two_frames;
286 
287 	refresh = drm_mode_vrefresh(mode);
288 	two_frames = DIV_ROUND_UP(MSEC_PER_SEC, refresh) * 2;
289 	msleep(two_frames);
290 }
291 
292 static inline struct dw_mipi_dsi *host_to_dsi(struct mipi_dsi_host *host)
293 {
294 	return container_of(host, struct dw_mipi_dsi, dsi_host);
295 }
296 
297 static inline struct dw_mipi_dsi *bridge_to_dsi(struct drm_bridge *bridge)
298 {
299 	return container_of(bridge, struct dw_mipi_dsi, bridge);
300 }
301 
302 static inline void dsi_write(struct dw_mipi_dsi *dsi, u32 reg, u32 val)
303 {
304 	writel(val, dsi->base + reg);
305 }
306 
307 static inline u32 dsi_read(struct dw_mipi_dsi *dsi, u32 reg)
308 {
309 	return readl(dsi->base + reg);
310 }
311 
312 static int dw_mipi_dsi_host_attach(struct mipi_dsi_host *host,
313 				   struct mipi_dsi_device *device)
314 {
315 	struct dw_mipi_dsi *dsi = host_to_dsi(host);
316 	const struct dw_mipi_dsi_plat_data *pdata = dsi->plat_data;
317 	struct drm_bridge *bridge;
318 	int ret;
319 
320 	if (device->lanes > dsi->plat_data->max_data_lanes) {
321 		dev_err(dsi->dev, "the number of data lanes(%u) is too many\n",
322 			device->lanes);
323 		return -EINVAL;
324 	}
325 
326 	dsi->lanes = device->lanes;
327 	dsi->channel = device->channel;
328 	dsi->format = device->format;
329 	dsi->mode_flags = device->mode_flags;
330 
331 	bridge = devm_drm_of_get_bridge(dsi->dev, dsi->dev->of_node, 1, 0);
332 	if (IS_ERR(bridge))
333 		return PTR_ERR(bridge);
334 
335 	dsi->panel_bridge = bridge;
336 
337 	drm_bridge_add(&dsi->bridge);
338 
339 	if (pdata->host_ops && pdata->host_ops->attach) {
340 		ret = pdata->host_ops->attach(pdata->priv_data, device);
341 		if (ret < 0)
342 			return ret;
343 	}
344 
345 	return 0;
346 }
347 
348 static int dw_mipi_dsi_host_detach(struct mipi_dsi_host *host,
349 				   struct mipi_dsi_device *device)
350 {
351 	struct dw_mipi_dsi *dsi = host_to_dsi(host);
352 	const struct dw_mipi_dsi_plat_data *pdata = dsi->plat_data;
353 	int ret;
354 
355 	if (pdata->host_ops && pdata->host_ops->detach) {
356 		ret = pdata->host_ops->detach(pdata->priv_data, device);
357 		if (ret < 0)
358 			return ret;
359 	}
360 
361 	drm_of_panel_bridge_remove(host->dev->of_node, 1, 0);
362 
363 	drm_bridge_remove(&dsi->bridge);
364 
365 	return 0;
366 }
367 
368 static void dw_mipi_message_config(struct dw_mipi_dsi *dsi,
369 				   const struct mipi_dsi_msg *msg)
370 {
371 	bool lpm = msg->flags & MIPI_DSI_MSG_USE_LPM;
372 	u32 val = 0;
373 
374 	/*
375 	 * TODO dw drv improvements
376 	 * largest packet sizes during hfp or during vsa/vpb/vfp
377 	 * should be computed according to byte lane, lane number and only
378 	 * if sending lp cmds in high speed is enable (PHY_TXREQUESTCLKHS)
379 	 */
380 	dsi_write(dsi, DSI_DPI_LP_CMD_TIM, OUTVACT_LPCMD_TIME(16)
381 		  | INVACT_LPCMD_TIME(4));
382 
383 	if (msg->flags & MIPI_DSI_MSG_REQ_ACK)
384 		val |= ACK_RQST_EN;
385 	if (lpm)
386 		val |= CMD_MODE_ALL_LP;
387 
388 	dsi_write(dsi, DSI_CMD_MODE_CFG, val);
389 
390 	val = dsi_read(dsi, DSI_VID_MODE_CFG);
391 	if (lpm)
392 		val |= ENABLE_LOW_POWER_CMD;
393 	else
394 		val &= ~ENABLE_LOW_POWER_CMD;
395 	dsi_write(dsi, DSI_VID_MODE_CFG, val);
396 }
397 
398 static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val)
399 {
400 	int ret;
401 	u32 val, mask;
402 
403 	ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
404 				 val, !(val & GEN_CMD_FULL), 1000,
405 				 CMD_PKT_STATUS_TIMEOUT_US);
406 	if (ret) {
407 		dev_err(dsi->dev, "failed to get available command FIFO\n");
408 		return ret;
409 	}
410 
411 	dsi_write(dsi, DSI_GEN_HDR, hdr_val);
412 
413 	mask = GEN_CMD_EMPTY | GEN_PLD_W_EMPTY;
414 	ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
415 				 val, (val & mask) == mask,
416 				 1000, CMD_PKT_STATUS_TIMEOUT_US);
417 	if (ret) {
418 		dev_err(dsi->dev, "failed to write command FIFO\n");
419 		return ret;
420 	}
421 
422 	return 0;
423 }
424 
