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/media-bus-format.h>
33 #include <linux/module.h>
34 #include <linux/of.h>
35 #include <linux/of_graph.h>
36 #include <linux/regmap.h>
37 #include <linux/regulator/consumer.h>
38 
39 #include <drm/drm_atomic_helper.h>
40 #include <drm/drm_bridge.h>
41 #include <drm/drm_mipi_dsi.h>
42 #include <drm/drm_of.h>
43 #include <drm/drm_panel.h>
44 #include <drm/drm_print.h>
45 #include <drm/drm_probe_helper.h>
46 
47 /* ID registers */
48 #define REG_ID(n)				(0x00 + (n))
49 /* Reset and clock registers */
50 #define REG_RC_RESET				0x09
51 #define  REG_RC_RESET_SOFT_RESET		BIT(0)
52 #define REG_RC_LVDS_PLL				0x0a
53 #define  REG_RC_LVDS_PLL_PLL_EN_STAT		BIT(7)
54 #define  REG_RC_LVDS_PLL_LVDS_CLK_RANGE(n)	(((n) & 0x7) << 1)
55 #define  REG_RC_LVDS_PLL_HS_CLK_SRC_DPHY	BIT(0)
56 #define REG_RC_DSI_CLK				0x0b
57 #define  REG_RC_DSI_CLK_DSI_CLK_DIVIDER(n)	(((n) & 0x1f) << 3)
58 #define  REG_RC_DSI_CLK_REFCLK_MULTIPLIER(n)	((n) & 0x3)
59 #define REG_RC_PLL_EN				0x0d
60 #define  REG_RC_PLL_EN_PLL_EN			BIT(0)
61 /* DSI registers */
62 #define REG_DSI_LANE				0x10
63 #define  REG_DSI_LANE_LEFT_RIGHT_PIXELS		BIT(7)	/* DSI85-only */
64 #define  REG_DSI_LANE_DSI_CHANNEL_MODE_DUAL	0	/* DSI85-only */
65 #define  REG_DSI_LANE_DSI_CHANNEL_MODE_2SINGLE	BIT(6)	/* DSI85-only */
66 #define  REG_DSI_LANE_DSI_CHANNEL_MODE_SINGLE	BIT(5)
67 #define  REG_DSI_LANE_CHA_DSI_LANES(n)		(((n) & 0x3) << 3)
68 #define  REG_DSI_LANE_CHB_DSI_LANES(n)		(((n) & 0x3) << 1)
69 #define  REG_DSI_LANE_SOT_ERR_TOL_DIS		BIT(0)
70 #define REG_DSI_EQ				0x11
71 #define  REG_DSI_EQ_CHA_DSI_DATA_EQ(n)		(((n) & 0x3) << 6)
72 #define  REG_DSI_EQ_CHA_DSI_CLK_EQ(n)		(((n) & 0x3) << 2)
73 #define REG_DSI_CLK				0x12
74 #define  REG_DSI_CLK_CHA_DSI_CLK_RANGE(n)	((n) & 0xff)
75 /* LVDS registers */
76 #define REG_LVDS_FMT				0x18
77 #define  REG_LVDS_FMT_DE_NEG_POLARITY		BIT(7)
78 #define  REG_LVDS_FMT_HS_NEG_POLARITY		BIT(6)
79 #define  REG_LVDS_FMT_VS_NEG_POLARITY		BIT(5)
80 #define  REG_LVDS_FMT_LVDS_LINK_CFG		BIT(4)	/* 0:AB 1:A-only */
81 #define  REG_LVDS_FMT_CHA_24BPP_MODE		BIT(3)
82 #define  REG_LVDS_FMT_CHB_24BPP_MODE		BIT(2)
83 #define  REG_LVDS_FMT_CHA_24BPP_FORMAT1		BIT(1)
84 #define  REG_LVDS_FMT_CHB_24BPP_FORMAT1		BIT(0)
85 #define REG_LVDS_VCOM				0x19
86 #define  REG_LVDS_VCOM_CHA_LVDS_VOCM		BIT(6)
87 #define  REG_LVDS_VCOM_CHB_LVDS_VOCM		BIT(4)
88 #define  REG_LVDS_VCOM_CHA_LVDS_VOD_SWING(n)	(((n) & 0x3) << 2)
89 #define  REG_LVDS_VCOM_CHB_LVDS_VOD_SWING(n)	((n) & 0x3)
90 #define REG_LVDS_LANE				0x1a
91 #define  REG_LVDS_LANE_EVEN_ODD_SWAP		BIT(6)
92 #define  REG_LVDS_LANE_CHA_REVERSE_LVDS		BIT(5)
93 #define  REG_LVDS_LANE_CHB_REVERSE_LVDS		BIT(4)
94 #define  REG_LVDS_LANE_CHA_LVDS_TERM		BIT(1)
95 #define  REG_LVDS_LANE_CHB_LVDS_TERM		BIT(0)
96 #define REG_LVDS_CM				0x1b
97 #define  REG_LVDS_CM_CHA_LVDS_CM_ADJUST(n)	(((n) & 0x3) << 4)
98 #define  REG_LVDS_CM_CHB_LVDS_CM_ADJUST(n)	((n) & 0x3)
99 /* Video registers */
100 #define REG_VID_CHA_ACTIVE_LINE_LENGTH_LOW	0x20
101 #define REG_VID_CHA_ACTIVE_LINE_LENGTH_HIGH	0x21
102 #define REG_VID_CHA_VERTICAL_DISPLAY_SIZE_LOW	0x24
103 #define REG_VID_CHA_VERTICAL_DISPLAY_SIZE_HIGH	0x25
104 #define REG_VID_CHA_SYNC_DELAY_LOW		0x28
105 #define REG_VID_CHA_SYNC_DELAY_HIGH		0x29
106 #define REG_VID_CHA_HSYNC_PULSE_WIDTH_LOW	0x2c
107 #define REG_VID_CHA_HSYNC_PULSE_WIDTH_HIGH	0x2d
108 #define REG_VID_CHA_VSYNC_PULSE_WIDTH_LOW	0x30
