1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2020 BayLibre, SAS
4  * Author: Phong LE <ple@baylibre.com>
5  * Copyright (C) 2018-2019, Artem Mygaiev
6  * Copyright (C) 2017, Fresco Logic, Incorporated.
7  *
8  */
9 
10 #include <linux/media-bus-format.h>
11 #include <linux/module.h>
12 #include <linux/device.h>
13 #include <linux/interrupt.h>
14 #include <linux/i2c.h>
15 #include <linux/bitfield.h>
16 #include <linux/property.h>
17 #include <linux/regmap.h>
18 #include <linux/of_graph.h>
19 #include <linux/gpio/consumer.h>
20 #include <linux/pinctrl/consumer.h>
21 #include <linux/regulator/consumer.h>
22 
23 #include <drm/drm_atomic_helper.h>
24 #include <drm/drm_bridge.h>
25 #include <drm/drm_edid.h>
26 #include <drm/drm_modes.h>
27 #include <drm/drm_print.h>
28 #include <drm/drm_probe_helper.h>
29 
30 #include <sound/hdmi-codec.h>
31 
32 #define IT66121_VENDOR_ID0_REG			0x00
33 #define IT66121_VENDOR_ID1_REG			0x01
34 #define IT66121_DEVICE_ID0_REG			0x02
35 #define IT66121_DEVICE_ID1_REG			0x03
36 
37 #define IT66121_REVISION_MASK			GENMASK(7, 4)
38 #define IT66121_DEVICE_ID1_MASK			GENMASK(3, 0)
39 
40 #define IT66121_MASTER_SEL_REG			0x10
41 #define IT66121_MASTER_SEL_HOST			BIT(0)
42 
43 #define IT66121_AFE_DRV_REG			0x61
44 #define IT66121_AFE_DRV_RST			BIT(4)
45 #define IT66121_AFE_DRV_PWD			BIT(5)
46 
47 #define IT66121_INPUT_MODE_REG			0x70
48 #define IT66121_INPUT_MODE_RGB			(0 << 6)
49 #define IT66121_INPUT_MODE_YUV422		BIT(6)
50 #define IT66121_INPUT_MODE_YUV444		(2 << 6)
51 #define IT66121_INPUT_MODE_CCIR656		BIT(4)
52 #define IT66121_INPUT_MODE_SYNCEMB		BIT(3)
53 #define IT66121_INPUT_MODE_DDR			BIT(2)
54 
55 #define IT66121_INPUT_CSC_REG			0x72
56 #define IT66121_INPUT_CSC_ENDITHER		BIT(7)
57 #define IT66121_INPUT_CSC_ENUDFILTER		BIT(6)
58 #define IT66121_INPUT_CSC_DNFREE_GO		BIT(5)
59 #define IT66121_INPUT_CSC_RGB_TO_YUV		0x02
60 #define IT66121_INPUT_CSC_YUV_TO_RGB		0x03
61 #define IT66121_INPUT_CSC_NO_CONV		0x00
62 
63 #define IT66121_AFE_XP_REG			0x62
64 #define IT66121_AFE_XP_GAINBIT			BIT(7)
65 #define IT66121_AFE_XP_PWDPLL			BIT(6)
66 #define IT66121_AFE_XP_ENI			BIT(5)
67 #define IT66121_AFE_XP_ENO			BIT(4)
68 #define IT66121_AFE_XP_RESETB			BIT(3)
69 #define IT66121_AFE_XP_PWDI			BIT(2)
70 #define IT6610_AFE_XP_BYPASS			BIT(0)
71 
72 #define IT66121_AFE_IP_REG			0x64
73 #define IT66121_AFE_IP_GAINBIT			BIT(7)
74 #define IT66121_AFE_IP_PWDPLL			BIT(6)
75 #define IT66121_AFE_IP_CKSEL_05			(0 << 4)
76 #define IT66121_AFE_IP_CKSEL_1			BIT(4)
77 #define IT66121_AFE_IP_CKSEL_2			(2 << 4)
78 #define IT66121_AFE_IP_CKSEL_2OR4		(3 << 4)
79 #define IT66121_AFE_IP_ER0			BIT(3)
80 #define IT66121_AFE_IP_RESETB			BIT(2)
81 #define IT66121_AFE_IP_ENC			BIT(1)
82 #define IT66121_AFE_IP_EC1			BIT(0)
83 
84 #define IT66121_AFE_XP_EC1_REG			0x68
85 #define IT66121_AFE_XP_EC1_LOWCLK		BIT(4)
86 
87 #define IT66121_SW_RST_REG			0x04
88 #define IT66121_SW_RST_REF			BIT(5)
89 #define IT66121_SW_RST_AREF			BIT(4)
90 #define IT66121_SW_RST_VID			BIT(3)
91 #define IT66121_SW_RST_AUD			BIT(2)
92 #define IT66121_SW_RST_HDCP			BIT(0)
93 
94 #define IT66121_DDC_COMMAND_REG			0x15
95 #define IT66121_DDC_COMMAND_BURST_READ		0x0
96 #define IT66121_DDC_COMMAND_EDID_READ		0x3
97 #define IT66121_DDC_COMMAND_FIFO_CLR		0x9
98 #define IT66121_DDC_COMMAND_SCL_PULSE		0xA
99 #define IT66121_DDC_COMMAND_ABORT		0xF
100 
101 #define IT66121_HDCP_REG			0x20
102 #define IT66121_HDCP_CPDESIRED			BIT(0)
103 #define IT66121_HDCP_EN1P1FEAT			BIT(1)
104 
105 #define IT66121_INT_STATUS1_REG			0x06
106 #define IT66121_INT_STATUS1_AUD_OVF		BIT(7)
107 #define IT66121_INT_STATUS1_DDC_NOACK		BIT(5)
108 #define IT66121_INT_STATUS1_DDC_FIFOERR		BIT(4)
109 #define IT66121_INT_STATUS1_DDC_BUSHANG		BIT(2)
110 #define IT66121_INT_STATUS1_RX_SENS_STATUS	BIT(1)
111 #define IT66121_INT_STATUS1_HPD_STATUS		BIT(0)
112 
113 #define IT66121_DDC_HEADER_REG			0x11
114 #define IT66121_DDC_HEADER_HDCP			0x74
115 #define IT66121_DDC_HEADER_EDID			0xA0
116 
117 #define IT66121_DDC_OFFSET_REG			0x12
118 #define IT66121_DDC_BYTE_REG			0x13
119 #define IT66121_DDC_SEGMENT_REG			0x14
120 #define IT66121_DDC_RD_FIFO_REG			0x17
121 
122 #define IT66121_CLK_BANK_REG			0x0F
123 #define IT66121_CLK_BANK_PWROFF_RCLK		BIT(6)
124 #define IT66121_CLK_BANK_PWROFF_ACLK		BIT(5)
125 #define IT66121_CLK_BANK_PWROFF_TXCLK		BIT(4)
126 #define IT66121_CLK_BANK_PWROFF_CRCLK		BIT(3)
127 #define IT66121_CLK_BANK_0			0
128 #define IT66121_CLK_BANK_1			1
129 
130 #define IT66121_INT_REG				0x05
131 #define IT66121_INT_ACTIVE_HIGH			BIT(7)
132 #define IT66121_INT_OPEN_DRAIN			BIT(6)
133 #define IT66121_INT_TX_CLK_OFF			BIT(0)
134 
135 #define IT66121_INT_MASK1_REG			0x09
136 #define IT66121_INT_MASK1_AUD_OVF		BIT(7)
137 #define IT66121_INT_MASK1_DDC_NOACK		BIT(5)
138 #define IT66121_INT_MASK1_DDC_FIFOERR		BIT(4)
139 #define IT66121_INT_MASK1_DDC_BUSHANG		BIT(2)
140 #define IT66121_INT_MASK1_RX_SENS		BIT(1)
141 #define IT66121_INT_MASK1_HPD			BIT(0)
142 
143 #define IT66121_INT_CLR1_REG			0x0C
144 #define IT66121_INT_CLR1_PKTACP			BIT(7)
145 #define IT66121_INT_CLR1_PKTNULL		BIT(6)
146 #define IT66121_INT_CLR1_PKTGEN			BIT(5)
147 #define IT66121_INT_CLR1_KSVLISTCHK		BIT(4)
148 #define IT66121_INT_CLR1_AUTHDONE		BIT(3)
149 #define IT66121_INT_CLR1_AUTHFAIL		BIT(2)
150 #define IT66121_INT_CLR1_RX_SENS		BIT(1)
151 #define IT66121_INT_CLR1_HPD			BIT(0)
152 
153 #define IT66121_AV_MUTE_REG			0xC1
154 #define IT66121_AV_MUTE_ON			BIT(0)
155 #define IT66121_AV_MUTE_BLUESCR			BIT(1)
156 
157 #define IT66121_PKT_CTS_CTRL_REG		0xC5
158 #define IT66121_PKT_CTS_CTRL_SEL		BIT(1)
159 
160 #define IT66121_PKT_GEN_CTRL_REG		0xC6
161 #define IT66121_PKT_GEN_CTRL_ON			BIT(0)
162 #define IT66121_PKT_GEN_CTRL_RPT		BIT(1)
163 
164 #define IT66121_AVIINFO_DB1_REG			0x158
165 #define IT66121_AVIINFO_DB2_REG			0x159
166 #define IT66121_AVIINFO_DB3_REG			0x15A
167 #define IT66121_AVIINFO_DB4_REG			0x15B
168 #define IT66121_AVIINFO_DB5_REG			0x15C
169 #define IT66121_AVIINFO_CSUM_REG		0x15D
170 #define IT66121_AVIINFO_DB6_REG			0x15E
171 #define IT66121_AVIINFO_DB7_REG			0x15F
172 #define IT66121_AVIINFO_DB8_REG			0x160
173 #define IT66121_AVIINFO_DB9_REG			0x161
174 #define IT66121_AVIINFO_DB10_REG		0x162
175 #define IT66121_AVIINFO_DB11_REG		0x163
176 #define IT66121_AVIINFO_DB12_REG		0x164
177 #define IT66121_AVIINFO_DB13_REG		0x165
178 
179 #define IT66121_AVI_INFO_PKT_REG		0xCD
180 #define IT66121_AVI_INFO_PKT_ON			BIT(0)
181 #define IT66121_AVI_INFO_PKT_RPT		BIT(1)
182 
