xref: /openbmc/linux/drivers/gpu/drm/bridge/sii9234.c (revision bc05aa6e)
1 /*
2  * Copyright (C) 2017 Samsung Electronics
3  *
4  * Authors:
5  *    Tomasz Stanislawski <t.stanislaws@samsung.com>
6  *    Maciej Purski <m.purski@samsung.com>
7  *
8  * Based on sii9234 driver created by:
9  *    Adam Hampson <ahampson@sta.samsung.com>
10  *    Erik Gilling <konkers@android.com>
11  *    Shankar Bandal <shankar.b@samsung.com>
12  *    Dharam Kumar <dharam.kr@samsung.com>
13  *
14  * This program is free software; you can redistribute it and/or modify
15  * it under the terms of the GNU General Public License as published by
16  * the Free Software Foundation; either version 2 of the License, or
17  * (at your option) any later version.
18  *
19  * This program is distributed in the hope that it will be useful,
20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
22  * GNU General Public License for more details.
23  *
24  * You should have received a copy of the GNU General Public License
25  * along with this program
26  *
27  */
28 #include <drm/bridge/mhl.h>
29 #include <drm/drm_crtc.h>
30 #include <drm/drm_edid.h>
31 
32 #include <linux/delay.h>
33 #include <linux/err.h>
34 #include <linux/gpio/consumer.h>
35 #include <linux/i2c.h>
36 #include <linux/interrupt.h>
37 #include <linux/irq.h>
38 #include <linux/kernel.h>
39 #include <linux/module.h>
40 #include <linux/mutex.h>
41 #include <linux/regulator/consumer.h>
42 #include <linux/slab.h>
43 
44 #define CBUS_DEVCAP_OFFSET		0x80
45 
46 #define SII9234_MHL_VERSION		0x11
47 #define SII9234_SCRATCHPAD_SIZE		0x10
48 #define SII9234_INT_STAT_SIZE		0x33
49 
50 #define BIT_TMDS_CCTRL_TMDS_OE		BIT(4)
51 #define MHL_HPD_OUT_OVR_EN		BIT(4)
52 #define MHL_HPD_OUT_OVR_VAL		BIT(5)
53 #define MHL_INIT_TIMEOUT		0x0C
54 
55 /* MHL Tx registers and bits */
56 #define MHL_TX_SRST			0x05
57 #define MHL_TX_SYSSTAT_REG		0x09
58 #define MHL_TX_INTR1_REG		0x71
59 #define MHL_TX_INTR4_REG		0x74
60 #define MHL_TX_INTR1_ENABLE_REG		0x75
61 #define MHL_TX_INTR4_ENABLE_REG		0x78
62 #define MHL_TX_INT_CTRL_REG		0x79
63 #define MHL_TX_TMDS_CCTRL		0x80
64 #define MHL_TX_DISC_CTRL1_REG		0x90
65 #define MHL_TX_DISC_CTRL2_REG		0x91
66 #define MHL_TX_DISC_CTRL3_REG		0x92
67 #define MHL_TX_DISC_CTRL4_REG		0x93
68 #define MHL_TX_DISC_CTRL5_REG		0x94
69 #define MHL_TX_DISC_CTRL6_REG		0x95
70 #define MHL_TX_DISC_CTRL7_REG		0x96
71 #define MHL_TX_DISC_CTRL8_REG		0x97
72 #define MHL_TX_STAT2_REG		0x99
73 #define MHL_TX_MHLTX_CTL1_REG		0xA0
74 #define MHL_TX_MHLTX_CTL2_REG		0xA1
75 #define MHL_TX_MHLTX_CTL4_REG		0xA3
76 #define MHL_TX_MHLTX_CTL6_REG		0xA5
77 #define MHL_TX_MHLTX_CTL7_REG		0xA6
78 
79 #define RSEN_STATUS			BIT(2)
80 #define HPD_CHANGE_INT			BIT(6)
81 #define RSEN_CHANGE_INT			BIT(5)
82 #define RGND_READY_INT			BIT(6)
83 #define VBUS_LOW_INT			BIT(5)
84 #define CBUS_LKOUT_INT			BIT(4)
85 #define MHL_DISC_FAIL_INT		BIT(3)
86 #define MHL_EST_INT			BIT(2)
87 #define HPD_CHANGE_INT_MASK		BIT(6)
88 #define RSEN_CHANGE_INT_MASK		BIT(5)
89 
90 #define RGND_READY_MASK			BIT(6)
91 #define CBUS_LKOUT_MASK			BIT(4)
92 #define MHL_DISC_FAIL_MASK		BIT(3)
93 #define MHL_EST_MASK			BIT(2)
94 
95 #define SKIP_GND			BIT(6)
96 
97 #define ATT_THRESH_SHIFT		0x04
98 #define ATT_THRESH_MASK			(0x03 << ATT_THRESH_SHIFT)
99 #define USB_D_OEN			BIT(3)
100 #define DEGLITCH_TIME_MASK		0x07
101 #define DEGLITCH_TIME_2MS		0
102 #define DEGLITCH_TIME_4MS		1
103 #define DEGLITCH_TIME_8MS		2
104 #define DEGLITCH_TIME_16MS		3
105 #define DEGLITCH_TIME_40MS		4
106 #define DEGLITCH_TIME_50MS		5