425 static int dw_mipi_dsi_write(struct dw_mipi_dsi *dsi,
426 			     const struct mipi_dsi_packet *packet)
427 {
428 	const u8 *tx_buf = packet->payload;
429 	int len = packet->payload_length, pld_data_bytes = sizeof(u32), ret;
430 	__le32 word;
431 	u32 val;
432 
433 	while (len) {
434 		if (len < pld_data_bytes) {
435 			word = 0;
436 			memcpy(&word, tx_buf, len);
437 			dsi_write(dsi, DSI_GEN_PLD_DATA, le32_to_cpu(word));
438 			len = 0;
439 		} else {
440 			memcpy(&word, tx_buf, pld_data_bytes);
441 			dsi_write(dsi, DSI_GEN_PLD_DATA, le32_to_cpu(word));
442 			tx_buf += pld_data_bytes;
443 			len -= pld_data_bytes;
444 		}
445 
446 		ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
447 					 val, !(val & GEN_PLD_W_FULL), 1000,
448 					 CMD_PKT_STATUS_TIMEOUT_US);
449 		if (ret) {
450 			dev_err(dsi->dev,
451 				"failed to get available write payload FIFO\n");
452 			return ret;
453 		}
454 	}
455 
456 	word = 0;
457 	memcpy(&word, packet->header, sizeof(packet->header));
458 	return dw_mipi_dsi_gen_pkt_hdr_write(dsi, le32_to_cpu(word));
459 }
460 
461 static int dw_mipi_dsi_read(struct dw_mipi_dsi *dsi,
462 			    const struct mipi_dsi_msg *msg)
463 {
464 	int i, j, ret, len = msg->rx_len;
465 	u8 *buf = msg->rx_buf;
466 	u32 val;
467 
468 	/* Wait end of the read operation */
469 	ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
470 				 val, !(val & GEN_RD_CMD_BUSY),
471 				 1000, CMD_PKT_STATUS_TIMEOUT_US);
472 	if (ret) {
473 		dev_err(dsi->dev, "Timeout during read operation\n");
474 		return ret;
475 	}
476 
477 	for (i = 0; i < len; i += 4) {
478 		/* Read fifo must not be empty before all bytes are read */
479 		ret = readl_poll_timeout(dsi->base + DSI_CMD_PKT_STATUS,
480 					 val, !(val & GEN_PLD_R_EMPTY),
481 					 1000, CMD_PKT_STATUS_TIMEOUT_US);
482 		if (ret) {
483 			dev_err(dsi->dev, "Read payload FIFO is empty\n");
484 			return ret;
485 		}
486 
487 		val = dsi_read(dsi, DSI_GEN_PLD_DATA);
488 		for (j = 0; j < 4 && j + i < len; j++)
489 			buf[i + j] = val >> (8 * j);
490 	}
491 
492 	return ret;
493 }
494 
495 static ssize_t dw_mipi_dsi_host_transfer(struct mipi_dsi_host *host,
496 					 const struct mipi_dsi_msg *msg)
497 {
498 	struct dw_mipi_dsi *dsi = host_to_dsi(host);
499 	struct mipi_dsi_packet packet;
500 	int ret, nb_bytes;
501 
502 	ret = mipi_dsi_create_packet(&packet, msg);
503 	if (ret) {
504 		dev_err(dsi->dev, "failed to create packet: %d\n", ret);
505 		return ret;
506 	}
507 
508 	dw_mipi_message_config(dsi, msg);
509 	if (dsi->slave)
510 		dw_mipi_message_config(dsi->slave, msg);
511 
512 	ret = dw_mipi_dsi_write(dsi, &packet);
513 	if (ret)
514 		return ret;
515 	if (dsi->slave) {
516 		ret = dw_mipi_dsi_write(dsi->slave, &packet);
517 		if (ret)
518 			return ret;
519 	}
520 
521 	if (msg->rx_buf && msg->rx_len) {
522 		ret = dw_mipi_dsi_read(dsi, msg);
523 		if (ret)
524 			return ret;
525 		nb_bytes = msg->rx_len;
526 	} else {
527 		nb_bytes = packet.size;
528 	}
529 
530 	return nb_bytes;
531 }
532 
533 static const struct mipi_dsi_host_ops dw_mipi_dsi_host_ops = {
534 	.attach = dw_mipi_dsi_host_attach,
535 	.detach = dw_mipi_dsi_host_detach,
536 	.transfer = dw_mipi_dsi_host_transfer,
537 };
538 
539 static void dw_mipi_dsi_video_mode_config(struct dw_mipi_dsi *dsi)
540 {
541 	u32 val;
542 
543 	/*
544 	 * TODO dw drv improvements
545 	 * enabling low power is panel-dependent, we should use the
546 	 * panel configuration here...
547 	 */
548 	val = ENABLE_LOW_POWER;
549 
550 	if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_BURST)
551 		val |= VID_MODE_TYPE_BURST;
552 	else if (dsi->mode_flags & MIPI_DSI_MODE_VIDEO_SYNC_PULSE)
553 		val |= VID_MODE_TYPE_NON_BURST_SYNC_PULSES;
554 	else
555 		val |= VID_MODE_TYPE_NON_BURST_SYNC_EVENTS;
556 
557 #ifdef CONFIG_DEBUG_FS
558 	if (dsi->vpg_defs.vpg) {
559 		val |= VID_MODE_VPG_ENABLE;
560 		val |= dsi->vpg_defs.vpg_horizontal ?