183 #define IT66121_HDMI_MODE_REG			0xC0
184 #define IT66121_HDMI_MODE_HDMI			BIT(0)
185 
186 #define IT66121_SYS_STATUS_REG			0x0E
187 #define IT66121_SYS_STATUS_ACTIVE_IRQ		BIT(7)
188 #define IT66121_SYS_STATUS_HPDETECT		BIT(6)
189 #define IT66121_SYS_STATUS_SENDECTECT		BIT(5)
190 #define IT66121_SYS_STATUS_VID_STABLE		BIT(4)
191 #define IT66121_SYS_STATUS_AUD_CTS_CLR		BIT(1)
192 #define IT66121_SYS_STATUS_CLEAR_IRQ		BIT(0)
193 
194 #define IT66121_DDC_STATUS_REG			0x16
195 #define IT66121_DDC_STATUS_TX_DONE		BIT(7)
196 #define IT66121_DDC_STATUS_ACTIVE		BIT(6)
197 #define IT66121_DDC_STATUS_NOACK		BIT(5)
198 #define IT66121_DDC_STATUS_WAIT_BUS		BIT(4)
199 #define IT66121_DDC_STATUS_ARBI_LOSE		BIT(3)
200 #define IT66121_DDC_STATUS_FIFO_FULL		BIT(2)
201 #define IT66121_DDC_STATUS_FIFO_EMPTY		BIT(1)
202 #define IT66121_DDC_STATUS_FIFO_VALID		BIT(0)
203 
204 #define IT66121_EDID_SLEEP_US			20000
205 #define IT66121_EDID_TIMEOUT_US			200000
206 #define IT66121_EDID_FIFO_SIZE			32
207 
208 #define IT66121_CLK_CTRL0_REG			0x58
209 #define IT66121_CLK_CTRL0_AUTO_OVER_SAMPLING	BIT(4)
210 #define IT66121_CLK_CTRL0_EXT_MCLK_MASK		GENMASK(3, 2)
211 #define IT66121_CLK_CTRL0_EXT_MCLK_128FS	(0 << 2)
212 #define IT66121_CLK_CTRL0_EXT_MCLK_256FS	BIT(2)
213 #define IT66121_CLK_CTRL0_EXT_MCLK_512FS	(2 << 2)
214 #define IT66121_CLK_CTRL0_EXT_MCLK_1024FS	(3 << 2)
215 #define IT66121_CLK_CTRL0_AUTO_IPCLK		BIT(0)
216 #define IT66121_CLK_STATUS1_REG			0x5E
217 #define IT66121_CLK_STATUS2_REG			0x5F
218 
219 #define IT66121_AUD_CTRL0_REG			0xE0
220 #define IT66121_AUD_SWL				(3 << 6)
221 #define IT66121_AUD_16BIT			(0 << 6)
222 #define IT66121_AUD_18BIT			BIT(6)
223 #define IT66121_AUD_20BIT			(2 << 6)
224 #define IT66121_AUD_24BIT			(3 << 6)
225 #define IT66121_AUD_SPDIFTC			BIT(5)
226 #define IT66121_AUD_SPDIF			BIT(4)
227 #define IT66121_AUD_I2S				(0 << 4)
228 #define IT66121_AUD_EN_I2S3			BIT(3)
229 #define IT66121_AUD_EN_I2S2			BIT(2)
230 #define IT66121_AUD_EN_I2S1			BIT(1)
231 #define IT66121_AUD_EN_I2S0			BIT(0)
232 #define IT66121_AUD_CTRL0_AUD_SEL		BIT(4)
233 
234 #define IT66121_AUD_CTRL1_REG			0xE1
235 #define IT66121_AUD_FIFOMAP_REG			0xE2
236 #define IT66121_AUD_CTRL3_REG			0xE3
237 #define IT66121_AUD_SRCVALID_FLAT_REG		0xE4
238 #define IT66121_AUD_FLAT_SRC0			BIT(4)
239 #define IT66121_AUD_FLAT_SRC1			BIT(5)
240 #define IT66121_AUD_FLAT_SRC2			BIT(6)
241 #define IT66121_AUD_FLAT_SRC3			BIT(7)
242 #define IT66121_AUD_HDAUDIO_REG			0xE5
243 
244 #define IT66121_AUD_PKT_CTS0_REG		0x130
245 #define IT66121_AUD_PKT_CTS1_REG		0x131
246 #define IT66121_AUD_PKT_CTS2_REG		0x132
247 #define IT66121_AUD_PKT_N0_REG			0x133
248 #define IT66121_AUD_PKT_N1_REG			0x134
249 #define IT66121_AUD_PKT_N2_REG			0x135
250 
251 #define IT66121_AUD_CHST_MODE_REG		0x191
252 #define IT66121_AUD_CHST_CAT_REG		0x192
253 #define IT66121_AUD_CHST_SRCNUM_REG		0x193
254 #define IT66121_AUD_CHST_CHTNUM_REG		0x194
255 #define IT66121_AUD_CHST_CA_FS_REG		0x198
256 #define IT66121_AUD_CHST_OFS_WL_REG		0x199
257 
258 #define IT66121_AUD_PKT_CTS_CNT0_REG		0x1A0
259 #define IT66121_AUD_PKT_CTS_CNT1_REG		0x1A1
260 #define IT66121_AUD_PKT_CTS_CNT2_REG		0x1A2
261 
262 #define IT66121_AUD_FS_22P05K			0x4
263 #define IT66121_AUD_FS_44P1K			0x0
264 #define IT66121_AUD_FS_88P2K			0x8
265 #define IT66121_AUD_FS_176P4K			0xC
266 #define IT66121_AUD_FS_24K			0x6
267 #define IT66121_AUD_FS_48K			0x2
268 #define IT66121_AUD_FS_96K			0xA
269 #define IT66121_AUD_FS_192K			0xE
270 #define IT66121_AUD_FS_768K			0x9
271 #define IT66121_AUD_FS_32K			0x3
272 #define IT66121_AUD_FS_OTHER			0x1
273 
274 #define IT66121_AUD_SWL_21BIT			0xD
275 #define IT66121_AUD_SWL_24BIT			0xB
276 #define IT66121_AUD_SWL_23BIT			0x9
277 #define IT66121_AUD_SWL_22BIT			0x5
278 #define IT66121_AUD_SWL_20BIT			0x3
279 #define IT66121_AUD_SWL_17BIT			0xC
280 #define IT66121_AUD_SWL_19BIT			0x8
281 #define IT66121_AUD_SWL_18BIT			0x4
282 #define IT66121_AUD_SWL_16BIT			0x2
283 #define IT66121_AUD_SWL_NOT_INDICATED		0x0
284 
285 #define IT66121_AFE_CLK_HIGH			80000 /* Khz */
286 
287 enum chip_id {
288 	ID_IT6610,
289 	ID_IT66121,
290 };
291 
292 struct it66121_chip_info {
293 	enum chip_id id;
294 	u16 vid, pid;
295 };
296 
297 struct it66121_ctx {
298 	struct regmap *regmap;
299 	struct drm_bridge bridge;
300 	struct drm_bridge *next_bridge;
301 	struct drm_connector *connector;
302 	struct device *dev;
303 	struct gpio_desc *gpio_reset;
304 	struct i2c_client *client;
305 	u32 bus_width;
306 	struct mutex lock; /* Protects fields below and device registers */
307 	struct hdmi_avi_infoframe hdmi_avi_infoframe;
308 	struct {
309 		struct platform_device *pdev;
310 		u8 ch_enable;
311 		u8 fs;
312 		u8 swl;
313 		bool auto_cts;
314 	} audio;
315 	const struct it66121_chip_info *info;
316 };
317 
318 static const struct regmap_range_cfg it66121_regmap_banks[] = {
319 	{
320 		.name = "it66121",
321 		.range_min = 0x00,
322 		.range_max = 0x1FF,
323 		.selector_reg = IT66121_CLK_BANK_REG,
324 		.selector_mask = 0x1,
325 		.selector_shift = 0,
326 		.window_start = 0x00,
327 		.window_len = 0x100,
328 	},
329 };
330 
331 static const struct regmap_config it66121_regmap_config = {
332 	.val_bits = 8,
333 	.reg_bits = 8,
334 	.max_register = 0x1FF,
335 	.ranges = it66121_regmap_banks,
336 	.num_ranges = ARRAY_SIZE(it66121_regmap_banks),
337 };
338 
339 static void it66121_hw_reset(struct it66121_ctx *ctx)
340 {
341 	gpiod_set_value(ctx->gpio_reset, 1);
342 	msleep(20);
343 	gpiod_set_value(ctx->gpio_reset, 0);
344 }
345 
346 static inline int it66121_preamble_ddc(struct it66121_ctx *ctx)
347 {
348 	return regmap_write(ctx->regmap, IT66121_MASTER_SEL_REG, IT66121_MASTER_SEL_HOST);
349 }
350 
351 static inline int it66121_fire_afe(struct it66121_ctx *ctx)
352 {
353 	return regmap_write(ctx->regmap, IT66121_AFE_DRV_REG, 0);
354 }
355 
356 /* TOFIX: Handle YCbCr Input & Output */
357 static int it66121_configure_input(struct it66121_ctx *ctx)
358 {
359 	int ret;
360 	u8 mode = IT66121_INPUT_MODE_RGB;
361 
362 	if (ctx->bus_width == 12)
363 		mode |= IT66121_INPUT_MODE_DDR;
364 
365 	ret = regmap_write(ctx->regmap, IT66121_INPUT_MODE_REG, mode);
366 	if (ret)
367 		return ret;
368 
369 	return regmap_write(ctx->regmap, IT66121_INPUT_CSC_REG, IT66121_INPUT_CSC_NO_CONV);
370 }
371 
372 /**
373  * it66121_configure_afe() - Configure the analog front end
374  * @ctx: it66121_ctx object
375  * @mode: mode to configure
376  *
377  * RETURNS:
378  * zero if success, a negative error code otherwise.
