xref: /openbmc/linux/drivers/gpu/drm/bridge/sii9234.c (revision cd238eff)
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_crtc.h>
17 #include <drm/drm_edid.h>
18 
19 #include <linux/delay.h>
20 #include <linux/err.h>
21 #include <linux/gpio/consumer.h>
22 #include <linux/i2c.h>
23 #include <linux/interrupt.h>
24 #include <linux/irq.h>
25 #include <linux/kernel.h>
26 #include <linux/module.h>
27 #include <linux/mutex.h>
28 #include <linux/regulator/consumer.h>
29 #include <linux/slab.h>
30 
31 #define CBUS_DEVCAP_OFFSET		0x80
32 
33 #define SII9234_MHL_VERSION		0x11
34 #define SII9234_SCRATCHPAD_SIZE		0x10
35 #define SII9234_INT_STAT_SIZE		0x33
36 
37 #define BIT_TMDS_CCTRL_TMDS_OE		BIT(4)
38 #define MHL_HPD_OUT_OVR_EN		BIT(4)
39 #define MHL_HPD_OUT_OVR_VAL		BIT(5)
40 #define MHL_INIT_TIMEOUT		0x0C
41 
42 /* MHL Tx registers and bits */
43 #define MHL_TX_SRST			0x05
44 #define MHL_TX_SYSSTAT_REG		0x09
45 #define MHL_TX_INTR1_REG		0x71
46 #define MHL_TX_INTR4_REG		0x74
47 #define MHL_TX_INTR1_ENABLE_REG		0x75
48 #define MHL_TX_INTR4_ENABLE_REG		0x78
49 #define MHL_TX_INT_CTRL_REG		0x79
50 #define MHL_TX_TMDS_CCTRL		0x80
51 #define MHL_TX_DISC_CTRL1_REG		0x90
52 #define MHL_TX_DISC_CTRL2_REG		0x91
53 #define MHL_TX_DISC_CTRL3_REG		0x92
54 #define MHL_TX_DISC_CTRL4_REG		0x93
55 #define MHL_TX_DISC_CTRL5_REG		0x94
56 #define MHL_TX_DISC_CTRL6_REG		0x95
57 #define MHL_TX_DISC_CTRL7_REG		0x96
58 #define MHL_TX_DISC_CTRL8_REG		0x97
59 #define MHL_TX_STAT2_REG		0x99
60 #define MHL_TX_MHLTX_CTL1_REG		0xA0
61 #define MHL_TX_MHLTX_CTL2_REG		0xA1
62 #define MHL_TX_MHLTX_CTL4_REG		0xA3
63 #define MHL_TX_MHLTX_CTL6_REG		0xA5
64 #define MHL_TX_MHLTX_CTL7_REG		0xA6
65 
66 #define RSEN_STATUS			BIT(2)
67 #define HPD_CHANGE_INT			BIT(6)
68 #define RSEN_CHANGE_INT			BIT(5)
69 #define RGND_READY_INT			BIT(6)
70 #define VBUS_LOW_INT			BIT(5)
71 #define CBUS_LKOUT_INT			BIT(4)
72 #define MHL_DISC_FAIL_INT		BIT(3)
73 #define MHL_EST_INT			BIT(2)
74 #define HPD_CHANGE_INT_MASK		BIT(6)
75 #define RSEN_CHANGE_INT_MASK		BIT(5)
76 
77 #define RGND_READY_MASK			BIT(6)
78 #define CBUS_LKOUT_MASK			BIT(4)
79 #define MHL_DISC_FAIL_MASK		BIT(3)
80 #define MHL_EST_MASK			BIT(2)
81 
82 #define SKIP_GND			BIT(6)
83 
84 #define ATT_THRESH_SHIFT		0x04
85 #define ATT_THRESH_MASK			(0x03 << ATT_THRESH_SHIFT)
86 #define USB_D_OEN			BIT(3)
87 #define DEGLITCH_TIME_MASK		0x07
88 #define DEGLITCH_TIME_2MS		0
89 #define DEGLITCH_TIME_4MS		1
90 #define DEGLITCH_TIME_8MS		2
91 #define DEGLITCH_TIME_16MS		3
92 #define DEGLITCH_TIME_40MS		4
93 #define DEGLITCH_TIME_50MS		5
94 #define DEGLITCH_TIME_60MS		6
95 #define DEGLITCH_TIME_128MS		7
96 
97 #define USB_D_OVR			BIT(7)
98 #define USB_ID_OVR			BIT(6)
99 #define DVRFLT_SEL			BIT(5)
100 #define BLOCK_RGND_INT			BIT(4)
101 #define SKIP_DEG			BIT(3)
102 #define CI2CA_POL			BIT(2)
103 #define CI2CA_WKUP			BIT(1)
104 #define SINGLE_ATT			BIT(0)
105 
106 #define USB_D_ODN			BIT(5)
107 #define VBUS_CHECK			BIT(2)
108 #define RGND_INTP_MASK			0x03
109 #define RGND_INTP_OPEN			0
110 #define RGND_INTP_2K			1
111 #define RGND_INTP_1K			2
112 #define RGND_INTP_SHORT			3
113 
114 /* HDMI registers */
115 #define HDMI_RX_TMDS0_CCTRL1_REG	0x10
