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 drm_display_mode		mode;
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 	int				dsi_lanes;
148 	bool				lvds_dual_link;
149 	bool				lvds_dual_link_even_odd_swap;
150 	bool				lvds_format_24bpp;
151 	bool				lvds_format_jeida;
152 };
153 
154 static const struct regmap_range sn65dsi83_readable_ranges[] = {
155 	regmap_reg_range(REG_ID(0), REG_ID(8)),
156 	regmap_reg_range(REG_RC_LVDS_PLL, REG_RC_DSI_CLK),
157 	regmap_reg_range(REG_RC_PLL_EN, REG_RC_PLL_EN),
158 	regmap_reg_range(REG_DSI_LANE, REG_DSI_CLK),
159 	regmap_reg_range(REG_LVDS_FMT, REG_LVDS_CM),
160 	regmap_reg_range(REG_VID_CHA_ACTIVE_LINE_LENGTH_LOW,
161 			 REG_VID_CHA_ACTIVE_LINE_LENGTH_HIGH),
162 	regmap_reg_range(REG_VID_CHA_VERTICAL_DISPLAY_SIZE_LOW,
163 			 REG_VID_CHA_VERTICAL_DISPLAY_SIZE_HIGH),
164 	regmap_reg_range(REG_VID_CHA_SYNC_DELAY_LOW,
165 			 REG_VID_CHA_SYNC_DELAY_HIGH),
166 	regmap_reg_range(REG_VID_CHA_HSYNC_PULSE_WIDTH_LOW,
167 			 REG_VID_CHA_HSYNC_PULSE_WIDTH_HIGH),
168 	regmap_reg_range(REG_VID_CHA_VSYNC_PULSE_WIDTH_LOW,
169 			 REG_VID_CHA_VSYNC_PULSE_WIDTH_HIGH),
170 	regmap_reg_range(REG_VID_CHA_HORIZONTAL_BACK_PORCH,
171 			 REG_VID_CHA_HORIZONTAL_BACK_PORCH),
172 	regmap_reg_range(REG_VID_CHA_VERTICAL_BACK_PORCH,
173 			 REG_VID_CHA_VERTICAL_BACK_PORCH),
174 	regmap_reg_range(REG_VID_CHA_HORIZONTAL_FRONT_PORCH,
175 			 REG_VID_CHA_HORIZONTAL_FRONT_PORCH),
176 	regmap_reg_range(REG_VID_CHA_VERTICAL_FRONT_PORCH,
177 			 REG_VID_CHA_VERTICAL_FRONT_PORCH),
178 	regmap_reg_range(REG_VID_CHA_TEST_PATTERN, REG_VID_CHA_TEST_PATTERN),
179 	regmap_reg_range(REG_IRQ_GLOBAL, REG_IRQ_EN),
180 	regmap_reg_range(REG_IRQ_STAT, REG_IRQ_STAT),
181 };
182 
183 static const struct regmap_access_table sn65dsi83_readable_table = {
184 	.yes_ranges = sn65dsi83_readable_ranges,
185 	.n_yes_ranges = ARRAY_SIZE(sn65dsi83_readable_ranges),
186 };
187 
188 static const struct regmap_range sn65dsi83_writeable_ranges[] = {
189 	regmap_reg_range(REG_RC_RESET, REG_RC_DSI_CLK),
190 	regmap_reg_range(REG_RC_PLL_EN, REG_RC_PLL_EN),
191 	regmap_reg_range(REG_DSI_LANE, REG_DSI_CLK),
192 	regmap_reg_range(REG_LVDS_FMT, REG_LVDS_CM),
193 	regmap_reg_range(REG_VID_CHA_ACTIVE_LINE_LENGTH_LOW,
194 			 REG_VID_CHA_ACTIVE_LINE_LENGTH_HIGH),
195 	regmap_reg_range(REG_VID_CHA_VERTICAL_DISPLAY_SIZE_LOW,
196 			 REG_VID_CHA_VERTICAL_DISPLAY_SIZE_HIGH),
197 	regmap_reg_range(REG_VID_CHA_SYNC_DELAY_LOW,
198 			 REG_VID_CHA_SYNC_DELAY_HIGH),
199 	regmap_reg_range(REG_VID_CHA_HSYNC_PULSE_WIDTH_LOW,
200 			 REG_VID_CHA_HSYNC_PULSE_WIDTH_HIGH),
201 	regmap_reg_range(REG_VID_CHA_VSYNC_PULSE_WIDTH_LOW,
202 			 REG_VID_CHA_VSYNC_PULSE_WIDTH_HIGH),
203 	regmap_reg_range(REG_VID_CHA_HORIZONTAL_BACK_PORCH,
204 			 REG_VID_CHA_HORIZONTAL_BACK_PORCH),
205 	regmap_reg_range(REG_VID_CHA_VERTICAL_BACK_PORCH,
206 			 REG_VID_CHA_VERTICAL_BACK_PORCH),
207 	regmap_reg_range(REG_VID_CHA_HORIZONTAL_FRONT_PORCH,
