1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2020 Amarula Solutions(India)
4  * Author: Jagan Teki <jagan@amarulasolutions.com>
5  */
6 
7 #include <drm/drm_atomic_helper.h>
8 #include <drm/drm_of.h>
9 #include <drm/drm_print.h>
10 #include <drm/drm_mipi_dsi.h>
11 
12 #include <linux/bitfield.h>
13 #include <linux/bits.h>
14 #include <linux/clk.h>
15 #include <linux/delay.h>
16 #include <linux/gpio/consumer.h>
17 #include <linux/i2c.h>
18 #include <linux/media-bus-format.h>
19 #include <linux/module.h>
20 #include <linux/of.h>
21 #include <linux/regmap.h>
22 #include <linux/regulator/consumer.h>
23 
24 #define VENDOR_ID		0x00
25 #define DEVICE_ID_H		0x01
26 #define DEVICE_ID_L		0x02
27 #define VERSION_ID		0x03
28 #define FIRMWARE_VERSION	0x08
29 #define CONFIG_FINISH		0x09
30 #define PD_CTRL(n)		(0x0a + ((n) & 0x3)) /* 0..3 */
31 #define RST_CTRL(n)		(0x0e + ((n) & 0x1)) /* 0..1 */
32 #define SYS_CTRL(n)		(0x10 + ((n) & 0x7)) /* 0..4 */
33 #define SYS_CTRL_1_CLK_PHASE_MSK	GENMASK(5, 4)
34 #define CLK_PHASE_0			0
35 #define CLK_PHASE_1_4			1
36 #define CLK_PHASE_1_2			2
37 #define CLK_PHASE_3_4			3
38 #define RGB_DRV(n)		(0x18 + ((n) & 0x3)) /* 0..3 */
39 #define RGB_DLY(n)		(0x1c + ((n) & 0x1)) /* 0..1 */
40 #define RGB_TEST_CTRL		0x1e
41 #define ATE_PLL_EN		0x1f
42 #define HACTIVE_LI		0x20
43 #define VACTIVE_LI		0x21
44 #define VACTIVE_HACTIVE_HI	0x22
45 #define HFP_LI			0x23
46 #define HSYNC_LI		0x24
47 #define HBP_LI			0x25
48 #define HFP_HSW_HBP_HI		0x26
49 #define HFP_HSW_HBP_HI_HFP(n)		(((n) & 0x300) >> 4)
50 #define HFP_HSW_HBP_HI_HS(n)		(((n) & 0x300) >> 6)
51 #define HFP_HSW_HBP_HI_HBP(n)		(((n) & 0x300) >> 8)
52 #define VFP			0x27
53 #define VSYNC			0x28
54 #define VBP			0x29
55 #define BIST_POL		0x2a
56 #define BIST_POL_BIST_MODE(n)		(((n) & 0xf) << 4)
57 #define BIST_POL_BIST_GEN		BIT(3)
58 #define BIST_POL_HSYNC_POL		BIT(2)
59 #define BIST_POL_VSYNC_POL		BIT(1)
60 #define BIST_POL_DE_POL			BIT(0)
61 #define BIST_RED		0x2b
62 #define BIST_GREEN		0x2c
63 #define BIST_BLUE		0x2d
64 #define BIST_CHESS_X		0x2e
65 #define BIST_CHESS_Y		0x2f
66 #define BIST_CHESS_XY_H		0x30
67 #define BIST_FRAME_TIME_L	0x31
68 #define BIST_FRAME_TIME_H	0x32
69 #define FIFO_MAX_ADDR_LOW	0x33
70 #define SYNC_EVENT_DLY		0x34
71 #define HSW_MIN			0x35
72 #define HFP_MIN			0x36
73 #define LOGIC_RST_NUM		0x37
74 #define OSC_CTRL(n)		(0x48 + ((n) & 0x7)) /* 0..5 */
75 #define BG_CTRL			0x4e
76 #define LDO_PLL			0x4f
77 #define PLL_CTRL(n)		(0x50 + ((n) & 0xf)) /* 0..15 */
78 #define PLL_CTRL_6_EXTERNAL		0x90
79 #define PLL_CTRL_6_MIPI_CLK		0x92
80 #define PLL_CTRL_6_INTERNAL		0x93
81 #define PLL_REM(n)		(0x60 + ((n) & 0x3)) /* 0..2 */
82 #define PLL_DIV(n)		(0x63 + ((n) & 0x3)) /* 0..2 */
83 #define PLL_FRAC(n)		(0x66 + ((n) & 0x3)) /* 0..2 */
84 #define PLL_INT(n)		(0x69 + ((n) & 0x1)) /* 0..1 */
85 #define PLL_REF_DIV		0x6b
86 #define PLL_REF_DIV_P(n)		((n) & 0xf)
87 #define PLL_REF_DIV_Pe			BIT(4)
88 #define PLL_REF_DIV_S(n)		(((n) & 0x7) << 5)
89 #define PLL_SSC_P(n)		(0x6c + ((n) & 0x3)) /* 0..2 */
90 #define PLL_SSC_STEP(n)		(0x6f + ((n) & 0x3)) /* 0..2 */