107 #define DEGLITCH_TIME_60MS		6
108 #define DEGLITCH_TIME_128MS		7
109 
110 #define USB_D_OVR			BIT(7)
111 #define USB_ID_OVR			BIT(6)
112 #define DVRFLT_SEL			BIT(5)
113 #define BLOCK_RGND_INT			BIT(4)
114 #define SKIP_DEG			BIT(3)
115 #define CI2CA_POL			BIT(2)
116 #define CI2CA_WKUP			BIT(1)
117 #define SINGLE_ATT			BIT(0)
118 
119 #define USB_D_ODN			BIT(5)
120 #define VBUS_CHECK			BIT(2)
121 #define RGND_INTP_MASK			0x03
122 #define RGND_INTP_OPEN			0
123 #define RGND_INTP_2K			1
124 #define RGND_INTP_1K			2
125 #define RGND_INTP_SHORT			3
126 
127 /* HDMI registers */
128 #define HDMI_RX_TMDS0_CCTRL1_REG	0x10
129 #define HDMI_RX_TMDS_CLK_EN_REG		0x11
130 #define HDMI_RX_TMDS_CH_EN_REG		0x12
131 #define HDMI_RX_PLL_CALREFSEL_REG	0x17
132 #define HDMI_RX_PLL_VCOCAL_REG		0x1A
133 #define HDMI_RX_EQ_DATA0_REG		0x22
134 #define HDMI_RX_EQ_DATA1_REG		0x23
135 #define HDMI_RX_EQ_DATA2_REG		0x24
136 #define HDMI_RX_EQ_DATA3_REG		0x25
137 #define HDMI_RX_EQ_DATA4_REG		0x26
138 #define HDMI_RX_TMDS_ZONE_CTRL_REG	0x4C
139 #define HDMI_RX_TMDS_MODE_CTRL_REG	0x4D
140 
141 /* CBUS registers */
142 #define CBUS_INT_STATUS_1_REG		0x08
143 #define CBUS_INTR1_ENABLE_REG		0x09
144 #define CBUS_MSC_REQ_ABORT_REASON_REG	0x0D
145 #define CBUS_INT_STATUS_2_REG		0x1E
146 #define CBUS_INTR2_ENABLE_REG		0x1F
147 #define CBUS_LINK_CONTROL_2_REG		0x31
148 #define CBUS_MHL_STATUS_REG_0		0xB0
149 #define CBUS_MHL_STATUS_REG_1		0xB1
150 
151 #define BIT_CBUS_RESET			BIT(3)
152 #define SET_HPD_DOWNSTREAM		BIT(6)
153 
154 /* TPI registers */
155 #define TPI_DPD_REG			0x3D
156 
157 /* Timeouts in msec */
158 #define T_SRC_VBUS_CBUS_TO_STABLE	200
159 #define T_SRC_CBUS_FLOAT		100
160 #define T_SRC_CBUS_DEGLITCH		2
161 #define T_SRC_RXSENSE_DEGLITCH		110
162 
163 #define MHL1_MAX_CLK			75000 /* in kHz */
164 
165 #define I2C_TPI_ADDR			0x3D
166 #define I2C_HDMI_ADDR			0x49
167 #define I2C_CBUS_ADDR			0x64
168 
169 enum sii9234_state {
170 	ST_OFF,
171 	ST_D3,
172 	ST_RGND_INIT,
173 	ST_RGND_1K,
174 	ST_RSEN_HIGH,
175 	ST_MHL_ESTABLISHED,
176 	ST_FAILURE_DISCOVERY,
177 	ST_FAILURE,
178 };
179 
180 struct sii9234 {
181 	struct i2c_client *client[4];
182 	struct drm_bridge bridge;
183 	struct device *dev;
184 	struct gpio_desc *gpio_reset;
185 	int i2c_error;
186 	struct regulator_bulk_data supplies[4];
187 
188 	struct mutex lock; /* Protects fields below and device registers */
189 	enum sii9234_state state;
190 };
191 
192 enum sii9234_client_id {
193 	I2C_MHL,
194 	I2C_TPI,
195 	I2C_HDMI,
196 	I2C_CBUS,
197 };
198 
199 static const char * const sii9234_client_name[] = {
200 	[I2C_MHL] = "MHL",
201 	[I2C_TPI] = "TPI",
202 	[I2C_HDMI] = "HDMI",
203 	[I2C_CBUS] = "CBUS",
204 };
205 
206 static int sii9234_writeb(struct sii9234 *ctx, int id, int offset,
207 			  int value)
208 {
209 	int ret;
210 	struct i2c_client *client = ctx->client[id];
211 
212 	if (ctx->i2c_error)
213 		return ctx->i2c_error;
214 
215 	ret = i2c_smbus_write_byte_data(client, offset, value);
216 	if (ret < 0)
217 		dev_err(ctx->dev, "writeb: %4s[0x%02x] <- 0x%02x\n",
218 			sii9234_client_name[id], offset, value);
219 	ctx->i2c_error = ret;
220 
221 	return ret;
222 }
223 
224 static int sii9234_writebm(struct sii9234 *ctx, int id, int offset,
225 			   int value, int mask)
226 {
227 	int ret;
228 	struct i2c_client *client = ctx->client[id];
229 
230 	if (ctx->i2c_error)
231 		return ctx->i2c_error;
232 
233 	ret = i2c_smbus_write_byte(client, offset);
234 	if (ret < 0) {
235 		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
