xref: /linux/drivers/gpu/drm/bridge/sii9234.c (revision 9e56ff53b4115875667760445b028357848b4748)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2017 Samsung Electronics
4  *
5  * Authors:
6  *    Tomasz Stanislawski <t.stanislaws@samsung.com>
7  *    Maciej Purski <m.purski@samsung.com>
8  *
9  * Based on sii9234 driver created by:
10  *    Adam Hampson <ahampson@sta.samsung.com>
11  *    Erik Gilling <konkers@android.com>
12  *    Shankar Bandal <shankar.b@samsung.com>
13  *    Dharam Kumar <dharam.kr@samsung.com>
14  */
15 #include <drm/bridge/mhl.h>
16 #include <drm/drm_bridge.h>
17 #include <drm/drm_crtc.h>
18 #include <drm/drm_edid.h>
19 
20 #include <linux/delay.h>
21 #include <linux/err.h>
22 #include <linux/gpio/consumer.h>
23 #include <linux/i2c.h>
24 #include <linux/interrupt.h>
25 #include <linux/irq.h>
26 #include <linux/kernel.h>
27 #include <linux/module.h>
28 #include <linux/mutex.h>
29 #include <linux/regulator/consumer.h>
30 #include <linux/slab.h>
31 
32 #define CBUS_DEVCAP_OFFSET		0x80
33 
34 #define SII9234_MHL_VERSION		0x11
35 #define SII9234_SCRATCHPAD_SIZE		0x10
36 #define SII9234_INT_STAT_SIZE		0x33
37 
38 #define BIT_TMDS_CCTRL_TMDS_OE		BIT(4)
39 #define MHL_HPD_OUT_OVR_EN		BIT(4)
40 #define MHL_HPD_OUT_OVR_VAL		BIT(5)
41 #define MHL_INIT_TIMEOUT		0x0C
42 
43 /* MHL Tx registers and bits */
44 #define MHL_TX_SRST			0x05
45 #define MHL_TX_SYSSTAT_REG		0x09
46 #define MHL_TX_INTR1_REG		0x71
47 #define MHL_TX_INTR4_REG		0x74
48 #define MHL_TX_INTR1_ENABLE_REG		0x75
49 #define MHL_TX_INTR4_ENABLE_REG		0x78
50 #define MHL_TX_INT_CTRL_REG		0x79
51 #define MHL_TX_TMDS_CCTRL		0x80
52 #define MHL_TX_DISC_CTRL1_REG		0x90
53 #define MHL_TX_DISC_CTRL2_REG		0x91
54 #define MHL_TX_DISC_CTRL3_REG		0x92
55 #define MHL_TX_DISC_CTRL4_REG		0x93
56 #define MHL_TX_DISC_CTRL5_REG		0x94
57 #define MHL_TX_DISC_CTRL6_REG		0x95
58 #define MHL_TX_DISC_CTRL7_REG		0x96
59 #define MHL_TX_DISC_CTRL8_REG		0x97
60 #define MHL_TX_STAT2_REG		0x99
61 #define MHL_TX_MHLTX_CTL1_REG		0xA0
62 #define MHL_TX_MHLTX_CTL2_REG		0xA1
63 #define MHL_TX_MHLTX_CTL4_REG		0xA3
64 #define MHL_TX_MHLTX_CTL6_REG		0xA5
65 #define MHL_TX_MHLTX_CTL7_REG		0xA6
66 
67 #define RSEN_STATUS			BIT(2)
68 #define HPD_CHANGE_INT			BIT(6)
69 #define RSEN_CHANGE_INT			BIT(5)
70 #define RGND_READY_INT			BIT(6)
71 #define VBUS_LOW_INT			BIT(5)
72 #define CBUS_LKOUT_INT			BIT(4)
73 #define MHL_DISC_FAIL_INT		BIT(3)
74 #define MHL_EST_INT			BIT(2)
75 #define HPD_CHANGE_INT_MASK		BIT(6)
76 #define RSEN_CHANGE_INT_MASK		BIT(5)
77 
78 #define RGND_READY_MASK			BIT(6)
79 #define CBUS_LKOUT_MASK			BIT(4)
80 #define MHL_DISC_FAIL_MASK		BIT(3)
81 #define MHL_EST_MASK			BIT(2)
82 
83 #define SKIP_GND			BIT(6)
84 
85 #define ATT_THRESH_SHIFT		0x04
86 #define ATT_THRESH_MASK			(0x03 << ATT_THRESH_SHIFT)
87 #define USB_D_OEN			BIT(3)
88 #define DEGLITCH_TIME_MASK		0x07
89 #define DEGLITCH_TIME_2MS		0
90 #define DEGLITCH_TIME_4MS		1
91 #define DEGLITCH_TIME_8MS		2
92 #define DEGLITCH_TIME_16MS		3
93 #define DEGLITCH_TIME_40MS		4
94 #define DEGLITCH_TIME_50MS		5
95 #define DEGLITCH_TIME_60MS		6
96 #define DEGLITCH_TIME_128MS		7
97 
98 #define USB_D_OVR			BIT(7)
99 #define USB_ID_OVR			BIT(6)
100 #define DVRFLT_SEL			BIT(5)
101 #define BLOCK_RGND_INT			BIT(4)
102 #define SKIP_DEG			BIT(3)
103 #define CI2CA_POL			BIT(2)
104 #define CI2CA_WKUP			BIT(1)
105 #define SINGLE_ATT			BIT(0)