91 #define PLL_SSC_OFFSET(n)	(0x72 + ((n) & 0x3)) /* 0..3 */
92 #define GPIO_OEN		0x79
93 #define MIPI_CFG_PW		0x7a
94 #define MIPI_CFG_PW_CONFIG_DSI		0xc1
95 #define MIPI_CFG_PW_CONFIG_I2C		0x3e
96 #define GPIO_SEL(n)		(0x7b + ((n) & 0x1)) /* 0..1 */
97 #define IRQ_SEL			0x7d
98 #define DBG_SEL			0x7e
99 #define DBG_SIGNAL		0x7f
100 #define MIPI_ERR_VECTOR_L	0x80
101 #define MIPI_ERR_VECTOR_H	0x81
102 #define MIPI_ERR_VECTOR_EN_L	0x82
103 #define MIPI_ERR_VECTOR_EN_H	0x83
104 #define MIPI_MAX_SIZE_L		0x84
105 #define MIPI_MAX_SIZE_H		0x85
106 #define DSI_CTRL		0x86
107 #define DSI_CTRL_UNKNOWN		0x28
108 #define DSI_CTRL_DSI_LANES(n)		((n) & 0x3)
109 #define MIPI_PN_SWAP		0x87
110 #define MIPI_PN_SWAP_CLK		BIT(4)
111 #define MIPI_PN_SWAP_D(n)		BIT((n) & 0x3)
112 #define MIPI_SOT_SYNC_BIT(n)	(0x88 + ((n) & 0x1)) /* 0..1 */
113 #define MIPI_ULPS_CTRL		0x8a
114 #define MIPI_CLK_CHK_VAR	0x8e
115 #define MIPI_CLK_CHK_INI	0x8f
116 #define MIPI_T_TERM_EN		0x90
117 #define MIPI_T_HS_SETTLE	0x91
118 #define MIPI_T_TA_SURE_PRE	0x92
119 #define MIPI_T_LPX_SET		0x94
120 #define MIPI_T_CLK_MISS		0x95
121 #define MIPI_INIT_TIME_L	0x96
122 #define MIPI_INIT_TIME_H	0x97
123 #define MIPI_T_CLK_TERM_EN	0x99
124 #define MIPI_T_CLK_SETTLE	0x9a
125 #define MIPI_TO_HS_RX_L		0x9e
126 #define MIPI_TO_HS_RX_H		0x9f
127 #define MIPI_PHY(n)		(0xa0 + ((n) & 0x7)) /* 0..5 */
128 #define MIPI_PD_RX		0xb0
129 #define MIPI_PD_TERM		0xb1
130 #define MIPI_PD_HSRX		0xb2
131 #define MIPI_PD_LPTX		0xb3
132 #define MIPI_PD_LPRX		0xb4
133 #define MIPI_PD_CK_LANE		0xb5
134 #define MIPI_FORCE_0		0xb6
135 #define MIPI_RST_CTRL		0xb7
136 #define MIPI_RST_NUM		0xb8
137 #define MIPI_DBG_SET(n)		(0xc0 + ((n) & 0xf)) /* 0..9 */
138 #define MIPI_DBG_SEL		0xe0
139 #define MIPI_DBG_DATA		0xe1
140 #define MIPI_ATE_TEST_SEL	0xe2
141 #define MIPI_ATE_STATUS(n)	(0xe3 + ((n) & 0x1)) /* 0..1 */
142 
143 struct chipone {
144 	struct device *dev;
145 	struct regmap *regmap;
146 	struct i2c_client *client;
147 	struct drm_bridge bridge;
148 	struct drm_display_mode mode;
149 	struct drm_bridge *panel_bridge;
150 	struct mipi_dsi_device *dsi;
151 	struct gpio_desc *enable_gpio;
152 	struct regulator *vdd1;
153 	struct regulator *vdd2;
154 	struct regulator *vdd3;
155 	struct clk *refclk;
156 	unsigned long refclk_rate;
157 	bool interface_i2c;
158 };
159 
160 static const struct regmap_range chipone_dsi_readable_ranges[] = {
161 	regmap_reg_range(VENDOR_ID, VERSION_ID),
162 	regmap_reg_range(FIRMWARE_VERSION, PLL_SSC_OFFSET(3)),
163 	regmap_reg_range(GPIO_OEN, MIPI_ULPS_CTRL),
164 	regmap_reg_range(MIPI_CLK_CHK_VAR, MIPI_T_TA_SURE_PRE),
165 	regmap_reg_range(MIPI_T_LPX_SET, MIPI_INIT_TIME_H),
166 	regmap_reg_range(MIPI_T_CLK_TERM_EN, MIPI_T_CLK_SETTLE),
167 	regmap_reg_range(MIPI_TO_HS_RX_L, MIPI_PHY(5)),
168 	regmap_reg_range(MIPI_PD_RX, MIPI_RST_NUM),
169 	regmap_reg_range(MIPI_DBG_SET(0), MIPI_DBG_SET(9)),
170 	regmap_reg_range(MIPI_DBG_SEL, MIPI_ATE_STATUS(1)),
171 };
172 
173 static const struct regmap_access_table chipone_dsi_readable_table = {
174 	.yes_ranges = chipone_dsi_readable_ranges,