561 		       VID_MODE_VPG_HORIZONTAL : 0;
562 		val |= dsi->vpg_defs.vpg_ber_pattern ? VID_MODE_VPG_MODE : 0;
563 	}
564 #endif /* CONFIG_DEBUG_FS */
565 
566 	dsi_write(dsi, DSI_VID_MODE_CFG, val);
567 }
568 
569 static void dw_mipi_dsi_set_mode(struct dw_mipi_dsi *dsi,
570 				 unsigned long mode_flags)
571 {
572 	u32 val;
573 
574 	dsi_write(dsi, DSI_PWR_UP, RESET);
575 
576 	if (mode_flags & MIPI_DSI_MODE_VIDEO) {
577 		dsi_write(dsi, DSI_MODE_CFG, ENABLE_VIDEO_MODE);
578 		dw_mipi_dsi_video_mode_config(dsi);
579 	} else {
580 		dsi_write(dsi, DSI_MODE_CFG, ENABLE_CMD_MODE);
581 	}
582 
583 	val = PHY_TXREQUESTCLKHS;
584 	if (dsi->mode_flags & MIPI_DSI_CLOCK_NON_CONTINUOUS)
585 		val |= AUTO_CLKLANE_CTRL;
586 	dsi_write(dsi, DSI_LPCLK_CTRL, val);
587 
588 	dsi_write(dsi, DSI_PWR_UP, POWERUP);
589 }
590 
591 static void dw_mipi_dsi_disable(struct dw_mipi_dsi *dsi)
592 {
593 	dsi_write(dsi, DSI_PWR_UP, RESET);
594 	dsi_write(dsi, DSI_PHY_RSTZ, PHY_RSTZ);
595 }
596 
597 static void dw_mipi_dsi_init(struct dw_mipi_dsi *dsi)
598 {
599 	const struct dw_mipi_dsi_phy_ops *phy_ops = dsi->plat_data->phy_ops;
600 	unsigned int esc_rate; /* in MHz */
601 	u32 esc_clk_division;
602 	int ret;
603 
604 	/*
605 	 * The maximum permitted escape clock is 20MHz and it is derived from
606 	 * lanebyteclk, which is running at "lane_mbps / 8".
607 	 */
608 	if (phy_ops->get_esc_clk_rate) {
609 		ret = phy_ops->get_esc_clk_rate(dsi->plat_data->priv_data,
610 						&esc_rate);
611 		if (ret)
612 			DRM_DEBUG_DRIVER("Phy get_esc_clk_rate() failed\n");
613 	} else
614 		esc_rate = 20; /* Default to 20MHz */
615 
616 	/*
617 	 * We want :
618 	 *     (lane_mbps >> 3) / esc_clk_division < X
619 	 * which is:
620 	 *     (lane_mbps >> 3) / X > esc_clk_division
621 	 */
622 	esc_clk_division = (dsi->lane_mbps >> 3) / esc_rate + 1;
623 
624 	dsi_write(dsi, DSI_PWR_UP, RESET);
625 
626 	/*
627 	 * TODO dw drv improvements
628 	 * timeout clock division should be computed with the
629 	 * high speed transmission counter timeout and byte lane...
630 	 */
631 	dsi_write(dsi, DSI_CLKMGR_CFG, TO_CLK_DIVISION(10) |
632 		  TX_ESC_CLK_DIVISION(esc_clk_division));
633 }
634 
635 static void dw_mipi_dsi_dpi_config(struct dw_mipi_dsi *dsi,
636 				   const struct drm_display_mode *mode)
637 {
638 	u32 val = 0, color = 0;
639 
640 	switch (dsi->format) {
641 	case MIPI_DSI_FMT_RGB888:
642 		color = DPI_COLOR_CODING_24BIT;
643 		break;
644 	case MIPI_DSI_FMT_RGB666:
645 		color = DPI_COLOR_CODING_18BIT_2 | LOOSELY18_EN;
646 		break;
647 	case MIPI_DSI_FMT_RGB666_PACKED:
648 		color = DPI_COLOR_CODING_18BIT_1;
649 		break;
650 	case MIPI_DSI_FMT_RGB565:
651 		color = DPI_COLOR_CODING_16BIT_1;
652 		break;
653 	}
654 
655 	if (mode->flags & DRM_MODE_FLAG_NVSYNC)
656 		val |= VSYNC_ACTIVE_LOW;
657 	if (mode->flags & DRM_MODE_FLAG_NHSYNC)
658 		val |= HSYNC_ACTIVE_LOW;
659 
660 	dsi_write(dsi, DSI_DPI_VCID, DPI_VCID(dsi->channel));
661 	dsi_write(dsi, DSI_DPI_COLOR_CODING, color);
662 	dsi_write(dsi, DSI_DPI_CFG_POL, val);
663 }
664 
665 static void dw_mipi_dsi_packet_handler_config(struct dw_mipi_dsi *dsi)
666 {
667 	dsi_write(dsi, DSI_PCKHDL_CFG, CRC_RX_EN | ECC_RX_EN | BTA_EN);
668 }
669 
670 static void dw_mipi_dsi_video_packet_config(struct dw_mipi_dsi *dsi,
671 					    const struct drm_display_mode *mode)
672 {
673 	/*
674 	 * TODO dw drv improvements
675 	 * only burst mode is supported here. For non-burst video modes,
676 	 * we should compute DSI_VID_PKT_SIZE, DSI_VCCR.NUMC &
677 	 * DSI_VNPCR.NPSIZE... especially because this driver supports
678 	 * non-burst video modes, see dw_mipi_dsi_video_mode_config()...