109 #define REG_VID_CHA_VSYNC_PULSE_WIDTH_HIGH	0x31
110 #define REG_VID_CHA_HORIZONTAL_BACK_PORCH	0x34
111 #define REG_VID_CHA_VERTICAL_BACK_PORCH		0x36
112 #define REG_VID_CHA_HORIZONTAL_FRONT_PORCH	0x38
113 #define REG_VID_CHA_VERTICAL_FRONT_PORCH	0x3a
114 #define REG_VID_CHA_TEST_PATTERN		0x3c
115 /* IRQ registers */
116 #define REG_IRQ_GLOBAL				0xe0
117 #define  REG_IRQ_GLOBAL_IRQ_EN			BIT(0)
118 #define REG_IRQ_EN				0xe1
119 #define  REG_IRQ_EN_CHA_SYNCH_ERR_EN		BIT(7)
120 #define  REG_IRQ_EN_CHA_CRC_ERR_EN		BIT(6)
121 #define  REG_IRQ_EN_CHA_UNC_ECC_ERR_EN		BIT(5)
122 #define  REG_IRQ_EN_CHA_COR_ECC_ERR_EN		BIT(4)
123 #define  REG_IRQ_EN_CHA_LLP_ERR_EN		BIT(3)
124 #define  REG_IRQ_EN_CHA_SOT_BIT_ERR_EN		BIT(2)
125 #define  REG_IRQ_EN_CHA_PLL_UNLOCK_EN		BIT(0)
126 #define REG_IRQ_STAT				0xe5
127 #define  REG_IRQ_STAT_CHA_SYNCH_ERR		BIT(7)
128 #define  REG_IRQ_STAT_CHA_CRC_ERR		BIT(6)
129 #define  REG_IRQ_STAT_CHA_UNC_ECC_ERR		BIT(5)
130 #define  REG_IRQ_STAT_CHA_COR_ECC_ERR		BIT(4)
131 #define  REG_IRQ_STAT_CHA_LLP_ERR		BIT(3)
132 #define  REG_IRQ_STAT_CHA_SOT_BIT_ERR		BIT(2)
133 #define  REG_IRQ_STAT_CHA_PLL_UNLOCK		BIT(0)
134 
135 enum sn65dsi83_model {
136 	MODEL_SN65DSI83,
137 	MODEL_SN65DSI84,
138 };
139 
140 struct sn65dsi83 {
141 	struct drm_bridge		bridge;
142 	struct device			*dev;
143 	struct regmap			*regmap;
144 	struct mipi_dsi_device		*dsi;
145 	struct drm_bridge		*panel_bridge;
146 	struct gpio_desc		*enable_gpio;
147 	struct regulator		*vcc;
148 	bool				lvds_dual_link;
149 	bool				lvds_dual_link_even_odd_swap;
150 };
151 
152 static const struct regmap_range sn65dsi83_readable_ranges[] = {
153 	regmap_reg_range(REG_ID(0), REG_ID(8)),
154 	regmap_reg_range(REG_RC_LVDS_PLL, REG_RC_DSI_CLK),
155 	regmap_reg_range(REG_RC_PLL_EN, REG_RC_PLL_EN),
156 	regmap_reg_range(REG_DSI_LANE, REG_DSI_CLK),
157 	regmap_reg_range(REG_LVDS_FMT, REG_LVDS_CM),
158 	regmap_reg_range(REG_VID_CHA_ACTIVE_LINE_LENGTH_LOW,
159 			 REG_VID_CHA_ACTIVE_LINE_LENGTH_HIGH),
160 	regmap_reg_range(REG_VID_CHA_VERTICAL_DISPLAY_SIZE_LOW,
161 			 REG_VID_CHA_VERTICAL_DISPLAY_SIZE_HIGH),
162 	regmap_reg_range(REG_VID_CHA_SYNC_DELAY_LOW,
163 			 REG_VID_CHA_SYNC_DELAY_HIGH),
164 	regmap_reg_range(REG_VID_CHA_HSYNC_PULSE_WIDTH_LOW,
165 			 REG_VID_CHA_HSYNC_PULSE_WIDTH_HIGH),
166 	regmap_reg_range(REG_VID_CHA_VSYNC_PULSE_WIDTH_LOW,
167 			 REG_VID_CHA_VSYNC_PULSE_WIDTH_HIGH),
168 	regmap_reg_range(REG_VID_CHA_HORIZONTAL_BACK_PORCH,
169 			 REG_VID_CHA_HORIZONTAL_BACK_PORCH),
170 	regmap_reg_range(REG_VID_CHA_VERTICAL_BACK_PORCH,
171 			 REG_VID_CHA_VERTICAL_BACK_PORCH),
172 	regmap_reg_range(REG_VID_CHA_HORIZONTAL_FRONT_PORCH,
173 			 REG_VID_CHA_HORIZONTAL_FRONT_PORCH),
174 	regmap_reg_range(REG_VID_CHA_VERTICAL_FRONT_PORCH,
175 			 REG_VID_CHA_VERTICAL_FRONT_PORCH),
176 	regmap_reg_range(REG_VID_CHA_TEST_PATTERN, REG_VID_CHA_TEST_PATTERN),
177 	regmap_reg_range(REG_IRQ_GLOBAL, REG_IRQ_EN),
178 	regmap_reg_range(REG_IRQ_STAT, REG_IRQ_STAT),
179 };
180 
181 static const struct regmap_access_table sn65dsi83_readable_table = {
182 	.yes_ranges = sn65dsi83_readable_ranges,
183 	.n_yes_ranges = ARRAY_SIZE(sn65dsi83_readable_ranges),
184 };
185 
186 static const struct regmap_range sn65dsi83_writeable_ranges[] = {
187 	regmap_reg_range(REG_RC_RESET, REG_RC_DSI_CLK),
188 	regmap_reg_range(REG_RC_PLL_EN, REG_RC_PLL_EN),
189 	regmap_reg_range(REG_DSI_LANE, REG_DSI_CLK),