379  */
380 static int it66121_configure_afe(struct it66121_ctx *ctx,
381 				 const struct drm_display_mode *mode)
382 {
383 	int ret;
384 
385 	ret = regmap_write(ctx->regmap, IT66121_AFE_DRV_REG,
386 			   IT66121_AFE_DRV_RST);
387 	if (ret)
388 		return ret;
389 
390 	if (mode->clock > IT66121_AFE_CLK_HIGH) {
391 		ret = regmap_write_bits(ctx->regmap, IT66121_AFE_XP_REG,
392 					IT66121_AFE_XP_GAINBIT |
393 					IT66121_AFE_XP_ENO,
394 					IT66121_AFE_XP_GAINBIT);
395 		if (ret)
396 			return ret;
397 
398 		ret = regmap_write_bits(ctx->regmap, IT66121_AFE_IP_REG,
399 					IT66121_AFE_IP_GAINBIT |
400 					IT66121_AFE_IP_ER0,
401 					IT66121_AFE_IP_GAINBIT);
402 		if (ret)
403 			return ret;
404 
405 		if (ctx->info->id == ID_IT66121) {
406 			ret = regmap_write_bits(ctx->regmap, IT66121_AFE_IP_REG,
407 						IT66121_AFE_IP_EC1, 0);
408 			if (ret)
409 				return ret;
410 
411 			ret = regmap_write_bits(ctx->regmap, IT66121_AFE_XP_EC1_REG,
412 						IT66121_AFE_XP_EC1_LOWCLK, 0x80);
413 			if (ret)
414 				return ret;
415 		}
416 	} else {
417 		ret = regmap_write_bits(ctx->regmap, IT66121_AFE_XP_REG,
418 					IT66121_AFE_XP_GAINBIT |
419 					IT66121_AFE_XP_ENO,
420 					IT66121_AFE_XP_ENO);
421 		if (ret)
422 			return ret;
423 
424 		ret = regmap_write_bits(ctx->regmap, IT66121_AFE_IP_REG,
425 					IT66121_AFE_IP_GAINBIT |
426 					IT66121_AFE_IP_ER0,
427 					IT66121_AFE_IP_ER0);
428 		if (ret)
429 			return ret;
430 
431 		if (ctx->info->id == ID_IT66121) {
432 			ret = regmap_write_bits(ctx->regmap, IT66121_AFE_IP_REG,
433 						IT66121_AFE_IP_EC1,
434 						IT66121_AFE_IP_EC1);
435 			if (ret)
436 				return ret;
437 
438 			ret = regmap_write_bits(ctx->regmap, IT66121_AFE_XP_EC1_REG,
439 						IT66121_AFE_XP_EC1_LOWCLK,
440 						IT66121_AFE_XP_EC1_LOWCLK);
441 			if (ret)
442 				return ret;
443 		}
444 	}
445 
446 	/* Clear reset flags */
447 	ret = regmap_write_bits(ctx->regmap, IT66121_SW_RST_REG,
448 				IT66121_SW_RST_REF | IT66121_SW_RST_VID, 0);
449 	if (ret)
450 		return ret;
451 
452 	if (ctx->info->id == ID_IT6610) {
453 		ret = regmap_write_bits(ctx->regmap, IT66121_AFE_XP_REG,
454 					IT6610_AFE_XP_BYPASS,
455 					IT6610_AFE_XP_BYPASS);
456 		if (ret)
457 			return ret;
458 	}
459 
460 	return it66121_fire_afe(ctx);
461 }
462 
463 static inline int it66121_wait_ddc_ready(struct it66121_ctx *ctx)
464 {
465 	int ret, val;
466 	u32 error = IT66121_DDC_STATUS_NOACK | IT66121_DDC_STATUS_WAIT_BUS |
467 		    IT66121_DDC_STATUS_ARBI_LOSE;
468 	u32 done = IT66121_DDC_STATUS_TX_DONE;
469 
470 	ret = regmap_read_poll_timeout(ctx->regmap, IT66121_DDC_STATUS_REG, val,
471 				       val & (error | done), IT66121_EDID_SLEEP_US,
472 				       IT66121_EDID_TIMEOUT_US);
473 	if (ret)
474 		return ret;
475 
476 	if (val & error)
477 		return -EAGAIN;
478 
479 	return 0;
480 }
481 
482 static int it66121_abort_ddc_ops(struct it66121_ctx *ctx)
483 {
484 	int ret;
485 	unsigned int swreset, cpdesire;
486 
487 	ret = regmap_read(ctx->regmap, IT66121_SW_RST_REG, &swreset);
488 	if (ret)
489 		return ret;
490 
491 	ret = regmap_read(ctx->regmap, IT66121_HDCP_REG, &cpdesire);
492 	if (ret)
493 		return ret;
494 
495 	ret = regmap_write(ctx->regmap, IT66121_HDCP_REG,
496 			   cpdesire & (~IT66121_HDCP_CPDESIRED & 0xFF));
497 	if (ret)
498 		return ret;
499 
500 	ret = regmap_write(ctx->regmap, IT66121_SW_RST_REG,
501 			   (swreset | IT66121_SW_RST_HDCP));
502 	if (ret)
503 		return ret;
504 
505 	ret = it66121_preamble_ddc(ctx);
506 	if (ret)
507 		return ret;
508 
509 	ret = regmap_write(ctx->regmap, IT66121_DDC_COMMAND_REG,
510 			   IT66121_DDC_COMMAND_ABORT);
511 	if (ret)
512 		return ret;
513 
514 	return it66121_wait_ddc_ready(ctx);
515 }
516 
517 static int it66121_get_edid_block(void *context, u8 *buf,
518 				  unsigned int block, size_t len)
519 {
520 	struct it66121_ctx *ctx = context;
521 	int remain = len;
522 	int offset = 0;
523 	int ret, cnt;
524 
525 	offset = (block % 2) * len;
526 	block = block / 2;
527 
528 	while (remain > 0) {
529 		cnt = (remain > IT66121_EDID_FIFO_SIZE) ?
