1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * TI SN65DSI83,84,85 driver
4  *
5  * Currently supported:
6  * - SN65DSI83
7  *   = 1x Single-link DSI ~ 1x Single-link LVDS
8  *   - Supported
9  *   - Single-link LVDS mode tested
10  * - SN65DSI84
11  *   = 1x Single-link DSI ~ 2x Single-link or 1x Dual-link LVDS
12  *   - Supported
13  *   - Dual-link LVDS mode tested
14  *   - 2x Single-link LVDS mode unsupported
15  *     (should be easy to add by someone who has the HW)
16  * - SN65DSI85
17  *   = 2x Single-link or 1x Dual-link DSI ~ 2x Single-link or 1x Dual-link LVDS
18  *   - Unsupported
19  *     (should be easy to add by someone who has the HW)
20  *
21  * Copyright (C) 2021 Marek Vasut <marex@denx.de>
22  *
23  * Based on previous work of:
24  * Valentin Raevsky <valentin@compulab.co.il>
25  * Philippe Schenker <philippe.schenker@toradex.com>
26  */
27 
28 #include <linux/bits.h>
29 #include <linux/clk.h>
30 #include <linux/gpio/consumer.h>
31 #include <linux/i2c.h>
32 #include <linux/module.h>
33 #include <linux/of_device.h>
34 #include <linux/of_graph.h>
35 #include <linux/regmap.h>
36 #include <linux/regulator/consumer.h>
37 
38 #include <drm/drm_atomic_helper.h>
39 #include <drm/drm_bridge.h>
40 #include <drm/drm_mipi_dsi.h>
41 #include <drm/drm_of.h>
42 #include <drm/drm_panel.h>
43 #include <drm/drm_print.h>
44 #include <drm/drm_probe_helper.h>
45 
46 /* ID registers */
47 #define REG_ID(n)				(0x00 + (n))
48 /* Reset and clock registers */
49 #define REG_RC_RESET				0x09
50 #define  REG_RC_RESET_SOFT_RESET		BIT(0)
51 #define REG_RC_LVDS_PLL				0x0a
52 #define  REG_RC_LVDS_PLL_PLL_EN_STAT		BIT(7)
53 #define  REG_RC_LVDS_PLL_LVDS_CLK_RANGE(n)	(((n) & 0x7) << 1)
54 #define  REG_RC_LVDS_PLL_HS_CLK_SRC_DPHY	BIT(0)
55 #define REG_RC_DSI_CLK				0x0b
56 #define  REG_RC_DSI_CLK_DSI_CLK_DIVIDER(n)	(((n) & 0x1f) << 3)
57 #define  REG_RC_DSI_CLK_REFCLK_MULTIPLIER(n)	((n) & 0x3)
58 #define REG_RC_PLL_EN				0x0d
59 #define  REG_RC_PLL_EN_PLL_EN			BIT(0)
60 /* DSI registers */
61 #define REG_DSI_LANE				0x10
62 #define  REG_DSI_LANE_LEFT_RIGHT_PIXELS		BIT(7)	/* DSI85-only */
63 #define  REG_DSI_LANE_DSI_CHANNEL_MODE_DUAL	0	/* DSI85-only */
64 #define  REG_DSI_LANE_DSI_CHANNEL_MODE_2SINGLE	BIT(6)	/* DSI85-only */
65 #define  REG_DSI_LANE_DSI_CHANNEL_MODE_SINGLE	BIT(5)
66 #define  REG_DSI_LANE_CHA_DSI_LANES(n)		(((n) & 0x3) << 3)
67 #define  REG_DSI_LANE_CHB_DSI_LANES(n)		(((n) & 0x3) << 1)
68 #define  REG_DSI_LANE_SOT_ERR_TOL_DIS		BIT(0)
69 #define REG_DSI_EQ				0x11
70 #define  REG_DSI_EQ_CHA_DSI_DATA_EQ(n)		(((n) & 0x3) << 6)
71 #define  REG_DSI_EQ_CHA_DSI_CLK_EQ(n)		(((n) & 0x3) << 2)
72 #define REG_DSI_CLK				0x12
73 #define  REG_DSI_CLK_CHA_DSI_CLK_RANGE(n)	((n) & 0xff)
74 /* LVDS registers */
75 #define REG_LVDS_FMT				0x18
76 #define  REG_LVDS_FMT_DE_NEG_POLARITY		BIT(7)
77 #define  REG_LVDS_FMT_HS_NEG_POLARITY		BIT(6)
78 #define  REG_LVDS_FMT_VS_NEG_POLARITY		BIT(5)
79 #define  REG_LVDS_FMT_LVDS_LINK_CFG		BIT(4)	/* 0:AB 1:A-only */
80 #define  REG_LVDS_FMT_CHA_24BPP_MODE		BIT(3)