190 	regmap_reg_range(REG_LVDS_FMT, REG_LVDS_CM),
191 	regmap_reg_range(REG_VID_CHA_ACTIVE_LINE_LENGTH_LOW,
192 			 REG_VID_CHA_ACTIVE_LINE_LENGTH_HIGH),
193 	regmap_reg_range(REG_VID_CHA_VERTICAL_DISPLAY_SIZE_LOW,
194 			 REG_VID_CHA_VERTICAL_DISPLAY_SIZE_HIGH),
195 	regmap_reg_range(REG_VID_CHA_SYNC_DELAY_LOW,
196 			 REG_VID_CHA_SYNC_DELAY_HIGH),
197 	regmap_reg_range(REG_VID_CHA_HSYNC_PULSE_WIDTH_LOW,
198 			 REG_VID_CHA_HSYNC_PULSE_WIDTH_HIGH),
199 	regmap_reg_range(REG_VID_CHA_VSYNC_PULSE_WIDTH_LOW,
200 			 REG_VID_CHA_VSYNC_PULSE_WIDTH_HIGH),
201 	regmap_reg_range(REG_VID_CHA_HORIZONTAL_BACK_PORCH,
202 			 REG_VID_CHA_HORIZONTAL_BACK_PORCH),
203 	regmap_reg_range(REG_VID_CHA_VERTICAL_BACK_PORCH,
204 			 REG_VID_CHA_VERTICAL_BACK_PORCH),
205 	regmap_reg_range(REG_VID_CHA_HORIZONTAL_FRONT_PORCH,
206 			 REG_VID_CHA_HORIZONTAL_FRONT_PORCH),
207 	regmap_reg_range(REG_VID_CHA_VERTICAL_FRONT_PORCH,
208 			 REG_VID_CHA_VERTICAL_FRONT_PORCH),
209 	regmap_reg_range(REG_VID_CHA_TEST_PATTERN, REG_VID_CHA_TEST_PATTERN),
210 	regmap_reg_range(REG_IRQ_GLOBAL, REG_IRQ_EN),
211 	regmap_reg_range(REG_IRQ_STAT, REG_IRQ_STAT),
212 };
213 
214 static const struct regmap_access_table sn65dsi83_writeable_table = {
215 	.yes_ranges = sn65dsi83_writeable_ranges,
216 	.n_yes_ranges = ARRAY_SIZE(sn65dsi83_writeable_ranges),
217 };
218 
219 static const struct regmap_range sn65dsi83_volatile_ranges[] = {
220 	regmap_reg_range(REG_RC_RESET, REG_RC_RESET),
221 	regmap_reg_range(REG_RC_LVDS_PLL, REG_RC_LVDS_PLL),
222 	regmap_reg_range(REG_IRQ_STAT, REG_IRQ_STAT),
223 };
224 
225 static const struct regmap_access_table sn65dsi83_volatile_table = {
226 	.yes_ranges = sn65dsi83_volatile_ranges,
227 	.n_yes_ranges = ARRAY_SIZE(sn65dsi83_volatile_ranges),
228 };
229 
230 static const struct regmap_config sn65dsi83_regmap_config = {
231 	.reg_bits = 8,
232 	.val_bits = 8,
233 	.rd_table = &sn65dsi83_readable_table,
234 	.wr_table = &sn65dsi83_writeable_table,
235 	.volatile_table = &sn65dsi83_volatile_table,
236 	.cache_type = REGCACHE_RBTREE,
237 	.max_register = REG_IRQ_STAT,
238 };
239 
bridge_to_sn65dsi83(struct drm_bridge * bridge)240 static struct sn65dsi83 *bridge_to_sn65dsi83(struct drm_bridge *bridge)
241 {
242 	return container_of(bridge, struct sn65dsi83, bridge);
243 }
244 
sn65dsi83_attach(struct drm_bridge * bridge,enum drm_bridge_attach_flags flags)245 static int sn65dsi83_attach(struct drm_bridge *bridge,
246 			    enum drm_bridge_attach_flags flags)
247 {
248 	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
249 
250 	return drm_bridge_attach(bridge->encoder, ctx->panel_bridge,
251 				 &ctx->bridge, flags);
252 }
253 
sn65dsi83_detach(struct drm_bridge * bridge)254 static void sn65dsi83_detach(struct drm_bridge *bridge)
255 {
256 	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
257 
258 	if (!ctx->dsi)
259 		return;
260 
261 	ctx->dsi = NULL;
262 }
263 
sn65dsi83_get_lvds_range(struct sn65dsi83 * ctx,const struct drm_display_mode * mode)264 static u8 sn65dsi83_get_lvds_range(struct sn65dsi83 *ctx,
265 				   const struct drm_display_mode *mode)
266 {
267 	/*
268 	 * The encoding of the LVDS_CLK_RANGE is as follows:
269 	 * 000 - 25 MHz <= LVDS_CLK < 37.5 MHz
270 	 * 001 - 37.5 MHz <= LVDS_CLK < 62.5 MHz
271 	 * 010 - 62.5 MHz <= LVDS_CLK < 87.5 MHz
272 	 * 011 - 87.5 MHz <= LVDS_CLK < 112.5 MHz
273 	 * 100 - 112.5 MHz <= LVDS_CLK < 137.5 MHz
274 	 * 101 - 137.5 MHz <= LVDS_CLK <= 154 MHz