236 			sii9234_client_name[id], offset, value);
237 		ctx->i2c_error = ret;
238 		return ret;
239 	}
240 
241 	ret = i2c_smbus_read_byte(client);
242 	if (ret < 0) {
243 		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
244 			sii9234_client_name[id], offset, value);
245 		ctx->i2c_error = ret;
246 		return ret;
247 	}
248 
249 	value = (value & mask) | (ret & ~mask);
250 
251 	ret = i2c_smbus_write_byte_data(client, offset, value);
252 	if (ret < 0) {
253 		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
254 			sii9234_client_name[id], offset, value);
255 		ctx->i2c_error = ret;
256 	}
257 
258 	return ret;
259 }
260 
261 static int sii9234_readb(struct sii9234 *ctx, int id, int offset)
262 {
263 	int ret;
264 	struct i2c_client *client = ctx->client[id];
265 
266 	if (ctx->i2c_error)
267 		return ctx->i2c_error;
268 
269 	ret = i2c_smbus_write_byte(client, offset);
270 	if (ret < 0) {
271 		dev_err(ctx->dev, "readb: %4s[0x%02x]\n",
272 			sii9234_client_name[id], offset);
273 		ctx->i2c_error = ret;
274 		return ret;
275 	}
276 
277 	ret = i2c_smbus_read_byte(client);
278 	if (ret < 0) {
279 		dev_err(ctx->dev, "readb: %4s[0x%02x]\n",
280 			sii9234_client_name[id], offset);
281 		ctx->i2c_error = ret;
282 	}
283 
284 	return ret;
285 }
286 
287 static int sii9234_clear_error(struct sii9234 *ctx)
288 {
289 	int ret = ctx->i2c_error;
290 
291 	ctx->i2c_error = 0;
292 
293 	return ret;
294 }
295 
296 #define mhl_tx_writeb(sii9234, offset, value) \
297 	sii9234_writeb(sii9234, I2C_MHL, offset, value)
298 #define mhl_tx_writebm(sii9234, offset, value, mask) \
299 	sii9234_writebm(sii9234, I2C_MHL, offset, value, mask)
300 #define mhl_tx_readb(sii9234, offset) \
301 	sii9234_readb(sii9234, I2C_MHL, offset)
302 #define cbus_writeb(sii9234, offset, value) \
303 	sii9234_writeb(sii9234, I2C_CBUS, offset, value)
304 #define cbus_writebm(sii9234, offset, value, mask) \
305 	sii9234_writebm(sii9234, I2C_CBUS, offset, value, mask)
306 #define cbus_readb(sii9234, offset) \
307 	sii9234_readb(sii9234, I2C_CBUS, offset)
308 #define hdmi_writeb(sii9234, offset, value) \
309 	sii9234_writeb(sii9234, I2C_HDMI, offset, value)
310 #define hdmi_writebm(sii9234, offset, value, mask) \
311 	sii9234_writebm(sii9234, I2C_HDMI, offset, value, mask)
312 #define hdmi_readb(sii9234, offset) \
313 	sii9234_readb(sii9234, I2C_HDMI, offset)
314 #define tpi_writeb(sii9234, offset, value) \
315 	sii9234_writeb(sii9234, I2C_TPI, offset, value)
316 #define tpi_writebm(sii9234, offset, value, mask) \
317 	sii9234_writebm(sii9234, I2C_TPI, offset, value, mask)
318 #define tpi_readb(sii9234, offset) \
319 	sii9234_readb(sii9234, I2C_TPI, offset)
320 
321 static u8 sii9234_tmds_control(struct sii9234 *ctx, bool enable)
322 {
323 	mhl_tx_writebm(ctx, MHL_TX_TMDS_CCTRL, enable ? ~0 : 0,
324 		       BIT_TMDS_CCTRL_TMDS_OE);
325 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, enable ? ~0 : 0,
326 		       MHL_HPD_OUT_OVR_EN | MHL_HPD_OUT_OVR_VAL);
327 	return sii9234_clear_error(ctx);
328 }
329 
330 static int sii9234_cbus_reset(struct sii9234 *ctx)
331 {
332 	int i;
333 
334 	mhl_tx_writebm(ctx, MHL_TX_SRST, ~0, BIT_CBUS_RESET);
335 	msleep(T_SRC_CBUS_DEGLITCH);
336 	mhl_tx_writebm(ctx, MHL_TX_SRST, 0, BIT_CBUS_RESET);
337 
338 	for (i = 0; i < 4; i++) {
339 		/*
340 		 * Enable WRITE_STAT interrupt for writes to all
341 		 * 4 MSC Status registers.
342 		 */
343 		cbus_writeb(ctx, 0xE0 + i, 0xF2);
344 		/*
345 		 * Enable SET_INT interrupt for writes to all
346 		 * 4 MSC Interrupt registers.