208 			 REG_VID_CHA_HORIZONTAL_FRONT_PORCH),
209 	regmap_reg_range(REG_VID_CHA_VERTICAL_FRONT_PORCH,
210 			 REG_VID_CHA_VERTICAL_FRONT_PORCH),
211 	regmap_reg_range(REG_VID_CHA_TEST_PATTERN, REG_VID_CHA_TEST_PATTERN),
212 	regmap_reg_range(REG_IRQ_GLOBAL, REG_IRQ_EN),
213 	regmap_reg_range(REG_IRQ_STAT, REG_IRQ_STAT),
214 };
215 
216 static const struct regmap_access_table sn65dsi83_writeable_table = {
217 	.yes_ranges = sn65dsi83_writeable_ranges,
218 	.n_yes_ranges = ARRAY_SIZE(sn65dsi83_writeable_ranges),
219 };
220 
221 static const struct regmap_range sn65dsi83_volatile_ranges[] = {
222 	regmap_reg_range(REG_RC_RESET, REG_RC_RESET),
223 	regmap_reg_range(REG_RC_LVDS_PLL, REG_RC_LVDS_PLL),
224 	regmap_reg_range(REG_IRQ_STAT, REG_IRQ_STAT),
225 };
226 
227 static const struct regmap_access_table sn65dsi83_volatile_table = {
228 	.yes_ranges = sn65dsi83_volatile_ranges,
229 	.n_yes_ranges = ARRAY_SIZE(sn65dsi83_volatile_ranges),
230 };
231 
232 static const struct regmap_config sn65dsi83_regmap_config = {
233 	.reg_bits = 8,
234 	.val_bits = 8,
235 	.rd_table = &sn65dsi83_readable_table,
236 	.wr_table = &sn65dsi83_writeable_table,
237 	.volatile_table = &sn65dsi83_volatile_table,
238 	.cache_type = REGCACHE_RBTREE,
239 	.max_register = REG_IRQ_STAT,
240 };
241 
242 static struct sn65dsi83 *bridge_to_sn65dsi83(struct drm_bridge *bridge)
243 {
244 	return container_of(bridge, struct sn65dsi83, bridge);
245 }
246 
247 static int sn65dsi83_attach(struct drm_bridge *bridge,
248 			    enum drm_bridge_attach_flags flags)
249 {
250 	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
251 	struct device *dev = ctx->dev;
252 	struct mipi_dsi_device *dsi;
253 	struct mipi_dsi_host *host;
254 	int ret = 0;
255 
256 	const struct mipi_dsi_device_info info = {
257 		.type = "sn65dsi83",
258 		.channel = 0,
259 		.node = NULL,
260 	};
261 
262 	host = of_find_mipi_dsi_host_by_node(ctx->host_node);
263 	if (!host) {
264 		dev_err(dev, "failed to find dsi host\n");
265 		return -EPROBE_DEFER;
266 	}
267 
268 	dsi = mipi_dsi_device_register_full(host, &info);
269 	if (IS_ERR(dsi)) {
270 		return dev_err_probe(dev, PTR_ERR(dsi),
271 				     "failed to create dsi device\n");
272 	}
273 
274 	ctx->dsi = dsi;
275 
276 	dsi->lanes = ctx->dsi_lanes;
277 	dsi->format = MIPI_DSI_FMT_RGB888;
278 	dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST;
279 
280 	ret = mipi_dsi_attach(dsi);
281 	if (ret < 0) {
282 		dev_err(dev, "failed to attach dsi to host\n");
283 		goto err_dsi_attach;
284 	}
285 
286 	return drm_bridge_attach(bridge->encoder, ctx->panel_bridge,
287 				 &ctx->bridge, flags);
288 
289 err_dsi_attach:
290 	mipi_dsi_device_unregister(dsi);
291 	return ret;
292 }
293 
294 static void sn65dsi83_pre_enable(struct drm_bridge *bridge)
295 {
296 	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
297 
298 	/*
299 	 * Reset the chip, pull EN line low for t_reset=10ms,
300 	 * then high for t_en=1ms.
