xref: /linux/drivers/gpu/drm/bridge/sii9234.c (revision 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d)
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_atomic_state_helper.h>
17 #include <drm/drm_bridge.h>
18 #include <drm/drm_crtc.h>
19 #include <drm/drm_edid.h>
20 
21 #include <linux/delay.h>
22 #include <linux/err.h>
23 #include <linux/gpio/consumer.h>
24 #include <linux/i2c.h>
25 #include <linux/interrupt.h>
26 #include <linux/irq.h>
27 #include <linux/kernel.h>
28 #include <linux/module.h>
29 #include <linux/mutex.h>
30 #include <linux/regulator/consumer.h>
31 #include <linux/slab.h>
32 
33 #define CBUS_DEVCAP_OFFSET		0x80
34 
35 #define SII9234_MHL_VERSION		0x11
36 #define SII9234_SCRATCHPAD_SIZE		0x10
37 #define SII9234_INT_STAT_SIZE		0x33
38 
39 #define BIT_TMDS_CCTRL_TMDS_OE		BIT(4)
40 #define MHL_HPD_OUT_OVR_EN		BIT(4)
41 #define MHL_HPD_OUT_OVR_VAL		BIT(5)
42 #define MHL_INIT_TIMEOUT		0x0C
43 
44 /* MHL Tx registers and bits */
45 #define MHL_TX_SRST			0x05
46 #define MHL_TX_SYSSTAT_REG		0x09
47 #define MHL_TX_INTR1_REG		0x71
48 #define MHL_TX_INTR4_REG		0x74
49 #define MHL_TX_INTR1_ENABLE_REG		0x75
50 #define MHL_TX_INTR4_ENABLE_REG		0x78
51 #define MHL_TX_INT_CTRL_REG		0x79
52 #define MHL_TX_TMDS_CCTRL		0x80
53 #define MHL_TX_DISC_CTRL1_REG		0x90
54 #define MHL_TX_DISC_CTRL2_REG		0x91
55 #define MHL_TX_DISC_CTRL3_REG		0x92
56 #define MHL_TX_DISC_CTRL4_REG		0x93
57 #define MHL_TX_DISC_CTRL5_REG		0x94
58 #define MHL_TX_DISC_CTRL6_REG		0x95
59 #define MHL_TX_DISC_CTRL7_REG		0x96
60 #define MHL_TX_DISC_CTRL8_REG		0x97
61 #define MHL_TX_STAT2_REG		0x99
62 #define MHL_TX_MHLTX_CTL1_REG		0xA0
63 #define MHL_TX_MHLTX_CTL2_REG		0xA1
64 #define MHL_TX_MHLTX_CTL4_REG		0xA3
65 #define MHL_TX_MHLTX_CTL6_REG		0xA5
66 #define MHL_TX_MHLTX_CTL7_REG		0xA6
67 
68 #define RSEN_STATUS			BIT(2)
69 #define HPD_CHANGE_INT			BIT(6)
70 #define RSEN_CHANGE_INT			BIT(5)
71 #define RGND_READY_INT			BIT(6)
72 #define VBUS_LOW_INT			BIT(5)
73 #define CBUS_LKOUT_INT			BIT(4)
74 #define MHL_DISC_FAIL_INT		BIT(3)
75 #define MHL_EST_INT			BIT(2)
76 #define HPD_CHANGE_INT_MASK		BIT(6)
77 #define RSEN_CHANGE_INT_MASK		BIT(5)
78 
79 #define RGND_READY_MASK			BIT(6)
80 #define CBUS_LKOUT_MASK			BIT(4)
81 #define MHL_DISC_FAIL_MASK		BIT(3)
82 #define MHL_EST_MASK			BIT(2)
83 
84 #define SKIP_GND			BIT(6)
85 
86 #define ATT_THRESH_SHIFT		0x04
87 #define ATT_THRESH_MASK			(0x03 << ATT_THRESH_SHIFT)
88 #define USB_D_OEN			BIT(3)
89 #define DEGLITCH_TIME_MASK		0x07
90 #define DEGLITCH_TIME_2MS		0
91 #define DEGLITCH_TIME_4MS		1
92 #define DEGLITCH_TIME_8MS		2
93 #define DEGLITCH_TIME_16MS		3
94 #define DEGLITCH_TIME_40MS		4
95 #define DEGLITCH_TIME_50MS		5
96 #define DEGLITCH_TIME_60MS		6
97 #define DEGLITCH_TIME_128MS		7
98 
99 #define USB_D_OVR			BIT(7)
100 #define USB_ID_OVR			BIT(6)
101 #define DVRFLT_SEL			BIT(5)
102 #define BLOCK_RGND_INT			BIT(4)
103 #define SKIP_DEG			BIT(3)
104 #define CI2CA_POL			BIT(2)
105 #define CI2CA_WKUP			BIT(1)
106 #define SINGLE_ATT			BIT(0)
107 
108 #define USB_D_ODN			BIT(5)
109 #define VBUS_CHECK			BIT(2)
110 #define RGND_INTP_MASK			0x03
111 #define RGND_INTP_OPEN			0
112 #define RGND_INTP_2K			1
113 #define RGND_INTP_1K			2