347 		 */
348 		cbus_writeb(ctx, 0xF0 + i, 0xF2);
349 	}
350 
351 	return sii9234_clear_error(ctx);
352 }
353 
354 /* Require to chek mhl imformation of samsung in cbus_init_register */
355 static int sii9234_cbus_init(struct sii9234 *ctx)
356 {
357 	cbus_writeb(ctx, 0x07, 0xF2);
358 	cbus_writeb(ctx, 0x40, 0x03);
359 	cbus_writeb(ctx, 0x42, 0x06);
360 	cbus_writeb(ctx, 0x36, 0x0C);
361 	cbus_writeb(ctx, 0x3D, 0xFD);
362 	cbus_writeb(ctx, 0x1C, 0x01);
363 	cbus_writeb(ctx, 0x1D, 0x0F);
364 	cbus_writeb(ctx, 0x44, 0x02);
365 	/* Setup our devcap */
366 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_DEV_STATE, 0x00);
367 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_MHL_VERSION,
368 		    SII9234_MHL_VERSION);
369 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_CAT,
370 		    MHL_DCAP_CAT_SOURCE);
371 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_ADOPTER_ID_H, 0x01);
372 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_ADOPTER_ID_L, 0x41);
373 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_VID_LINK_MODE,
374 		    MHL_DCAP_VID_LINK_RGB444 | MHL_DCAP_VID_LINK_YCBCR444);
375 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_VIDEO_TYPE,
376 		    MHL_DCAP_VT_GRAPHICS);
377 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_LOG_DEV_MAP,
378 		    MHL_DCAP_LD_GUI);
379 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_BANDWIDTH, 0x0F);
380 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_FEATURE_FLAG,
381 		    MHL_DCAP_FEATURE_RCP_SUPPORT | MHL_DCAP_FEATURE_RAP_SUPPORT
382 			| MHL_DCAP_FEATURE_SP_SUPPORT);
383 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_DEVICE_ID_H, 0x0);
384 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_DEVICE_ID_L, 0x0);
385 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_SCRATCHPAD_SIZE,
386 		    SII9234_SCRATCHPAD_SIZE);
387 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_INT_STAT_SIZE,
388 		    SII9234_INT_STAT_SIZE);
389 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_RESERVED, 0);
390 	cbus_writebm(ctx, 0x31, 0x0C, 0x0C);
391 	cbus_writeb(ctx, 0x30, 0x01);
392 	cbus_writebm(ctx, 0x3C, 0x30, 0x38);
393 	cbus_writebm(ctx, 0x22, 0x0D, 0x0F);
394 	cbus_writebm(ctx, 0x2E, 0x15, 0x15);
395 	cbus_writeb(ctx, CBUS_INTR1_ENABLE_REG, 0);
396 	cbus_writeb(ctx, CBUS_INTR2_ENABLE_REG, 0);
397 
398 	return sii9234_clear_error(ctx);
399 }
400 
401 static void force_usb_id_switch_open(struct sii9234 *ctx)
402 {
403 	/* Disable CBUS discovery */
404 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, 0, 0x01);
405 	/* Force USB ID switch to open */
406 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, USB_ID_OVR);
407 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL3_REG, ~0, 0x86);
408 	/* Force upstream HPD to 0 when not in MHL mode. */
409 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 0x30);
410 }
411 
412 static void release_usb_id_switch_open(struct sii9234 *ctx)
413 {
414 	msleep(T_SRC_CBUS_FLOAT);
415 	/* Clear USB ID switch to open */
416 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, 0, USB_ID_OVR);
417 	/* Enable CBUS discovery */
418 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, ~0, 0x01);
419 }
420 
421 static int sii9234_power_init(struct sii9234 *ctx)
422 {
423 	/* Force the SiI9234 into the D0 state. */
424 	tpi_writeb(ctx, TPI_DPD_REG, 0x3F);
425 	/* Enable TxPLL Clock */
426 	hdmi_writeb(ctx, HDMI_RX_TMDS_CLK_EN_REG, 0x01);
427 	/* Enable Tx Clock Path & Equalizer */
428 	hdmi_writeb(ctx, HDMI_RX_TMDS_CH_EN_REG, 0x15);
429 	/* Power Up TMDS */
430 	mhl_tx_writeb(ctx, 0x08, 0x35);
431 	return sii9234_clear_error(ctx);
432 }
433 
434 static int sii9234_hdmi_init(struct sii9234 *ctx)
435 {
436 	hdmi_writeb(ctx, HDMI_RX_TMDS0_CCTRL1_REG, 0xC1);
437 	hdmi_writeb(ctx, HDMI_RX_PLL_CALREFSEL_REG, 0x03);
438 	hdmi_writeb(ctx, HDMI_RX_PLL_VCOCAL_REG, 0x20);
439 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA0_REG, 0x8A);
440 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA1_REG, 0x6A);
441 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA2_REG, 0xAA);
442 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA3_REG, 0xCA);