301 	 */
302 	regcache_mark_dirty(ctx->regmap);
303 	gpiod_set_value(ctx->enable_gpio, 0);
304 	usleep_range(10000, 11000);
305 	gpiod_set_value(ctx->enable_gpio, 1);
306 	usleep_range(1000, 1100);
307 }
308 
309 static u8 sn65dsi83_get_lvds_range(struct sn65dsi83 *ctx)
310 {
311 	/*
312 	 * The encoding of the LVDS_CLK_RANGE is as follows:
313 	 * 000 - 25 MHz <= LVDS_CLK < 37.5 MHz
314 	 * 001 - 37.5 MHz <= LVDS_CLK < 62.5 MHz
315 	 * 010 - 62.5 MHz <= LVDS_CLK < 87.5 MHz
316 	 * 011 - 87.5 MHz <= LVDS_CLK < 112.5 MHz
317 	 * 100 - 112.5 MHz <= LVDS_CLK < 137.5 MHz
318 	 * 101 - 137.5 MHz <= LVDS_CLK <= 154 MHz
319 	 * which is a range of 12.5MHz..162.5MHz in 50MHz steps, except that
320 	 * the ends of the ranges are clamped to the supported range. Since
321 	 * sn65dsi83_mode_valid() already filters the valid modes and limits
322 	 * the clock to 25..154 MHz, the range calculation can be simplified
323 	 * as follows:
324 	 */
325 	int mode_clock = ctx->mode.clock;
326 
327 	if (ctx->lvds_dual_link)
328 		mode_clock /= 2;
329 
330 	return (mode_clock - 12500) / 25000;
331 }
332 
333 static u8 sn65dsi83_get_dsi_range(struct sn65dsi83 *ctx)
334 {
335 	/*
336 	 * The encoding of the CHA_DSI_CLK_RANGE is as follows:
337 	 * 0x00 through 0x07 - Reserved
338 	 * 0x08 - 40 <= DSI_CLK < 45 MHz
339 	 * 0x09 - 45 <= DSI_CLK < 50 MHz
340 	 * ...
341 	 * 0x63 - 495 <= DSI_CLK < 500 MHz
342 	 * 0x64 - 500 MHz
343 	 * 0x65 through 0xFF - Reserved
344 	 * which is DSI clock in 5 MHz steps, clamped to 40..500 MHz.
345 	 * The DSI clock are calculated as:
346 	 *  DSI_CLK = mode clock * bpp / dsi_data_lanes / 2
347 	 * the 2 is there because the bus is DDR.