275 	 * which is a range of 12.5MHz..162.5MHz in 50MHz steps, except that
276 	 * the ends of the ranges are clamped to the supported range. Since
277 	 * sn65dsi83_mode_valid() already filters the valid modes and limits
278 	 * the clock to 25..154 MHz, the range calculation can be simplified
279 	 * as follows:
280 	 */
281 	int mode_clock = mode->clock;
282 
283 	if (ctx->lvds_dual_link)
284 		mode_clock /= 2;
285 
286 	return (mode_clock - 12500) / 25000;
287 }
288 
sn65dsi83_get_dsi_range(struct sn65dsi83 * ctx,const struct drm_display_mode * mode)289 static u8 sn65dsi83_get_dsi_range(struct sn65dsi83 *ctx,
290 				  const struct drm_display_mode *mode)
291 {
292 	/*
293 	 * The encoding of the CHA_DSI_CLK_RANGE is as follows:
294 	 * 0x00 through 0x07 - Reserved
295 	 * 0x08 - 40 <= DSI_CLK < 45 MHz
296 	 * 0x09 - 45 <= DSI_CLK < 50 MHz
297 	 * ...
298 	 * 0x63 - 495 <= DSI_CLK < 500 MHz
299 	 * 0x64 - 500 MHz
300 	 * 0x65 through 0xFF - Reserved
301 	 * which is DSI clock in 5 MHz steps, clamped to 40..500 MHz.
302 	 * The DSI clock are calculated as:
303 	 *  DSI_CLK = mode clock * bpp / dsi_data_lanes / 2
304 	 * the 2 is there because the bus is DDR.
305 	 */
306 	return DIV_ROUND_UP(clamp((unsigned int)mode->clock *
307 			    mipi_dsi_pixel_format_to_bpp(ctx->dsi->format) /
308 			    ctx->dsi->lanes / 2, 40000U, 500000U), 5000U);
309 }
310 
sn65dsi83_get_dsi_div(struct sn65dsi83 * ctx)311 static u8 sn65dsi83_get_dsi_div(struct sn65dsi83 *ctx)
312 {
313 	/* The divider is (DSI_CLK / LVDS_CLK) - 1, which really is: */
314 	unsigned int dsi_div = mipi_dsi_pixel_format_to_bpp(ctx->dsi->format);
315 
316 	dsi_div /= ctx->dsi->lanes;
317 
318 	if (!ctx->lvds_dual_link)
319 		dsi_div /= 2;
320 
321 	return dsi_div - 1;
322 }
323 
sn65dsi83_atomic_pre_enable(struct drm_bridge * bridge,struct drm_bridge_state * old_bridge_state)324 static void sn65dsi83_atomic_pre_enable(struct drm_bridge *bridge,
325 					struct drm_bridge_state *old_bridge_state)
326 {
327 	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
328 	struct drm_atomic_state *state = old_bridge_state->base.state;
329 	const struct drm_bridge_state *bridge_state;
330 	const struct drm_crtc_state *crtc_state;
331 	const struct drm_display_mode *mode;
332 	struct drm_connector *connector;
333 	struct drm_crtc *crtc;
334 	bool lvds_format_24bpp;
335 	bool lvds_format_jeida;
336 	unsigned int pval;
337 	__le16 le16val;
338 	u16 val;
339 	int ret;
340 
341 	ret = regulator_enable(ctx->vcc);
342 	if (ret) {
343 		dev_err(ctx->dev, "Failed to enable vcc: %d\n", ret);
344 		return;
345 	}
346 
347 	/* Deassert reset */
348 	gpiod_set_value_cansleep(ctx->enable_gpio, 1);
349 	usleep_range(10000, 11000);
350 
351 	/* Get the LVDS format from the bridge state. */
352 	bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
353 
354 	switch (bridge_state->output_bus_cfg.format) {
355 	case MEDIA_BUS_FMT_RGB666_1X7X3_SPWG:
356 		lvds_format_24bpp = false;
357 		lvds_format_jeida = true;
358 		break;
359 	case MEDIA_BUS_FMT_RGB888_1X7X4_JEIDA:
360 		lvds_format_24bpp = true;
361 		lvds_format_jeida = true;
362 		break;
363 	case MEDIA_BUS_FMT_RGB888_1X7X4_SPWG:
364 		lvds_format_24bpp = true;
365 		lvds_format_jeida = false;
366 		break;
367 	default:
368 		/*
369 		 * Some bridges still don't set the correct
370 		 * LVDS bus pixel format, use SPWG24 default
371 		 * format until those are fixed.