106 
107 #define USB_D_ODN			BIT(5)
108 #define VBUS_CHECK			BIT(2)
109 #define RGND_INTP_MASK			0x03
110 #define RGND_INTP_OPEN			0
111 #define RGND_INTP_2K			1
112 #define RGND_INTP_1K			2
113 #define RGND_INTP_SHORT			3
114 
115 /* HDMI registers */
116 #define HDMI_RX_TMDS0_CCTRL1_REG	0x10
117 #define HDMI_RX_TMDS_CLK_EN_REG		0x11
118 #define HDMI_RX_TMDS_CH_EN_REG		0x12
119 #define HDMI_RX_PLL_CALREFSEL_REG	0x17
120 #define HDMI_RX_PLL_VCOCAL_REG		0x1A
121 #define HDMI_RX_EQ_DATA0_REG		0x22
122 #define HDMI_RX_EQ_DATA1_REG		0x23
123 #define HDMI_RX_EQ_DATA2_REG		0x24
124 #define HDMI_RX_EQ_DATA3_REG		0x25
125 #define HDMI_RX_EQ_DATA4_REG		0x26
126 #define HDMI_RX_TMDS_ZONE_CTRL_REG	0x4C
127 #define HDMI_RX_TMDS_MODE_CTRL_REG	0x4D
128 
129 /* CBUS registers */
130 #define CBUS_INT_STATUS_1_REG		0x08
131 #define CBUS_INTR1_ENABLE_REG		0x09
132 #define CBUS_MSC_REQ_ABORT_REASON_REG	0x0D
133 #define CBUS_INT_STATUS_2_REG		0x1E
134 #define CBUS_INTR2_ENABLE_REG		0x1F
135 #define CBUS_LINK_CONTROL_2_REG		0x31
136 #define CBUS_MHL_STATUS_REG_0		0xB0
137 #define CBUS_MHL_STATUS_REG_1		0xB1
138 
139 #define BIT_CBUS_RESET			BIT(3)
140 #define SET_HPD_DOWNSTREAM		BIT(6)
141 
142 /* TPI registers */
143 #define TPI_DPD_REG			0x3D
144 
145 /* Timeouts in msec */
146 #define T_SRC_VBUS_CBUS_TO_STABLE	200
147 #define T_SRC_CBUS_FLOAT		100
148 #define T_SRC_CBUS_DEGLITCH		2
149 #define T_SRC_RXSENSE_DEGLITCH		110
150 
151 #define MHL1_MAX_CLK			75000 /* in kHz */
152 
153 #define I2C_TPI_ADDR			0x3D
154 #define I2C_HDMI_ADDR			0x49
155 #define I2C_CBUS_ADDR			0x64
156 
157 enum sii9234_state {
158 	ST_OFF,
159 	ST_D3,
160 	ST_RGND_INIT,
161 	ST_RGND_1K,
162 	ST_RSEN_HIGH,
163 	ST_MHL_ESTABLISHED,
164 	ST_FAILURE_DISCOVERY,
165 	ST_FAILURE,
166 };
167 
168 struct sii9234 {
169 	struct i2c_client *client[4];
170 	struct drm_bridge bridge;
171 	struct device *dev;
172 	struct gpio_desc *gpio_reset;
173 	int i2c_error;
174 	struct regulator_bulk_data supplies[4];
175 
176 	struct mutex lock; /* Protects fields below and device registers */
177 	enum sii9234_state state;
178 };
179 
180 enum sii9234_client_id {
181 	I2C_MHL,
182 	I2C_TPI,
183 	I2C_HDMI,
184 	I2C_CBUS,
185 };
186 
187 static const char * const sii9234_client_name[] = {
188 	[I2C_MHL] = "MHL",
189 	[I2C_TPI] = "TPI",
190 	[I2C_HDMI] = "HDMI",
191 	[I2C_CBUS] = "CBUS",
192 };
193 
194 static int sii9234_writeb(struct sii9234 *ctx, int id, int offset,
195 			  int value)
196 {
197 	int ret;
198 	struct i2c_client *client = ctx->client[id];
199 
200 	if (ctx->i2c_error)
201 		return ctx->i2c_error;
202 
203 	ret = i2c_smbus_write_byte_data(client, offset, value);
204 	if (ret < 0)
205 		dev_err(ctx->dev, "writeb: %4s[0x%02x] <- 0x%02x\n",
206 			sii9234_client_name[id], offset, value);
207 	ctx->i2c_error = ret;
208 
209 	return ret;
210 }
211 
212 static int sii9234_writebm(struct sii9234 *ctx, int id, int offset,
213 			   int value, int mask)
214 {
215 	int ret;
216 	struct i2c_client *client = ctx->client[id];
217 
218 	if (ctx->i2c_error)
219 		return ctx->i2c_error;
220 
221 	ret = i2c_smbus_write_byte(client, offset);
222 	if (ret < 0) {
223 		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
224 			sii9234_client_name[id], offset, value);
225 		ctx->i2c_error = ret;
226 		return ret;
227 	}
228 
229 	ret = i2c_smbus_read_byte(client);
230 	if (ret < 0) {