443 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA4_REG, 0xEA);
444 	hdmi_writeb(ctx, HDMI_RX_TMDS_ZONE_CTRL_REG, 0xA0);
445 	hdmi_writeb(ctx, HDMI_RX_TMDS_MODE_CTRL_REG, 0x00);
446 	mhl_tx_writeb(ctx, MHL_TX_TMDS_CCTRL, 0x34);
447 	hdmi_writeb(ctx, 0x45, 0x44);
448 	hdmi_writeb(ctx, 0x31, 0x0A);
449 	hdmi_writeb(ctx, HDMI_RX_TMDS0_CCTRL1_REG, 0xC1);
450 
451 	return sii9234_clear_error(ctx);
452 }
453 
454 static int sii9234_mhl_tx_ctl_int(struct sii9234 *ctx)
455 {
456 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL1_REG, 0xD0);
457 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL2_REG, 0xFC);
458 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL4_REG, 0xEB);
459 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL7_REG, 0x0C);
460 
461 	return sii9234_clear_error(ctx);
462 }
463 
464 static int sii9234_reset(struct sii9234 *ctx)
465 {
466 	int ret;
467 
468 	sii9234_clear_error(ctx);
469 
470 	ret = sii9234_power_init(ctx);
471 	if (ret < 0)
472 		return ret;
473 	ret = sii9234_cbus_reset(ctx);
474 	if (ret < 0)
475 		return ret;
476 	ret = sii9234_hdmi_init(ctx);
477 	if (ret < 0)
478 		return ret;
479 	ret = sii9234_mhl_tx_ctl_int(ctx);
480 	if (ret < 0)
481 		return ret;
482 
483 	/* Enable HDCP Compliance safety */
484 	mhl_tx_writeb(ctx, 0x2B, 0x01);
485 	/* CBUS discovery cycle time for each drive and float = 150us */
486 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, 0x04, 0x06);
487 	/* Clear bit 6 (reg_skip_rgnd) */
488 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL2_REG, (1 << 7) /* Reserved */
489 		      | 2 << ATT_THRESH_SHIFT | DEGLITCH_TIME_50MS);
490 	/*
491 	 * Changed from 66 to 65 for 94[1:0] = 01 = 5k reg_cbusmhl_pup_sel
492 	 * 1.8V CBUS VTH & GND threshold
493 	 * to meet CTS 3.3.7.2 spec
494 	 */
495 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL5_REG, 0x77);
496 	cbus_writebm(ctx, CBUS_LINK_CONTROL_2_REG, ~0, MHL_INIT_TIMEOUT);
497 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL6_REG, 0xA0);
498 	/* RGND & single discovery attempt (RGND blocking) */
499 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL6_REG, BLOCK_RGND_INT |
500 		      DVRFLT_SEL | SINGLE_ATT);
501 	/* Use VBUS path of discovery state machine */
502 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL8_REG, 0);
503 	/* 0x92[3] sets the CBUS / ID switch */
504 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, USB_ID_OVR);
505 	/*
506 	 * To allow RGND engine to operate correctly.
507 	 * When moving the chip from D2 to D0 (power up, init regs)
508 	 * the values should be
509 	 * 94[1:0] = 01  reg_cbusmhl_pup_sel[1:0] should be set for 5k
510 	 * 93[7:6] = 10  reg_cbusdisc_pup_sel[1:0] should be
511 	 * set for 10k (default)
512 	 * 93[5:4] = 00  reg_cbusidle_pup_sel[1:0] = open (default)
513 	 */
514 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL3_REG, ~0, 0x86);
515 	/*
516 	 * Change from CC to 8C to match 5K
517 	 * to meet CTS 3.3.72 spec
518 	 */
519 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, ~0, 0x8C);
520 	/* Configure the interrupt as active high */
521 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 0x06);
522 
523 	msleep(25);
524 
525 	/* Release usb_id switch */
526 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, 0,  USB_ID_OVR);
527 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL1_REG, 0x27);
528 
529 	ret = sii9234_clear_error(ctx);
530 	if (ret < 0)
531 		return ret;
532 	ret = sii9234_cbus_init(ctx);
533 	if (ret < 0)
534 		return ret;
535 
536 	/* Enable Auto soft reset on SCDT = 0 */
537 	mhl_tx_writeb(ctx, 0x05, 0x04);
538 	/* HDMI Transcode mode enable */
539 	mhl_tx_writeb(ctx, 0x0D, 0x1C);
540 	mhl_tx_writeb(ctx, MHL_TX_INTR4_ENABLE_REG,
541 		      RGND_READY_MASK | CBUS_LKOUT_MASK
542 			| MHL_DISC_FAIL_MASK | MHL_EST_MASK);
543 	mhl_tx_writeb(ctx, MHL_TX_INTR1_ENABLE_REG, 0x60);
544 
545 	/* This point is very important before measure RGND impedance */
546 	force_usb_id_switch_open(ctx);
547 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, 0, 0xF0);
548 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL5_REG, 0, 0x03);
549 	release_usb_id_switch_open(ctx);
550 