372 		 */
373 		lvds_format_24bpp = true;
374 		lvds_format_jeida = false;
375 		dev_warn(ctx->dev,
376 			 "Unsupported LVDS bus format 0x%04x, please check output bridge driver. Falling back to SPWG24.\n",
377 			 bridge_state->output_bus_cfg.format);
378 		break;
379 	}
380 
381 	/*
382 	 * Retrieve the CRTC adjusted mode. This requires a little dance to go
383 	 * from the bridge to the encoder, to the connector and to the CRTC.
384 	 */
385 	connector = drm_atomic_get_new_connector_for_encoder(state,
386 							     bridge->encoder);
387 	crtc = drm_atomic_get_new_connector_state(state, connector)->crtc;
388 	crtc_state = drm_atomic_get_new_crtc_state(state, crtc);
389 	mode = &crtc_state->adjusted_mode;
390 
391 	/* Clear reset, disable PLL */
392 	regmap_write(ctx->regmap, REG_RC_RESET, 0x00);
393 	regmap_write(ctx->regmap, REG_RC_PLL_EN, 0x00);
394 
395 	/* Reference clock derived from DSI link clock. */
396 	regmap_write(ctx->regmap, REG_RC_LVDS_PLL,
397 		     REG_RC_LVDS_PLL_LVDS_CLK_RANGE(sn65dsi83_get_lvds_range(ctx, mode)) |
398 		     REG_RC_LVDS_PLL_HS_CLK_SRC_DPHY);
399 	regmap_write(ctx->regmap, REG_DSI_CLK,
400 		     REG_DSI_CLK_CHA_DSI_CLK_RANGE(sn65dsi83_get_dsi_range(ctx, mode)));
401 	regmap_write(ctx->regmap, REG_RC_DSI_CLK,
402 		     REG_RC_DSI_CLK_DSI_CLK_DIVIDER(sn65dsi83_get_dsi_div(ctx)));
403 
404 	/* Set number of DSI lanes and LVDS link config. */
405 	regmap_write(ctx->regmap, REG_DSI_LANE,
406 		     REG_DSI_LANE_DSI_CHANNEL_MODE_SINGLE |
407 		     REG_DSI_LANE_CHA_DSI_LANES(~(ctx->dsi->lanes - 1)) |
408 		     /* CHB is DSI85-only, set to default on DSI83/DSI84 */
409 		     REG_DSI_LANE_CHB_DSI_LANES(3));
410 	/* No equalization. */
411 	regmap_write(ctx->regmap, REG_DSI_EQ, 0x00);
412 
413 	/* Set up sync signal polarity. */
414 	val = (mode->flags & DRM_MODE_FLAG_NHSYNC ?
415 	       REG_LVDS_FMT_HS_NEG_POLARITY : 0) |
416 	      (mode->flags & DRM_MODE_FLAG_NVSYNC ?
417 	       REG_LVDS_FMT_VS_NEG_POLARITY : 0);
418 
419 	/* Set up bits-per-pixel, 18bpp or 24bpp. */
420 	if (lvds_format_24bpp) {
421 		val |= REG_LVDS_FMT_CHA_24BPP_MODE;
422 		if (ctx->lvds_dual_link)
423 			val |= REG_LVDS_FMT_CHB_24BPP_MODE;
424 	}
425 
426 	/* Set up LVDS format, JEIDA/Format 1 or SPWG/Format 2 */
427 	if (lvds_format_jeida) {
428 		val |= REG_LVDS_FMT_CHA_24BPP_FORMAT1;
429 		if (ctx->lvds_dual_link)
430 			val |= REG_LVDS_FMT_CHB_24BPP_FORMAT1;
431 	}
432 
433 	/* Set up LVDS output config (DSI84,DSI85) */
434 	if (!ctx->lvds_dual_link)
435 		val |= REG_LVDS_FMT_LVDS_LINK_CFG;
436 
437 	regmap_write(ctx->regmap, REG_LVDS_FMT, val);
438 	regmap_write(ctx->regmap, REG_LVDS_VCOM, 0x05);
439 	regmap_write(ctx->regmap, REG_LVDS_LANE,
440 		     (ctx->lvds_dual_link_even_odd_swap ?