231 		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
232 			sii9234_client_name[id], offset, value);
233 		ctx->i2c_error = ret;
234 		return ret;
235 	}
236 
237 	value = (value & mask) | (ret & ~mask);
238 
239 	ret = i2c_smbus_write_byte_data(client, offset, value);
240 	if (ret < 0) {
241 		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
242 			sii9234_client_name[id], offset, value);
243 		ctx->i2c_error = ret;
244 	}
245 
246 	return ret;
247 }
248 
249 static int sii9234_readb(struct sii9234 *ctx, int id, int offset)
250 {
251 	int ret;
252 	struct i2c_client *client = ctx->client[id];
253 
254 	if (ctx->i2c_error)
255 		return ctx->i2c_error;
256 
257 	ret = i2c_smbus_write_byte(client, offset);
258 	if (ret < 0) {
259 		dev_err(ctx->dev, "readb: %4s[0x%02x]\n",
260 			sii9234_client_name[id], offset);
261 		ctx->i2c_error = ret;
262 		return ret;
263 	}
264 
265 	ret = i2c_smbus_read_byte(client);
266 	if (ret < 0) {
267 		dev_err(ctx->dev, "readb: %4s[0x%02x]\n",
268 			sii9234_client_name[id], offset);
269 		ctx->i2c_error = ret;
270 	}
271 
272 	return ret;
273 }
274 
275 static int sii9234_clear_error(struct sii9234 *ctx)
276 {
277 	int ret = ctx->i2c_error;
278 
279 	ctx->i2c_error = 0;
280 
281 	return ret;
282 }
283 
284 #define mhl_tx_writeb(sii9234, offset, value) \
285 	sii9234_writeb(sii9234, I2C_MHL, offset, value)
286 #define mhl_tx_writebm(sii9234, offset, value, mask) \
287 	sii9234_writebm(sii9234, I2C_MHL, offset, value, mask)
288 #define mhl_tx_readb(sii9234, offset) \
289 	sii9234_readb(sii9234, I2C_MHL, offset)
290 #define cbus_writeb(sii9234, offset, value) \
291 	sii9234_writeb(sii9234, I2C_CBUS, offset, value)
292 #define cbus_writebm(sii9234, offset, value, mask) \
293 	sii9234_writebm(sii9234, I2C_CBUS, offset, value, mask)
294 #define cbus_readb(sii9234, offset) \
295 	sii9234_readb(sii9234, I2C_CBUS, offset)
296 #define hdmi_writeb(sii9234, offset, value) \
297 	sii9234_writeb(sii9234, I2C_HDMI, offset, value)
298 #define hdmi_writebm(sii9234, offset, value, mask) \
299 	sii9234_writebm(sii9234, I2C_HDMI, offset, value, mask)
300 #define hdmi_readb(sii9234, offset) \
301 	sii9234_readb(sii9234, I2C_HDMI, offset)
302 #define tpi_writeb(sii9234, offset, value) \
303 	sii9234_writeb(sii9234, I2C_TPI, offset, value)
304 #define tpi_writebm(sii9234, offset, value, mask) \
305 	sii9234_writebm(sii9234, I2C_TPI, offset, value, mask)
306 #define tpi_readb(sii9234, offset) \
307 	sii9234_readb(sii9234, I2C_TPI, offset)
308 
309 static u8 sii9234_tmds_control(struct sii9234 *ctx, bool enable)
310 {
311 	mhl_tx_writebm(ctx, MHL_TX_TMDS_CCTRL, enable ? ~0 : 0,
312 		       BIT_TMDS_CCTRL_TMDS_OE);
313 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, enable ? ~0 : 0,
314 		       MHL_HPD_OUT_OVR_EN | MHL_HPD_OUT_OVR_VAL);
315 	return sii9234_clear_error(ctx);
316 }
317 
318 static int sii9234_cbus_reset(struct sii9234 *ctx)
319 {
320 	int i;
321 
322 	mhl_tx_writebm(ctx, MHL_TX_SRST, ~0, BIT_CBUS_RESET);
323 	msleep(T_SRC_CBUS_DEGLITCH);
324 	mhl_tx_writebm(ctx, MHL_TX_SRST, 0, BIT_CBUS_RESET);
325 
326 	for (i = 0; i < 4; i++) {
327 		/*
328 		 * Enable WRITE_STAT interrupt for writes to all
329 		 * 4 MSC Status registers.
330 		 */
331 		cbus_writeb(ctx, 0xE0 + i, 0xF2);
332 		/*
333 		 * Enable SET_INT interrupt for writes to all
334 		 * 4 MSC Interrupt registers.