114 #define RGND_INTP_SHORT			3
115 
116 /* HDMI registers */
117 #define HDMI_RX_TMDS0_CCTRL1_REG	0x10
118 #define HDMI_RX_TMDS_CLK_EN_REG		0x11
119 #define HDMI_RX_TMDS_CH_EN_REG		0x12
120 #define HDMI_RX_PLL_CALREFSEL_REG	0x17
121 #define HDMI_RX_PLL_VCOCAL_REG		0x1A
122 #define HDMI_RX_EQ_DATA0_REG		0x22
123 #define HDMI_RX_EQ_DATA1_REG		0x23
124 #define HDMI_RX_EQ_DATA2_REG		0x24
125 #define HDMI_RX_EQ_DATA3_REG		0x25
126 #define HDMI_RX_EQ_DATA4_REG		0x26
127 #define HDMI_RX_TMDS_ZONE_CTRL_REG	0x4C
128 #define HDMI_RX_TMDS_MODE_CTRL_REG	0x4D
129 
130 /* CBUS registers */
131 #define CBUS_INT_STATUS_1_REG		0x08
132 #define CBUS_INTR1_ENABLE_REG		0x09
133 #define CBUS_MSC_REQ_ABORT_REASON_REG	0x0D
134 #define CBUS_INT_STATUS_2_REG		0x1E
135 #define CBUS_INTR2_ENABLE_REG		0x1F
136 #define CBUS_LINK_CONTROL_2_REG		0x31
137 #define CBUS_MHL_STATUS_REG_0		0xB0
138 #define CBUS_MHL_STATUS_REG_1		0xB1
139 
140 #define BIT_CBUS_RESET			BIT(3)
141 #define SET_HPD_DOWNSTREAM		BIT(6)
142 
143 /* TPI registers */
144 #define TPI_DPD_REG			0x3D
145 
146 /* Timeouts in msec */
147 #define T_SRC_VBUS_CBUS_TO_STABLE	200
148 #define T_SRC_CBUS_FLOAT		100
149 #define T_SRC_CBUS_DEGLITCH		2
150 #define T_SRC_RXSENSE_DEGLITCH		110
151 
152 #define MHL1_MAX_CLK			75000 /* in kHz */
153 
154 #define I2C_TPI_ADDR			0x3D
155 #define I2C_HDMI_ADDR			0x49
156 #define I2C_CBUS_ADDR			0x64
157 
158 enum sii9234_state {
159 	ST_OFF,
160 	ST_D3,
161 	ST_RGND_INIT,
162 	ST_RGND_1K,
163 	ST_RSEN_HIGH,
164 	ST_MHL_ESTABLISHED,
165 	ST_FAILURE_DISCOVERY,
166 	ST_FAILURE,
167 };
168 
169 struct sii9234 {
170 	struct i2c_client *client[4];
171 	struct drm_bridge bridge;
172 	struct device *dev;
173 	struct gpio_desc *gpio_reset;
174 	int i2c_error;
175 	struct regulator_bulk_data supplies[4];
176 
177 	struct mutex lock; /* Protects fields below and device registers */
178 	enum sii9234_state state;
179 };
180 
181 enum sii9234_client_id {
182 	I2C_MHL,
183 	I2C_TPI,
184 	I2C_HDMI,
185 	I2C_CBUS,
186 };
187 
188 static const char * const sii9234_client_name[] = {
189 	[I2C_MHL] = "MHL",
190 	[I2C_TPI] = "TPI",
191 	[I2C_HDMI] = "HDMI",
192 	[I2C_CBUS] = "CBUS",
193 };
194 
195 static int sii9234_writeb(struct sii9234 *ctx, int id, int offset,
196 			  int value)
197 {
198 	int ret;
199 	struct i2c_client *client = ctx->client[id];
200 
201 	if (ctx->i2c_error)
202 		return ctx->i2c_error;
203 
204 	ret = i2c_smbus_write_byte_data(client, offset, value);
205 	if (ret < 0)
206 		dev_err(ctx->dev, "writeb: %4s[0x%02x] <- 0x%02x\n",
207 			sii9234_client_name[id], offset, value);
208 	ctx->i2c_error = ret;
209 
210 	return ret;
211 }
212 
213 static int sii9234_writebm(struct sii9234 *ctx, int id, int offset,
214 			   int value, int mask)
215 {
216 	int ret;
217 	struct i2c_client *client = ctx->client[id];
218 
219 	if (ctx->i2c_error)
220 		return ctx->i2c_error;
221 
222 	ret = i2c_smbus_write_byte(client, offset);
223 	if (ret < 0) {
224 		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
225 			sii9234_client_name[id], offset, value);
226 		ctx->i2c_error = ret;
227 		return ret;
228 	}
229 
230 	ret = i2c_smbus_read_byte(client);
231 	if (ret < 0) {