175 	.n_yes_ranges = ARRAY_SIZE(chipone_dsi_readable_ranges),
176 };
177 
178 static const struct regmap_range chipone_dsi_writeable_ranges[] = {
179 	regmap_reg_range(CONFIG_FINISH, PLL_SSC_OFFSET(3)),
180 	regmap_reg_range(GPIO_OEN, MIPI_ULPS_CTRL),
181 	regmap_reg_range(MIPI_CLK_CHK_VAR, MIPI_T_TA_SURE_PRE),
182 	regmap_reg_range(MIPI_T_LPX_SET, MIPI_INIT_TIME_H),
183 	regmap_reg_range(MIPI_T_CLK_TERM_EN, MIPI_T_CLK_SETTLE),
184 	regmap_reg_range(MIPI_TO_HS_RX_L, MIPI_PHY(5)),
185 	regmap_reg_range(MIPI_PD_RX, MIPI_RST_NUM),
186 	regmap_reg_range(MIPI_DBG_SET(0), MIPI_DBG_SET(9)),
187 	regmap_reg_range(MIPI_DBG_SEL, MIPI_ATE_STATUS(1)),
188 };
189 
190 static const struct regmap_access_table chipone_dsi_writeable_table = {
191 	.yes_ranges = chipone_dsi_writeable_ranges,
192 	.n_yes_ranges = ARRAY_SIZE(chipone_dsi_writeable_ranges),
193 };
194 
195 static const struct regmap_config chipone_regmap_config = {
196 	.reg_bits = 8,
197 	.val_bits = 8,
198 	.rd_table = &chipone_dsi_readable_table,
199 	.wr_table = &chipone_dsi_writeable_table,
200 	.cache_type = REGCACHE_RBTREE,
201 	.max_register = MIPI_ATE_STATUS(1),
202 };
203 
204 static int chipone_dsi_read(void *context,
205 			    const void *reg, size_t reg_size,
206 			    void *val, size_t val_size)
207 {
208 	struct mipi_dsi_device *dsi = context;
209 	const u16 reg16 = (val_size << 8) | *(u8 *)reg;
210 	int ret;
211 
212 	ret = mipi_dsi_generic_read(dsi, &reg16, 2, val, val_size);
213 
214 	return ret == val_size ? 0 : -EINVAL;
215 }
216 
217 static int chipone_dsi_write(void *context, const void *data, size_t count)
218 {
219 	struct mipi_dsi_device *dsi = context;
220 
221 	return mipi_dsi_generic_write(dsi, data, 2);
222 }
223 
224 static const struct regmap_bus chipone_dsi_regmap_bus = {
225 	.read				= chipone_dsi_read,
226 	.write				= chipone_dsi_write,
227 	.reg_format_endian_default	= REGMAP_ENDIAN_NATIVE,
228 	.val_format_endian_default	= REGMAP_ENDIAN_NATIVE,
229 };
230 
231 static inline struct chipone *bridge_to_chipone(struct drm_bridge *bridge)
232 {
233 	return container_of(bridge, struct chipone, bridge);
234 }
235 
236 static void chipone_readb(struct chipone *icn, u8 reg, u8 *val)
237 {
238 	int ret, pval;
239 
240 	ret = regmap_read(icn->regmap, reg, &pval);
241 
242 	*val = ret ? 0 : pval & 0xff;
243 }
244 
245 static int chipone_writeb(struct chipone *icn, u8 reg, u8 val)
246 {
247 	return regmap_write(icn->regmap, reg, val);
248 }
249 
250 static void chipone_configure_pll(struct chipone *icn,
251 				  const struct drm_display_mode *mode)
252 {
253 	unsigned int best_p = 0, best_m = 0, best_s = 0;
254 	unsigned int mode_clock = mode->clock * 1000;
255 	unsigned int delta, min_delta = 0xffffffff;
256 	unsigned int freq_p, freq_s, freq_out;
257 	unsigned int p_min, p_max;
258 	unsigned int p, m, s;
259 	unsigned int fin;
260 	bool best_p_pot;
261 	u8 ref_div;
262 
263 	/*
264 	 * DSI byte clock frequency (input into PLL) is calculated as:
265 	 *  DSI_CLK = HS clock / 4
266 	 *
267 	 * DPI pixel clock frequency (output from PLL) is mode clock.