679 	 */
680 
681 	dsi_write(dsi, DSI_VID_PKT_SIZE,
682 		       dw_mipi_is_dual_mode(dsi) ?
683 				VID_PKT_SIZE(mode->hdisplay / 2) :
684 				VID_PKT_SIZE(mode->hdisplay));
685 }
686 
687 static void dw_mipi_dsi_command_mode_config(struct dw_mipi_dsi *dsi)
688 {
689 	/*
690 	 * TODO dw drv improvements
691 	 * compute high speed transmission counter timeout according
692 	 * to the timeout clock division (TO_CLK_DIVISION) and byte lane...
693 	 */
694 	dsi_write(dsi, DSI_TO_CNT_CFG, HSTX_TO_CNT(1000) | LPRX_TO_CNT(1000));
695 	/*
696 	 * TODO dw drv improvements
697 	 * the Bus-Turn-Around Timeout Counter should be computed
698 	 * according to byte lane...
699 	 */
700 	dsi_write(dsi, DSI_BTA_TO_CNT, 0xd00);
701 	dsi_write(dsi, DSI_MODE_CFG, ENABLE_CMD_MODE);
702 }
703 
704 /* Get lane byte clock cycles. */
705 static u32 dw_mipi_dsi_get_hcomponent_lbcc(struct dw_mipi_dsi *dsi,
706 					   const struct drm_display_mode *mode,
707 					   u32 hcomponent)
708 {
709 	u32 frac, lbcc;
710 
711 	lbcc = hcomponent * dsi->lane_mbps * MSEC_PER_SEC / 8;
712 
713 	frac = lbcc % mode->clock;
714 	lbcc = lbcc / mode->clock;
715 	if (frac)
716 		lbcc++;
717 
718 	return lbcc;
719 }
720 
721 static void dw_mipi_dsi_line_timer_config(struct dw_mipi_dsi *dsi,
722 					  const struct drm_display_mode *mode)
723 {
724 	u32 htotal, hsa, hbp, lbcc;
725 
726 	htotal = mode->htotal;
727 	hsa = mode->hsync_end - mode->hsync_start;
728 	hbp = mode->htotal - mode->hsync_end;
729 
730 	/*
731 	 * TODO dw drv improvements
732 	 * computations below may be improved...
733 	 */
734 	lbcc = dw_mipi_dsi_get_hcomponent_lbcc(dsi, mode, htotal);
735 	dsi_write(dsi, DSI_VID_HLINE_TIME, lbcc);
736 
737 	lbcc = dw_mipi_dsi_get_hcomponent_lbcc(dsi, mode, hsa);
738 	dsi_write(dsi, DSI_VID_HSA_TIME, lbcc);
739 
740 	lbcc = dw_mipi_dsi_get_hcomponent_lbcc(dsi, mode, hbp);
741 	dsi_write(dsi, DSI_VID_HBP_TIME, lbcc);
742 }
743 
744 static void dw_mipi_dsi_vertical_timing_config(struct dw_mipi_dsi *dsi,
745 					const struct drm_display_mode *mode)
746 {
747 	u32 vactive, vsa, vfp, vbp;
748 
749 	vactive = mode->vdisplay;
750 	vsa = mode->vsync_end - mode->vsync_start;
751 	vfp = mode->vsync_start - mode->vdisplay;
752 	vbp = mode->vtotal - mode->vsync_end;
753 
754 	dsi_write(dsi, DSI_VID_VACTIVE_LINES, vactive);
755 	dsi_write(dsi, DSI_VID_VSA_LINES, vsa);
756 	dsi_write(dsi, DSI_VID_VFP_LINES, vfp);
757 	dsi_write(dsi, DSI_VID_VBP_LINES, vbp);
758 }
759 
760 static void dw_mipi_dsi_dphy_timing_config(struct dw_mipi_dsi *dsi)
761 {
762 	const struct dw_mipi_dsi_phy_ops *phy_ops = dsi->plat_data->phy_ops;
763 	struct dw_mipi_dsi_dphy_timing timing;
764 	u32 hw_version;
765 	int ret;
766 
767 	ret = phy_ops->get_timing(dsi->plat_data->priv_data,
768 				  dsi->lane_mbps, &timing);
769 	if (ret)
770 		DRM_DEV_ERROR(dsi->dev, "Retrieving phy timings failed\n");
771 
772 	/*
773 	 * TODO dw drv improvements
774 	 * data & clock lane timers should be computed according to panel
775 	 * blankings and to the automatic clock lane control mode...