232 		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
233 			sii9234_client_name[id], offset, value);
234 		ctx->i2c_error = ret;
235 		return ret;
236 	}
237 
238 	value = (value & mask) | (ret & ~mask);
239 
240 	ret = i2c_smbus_write_byte_data(client, offset, value);
241 	if (ret < 0) {
242 		dev_err(ctx->dev, "writebm: %4s[0x%02x] <- 0x%02x\n",
243 			sii9234_client_name[id], offset, value);
244 		ctx->i2c_error = ret;
245 	}
246 
247 	return ret;
248 }
249 
250 static int sii9234_readb(struct sii9234 *ctx, int id, int offset)
251 {
252 	int ret;
253 	struct i2c_client *client = ctx->client[id];
254 
255 	if (ctx->i2c_error)
256 		return ctx->i2c_error;
257 
258 	ret = i2c_smbus_write_byte(client, offset);
259 	if (ret < 0) {
260 		dev_err(ctx->dev, "readb: %4s[0x%02x]\n",
261 			sii9234_client_name[id], offset);
262 		ctx->i2c_error = ret;
263 		return ret;
264 	}
265 
266 	ret = i2c_smbus_read_byte(client);
267 	if (ret < 0) {
268 		dev_err(ctx->dev, "readb: %4s[0x%02x]\n",
269 			sii9234_client_name[id], offset);
270 		ctx->i2c_error = ret;
271 	}
272 
273 	return ret;
274 }
275 
276 static int sii9234_clear_error(struct sii9234 *ctx)
277 {
278 	int ret = ctx->i2c_error;
279 
280 	ctx->i2c_error = 0;
281 
282 	return ret;
283 }
284 
285 #define mhl_tx_writeb(sii9234, offset, value) \
286 	sii9234_writeb(sii9234, I2C_MHL, offset, value)
287 #define mhl_tx_writebm(sii9234, offset, value, mask) \
288 	sii9234_writebm(sii9234, I2C_MHL, offset, value, mask)
289 #define mhl_tx_readb(sii9234, offset) \
290 	sii9234_readb(sii9234, I2C_MHL, offset)
291 #define cbus_writeb(sii9234, offset, value) \
292 	sii9234_writeb(sii9234, I2C_CBUS, offset, value)
293 #define cbus_writebm(sii9234, offset, value, mask) \
294 	sii9234_writebm(sii9234, I2C_CBUS, offset, value, mask)
295 #define cbus_readb(sii9234, offset) \
296 	sii9234_readb(sii9234, I2C_CBUS, offset)
297 #define hdmi_writeb(sii9234, offset, value) \
298 	sii9234_writeb(sii9234, I2C_HDMI, offset, value)
299 #define hdmi_writebm(sii9234, offset, value, mask) \
300 	sii9234_writebm(sii9234, I2C_HDMI, offset, value, mask)
301 #define hdmi_readb(sii9234, offset) \
302 	sii9234_readb(sii9234, I2C_HDMI, offset)
303 #define tpi_writeb(sii9234, offset, value) \
304 	sii9234_writeb(sii9234, I2C_TPI, offset, value)
305 #define tpi_writebm(sii9234, offset, value, mask) \
306 	sii9234_writebm(sii9234, I2C_TPI, offset, value, mask)
307 #define tpi_readb(sii9234, offset) \
308 	sii9234_readb(sii9234, I2C_TPI, offset)
309 
310 static u8 sii9234_tmds_control(struct sii9234 *ctx, bool enable)
311 {
312 	mhl_tx_writebm(ctx, MHL_TX_TMDS_CCTRL, enable ? ~0 : 0,
313 		       BIT_TMDS_CCTRL_TMDS_OE);
314 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, enable ? ~0 : 0,
315 		       MHL_HPD_OUT_OVR_EN | MHL_HPD_OUT_OVR_VAL);
316 	return sii9234_clear_error(ctx);
317 }
318 
319 static int sii9234_cbus_reset(struct sii9234 *ctx)
320 {
321 	int i;
322 
323 	mhl_tx_writebm(ctx, MHL_TX_SRST, ~0, BIT_CBUS_RESET);
324 	msleep(T_SRC_CBUS_DEGLITCH);
325 	mhl_tx_writebm(ctx, MHL_TX_SRST, 0, BIT_CBUS_RESET);
326 
327 	for (i = 0; i < 4; i++) {
328 		/*
329 		 * Enable WRITE_STAT interrupt for writes to all
330 		 * 4 MSC Status registers.