348 	 */
349 	return DIV_ROUND_UP(clamp((unsigned int)ctx->mode.clock *
350 			    mipi_dsi_pixel_format_to_bpp(ctx->dsi->format) /
351 			    ctx->dsi_lanes / 2, 40000U, 500000U), 5000U);
352 }
353 
354 static u8 sn65dsi83_get_dsi_div(struct sn65dsi83 *ctx)
355 {
356 	/* The divider is (DSI_CLK / LVDS_CLK) - 1, which really is: */
357 	unsigned int dsi_div = mipi_dsi_pixel_format_to_bpp(ctx->dsi->format);
358 
359 	dsi_div /= ctx->dsi_lanes;
360 
361 	if (!ctx->lvds_dual_link)
362 		dsi_div /= 2;
363 
364 	return dsi_div - 1;
365 }
366 
367 static void sn65dsi83_enable(struct drm_bridge *bridge)
368 {
369 	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
370 	unsigned int pval;
371 	u16 val;
372 	int ret;
373 
374 	/* Clear reset, disable PLL */
375 	regmap_write(ctx->regmap, REG_RC_RESET, 0x00);
376 	regmap_write(ctx->regmap, REG_RC_PLL_EN, 0x00);
377 
378 	/* Reference clock derived from DSI link clock. */
379 	regmap_write(ctx->regmap, REG_RC_LVDS_PLL,
380 		     REG_RC_LVDS_PLL_LVDS_CLK_RANGE(sn65dsi83_get_lvds_range(ctx)) |
381 		     REG_RC_LVDS_PLL_HS_CLK_SRC_DPHY);
382 	regmap_write(ctx->regmap, REG_DSI_CLK,
383 		     REG_DSI_CLK_CHA_DSI_CLK_RANGE(sn65dsi83_get_dsi_range(ctx)));
384 	regmap_write(ctx->regmap, REG_RC_DSI_CLK,
385 		     REG_RC_DSI_CLK_DSI_CLK_DIVIDER(sn65dsi83_get_dsi_div(ctx)));
386 
387 	/* Set number of DSI lanes and LVDS link config. */
388 	regmap_write(ctx->regmap, REG_DSI_LANE,
389 		     REG_DSI_LANE_DSI_CHANNEL_MODE_SINGLE |
390 		     REG_DSI_LANE_CHA_DSI_LANES(~(ctx->dsi_lanes - 1)) |
391 		     /* CHB is DSI85-only, set to default on DSI83/DSI84 */
392 		     REG_DSI_LANE_CHB_DSI_LANES(3));
393 	/* No equalization. */
394 	regmap_write(ctx->regmap, REG_DSI_EQ, 0x00);
395 
396 	/* Set up sync signal polarity. */
397 	val = (ctx->mode.flags & DRM_MODE_FLAG_NHSYNC ?
398 	       REG_LVDS_FMT_HS_NEG_POLARITY : 0) |
399 	      (ctx->mode.flags & DRM_MODE_FLAG_NVSYNC ?
400 	       REG_LVDS_FMT_VS_NEG_POLARITY : 0);
401 
402 	/* Set up bits-per-pixel, 18bpp or 24bpp. */
403 	if (ctx->lvds_format_24bpp) {
404 		val |= REG_LVDS_FMT_CHA_24BPP_MODE;
405 		if (ctx->lvds_dual_link)
406 			val |= REG_LVDS_FMT_CHB_24BPP_MODE;
407 	}
408 
409 	/* Set up LVDS format, JEIDA/Format 1 or SPWG/Format 2 */
410 	if (ctx->lvds_format_jeida) {
411 		val |= REG_LVDS_FMT_CHA_24BPP_FORMAT1;
412 		if (ctx->lvds_dual_link)
413 			val |= REG_LVDS_FMT_CHB_24BPP_FORMAT1;
414 	}
415 
416 	/* Set up LVDS output config (DSI84,DSI85) */
417 	if (!ctx->lvds_dual_link)
418 		val |= REG_LVDS_FMT_LVDS_LINK_CFG;
419 
420 	regmap_write(ctx->regmap, REG_LVDS_FMT, val);
421 	regmap_write(ctx->regmap, REG_LVDS_VCOM, 0x05);
422 	regmap_write(ctx->regmap, REG_LVDS_LANE,
423 		     (ctx->lvds_dual_link_even_odd_swap ?