776 	 * note: DSI_PHY_TMR_CFG.MAX_RD_TIME should be in line with
777 	 * DSI_CMD_MODE_CFG.MAX_RD_PKT_SIZE_LP (see CMD_MODE_ALL_LP)
778 	 */
779 
780 	hw_version = dsi_read(dsi, DSI_VERSION) & VERSION;
781 
782 	if (hw_version >= HWVER_131) {
783 		dsi_write(dsi, DSI_PHY_TMR_CFG,
784 			  PHY_HS2LP_TIME_V131(timing.data_hs2lp) |
785 			  PHY_LP2HS_TIME_V131(timing.data_lp2hs));
786 		dsi_write(dsi, DSI_PHY_TMR_RD_CFG, MAX_RD_TIME_V131(10000));
787 	} else {
788 		dsi_write(dsi, DSI_PHY_TMR_CFG,
789 			  PHY_HS2LP_TIME(timing.data_hs2lp) |
790 			  PHY_LP2HS_TIME(timing.data_lp2hs) |
791 			  MAX_RD_TIME(10000));
792 	}
793 
794 	dsi_write(dsi, DSI_PHY_TMR_LPCLK_CFG,
795 		  PHY_CLKHS2LP_TIME(timing.clk_hs2lp) |
796 		  PHY_CLKLP2HS_TIME(timing.clk_lp2hs));
797 }
798 
799 static void dw_mipi_dsi_dphy_interface_config(struct dw_mipi_dsi *dsi)
800 {
801 	/*
802 	 * TODO dw drv improvements
803 	 * stop wait time should be the maximum between host dsi
804 	 * and panel stop wait times
805 	 */
806 	dsi_write(dsi, DSI_PHY_IF_CFG, PHY_STOP_WAIT_TIME(0x20) |
807 		  N_LANES(dsi->lanes));
808 }
809 
810 static void dw_mipi_dsi_dphy_init(struct dw_mipi_dsi *dsi)
811 {
812 	/* Clear PHY state */
813 	dsi_write(dsi, DSI_PHY_RSTZ, PHY_DISFORCEPLL | PHY_DISABLECLK
814 		  | PHY_RSTZ | PHY_SHUTDOWNZ);
815 	dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_UNTESTCLR);
816 	dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_TESTCLR);
817 	dsi_write(dsi, DSI_PHY_TST_CTRL0, PHY_UNTESTCLR);
818 }
819 
820 static void dw_mipi_dsi_dphy_enable(struct dw_mipi_dsi *dsi)
821 {
822 	u32 val;
823 	int ret;
824 
825 	dsi_write(dsi, DSI_PHY_RSTZ, PHY_ENFORCEPLL | PHY_ENABLECLK |
826 		  PHY_UNRSTZ | PHY_UNSHUTDOWNZ);
827 
828 	ret = readl_poll_timeout(dsi->base + DSI_PHY_STATUS, val,
829 				 val & PHY_LOCK, 1000, PHY_STATUS_TIMEOUT_US);
830 	if (ret)
831 		DRM_DEBUG_DRIVER("failed to wait phy lock state\n");
832 
833 	ret = readl_poll_timeout(dsi->base + DSI_PHY_STATUS,
834 				 val, val & PHY_STOP_STATE_CLK_LANE, 1000,
835 				 PHY_STATUS_TIMEOUT_US);
836 	if (ret)
837 		DRM_DEBUG_DRIVER("failed to wait phy clk lane stop state\n");
838 }
839 
840 static void dw_mipi_dsi_clear_err(struct dw_mipi_dsi *dsi)
841 {
842 	dsi_read(dsi, DSI_INT_ST0);
843 	dsi_read(dsi, DSI_INT_ST1);
844 	dsi_write(dsi, DSI_INT_MSK0, 0);
845 	dsi_write(dsi, DSI_INT_MSK1, 0);
846 }
847 
848 static void dw_mipi_dsi_bridge_post_atomic_disable(struct drm_bridge *bridge,
849 						   struct drm_bridge_state *old_bridge_state)
850 {
851 	struct dw_mipi_dsi *dsi = bridge_to_dsi(bridge);
852 	const struct dw_mipi_dsi_phy_ops *phy_ops = dsi->plat_data->phy_ops;
853 
854 	/*
855 	 * Switch to command mode before panel-bridge post_disable &
856 	 * panel unprepare.
857 	 * Note: panel-bridge disable & panel disable has been called
858 	 * before by the drm framework.
859 	 */
860 	dw_mipi_dsi_set_mode(dsi, 0);
861 
862 	/*
863 	 * TODO Only way found to call panel-bridge post_disable &
864 	 * panel unprepare before the dsi "final" disable...
865 	 * This needs to be fixed in the drm_bridge framework and the API
866 	 * needs to be updated to manage our own call chains...