331 		 */
332 		cbus_writeb(ctx, 0xE0 + i, 0xF2);
333 		/*
334 		 * Enable SET_INT interrupt for writes to all
335 		 * 4 MSC Interrupt registers.
336 		 */
337 		cbus_writeb(ctx, 0xF0 + i, 0xF2);
338 	}
339 
340 	return sii9234_clear_error(ctx);
341 }
342 
343 /* Require to check mhl information of samsung in cbus_init_register */
344 static int sii9234_cbus_init(struct sii9234 *ctx)
345 {
346 	cbus_writeb(ctx, 0x07, 0xF2);
347 	cbus_writeb(ctx, 0x40, 0x03);
348 	cbus_writeb(ctx, 0x42, 0x06);
349 	cbus_writeb(ctx, 0x36, 0x0C);
350 	cbus_writeb(ctx, 0x3D, 0xFD);
351 	cbus_writeb(ctx, 0x1C, 0x01);
352 	cbus_writeb(ctx, 0x1D, 0x0F);
353 	cbus_writeb(ctx, 0x44, 0x02);
354 	/* Setup our devcap */
355 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_DEV_STATE, 0x00);
356 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_MHL_VERSION,
357 		    SII9234_MHL_VERSION);
358 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_CAT,
359 		    MHL_DCAP_CAT_SOURCE);
360 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_ADOPTER_ID_H, 0x01);
361 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_ADOPTER_ID_L, 0x41);
362 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_VID_LINK_MODE,
363 		    MHL_DCAP_VID_LINK_RGB444 | MHL_DCAP_VID_LINK_YCBCR444);
364 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_VIDEO_TYPE,
365 		    MHL_DCAP_VT_GRAPHICS);
366 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_LOG_DEV_MAP,
367 		    MHL_DCAP_LD_GUI);
368 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_BANDWIDTH, 0x0F);
369 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_FEATURE_FLAG,
370 		    MHL_DCAP_FEATURE_RCP_SUPPORT | MHL_DCAP_FEATURE_RAP_SUPPORT
371 			| MHL_DCAP_FEATURE_SP_SUPPORT);
372 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_DEVICE_ID_H, 0x0);
373 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_DEVICE_ID_L, 0x0);
374 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_SCRATCHPAD_SIZE,
375 		    SII9234_SCRATCHPAD_SIZE);
376 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_INT_STAT_SIZE,
377 		    SII9234_INT_STAT_SIZE);
378 	cbus_writeb(ctx, CBUS_DEVCAP_OFFSET + MHL_DCAP_RESERVED, 0);
379 	cbus_writebm(ctx, 0x31, 0x0C, 0x0C);
380 	cbus_writeb(ctx, 0x30, 0x01);
381 	cbus_writebm(ctx, 0x3C, 0x30, 0x38);
382 	cbus_writebm(ctx, 0x22, 0x0D, 0x0F);
383 	cbus_writebm(ctx, 0x2E, 0x15, 0x15);
384 	cbus_writeb(ctx, CBUS_INTR1_ENABLE_REG, 0);
385 	cbus_writeb(ctx, CBUS_INTR2_ENABLE_REG, 0);
386 
387 	return sii9234_clear_error(ctx);
388 }
389 
390 static void force_usb_id_switch_open(struct sii9234 *ctx)
391 {
392 	/* Disable CBUS discovery */
393 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, 0, 0x01);
394 	/* Force USB ID switch to open */
395 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, USB_ID_OVR);
396 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL3_REG, ~0, 0x86);
397 	/* Force upstream HPD to 0 when not in MHL mode. */
398 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 0x30);
399 }
400 
401 static void release_usb_id_switch_open(struct sii9234 *ctx)
402 {