441 		      REG_LVDS_LANE_EVEN_ODD_SWAP : 0) |
442 		     REG_LVDS_LANE_CHA_LVDS_TERM |
443 		     REG_LVDS_LANE_CHB_LVDS_TERM);
444 	regmap_write(ctx->regmap, REG_LVDS_CM, 0x00);
445 
446 	le16val = cpu_to_le16(mode->hdisplay);
447 	regmap_bulk_write(ctx->regmap, REG_VID_CHA_ACTIVE_LINE_LENGTH_LOW,
448 			  &le16val, 2);
449 	le16val = cpu_to_le16(mode->vdisplay);
450 	regmap_bulk_write(ctx->regmap, REG_VID_CHA_VERTICAL_DISPLAY_SIZE_LOW,
451 			  &le16val, 2);
452 	/* 32 + 1 pixel clock to ensure proper operation */
453 	le16val = cpu_to_le16(32 + 1);
454 	regmap_bulk_write(ctx->regmap, REG_VID_CHA_SYNC_DELAY_LOW, &le16val, 2);
455 	le16val = cpu_to_le16(mode->hsync_end - mode->hsync_start);
456 	regmap_bulk_write(ctx->regmap, REG_VID_CHA_HSYNC_PULSE_WIDTH_LOW,
457 			  &le16val, 2);
458 	le16val = cpu_to_le16(mode->vsync_end - mode->vsync_start);
459 	regmap_bulk_write(ctx->regmap, REG_VID_CHA_VSYNC_PULSE_WIDTH_LOW,
460 			  &le16val, 2);
461 	regmap_write(ctx->regmap, REG_VID_CHA_HORIZONTAL_BACK_PORCH,
462 		     mode->htotal - mode->hsync_end);
463 	regmap_write(ctx->regmap, REG_VID_CHA_VERTICAL_BACK_PORCH,
464 		     mode->vtotal - mode->vsync_end);
465 	regmap_write(ctx->regmap, REG_VID_CHA_HORIZONTAL_FRONT_PORCH,
466 		     mode->hsync_start - mode->hdisplay);
467 	regmap_write(ctx->regmap, REG_VID_CHA_VERTICAL_FRONT_PORCH,
468 		     mode->vsync_start - mode->vdisplay);
469 	regmap_write(ctx->regmap, REG_VID_CHA_TEST_PATTERN, 0x00);
470 
471 	/* Enable PLL */
472 	regmap_write(ctx->regmap, REG_RC_PLL_EN, REG_RC_PLL_EN_PLL_EN);
473 	usleep_range(3000, 4000);
474 	ret = regmap_read_poll_timeout(ctx->regmap, REG_RC_LVDS_PLL, pval,
475 				       pval & REG_RC_LVDS_PLL_PLL_EN_STAT,
476 				       1000, 100000);
477 	if (ret) {
478 		dev_err(ctx->dev, "failed to lock PLL, ret=%i\n", ret);
479 		/* On failure, disable PLL again and exit. */
480 		regmap_write(ctx->regmap, REG_RC_PLL_EN, 0x00);
481 		regulator_disable(ctx->vcc);
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 	/* Wait for 10ms after soft reset as specified in datasheet */
489 	usleep_range(10000, 12000);
490 }
491 
sn65dsi83_atomic_enable(struct drm_bridge * bridge,struct drm_bridge_state * old_bridge_state)492 static void sn65dsi83_atomic_enable(struct drm_bridge *bridge,
493 				    struct drm_bridge_state *old_bridge_state)
494 {
495 	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
496 	unsigned int pval;
497 
498 	/* Clear all errors that got asserted during initialization. */
499 	regmap_read(ctx->regmap, REG_IRQ_STAT, &pval);
500 	regmap_write(ctx->regmap, REG_IRQ_STAT, pval);
501 
502 	/* Wait for 1ms and check for errors in status register */
503 	usleep_range(1000, 1100);
504 	regmap_read(ctx->regmap, REG_IRQ_STAT, &pval);
505 	if (pval)
506 		dev_err(ctx->dev, "Unexpected link status 0x%02x\n", pval);
507 }
508 
sn65dsi83_atomic_disable(struct drm_bridge * bridge,struct drm_bridge_state * old_bridge_state)509 static void sn65dsi83_atomic_disable(struct drm_bridge *bridge,
510 				     struct drm_bridge_state *old_bridge_state)
511 {
512 	struct sn65dsi83 *ctx = bridge_to_sn65dsi83(bridge);
513 	int ret;
514 
515 	/* Put the chip in reset, pull EN line low, and assure 10ms reset low timing. */
516 	gpiod_set_value_cansleep(ctx->enable_gpio, 0);
517 	usleep_range(10000, 11000);
518 
519 	ret = regulator_disable(ctx->vcc);
520 	if (ret)
521 		dev_err(ctx->dev, "Failed to disable vcc: %d\n", ret);
522 
523 	regcache_mark_dirty(ctx->regmap);
524 }
525 
526 static enum drm_mode_status
sn65dsi83_mode_valid(struct drm_bridge * bridge,const struct drm_display_info * info,const struct drm_display_mode * mode)527 sn65dsi83_mode_valid(struct drm_bridge *bridge,
528 		     const struct drm_display_info *info,
529 		     const struct drm_display_mode *mode)