335 		 */
336 		cbus_writeb(ctx, 0xF0 + i, 0xF2);
337 	}
338 
339 	return sii9234_clear_error(ctx);
340 }
341 
342 /* Require to chek mhl imformation of samsung in cbus_init_register */
343 static int sii9234_cbus_init(struct sii9234 *ctx)
344 {
345 	cbus_writeb(ctx, 0x07, 0xF2);
346 	cbus_writeb(ctx, 0x40, 0x03);
347 	cbus_writeb(ctx, 0x42, 0x06);
348 	cbus_writeb(ctx, 0x36, 0x0C);
349 	cbus_writeb(ctx, 0x3D, 0xFD);
350 	cbus_writeb(ctx, 0x1C, 0x01);
351 	cbus_writeb(ctx, 0x1D, 0x0F);
352 	cbus_writeb(ctx, 0x44, 0x02);
353 	/* Setup our devcap */
354 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_DEV_STATE, 0x00);
355 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_MHL_VERSION,
356 		    SII9234_MHL_VERSION);
357 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_CAT,
358 		    MHL_DCAP_CAT_SOURCE);
359 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_ADOPTER_ID_H, 0x01);
360 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_ADOPTER_ID_L, 0x41);
361 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_VID_LINK_MODE,
362 		    MHL_DCAP_VID_LINK_RGB444 | MHL_DCAP_VID_LINK_YCBCR444);
363 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_VIDEO_TYPE,
364 		    MHL_DCAP_VT_GRAPHICS);
365 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_LOG_DEV_MAP,
366 		    MHL_DCAP_LD_GUI);
367 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_BANDWIDTH, 0x0F);
368 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_FEATURE_FLAG,
369 		    MHL_DCAP_FEATURE_RCP_SUPPORT | MHL_DCAP_FEATURE_RAP_SUPPORT
370 			| MHL_DCAP_FEATURE_SP_SUPPORT);
371 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_DEVICE_ID_H, 0x0);
372 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_DEVICE_ID_L, 0x0);
373 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_SCRATCHPAD_SIZE,
374 		    SII9234_SCRATCHPAD_SIZE);
375 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_INT_STAT_SIZE,
376 		    SII9234_INT_STAT_SIZE);
377 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_RESERVED, 0);
378 	cbus_writebm(ctx, 0x31, 0x0C, 0x0C);
379 	cbus_writeb(ctx, 0x30, 0x01);
380 	cbus_writebm(ctx, 0x3C, 0x30, 0x38);
381 	cbus_writebm(ctx, 0x22, 0x0D, 0x0F);
382 	cbus_writebm(ctx, 0x2E, 0x15, 0x15);
383 	cbus_writeb(ctx, CBUS_INTR1_ENABLE_REG, 0);
384 	cbus_writeb(ctx, CBUS_INTR2_ENABLE_REG, 0);
385 
386 	return sii9234_clear_error(ctx);
387 }
388 
389 static void force_usb_id_switch_open(struct sii9234 *ctx)
390 {
391 	/* Disable CBUS discovery */
392 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, 0, 0x01);
393 	/* Force USB ID switch to open */
394 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, USB_ID_OVR);
395 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL3_REG, ~0, 0x86);
396 	/* Force upstream HPD to 0 when not in MHL mode. */
397 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 0x30);
398 }
399 
400 static void release_usb_id_switch_open(struct sii9234 *ctx)
401 {
402 	msleep(T_SRC_CBUS_FLOAT);
403 	/* Clear USB ID switch to open */
404 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, 0, USB_ID_OVR);
405 	/* Enable CBUS discovery */
406 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, ~0, 0x01);
407 }
408 
409 static int sii9234_power_init(struct sii9234 *ctx)
410 {
411 	/* Force the SiI9234 into the D0 state. */
412 	tpi_writeb(ctx, TPI_DPD_REG, 0x3F);
413 	/* Enable TxPLL Clock */
414 	hdmi_writeb(ctx, HDMI_RX_TMDS_CLK_EN_REG, 0x01);
415 	/* Enable Tx Clock Path & Equalizer */
416 	hdmi_writeb(ctx, HDMI_RX_TMDS_CH_EN_REG, 0x15);
417 	/* Power Up TMDS */
418 	mhl_tx_writeb(ctx, 0x08, 0x35);
419 	return sii9234_clear_error(ctx);
420 }
421 
422 static int sii9234_hdmi_init(struct sii9234 *ctx)
423 {
424 	hdmi_writeb(ctx, HDMI_RX_TMDS0_CCTRL1_REG, 0xC1);
425 	hdmi_writeb(ctx, HDMI_RX_PLL_CALREFSEL_REG, 0x03);
426 	hdmi_writeb(ctx, HDMI_RX_PLL_VCOCAL_REG, 0x20);
427 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA0_REG, 0x8A);
428 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA1_REG, 0x6A);
429 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA2_REG, 0xAA);