81 #define  REG_LVDS_FMT_CHB_24BPP_MODE		BIT(2)
82 #define  REG_LVDS_FMT_CHA_24BPP_FORMAT1		BIT(1)
83 #define  REG_LVDS_FMT_CHB_24BPP_FORMAT1		BIT(0)
84 #define REG_LVDS_VCOM				0x19
85 #define  REG_LVDS_VCOM_CHA_LVDS_VOCM		BIT(6)
86 #define  REG_LVDS_VCOM_CHB_LVDS_VOCM		BIT(4)
87 #define  REG_LVDS_VCOM_CHA_LVDS_VOD_SWING(n)	(((n) & 0x3) << 2)
88 #define  REG_LVDS_VCOM_CHB_LVDS_VOD_SWING(n)	((n) & 0x3)
89 #define REG_LVDS_LANE				0x1a
90 #define  REG_LVDS_LANE_EVEN_ODD_SWAP		BIT(6)
91 #define  REG_LVDS_LANE_CHA_REVERSE_LVDS		BIT(5)
92 #define  REG_LVDS_LANE_CHB_REVERSE_LVDS		BIT(4)
93 #define  REG_LVDS_LANE_CHA_LVDS_TERM		BIT(1)
94 #define  REG_LVDS_LANE_CHB_LVDS_TERM		BIT(0)
95 #define REG_LVDS_CM				0x1b
96 #define  REG_LVDS_CM_CHA_LVDS_CM_ADJUST(n)	(((n) & 0x3) << 4)
97 #define  REG_LVDS_CM_CHB_LVDS_CM_ADJUST(n)	((n) & 0x3)
98 /* Video registers */
99 #define REG_VID_CHA_ACTIVE_LINE_LENGTH_LOW	0x20
100 #define REG_VID_CHA_ACTIVE_LINE_LENGTH_HIGH	0x21
101 #define REG_VID_CHA_VERTICAL_DISPLAY_SIZE_LOW	0x24
102 #define REG_VID_CHA_VERTICAL_DISPLAY_SIZE_HIGH	0x25
103 #define REG_VID_CHA_SYNC_DELAY_LOW		0x28
104 #define REG_VID_CHA_SYNC_DELAY_HIGH		0x29
105 #define REG_VID_CHA_HSYNC_PULSE_WIDTH_LOW	0x2c
106 #define REG_VID_CHA_HSYNC_PULSE_WIDTH_HIGH	0x2d
107 #define REG_VID_CHA_VSYNC_PULSE_WIDTH_LOW	0x30
108 #define REG_VID_CHA_VSYNC_PULSE_WIDTH_HIGH	0x31
109 #define REG_VID_CHA_HORIZONTAL_BACK_PORCH	0x34
110 #define REG_VID_CHA_VERTICAL_BACK_PORCH		0x36
111 #define REG_VID_CHA_HORIZONTAL_FRONT_PORCH	0x38
112 #define REG_VID_CHA_VERTICAL_FRONT_PORCH	0x3a
113 #define REG_VID_CHA_TEST_PATTERN		0x3c
114 /* IRQ registers */
115 #define REG_IRQ_GLOBAL				0xe0
116 #define  REG_IRQ_GLOBAL_IRQ_EN			BIT(0)
117 #define REG_IRQ_EN				0xe1
118 #define  REG_IRQ_EN_CHA_SYNCH_ERR_EN		BIT(7)
119 #define  REG_IRQ_EN_CHA_CRC_ERR_EN		BIT(6)
120 #define  REG_IRQ_EN_CHA_UNC_ECC_ERR_EN		BIT(5)
121 #define  REG_IRQ_EN_CHA_COR_ECC_ERR_EN		BIT(4)
122 #define  REG_IRQ_EN_CHA_LLP_ERR_EN		BIT(3)
123 #define  REG_IRQ_EN_CHA_SOT_BIT_ERR_EN		BIT(2)
124 #define  REG_IRQ_EN_CHA_PLL_UNLOCK_EN		BIT(0)
125 #define REG_IRQ_STAT				0xe5
126 #define  REG_IRQ_STAT_CHA_SYNCH_ERR		BIT(7)
127 #define  REG_IRQ_STAT_CHA_CRC_ERR		BIT(6)
128 #define  REG_IRQ_STAT_CHA_UNC_ECC_ERR		BIT(5)
129 #define  REG_IRQ_STAT_CHA_COR_ECC_ERR		BIT(4)
130 #define  REG_IRQ_STAT_CHA_LLP_ERR		BIT(3)
131 #define  REG_IRQ_STAT_CHA_SOT_BIT_ERR		BIT(2)
132 #define  REG_IRQ_STAT_CHA_PLL_UNLOCK		BIT(0)
133 
134 enum sn65dsi83_model {
135 	MODEL_SN65DSI83,
136 	MODEL_SN65DSI84,
137 };
138 
139 struct sn65dsi83 {
140 	struct drm_bridge		bridge;
141 	struct device			*dev;
142 	struct regmap			*regmap;
143 	struct device_node		*host_node;
144 	struct mipi_dsi_device		*dsi;
145 	struct drm_bridge		*panel_bridge;
146 	struct gpio_desc		*enable_gpio;
147 	struct regulator		*vcc;
148 	int				dsi_lanes;
149 	bool				lvds_dual_link;
150 	bool				lvds_dual_link_even_odd_swap;
151 };
152 
153 static const struct regmap_range sn65dsi83_readable_ranges[] = {