116 #define HDMI_RX_TMDS_CLK_EN_REG		0x11
117 #define HDMI_RX_TMDS_CH_EN_REG		0x12
118 #define HDMI_RX_PLL_CALREFSEL_REG	0x17
119 #define HDMI_RX_PLL_VCOCAL_REG		0x1A
120 #define HDMI_RX_EQ_DATA0_REG		0x22
121 #define HDMI_RX_EQ_DATA1_REG		0x23
122 #define HDMI_RX_EQ_DATA2_REG		0x24
123 #define HDMI_RX_EQ_DATA3_REG		0x25
124 #define HDMI_RX_EQ_DATA4_REG		0x26
125 #define HDMI_RX_TMDS_ZONE_CTRL_REG	0x4C
126 #define HDMI_RX_TMDS_MODE_CTRL_REG	0x4D
127 
128 /* CBUS registers */
129 #define CBUS_INT_STATUS_1_REG		0x08
130 #define CBUS_INTR1_ENABLE_REG		0x09
131 #define CBUS_MSC_REQ_ABORT_REASON_REG	0x0D
132 #define CBUS_INT_STATUS_2_REG		0x1E
133 #define CBUS_INTR2_ENABLE_REG		0x1F
134 #define CBUS_LINK_CONTROL_2_REG		0x31
135 #define CBUS_MHL_STATUS_REG_0		0xB0
136 #define CBUS_MHL_STATUS_REG_1		0xB1
137 
138 #define BIT_CBUS_RESET			BIT(3)
139 #define SET_HPD_DOWNSTREAM		BIT(6)
140 
141 /* TPI registers */
142 #define TPI_DPD_REG			0x3D
143 
144 /* Timeouts in msec */
145 #define T_SRC_VBUS_CBUS_TO_STABLE	200
146 #define T_SRC_CBUS_FLOAT		100
147 #define T_SRC_CBUS_DEGLITCH		2
148 #define T_SRC_RXSENSE_DEGLITCH		110
149 
150 #define MHL1_MAX_CLK			75000 /* in kHz */
151 
152 #define I2C_TPI_ADDR			0x3D
153 #define I2C_HDMI_ADDR			0x49
154 #define I2C_CBUS_ADDR			0x64
155 
156 enum sii9234_state {
157 	ST_OFF,
158 	ST_D3,
159 	ST_RGND_INIT,
160 	ST_RGND_1K,
161 	ST_RSEN_HIGH,
162 	ST_MHL_ESTABLISHED,
163 	ST_FAILURE_DISCOVERY,
164 	ST_FAILURE,
165 };
166 
167 struct sii9234 {
168 	struct i2c_client *client[4];
169 	struct drm_bridge bridge;
170 	struct device *dev;
171 	struct gpio_desc *gpio_reset;
172 	int i2c_error;
173 	struct regulator_bulk_data supplies[4];
174 
175 	struct mutex lock; /* Protects fields below and device registers */
176 	enum sii9234_state state;
177 };
178 
179 enum sii9234_client_id {
180 	I2C_MHL,
181 	I2C_TPI,
182 	I2C_HDMI,
183 	I2C_CBUS,
184 };
185 
186 static const char * const sii9234_client_name[] = {
187 	[I2C_MHL] = "MHL",
188 	[I2C_TPI] = "TPI",
189 	[I2C_HDMI] = "HDMI",
190 	[I2C_CBUS] = "CBUS",
191 };
192 
193 static int sii9234_writeb(struct sii9234 *ctx, int id, int offset,
194 			  int value)
195 {
196 	int ret;
197 	struct i2c_client *client = ctx->client[id];
198 
199 	if (ctx->i2c_error)
200 		return ctx->i2c_error;
201 
202 	ret = i2c_smbus_write_byte_data(client, offset, value);
203 	if (ret < 0)
204 		dev_err(ctx->dev, "writeb: %4s[0x%02x] <- 0x%02x\n",
205 			sii9234_client_name[id], offset, value);
206 	ctx->i2c_error = ret;
207 
208 	return ret;
209 }
210 
211 static int sii9234_writebm(struct sii9234 *ctx, int id, int offset,
212 			   int value, int mask)
213 {
214 	int ret;
215 	struct i2c_client *client = ctx->client[id];
216 
217 	if (ctx->i2c_error)
218 		return ctx->i2c_error;
219 
220 	ret = i2c_smbus_write_byte(client, offset);
221 	if (ret < 0) {
222 		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
223 			sii9234_client_name[id], offset, value);
224 		ctx->i2c_error = ret;
225 		return ret;
226 	}
227 
228 	ret = i2c_smbus_read_byte(client);
229 	if (ret < 0) {
230 		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
231 			sii9234_client_name[id], offset, value);
232 		ctx->i2c_error = ret;
233 		return ret;