530 {
531 	/* LVDS output clock range 25..154 MHz */
532 	if (mode->clock < 25000)
533 		return MODE_CLOCK_LOW;
534 	if (mode->clock > 154000)
535 		return MODE_CLOCK_HIGH;
536 
537 	return MODE_OK;
538 }
539 
540 #define MAX_INPUT_SEL_FORMATS	1
541 
542 static u32 *
sn65dsi83_atomic_get_input_bus_fmts(struct drm_bridge * bridge,struct drm_bridge_state * bridge_state,struct drm_crtc_state * crtc_state,struct drm_connector_state * conn_state,u32 output_fmt,unsigned int * num_input_fmts)543 sn65dsi83_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
544 				    struct drm_bridge_state *bridge_state,
545 				    struct drm_crtc_state *crtc_state,
546 				    struct drm_connector_state *conn_state,
547 				    u32 output_fmt,
548 				    unsigned int *num_input_fmts)
549 {
550 	u32 *input_fmts;
551 
552 	*num_input_fmts = 0;
553 
554 	input_fmts = kcalloc(MAX_INPUT_SEL_FORMATS, sizeof(*input_fmts),
555 			     GFP_KERNEL);
556 	if (!input_fmts)
557 		return NULL;
558 
559 	/* This is the DSI-end bus format */
560 	input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X24;
561 	*num_input_fmts = 1;
562 
563 	return input_fmts;
564 }
565 
566 static const struct drm_bridge_funcs sn65dsi83_funcs = {
567 	.attach			= sn65dsi83_attach,
568 	.detach			= sn65dsi83_detach,
569 	.atomic_enable		= sn65dsi83_atomic_enable,
570 	.atomic_pre_enable	= sn65dsi83_atomic_pre_enable,
571 	.atomic_disable		= sn65dsi83_atomic_disable,
572 	.mode_valid		= sn65dsi83_mode_valid,
573 
574 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
575 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
576 	.atomic_reset = drm_atomic_helper_bridge_reset,
577 	.atomic_get_input_bus_fmts = sn65dsi83_atomic_get_input_bus_fmts,
578 };
579 
sn65dsi83_parse_dt(struct sn65dsi83 * ctx,enum sn65dsi83_model model)580 static int sn65dsi83_parse_dt(struct sn65dsi83 *ctx, enum sn65dsi83_model model)
581 {
582 	struct drm_bridge *panel_bridge;
583 	struct device *dev = ctx->dev;
584 
585 	ctx->lvds_dual_link = false;
586 	ctx->lvds_dual_link_even_odd_swap = false;
587 	if (model != MODEL_SN65DSI83) {
588 		struct device_node *port2, *port3;
589 		int dual_link;
590 
591 		port2 = of_graph_get_port_by_id(dev->of_node, 2);
592 		port3 = of_graph_get_port_by_id(dev->of_node, 3);
593 		dual_link = drm_of_lvds_get_dual_link_pixel_order(port2, port3);
594 		of_node_put(port2);
595 		of_node_put(port3);
596 
597 		if (dual_link == DRM_LVDS_DUAL_LINK_ODD_EVEN_PIXELS) {
598 			ctx->lvds_dual_link = true;
599 			/* Odd pixels to LVDS Channel A, even pixels to B */
600 			ctx->lvds_dual_link_even_odd_swap = false;
601 		} else if (dual_link == DRM_LVDS_DUAL_LINK_EVEN_ODD_PIXELS) {
602 			ctx->lvds_dual_link = true;
603 			/* Even pixels to LVDS Channel A, odd pixels to B */
604 			ctx->lvds_dual_link_even_odd_swap = true;
605 		}
606 	}
607 
608 	panel_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 2, 0);
609 	if (IS_ERR(panel_bridge))
610 		return PTR_ERR(panel_bridge);
611 
612 	ctx->panel_bridge = panel_bridge;
613 
614 	ctx->vcc = devm_regulator_get(dev, "vcc");
615 	if (IS_ERR(ctx->vcc))
616 		return dev_err_probe(dev, PTR_ERR(ctx->vcc),
617 				     "Failed to get supply 'vcc'\n");
618 
619 	return 0;
620 }
621 
sn65dsi83_host_attach(struct sn65dsi83 * ctx)622 static int sn65dsi83_host_attach(struct sn65dsi83 *ctx)
623 {
624 	struct device *dev = ctx->dev;
625 	struct device_node *host_node;
626 	struct device_node *endpoint;
627 	struct mipi_dsi_device *dsi;
628 	struct mipi_dsi_host *host;
629 	const struct mipi_dsi_device_info info = {
630 		.type = "sn65dsi83",
631 		.channel = 0,
632 		.node = NULL,
633 	};
634 	int dsi_lanes, ret;
635 
636 	endpoint = of_graph_get_endpoint_by_regs(dev->of_node, 0, -1);
637 	dsi_lanes = drm_of_get_data_lanes_count(endpoint, 1, 4);