154 	regmap_reg_range(REG_ID(0), REG_ID(8)),
155 	regmap_reg_range(REG_RC_LVDS_PLL, REG_RC_DSI_CLK),
156 	regmap_reg_range(REG_RC_PLL_EN, REG_RC_PLL_EN),
157 	regmap_reg_range(REG_DSI_LANE, REG_DSI_CLK),
158 	regmap_reg_range(REG_LVDS_FMT, REG_LVDS_CM),
159 	regmap_reg_range(REG_VID_CHA_ACTIVE_LINE_LENGTH_LOW,
160 			 REG_VID_CHA_ACTIVE_LINE_LENGTH_HIGH),
161 	regmap_reg_range(REG_VID_CHA_VERTICAL_DISPLAY_SIZE_LOW,
162 			 REG_VID_CHA_VERTICAL_DISPLAY_SIZE_HIGH),
163 	regmap_reg_range(REG_VID_CHA_SYNC_DELAY_LOW,
164 			 REG_VID_CHA_SYNC_DELAY_HIGH),
165 	regmap_reg_range(REG_VID_CHA_HSYNC_PULSE_WIDTH_LOW,
166 			 REG_VID_CHA_HSYNC_PULSE_WIDTH_HIGH),
167 	regmap_reg_range(REG_VID_CHA_VSYNC_PULSE_WIDTH_LOW,
168 			 REG_VID_CHA_VSYNC_PULSE_WIDTH_HIGH),
169 	regmap_reg_range(REG_VID_CHA_HORIZONTAL_BACK_PORCH,
170 			 REG_VID_CHA_HORIZONTAL_BACK_PORCH),
171 	regmap_reg_range(REG_VID_CHA_VERTICAL_BACK_PORCH,
172 			 REG_VID_CHA_VERTICAL_BACK_PORCH),
173 	regmap_reg_range(REG_VID_CHA_HORIZONTAL_FRONT_PORCH,
174 			 REG_VID_CHA_HORIZONTAL_FRONT_PORCH),
175 	regmap_reg_range(REG_VID_CHA_VERTICAL_FRONT_PORCH,
176 			 REG_VID_CHA_VERTICAL_FRONT_PORCH),
177 	regmap_reg_range(REG_VID_CHA_TEST_PATTERN, REG_VID_CHA_TEST_PATTERN),
178 	regmap_reg_range(REG_IRQ_GLOBAL, REG_IRQ_EN),
179 	regmap_reg_range(REG_IRQ_STAT, REG_IRQ_STAT),
180 };
181 
182 static const struct regmap_access_table sn65dsi83_readable_table = {
183 	.yes_ranges = sn65dsi83_readable_ranges,
184 	.n_yes_ranges = ARRAY_SIZE(sn65dsi83_readable_ranges),
185 };
186 
187 static const struct regmap_range sn65dsi83_writeable_ranges[] = {
188 	regmap_reg_range(REG_RC_RESET, REG_RC_DSI_CLK),
189 	regmap_reg_range(REG_RC_PLL_EN, REG_RC_PLL_EN),
190 	regmap_reg_range(REG_DSI_LANE, REG_DSI_CLK),
191 	regmap_reg_range(REG_LVDS_FMT, REG_LVDS_CM),
192 	regmap_reg_range(REG_VID_CHA_ACTIVE_LINE_LENGTH_LOW,
193 			 REG_VID_CHA_ACTIVE_LINE_LENGTH_HIGH),
194 	regmap_reg_range(REG_VID_CHA_VERTICAL_DISPLAY_SIZE_LOW,
195 			 REG_VID_CHA_VERTICAL_DISPLAY_SIZE_HIGH),
196 	regmap_reg_range(REG_VID_CHA_SYNC_DELAY_LOW,
197 			 REG_VID_CHA_SYNC_DELAY_HIGH),
198 	regmap_reg_range(REG_VID_CHA_HSYNC_PULSE_WIDTH_LOW,
199 			 REG_VID_CHA_HSYNC_PULSE_WIDTH_HIGH),
200 	regmap_reg_range(REG_VID_CHA_VSYNC_PULSE_WIDTH_LOW,
201 			 REG_VID_CHA_VSYNC_PULSE_WIDTH_HIGH),
202 	regmap_reg_range(REG_VID_CHA_HORIZONTAL_BACK_PORCH,
203 			 REG_VID_CHA_HORIZONTAL_BACK_PORCH),
204 	regmap_reg_range(REG_VID_CHA_VERTICAL_BACK_PORCH,
205 			 REG_VID_CHA_VERTICAL_BACK_PORCH),
206 	regmap_reg_range(REG_VID_CHA_HORIZONTAL_FRONT_PORCH,
207 			 REG_VID_CHA_HORIZONTAL_FRONT_PORCH),
208 	regmap_reg_range(REG_VID_CHA_VERTICAL_FRONT_PORCH,
209 			 REG_VID_CHA_VERTICAL_FRONT_PORCH),
210 	regmap_reg_range(REG_VID_CHA_TEST_PATTERN, REG_VID_CHA_TEST_PATTERN),
211 	regmap_reg_range(REG_IRQ_GLOBAL, REG_IRQ_EN),
212 	regmap_reg_range(REG_IRQ_STAT, REG_IRQ_STAT),
213 };
214 
215 static const struct regmap_access_table sn65dsi83_writeable_table = {
216 	.yes_ranges = sn65dsi83_writeable_ranges,