268 	 *
269 	 * The chip contains fractional PLL which works as follows:
270 	 *  DPI_CLK = ((DSI_CLK / P) * M) / S
271 	 * P is pre-divider, register PLL_REF_DIV[3:0] is 1:n divider
272 	 *                   register PLL_REF_DIV[4] is extra 1:2 divider
273 	 * M is integer multiplier, register PLL_INT(0) is multiplier
274 	 * S is post-divider, register PLL_REF_DIV[7:5] is 2^(n+1) divider
275 	 *
276 	 * It seems the PLL input clock after applying P pre-divider have
277 	 * to be lower than 20 MHz.
278 	 */
279 	if (icn->refclk)
280 		fin = icn->refclk_rate;
281 	else
282 		fin = icn->dsi->hs_rate / 4; /* in Hz */
283 
284 	/* Minimum value of P predivider for PLL input in 5..20 MHz */
285 	p_min = clamp(DIV_ROUND_UP(fin, 20000000), 1U, 31U);
286 	p_max = clamp(fin / 5000000, 1U, 31U);
287 
288 	for (p = p_min; p < p_max; p++) {	/* PLL_REF_DIV[4,3:0] */
289 		if (p > 16 && p & 1)		/* P > 16 uses extra /2 */
290 			continue;
291 		freq_p = fin / p;
292 		if (freq_p == 0)		/* Divider too high */
293 			break;
294 
295 		for (s = 0; s < 0x7; s++) {	/* PLL_REF_DIV[7:5] */
296 			freq_s = freq_p / BIT(s + 1);
297 			if (freq_s == 0)	/* Divider too high */
298 				break;
299 
300 			m = mode_clock / freq_s;
301 
302 			/* Multiplier is 8 bit */
303 			if (m > 0xff)
304 				continue;
305 
306 			/* Limit PLL VCO frequency to 1 GHz */
307 			freq_out = (fin * m) / p;
308 			if (freq_out > 1000000000)
309 				continue;
310 
311 			/* Apply post-divider */
312 			freq_out /= BIT(s + 1);
313 
314 			delta = abs(mode_clock - freq_out);
315 			if (delta < min_delta) {
316 				best_p = p;
317 				best_m = m;
318 				best_s = s;
319 				min_delta = delta;
320 			}
321 		}
322 	}
323 
324 	best_p_pot = !(best_p & 1);
325 
326 	dev_dbg(icn->dev,
327 		"PLL: P[3:0]=%d P[4]=2*%d M=%d S[7:5]=2^%d delta=%d => DSI f_in(%s)=%d Hz ; DPI f_out=%d Hz\n",
328 		best_p >> best_p_pot, best_p_pot, best_m, best_s + 1,
329 		min_delta, icn->refclk ? "EXT" : "DSI", fin,
330 		(fin * best_m) / (best_p << (best_s + 1)));
331 
332 	ref_div = PLL_REF_DIV_P(best_p >> best_p_pot) | PLL_REF_DIV_S(best_s);
333 	if (best_p_pot)	/* Prefer /2 pre-divider */
334 		ref_div |= PLL_REF_DIV_Pe;
335 
336 	/* Clock source selection either external clock or MIPI DSI clock lane */
337 	chipone_writeb(icn, PLL_CTRL(6),
338 		       icn->refclk ? PLL_CTRL_6_EXTERNAL : PLL_CTRL_6_MIPI_CLK);
339 	chipone_writeb(icn, PLL_REF_DIV, ref_div);
340 	chipone_writeb(icn, PLL_INT(0), best_m);
341 }
342 
343 static void chipone_atomic_enable(struct drm_bridge *bridge,
344 				  struct drm_bridge_state *old_bridge_state)
345 {
346 	struct chipone *icn = bridge_to_chipone(bridge);
347 	struct drm_atomic_state *state = old_bridge_state->base.state;
348 	struct drm_display_mode *mode = &icn->mode;
349 	const struct drm_bridge_state *bridge_state;
350 	u16 hfp, hbp, hsync;
351 	u32 bus_flags;
352 	u8 pol, sys_ctrl_1, id[4];
353 
354 	chipone_readb(icn, VENDOR_ID, id);
355 	chipone_readb(icn, DEVICE_ID_H, id + 1);
356 	chipone_readb(icn, DEVICE_ID_L, id + 2);
357 	chipone_readb(icn, VERSION_ID, id + 3);
358 
359 	dev_dbg(icn->dev,
360 		"Chip IDs: Vendor=0x%02x Device=0x%02x:0x%02x Version=0x%02x\n",
361 		id[0], id[1], id[2], id[3]);
362 
363 	if (id[0] != 0xc1 || id[1] != 0x62 || id[2] != 0x11) {
364 		dev_dbg(icn->dev, "Invalid Chip IDs, aborting configuration\n");
365 		return;
366 	}