424 		      REG_LVDS_LANE_EVEN_ODD_SWAP : 0) |
425 		     REG_LVDS_LANE_CHA_LVDS_TERM |
426 		     REG_LVDS_LANE_CHB_LVDS_TERM);
427 	regmap_write(ctx->regmap, REG_LVDS_CM, 0x00);
428 
429 	val = cpu_to_le16(ctx->mode.hdisplay);
430 	regmap_bulk_write(ctx->regmap, REG_VID_CHA_ACTIVE_LINE_LENGTH_LOW,
431 			  &val, 2);
432 	val = cpu_to_le16(ctx->mode.vdisplay);
433 	regmap_bulk_write(ctx->regmap, REG_VID_CHA_VERTICAL_DISPLAY_SIZE_LOW,
434 			  &val, 2);
435 	/* 32 + 1 pixel clock to ensure proper operation */
436 	val = cpu_to_le16(32 + 1);
437 	regmap_bulk_write(ctx->regmap, REG_VID_CHA_SYNC_DELAY_LOW, &val, 2);
438 	val = cpu_to_le16(ctx->mode.hsync_end - ctx->mode.hsync_start);
439 	regmap_bulk_write(ctx->regmap, REG_VID_CHA_HSYNC_PULSE_WIDTH_LOW,
440 			  &val, 2);
441 	val = cpu_to_le16(ctx->mode.vsync_end - ctx->mode.vsync_start);
442 	regmap_bulk_write(ctx->regmap, REG_VID_CHA_VSYNC_PULSE_WIDTH_LOW,
443 			  &val, 2);
444 	regmap_write(ctx->regmap, REG_VID_CHA_HORIZONTAL_BACK_PORCH,
445 		     ctx->mode.htotal - ctx->mode.hsync_end);
446 	regmap_write(ctx->regmap, REG_VID_CHA_VERTICAL_BACK_PORCH,
447 		     ctx->mode.vtotal - ctx->mode.vsync_end);
448 	regmap_write(ctx->regmap, REG_VID_CHA_HORIZONTAL_FRONT_PORCH,
449 		     ctx->mode.hsync_start - ctx->mode.hdisplay);
450 	regmap_write(ctx->regmap, REG_VID_CHA_VERTICAL_FRONT_PORCH,
451 		     ctx->mode.vsync_start - ctx->mode.vdisplay);
452 	regmap_write(ctx->regmap, REG_VID_CHA_TEST_PATTERN, 0x00);
453 
454 	/* Enable PLL */
455 	regmap_write(ctx->regmap, REG_RC_PLL_EN, REG_RC_PLL_EN_PLL_EN);
456 	usleep_range(3000, 4000);
457 	ret = regmap_read_poll_timeout(ctx->regmap, REG_RC_LVDS_PLL, pval,
458 				       pval & REG_RC_LVDS_PLL_PLL_EN_STAT,
459 				       1000, 100000);
460 	if (ret) {
461 		dev_err(ctx->dev, "failed to lock PLL, ret=%i\n", ret);
462 		/* On failure, disable PLL again and exit. */
463 		regmap_write(ctx->regmap, REG_RC_PLL_EN, 0x00);
464 		return;
465 	}
466 
467 	/* Trigger reset after CSR register update. */
468 	regmap_write(ctx->regmap, REG_RC_RESET, REG_RC_RESET_SOFT_RESET);
469 
470 	/* Clear all errors that got asserted during initialization. */
471 	regmap_read(ctx->regmap, REG_IRQ_STAT, &pval);
472 	regmap_write(ctx->regmap, REG_IRQ_STAT, pval);
473 }
474 
475 static void sn65dsi83_disable(struct drm_bridge *bridge)
476 {
477 	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
478 
479 	/* Clear reset, disable PLL */
480 	regmap_write(ctx->regmap, REG_RC_RESET, 0x00);
481 	regmap_write(ctx->regmap, REG_RC_PLL_EN, 0x00);
482 }
483 
484 static void sn65dsi83_post_disable(struct drm_bridge *bridge)
485 {
486 	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
487 
488 	/* Put the chip in reset, pull EN line low. */
489 	gpiod_set_value(ctx->enable_gpio, 0);
490 }
491 
492 static enum drm_mode_status
493 sn65dsi83_mode_valid(struct drm_bridge *bridge,
494 		     const struct drm_display_info *info,
495 		     const struct drm_display_mode *mode)
496 {
497 	/* LVDS output clock range 25..154 MHz */
498 	if (mode->clock < 25000)
499 		return MODE_CLOCK_LOW;
500 	if (mode->clock > 154000)
501 		return MODE_CLOCK_HIGH;
502 
503 	return MODE_OK;
504 }
505 
506 static void sn65dsi83_mode_set(struct drm_bridge *bridge,