217 	.n_yes_ranges = ARRAY_SIZE(sn65dsi83_writeable_ranges),
218 };
219 
220 static const struct regmap_range sn65dsi83_volatile_ranges[] = {
221 	regmap_reg_range(REG_RC_RESET, REG_RC_RESET),
222 	regmap_reg_range(REG_RC_LVDS_PLL, REG_RC_LVDS_PLL),
223 	regmap_reg_range(REG_IRQ_STAT, REG_IRQ_STAT),
224 };
225 
226 static const struct regmap_access_table sn65dsi83_volatile_table = {
227 	.yes_ranges = sn65dsi83_volatile_ranges,
228 	.n_yes_ranges = ARRAY_SIZE(sn65dsi83_volatile_ranges),
229 };
230 
231 static const struct regmap_config sn65dsi83_regmap_config = {
232 	.reg_bits = 8,
233 	.val_bits = 8,
234 	.rd_table = &sn65dsi83_readable_table,
235 	.wr_table = &sn65dsi83_writeable_table,
236 	.volatile_table = &sn65dsi83_volatile_table,
237 	.cache_type = REGCACHE_RBTREE,
238 	.max_register = REG_IRQ_STAT,
239 };
240 
241 static struct sn65dsi83 *bridge_to_sn65dsi83(struct drm_bridge *bridge)
242 {
243 	return container_of(bridge, struct sn65dsi83, bridge);
244 }
245 
246 static int sn65dsi83_attach(struct drm_bridge *bridge,
247 			    enum drm_bridge_attach_flags flags)
248 {
249 	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
250 
251 	return drm_bridge_attach(bridge->encoder, ctx->panel_bridge,
252 				 &ctx->bridge, flags);
253 }
254 
255 static void sn65dsi83_detach(struct drm_bridge *bridge)
256 {
257 	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
258 
259 	if (!ctx->dsi)
260 		return;
261 
262 	ctx->dsi = NULL;
263 }
264 
265 static u8 sn65dsi83_get_lvds_range(struct sn65dsi83 *ctx,
266 				   const struct drm_display_mode *mode)
267 {
268 	/*
269 	 * The encoding of the LVDS_CLK_RANGE is as follows:
270 	 * 000 - 25 MHz <= LVDS_CLK < 37.5 MHz
271 	 * 001 - 37.5 MHz <= LVDS_CLK < 62.5 MHz
272 	 * 010 - 62.5 MHz <= LVDS_CLK < 87.5 MHz
273 	 * 011 - 87.5 MHz <= LVDS_CLK < 112.5 MHz
274 	 * 100 - 112.5 MHz <= LVDS_CLK < 137.5 MHz
275 	 * 101 - 137.5 MHz <= LVDS_CLK <= 154 MHz
276 	 * which is a range of 12.5MHz..162.5MHz in 50MHz steps, except that
277 	 * the ends of the ranges are clamped to the supported range. Since
278 	 * sn65dsi83_mode_valid() already filters the valid modes and limits
279 	 * the clock to 25..154 MHz, the range calculation can be simplified
280 	 * as follows:
281 	 */
282 	int mode_clock = mode->clock;
283 
284 	if (ctx->lvds_dual_link)
285 		mode_clock /= 2;
286 
287 	return (mode_clock - 12500) / 25000;
288 }
289 
290 static u8 sn65dsi83_get_dsi_range(struct sn65dsi83 *ctx,
291 				  const struct drm_display_mode *mode)
292 {
293 	/*
294 	 * The encoding of the CHA_DSI_CLK_RANGE is as follows:
295 	 * 0x00 through 0x07 - Reserved
296 	 * 0x08 - 40 <= DSI_CLK < 45 MHz
297 	 * 0x09 - 45 <= DSI_CLK < 50 MHz
298 	 * ...
299 	 * 0x63 - 495 <= DSI_CLK < 500 MHz
300 	 * 0x64 - 500 MHz
301 	 * 0x65 through 0xFF - Reserved
302 	 * which is DSI clock in 5 MHz steps, clamped to 40..500 MHz.
303 	 * The DSI clock are calculated as:
304 	 *  DSI_CLK = mode clock * bpp / dsi_data_lanes / 2
305 	 * the 2 is there because the bus is DDR.