551 	/* Force upstream HPD to 0 when not in MHL mode */
552 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 1 << 5);
553 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, ~0, 1 << 4);
554 
555 	return sii9234_clear_error(ctx);
556 }
557 
558 static int sii9234_goto_d3(struct sii9234 *ctx)
559 {
560 	int ret;
561 
562 	dev_dbg(ctx->dev, "sii9234: detection started d3\n");
563 
564 	ret = sii9234_reset(ctx);
565 	if (ret < 0)
566 		goto exit;
567 
568 	hdmi_writeb(ctx, 0x01, 0x03);
569 	tpi_writebm(ctx, TPI_DPD_REG, 0, 1);
570 	/* I2C above is expected to fail because power goes down */
571 	sii9234_clear_error(ctx);
572 
573 	ctx->state = ST_D3;
574 
575 	return 0;
576  exit:
577 	dev_err(ctx->dev, "%s failed\n", __func__);
578 	return -1;
579 }
580 
581 static int sii9234_hw_on(struct sii9234 *ctx)
582 {
583 	return regulator_bulk_enable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
584 }
585 
586 static void sii9234_hw_off(struct sii9234 *ctx)
587 {
588 	gpiod_set_value(ctx->gpio_reset, 1);
589 	msleep(20);
590 	regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
591 }
592 
593 static void sii9234_hw_reset(struct sii9234 *ctx)
594 {
595 	gpiod_set_value(ctx->gpio_reset, 1);
596 	msleep(20);
597 	gpiod_set_value(ctx->gpio_reset, 0);
598 }
599 
600 static void sii9234_cable_in(struct sii9234 *ctx)
601 {
602 	int ret;
603 
604 	mutex_lock(&ctx->lock);
605 	if (ctx->state != ST_OFF)
606 		goto unlock;
607 	ret = sii9234_hw_on(ctx);
608 	if (ret < 0)
609 		goto unlock;
610 
611 	sii9234_hw_reset(ctx);
612 	sii9234_goto_d3(ctx);
613 	/* To avoid irq storm, when hw is in meta state */
614 	enable_irq(to_i2c_client(ctx->dev)->irq);
615 
616 unlock:
617 	mutex_unlock(&ctx->lock);
618 }
619 
620 static void sii9234_cable_out(struct sii9234 *ctx)
621 {
622 	mutex_lock(&ctx->lock);
623 
624 	if (ctx->state == ST_OFF)
625 		goto unlock;
626 
627 	disable_irq(to_i2c_client(ctx->dev)->irq);
628 	tpi_writeb(ctx, TPI_DPD_REG, 0);
629 	/* Turn on&off hpd festure for only QCT HDMI */
630 	sii9234_hw_off(ctx);
631 
632 	ctx->state = ST_OFF;
633 
634 unlock:
635 	mutex_unlock(&ctx->lock);
636 }
637 
638 static enum sii9234_state sii9234_rgnd_ready_irq(struct sii9234 *ctx)
639 {
640 	int value;
641 
642 	if (ctx->state == ST_D3) {
643 		int ret;
644 
645 		dev_dbg(ctx->dev, "RGND_READY_INT\n");
646 		sii9234_hw_reset(ctx);
647 
648 		ret = sii9234_reset(ctx);
649 		if (ret < 0) {
650 			dev_err(ctx->dev, "sii9234_reset() failed\n");
651 			return ST_FAILURE;
652 		}
653 
654 		return ST_RGND_INIT;
655 	}
656 
657 	/* Got interrupt in inappropriate state */
658 	if (ctx->state != ST_RGND_INIT)
659 		return ST_FAILURE;
660 
661 	value = mhl_tx_readb(ctx, MHL_TX_STAT2_REG);
662 	if (sii9234_clear_error(ctx))
663 		return ST_FAILURE;
664 
665 	if ((value & RGND_INTP_MASK) != RGND_INTP_1K) {
666 		dev_warn(ctx->dev, "RGND is not 1k\n");
667 		return ST_RGND_INIT;
668 	}
669 	dev_dbg(ctx->dev, "RGND 1K!!\n");
670 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, ~0, 0x8C);
671 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL5_REG, 0x77);
672 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, 0x05);
673 	if (sii9234_clear_error(ctx))
674 		return ST_FAILURE;
675 
676 	msleep(T_SRC_VBUS_CBUS_TO_STABLE);
677 	return ST_RGND_1K;
678 }
679 
680 static enum sii9234_state sii9234_mhl_established(struct sii9234 *ctx)
681 {
682 	dev_dbg(ctx->dev, "mhl est interrupt\n");
683 
684 	/* Discovery override */
685 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL1_REG, 0x10);
686 	/* Increase DDC translation layer timer (byte mode) */
687 	cbus_writeb(ctx, 0x07, 0x32);
688 	cbus_writebm(ctx, 0x44, ~0, 1 << 1);
689 	/* Keep the discovery enabled. Need RGND interrupt */
690 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, ~0, 1);
691 	mhl_tx_writeb(ctx, MHL_TX_INTR1_ENABLE_REG,
692 		      RSEN_CHANGE_INT_MASK | HPD_CHANGE_INT_MASK);
693 
694 	if (sii9234_clear_error(ctx))
695 		return ST_FAILURE;
696 
697 	return ST_MHL_ESTABLISHED;
698 }
699 
700 static enum sii9234_state sii9234_hpd_change(struct sii9234 *ctx)
701 {
702 	int value;
703 
704 	value = cbus_readb(ctx, CBUS_MSC_REQ_ABORT_REASON_REG);
705 	if (sii9234_clear_error(ctx))