430 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA3_REG, 0xCA);
431 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA4_REG, 0xEA);
432 	hdmi_writeb(ctx, HDMI_RX_TMDS_ZONE_CTRL_REG, 0xA0);
433 	hdmi_writeb(ctx, HDMI_RX_TMDS_MODE_CTRL_REG, 0x00);
434 	mhl_tx_writeb(ctx, MHL_TX_TMDS_CCTRL, 0x34);
435 	hdmi_writeb(ctx, 0x45, 0x44);
436 	hdmi_writeb(ctx, 0x31, 0x0A);
437 	hdmi_writeb(ctx, HDMI_RX_TMDS0_CCTRL1_REG, 0xC1);
438 
439 	return sii9234_clear_error(ctx);
440 }
441 
442 static int sii9234_mhl_tx_ctl_int(struct sii9234 *ctx)
443 {
444 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL1_REG, 0xD0);
445 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL2_REG, 0xFC);
446 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL4_REG, 0xEB);
447 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL7_REG, 0x0C);
448 
449 	return sii9234_clear_error(ctx);
450 }
451 
452 static int sii9234_reset(struct sii9234 *ctx)
453 {
454 	int ret;
455 
456 	sii9234_clear_error(ctx);
457 
458 	ret = sii9234_power_init(ctx);
459 	if (ret < 0)
460 		return ret;
461 	ret = sii9234_cbus_reset(ctx);
462 	if (ret < 0)
463 		return ret;
464 	ret = sii9234_hdmi_init(ctx);
465 	if (ret < 0)
466 		return ret;
467 	ret = sii9234_mhl_tx_ctl_int(ctx);
468 	if (ret < 0)
469 		return ret;
470 
471 	/* Enable HDCP Compliance safety */
472 	mhl_tx_writeb(ctx, 0x2B, 0x01);
473 	/* CBUS discovery cycle time for each drive and float = 150us */
474 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, 0x04, 0x06);
475 	/* Clear bit 6 (reg_skip_rgnd) */
476 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL2_REG, (1 << 7) /* Reserved */
477 		      | 2 << ATT_THRESH_SHIFT | DEGLITCH_TIME_50MS);
478 	/*
479 	 * Changed from 66 to 65 for 94[1:0] = 01 = 5k reg_cbusmhl_pup_sel
480 	 * 1.8V CBUS VTH & GND threshold
481 	 * to meet CTS 3.3.7.2 spec
482 	 */
483 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL5_REG, 0x77);
484 	cbus_writebm(ctx, CBUS_LINK_CONTROL_2_REG, ~0, MHL_INIT_TIMEOUT);
485 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL6_REG, 0xA0);
486 	/* RGND & single discovery attempt (RGND blocking) */
487 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL6_REG, BLOCK_RGND_INT |
488 		      DVRFLT_SEL | SINGLE_ATT);
489 	/* Use VBUS path of discovery state machine */
490 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL8_REG, 0);
491 	/* 0x92[3] sets the CBUS / ID switch */
492 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, USB_ID_OVR);
493 	/*
494 	 * To allow RGND engine to operate correctly.
495 	 * When moving the chip from D2 to D0 (power up, init regs)
496 	 * the values should be
497 	 * 94[1:0] = 01  reg_cbusmhl_pup_sel[1:0] should be set for 5k
498 	 * 93[7:6] = 10  reg_cbusdisc_pup_sel[1:0] should be
499 	 * set for 10k (default)
500 	 * 93[5:4] = 00  reg_cbusidle_pup_sel[1:0] = open (default)
501 	 */
502 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL3_REG, ~0, 0x86);
503 	/*
504 	 * Change from CC to 8C to match 5K
505 	 * to meet CTS 3.3.72 spec
506 	 */
507 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, ~0, 0x8C);
508 	/* Configure the interrupt as active high */
509 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 0x06);
510 
511 	msleep(25);
512 
513 	/* Release usb_id switch */
514 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, 0,  USB_ID_OVR);
515 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL1_REG, 0x27);
516 
517 	ret = sii9234_clear_error(ctx);
518 	if (ret < 0)
519 		return ret;
520 	ret = sii9234_cbus_init(ctx);
521 	if (ret < 0)
522 		return ret;
523 
524 	/* Enable Auto soft reset on SCDT = 0 */
525 	mhl_tx_writeb(ctx, 0x05, 0x04);
526 	/* HDMI Transcode mode enable */
527 	mhl_tx_writeb(ctx, 0x0D, 0x1C);
528 	mhl_tx_writeb(ctx, MHL_TX_INTR4_ENABLE_REG,
529 		      RGND_READY_MASK | CBUS_LKOUT_MASK
530 			| MHL_DISC_FAIL_MASK | MHL_EST_MASK);
531 	mhl_tx_writeb(ctx, MHL_TX_INTR1_ENABLE_REG, 0x60);
532 
533 	/* This point is very important before measure RGND impedance */
534 	force_usb_id_switch_open(ctx);
535 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, 0, 0xF0);