306 	 */
307 	return DIV_ROUND_UP(clamp((unsigned int)mode->clock *
308 			    mipi_dsi_pixel_format_to_bpp(ctx->dsi->format) /
309 			    ctx->dsi_lanes / 2, 40000U, 500000U), 5000U);
310 }
311 
312 static u8 sn65dsi83_get_dsi_div(struct sn65dsi83 *ctx)
313 {
314 	/* The divider is (DSI_CLK / LVDS_CLK) - 1, which really is: */
315 	unsigned int dsi_div = mipi_dsi_pixel_format_to_bpp(ctx->dsi->format);
316 
317 	dsi_div /= ctx->dsi_lanes;
318 
319 	if (!ctx->lvds_dual_link)
320 		dsi_div /= 2;
321 
322 	return dsi_div - 1;
323 }
324 
325 static void sn65dsi83_atomic_enable(struct drm_bridge *bridge,
326 				    struct drm_bridge_state *old_bridge_state)
327 {
328 	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
329 	struct drm_atomic_state *state = old_bridge_state->base.state;
330 	const struct drm_bridge_state *bridge_state;
331 	const struct drm_crtc_state *crtc_state;
332 	const struct drm_display_mode *mode;
333 	struct drm_connector *connector;
334 	struct drm_crtc *crtc;
335 	bool lvds_format_24bpp;
336 	bool lvds_format_jeida;
337 	unsigned int pval;
338 	__le16 le16val;
339 	u16 val;
340 	int ret;
341 
342 	ret = regulator_enable(ctx->vcc);
343 	if (ret) {
344 		dev_err(ctx->dev, "Failed to enable vcc: %d\n", ret);
345 		return;
346 	}
347 
348 	/* Deassert reset */
349 	gpiod_set_value(ctx->enable_gpio, 1);
350 	usleep_range(1000, 1100);
351 
352 	/* Get the LVDS format from the bridge state. */
353 	bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
354 
355 	switch (bridge_state->output_bus_cfg.format) {
356 	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
357 		lvds_format_24bpp = false;
358 		lvds_format_jeida = true;
359 		break;
360 	case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
361 		lvds_format_24bpp = true;
362 		lvds_format_jeida = true;
363 		break;
364 	case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
365 		lvds_format_24bpp = true;
366 		lvds_format_jeida = false;
367 		break;
368 	default:
369 		/*
370 		 * Some bridges still don't set the correct
371 		 * LVDS bus pixel format, use SPWG24 default
372 		 * format until those are fixed.
373 		 */
374 		lvds_format_24bpp = true;
375 		lvds_format_jeida = false;
376 		dev_warn(ctx->dev,
377 			 "Unsupported LVDS bus format 0x%04x, please check output bridge driver. Falling back to SPWG24.\n",
378 			 bridge_state->output_bus_cfg.format);
379 		break;
380 	}
381 
382 	/*
383 	 * Retrieve the CRTC adjusted mode. This requires a little dance to go
384 	 * from the bridge to the encoder, to the connector and to the CRTC.
385 	 */
386 	connector = drm_atomic_get_new_connector_for_encoder(state,
387 							     bridge->encoder);
388 	crtc = drm_atomic_get_new_connector_state(state, connector)->crtc;
389 	crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
390 	mode = &crtc_state->adjusted_mode;
391 
392 	/* Clear reset, disable PLL */
393 	regmap_write(ctx->regmap, REG_RC_RESET, 0x00);
394 	regmap_write(ctx->regmap, REG_RC_PLL_EN, 0x00);
395 
396 	/* Reference clock derived from DSI link clock. */
397 	regmap_write(ctx->regmap, REG_RC_LVDS_PLL,
398 		     REG_RC_LVDS_PLL_LVDS_CLK_RANGE(sn65dsi83_get_lvds_range(ctx, mode)) |
399 		     REG_RC_LVDS_PLL_HS_CLK_SRC_DPHY);
400 	regmap_write(ctx->regmap, REG_DSI_CLK,
401 		     REG_DSI_CLK_CHA_DSI_CLK_RANGE(sn65dsi83_get_dsi_range(ctx, mode)));
402 	regmap_write(ctx->regmap, REG_RC_DSI_CLK,
403 		     REG_RC_DSI_CLK_DSI_CLK_DIVIDER(sn65dsi83_get_dsi_div(ctx)));
404 
405 	/* Set number of DSI lanes and LVDS link config. */
406 	regmap_write(ctx->regmap, REG_DSI_LANE,
407 		     REG_DSI_LANE_DSI_CHANNEL_MODE_SINGLE |
408 		     REG_DSI_LANE_CHA_DSI_LANES(~(ctx->dsi_lanes - 1)) |
409 		     /* CHB is DSI85-only, set to default on DSI83/DSI84 */
410 		     REG_DSI_LANE_CHB_DSI_LANES(3));
411 	/* No equalization. */
412 	regmap_write(ctx->regmap, REG_DSI_EQ, 0x00);
413 
414 	/* Set up sync signal polarity. */
415 	val = (mode->flags & DRM_MODE_FLAG_NHSYNC ?
416 	       REG_LVDS_FMT_HS_NEG_POLARITY : 0) |
417 	      (mode->flags & DRM_MODE_FLAG_NVSYNC ?