530 				IT66121_EDID_FIFO_SIZE : remain;
531 
532 		ret = regmap_write(ctx->regmap, IT66121_DDC_COMMAND_REG,
533 				   IT66121_DDC_COMMAND_FIFO_CLR);
534 		if (ret)
535 			return ret;
536 
537 		ret = it66121_wait_ddc_ready(ctx);
538 		if (ret)
539 			return ret;
540 
541 		ret = regmap_write(ctx->regmap, IT66121_DDC_OFFSET_REG, offset);
542 		if (ret)
543 			return ret;
544 
545 		ret = regmap_write(ctx->regmap, IT66121_DDC_BYTE_REG, cnt);
546 		if (ret)
547 			return ret;
548 
549 		ret = regmap_write(ctx->regmap, IT66121_DDC_SEGMENT_REG, block);
550 		if (ret)
551 			return ret;
552 
553 		ret = regmap_write(ctx->regmap, IT66121_DDC_COMMAND_REG,
554 				   IT66121_DDC_COMMAND_EDID_READ);
555 		if (ret)
556 			return ret;
557 
558 		offset += cnt;
559 		remain -= cnt;
560 
561 		ret = it66121_wait_ddc_ready(ctx);
562 		if (ret) {
563 			it66121_abort_ddc_ops(ctx);
564 			return ret;
565 		}
566 
567 		ret = regmap_noinc_read(ctx->regmap, IT66121_DDC_RD_FIFO_REG,
568 					buf, cnt);
569 		if (ret)
570 			return ret;
571 
572 		buf += cnt;
573 	}
574 
575 	return 0;
576 }
577 
578 static bool it66121_is_hpd_detect(struct it66121_ctx *ctx)
579 {
580 	int val;
581 
582 	if (regmap_read(ctx->regmap, IT66121_SYS_STATUS_REG, &val))
583 		return false;
584 
585 	return val & IT66121_SYS_STATUS_HPDETECT;
586 }
587 
588 static int it66121_bridge_attach(struct drm_bridge *bridge,
589 				 enum drm_bridge_attach_flags flags)
590 {
591 	struct it66121_ctx *ctx = container_of(bridge, struct it66121_ctx, bridge);
592 	int ret;
593 
594 	if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
595 		return -EINVAL;
596 
597 	ret = drm_bridge_attach(bridge->encoder, ctx->next_bridge, bridge, flags);
598 	if (ret)
599 		return ret;
600 
601 	if (ctx->info->id == ID_IT66121) {
602 		ret = regmap_write_bits(ctx->regmap, IT66121_CLK_BANK_REG,
603 					IT66121_CLK_BANK_PWROFF_RCLK, 0);
604 		if (ret)
605 			return ret;
606 	}
607 
608 	ret = regmap_write_bits(ctx->regmap, IT66121_INT_REG,
609 				IT66121_INT_TX_CLK_OFF, 0);
610 	if (ret)
611 		return ret;
612 
613 	ret = regmap_write_bits(ctx->regmap, IT66121_AFE_DRV_REG,
614 				IT66121_AFE_DRV_PWD, 0);
615 	if (ret)
616 		return ret;
617 
618 	ret = regmap_write_bits(ctx->regmap, IT66121_AFE_XP_REG,
619 				IT66121_AFE_XP_PWDI | IT66121_AFE_XP_PWDPLL, 0);
620 	if (ret)
621 		return ret;
622 
623 	ret = regmap_write_bits(ctx->regmap, IT66121_AFE_IP_REG,
624 				IT66121_AFE_IP_PWDPLL, 0);
625 	if (ret)
626 		return ret;
627 
628 	ret = regmap_write_bits(ctx->regmap, IT66121_AFE_DRV_REG,
629 				IT66121_AFE_DRV_RST, 0);
630 	if (ret)
631 		return ret;
632 
633 	ret = regmap_write_bits(ctx->regmap, IT66121_AFE_XP_REG,
634 				IT66121_AFE_XP_RESETB, IT66121_AFE_XP_RESETB);
635 	if (ret)
636 		return ret;
637 
638 	ret = regmap_write_bits(ctx->regmap, IT66121_AFE_IP_REG,
639 				IT66121_AFE_IP_RESETB, IT66121_AFE_IP_RESETB);
640 	if (ret)
641 		return ret;
642 
643 	ret = regmap_write_bits(ctx->regmap, IT66121_SW_RST_REG,
644 				IT66121_SW_RST_REF,
645 				IT66121_SW_RST_REF);
646 	if (ret)
647 		return ret;
648 
649 	/* Per programming manual, sleep here for bridge to settle */
650 	msleep(50);
651 
652 	return 0;
653 }
654 
655 static int it66121_set_mute(struct it66121_ctx *ctx, bool mute)
656 {
657 	int ret;
658 	unsigned int val = 0;
659 
660 	if (mute)
661 		val = IT66121_AV_MUTE_ON;
662 
663 	ret = regmap_write_bits(ctx->regmap, IT66121_AV_MUTE_REG, IT66121_AV_MUTE_ON, val);
664 	if (ret)
665 		return ret;
666 
667 	return regmap_write(ctx->regmap, IT66121_PKT_GEN_CTRL_REG,
668 			    IT66121_PKT_GEN_CTRL_ON | IT66121_PKT_GEN_CTRL_RPT);
669 }
670 
671 #define MAX_OUTPUT_SEL_FORMATS	1
672 
673 static u32 *it66121_bridge_atomic_get_output_bus_fmts(struct drm_bridge *bridge,
674 						      struct drm_bridge_state *bridge_state,
675 						      struct drm_crtc_state *crtc_state,
676 						      struct drm_connector_state *conn_state,
677 						      unsigned int *num_output_fmts)
678 {
679 	u32 *output_fmts;
680 
681 	output_fmts = kcalloc(MAX_OUTPUT_SEL_FORMATS, sizeof(*output_fmts),
682 			      GFP_KERNEL);
683 	if (!output_fmts)
684 		return NULL;
685 
686 	/* TOFIX handle more than MEDIA_BUS_FMT_RGB888_1X24 as output format */
687 	output_fmts[0] =  MEDIA_BUS_FMT_RGB888_1X24;
688 	*num_output_fmts = 1;
689 
690 	return output_fmts;
691 }
692 
693 #define MAX_INPUT_SEL_FORMATS	1
694 
695 static u32 *it66121_bridge_atomic_get_input_bus_fmts(struct drm_bridge *bridge,
696 						     struct drm_bridge_state *bridge_state,
697 						     struct drm_crtc_state *crtc_state,
698 						     struct drm_connector_state *conn_state,
699 						     u32 output_fmt,
700 						     unsigned int *num_input_fmts)
701 {
702 	struct it66121_ctx *ctx = container_of(bridge, struct it66121_ctx, bridge);
703 	u32 *input_fmts;
704 
705 	*num_input_fmts = 0;
706 
707 	input_fmts = kcalloc(MAX_INPUT_SEL_FORMATS, sizeof(*input_fmts),
708 			     GFP_KERNEL);
709 	if (!input_fmts)
710 		return NULL;
711 
712 	if (ctx->bus_width == 12)
713 		/* IT66121FN Datasheet specifies Little-Endian ordering */
714 		input_fmts[0] = MEDIA_BUS_FMT_RGB888_2X12_LE;
715 	else
716 		/* TOFIX support more input bus formats in 24bit width */
717 		input_fmts[0] = MEDIA_BUS_FMT_RGB888_1X24;
718 	*num_input_fmts = 1;
719 
720 	return input_fmts;
721 }
722 
723 static void it66121_bridge_enable(struct drm_bridge *bridge,
724 				  struct drm_bridge_state *bridge_state)
725 {
726 	struct it66121_ctx *ctx = container_of(bridge, struct it66121_ctx, bridge);
727 	struct drm_atomic_state *state = bridge_state->base.state;
728 
729 	ctx->connector = drm_atomic_get_new_connector_for_encoder(state, bridge->encoder);
730 
731 	it66121_set_mute(ctx, false);
732 }
733 
734 static void it66121_bridge_disable(struct drm_bridge *bridge,
735 				   struct drm_bridge_state *bridge_state)
736 {
737 	struct it66121_ctx *ctx = container_of(bridge, struct it66121_ctx, bridge);
738 
739 	it66121_set_mute(ctx, true);
740 
741 	ctx->connector = NULL;
742 }
743 
744 static int it66121_bridge_check(struct drm_bridge *bridge,
745 				struct drm_bridge_state *bridge_state,
746 				struct drm_crtc_state *crtc_state,
747 				struct drm_connector_state *conn_state)
748 {
749 	struct it66121_ctx *ctx = container_of(bridge, struct it66121_ctx, bridge);
750 
751 	if (ctx->info->id == ID_IT6610) {
752 		/* The IT6610 only supports these settings */
753 		bridge_state->input_bus_cfg.flags |= DRM_BUS_FLAG_DE_HIGH |
754 			DRM_BUS_FLAG_PIXDATA_DRIVE_NEGEDGE;
755 		bridge_state->input_bus_cfg.flags &=