367 
368 	/* Get the DPI flags from the bridge state. */
369 	bridge_state = drm_atomic_get_new_bridge_state(state, bridge);
370 	bus_flags = bridge_state->output_bus_cfg.flags;
371 
372 	if (icn->interface_i2c)
373 		chipone_writeb(icn, MIPI_CFG_PW, MIPI_CFG_PW_CONFIG_I2C);
374 	else
375 		chipone_writeb(icn, MIPI_CFG_PW, MIPI_CFG_PW_CONFIG_DSI);
376 
377 	chipone_writeb(icn, HACTIVE_LI, mode->hdisplay & 0xff);
378 
379 	chipone_writeb(icn, VACTIVE_LI, mode->vdisplay & 0xff);
380 
381 	/*
382 	 * lsb nibble: 2nd nibble of hdisplay
383 	 * msb nibble: 2nd nibble of vdisplay
384 	 */
385 	chipone_writeb(icn, VACTIVE_HACTIVE_HI,
386 		       ((mode->hdisplay >> 8) & 0xf) |
387 		       (((mode->vdisplay >> 8) & 0xf) << 4));
388 
389 	hfp = mode->hsync_start - mode->hdisplay;
390 	hsync = mode->hsync_end - mode->hsync_start;
391 	hbp = mode->htotal - mode->hsync_end;
392 
393 	chipone_writeb(icn, HFP_LI, hfp & 0xff);
394 	chipone_writeb(icn, HSYNC_LI, hsync & 0xff);
395 	chipone_writeb(icn, HBP_LI, hbp & 0xff);
396 	/* Top two bits of Horizontal Front porch/Sync/Back porch */
397 	chipone_writeb(icn, HFP_HSW_HBP_HI,
398 		       HFP_HSW_HBP_HI_HFP(hfp) |
399 		       HFP_HSW_HBP_HI_HS(hsync) |
400 		       HFP_HSW_HBP_HI_HBP(hbp));
401 
402 	chipone_writeb(icn, VFP, mode->vsync_start - mode->vdisplay);
403 
404 	chipone_writeb(icn, VSYNC, mode->vsync_end - mode->vsync_start);
405 
406 	chipone_writeb(icn, VBP, mode->vtotal - mode->vsync_end);
407 
408 	/* dsi specific sequence */
409 	chipone_writeb(icn, SYNC_EVENT_DLY, 0x80);
410 	chipone_writeb(icn, HFP_MIN, hfp & 0xff);
411 
412 	/* DSI data lane count */
413 	chipone_writeb(icn, DSI_CTRL,
414 		       DSI_CTRL_UNKNOWN | DSI_CTRL_DSI_LANES(icn->dsi->lanes - 1));
415 
416 	chipone_writeb(icn, MIPI_PD_CK_LANE, 0xa0);
417 	chipone_writeb(icn, PLL_CTRL(12), 0xff);
418 	chipone_writeb(icn, MIPI_PN_SWAP, 0x00);
419 
420 	/* DPI HS/VS/DE polarity */
421 	pol = ((mode->flags & DRM_MODE_FLAG_PHSYNC) ? BIST_POL_HSYNC_POL : 0) |
422 	      ((mode->flags & DRM_MODE_FLAG_PVSYNC) ? BIST_POL_VSYNC_POL : 0) |
423 	      ((bus_flags & DRM_BUS_FLAG_DE_HIGH) ? BIST_POL_DE_POL : 0);
424 	chipone_writeb(icn, BIST_POL, pol);
425 
426 	/* Configure PLL settings */
427 	chipone_configure_pll(icn, mode);
428 
429 	chipone_writeb(icn, SYS_CTRL(0), 0x40);
430 	sys_ctrl_1 = 0x88;
431 
432 	if (bus_flags & DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE)
433 		sys_ctrl_1 |= FIELD_PREP(SYS_CTRL_1_CLK_PHASE_MSK, CLK_PHASE_0);
434 	else
435 		sys_ctrl_1 |= FIELD_PREP(SYS_CTRL_1_CLK_PHASE_MSK, CLK_PHASE_1_2);
436 
437 	chipone_writeb(icn, SYS_CTRL(1), sys_ctrl_1);
438 
439 	/* icn6211 specific sequence */
440 	chipone_writeb(icn, MIPI_FORCE_0, 0x20);
441 	chipone_writeb(icn, PLL_CTRL(1), 0x20);
442 	chipone_writeb(icn, CONFIG_FINISH, 0x10);
443 
444 	usleep_range(10000, 11000);
445 }
446 
447 static void chipone_atomic_pre_enable(struct drm_bridge *bridge,
448 				      struct drm_bridge_state *old_bridge_state)
449 {
450 	struct chipone *icn = bridge_to_chipone(bridge);
451 	int ret;
452 
453 	if (icn->vdd1) {
454 		ret = regulator_enable(icn->vdd1);
455 		if (ret)
456 			DRM_DEV_ERROR(icn->dev,
457 				      "failed to enable VDD1 regulator: %d\n", ret);
458 	}
459 
460 	if (icn->vdd2) {
461 		ret = regulator_enable(icn->vdd2);
462 		if (ret)
463 			DRM_DEV_ERROR(icn->dev,