867 	 */
868 	if (dsi->panel_bridge->funcs->post_disable)
869 		dsi->panel_bridge->funcs->post_disable(dsi->panel_bridge);
870 
871 	if (phy_ops->power_off)
872 		phy_ops->power_off(dsi->plat_data->priv_data);
873 
874 	if (dsi->slave) {
875 		dw_mipi_dsi_disable(dsi->slave);
876 		clk_disable_unprepare(dsi->slave->pclk);
877 		pm_runtime_put(dsi->slave->dev);
878 	}
879 	dw_mipi_dsi_disable(dsi);
880 
881 	clk_disable_unprepare(dsi->pclk);
882 	pm_runtime_put(dsi->dev);
883 }
884 
885 static unsigned int dw_mipi_dsi_get_lanes(struct dw_mipi_dsi *dsi)
886 {
887 	/* this instance is the slave, so add the master's lanes */
888 	if (dsi->master)
889 		return dsi->master->lanes + dsi->lanes;
890 
891 	/* this instance is the master, so add the slave's lanes */
892 	if (dsi->slave)
893 		return dsi->lanes + dsi->slave->lanes;
894 
895 	/* single-dsi, so no other instance to consider */
896 	return dsi->lanes;
897 }
898 
899 static void dw_mipi_dsi_mode_set(struct dw_mipi_dsi *dsi,
900 				 const struct drm_display_mode *adjusted_mode)
901 {
902 	const struct dw_mipi_dsi_phy_ops *phy_ops = dsi->plat_data->phy_ops;
903 	void *priv_data = dsi->plat_data->priv_data;
904 	int ret;
905 	u32 lanes = dw_mipi_dsi_get_lanes(dsi);
906 
907 	clk_prepare_enable(dsi->pclk);
908 
909 	ret = phy_ops->get_lane_mbps(priv_data, adjusted_mode, dsi->mode_flags,
910 				     lanes, dsi->format, &dsi->lane_mbps);
911 	if (ret)
912 		DRM_DEBUG_DRIVER("Phy get_lane_mbps() failed\n");
913 
914 	pm_runtime_get_sync(dsi->dev);
915 	dw_mipi_dsi_init(dsi);
916 	dw_mipi_dsi_dpi_config(dsi, adjusted_mode);
917 	dw_mipi_dsi_packet_handler_config(dsi);
918 	dw_mipi_dsi_video_mode_config(dsi);
919 	dw_mipi_dsi_video_packet_config(dsi, adjusted_mode);
920 	dw_mipi_dsi_command_mode_config(dsi);
921 	dw_mipi_dsi_line_timer_config(dsi, adjusted_mode);
922 	dw_mipi_dsi_vertical_timing_config(dsi, adjusted_mode);
923 
924 	dw_mipi_dsi_dphy_init(dsi);
925 	dw_mipi_dsi_dphy_timing_config(dsi);
926 	dw_mipi_dsi_dphy_interface_config(dsi);
927 
928 	dw_mipi_dsi_clear_err(dsi);
929 
930 	ret = phy_ops->init(priv_data);
931 	if (ret)
932 		DRM_DEBUG_DRIVER("Phy init() failed\n");
933 
934 	dw_mipi_dsi_dphy_enable(dsi);
935 
936 	dw_mipi_dsi_wait_for_two_frames(adjusted_mode);
937 
938 	/* Switch to cmd mode for panel-bridge pre_enable & panel prepare */
939 	dw_mipi_dsi_set_mode(dsi, 0);
940 
941 	if (phy_ops->power_on)
942 		phy_ops->power_on(dsi->plat_data->priv_data);
943 }
944 
945 static void dw_mipi_dsi_bridge_mode_set(struct drm_bridge *bridge,
946 					const struct drm_display_mode *mode,
947 					const struct drm_display_mode *adjusted_mode)
948 {
949 	struct dw_mipi_dsi *dsi = bridge_to_dsi(bridge);
950 
951 	dw_mipi_dsi_mode_set(dsi, adjusted_mode);
952 	if (dsi->slave)
953 		dw_mipi_dsi_mode_set(dsi->slave, adjusted_mode);
954 }
955 
956 static void dw_mipi_dsi_bridge_atomic_enable(struct drm_bridge *bridge,
957 					     struct drm_bridge_state *old_bridge_state)
958 {
959 	struct dw_mipi_dsi *dsi = bridge_to_dsi(bridge);
960 
961 	/* Switch to video mode for panel-bridge enable & panel enable */
962 	dw_mipi_dsi_set_mode(dsi, MIPI_DSI_MODE_VIDEO);
963 	if (dsi->slave)
964 		dw_mipi_dsi_set_mode(dsi->slave, MIPI_DSI_MODE_VIDEO);
965 }
966 
967 static enum drm_mode_status
968 dw_mipi_dsi_bridge_mode_valid(struct drm_bridge *bridge,
969 			      const struct drm_display_info *info,
970 			      const struct drm_display_mode *mode)
971 {
972 	struct dw_mipi_dsi *dsi = bridge_to_dsi(bridge);
973 	const struct dw_mipi_dsi_plat_data *pdata = dsi->plat_data;
974 	enum drm_mode_status mode_status = MODE_OK;
975 
976 	if (pdata->mode_valid)
977 		mode_status = pdata->mode_valid(pdata->priv_data, mode,
978 						dsi->mode_flags,
979 						dw_mipi_dsi_get_lanes(dsi),
980 						dsi->format);
981 
982 	return mode_status;
983 }
984 
985 static int dw_mipi_dsi_bridge_attach(struct drm_bridge *bridge,
986 				     enum drm_bridge_attach_flags flags)
987 {
988 	struct dw_mipi_dsi *dsi = bridge_to_dsi(bridge);
989 
990 	if (!bridge->encoder) {
991 		DRM_ERROR("Parent encoder object not found\n");
992 		return -ENODEV;
993 	}
994 
995 	/* Set the encoder type as caller does not know it */