507 			       const struct drm_display_mode *mode,
508 			       const struct drm_display_mode *adj)
509 {
510 	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
511 
512 	ctx->mode = *adj;
513 }
514 
515 static bool sn65dsi83_mode_fixup(struct drm_bridge *bridge,
516 				 const struct drm_display_mode *mode,
517 				 struct drm_display_mode *adj)
518 {
519 	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
520 	u32 input_bus_format = MEDIA_BUS_FMT_RGB888_1X24;
521 	struct drm_encoder *encoder = bridge->encoder;
522 	struct drm_device *ddev = encoder->dev;
523 	struct drm_connector *connector;
524 
525 	/* The DSI format is always RGB888_1X24 */
526 	list_for_each_entry(connector, &ddev->mode_config.connector_list, head) {
527 		switch (connector->display_info.bus_formats[0]) {
528 		case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
529 			ctx->lvds_format_24bpp = false;
530 			ctx->lvds_format_jeida = true;
531 			break;
532 		case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
533 			ctx->lvds_format_24bpp = true;
534 			ctx->lvds_format_jeida = true;
535 			break;
536 		case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
537 			ctx->lvds_format_24bpp = true;
538 			ctx->lvds_format_jeida = false;
539 			break;
540 		default:
541 			/*
542 			 * Some bridges still don't set the correct
543 			 * LVDS bus pixel format, use SPWG24 default
544 			 * format until those are fixed.
545 			 */
546 			ctx->lvds_format_24bpp = true;
547 			ctx->lvds_format_jeida = false;
548 			dev_warn(ctx->dev,
549 				 "Unsupported LVDS bus format 0x%04x, please check output bridge driver. Falling back to SPWG24.\n",
550 				 connector->display_info.bus_formats[0]);
551 			break;
552 		}
553 
554 		drm_display_info_set_bus_formats(&connector->display_info,
555 						 &input_bus_format, 1);
556 	}
557 
558 	return true;
559 }
560 
561 static const struct drm_bridge_funcs sn65dsi83_funcs = {
562 	.attach		= sn65dsi83_attach,
563 	.pre_enable	= sn65dsi83_pre_enable,
564 	.enable		= sn65dsi83_enable,
565 	.disable	= sn65dsi83_disable,
566 	.post_disable	= sn65dsi83_post_disable,
567 	.mode_valid	= sn65dsi83_mode_valid,
568 	.mode_set	= sn65dsi83_mode_set,
569 	.mode_fixup	= sn65dsi83_mode_fixup,
570 };
571 
572 static int sn65dsi83_parse_dt(struct sn65dsi83 *ctx, enum sn65dsi83_model model)
573 {
574 	struct drm_bridge *panel_bridge;
575 	struct device *dev = ctx->dev;
576 	struct device_node *endpoint;
577 	struct drm_panel *panel;
578 	int ret;
579 
580 	endpoint = of_graph_get_endpoint_by_regs(dev->of_node, 0, 0);
581 	ctx->dsi_lanes = of_property_count_u32_elems(endpoint, "data-lanes");
582 	ctx->host_node = of_graph_get_remote_port_parent(endpoint);
583 	of_node_put(endpoint);
584 
585 	if (ctx->dsi_lanes < 0 || ctx->dsi_lanes > 4)
586 		return -EINVAL;
587 	if (!ctx->host_node)
588 		return -ENODEV;
589 
590 	ctx->lvds_dual_link = false;
591 	ctx->lvds_dual_link_even_odd_swap = false;
592 	if (model != MODEL_SN65DSI83) {
593 		struct device_node *port2, *port3;
594 		int dual_link;
595 
596 		port2 = of_graph_get_port_by_id(dev->of_node, 2);
597 		port3 = of_graph_get_port_by_id(dev->of_node, 3);
598 		dual_link = drm_of_lvds_get_dual_link_pixel_order(port2, port3);