706 		return ST_FAILURE;
707 
708 	if (value & SET_HPD_DOWNSTREAM) {
709 		/* Downstream HPD High, Enable TMDS */
710 		sii9234_tmds_control(ctx, true);
711 	} else {
712 		/* Downstream HPD Low, Disable TMDS */
713 		sii9234_tmds_control(ctx, false);
714 	}
715 
716 	return ctx->state;
717 }
718 
719 static enum sii9234_state sii9234_rsen_change(struct sii9234 *ctx)
720 {
721 	int value;
722 
723 	/* Work_around code to handle wrong interrupt */
724 	if (ctx->state != ST_RGND_1K) {
725 		dev_err(ctx->dev, "RSEN_HIGH without RGND_1K\n");
726 		return ST_FAILURE;
727 	}
728 	value = mhl_tx_readb(ctx, MHL_TX_SYSSTAT_REG);
729 	if (value < 0)
730 		return ST_FAILURE;
731 
732 	if (value & RSEN_STATUS) {
733 		dev_dbg(ctx->dev, "MHL cable connected.. RSEN High\n");
734 		return ST_RSEN_HIGH;
735 	}
736 	dev_dbg(ctx->dev, "RSEN lost\n");
737 	/*
738 	 * Once RSEN loss is confirmed,we need to check
739 	 * based on cable status and chip power status,whether
740 	 * it is SINK Loss(HDMI cable not connected, TV Off)
741 	 * or MHL cable disconnection
742 	 * TODO: Define the below mhl_disconnection()
743 	 */
744 	msleep(T_SRC_RXSENSE_DEGLITCH);
745 	value = mhl_tx_readb(ctx, MHL_TX_SYSSTAT_REG);
746 	if (value < 0)
747 		return ST_FAILURE;
748 	dev_dbg(ctx->dev, "sys_stat: %x\n", value);
749 
750 	if (value & RSEN_STATUS) {
751 		dev_dbg(ctx->dev, "RSEN recovery\n");
752 		return ST_RSEN_HIGH;
753 	}
754 	dev_dbg(ctx->dev, "RSEN Really LOW\n");
755 	/* To meet CTS 3.3.22.2 spec */
756 	sii9234_tmds_control(ctx, false);
757 	force_usb_id_switch_open(ctx);
758 	release_usb_id_switch_open(ctx);
759 
760 	return ST_FAILURE;
761 }
762 
763 static irqreturn_t sii9234_irq_thread(int irq, void *data)
764 {
765 	struct sii9234 *ctx = data;
766 	int intr1, intr4;
767 	int intr1_en, intr4_en;
768 	int cbus_intr1, cbus_intr2;
769 
770 	dev_dbg(ctx->dev, "%s\n", __func__);
771 
772 	mutex_lock(&ctx->lock);
773 
774 	intr1 = mhl_tx_readb(ctx, MHL_TX_INTR1_REG);
775 	intr4 = mhl_tx_readb(ctx, MHL_TX_INTR4_REG);
776 	intr1_en = mhl_tx_readb(ctx, MHL_TX_INTR1_ENABLE_REG);
777 	intr4_en = mhl_tx_readb(ctx, MHL_TX_INTR4_ENABLE_REG);
778 	cbus_intr1 = cbus_readb(ctx, CBUS_INT_STATUS_1_REG);
779 	cbus_intr2 = cbus_readb(ctx, CBUS_INT_STATUS_2_REG);
780 
781 	if (sii9234_clear_error(ctx))
782 		goto done;
783 
784 	dev_dbg(ctx->dev, "irq %02x/%02x %02x/%02x %02x/%02x\n",
785 		intr1, intr1_en, intr4, intr4_en, cbus_intr1, cbus_intr2);
786 
787 	if (intr4 & RGND_READY_INT)
788 		ctx->state = sii9234_rgnd_ready_irq(ctx);
789 	if (intr1 & RSEN_CHANGE_INT)
790 		ctx->state = sii9234_rsen_change(ctx);
791 	if (intr4 & MHL_EST_INT)
792 		ctx->state = sii9234_mhl_established(ctx);
793 	if (intr1 & HPD_CHANGE_INT)
794 		ctx->state = sii9234_hpd_change(ctx);
795 	if (intr4 & CBUS_LKOUT_INT)
796 		ctx->state = ST_FAILURE;
797 	if (intr4 & MHL_DISC_FAIL_INT)
798 		ctx->state = ST_FAILURE_DISCOVERY;
799 
800  done:
801 	/* Clean interrupt status and pending flags */
802 	mhl_tx_writeb(ctx, MHL_TX_INTR1_REG, intr1);
803 	mhl_tx_writeb(ctx, MHL_TX_INTR4_REG, intr4);
804 	cbus_writeb(ctx, CBUS_MHL_STATUS_REG_0, 0xFF);
805 	cbus_writeb(ctx, CBUS_MHL_STATUS_REG_1, 0xFF);
806 	cbus_writeb(ctx, CBUS_INT_STATUS_1_REG, cbus_intr1);
807 	cbus_writeb(ctx, CBUS_INT_STATUS_2_REG, cbus_intr2);
808 
809 	sii9234_clear_error(ctx);
810 
811 	if (ctx->state == ST_FAILURE) {
812 		dev_dbg(ctx->dev, "try to reset after failure\n");
813 		sii9234_hw_reset(ctx);
814 		sii9234_goto_d3(ctx);
815 	}
816 
817 	if (ctx->state == ST_FAILURE_DISCOVERY) {
818 		dev_err(ctx->dev, "discovery failed, no power for MHL?\n");
819 		tpi_writebm(ctx, TPI_DPD_REG, 0, 1);
820 		ctx->state = ST_D3;
821 	}
822 
823 	mutex_unlock(&ctx->lock);
824 
825 	return IRQ_HANDLED;
826 }
827 
828 static int sii9234_init_resources(struct sii9234 *ctx,
829 				  struct i2c_client *client)
830 {
831 	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
832 	int ret;
833 
834 	if (!ctx->dev->of_node) {
835 		dev_err(ctx->dev, "not DT device\n");
836 		return -ENODEV;
837 	}
838 
839 	ctx->gpio_reset = devm_gpiod_get(ctx->dev, "reset", GPIOD_OUT_LOW);
840 	if (IS_ERR(ctx->gpio_reset)) {