464 				      "failed to enable VDD2 regulator: %d\n", ret);
465 	}
466 
467 	if (icn->vdd3) {
468 		ret = regulator_enable(icn->vdd3);
469 		if (ret)
470 			DRM_DEV_ERROR(icn->dev,
471 				      "failed to enable VDD3 regulator: %d\n", ret);
472 	}
473 
474 	ret = clk_prepare_enable(icn->refclk);
475 	if (ret)
476 		DRM_DEV_ERROR(icn->dev,
477 			      "failed to enable RECLK clock: %d\n", ret);
478 
479 	gpiod_set_value(icn->enable_gpio, 1);
480 
481 	usleep_range(10000, 11000);
482 }
483 
484 static void chipone_atomic_post_disable(struct drm_bridge *bridge,
485 					struct drm_bridge_state *old_bridge_state)
486 {
487 	struct chipone *icn = bridge_to_chipone(bridge);
488 
489 	clk_disable_unprepare(icn->refclk);
490 
491 	if (icn->vdd1)
492 		regulator_disable(icn->vdd1);
493 
494 	if (icn->vdd2)
495 		regulator_disable(icn->vdd2);
496 
497 	if (icn->vdd3)
498 		regulator_disable(icn->vdd3);
499 
500 	gpiod_set_value(icn->enable_gpio, 0);
501 }
502 
503 static void chipone_mode_set(struct drm_bridge *bridge,
504 			     const struct drm_display_mode *mode,
505 			     const struct drm_display_mode *adjusted_mode)
506 {
507 	struct chipone *icn = bridge_to_chipone(bridge);
508 
509 	drm_mode_copy(&icn->mode, adjusted_mode);
510 };
511 
512 static int chipone_dsi_attach(struct chipone *icn)
513 {
514 	struct mipi_dsi_device *dsi = icn->dsi;
515 	struct device *dev = icn->dev;
516 	int dsi_lanes, ret;
517 
518 	dsi_lanes = drm_of_get_data_lanes_count_ep(dev->of_node, 0, 0, 1, 4);
519 
520 	/*
521 	 * If the 'data-lanes' property does not exist in DT or is invalid,
522 	 * default to previously hard-coded behavior, which was 4 data lanes.
523 	 */
524 	if (dsi_lanes < 0)
525 		icn->dsi->lanes = 4;
526 	else
527 		icn->dsi->lanes = dsi_lanes;
528 
529 	dsi->format = MIPI_DSI_FMT_RGB888;
530 	dsi->mode_flags = MIPI_DSI_MODE_VIDEO | MIPI_DSI_MODE_VIDEO_BURST |
531 			  MIPI_DSI_MODE_LPM | MIPI_DSI_MODE_NO_EOT_PACKET;
532 	dsi->hs_rate = 500000000;
533 	dsi->lp_rate = 16000000;
534 
535 	ret = mipi_dsi_attach(dsi);
536 	if (ret < 0)
537 		dev_err(icn->dev, "failed to attach dsi\n");
538 
539 	return ret;
540 }
541 
542 static int chipone_dsi_host_attach(struct chipone *icn)
543 {
544 	struct device *dev = icn->dev;
545 	struct device_node *host_node;
546 	struct device_node *endpoint;
547 	struct mipi_dsi_device *dsi;
548 	struct mipi_dsi_host *host;
549 	int ret = 0;
550 
551 	const struct mipi_dsi_device_info info = {
552 		.type = "chipone",
553 		.channel = 0,
554 		.node = NULL,
555 	};
556 
557 	endpoint = of_graph_get_endpoint_by_regs(dev->of_node, 0, 0);
558 	host_node = of_graph_get_remote_port_parent(endpoint);
559 	of_node_put(endpoint);
560 
561 	if (!host_node)
562 		return -EINVAL;
563 
564 	host = of_find_mipi_dsi_host_by_node(host_node);
565 	of_node_put(host_node);
566 	if (!host)
567 		return dev_err_probe(dev, -EPROBE_DEFER, "failed to find dsi host\n");
568 
569 	dsi = mipi_dsi_device_register_full(host, &info);
570 	if (IS_ERR(dsi)) {
571 		return dev_err_probe(dev, PTR_ERR(dsi),
572 				     "failed to create dsi device\n");
573 	}
574 
575 	icn->dsi = dsi;
576 
577 	ret = chipone_dsi_attach(icn);
578 	if (ret < 0)
579 		mipi_dsi_device_unregister(dsi);
580 
581 	return ret;
582 }
583 
584 static int chipone_attach(struct drm_bridge *bridge, enum drm_bridge_attach_flags flags)
585 {
586 	struct chipone *icn = bridge_to_chipone(bridge);