536 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL5_REG, 0, 0x03);
537 	release_usb_id_switch_open(ctx);
538 
539 	/* Force upstream HPD to 0 when not in MHL mode */
540 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 1 << 5);
541 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, ~0, 1 << 4);
542 
543 	return sii9234_clear_error(ctx);
544 }
545 
546 static int sii9234_goto_d3(struct sii9234 *ctx)
547 {
548 	int ret;
549 
550 	dev_dbg(ctx->dev, "sii9234: detection started d3\n");
551 
552 	ret = sii9234_reset(ctx);
553 	if (ret < 0)
554 		goto exit;
555 
556 	hdmi_writeb(ctx, 0x01, 0x03);
557 	tpi_writebm(ctx, TPI_DPD_REG, 0, 1);
558 	/* I2C above is expected to fail because power goes down */
559 	sii9234_clear_error(ctx);
560 
561 	ctx->state = ST_D3;
562 
563 	return 0;
564  exit:
565 	dev_err(ctx->dev, "%s failed\n", __func__);
566 	return -1;
567 }
568 
569 static int sii9234_hw_on(struct sii9234 *ctx)
570 {
571 	return regulator_bulk_enable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
572 }
573 
574 static void sii9234_hw_off(struct sii9234 *ctx)
575 {
576 	gpiod_set_value(ctx->gpio_reset, 1);
577 	msleep(20);
578 	regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
579 }
580 
581 static void sii9234_hw_reset(struct sii9234 *ctx)
582 {
583 	gpiod_set_value(ctx->gpio_reset, 1);
584 	msleep(20);
585 	gpiod_set_value(ctx->gpio_reset, 0);
586 }
587 
588 static void sii9234_cable_in(struct sii9234 *ctx)
589 {
590 	int ret;
591 
592 	mutex_lock(&ctx->lock);
593 	if (ctx->state != ST_OFF)
594 		goto unlock;
595 	ret = sii9234_hw_on(ctx);
596 	if (ret < 0)
597 		goto unlock;
598 
599 	sii9234_hw_reset(ctx);
600 	sii9234_goto_d3(ctx);
601 	/* To avoid irq storm, when hw is in meta state */
602 	enable_irq(to_i2c_client(ctx->dev)->irq);
603 
604 unlock:
605 	mutex_unlock(&ctx->lock);
606 }
607 
608 static void sii9234_cable_out(struct sii9234 *ctx)
609 {
610 	mutex_lock(&ctx->lock);
611 
612 	if (ctx->state == ST_OFF)
613 		goto unlock;
614 
615 	disable_irq(to_i2c_client(ctx->dev)->irq);
616 	tpi_writeb(ctx, TPI_DPD_REG, 0);
617 	/* Turn on&off hpd festure for only QCT HDMI */
618 	sii9234_hw_off(ctx);
619 
620 	ctx->state = ST_OFF;
621 
622 unlock:
623 	mutex_unlock(&ctx->lock);
624 }
625 
626 static enum sii9234_state sii9234_rgnd_ready_irq(struct sii9234 *ctx)
627 {
628 	int value;
629 
630 	if (ctx->state == ST_D3) {
631 		int ret;
632 
633 		dev_dbg(ctx->dev, "RGND_READY_INT\n");
634 		sii9234_hw_reset(ctx);
635 
636 		ret = sii9234_reset(ctx);
637 		if (ret < 0) {
638 			dev_err(ctx->dev, "sii9234_reset() failed\n");
639 			return ST_FAILURE;
640 		}
641 
642 		return ST_RGND_INIT;
643 	}
644 
645 	/* Got interrupt in inappropriate state */
646 	if (ctx->state != ST_RGND_INIT)
647 		return ST_FAILURE;
648 
649 	value = mhl_tx_readb(ctx, MHL_TX_STAT2_REG);
650 	if (sii9234_clear_error(ctx))
651 		return ST_FAILURE;
652 
653 	if ((value & RGND_INTP_MASK) != RGND_INTP_1K) {
654 		dev_warn(ctx->dev, "RGND is not 1k\n");
655 		return ST_RGND_INIT;
656 	}
657 	dev_dbg(ctx->dev, "RGND 1K!!\n");
658 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, ~0, 0x8C);
659 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL5_REG, 0x77);
660 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, 0x05);
661 	if (sii9234_clear_error(ctx))
662 		return ST_FAILURE;
663 
664 	msleep(T_SRC_VBUS_CBUS_TO_STABLE);
665 	return ST_RGND_1K;
666 }
667 
668 static enum sii9234_state sii9234_mhl_established(struct sii9234 *ctx)
669 {
670 	dev_dbg(ctx->dev, "mhl est interrupt\n");
671 
672 	/* Discovery override */
673 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL1_REG, 0x10);
674 	/* Increase DDC translation layer timer (byte mode) */
675 	cbus_writeb(ctx, 0x07, 0x32);
676 	cbus_writebm(ctx, 0x44, ~0, 1 << 1);
677 	/* Keep the discovery enabled. Need RGND interrupt */
678 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, ~0, 1);
679 	mhl_tx_writeb(ctx, MHL_TX_INTR1_ENABLE_REG,
680 		      RSEN_CHANGE_INT_MASK | HPD_CHANGE_INT_MASK);
681 
682 	if (sii9234_clear_error(ctx))
683 		return ST_FAILURE;
684 