234 	}
235 
236 	value = (value & mask) | (ret & ~mask);
237 
238 	ret = i2c_smbus_write_byte_data(client, offset, value);
239 	if (ret < 0) {
240 		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
241 			sii9234_client_name[id], offset, value);
242 		ctx->i2c_error = ret;
243 	}
244 
245 	return ret;
246 }
247 
248 static int sii9234_readb(struct sii9234 *ctx, int id, int offset)
249 {
250 	int ret;
251 	struct i2c_client *client = ctx->client[id];
252 
253 	if (ctx->i2c_error)
254 		return ctx->i2c_error;
255 
256 	ret = i2c_smbus_write_byte(client, offset);
257 	if (ret < 0) {
258 		dev_err(ctx->dev, "readb: %4s[0x%02x]\n",
259 			sii9234_client_name[id], offset);
260 		ctx->i2c_error = ret;
261 		return ret;
262 	}
263 
264 	ret = i2c_smbus_read_byte(client);
265 	if (ret < 0) {
266 		dev_err(ctx->dev, "readb: %4s[0x%02x]\n",
267 			sii9234_client_name[id], offset);
268 		ctx->i2c_error = ret;
269 	}
270 
271 	return ret;
272 }
273 
274 static int sii9234_clear_error(struct sii9234 *ctx)
275 {
276 	int ret = ctx->i2c_error;
277 
278 	ctx->i2c_error = 0;
279 
280 	return ret;
281 }
282 
283 #define mhl_tx_writeb(sii9234, offset, value) \
284 	sii9234_writeb(sii9234, I2C_MHL, offset, value)
285 #define mhl_tx_writebm(sii9234, offset, value, mask) \
286 	sii9234_writebm(sii9234, I2C_MHL, offset, value, mask)
287 #define mhl_tx_readb(sii9234, offset) \
288 	sii9234_readb(sii9234, I2C_MHL, offset)
289 #define cbus_writeb(sii9234, offset, value) \
290 	sii9234_writeb(sii9234, I2C_CBUS, offset, value)
291 #define cbus_writebm(sii9234, offset, value, mask) \
292 	sii9234_writebm(sii9234, I2C_CBUS, offset, value, mask)
293 #define cbus_readb(sii9234, offset) \
294 	sii9234_readb(sii9234, I2C_CBUS, offset)
295 #define hdmi_writeb(sii9234, offset, value) \
296 	sii9234_writeb(sii9234, I2C_HDMI, offset, value)
297 #define hdmi_writebm(sii9234, offset, value, mask) \
298 	sii9234_writebm(sii9234, I2C_HDMI, offset, value, mask)
299 #define hdmi_readb(sii9234, offset) \
300 	sii9234_readb(sii9234, I2C_HDMI, offset)
301 #define tpi_writeb(sii9234, offset, value) \
302 	sii9234_writeb(sii9234, I2C_TPI, offset, value)
303 #define tpi_writebm(sii9234, offset, value, mask) \
304 	sii9234_writebm(sii9234, I2C_TPI, offset, value, mask)
305 #define tpi_readb(sii9234, offset) \
306 	sii9234_readb(sii9234, I2C_TPI, offset)
307 
308 static u8 sii9234_tmds_control(struct sii9234 *ctx, bool enable)
309 {
310 	mhl_tx_writebm(ctx, MHL_TX_TMDS_CCTRL, enable ? ~0 : 0,
311 		       BIT_TMDS_CCTRL_TMDS_OE);
312 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, enable ? ~0 : 0,
313 		       MHL_HPD_OUT_OVR_EN | MHL_HPD_OUT_OVR_VAL);
314 	return sii9234_clear_error(ctx);
315 }
316 
317 static int sii9234_cbus_reset(struct sii9234 *ctx)
318 {
319 	int i;
320 
321 	mhl_tx_writebm(ctx, MHL_TX_SRST, ~0, BIT_CBUS_RESET);
322 	msleep(T_SRC_CBUS_DEGLITCH);
323 	mhl_tx_writebm(ctx, MHL_TX_SRST, 0, BIT_CBUS_RESET);
324 
325 	for (i = 0; i < 4; i++) {
326 		/*
327 		 * Enable WRITE_STAT interrupt for writes to all
328 		 * 4 MSC Status registers.
329 		 */
330 		cbus_writeb(ctx, 0xE0 + i, 0xF2);
331 		/*
332 		 * Enable SET_INT interrupt for writes to all
333 		 * 4 MSC Interrupt registers.