418 	       REG_LVDS_FMT_VS_NEG_POLARITY : 0);
419 
420 	/* Set up bits-per-pixel, 18bpp or 24bpp. */
421 	if (lvds_format_24bpp) {
422 		val |= REG_LVDS_FMT_CHA_24BPP_MODE;
423 		if (ctx->lvds_dual_link)
424 			val |= REG_LVDS_FMT_CHB_24BPP_MODE;
425 	}
426 
427 	/* Set up LVDS format, JEIDA/Format 1 or SPWG/Format 2 */
428 	if (lvds_format_jeida) {
429 		val |= REG_LVDS_FMT_CHA_24BPP_FORMAT1;
430 		if (ctx->lvds_dual_link)
431 			val |= REG_LVDS_FMT_CHB_24BPP_FORMAT1;
432 	}
433 
434 	/* Set up LVDS output config (DSI84,DSI85) */
435 	if (!ctx->lvds_dual_link)
436 		val |= REG_LVDS_FMT_LVDS_LINK_CFG;
437 
438 	regmap_write(ctx->regmap, REG_LVDS_FMT, val);
439 	regmap_write(ctx->regmap, REG_LVDS_VCOM, 0x05);
440 	regmap_write(ctx->regmap, REG_LVDS_LANE,
441 		     (ctx->lvds_dual_link_even_odd_swap ?
442 		      REG_LVDS_LANE_EVEN_ODD_SWAP : 0) |
443 		     REG_LVDS_LANE_CHA_LVDS_TERM |
444 		     REG_LVDS_LANE_CHB_LVDS_TERM);
445 	regmap_write(ctx->regmap, REG_LVDS_CM, 0x00);
446 
447 	le16val = cpu_to_le16(mode->hdisplay);
448 	regmap_bulk_write(ctx->regmap, REG_VID_CHA_ACTIVE_LINE_LENGTH_LOW,
449 			  &le16val, 2);
450 	le16val = cpu_to_le16(mode->vdisplay);
451 	regmap_bulk_write(ctx->regmap, REG_VID_CHA_VERTICAL_DISPLAY_SIZE_LOW,
452 			  &le16val, 2);
453 	/* 32 + 1 pixel clock to ensure proper operation */
454 	le16val = cpu_to_le16(32 + 1);
455 	regmap_bulk_write(ctx->regmap, REG_VID_CHA_SYNC_DELAY_LOW, &le16val, 2);
456 	le16val = cpu_to_le16(mode->hsync_end - mode->hsync_start);
457 	regmap_bulk_write(ctx->regmap, REG_VID_CHA_HSYNC_PULSE_WIDTH_LOW,
458 			  &le16val, 2);
459 	le16val = cpu_to_le16(mode->vsync_end - mode->vsync_start);
460 	regmap_bulk_write(ctx->regmap, REG_VID_CHA_VSYNC_PULSE_WIDTH_LOW,
461 			  &le16val, 2);
462 	regmap_write(ctx->regmap, REG_VID_CHA_HORIZONTAL_BACK_PORCH,
463 		     mode->htotal - mode->hsync_end);
464 	regmap_write(ctx->regmap, REG_VID_CHA_VERTICAL_BACK_PORCH,
465 		     mode->vtotal - mode->vsync_end);
466 	regmap_write(ctx->regmap, REG_VID_CHA_HORIZONTAL_FRONT_PORCH,
467 		     mode->hsync_start - mode->hdisplay);
468 	regmap_write(ctx->regmap, REG_VID_CHA_VERTICAL_FRONT_PORCH,
469 		     mode->vsync_start - mode->vdisplay);
470 	regmap_write(ctx->regmap, REG_VID_CHA_TEST_PATTERN, 0x00);
471 
472 	/* Enable PLL */
473 	regmap_write(ctx->regmap, REG_RC_PLL_EN, REG_RC_PLL_EN_PLL_EN);
474 	usleep_range(3000, 4000);
475 	ret = regmap_read_poll_timeout(ctx->regmap, REG_RC_LVDS_PLL, pval,
476 				       pval & REG_RC_LVDS_PLL_PLL_EN_STAT,
477 				       1000, 100000);
478 	if (ret) {
479 		dev_err(ctx->dev, "failed to lock PLL, ret=%i\n", ret);
480 		/* On failure, disable PLL again and exit. */
481 		regmap_write(ctx->regmap, REG_RC_PLL_EN, 0x00);
482 		return;
483 	}
484 
485 	/* Trigger reset after CSR register update. */
486 	regmap_write(ctx->regmap, REG_RC_RESET, REG_RC_RESET_SOFT_RESET);
487 
488 	/* Clear all errors that got asserted during initialization. */
489 	regmap_read(ctx->regmap, REG_IRQ_STAT, &pval);
490 	regmap_write(ctx->regmap, REG_IRQ_STAT, pval);
491 
492 	usleep_range(10000, 12000);
493 	regmap_read(ctx->regmap, REG_IRQ_STAT, &pval);
494 	if (pval)
495 		dev_err(ctx->dev, "Unexpected link status 0x%02x\n", pval);
496 }
497 
498 static void sn65dsi83_atomic_disable(struct drm_bridge *bridge,
499 				     struct drm_bridge_state *old_bridge_state)
500 {
501 	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
502 	int ret;
503 
504 	/* Put the chip in reset, pull EN line low, and assure 10ms reset low timing. */
505 	gpiod_set_value(ctx->enable_gpio, 0);
506 	usleep_range(10000, 11000);
507 
508 	ret = regulator_disable(ctx->vcc);
509 	if (ret)
510 		dev_err(ctx->dev, "Failed to disable vcc: %d\n", ret);