756 			~DRM_BUS_FLAG_PIXDATA_DRIVE_POSEDGE;
757 	}
758 
759 	return 0;
760 }
761 
762 static
763 void it66121_bridge_mode_set(struct drm_bridge *bridge,
764 			     const struct drm_display_mode *mode,
765 			     const struct drm_display_mode *adjusted_mode)
766 {
767 	u8 buf[HDMI_INFOFRAME_SIZE(AVI)];
768 	struct it66121_ctx *ctx = container_of(bridge, struct it66121_ctx, bridge);
769 	int ret;
770 
771 	mutex_lock(&ctx->lock);
772 
773 	hdmi_avi_infoframe_init(&ctx->hdmi_avi_infoframe);
774 
775 	ret = drm_hdmi_avi_infoframe_from_display_mode(&ctx->hdmi_avi_infoframe, ctx->connector,
776 						       adjusted_mode);
777 	if (ret) {
778 		DRM_ERROR("Failed to setup AVI infoframe: %d\n", ret);
779 		goto unlock;
780 	}
781 
782 	ret = hdmi_avi_infoframe_pack(&ctx->hdmi_avi_infoframe, buf, sizeof(buf));
783 	if (ret < 0) {
784 		DRM_ERROR("Failed to pack infoframe: %d\n", ret);
785 		goto unlock;
786 	}
787 
788 	/* Write new AVI infoframe packet */
789 	ret = regmap_bulk_write(ctx->regmap, IT66121_AVIINFO_DB1_REG,
790 				&buf[HDMI_INFOFRAME_HEADER_SIZE],
791 				HDMI_AVI_INFOFRAME_SIZE);
792 	if (ret)
793 		goto unlock;
794 
795 	if (regmap_write(ctx->regmap, IT66121_AVIINFO_CSUM_REG, buf[3]))
796 		goto unlock;
797 
798 	/* Enable AVI infoframe */
799 	if (regmap_write(ctx->regmap, IT66121_AVI_INFO_PKT_REG,
800 			 IT66121_AVI_INFO_PKT_ON | IT66121_AVI_INFO_PKT_RPT))
801 		goto unlock;
802 
803 	/* Set TX mode to HDMI */
804 	if (regmap_write(ctx->regmap, IT66121_HDMI_MODE_REG, IT66121_HDMI_MODE_HDMI))
805 		goto unlock;
806 
807 	if (ctx->info->id == ID_IT66121 &&
808 	    regmap_write_bits(ctx->regmap, IT66121_CLK_BANK_REG,
809 			      IT66121_CLK_BANK_PWROFF_TXCLK,
810 			      IT66121_CLK_BANK_PWROFF_TXCLK)) {
811 		goto unlock;
812 	}
813 
814 	if (it66121_configure_input(ctx))
815 		goto unlock;
816 
817 	if (it66121_configure_afe(ctx, adjusted_mode))
818 		goto unlock;
819 
820 	if (ctx->info->id == ID_IT66121 &&
821 	    regmap_write_bits(ctx->regmap, IT66121_CLK_BANK_REG,
822 			      IT66121_CLK_BANK_PWROFF_TXCLK, 0)) {
823 		goto unlock;
824 	}
825 
826 unlock:
827 	mutex_unlock(&ctx->lock);
828 }
829 
830 static enum drm_mode_status it66121_bridge_mode_valid(struct drm_bridge *bridge,
831 						      const struct drm_display_info *info,
832 						      const struct drm_display_mode *mode)
833 {
834 	struct it66121_ctx *ctx = container_of(bridge, struct it66121_ctx, bridge);
835 	unsigned long max_clock;
836 
837 	max_clock = (ctx->bus_width == 12) ? 74250 : 148500;
838 
839 	if (mode->clock > max_clock)
840 		return MODE_CLOCK_HIGH;
841 
842 	if (mode->clock < 25000)
843 		return MODE_CLOCK_LOW;
844 
845 	return MODE_OK;
846 }
847 
848 static enum drm_connector_status it66121_bridge_detect(struct drm_bridge *bridge)
849 {
850 	struct it66121_ctx *ctx = container_of(bridge, struct it66121_ctx, bridge);
851 
852 	return it66121_is_hpd_detect(ctx) ? connector_status_connected
853 					  : connector_status_disconnected;
854 }
855 
856 static void it66121_bridge_hpd_enable(struct drm_bridge *bridge)
857 {
858 	struct it66121_ctx *ctx = container_of(bridge, struct it66121_ctx, bridge);
859 	int ret;
860 
861 	ret = regmap_write_bits(ctx->regmap, IT66121_INT_MASK1_REG, IT66121_INT_MASK1_HPD, 0);
862 	if (ret)
863 		dev_err(ctx->dev, "failed to enable HPD IRQ\n");
864 }
865 
866 static void it66121_bridge_hpd_disable(struct drm_bridge *bridge)
867 {
868 	struct it66121_ctx *ctx = container_of(bridge, struct it66121_ctx, bridge);
869 	int ret;
870 
871 	ret = regmap_write_bits(ctx->regmap, IT66121_INT_MASK1_REG,
872 				IT66121_INT_MASK1_HPD, IT66121_INT_MASK1_HPD);
873 	if (ret)
874 		dev_err(ctx->dev, "failed to disable HPD IRQ\n");
875 }
876 
877 static struct edid *it66121_bridge_get_edid(struct drm_bridge *bridge,
878 					    struct drm_connector *connector)
879 {
880 	struct it66121_ctx *ctx = container_of(bridge, struct it66121_ctx, bridge);
881 	struct edid *edid;
882 	int ret;
883 
884 	mutex_lock(&ctx->lock);
885 	ret = it66121_preamble_ddc(ctx);
886 	if (ret) {
887 		edid = NULL;
888 		goto out_unlock;
889 	}
890 
891 	ret = regmap_write(ctx->regmap, IT66121_DDC_HEADER_REG,
892 			   IT66121_DDC_HEADER_EDID);
893 	if (ret) {
894 		edid = NULL;
895 		goto out_unlock;
896 	}
897 
898 	edid = drm_do_get_edid(connector, it66121_get_edid_block, ctx);
899 
900 out_unlock:
901 	mutex_unlock(&ctx->lock);
902 
903 	return edid;
904 }
905 
906 static const struct drm_bridge_funcs it66121_bridge_funcs = {
907 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
908 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
909 	.atomic_reset = drm_atomic_helper_bridge_reset,
910 	.attach = it66121_bridge_attach,
911 	.atomic_get_output_bus_fmts = it66121_bridge_atomic_get_output_bus_fmts,
912 	.atomic_get_input_bus_fmts = it66121_bridge_atomic_get_input_bus_fmts,
913 	.atomic_enable = it66121_bridge_enable,
914 	.atomic_disable = it66121_bridge_disable,
915 	.atomic_check = it66121_bridge_check,
916 	.mode_set = it66121_bridge_mode_set,
917 	.mode_valid = it66121_bridge_mode_valid,
918 	.detect = it66121_bridge_detect,
919 	.get_edid = it66121_bridge_get_edid,
920 	.hpd_enable = it66121_bridge_hpd_enable,
921 	.hpd_disable = it66121_bridge_hpd_disable,
922 };
923 
924 static irqreturn_t it66121_irq_threaded_handler(int irq, void *dev_id)
925 {
926 	int ret;
927 	unsigned int val;
928 	struct it66121_ctx *ctx = dev_id;
929 	struct device *dev = ctx->dev;
930 	enum drm_connector_status status;
931 	bool event = false;
932 
933 	mutex_lock(&ctx->lock);
934 
935 	ret = regmap_read(ctx->regmap, IT66121_SYS_STATUS_REG, &val);
936 	if (ret)
937 		goto unlock;
938 
939 	if (!(val & IT66121_SYS_STATUS_ACTIVE_IRQ))
940 		goto unlock;
941 
942 	ret = regmap_read(ctx->regmap, IT66121_INT_STATUS1_REG, &val);
943 	if (ret) {
944 		dev_err(dev, "Cannot read STATUS1_REG %d\n", ret);
945 	} else if (val & IT66121_INT_STATUS1_HPD_STATUS) {
946 		regmap_write_bits(ctx->regmap, IT66121_INT_CLR1_REG,
947 				  IT66121_INT_CLR1_HPD, IT66121_INT_CLR1_HPD);
948 
949 		status = it66121_is_hpd_detect(ctx) ? connector_status_connected
950 			: connector_status_disconnected;
951 
952 		event = true;
953 	}
954 
955 	regmap_write_bits(ctx->regmap, IT66121_SYS_STATUS_REG,
956 			  IT66121_SYS_STATUS_CLEAR_IRQ,
957 			  IT66121_SYS_STATUS_CLEAR_IRQ);
958 
959 unlock:
960 	mutex_unlock(&ctx->lock);
961 
962 	if (event)
963 		drm_bridge_hpd_notify(&ctx->bridge, status);
964 
965 	return IRQ_HANDLED;
966 }
967 
968 static int it661221_set_chstat(struct it66121_ctx *ctx, u8 iec60958_chstat[])