685 	return ST_MHL_ESTABLISHED;
686 }
687 
688 static enum sii9234_state sii9234_hpd_change(struct sii9234 *ctx)
689 {
690 	int value;
691 
692 	value = cbus_readb(ctx, CBUS_MSC_REQ_ABORT_REASON_REG);
693 	if (sii9234_clear_error(ctx))
694 		return ST_FAILURE;
695 
696 	if (value & SET_HPD_DOWNSTREAM) {
697 		/* Downstream HPD High, Enable TMDS */
698 		sii9234_tmds_control(ctx, true);
699 	} else {
700 		/* Downstream HPD Low, Disable TMDS */
701 		sii9234_tmds_control(ctx, false);
702 	}
703 
704 	return ctx->state;
705 }
706 
707 static enum sii9234_state sii9234_rsen_change(struct sii9234 *ctx)
708 {
709 	int value;
710 
711 	/* Work_around code to handle wrong interrupt */
712 	if (ctx->state != ST_RGND_1K) {
713 		dev_err(ctx->dev, "RSEN_HIGH without RGND_1K\n");
714 		return ST_FAILURE;
715 	}
716 	value = mhl_tx_readb(ctx, MHL_TX_SYSSTAT_REG);
717 	if (value < 0)
718 		return ST_FAILURE;
719 
720 	if (value & RSEN_STATUS) {
721 		dev_dbg(ctx->dev, "MHL cable connected.. RSEN High\n");
722 		return ST_RSEN_HIGH;
723 	}
724 	dev_dbg(ctx->dev, "RSEN lost\n");
725 	/*
726 	 * Once RSEN loss is confirmed,we need to check
727 	 * based on cable status and chip power status,whether
728 	 * it is SINK Loss(HDMI cable not connected, TV Off)
729 	 * or MHL cable disconnection
730 	 * TODO: Define the below mhl_disconnection()
731 	 */
732 	msleep(T_SRC_RXSENSE_DEGLITCH);
733 	value = mhl_tx_readb(ctx, MHL_TX_SYSSTAT_REG);
734 	if (value < 0)
735 		return ST_FAILURE;
736 	dev_dbg(ctx->dev, "sys_stat: %x\n", value);
737 
738 	if (value & RSEN_STATUS) {
739 		dev_dbg(ctx->dev, "RSEN recovery\n");
740 		return ST_RSEN_HIGH;
741 	}
742 	dev_dbg(ctx->dev, "RSEN Really LOW\n");
743 	/* To meet CTS 3.3.22.2 spec */
744 	sii9234_tmds_control(ctx, false);
745 	force_usb_id_switch_open(ctx);
746 	release_usb_id_switch_open(ctx);
747 
748 	return ST_FAILURE;
749 }
750 
751 static irqreturn_t sii9234_irq_thread(int irq, void *data)
752 {
753 	struct sii9234 *ctx = data;
754 	int intr1, intr4;
755 	int intr1_en, intr4_en;
756 	int cbus_intr1, cbus_intr2;
757 
758 	dev_dbg(ctx->dev, "%s\n", __func__);
759 
760 	mutex_lock(&ctx->lock);
761 
762 	intr1 = mhl_tx_readb(ctx, MHL_TX_INTR1_REG);
763 	intr4 = mhl_tx_readb(ctx, MHL_TX_INTR4_REG);
764 	intr1_en = mhl_tx_readb(ctx, MHL_TX_INTR1_ENABLE_REG);
765 	intr4_en = mhl_tx_readb(ctx, MHL_TX_INTR4_ENABLE_REG);
766 	cbus_intr1 = cbus_readb(ctx, CBUS_INT_STATUS_1_REG);
767 	cbus_intr2 = cbus_readb(ctx, CBUS_INT_STATUS_2_REG);
768 
769 	if (sii9234_clear_error(ctx))
770 		goto done;
771 
772 	dev_dbg(ctx->dev, "irq %02x/%02x %02x/%02x %02x/%02x\n",
773 		intr1, intr1_en, intr4, intr4_en, cbus_intr1, cbus_intr2);
774 
775 	if (intr4 & RGND_READY_INT)
776 		ctx->state = sii9234_rgnd_ready_irq(ctx);
777 	if (intr1 & RSEN_CHANGE_INT)
778 		ctx->state = sii9234_rsen_change(ctx);
779 	if (intr4 & MHL_EST_INT)
780 		ctx->state = sii9234_mhl_established(ctx);
781 	if (intr1 & HPD_CHANGE_INT)
782 		ctx->state = sii9234_hpd_change(ctx);
783 	if (intr4 & CBUS_LKOUT_INT)
784 		ctx->state = ST_FAILURE;
785 	if (intr4 & MHL_DISC_FAIL_INT)
786 		ctx->state = ST_FAILURE_DISCOVERY;
787 
788  done:
789 	/* Clean interrupt status and pending flags */
790 	mhl_tx_writeb(ctx, MHL_TX_INTR1_REG, intr1);
791 	mhl_tx_writeb(ctx, MHL_TX_INTR4_REG, intr4);
792 	cbus_writeb(ctx, CBUS_MHL_STATUS_REG_0, 0xFF);
793 	cbus_writeb(ctx, CBUS_MHL_STATUS_REG_1, 0xFF);
794 	cbus_writeb(ctx, CBUS_INT_STATUS_1_REG, cbus_intr1);
795 	cbus_writeb(ctx, CBUS_INT_STATUS_2_REG, cbus_intr2);
796 
797 	sii9234_clear_error(ctx);
798 
799 	if (ctx->state == ST_FAILURE) {
800 		dev_dbg(ctx->dev, "try to reset after failure\n");
801 		sii9234_hw_reset(ctx);
802 		sii9234_goto_d3(ctx);
803 	}
804 
805 	if (ctx->state == ST_FAILURE_DISCOVERY) {
806 		dev_err(ctx->dev, "discovery failed, no power for MHL?\n");
807 		tpi_writebm(ctx, TPI_DPD_REG, 0, 1);
808 		ctx->state = ST_D3;
809 	}
810 
811 	mutex_unlock(&ctx->lock);
812 
813 	return IRQ_HANDLED;
814 }
815 
816 static int sii9234_init_resources(struct sii9234 *ctx,
817 				  struct i2c_client *client)
818 {