587 
588 	return drm_bridge_attach(bridge->encoder, icn->panel_bridge, bridge, flags);
589 }
590 
591 #define MAX_INPUT_SEL_FORMATS	1
592 
593 static u32 *
594 chipone_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
595 				  struct drm_bridge_state *bridge_state,
596 				  struct drm_crtc_state *crtc_state,
597 				  struct drm_connector_state *conn_state,
598 				  u32 output_fmt,
599 				  unsigned int *num_input_fmts)
600 {
601 	u32 *input_fmts;
602 
603 	*num_input_fmts = 0;
604 
605 	input_fmts = kcalloc(MAX_INPUT_SEL_FORMATS, sizeof(*input_fmts),
606 			     GFP_KERNEL);
607 	if (!input_fmts)
608 		return NULL;
609 
610 	/* This is the DSI-end bus format */
611 	input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X24;
612 	*num_input_fmts = 1;
613 
614 	return input_fmts;
615 }
616 
617 static const struct drm_bridge_funcs chipone_bridge_funcs = {
618 	.atomic_duplicate_state	= drm_atomic_helper_bridge_duplicate_state,
619 	.atomic_destroy_state	= drm_atomic_helper_bridge_destroy_state,
620 	.atomic_reset		= drm_atomic_helper_bridge_reset,
621 	.atomic_pre_enable	= chipone_atomic_pre_enable,
622 	.atomic_enable		= chipone_atomic_enable,
623 	.atomic_post_disable	= chipone_atomic_post_disable,
624 	.mode_set		= chipone_mode_set,
625 	.attach			= chipone_attach,
626 	.atomic_get_input_bus_fmts = chipone_atomic_get_input_bus_fmts,
627 };
628 
629 static int chipone_parse_dt(struct chipone *icn)
630 {
631 	struct device *dev = icn->dev;
632 	int ret;
633 
634 	icn->refclk = devm_clk_get_optional(dev, "refclk");
635 	if (IS_ERR(icn->refclk)) {
636 		ret = PTR_ERR(icn->refclk);
637 		DRM_DEV_ERROR(dev, "failed to get REFCLK clock: %d\n", ret);
638 		return ret;
639 	} else if (icn->refclk) {
640 		icn->refclk_rate = clk_get_rate(icn->refclk);
641 		if (icn->refclk_rate < 10000000 || icn->refclk_rate > 154000000) {
642 			DRM_DEV_ERROR(dev, "REFCLK out of range: %ld Hz\n",
643 				      icn->refclk_rate);
644 			return -EINVAL;
645 		}
646 	}
647 
648 	icn->vdd1 = devm_regulator_get_optional(dev, "vdd1");
649 	if (IS_ERR(icn->vdd1)) {
650 		ret = PTR_ERR(icn->vdd1);
651 		if (ret == -EPROBE_DEFER)
652 			return -EPROBE_DEFER;
653 		icn->vdd1 = NULL;
654 		DRM_DEV_DEBUG(dev, "failed to get VDD1 regulator: %d\n", ret);
655 	}
656 
657 	icn->vdd2 = devm_regulator_get_optional(dev, "vdd2");
658 	if (IS_ERR(icn->vdd2)) {
659 		ret = PTR_ERR(icn->vdd2);
660 		if (ret == -EPROBE_DEFER)
661 			return -EPROBE_DEFER;
662 		icn->vdd2 = NULL;
663 		DRM_DEV_DEBUG(dev, "failed to get VDD2 regulator: %d\n", ret);
664 	}
665 
666 	icn->vdd3 = devm_regulator_get_optional(dev, "vdd3");
667 	if (IS_ERR(icn->vdd3)) {
668 		ret = PTR_ERR(icn->vdd3);
669 		if (ret == -EPROBE_DEFER)
670 			return -EPROBE_DEFER;
671 		icn->vdd3 = NULL;
672 		DRM_DEV_DEBUG(dev, "failed to get VDD3 regulator: %d\n", ret);
673 	}
674 
675 	icn->enable_gpio = devm_gpiod_get(dev, "enable", GPIOD_OUT_LOW);
676 	if (IS_ERR(icn->enable_gpio)) {
677 		DRM_DEV_ERROR(dev, "failed to get enable GPIO\n");
678 		return PTR_ERR(icn->enable_gpio);
679 	}
680 
681 	icn->panel_bridge = devm_drm_of_get_bridge(dev, dev->of_node, 1, 0);
682 	if (IS_ERR(icn->panel_bridge))
683 		return PTR_ERR(icn->panel_bridge);
684 
685 	return 0;
686 }
687 
688 static int chipone_common_probe(struct device *dev, struct chipone **icnr)
689 {
690 	struct chipone *icn;