334 		 */
335 		cbus_writeb(ctx, 0xF0 + i, 0xF2);
336 	}
337 
338 	return sii9234_clear_error(ctx);
339 }
340 
341 /* Require to chek mhl imformation of samsung in cbus_init_register */
342 static int sii9234_cbus_init(struct sii9234 *ctx)
343 {
344 	cbus_writeb(ctx, 0x07, 0xF2);
345 	cbus_writeb(ctx, 0x40, 0x03);
346 	cbus_writeb(ctx, 0x42, 0x06);
347 	cbus_writeb(ctx, 0x36, 0x0C);
348 	cbus_writeb(ctx, 0x3D, 0xFD);
349 	cbus_writeb(ctx, 0x1C, 0x01);
350 	cbus_writeb(ctx, 0x1D, 0x0F);
351 	cbus_writeb(ctx, 0x44, 0x02);
352 	/* Setup our devcap */
353 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_DEV_STATE, 0x00);
354 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_MHL_VERSION,
355 		    SII9234_MHL_VERSION);
356 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_CAT,
357 		    MHL_DCAP_CAT_SOURCE);
358 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_ADOPTER_ID_H, 0x01);
359 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_ADOPTER_ID_L, 0x41);
360 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_VID_LINK_MODE,
361 		    MHL_DCAP_VID_LINK_RGB444 | MHL_DCAP_VID_LINK_YCBCR444);
362 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_VIDEO_TYPE,
363 		    MHL_DCAP_VT_GRAPHICS);
364 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_LOG_DEV_MAP,
365 		    MHL_DCAP_LD_GUI);
366 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_BANDWIDTH, 0x0F);
367 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_FEATURE_FLAG,
368 		    MHL_DCAP_FEATURE_RCP_SUPPORT | MHL_DCAP_FEATURE_RAP_SUPPORT
369 			| MHL_DCAP_FEATURE_SP_SUPPORT);
370 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_DEVICE_ID_H, 0x0);
371 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_DEVICE_ID_L, 0x0);
372 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_SCRATCHPAD_SIZE,
373 		    SII9234_SCRATCHPAD_SIZE);
374 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_INT_STAT_SIZE,
375 		    SII9234_INT_STAT_SIZE);
376 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_RESERVED, 0);
377 	cbus_writebm(ctx, 0x31, 0x0C, 0x0C);
378 	cbus_writeb(ctx, 0x30, 0x01);
379 	cbus_writebm(ctx, 0x3C, 0x30, 0x38);
380 	cbus_writebm(ctx, 0x22, 0x0D, 0x0F);
381 	cbus_writebm(ctx, 0x2E, 0x15, 0x15);
382 	cbus_writeb(ctx, CBUS_INTR1_ENABLE_REG, 0);
383 	cbus_writeb(ctx, CBUS_INTR2_ENABLE_REG, 0);
384 
385 	return sii9234_clear_error(ctx);
386 }
387 
388 static void force_usb_id_switch_open(struct sii9234 *ctx)
389 {
390 	/* Disable CBUS discovery */
391 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, 0, 0x01);
392 	/* Force USB ID switch to open */
393 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, USB_ID_OVR);
394 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL3_REG, ~0, 0x86);
395 	/* Force upstream HPD to 0 when not in MHL mode. */
396 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 0x30);
397 }
398 
399 static void release_usb_id_switch_open(struct sii9234 *ctx)
400 {
401 	msleep(T_SRC_CBUS_FLOAT);
402 	/* Clear USB ID switch to open */
403 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, 0, USB_ID_OVR);
404 	/* Enable CBUS discovery */
405 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, ~0, 0x01);
406 }
407 
408 static int sii9234_power_init(struct sii9234 *ctx)
409 {
410 	/* Force the SiI9234 into the D0 state. */
411 	tpi_writeb(ctx, TPI_DPD_REG, 0x3F);
412 	/* Enable TxPLL Clock */
413 	hdmi_writeb(ctx, HDMI_RX_TMDS_CLK_EN_REG, 0x01);
414 	/* Enable Tx Clock Path & Equalizer */
415 	hdmi_writeb(ctx, HDMI_RX_TMDS_CH_EN_REG, 0x15);
416 	/* Power Up TMDS */
417 	mhl_tx_writeb(ctx, 0x08, 0x35);
418 	return sii9234_clear_error(ctx);
419 }
420 
421 static int sii9234_hdmi_init(struct sii9234 *ctx)
422 {
423 	hdmi_writeb(ctx, HDMI_RX_TMDS0_CCTRL1_REG, 0xC1);
424 	hdmi_writeb(ctx, HDMI_RX_PLL_CALREFSEL_REG, 0x03);
425 	hdmi_writeb(ctx, HDMI_RX_PLL_VCOCAL_REG, 0x20);
426 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA0_REG, 0x8A);
427 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA1_REG, 0x6A);
428 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA2_REG, 0xAA);
429 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA3_REG, 0xCA);
430 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA4_REG, 0xEA);
431 	hdmi_writeb(ctx, HDMI_RX_TMDS_ZONE_CTRL_REG, 0xA0);
432 	hdmi_writeb(ctx, HDMI_RX_TMDS_MODE_CTRL_REG, 0x00);
433 	mhl_tx_writeb(ctx, MHL_TX_TMDS_CCTRL, 0x34);
434 	hdmi_writeb(ctx, 0x45, 0x44);
435 	hdmi_writeb(ctx, 0x31, 0x0A);
436 	hdmi_writeb(ctx, HDMI_RX_TMDS0_CCTRL1_REG, 0xC1);
437 
438 	return sii9234_clear_error(ctx);
439 }
440 
441 static int sii9234_mhl_tx_ctl_int(struct sii9234 *ctx)
442 {
443 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL1_REG, 0xD0);
444 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL2_REG, 0xFC);
445 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL4_REG, 0xEB);
446 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL7_REG, 0x0C);
447 
448 	return sii9234_clear_error(ctx);
449 }
450 
451 static int sii9234_reset(struct sii9234 *ctx)
452 {
453 	int ret;
454 
455 	sii9234_clear_error(ctx);
456 
457 	ret = sii9234_power_init(ctx);
458 	if (ret < 0)
459 		return ret;
460 	ret = sii9234_cbus_reset(ctx);
461 	if (ret < 0)
462 		return ret;
463 	ret = sii9234_hdmi_init(ctx);
464 	if (ret < 0)
465 		return ret;
466 	ret = sii9234_mhl_tx_ctl_int(ctx);
467 	if (ret < 0)
468 		return ret;
469 
470 	/* Enable HDCP Compliance safety */
471 	mhl_tx_writeb(ctx, 0x2B, 0x01);
472 	/* CBUS discovery cycle time for each drive and float = 150us */
473 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, 0x04, 0x06);
474 	/* Clear bit 6 (reg_skip_rgnd) */
475 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL2_REG, (1 << 7) /* Reserved */
476 		      | 2 << ATT_THRESH_SHIFT | DEGLITCH_TIME_50MS);
477 	/*
478 	 * Changed from 66 to 65 for 94[1:0] = 01 = 5k reg_cbusmhl_pup_sel
479 	 * 1.8V CBUS VTH & GND threshold
480 	 * to meet CTS 3.3.7.2 spec
481 	 */
482 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL5_REG, 0x77);
483 	cbus_writebm(ctx, CBUS_LINK_CONTROL_2_REG, ~0, MHL_INIT_TIMEOUT);
484 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL6_REG, 0xA0);
485 	/* RGND & single discovery attempt (RGND blocking) */
486 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL6_REG, BLOCK_RGND_INT |
487 		      DVRFLT_SEL | SINGLE_ATT);
488 	/* Use VBUS path of discovery state machine */
489 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL8_REG, 0);
490 	/* 0x92[3] sets the CBUS / ID switch */
491 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, USB_ID_OVR);
492 	/*
493 	 * To allow RGND engine to operate correctly.