638 	host_node = of_graph_get_remote_port_parent(endpoint);
639 	host = of_find_mipi_dsi_host_by_node(host_node);
640 	of_node_put(host_node);
641 	of_node_put(endpoint);
642 
643 	if (!host)
644 		return -EPROBE_DEFER;
645 
646 	if (dsi_lanes < 0)
647 		return dsi_lanes;
648 
649 	dsi = devm_mipi_dsi_device_register_full(dev, host, &info);
650 	if (IS_ERR(dsi))
651 		return dev_err_probe(dev, PTR_ERR(dsi),
652 				     "failed to create dsi device\n");
653 
654 	ctx->dsi = dsi;
655 
656 	dsi->lanes = dsi_lanes;
657 	dsi->format = MIPI_DSI_FMT_RGB888;
658 	dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
659 			  MIPI_DSI_MODE_VIDEO_NO_HFP | MIPI_DSI_MODE_VIDEO_NO_HBP |
660 			  MIPI_DSI_MODE_VIDEO_NO_HSA | MIPI_DSI_MODE_NO_EOT_PACKET;
661 
662 	ret = devm_mipi_dsi_attach(dev, dsi);
663 	if (ret < 0) {
664 		dev_err(dev, "failed to attach dsi to host: %d\n", ret);
665 		return ret;
666 	}
667 
668 	return 0;
669 }
670 
sn65dsi83_probe(struct i2c_client * client)671 static int sn65dsi83_probe(struct i2c_client *client)
672 {
673 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
674 	struct device *dev = &client->dev;
675 	enum sn65dsi83_model model;
676 	struct sn65dsi83 *ctx;
677 	int ret;
678 
679 	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
680 	if (!ctx)
681 		return -ENOMEM;
682 
683 	ctx->dev = dev;
684 
685 	if (dev->of_node) {
686 		model = (enum sn65dsi83_model)(uintptr_t)
687 			of_device_get_match_data(dev);
688 	} else {
689 		model = id->driver_data;
690 	}
691 
692 	/* Put the chip in reset, pull EN line low, and assure 10ms reset low timing. */
693 	ctx->enable_gpio = devm_gpiod_get_optional(ctx->dev, "enable",
694 						   GPIOD_OUT_LOW);
695 	if (IS_ERR(ctx->enable_gpio))
696 		return dev_err_probe(dev, PTR_ERR(ctx->enable_gpio), "failed to get enable GPIO\n");
697 
698 	usleep_range(10000, 11000);
699 
700 	ret = sn65dsi83_parse_dt(ctx, model);
701 	if (ret)
702 		return ret;
703 
704 	ctx->regmap = devm_regmap_init_i2c(client, &sn65dsi83_regmap_config);
705 	if (IS_ERR(ctx->regmap))
706 		return dev_err_probe(dev, PTR_ERR(ctx->regmap), "failed to get regmap\n");
707 
708 	dev_set_drvdata(dev, ctx);
709 	i2c_set_clientdata(client, ctx);
710 
711 	ctx->bridge.funcs = &sn65dsi83_funcs;
712 	ctx->bridge.of_node = dev->of_node;
713 	ctx->bridge.pre_enable_prev_first = true;
714 	drm_bridge_add(&ctx->bridge);
715 
716 	ret = sn65dsi83_host_attach(ctx);
717 	if (ret) {
718 		dev_err_probe(dev, ret, "failed to attach DSI host\n");
719 		goto err_remove_bridge;
720 	}
721 
722 	return 0;
723 
724 err_remove_bridge:
725 	drm_bridge_remove(&ctx->bridge);
726 	return ret;
727 }
728 
sn65dsi83_remove(struct i2c_client * client)729 static void sn65dsi83_remove(struct i2c_client *client)
730 {
731 	struct sn65dsi83 *ctx = i2c_get_clientdata(client);
732 
733 	drm_bridge_remove(&ctx->bridge);
734 }
735 
736 static struct i2c_device_id sn65dsi83_id[] = {
737 	{ "ti,sn65dsi83", MODEL_SN65DSI83 },
738 	{ "ti,sn65dsi84", MODEL_SN65DSI84 },
739 	{},
740 };
741 MODULE_DEVICE_TABLE(i2c, sn65dsi83_id);
742 
743 static const struct of_device_id sn65dsi83_match_table[] = {
744 	{ .compatible = "ti,sn65dsi83", .data = (void *)MODEL_SN65DSI83 },
745 	{ .compatible = "ti,sn65dsi84", .data = (void *)MODEL_SN65DSI84 },
746 	{},
747 };
748 MODULE_DEVICE_TABLE(of, sn65dsi83_match_table);
749 
750 static struct i2c_driver sn65dsi83_driver = {
751 	.probe = sn65dsi83_probe,
752 	.remove = sn65dsi83_remove,
753 	.id_table = sn65dsi83_id,
754 	.driver = {
755 		.name = "sn65dsi83",
756 		.of_match_table = sn65dsi83_match_table,
757 	},
758 };
759 module_i2c_driver(sn65dsi83_driver);
760 
761 MODULE_AUTHOR("Marek Vasut <marex@denx.de>");
762 MODULE_DESCRIPTION("TI SN65DSI83 DSI to LVDS bridge driver");
763 MODULE_LICENSE("GPL v2");
764