969 {
970 	int ret;
971 
972 	ret = regmap_write(ctx->regmap, IT66121_AUD_CHST_MODE_REG, iec60958_chstat[0] & 0x7C);
973 	if (ret)
974 		return ret;
975 
976 	ret = regmap_write(ctx->regmap, IT66121_AUD_CHST_CAT_REG, iec60958_chstat[1]);
977 	if (ret)
978 		return ret;
979 
980 	ret = regmap_write(ctx->regmap, IT66121_AUD_CHST_SRCNUM_REG, iec60958_chstat[2] & 0x0F);
981 	if (ret)
982 		return ret;
983 
984 	ret = regmap_write(ctx->regmap, IT66121_AUD_CHST_CHTNUM_REG,
985 			   (iec60958_chstat[2] >> 4) & 0x0F);
986 	if (ret)
987 		return ret;
988 
989 	ret = regmap_write(ctx->regmap, IT66121_AUD_CHST_CA_FS_REG, iec60958_chstat[3]);
990 	if (ret)
991 		return ret;
992 
993 	return regmap_write(ctx->regmap, IT66121_AUD_CHST_OFS_WL_REG, iec60958_chstat[4]);
994 }
995 
996 static int it661221_set_lpcm_audio(struct it66121_ctx *ctx, u8 audio_src_num, u8 audio_swl)
997 {
998 	int ret;
999 	unsigned int audio_enable = 0;
1000 	unsigned int audio_format = 0;
1001 
1002 	switch (audio_swl) {
1003 	case 16:
1004 		audio_enable |= IT66121_AUD_16BIT;
1005 		break;
1006 	case 18:
1007 		audio_enable |= IT66121_AUD_18BIT;
1008 		break;
1009 	case 20:
1010 		audio_enable |= IT66121_AUD_20BIT;
1011 		break;
1012 	case 24:
1013 	default:
1014 		audio_enable |= IT66121_AUD_24BIT;
1015 		break;
1016 	}
1017 
1018 	audio_format |= 0x40;
1019 	switch (audio_src_num) {
1020 	case 4:
1021 		audio_enable |= IT66121_AUD_EN_I2S3 | IT66121_AUD_EN_I2S2 |
1022 				IT66121_AUD_EN_I2S1 | IT66121_AUD_EN_I2S0;
1023 		break;
1024 	case 3:
1025 		audio_enable |= IT66121_AUD_EN_I2S2 | IT66121_AUD_EN_I2S1 |
1026 				IT66121_AUD_EN_I2S0;
1027 		break;
1028 	case 2:
1029 		audio_enable |= IT66121_AUD_EN_I2S1 | IT66121_AUD_EN_I2S0;
1030 		break;
1031 	case 1:
1032 	default:
1033 		audio_format &= ~0x40;
1034 		audio_enable |= IT66121_AUD_EN_I2S0;
1035 		break;
1036 	}
1037 
1038 	audio_format |= 0x01;
1039 	ctx->audio.ch_enable = audio_enable;
1040 
1041 	ret = regmap_write(ctx->regmap, IT66121_AUD_CTRL0_REG, audio_enable & 0xF0);
1042 	if (ret)
1043 		return ret;
1044 
1045 	ret = regmap_write(ctx->regmap, IT66121_AUD_CTRL1_REG, audio_format);
1046 	if (ret)
1047 		return ret;
1048 
1049 	ret = regmap_write(ctx->regmap, IT66121_AUD_FIFOMAP_REG, 0xE4);
1050 	if (ret)
1051 		return ret;
1052 
1053 	ret = regmap_write(ctx->regmap, IT66121_AUD_CTRL3_REG, 0x00);
1054 	if (ret)
1055 		return ret;
1056 
1057 	ret = regmap_write(ctx->regmap, IT66121_AUD_SRCVALID_FLAT_REG, 0x00);
1058 	if (ret)
1059 		return ret;
1060 
1061 	return regmap_write(ctx->regmap, IT66121_AUD_HDAUDIO_REG, 0x00);
1062 }
1063 
1064 static int it661221_set_ncts(struct it66121_ctx *ctx, u8 fs)
1065 {
1066 	int ret;
1067 	unsigned int n;
1068 
1069 	switch (fs) {
1070 	case IT66121_AUD_FS_32K:
1071 		n = 4096;
1072 		break;
1073 	case IT66121_AUD_FS_44P1K:
1074 		n = 6272;
1075 		break;
1076 	case IT66121_AUD_FS_48K:
1077 		n = 6144;
1078 		break;
1079 	case IT66121_AUD_FS_88P2K:
1080 		n = 12544;
1081 		break;
1082 	case IT66121_AUD_FS_96K:
1083 		n = 12288;
1084 		break;
1085 	case IT66121_AUD_FS_176P4K:
1086 		n = 25088;
1087 		break;
1088 	case IT66121_AUD_FS_192K:
1089 		n = 24576;
1090 		break;
1091 	case IT66121_AUD_FS_768K:
1092 		n = 24576;
1093 		break;
1094 	default:
1095 		n = 6144;
1096 		break;
1097 	}
1098 
1099 	ret = regmap_write(ctx->regmap, IT66121_AUD_PKT_N0_REG, (u8)((n) & 0xFF));
1100 	if (ret)
1101 		return ret;
1102 
1103 	ret = regmap_write(ctx->regmap, IT66121_AUD_PKT_N1_REG, (u8)((n >> 8) & 0xFF));
1104 	if (ret)
1105 		return ret;
1106 
1107 	ret = regmap_write(ctx->regmap, IT66121_AUD_PKT_N2_REG, (u8)((n >> 16) & 0xF));
1108 	if (ret)
1109 		return ret;
1110 
1111 	if (ctx->audio.auto_cts) {
1112 		u8 loop_cnt = 255;
1113 		u8 cts_stable_cnt = 0;
1114 		unsigned int sum_cts = 0;
1115 		unsigned int cts = 0;
1116 		unsigned int last_cts = 0;
1117 		unsigned int diff;
1118 		unsigned int val;
1119 
1120 		while (loop_cnt--) {
1121 			msleep(30);
1122 			regmap_read(ctx->regmap, IT66121_AUD_PKT_CTS_CNT2_REG, &val);
1123 			cts = val << 12;
1124 			regmap_read(ctx->regmap, IT66121_AUD_PKT_CTS_CNT1_REG, &val);
1125 			cts |= val << 4;
1126 			regmap_read(ctx->regmap, IT66121_AUD_PKT_CTS_CNT0_REG, &val);
1127 			cts |= val >> 4;
1128 			if (cts == 0) {
1129 				continue;
1130 			} else {
1131 				if (last_cts > cts)
1132 					diff = last_cts - cts;
1133 				else
1134 					diff = cts - last_cts;
1135 				last_cts = cts;
1136 				if (diff < 5) {
1137 					cts_stable_cnt++;
1138 					sum_cts += cts;
1139 				} else {
1140 					cts_stable_cnt = 0;
1141 					sum_cts = 0;
1142 					continue;
1143 				}
1144 
1145 				if (cts_stable_cnt >= 32) {
1146 					last_cts = (sum_cts >> 5);
1147 					break;
1148 				}
1149 			}
1150 		}
1151 
1152 		regmap_write(ctx->regmap, IT66121_AUD_PKT_CTS0_REG, (u8)((last_cts) & 0xFF));
1153 		regmap_write(ctx->regmap, IT66121_AUD_PKT_CTS1_REG, (u8)((last_cts >> 8) & 0xFF));
1154 		regmap_write(ctx->regmap, IT66121_AUD_PKT_CTS2_REG, (u8)((last_cts >> 16) & 0x0F));
1155 	}
1156 
1157 	ret = regmap_write(ctx->regmap, 0xF8, 0xC3);
1158 	if (ret)
1159 		return ret;
1160 
1161 	ret = regmap_write(ctx->regmap, 0xF8, 0xA5);
1162 	if (ret)
1163 		return ret;
1164 
1165 	if (ctx->audio.auto_cts) {
1166 		ret = regmap_write_bits(ctx->regmap, IT66121_PKT_CTS_CTRL_REG,
1167 					IT66121_PKT_CTS_CTRL_SEL,
1168 					1);
1169 	} else {
1170 		ret = regmap_write_bits(ctx->regmap, IT66121_PKT_CTS_CTRL_REG,
1171 					IT66121_PKT_CTS_CTRL_SEL,
1172 					0);
1173 	}
1174 
1175 	if (ret)
1176 		return ret;
1177 
1178 	return regmap_write(ctx->regmap, 0xF8, 0xFF);
1179 }
1180 
1181 static int it661221_audio_output_enable(struct it66121_ctx *ctx, bool enable)
1182 {
1183 	int ret;
1184 
1185 	if (enable) {
1186 		ret = regmap_write_bits(ctx->regmap, IT66121_SW_RST_REG,
1187 					IT66121_SW_RST_AUD | IT66121_SW_RST_AREF,
1188 					0);
1189 		if (ret)
1190 			return ret;
1191 
1192 		ret = regmap_write_bits(ctx->regmap, IT66121_AUD_CTRL0_REG,
1193 					IT66121_AUD_EN_I2S3 | IT66121_AUD_EN_I2S2 |
1194 					IT66121_AUD_EN_I2S1 | IT66121_AUD_EN_I2S0,
1195 					ctx->audio.ch_enable);
1196 	} else {
1197 		ret = regmap_write_bits(ctx->regmap, IT66121_AUD_CTRL0_REG,
1198 					IT66121_AUD_EN_I2S3 | IT66121_AUD_EN_I2S2 |
1199 					IT66121_AUD_EN_I2S1 | IT66121_AUD_EN_I2S0,
1200 					ctx->audio.ch_enable & 0xF0);
1201 		if (ret)
1202 			return ret;
1203 
1204 		ret = regmap_write_bits(ctx->regmap, IT66121_SW_RST_REG,
1205 					IT66121_SW_RST_AUD | IT66121_SW_RST_AREF,
1206 					IT66121_SW_RST_AUD | IT66121_SW_RST_AREF);