996 	bridge->encoder->encoder_type = DRM_MODE_ENCODER_DSI;
997 
998 	/* Attach the panel-bridge to the dsi bridge */
999 	return drm_bridge_attach(bridge->encoder, dsi->panel_bridge, bridge,
1000 				 flags);
1001 }
1002 
1003 static const struct drm_bridge_funcs dw_mipi_dsi_bridge_funcs = {
1004 	.atomic_duplicate_state	= drm_atomic_helper_bridge_duplicate_state,
1005 	.atomic_destroy_state	= drm_atomic_helper_bridge_destroy_state,
1006 	.atomic_reset		= drm_atomic_helper_bridge_reset,
1007 	.atomic_enable		= dw_mipi_dsi_bridge_atomic_enable,
1008 	.atomic_post_disable	= dw_mipi_dsi_bridge_post_atomic_disable,
1009 	.mode_set		= dw_mipi_dsi_bridge_mode_set,
1010 	.mode_valid		= dw_mipi_dsi_bridge_mode_valid,
1011 	.attach			= dw_mipi_dsi_bridge_attach,
1012 };
1013 
1014 #ifdef CONFIG_DEBUG_FS
1015 
1016 static int dw_mipi_dsi_debugfs_write(void *data, u64 val)
1017 {
1018 	struct debugfs_entries *vpg = data;
1019 	struct dw_mipi_dsi *dsi;
1020 	u32 mode_cfg;
1021 
1022 	if (!vpg)
1023 		return -ENODEV;
1024 
1025 	dsi = vpg->dsi;
1026 
1027 	*vpg->reg = (bool)val;
1028 
1029 	mode_cfg = dsi_read(dsi, DSI_VID_MODE_CFG);
1030 
1031 	if (*vpg->reg)
1032 		mode_cfg |= vpg->mask;
1033 	else
1034 		mode_cfg &= ~vpg->mask;
1035 
1036 	dsi_write(dsi, DSI_VID_MODE_CFG, mode_cfg);
1037 
1038 	return 0;
1039 }
1040 
1041 static int dw_mipi_dsi_debugfs_show(void *data, u64 *val)
1042 {
1043 	struct debugfs_entries *vpg = data;
1044 
1045 	if (!vpg)
1046 		return -ENODEV;
1047 
1048 	*val = *vpg->reg;
1049 
1050 	return 0;
1051 }
1052 
1053 DEFINE_DEBUGFS_ATTRIBUTE(fops_x32, dw_mipi_dsi_debugfs_show,
1054 			 dw_mipi_dsi_debugfs_write, "%llu\n");
1055 
1056 static void debugfs_create_files(void *data)
1057 {
1058 	struct dw_mipi_dsi *dsi = data;
1059 	struct debugfs_entries debugfs[] = {
1060 		REGISTER(vpg, VID_MODE_VPG_ENABLE, dsi),
1061 		REGISTER(vpg_horizontal, VID_MODE_VPG_HORIZONTAL, dsi),
1062 		REGISTER(vpg_ber_pattern, VID_MODE_VPG_MODE, dsi),
1063 	};
1064 	int i;
1065 
1066 	dsi->debugfs_vpg = kmemdup(debugfs, sizeof(debugfs), GFP_KERNEL);
1067 	if (!dsi->debugfs_vpg)
1068 		return;
1069 
1070 	for (i = 0; i < ARRAY_SIZE(debugfs); i++)
1071 		debugfs_create_file(dsi->debugfs_vpg[i].name, 0644,
1072 				    dsi->debugfs, &dsi->debugfs_vpg[i],
1073 				    &fops_x32);
1074 }
1075 
1076 static void dw_mipi_dsi_debugfs_init(struct dw_mipi_dsi *dsi)
1077 {
1078 	dsi->debugfs = debugfs_create_dir(dev_name(dsi->dev), NULL);
1079 	if (IS_ERR(dsi->debugfs)) {
1080 		dev_err(dsi->dev, "failed to create debugfs root\n");
1081 		return;
1082 	}
1083 
1084 	debugfs_create_files(dsi);
1085 }
1086 
1087 static void dw_mipi_dsi_debugfs_remove(struct dw_mipi_dsi *dsi)
1088 {
1089 	debugfs_remove_recursive(dsi->debugfs);
1090 	kfree(dsi->debugfs_vpg);
1091 }
1092 
1093 #else
1094 
1095 static void dw_mipi_dsi_debugfs_init(struct dw_mipi_dsi *dsi) { }
1096 static void dw_mipi_dsi_debugfs_remove(struct dw_mipi_dsi *dsi) { }
1097 
1098 #endif /* CONFIG_DEBUG_FS */
1099 
1100 static struct dw_mipi_dsi *
1101 __dw_mipi_dsi_probe(struct platform_device *pdev,
1102 		    const struct dw_mipi_dsi_plat_data *plat_data)
1103 {
1104 	struct device *dev = &pdev->dev;
1105 	struct reset_control *apb_rst;
1106 	struct dw_mipi_dsi *dsi;
1107 	int ret;
1108 
1109 	dsi = devm_kzalloc(dev, sizeof(*dsi), GFP_KERNEL);
1110 	if (!dsi)
1111 		return ERR_PTR(-ENOMEM);
1112 
1113 	dsi->dev = dev;
1114 	dsi->plat_data = plat_data;
1115 
1116 	if (!plat_data->phy_ops->init || !plat_data->phy_ops->get_lane_mbps ||
1117 	    !plat_data->phy_ops->get_timing) {
1118 		DRM_ERROR("Phy not properly configured\n");
1119 		return ERR_PTR(-ENODEV);
1120 	}
1121 
1122 	if (!plat_data->base) {
1123 		dsi->base = devm_platform_ioremap_resource(pdev, 0);
1124 		if (IS_ERR(dsi->base))
1125 			return ERR_PTR(-ENODEV);
1126 
1127 	} else {
1128 		dsi->base = plat_data->base;
1129 	}
1130 
1131 	dsi->pclk = devm_clk_get(dev, "pclk");
1132 	if (IS_ERR(dsi->pclk)) {
1133 		ret = PTR_ERR(dsi->pclk);
1134 		dev_err(dev, "Unable to get pclk: %d\n", ret);
1135 		return ERR_PTR(ret);
1136 	}
1137 
1138 	/*
1139 	 * Note that the reset was not defined in the initial device tree, so
1140 	 * we have to be prepared for it not being found.