511 
512 	regcache_mark_dirty(ctx->regmap);
513 }
514 
515 static enum drm_mode_status
516 sn65dsi83_mode_valid(struct drm_bridge *bridge,
517 		     const struct drm_display_info *info,
518 		     const struct drm_display_mode *mode)
519 {
520 	/* LVDS output clock range 25..154 MHz */
521 	if (mode->clock < 25000)
522 		return MODE_CLOCK_LOW;
523 	if (mode->clock > 154000)
524 		return MODE_CLOCK_HIGH;
525 
526 	return MODE_OK;
527 }
528 
529 #define MAX_INPUT_SEL_FORMATS	1
530 
531 static u32 *
532 sn65dsi83_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
533 				    struct drm_bridge_state *bridge_state,
534 				    struct drm_crtc_state *crtc_state,
535 				    struct drm_connector_state *conn_state,
536 				    u32 output_fmt,
537 				    unsigned int *num_input_fmts)
538 {
539 	u32 *input_fmts;
540 
541 	*num_input_fmts = 0;
542 
543 	input_fmts = kcalloc(MAX_INPUT_SEL_FORMATS, sizeof(*input_fmts),
544 			     GFP_KERNEL);
545 	if (!input_fmts)
546 		return NULL;
547 
548 	/* This is the DSI-end bus format */
549 	input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X24;
550 	*num_input_fmts = 1;
551 
552 	return input_fmts;
553 }
554 
555 static const struct drm_bridge_funcs sn65dsi83_funcs = {
556 	.attach			= sn65dsi83_attach,
557 	.detach			= sn65dsi83_detach,
558 	.atomic_enable		= sn65dsi83_atomic_enable,
559 	.atomic_disable		= sn65dsi83_atomic_disable,
560 	.mode_valid		= sn65dsi83_mode_valid,
561 
562 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
563 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
564 	.atomic_reset = drm_atomic_helper_bridge_reset,
565 	.atomic_get_input_bus_fmts = sn65dsi83_atomic_get_input_bus_fmts,
566 };
567 
568 static int sn65dsi83_parse_dt(struct sn65dsi83 *ctx, enum sn65dsi83_model model)
569 {
570 	struct drm_bridge *panel_bridge;
571 	struct device *dev = ctx->dev;
572 	struct device_node *endpoint;
573 	int ret;
574 
575 	endpoint = of_graph_get_endpoint_by_regs(dev->of_node, 0, 0);
576 	ctx->dsi_lanes = of_property_count_u32_elems(endpoint, "data-lanes");
577 	ctx->host_node = of_graph_get_remote_port_parent(endpoint);
578 	of_node_put(endpoint);
579 
580 	if (ctx->dsi_lanes <= 0 || ctx->dsi_lanes > 4) {
581 		ret = -EINVAL;
582 		goto err_put_node;
583 	}
584 	if (!ctx->host_node) {
585 		ret = -ENODEV;
586 		goto err_put_node;
587 	}
588 
589 	ctx->lvds_dual_link = false;
590 	ctx->lvds_dual_link_even_odd_swap = false;
591 	if (model != MODEL_SN65DSI83) {
592 		struct device_node *port2, *port3;
593 		int dual_link;
594 
595 		port2 = of_graph_get_port_by_id(dev->of_node, 2);
596 		port3 = of_graph_get_port_by_id(dev->of_node, 3);
597 		dual_link = drm_of_lvds_get_dual_link_pixel_order(port2, port3);
598 		of_node_put(port2);
599 		of_node_put(port3);
600 
601 		if (dual_link == DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS) {
602 			ctx->lvds_dual_link = true;
603 			/* Odd pixels to LVDS Channel A, even pixels to B */
604 			ctx->lvds_dual_link_even_odd_swap = false;
605 		} else if (dual_link == DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS) {
606 			ctx->lvds_dual_link = true;
607 			/* Even pixels to LVDS Channel A, odd pixels to B */
608 			ctx->lvds_dual_link_even_odd_swap = true;
609 		}
610 	}
611 
612 	panel_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 2, 0);
613 	if (IS_ERR(panel_bridge)) {
614 		ret = PTR_ERR(panel_bridge);
615 		goto err_put_node;
616 	}
617 
618 	ctx->panel_bridge = panel_bridge;
619 
620 	ctx->vcc = devm_regulator_get(dev, "vcc");
621 	if (IS_ERR(ctx->vcc))
622 		return dev_err_probe(dev, PTR_ERR(ctx->vcc),
623 				     "Failed to get supply 'vcc'\n");
624 
625 	return 0;
626 
627 err_put_node:
628 	of_node_put(ctx->host_node);