599 		of_node_put(port2);
600 		of_node_put(port3);
601 
602 		if (dual_link == DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS) {
603 			ctx->lvds_dual_link = true;
604 			/* Odd pixels to LVDS Channel A, even pixels to B */
605 			ctx->lvds_dual_link_even_odd_swap = false;
606 		} else if (dual_link == DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS) {
607 			ctx->lvds_dual_link = true;
608 			/* Even pixels to LVDS Channel A, odd pixels to B */
609 			ctx->lvds_dual_link_even_odd_swap = true;
610 		}
611 	}
612 
613 	ret = drm_of_find_panel_or_bridge(dev->of_node, 2, 0, &panel, &panel_bridge);
614 	if (ret < 0)
615 		return ret;
616 	if (panel) {
617 		panel_bridge = devm_drm_panel_bridge_add(dev, panel);
618 		if (IS_ERR(panel_bridge))
619 			return PTR_ERR(panel_bridge);
620 	}
621 
622 	ctx->panel_bridge = panel_bridge;
623 
624 	return 0;
625 }
626 
627 static int sn65dsi83_probe(struct i2c_client *client,
628 			   const struct i2c_device_id *id)
629 {
630 	struct device *dev = &client->dev;
631 	enum sn65dsi83_model model;
632 	struct sn65dsi83 *ctx;
633 	int ret;
634 
635 	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
636 	if (!ctx)
637 		return -ENOMEM;
638 
639 	ctx->dev = dev;
640 
641 	if (dev->of_node) {
642 		model = (enum sn65dsi83_model)(uintptr_t)
643 			of_device_get_match_data(dev);
644 	} else {
645 		model = id->driver_data;
646 	}
647 
648 	ctx->enable_gpio = devm_gpiod_get(ctx->dev, "enable", GPIOD_OUT_LOW);
649 	if (IS_ERR(ctx->enable_gpio))
650 		return PTR_ERR(ctx->enable_gpio);
651 
652 	ret = sn65dsi83_parse_dt(ctx, model);
653 	if (ret)
654 		return ret;
655 
656 	ctx->regmap = devm_regmap_init_i2c(client, &sn65dsi83_regmap_config);
657 	if (IS_ERR(ctx->regmap))
658 		return PTR_ERR(ctx->regmap);
659 
660 	dev_set_drvdata(dev, ctx);
661 	i2c_set_clientdata(client, ctx);
662 
663 	ctx->bridge.funcs = &sn65dsi83_funcs;
664 	ctx->bridge.of_node = dev->of_node;
665 	drm_bridge_add(&ctx->bridge);
666 
667 	return 0;
668 }
669 
670 static int sn65dsi83_remove(struct i2c_client *client)
671 {
672 	struct sn65dsi83 *ctx = i2c_get_clientdata(client);
673 
674 	mipi_dsi_detach(ctx->dsi);
675 	mipi_dsi_device_unregister(ctx->dsi);
676 	drm_bridge_remove(&ctx->bridge);
677 	of_node_put(ctx->host_node);
678 
679 	return 0;
680 }
681 
682 static struct i2c_device_id sn65dsi83_id[] = {
683 	{ "ti,sn65dsi83", MODEL_SN65DSI83 },
684 	{ "ti,sn65dsi84", MODEL_SN65DSI84 },
685 	{},
686 };
687 MODULE_DEVICE_TABLE(i2c, sn65dsi83_id);
688 
689 static const struct of_device_id sn65dsi83_match_table[] = {
690 	{ .compatible = "ti,sn65dsi83", .data = (void *)MODEL_SN65DSI83 },
691 	{ .compatible = "ti,sn65dsi84", .data = (void *)MODEL_SN65DSI84 },
692 	{},
693 };
694 MODULE_DEVICE_TABLE(of, sn65dsi83_match_table);
695 
696 static struct i2c_driver sn65dsi83_driver = {
697 	.probe = sn65dsi83_probe,
698 	.remove = sn65dsi83_remove,
699 	.id_table = sn65dsi83_id,
700 	.driver = {
701 		.name = "sn65dsi83",
702 		.of_match_table = sn65dsi83_match_table,
703 	},
704 };
705 module_i2c_driver(sn65dsi83_driver);
706 
707 MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
708 MODULE_DESCRIPTION("TI SN65DSI83 DSI to LVDS bridge driver");
709 MODULE_LICENSE("GPL v2");
710