1207 	}
1208 
1209 	return ret;
1210 }
1211 
1212 static int it661221_audio_ch_enable(struct it66121_ctx *ctx, bool enable)
1213 {
1214 	int ret;
1215 
1216 	if (enable) {
1217 		ret = regmap_write(ctx->regmap, IT66121_AUD_SRCVALID_FLAT_REG, 0);
1218 		if (ret)
1219 			return ret;
1220 
1221 		ret = regmap_write(ctx->regmap, IT66121_AUD_CTRL0_REG, ctx->audio.ch_enable);
1222 	} else {
1223 		ret = regmap_write(ctx->regmap, IT66121_AUD_CTRL0_REG, ctx->audio.ch_enable & 0xF0);
1224 	}
1225 
1226 	return ret;
1227 }
1228 
1229 static int it66121_audio_hw_params(struct device *dev, void *data,
1230 				   struct hdmi_codec_daifmt *daifmt,
1231 				   struct hdmi_codec_params *params)
1232 {
1233 	u8 fs;
1234 	u8 swl;
1235 	int ret;
1236 	struct it66121_ctx *ctx = dev_get_drvdata(dev);
1237 	static u8 iec60958_chstat[5];
1238 	unsigned int channels = params->channels;
1239 	unsigned int sample_rate = params->sample_rate;
1240 	unsigned int sample_width = params->sample_width;
1241 
1242 	mutex_lock(&ctx->lock);
1243 	dev_dbg(dev, "%s: %u, %u, %u, %u\n", __func__,
1244 		daifmt->fmt, sample_rate, sample_width, channels);
1245 
1246 	switch (daifmt->fmt) {
1247 	case HDMI_I2S:
1248 		dev_dbg(dev, "Using HDMI I2S\n");
1249 		break;
1250 	default:
1251 		dev_err(dev, "Invalid or unsupported DAI format %d\n", daifmt->fmt);
1252 		ret = -EINVAL;
1253 		goto out;
1254 	}
1255 
1256 	// Set audio clock recovery (N/CTS)
1257 	ret = regmap_write(ctx->regmap, IT66121_CLK_CTRL0_REG,
1258 			   IT66121_CLK_CTRL0_AUTO_OVER_SAMPLING |
1259 			   IT66121_CLK_CTRL0_EXT_MCLK_256FS |
1260 			   IT66121_CLK_CTRL0_AUTO_IPCLK);
1261 	if (ret)
1262 		goto out;
1263 
1264 	ret = regmap_write_bits(ctx->regmap, IT66121_AUD_CTRL0_REG,
1265 				IT66121_AUD_CTRL0_AUD_SEL, 0); // remove spdif selection
1266 	if (ret)
1267 		goto out;
1268 
1269 	switch (sample_rate) {
1270 	case 44100L:
1271 		fs = IT66121_AUD_FS_44P1K;
1272 		break;
1273 	case 88200L:
1274 		fs = IT66121_AUD_FS_88P2K;
1275 		break;
1276 	case 176400L:
1277 		fs = IT66121_AUD_FS_176P4K;
1278 		break;
1279 	case 32000L:
1280 		fs = IT66121_AUD_FS_32K;
1281 		break;
1282 	case 48000L:
1283 		fs = IT66121_AUD_FS_48K;
1284 		break;
1285 	case 96000L:
1286 		fs = IT66121_AUD_FS_96K;
1287 		break;
1288 	case 192000L:
1289 		fs = IT66121_AUD_FS_192K;
1290 		break;
1291 	case 768000L:
1292 		fs = IT66121_AUD_FS_768K;
1293 		break;
1294 	default:
1295 		fs = IT66121_AUD_FS_48K;
1296 		break;
1297 	}
1298 
1299 	ctx->audio.fs = fs;
1300 	ret = it661221_set_ncts(ctx, fs);
1301 	if (ret) {
1302 		dev_err(dev, "Failed to set N/CTS: %d\n", ret);
1303 		goto out;
1304 	}
1305 
1306 	// Set audio format register (except audio channel enable)
1307 	ret = it661221_set_lpcm_audio(ctx, (channels + 1) / 2, sample_width);
1308 	if (ret) {
1309 		dev_err(dev, "Failed to set LPCM audio: %d\n", ret);
1310 		goto out;
1311 	}
1312 
1313 	// Set audio channel status
1314 	iec60958_chstat[0] = 0;
1315 	if ((channels + 1) / 2 == 1)
1316 		iec60958_chstat[0] |= 0x1;
1317 	iec60958_chstat[0] &= ~(1 << 1);
1318 	iec60958_chstat[1] = 0;
1319 	iec60958_chstat[2] = (channels + 1) / 2;
1320 	iec60958_chstat[2] |= (channels << 4) & 0xF0;
1321 	iec60958_chstat[3] = fs;
1322 
1323 	switch (sample_width) {
1324 	case 21L:
1325 		swl = IT66121_AUD_SWL_21BIT;
1326 		break;
1327 	case 24L:
1328 		swl = IT66121_AUD_SWL_24BIT;
1329 		break;
1330 	case 23L:
1331 		swl = IT66121_AUD_SWL_23BIT;
1332 		break;
1333 	case 22L:
1334 		swl = IT66121_AUD_SWL_22BIT;
1335 		break;
1336 	case 20L:
1337 		swl = IT66121_AUD_SWL_20BIT;
1338 		break;
1339 	case 17L:
1340 		swl = IT66121_AUD_SWL_17BIT;
1341 		break;
1342 	case 19L:
1343 		swl = IT66121_AUD_SWL_19BIT;
1344 		break;
1345 	case 18L:
1346 		swl = IT66121_AUD_SWL_18BIT;
1347 		break;
1348 	case 16L:
1349 		swl = IT66121_AUD_SWL_16BIT;
1350 		break;
1351 	default:
1352 		swl = IT66121_AUD_SWL_NOT_INDICATED;
1353 		break;
1354 	}
1355 
1356 	iec60958_chstat[4] = (((~fs) << 4) & 0xF0) | swl;
1357 	ret = it661221_set_chstat(ctx, iec60958_chstat);
1358 	if (ret) {
1359 		dev_err(dev, "Failed to set channel status: %d\n", ret);
1360 		goto out;
1361 	}
1362 
1363 	// Enable audio channel enable while input clock stable (if SPDIF).
1364 	ret = it661221_audio_ch_enable(ctx, true);
1365 	if (ret) {
1366 		dev_err(dev, "Failed to enable audio channel: %d\n", ret);
1367 		goto out;
1368 	}
1369 
1370 	ret = regmap_write_bits(ctx->regmap, IT66121_INT_MASK1_REG,
1371 				IT66121_INT_MASK1_AUD_OVF,
1372 				0);
1373 	if (ret)
1374 		goto out;
1375 
1376 	dev_dbg(dev, "HDMI audio enabled.\n");
1377 out:
1378 	mutex_unlock(&ctx->lock);
1379 
1380 	return ret;
1381 }
1382 
1383 static int it66121_audio_startup(struct device *dev, void *data)
1384 {
1385 	int ret;
1386 	struct it66121_ctx *ctx = dev_get_drvdata(dev);
1387 
1388 	dev_dbg(dev, "%s\n", __func__);
1389 
1390 	mutex_lock(&ctx->lock);
1391 	ret = it661221_audio_output_enable(ctx, true);
1392 	if (ret)
1393 		dev_err(dev, "Failed to enable audio output: %d\n", ret);
1394 
1395 	mutex_unlock(&ctx->lock);
1396 
1397 	return ret;
1398 }
1399 
1400 static void it66121_audio_shutdown(struct device *dev, void *data)
1401 {
1402 	int ret;
1403 	struct it66121_ctx *ctx = dev_get_drvdata(dev);
1404 
1405 	dev_dbg(dev, "%s\n", __func__);
1406 
1407 	mutex_lock(&ctx->lock);
1408 	ret = it661221_audio_output_enable(ctx, false);
1409 	if (ret)
1410 		dev_err(dev, "Failed to disable audio output: %d\n", ret);
1411 
1412 	mutex_unlock(&ctx->lock);
1413 }
1414 
1415 static int it66121_audio_mute(struct device *dev, void *data,
1416 			      bool enable, int direction)
1417 {
1418 	int ret;
1419 	struct it66121_ctx *ctx = dev_get_drvdata(dev);
1420 
1421 	dev_dbg(dev, "%s: enable=%s, direction=%d\n",
1422 		__func__, enable ? "true" : "false", direction);
1423 
1424 	mutex_lock(&ctx->lock);
1425 
1426 	if (enable) {
1427 		ret = regmap_write_bits(ctx->regmap, IT66121_AUD_SRCVALID_FLAT_REG,
1428 					IT66121_AUD_FLAT_SRC0 | IT66121_AUD_FLAT_SRC1 |
1429 					IT66121_AUD_FLAT_SRC2 | IT66121_AUD_FLAT_SRC3,
1430 					IT66121_AUD_FLAT_SRC0 | IT66121_AUD_FLAT_SRC1 |
1431 					IT66121_AUD_FLAT_SRC2 | IT66121_AUD_FLAT_SRC3);
1432 	} else {
1433 		ret = regmap_write_bits(ctx->regmap, IT66121_AUD_SRCVALID_FLAT_REG,
1434 					IT66121_AUD_FLAT_SRC0 | IT66121_AUD_FLAT_SRC1 |
1435 					IT66121_AUD_FLAT_SRC2 | IT66121_AUD_FLAT_SRC3,
1436 					0);
1437 	}
1438 
1439 	mutex_unlock(&ctx->lock);
1440 
1441 	return ret;
1442 }
1443 
1444 static int it66121_audio_get_eld(struct device *dev, void *data,
