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