494 	 * When moving the chip from D2 to D0 (power up, init regs)
495 	 * the values should be
496 	 * 94[1:0] = 01  reg_cbusmhl_pup_sel[1:0] should be set for 5k
497 	 * 93[7:6] = 10  reg_cbusdisc_pup_sel[1:0] should be
498 	 * set for 10k (default)
499 	 * 93[5:4] = 00  reg_cbusidle_pup_sel[1:0] = open (default)
500 	 */
501 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL3_REG, ~0, 0x86);
502 	/*
503 	 * Change from CC to 8C to match 5K
504 	 * to meet CTS 3.3.72 spec
505 	 */
506 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, ~0, 0x8C);
507 	/* Configure the interrupt as active high */
508 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 0x06);
509 
510 	msleep(25);
511 
512 	/* Release usb_id switch */
513 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, 0,  USB_ID_OVR);
514 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL1_REG, 0x27);
515 
516 	ret = sii9234_clear_error(ctx);
517 	if (ret < 0)
518 		return ret;
519 	ret = sii9234_cbus_init(ctx);
520 	if (ret < 0)
521 		return ret;
522 
523 	/* Enable Auto soft reset on SCDT = 0 */
524 	mhl_tx_writeb(ctx, 0x05, 0x04);
525 	/* HDMI Transcode mode enable */
526 	mhl_tx_writeb(ctx, 0x0D, 0x1C);
527 	mhl_tx_writeb(ctx, MHL_TX_INTR4_ENABLE_REG,
528 		      RGND_READY_MASK | CBUS_LKOUT_MASK
529 			| MHL_DISC_FAIL_MASK | MHL_EST_MASK);
530 	mhl_tx_writeb(ctx, MHL_TX_INTR1_ENABLE_REG, 0x60);
531 
532 	/* This point is very important before measure RGND impedance */
533 	force_usb_id_switch_open(ctx);
534 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, 0, 0xF0);
535 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL5_REG, 0, 0x03);
536 	release_usb_id_switch_open(ctx);
537 
538 	/* Force upstream HPD to 0 when not in MHL mode */
539 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 1 << 5);
540 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, ~0, 1 << 4);
541 
542 	return sii9234_clear_error(ctx);
543 }
544 
545 static int sii9234_goto_d3(struct sii9234 *ctx)
546 {
547 	int ret;
548 
549 	dev_dbg(ctx->dev, "sii9234: detection started d3\n");
550 
551 	ret = sii9234_reset(ctx);
552 	if (ret < 0)
553 		goto exit;
554 
555 	hdmi_writeb(ctx, 0x01, 0x03);
556 	tpi_writebm(ctx, TPI_DPD_REG, 0, 1);
557 	/* I2C above is expected to fail because power goes down */
558 	sii9234_clear_error(ctx);
559 
560 	ctx->state = ST_D3;
561 
562 	return 0;
563  exit:
564 	dev_err(ctx->dev, "%s failed\n", __func__);
565 	return -1;
566 }
567 
568 static int sii9234_hw_on(struct sii9234 *ctx)
569 {
570 	return regulator_bulk_enable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
571 }
572 
573 static void sii9234_hw_off(struct sii9234 *ctx)
574 {
575 	gpiod_set_value(ctx->gpio_reset, 1);
576 	msleep(20);
577 	regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
578 }
579 
580 static void sii9234_hw_reset(struct sii9234 *ctx)
581 {
582 	gpiod_set_value(ctx->gpio_reset, 1);
583 	msleep(20);
584 	gpiod_set_value(ctx->gpio_reset, 0);
585 }
586 
587 static void sii9234_cable_in(struct sii9234 *ctx)
588 {
589 	int ret;
590 
591 	mutex_lock(&ctx->lock);
592 	if (ctx->state != ST_OFF)
593 		goto unlock;
594 	ret = sii9234_hw_on(ctx);
595 	if (ret < 0)
596 		goto unlock;
597 
598 	sii9234_hw_reset(ctx);
599 	sii9234_goto_d3(ctx);
600 	/* To avoid irq storm, when hw is in meta state */
601 	enable_irq(to_i2c_client(ctx->dev)->irq);
602 
603 unlock:
604 	mutex_unlock(&ctx->lock);
605 }
606 
607 static void sii9234_cable_out(struct sii9234 *ctx)
608 {
609 	mutex_lock(&ctx->lock);
610 
611 	if (ctx->state == ST_OFF)
612 		goto unlock;