1445 				 u8 *buf, size_t len)
1446 {
1447 	struct it66121_ctx *ctx = dev_get_drvdata(dev);
1448 
1449 	mutex_lock(&ctx->lock);
1450 	if (!ctx->connector) {
1451 		/* Pass en empty ELD if connector not available */
1452 		dev_dbg(dev, "No connector present, passing empty EDID data");
1453 		memset(buf, 0, len);
1454 	} else {
1455 		memcpy(buf, ctx->connector->eld,
1456 		       min(sizeof(ctx->connector->eld), len));
1457 	}
1458 	mutex_unlock(&ctx->lock);
1459 
1460 	return 0;
1461 }
1462 
1463 static const struct hdmi_codec_ops it66121_audio_codec_ops = {
1464 	.hw_params = it66121_audio_hw_params,
1465 	.audio_startup = it66121_audio_startup,
1466 	.audio_shutdown = it66121_audio_shutdown,
1467 	.mute_stream = it66121_audio_mute,
1468 	.get_eld = it66121_audio_get_eld,
1469 	.no_capture_mute = 1,
1470 };
1471 
1472 static int it66121_audio_codec_init(struct it66121_ctx *ctx, struct device *dev)
1473 {
1474 	struct hdmi_codec_pdata codec_data = {
1475 		.ops = &it66121_audio_codec_ops,
1476 		.i2s = 1, /* Only i2s support for now */
1477 		.spdif = 0,
1478 		.max_i2s_channels = 8,
1479 	};
1480 
1481 	dev_dbg(dev, "%s\n", __func__);
1482 
1483 	if (!of_property_read_bool(dev->of_node, "#sound-dai-cells")) {
1484 		dev_info(dev, "No \"#sound-dai-cells\", no audio\n");
1485 		return 0;
1486 	}
1487 
1488 	ctx->audio.pdev = platform_device_register_data(dev,
1489 							HDMI_CODEC_DRV_NAME,
1490 							PLATFORM_DEVID_AUTO,
1491 							&codec_data,
1492 							sizeof(codec_data));
1493 
1494 	if (IS_ERR(ctx->audio.pdev)) {
1495 		dev_err(dev, "Failed to initialize HDMI audio codec: %d\n",
1496 			PTR_ERR_OR_ZERO(ctx->audio.pdev));
1497 	}
1498 
1499 	return PTR_ERR_OR_ZERO(ctx->audio.pdev);
1500 }
1501 
1502 static const char * const it66121_supplies[] = {
1503 	"vcn33", "vcn18", "vrf12"
1504 };
1505 
1506 static int it66121_probe(struct i2c_client *client)
1507 {
1508 	const struct i2c_device_id *id = i2c_client_get_device_id(client);
1509 	u32 revision_id, vendor_ids[2] = { 0 }, device_ids[2] = { 0 };
1510 	struct device_node *ep;
1511 	int ret;
1512 	struct it66121_ctx *ctx;
1513 	struct device *dev = &client->dev;
1514 
1515 	if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
1516 		dev_err(dev, "I2C check functionality failed.\n");
1517 		return -ENXIO;
1518 	}
1519 
1520 	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
1521 	if (!ctx)
1522 		return -ENOMEM;
1523 
1524 	ep = of_graph_get_endpoint_by_regs(dev->of_node, 0, 0);
1525 	if (!ep)
1526 		return -EINVAL;
1527 
1528 	ctx->dev = dev;
1529 	ctx->client = client;
1530 	ctx->info = (const struct it66121_chip_info *) id->driver_data;
1531 
1532 	of_property_read_u32(ep, "bus-width", &ctx->bus_width);
1533 	of_node_put(ep);
1534 
1535 	if (ctx->bus_width != 12 && ctx->bus_width != 24)
1536 		return -EINVAL;
1537 
1538 	ep = of_graph_get_remote_node(dev->of_node, 1, -1);
1539 	if (!ep) {
1540 		dev_err(ctx->dev, "The endpoint is unconnected\n");
1541 		return -EINVAL;
1542 	}
1543 
1544 	if (!of_device_is_available(ep)) {
1545 		of_node_put(ep);
1546 		dev_err(ctx->dev, "The remote device is disabled\n");
1547 		return -ENODEV;
1548 	}
1549 
1550 	ctx->next_bridge = of_drm_find_bridge(ep);
1551 	of_node_put(ep);
1552 	if (!ctx->next_bridge) {
1553 		dev_dbg(ctx->dev, "Next bridge not found, deferring probe\n");
1554 		return -EPROBE_DEFER;
1555 	}
1556 
1557 	i2c_set_clientdata(client, ctx);
1558 	mutex_init(&ctx->lock);
1559 
1560 	ret = devm_regulator_bulk_get_enable(dev, ARRAY_SIZE(it66121_supplies),
1561 					     it66121_supplies);
1562 	if (ret) {
1563 		dev_err(dev, "Failed to enable power supplies\n");
1564 		return ret;
1565 	}
1566 
1567 	it66121_hw_reset(ctx);
1568 
1569 	ctx->regmap = devm_regmap_init_i2c(client, &it66121_regmap_config);
1570 	if (IS_ERR(ctx->regmap))
1571 		return PTR_ERR(ctx->regmap);
1572 
1573 	regmap_read(ctx->regmap, IT66121_VENDOR_ID0_REG, &vendor_ids[0]);
1574 	regmap_read(ctx->regmap, IT66121_VENDOR_ID1_REG, &vendor_ids[1]);
1575 	regmap_read(ctx->regmap, IT66121_DEVICE_ID0_REG, &device_ids[0]);
1576 	regmap_read(ctx->regmap, IT66121_DEVICE_ID1_REG, &device_ids[1]);
1577 
1578 	/* Revision is shared with DEVICE_ID1 */
1579 	revision_id = FIELD_GET(IT66121_REVISION_MASK, device_ids[1]);
1580 	device_ids[1] &= IT66121_DEVICE_ID1_MASK;
1581 
1582 	if ((vendor_ids[1] << 8 | vendor_ids[0]) != ctx->info->vid ||
1583 	    (device_ids[1] << 8 | device_ids[0]) != ctx->info->pid) {
1584 		return -ENODEV;
1585 	}
1586 
1587 	ctx->bridge.funcs = &it66121_bridge_funcs;
1588 	ctx->bridge.of_node = dev->of_node;
1589 	ctx->bridge.type = DRM_MODE_CONNECTOR_HDMIA;
1590 	ctx->bridge.ops = DRM_BRIDGE_OP_DETECT | DRM_BRIDGE_OP_EDID | DRM_BRIDGE_OP_HPD;
1591 
1592 	ret = devm_request_threaded_irq(dev, client->irq, NULL,	it66121_irq_threaded_handler,
1593 					IRQF_ONESHOT, dev_name(dev), ctx);
1594 	if (ret < 0) {
1595 		dev_err(dev, "Failed to request irq %d:%d\n", client->irq, ret);
1596 		return ret;
1597 	}
1598 
1599 	it66121_audio_codec_init(ctx, dev);
1600 
1601 	drm_bridge_add(&ctx->bridge);
1602 
1603 	dev_info(ctx->dev, "IT66121 revision %d probed\n", revision_id);
1604 
1605 	return 0;
1606 }
1607 
1608 static void it66121_remove(struct i2c_client *client)
1609 {
1610 	struct it66121_ctx *ctx = i2c_get_clientdata(client);
1611 
1612 	drm_bridge_remove(&ctx->bridge);
1613 	mutex_destroy(&ctx->lock);
1614 }
1615 
1616 static const struct of_device_id it66121_dt_match[] = {
1617 	{ .compatible = "ite,it66121" },
1618 	{ .compatible = "ite,it6610" },
1619 	{ }
1620 };
1621 MODULE_DEVICE_TABLE(of, it66121_dt_match);
1622 
1623 static const struct it66121_chip_info it66121_chip_info = {
1624 	.id = ID_IT66121,
1625 	.vid = 0x4954,
1626 	.pid = 0x0612,
1627 };
1628 
1629 static const struct it66121_chip_info it6610_chip_info = {
1630 	.id = ID_IT6610,
1631 	.vid = 0xca00,
1632 	.pid = 0x0611,
1633 };
1634 
1635 static const struct i2c_device_id it66121_id[] = {
1636 	{ "it66121", (kernel_ulong_t) &it66121_chip_info },
1637 	{ "it6610", (kernel_ulong_t) &it6610_chip_info },
1638 	{ }
1639 };
1640 MODULE_DEVICE_TABLE(i2c, it66121_id);
1641 
1642 static struct i2c_driver it66121_driver = {
1643 	.driver = {
1644 		.name	= "it66121",
1645 		.of_match_table = it66121_dt_match,
1646 	},
1647 	.probe = it66121_probe,
1648 	.remove = it66121_remove,
1649 	.id_table = it66121_id,
1650 };
1651 
1652 module_i2c_driver(it66121_driver);
1653 
1654 MODULE_AUTHOR("Phong LE");
1655 MODULE_DESCRIPTION("IT66121 HDMI transmitter driver");
1656 MODULE_LICENSE("GPL v2");
1657