841 		dev_err(ctx->dev, "failed to get reset gpio from DT\n");
842 		return PTR_ERR(ctx->gpio_reset);
843 	}
844 
845 	ctx->supplies[0].supply = "avcc12";
846 	ctx->supplies[1].supply = "avcc33";
847 	ctx->supplies[2].supply = "iovcc18";
848 	ctx->supplies[3].supply = "cvcc12";
849 	ret = devm_regulator_bulk_get(ctx->dev, 4, ctx->supplies);
850 	if (ret) {
851 		dev_err(ctx->dev, "regulator_bulk failed\n");
852 		return ret;
853 	}
854 
855 	ctx->client[I2C_MHL] = client;
856 
857 	ctx->client[I2C_TPI] = i2c_new_dummy(adapter, I2C_TPI_ADDR);
858 	if (!ctx->client[I2C_TPI]) {
859 		dev_err(ctx->dev, "failed to create TPI client\n");
860 		return -ENODEV;
861 	}
862 
863 	ctx->client[I2C_HDMI] = i2c_new_dummy(adapter, I2C_HDMI_ADDR);
864 	if (!ctx->client[I2C_HDMI]) {
865 		dev_err(ctx->dev, "failed to create HDMI RX client\n");
866 		goto fail_tpi;
867 	}
868 
869 	ctx->client[I2C_CBUS] = i2c_new_dummy(adapter, I2C_CBUS_ADDR);
870 	if (!ctx->client[I2C_CBUS]) {
871 		dev_err(ctx->dev, "failed to create CBUS client\n");
872 		goto fail_hdmi;
873 	}
874 
875 	return 0;
876 
877 fail_hdmi:
878 	i2c_unregister_device(ctx->client[I2C_HDMI]);
879 fail_tpi:
880 	i2c_unregister_device(ctx->client[I2C_TPI]);
881 
882 	return -ENODEV;
883 }
884 
885 static void sii9234_deinit_resources(struct sii9234 *ctx)
886 {
887 	i2c_unregister_device(ctx->client[I2C_CBUS]);
888 	i2c_unregister_device(ctx->client[I2C_HDMI]);
889 	i2c_unregister_device(ctx->client[I2C_TPI]);
890 }
891 
892 static inline struct sii9234 *bridge_to_sii9234(struct drm_bridge *bridge)
893 {
894 	return container_of(bridge, struct sii9234, bridge);
895 }
896 
897 static enum drm_mode_status sii9234_mode_valid(struct drm_bridge *bridge,
898 					 const struct drm_display_mode *mode)
899 {
900 	if (mode->clock > MHL1_MAX_CLK)
901 		return MODE_CLOCK_HIGH;
902 
903 	return MODE_OK;
904 }
905 
906 static const struct drm_bridge_funcs sii9234_bridge_funcs = {
907 	.mode_valid = sii9234_mode_valid,
908 };
909 
910 static int sii9234_probe(struct i2c_client *client,
911 			 const struct i2c_device_id *id)
912 {
913 	struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent);
914 	struct sii9234 *ctx;
915 	struct device *dev = &client->dev;
916 	int ret;
917 
918 	ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
919 	if (!ctx)
920 		return -ENOMEM;
921 
922 	ctx->dev = dev;
923 	mutex_init(&ctx->lock);
924 
925 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
926 		dev_err(dev, "I2C adapter lacks SMBUS feature\n");
927 		return -EIO;
928 	}
929 
930 	if (!client->irq) {
931 		dev_err(dev, "no irq provided\n");
932 		return -EINVAL;
933 	}
934 
935 	irq_set_status_flags(client->irq, IRQ_NOAUTOEN);
936 	ret = devm_request_threaded_irq(dev, client->irq, NULL,
937 					sii9234_irq_thread,
938 					IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
939 					"sii9234", ctx);
940 	if (ret < 0) {
941 		dev_err(dev, "failed to install IRQ handler\n");
942 		return ret;
943 	}
944 
945 	ret = sii9234_init_resources(ctx, client);
946 	if (ret < 0)
947 		return ret;
948 
949 	i2c_set_clientdata(client, ctx);
950 
951 	ctx->bridge.funcs = &sii9234_bridge_funcs;
952 	ctx->bridge.of_node = dev->of_node;
953 	drm_bridge_add(&ctx->bridge);
954 
955 	sii9234_cable_in(ctx);
956 
957 	return 0;
958 }
959 
960 static int sii9234_remove(struct i2c_client *client)
961 {
962 	struct sii9234 *ctx = i2c_get_clientdata(client);
963 
964 	sii9234_cable_out(ctx);
965 	drm_bridge_remove(&ctx->bridge);
966 	sii9234_deinit_resources(ctx);
967 
968 	return 0;
969 }
970 
971 static const struct of_device_id sii9234_dt_match[] = {
972 	{ .compatible = "sil,sii9234" },
973 	{ },
974 };
975 MODULE_DEVICE_TABLE(of, sii9234_dt_match);
976 
977 static const struct i2c_device_id sii9234_id[] = {
978 	{ "SII9234", 0 },
979 	{ },
980 };
981 MODULE_DEVICE_TABLE(i2c, sii9234_id);
982 
983 static struct i2c_driver sii9234_driver = {
984 	.driver = {
985 		.name	= "sii9234",
986 		.of_match_table = sii9234_dt_match,
987 	},
988 	.probe = sii9234_probe,
989 	.remove = sii9234_remove,
990 	.id_table = sii9234_id,
991 };
992 
993 module_i2c_driver(sii9234_driver);
994 MODULE_LICENSE("GPL");
995