613 
614 	disable_irq(to_i2c_client(ctx->dev)->irq);
615 	tpi_writeb(ctx, TPI_DPD_REG, 0);
616 	/* Turn on&off hpd festure for only QCT HDMI */
617 	sii9234_hw_off(ctx);
618 
619 	ctx->state = ST_OFF;
620 
621 unlock:
622 	mutex_unlock(&ctx->lock);
623 }
624 
625 static enum sii9234_state sii9234_rgnd_ready_irq(struct sii9234 *ctx)
626 {
627 	int value;
628 
629 	if (ctx->state == ST_D3) {
630 		int ret;
631 
632 		dev_dbg(ctx->dev, "RGND_READY_INT\n");
633 		sii9234_hw_reset(ctx);
634 
635 		ret = sii9234_reset(ctx);
636 		if (ret < 0) {
637 			dev_err(ctx->dev, "sii9234_reset() failed\n");
638 			return ST_FAILURE;
639 		}
640 
641 		return ST_RGND_INIT;
642 	}
643 
644 	/* Got interrupt in inappropriate state */
645 	if (ctx->state != ST_RGND_INIT)
646 		return ST_FAILURE;
647 
648 	value = mhl_tx_readb(ctx, MHL_TX_STAT2_REG);
649 	if (sii9234_clear_error(ctx))
650 		return ST_FAILURE;
651 
652 	if ((value & RGND_INTP_MASK) != RGND_INTP_1K) {
653 		dev_warn(ctx->dev, "RGND is not 1k\n");
654 		return ST_RGND_INIT;
655 	}
656 	dev_dbg(ctx->dev, "RGND 1K!!\n");
657 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, ~0, 0x8C);
658 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL5_REG, 0x77);
659 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, 0x05);
660 	if (sii9234_clear_error(ctx))
661 		return ST_FAILURE;
662 
663 	msleep(T_SRC_VBUS_CBUS_TO_STABLE);
664 	return ST_RGND_1K;
665 }
666 
667 static enum sii9234_state sii9234_mhl_established(struct sii9234 *ctx)
668 {
669 	dev_dbg(ctx->dev, "mhl est interrupt\n");
670 
671 	/* Discovery override */
672 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL1_REG, 0x10);
673 	/* Increase DDC translation layer timer (byte mode) */
674 	cbus_writeb(ctx, 0x07, 0x32);
675 	cbus_writebm(ctx, 0x44, ~0, 1 << 1);
676 	/* Keep the discovery enabled. Need RGND interrupt */
677 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, ~0, 1);
678 	mhl_tx_writeb(ctx, MHL_TX_INTR1_ENABLE_REG,
679 		      RSEN_CHANGE_INT_MASK | HPD_CHANGE_INT_MASK);
680 
681 	if (sii9234_clear_error(ctx))
682 		return ST_FAILURE;
683 
684 	return ST_MHL_ESTABLISHED;
685 }
686 
687 static enum sii9234_state sii9234_hpd_change(struct sii9234 *ctx)
688 {
689 	int value;
690 
691 	value = cbus_readb(ctx, CBUS_MSC_REQ_ABORT_REASON_REG);
692 	if (sii9234_clear_error(ctx))
693 		return ST_FAILURE;
694 
695 	if (value & SET_HPD_DOWNSTREAM) {
696 		/* Downstream HPD High, Enable TMDS */
697 		sii9234_tmds_control(ctx, true);
698 	} else {
699 		/* Downstream HPD Low, Disable TMDS */
700 		sii9234_tmds_control(ctx, false);
701 	}
702 
703 	return ctx->state;
704 }
705 
706 static enum sii9234_state sii9234_rsen_change(struct sii9234 *ctx)
707 {
708 	int value;
709 
710 	/* Work_around code to handle wrong interrupt */
711 	if (ctx->state != ST_RGND_1K) {
712 		dev_err(ctx->dev, "RSEN_HIGH without RGND_1K\n");
713 		return ST_FAILURE;
714 	}
715 	value = mhl_tx_readb(ctx, MHL_TX_SYSSTAT_REG);
716 	if (value < 0)
717 		return ST_FAILURE;
718 
719 	if (value & RSEN_STATUS) {
720 		dev_dbg(ctx->dev, "MHL cable connected.. RSEN High\n");
721 		return ST_RSEN_HIGH;
722 	}
723 	dev_dbg(ctx->dev, "RSEN lost\n");
724 	/*
725 	 * Once RSEN loss is confirmed,we need to check
726 	 * based on cable status and chip power status,whether
727 	 * it is SINK Loss(HDMI cable not connected, TV Off)
728 	 * or MHL cable disconnection
729 	 * TODO: Define the below mhl_disconnection()
730 	 */
731 	msleep(T_SRC_RXSENSE_DEGLITCH);
732 	value = mhl_tx_readb(ctx, MHL_TX_SYSSTAT_REG);
733 	if (value < 0)