819 	struct i2c_adapter *adapter = client->adapter;
820 	int ret;
821 
822 	if (!ctx->dev->of_node) {
823 		dev_err(ctx->dev, "not DT device\n");
824 		return -ENODEV;
825 	}
826 
827 	ctx->gpio_reset = devm_gpiod_get(ctx->dev, "reset", GPIOD_OUT_LOW);
828 	if (IS_ERR(ctx->gpio_reset)) {
829 		dev_err(ctx->dev, "failed to get reset gpio from DT\n");
830 		return PTR_ERR(ctx->gpio_reset);
831 	}
832 
833 	ctx->supplies[0].supply = "avcc12";
834 	ctx->supplies[1].supply = "avcc33";
835 	ctx->supplies[2].supply = "iovcc18";
836 	ctx->supplies[3].supply = "cvcc12";
837 	ret = devm_regulator_bulk_get(ctx->dev, 4, ctx->supplies);
838 	if (ret) {
839 		if (ret != -EPROBE_DEFER)
840 			dev_err(ctx->dev, "regulator_bulk failed\n");
841 		return ret;
842 	}
843 
844 	ctx->client[I2C_MHL] = client;
845 
846 	ctx->client[I2C_TPI] = devm_i2c_new_dummy_device(&client->dev, adapter,
847 							 I2C_TPI_ADDR);
848 	if (IS_ERR(ctx->client[I2C_TPI])) {
849 		dev_err(ctx->dev, "failed to create TPI client\n");
850 		return PTR_ERR(ctx->client[I2C_TPI]);
851 	}
852 
853 	ctx->client[I2C_HDMI] = devm_i2c_new_dummy_device(&client->dev, adapter,
854 							  I2C_HDMI_ADDR);
855 	if (IS_ERR(ctx->client[I2C_HDMI])) {
856 		dev_err(ctx->dev, "failed to create HDMI RX client\n");
857 		return PTR_ERR(ctx->client[I2C_HDMI]);
858 	}
859 
860 	ctx->client[I2C_CBUS] = devm_i2c_new_dummy_device(&client->dev, adapter,
861 							  I2C_CBUS_ADDR);
862 	if (IS_ERR(ctx->client[I2C_CBUS])) {
863 		dev_err(ctx->dev, "failed to create CBUS client\n");
864 		return PTR_ERR(ctx->client[I2C_CBUS]);
865 	}
866 
867 	return 0;
868 }
869 
870 static enum drm_mode_status sii9234_mode_valid(struct drm_bridge *bridge,
871 					 const struct drm_display_info *info,
872 					 const struct drm_display_mode *mode)
873 {
874 	if (mode->clock > MHL1_MAX_CLK)
875 		return MODE_CLOCK_HIGH;
876 
877 	return MODE_OK;
878 }
879 
880 static const struct drm_bridge_funcs sii9234_bridge_funcs = {
881 	.mode_valid = sii9234_mode_valid,
882 };
883 
884 static int sii9234_probe(struct i2c_client *client)
885 {
886 	struct i2c_adapter *adapter = client->adapter;
887 	struct sii9234 *ctx;
888 	struct device *dev = &client->dev;
889 	int ret;
890 
891 	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
892 	if (!ctx)
893 		return -ENOMEM;
894 
895 	ctx->dev = dev;
896 	mutex_init(&ctx->lock);
897 
898 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
899 		dev_err(dev, "I2C adapter lacks SMBUS feature\n");
900 		return -EIO;
901 	}
902 
903 	if (!client->irq) {
904 		dev_err(dev, "no irq provided\n");
905 		return -EINVAL;
906 	}
907 
908 	irq_set_status_flags(client->irq, IRQ_NOAUTOEN);
909 	ret = devm_request_threaded_irq(dev, client->irq, NULL,
910 					sii9234_irq_thread,
911 					IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
912 					"sii9234", ctx);
913 	if (ret < 0) {
914 		dev_err(dev, "failed to install IRQ handler\n");
915 		return ret;
916 	}
917 
918 	ret = sii9234_init_resources(ctx, client);
919 	if (ret < 0)
920 		return ret;
921 
922 	i2c_set_clientdata(client, ctx);
923 
924 	ctx->bridge.funcs = &sii9234_bridge_funcs;
925 	ctx->bridge.of_node = dev->of_node;
926 	drm_bridge_add(&ctx->bridge);
927 
928 	sii9234_cable_in(ctx);
929 
930 	return 0;
931 }
932 
933 static void sii9234_remove(struct i2c_client *client)
934 {
935 	struct sii9234 *ctx = i2c_get_clientdata(client);
936 
937 	sii9234_cable_out(ctx);
938 	drm_bridge_remove(&ctx->bridge);
939 }
940 
941 static const struct of_device_id sii9234_dt_match[] = {
942 	{ .compatible = "sil,sii9234" },
943 	{ },
944 };
945 MODULE_DEVICE_TABLE(of, sii9234_dt_match);
946 
947 static const struct i2c_device_id sii9234_id[] = {
948 	{ "SII9234", 0 },
949 	{ },
950 };
951 MODULE_DEVICE_TABLE(i2c, sii9234_id);
952 
953 static struct i2c_driver sii9234_driver = {
954 	.driver = {
955 		.name	= "sii9234",
956 		.of_match_table = sii9234_dt_match,
957 	},
958 	.probe = sii9234_probe,
959 	.remove = sii9234_remove,
960 	.id_table = sii9234_id,
961 };
962 
963 module_i2c_driver(sii9234_driver);
964 MODULE_LICENSE("GPL");
965