691 	int ret;
692 
693 	icn = devm_kzalloc(dev, sizeof(struct chipone), GFP_KERNEL);
694 	if (!icn)
695 		return -ENOMEM;
696 
697 	icn->dev = dev;
698 
699 	ret = chipone_parse_dt(icn);
700 	if (ret)
701 		return ret;
702 
703 	icn->bridge.funcs = &chipone_bridge_funcs;
704 	icn->bridge.type = DRM_MODE_CONNECTOR_DPI;
705 	icn->bridge.of_node = dev->of_node;
706 
707 	*icnr = icn;
708 
709 	return ret;
710 }
711 
712 static int chipone_dsi_probe(struct mipi_dsi_device *dsi)
713 {
714 	struct device *dev = &dsi->dev;
715 	struct chipone *icn;
716 	int ret;
717 
718 	ret = chipone_common_probe(dev, &icn);
719 	if (ret)
720 		return ret;
721 
722 	icn->regmap = devm_regmap_init(dev, &chipone_dsi_regmap_bus,
723 				       dsi, &chipone_regmap_config);
724 	if (IS_ERR(icn->regmap))
725 		return PTR_ERR(icn->regmap);
726 
727 	icn->interface_i2c = false;
728 	icn->dsi = dsi;
729 
730 	mipi_dsi_set_drvdata(dsi, icn);
731 
732 	drm_bridge_add(&icn->bridge);
733 
734 	ret = chipone_dsi_attach(icn);
735 	if (ret)
736 		drm_bridge_remove(&icn->bridge);
737 
738 	return ret;
739 }
740 
741 static int chipone_i2c_probe(struct i2c_client *client)
742 {
743 	struct device *dev = &client->dev;
744 	struct chipone *icn;
745 	int ret;
746 
747 	ret = chipone_common_probe(dev, &icn);
748 	if (ret)
749 		return ret;
750 
751 	icn->regmap = devm_regmap_init_i2c(client, &chipone_regmap_config);
752 	if (IS_ERR(icn->regmap))
753 		return PTR_ERR(icn->regmap);
754 
755 	icn->interface_i2c = true;
756 	icn->client = client;
757 	dev_set_drvdata(dev, icn);
758 	i2c_set_clientdata(client, icn);
759 
760 	drm_bridge_add(&icn->bridge);
761 
762 	return chipone_dsi_host_attach(icn);
763 }
764 
765 static void chipone_dsi_remove(struct mipi_dsi_device *dsi)
766 {
767 	struct chipone *icn = mipi_dsi_get_drvdata(dsi);
768 
769 	mipi_dsi_detach(dsi);
770 	drm_bridge_remove(&icn->bridge);
771 }
772 
773 static const struct of_device_id chipone_of_match[] = {
774 	{ .compatible = "chipone,icn6211", },
775 	{ /* sentinel */ }
776 };
777 MODULE_DEVICE_TABLE(of, chipone_of_match);
778 
779 static struct mipi_dsi_driver chipone_dsi_driver = {
780 	.probe = chipone_dsi_probe,
781 	.remove = chipone_dsi_remove,
782 	.driver = {
783 		.name = "chipone-icn6211",
784 		.owner = THIS_MODULE,
785 		.of_match_table = chipone_of_match,
786 	},
787 };
788 
789 static struct i2c_device_id chipone_i2c_id[] = {
790 	{ "chipone,icn6211" },
791 	{},
792 };
793 MODULE_DEVICE_TABLE(i2c, chipone_i2c_id);
794 
795 static struct i2c_driver chipone_i2c_driver = {
796 	.probe = chipone_i2c_probe,
797 	.id_table = chipone_i2c_id,
798 	.driver = {
799 		.name = "chipone-icn6211-i2c",
800 		.of_match_table = chipone_of_match,
801 	},
802 };
803 
804 static int __init chipone_init(void)
805 {
806 	if (IS_ENABLED(CONFIG_DRM_MIPI_DSI))
807 		mipi_dsi_driver_register(&chipone_dsi_driver);
808 
809 	return i2c_add_driver(&chipone_i2c_driver);
810 }
811 module_init(chipone_init);
812 
813 static void __exit chipone_exit(void)
814 {
815 	i2c_del_driver(&chipone_i2c_driver);
816 
817 	if (IS_ENABLED(CONFIG_DRM_MIPI_DSI))
818 		mipi_dsi_driver_unregister(&chipone_dsi_driver);
819 }
820 module_exit(chipone_exit);
821 
822 MODULE_AUTHOR("Jagan Teki <jagan@amarulasolutions.com>");
823 MODULE_DESCRIPTION("Chipone ICN6211 MIPI-DSI to RGB Converter Bridge");
824 MODULE_LICENSE("GPL");
825