734 		return ST_FAILURE;
735 	dev_dbg(ctx->dev, "sys_stat: %x\n", value);
736 
737 	if (value & RSEN_STATUS) {
738 		dev_dbg(ctx->dev, "RSEN recovery\n");
739 		return ST_RSEN_HIGH;
740 	}
741 	dev_dbg(ctx->dev, "RSEN Really LOW\n");
742 	/* To meet CTS 3.3.22.2 spec */
743 	sii9234_tmds_control(ctx, false);
744 	force_usb_id_switch_open(ctx);
745 	release_usb_id_switch_open(ctx);
746 
747 	return ST_FAILURE;
748 }
749 
750 static irqreturn_t sii9234_irq_thread(int irq, void *data)
751 {
752 	struct sii9234 *ctx = data;
753 	int intr1, intr4;
754 	int intr1_en, intr4_en;
755 	int cbus_intr1, cbus_intr2;
756 
757 	dev_dbg(ctx->dev, "%s\n", __func__);
758 
759 	mutex_lock(&ctx->lock);
760 
761 	intr1 = mhl_tx_readb(ctx, MHL_TX_INTR1_REG);
762 	intr4 = mhl_tx_readb(ctx, MHL_TX_INTR4_REG);
763 	intr1_en = mhl_tx_readb(ctx, MHL_TX_INTR1_ENABLE_REG);
764 	intr4_en = mhl_tx_readb(ctx, MHL_TX_INTR4_ENABLE_REG);
765 	cbus_intr1 = cbus_readb(ctx, CBUS_INT_STATUS_1_REG);
766 	cbus_intr2 = cbus_readb(ctx, CBUS_INT_STATUS_2_REG);
767 
768 	if (sii9234_clear_error(ctx))
769 		goto done;
770 
771 	dev_dbg(ctx->dev, "irq %02x/%02x %02x/%02x %02x/%02x\n",
772 		intr1, intr1_en, intr4, intr4_en, cbus_intr1, cbus_intr2);
773 
774 	if (intr4 & RGND_READY_INT)
775 		ctx->state = sii9234_rgnd_ready_irq(ctx);
776 	if (intr1 & RSEN_CHANGE_INT)
777 		ctx->state = sii9234_rsen_change(ctx);
778 	if (intr4 & MHL_EST_INT)
779 		ctx->state = sii9234_mhl_established(ctx);
780 	if (intr1 & HPD_CHANGE_INT)
781 		ctx->state = sii9234_hpd_change(ctx);
782 	if (intr4 & CBUS_LKOUT_INT)
783 		ctx->state = ST_FAILURE;
784 	if (intr4 & MHL_DISC_FAIL_INT)
785 		ctx->state = ST_FAILURE_DISCOVERY;
786 
787  done:
788 	/* Clean interrupt status and pending flags */
789 	mhl_tx_writeb(ctx, MHL_TX_INTR1_REG, intr1);
790 	mhl_tx_writeb(ctx, MHL_TX_INTR4_REG, intr4);
791 	cbus_writeb(ctx, CBUS_MHL_STATUS_REG_0, 0xFF);
792 	cbus_writeb(ctx, CBUS_MHL_STATUS_REG_1, 0xFF);
793 	cbus_writeb(ctx, CBUS_INT_STATUS_1_REG, cbus_intr1);
794 	cbus_writeb(ctx, CBUS_INT_STATUS_2_REG, cbus_intr2);
795 
796 	sii9234_clear_error(ctx);
797 
798 	if (ctx->state == ST_FAILURE) {
799 		dev_dbg(ctx->dev, "try to reset after failure\n");
800 		sii9234_hw_reset(ctx);
801 		sii9234_goto_d3(ctx);
802 	}
803 
804 	if (ctx->state == ST_FAILURE_DISCOVERY) {
805 		dev_err(ctx->dev, "discovery failed, no power for MHL?\n");
806 		tpi_writebm(ctx, TPI_DPD_REG, 0, 1);
807 		ctx->state = ST_D3;
808 	}
809 
810 	mutex_unlock(&ctx->lock);
811 
812 	return IRQ_HANDLED;
813 }
814 
815 static int sii9234_init_resources(struct sii9234 *ctx,
816 				  struct i2c_client *client)
817 {
818 	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
819 	int ret;
820 
821 	if (!ctx->dev->of_node) {
822 		dev_err(ctx->dev, "not DT device\n");
823 		return -ENODEV;
824 	}
825 
826 	ctx->gpio_reset = devm_gpiod_get(ctx->dev, "reset", GPIOD_OUT_LOW);
827 	if (IS_ERR(ctx->gpio_reset)) {
828 		dev_err(ctx->dev, "failed to get reset gpio from DT\n");
829 		return PTR_ERR(ctx->gpio_reset);
830 	}
831 
832 	ctx->supplies[0].supply = "avcc12";
833 	ctx->supplies[1].supply = "avcc33";
834 	ctx->supplies[2].supply = "iovcc18";
835 	ctx->supplies[3].supply = "cvcc12";
836 	ret = devm_regulator_bulk_get(ctx->dev, 4, ctx->supplies);
837 	if (ret) {
838 		dev_err(ctx->dev, "regulator_bulk failed\n");
839 		return ret;
840 	}
841 
842 	ctx->client[I2C_MHL] = client;
843 
844 	ctx->client[I2C_TPI] = i2c_new_dummy(adapter, I2C_TPI_ADDR);
845 	if (!ctx->client[I2C_TPI]) {
846 		dev_err(ctx->dev, "failed to create TPI client\n");