1141 	 */
1142 	apb_rst = devm_reset_control_get_optional_exclusive(dev, "apb");
1143 	if (IS_ERR(apb_rst)) {
1144 		ret = PTR_ERR(apb_rst);
1145 
1146 		if (ret != -EPROBE_DEFER)
1147 			dev_err(dev, "Unable to get reset control: %d\n", ret);
1148 
1149 		return ERR_PTR(ret);
1150 	}
1151 
1152 	if (apb_rst) {
1153 		ret = clk_prepare_enable(dsi->pclk);
1154 		if (ret) {
1155 			dev_err(dev, "%s: Failed to enable pclk\n", __func__);
1156 			return ERR_PTR(ret);
1157 		}
1158 
1159 		reset_control_assert(apb_rst);
1160 		usleep_range(10, 20);
1161 		reset_control_deassert(apb_rst);
1162 
1163 		clk_disable_unprepare(dsi->pclk);
1164 	}
1165 
1166 	dw_mipi_dsi_debugfs_init(dsi);
1167 	pm_runtime_enable(dev);
1168 
1169 	dsi->dsi_host.ops = &dw_mipi_dsi_host_ops;
1170 	dsi->dsi_host.dev = dev;
1171 	ret = mipi_dsi_host_register(&dsi->dsi_host);
1172 	if (ret) {
1173 		dev_err(dev, "Failed to register MIPI host: %d\n", ret);
1174 		pm_runtime_disable(dev);
1175 		dw_mipi_dsi_debugfs_remove(dsi);
1176 		return ERR_PTR(ret);
1177 	}
1178 
1179 	dsi->bridge.driver_private = dsi;
1180 	dsi->bridge.funcs = &dw_mipi_dsi_bridge_funcs;
1181 #ifdef CONFIG_OF
1182 	dsi->bridge.of_node = pdev->dev.of_node;
1183 #endif
1184 
1185 	return dsi;
1186 }
1187 
1188 static void __dw_mipi_dsi_remove(struct dw_mipi_dsi *dsi)
1189 {
1190 	mipi_dsi_host_unregister(&dsi->dsi_host);
1191 
1192 	pm_runtime_disable(dsi->dev);
1193 	dw_mipi_dsi_debugfs_remove(dsi);
1194 }
1195 
1196 void dw_mipi_dsi_set_slave(struct dw_mipi_dsi *dsi, struct dw_mipi_dsi *slave)
1197 {
1198 	/* introduce controllers to each other */
1199 	dsi->slave = slave;
1200 	dsi->slave->master = dsi;
1201 
1202 	/* migrate settings for already attached displays */
1203 	dsi->slave->lanes = dsi->lanes;
1204 	dsi->slave->channel = dsi->channel;
1205 	dsi->slave->format = dsi->format;
1206 	dsi->slave->mode_flags = dsi->mode_flags;
1207 }
1208 EXPORT_SYMBOL_GPL(dw_mipi_dsi_set_slave);
1209 
1210 /*
1211  * Probe/remove API, used from platforms based on the DRM bridge API.
1212  */
1213 struct dw_mipi_dsi *
1214 dw_mipi_dsi_probe(struct platform_device *pdev,
1215 		  const struct dw_mipi_dsi_plat_data *plat_data)
1216 {
1217 	return __dw_mipi_dsi_probe(pdev, plat_data);
1218 }
1219 EXPORT_SYMBOL_GPL(dw_mipi_dsi_probe);
1220 
1221 void dw_mipi_dsi_remove(struct dw_mipi_dsi *dsi)
1222 {
1223 	__dw_mipi_dsi_remove(dsi);
1224 }
1225 EXPORT_SYMBOL_GPL(dw_mipi_dsi_remove);
1226 
1227 /*
1228  * Bind/unbind API, used from platforms based on the component framework.
1229  */
1230 int dw_mipi_dsi_bind(struct dw_mipi_dsi *dsi, struct drm_encoder *encoder)
1231 {
1232 	return drm_bridge_attach(encoder, &dsi->bridge, NULL, 0);
1233 }
1234 EXPORT_SYMBOL_GPL(dw_mipi_dsi_bind);
1235 
1236 void dw_mipi_dsi_unbind(struct dw_mipi_dsi *dsi)
1237 {
1238 }
1239 EXPORT_SYMBOL_GPL(dw_mipi_dsi_unbind);
1240 
1241 MODULE_AUTHOR("Chris Zhong <zyw@rock-chips.com>");
1242 MODULE_AUTHOR("Philippe Cornu <philippe.cornu@st.com>");
1243 MODULE_DESCRIPTION("DW MIPI DSI host controller driver");
1244 MODULE_LICENSE("GPL");
1245 MODULE_ALIAS("platform:dw-mipi-dsi");
1246