629 	return ret;
630 }
631 
632 static int sn65dsi83_host_attach(struct sn65dsi83 *ctx)
633 {
634 	struct device *dev = ctx->dev;
635 	struct mipi_dsi_device *dsi;
636 	struct mipi_dsi_host *host;
637 	const struct mipi_dsi_device_info info = {
638 		.type = "sn65dsi83",
639 		.channel = 0,
640 		.node = NULL,
641 	};
642 	int ret;
643 
644 	host = of_find_mipi_dsi_host_by_node(ctx->host_node);
645 	if (!host) {
646 		dev_err(dev, "failed to find dsi host\n");
647 		return -EPROBE_DEFER;
648 	}
649 
650 	dsi = devm_mipi_dsi_device_register_full(dev, host, &info);
651 	if (IS_ERR(dsi))
652 		return dev_err_probe(dev, PTR_ERR(dsi),
653 				     "failed to create dsi device\n");
654 
655 	ctx->dsi = dsi;
656 
657 	dsi->lanes = ctx->dsi_lanes;
658 	dsi->format = MIPI_DSI_FMT_RGB888;
659 	dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST;
660 
661 	ret = devm_mipi_dsi_attach(dev, dsi);
662 	if (ret < 0) {
663 		dev_err(dev, "failed to attach dsi to host: %d\n", ret);
664 		return ret;
665 	}
666 
667 	return 0;
668 }
669 
670 static int sn65dsi83_probe(struct i2c_client *client,
671 			   const struct i2c_device_id *id)
672 {
673 	struct device *dev = &client->dev;
674 	enum sn65dsi83_model model;
675 	struct sn65dsi83 *ctx;
676 	int ret;
677 
678 	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
679 	if (!ctx)
680 		return -ENOMEM;
681 
682 	ctx->dev = dev;
683 
684 	if (dev->of_node) {
685 		model = (enum sn65dsi83_model)(uintptr_t)
686 			of_device_get_match_data(dev);
687 	} else {
688 		model = id->driver_data;
689 	}
690 
691 	/* Put the chip in reset, pull EN line low, and assure 10ms reset low timing. */
692 	ctx->enable_gpio = devm_gpiod_get_optional(ctx->dev, "enable",
693 						   GPIOD_OUT_LOW);
694 	if (IS_ERR(ctx->enable_gpio))
695 		return PTR_ERR(ctx->enable_gpio);
696 
697 	usleep_range(10000, 11000);
698 
699 	ret = sn65dsi83_parse_dt(ctx, model);
700 	if (ret)
701 		return ret;
702 
703 	ctx->regmap = devm_regmap_init_i2c(client, &sn65dsi83_regmap_config);
704 	if (IS_ERR(ctx->regmap)) {
705 		ret = PTR_ERR(ctx->regmap);
706 		goto err_put_node;
707 	}
708 
709 	dev_set_drvdata(dev, ctx);
710 	i2c_set_clientdata(client, ctx);
711 
712 	ctx->bridge.funcs = &sn65dsi83_funcs;
713 	ctx->bridge.of_node = dev->of_node;
714 	drm_bridge_add(&ctx->bridge);
715 
716 	ret = sn65dsi83_host_attach(ctx);
717 	if (ret)
718 		goto err_remove_bridge;
719 
720 	return 0;
721 
722 err_remove_bridge:
723 	drm_bridge_remove(&ctx->bridge);
724 err_put_node:
725 	of_node_put(ctx->host_node);
726 	return ret;
727 }
728 
729 static int sn65dsi83_remove(struct i2c_client *client)
730 {
731 	struct sn65dsi83 *ctx = i2c_get_clientdata(client);
732 
733 	drm_bridge_remove(&ctx->bridge);
734 	of_node_put(ctx->host_node);
735 
736 	return 0;
737 }
738 
739 static struct i2c_device_id sn65dsi83_id[] = {
740 	{ "ti,sn65dsi83", MODEL_SN65DSI83 },
741 	{ "ti,sn65dsi84", MODEL_SN65DSI84 },
742 	{},
743 };
744 MODULE_DEVICE_TABLE(i2c, sn65dsi83_id);
745 
746 static const struct of_device_id sn65dsi83_match_table[] = {
747 	{ .compatible = "ti,sn65dsi83", .data = (void *)MODEL_SN65DSI83 },
748 	{ .compatible = "ti,sn65dsi84", .data = (void *)MODEL_SN65DSI84 },
749 	{},
750 };
751 MODULE_DEVICE_TABLE(of, sn65dsi83_match_table);
752 
753 static struct i2c_driver sn65dsi83_driver = {
754 	.probe = sn65dsi83_probe,
755 	.remove = sn65dsi83_remove,
756 	.id_table = sn65dsi83_id,
757 	.driver = {
758 		.name = "sn65dsi83",
759 		.of_match_table = sn65dsi83_match_table,
760 	},
761 };
762 module_i2c_driver(sn65dsi83_driver);
763 
764 MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
765 MODULE_DESCRIPTION("TI SN65DSI83 DSI to LVDS bridge driver");
766 MODULE_LICENSE("GPL v2");
767