847 		return -ENODEV;
848 	}
849 
850 	ctx->client[I2C_HDMI] = i2c_new_dummy(adapter, I2C_HDMI_ADDR);
851 	if (!ctx->client[I2C_HDMI]) {
852 		dev_err(ctx->dev, "failed to create HDMI RX client\n");
853 		goto fail_tpi;
854 	}
855 
856 	ctx->client[I2C_CBUS] = i2c_new_dummy(adapter, I2C_CBUS_ADDR);
857 	if (!ctx->client[I2C_CBUS]) {
858 		dev_err(ctx->dev, "failed to create CBUS client\n");
859 		goto fail_hdmi;
860 	}
861 
862 	return 0;
863 
864 fail_hdmi:
865 	i2c_unregister_device(ctx->client[I2C_HDMI]);
866 fail_tpi:
867 	i2c_unregister_device(ctx->client[I2C_TPI]);
868 
869 	return -ENODEV;
870 }
871 
872 static void sii9234_deinit_resources(struct sii9234 *ctx)
873 {
874 	i2c_unregister_device(ctx->client[I2C_CBUS]);
875 	i2c_unregister_device(ctx->client[I2C_HDMI]);
876 	i2c_unregister_device(ctx->client[I2C_TPI]);
877 }
878 
879 static inline struct sii9234 *bridge_to_sii9234(struct drm_bridge *bridge)
880 {
881 	return container_of(bridge, struct sii9234, bridge);
882 }
883 
884 static enum drm_mode_status sii9234_mode_valid(struct drm_bridge *bridge,
885 					 const struct drm_display_mode *mode)
886 {
887 	if (mode->clock > MHL1_MAX_CLK)
888 		return MODE_CLOCK_HIGH;
889 
890 	return MODE_OK;
891 }
892 
893 static const struct drm_bridge_funcs sii9234_bridge_funcs = {
894 	.mode_valid = sii9234_mode_valid,
895 };
896 
897 static int sii9234_probe(struct i2c_client *client,
898 			 const struct i2c_device_id *id)
899 {
900 	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
901 	struct sii9234 *ctx;
902 	struct device *dev = &client->dev;
903 	int ret;
904 
905 	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
906 	if (!ctx)
907 		return -ENOMEM;
908 
909 	ctx->dev = dev;
910 	mutex_init(&ctx->lock);
911 
912 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
913 		dev_err(dev, "I2C adapter lacks SMBUS feature\n");
914 		return -EIO;
915 	}
916 
917 	if (!client->irq) {
918 		dev_err(dev, "no irq provided\n");
919 		return -EINVAL;
920 	}
921 
922 	irq_set_status_flags(client->irq, IRQ_NOAUTOEN);
923 	ret = devm_request_threaded_irq(dev, client->irq, NULL,
924 					sii9234_irq_thread,
925 					IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
926 					"sii9234", ctx);
927 	if (ret < 0) {
928 		dev_err(dev, "failed to install IRQ handler\n");
929 		return ret;
930 	}
931 
932 	ret = sii9234_init_resources(ctx, client);
933 	if (ret < 0)
934 		return ret;
935 
936 	i2c_set_clientdata(client, ctx);
937 
938 	ctx->bridge.funcs = &sii9234_bridge_funcs;
939 	ctx->bridge.of_node = dev->of_node;
940 	drm_bridge_add(&ctx->bridge);
941 
942 	sii9234_cable_in(ctx);
943 
944 	return 0;
945 }
946 
947 static int sii9234_remove(struct i2c_client *client)
948 {
949 	struct sii9234 *ctx = i2c_get_clientdata(client);
950 
951 	sii9234_cable_out(ctx);
952 	drm_bridge_remove(&ctx->bridge);
953 	sii9234_deinit_resources(ctx);
954 
955 	return 0;
956 }
957 
958 static const struct of_device_id sii9234_dt_match[] = {
959 	{ .compatible = "sil,sii9234" },
960 	{ },
961 };
962 MODULE_DEVICE_TABLE(of, sii9234_dt_match);
963 
964 static const struct i2c_device_id sii9234_id[] = {
965 	{ "SII9234", 0 },
966 	{ },
967 };
968 MODULE_DEVICE_TABLE(i2c, sii9234_id);
969 
970 static struct i2c_driver sii9234_driver = {
971 	.driver = {
972 		.name	= "sii9234",
973 		.of_match_table = sii9234_dt_match,
974 	},
975 	.probe = sii9234_probe,
976 	.remove = sii9234_remove,
977 	.id_table = sii9234_id,
978 };
979 
980 module_i2c_driver(sii9234_driver);
981 MODULE_LICENSE("GPL");
982