403 	msleep(T_SRC_CBUS_FLOAT);
404 	/* Clear USB ID switch to open */
405 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, 0, USB_ID_OVR);
406 	/* Enable CBUS discovery */
407 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, ~0, 0x01);
408 }
409 
410 static int sii9234_power_init(struct sii9234 *ctx)
411 {
412 	/* Force the SiI9234 into the D0 state. */
413 	tpi_writeb(ctx, TPI_DPD_REG, 0x3F);
414 	/* Enable TxPLL Clock */
415 	hdmi_writeb(ctx, HDMI_RX_TMDS_CLK_EN_REG, 0x01);
416 	/* Enable Tx Clock Path & Equalizer */
417 	hdmi_writeb(ctx, HDMI_RX_TMDS_CH_EN_REG, 0x15);
418 	/* Power Up TMDS */
419 	mhl_tx_writeb(ctx, 0x08, 0x35);
420 	return sii9234_clear_error(ctx);
421 }
422 
423 static int sii9234_hdmi_init(struct sii9234 *ctx)
424 {
425 	hdmi_writeb(ctx, HDMI_RX_TMDS0_CCTRL1_REG, 0xC1);
426 	hdmi_writeb(ctx, HDMI_RX_PLL_CALREFSEL_REG, 0x03);
427 	hdmi_writeb(ctx, HDMI_RX_PLL_VCOCAL_REG, 0x20);
428 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA0_REG, 0x8A);
429 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA1_REG, 0x6A);
430 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA2_REG, 0xAA);
431 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA3_REG, 0xCA);
432 	hdmi_writeb(ctx, HDMI_RX_EQ_DATA4_REG, 0xEA);
433 	hdmi_writeb(ctx, HDMI_RX_TMDS_ZONE_CTRL_REG, 0xA0);
434 	hdmi_writeb(ctx, HDMI_RX_TMDS_MODE_CTRL_REG, 0x00);
435 	mhl_tx_writeb(ctx, MHL_TX_TMDS_CCTRL, 0x34);
436 	hdmi_writeb(ctx, 0x45, 0x44);
437 	hdmi_writeb(ctx, 0x31, 0x0A);
438 	hdmi_writeb(ctx, HDMI_RX_TMDS0_CCTRL1_REG, 0xC1);
439 
440 	return sii9234_clear_error(ctx);
441 }
442 
443 static int sii9234_mhl_tx_ctl_int(struct sii9234 *ctx)
444 {
445 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL1_REG, 0xD0);
446 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL2_REG, 0xFC);
447 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL4_REG, 0xEB);
448 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL7_REG, 0x0C);
449 
450 	return sii9234_clear_error(ctx);
451 }
452 
453 static int sii9234_reset(struct sii9234 *ctx)
454 {
455 	int ret;
456 
457 	sii9234_clear_error(ctx);
458 
459 	ret = sii9234_power_init(ctx);
460 	if (ret < 0)
461 		return ret;
462 	ret = sii9234_cbus_reset(ctx);
463 	if (ret < 0)
464 		return ret;
465 	ret = sii9234_hdmi_init(ctx);
466 	if (ret < 0)
467 		return ret;
468 	ret = sii9234_mhl_tx_ctl_int(ctx);
469 	if (ret < 0)
470 		return ret;
471 
472 	/* Enable HDCP Compliance safety */
473 	mhl_tx_writeb(ctx, 0x2B, 0x01);
474 	/* CBUS discovery cycle time for each drive and float = 150us */
475 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, 0x04, 0x06);
476 	/* Clear bit 6 (reg_skip_rgnd) */
477 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL2_REG, (1 << 7) /* Reserved */
478 		      | 2 << ATT_THRESH_SHIFT | DEGLITCH_TIME_50MS);
479 	/*
480 	 * Changed from 66 to 65 for 94[1:0] = 01 = 5k reg_cbusmhl_pup_sel
481 	 * 1.8V CBUS VTH & GND threshold
482 	 * to meet CTS 3.3.7.2 spec
483 	 */
484 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL5_REG, 0x77);
485 	cbus_writebm(ctx, CBUS_LINK_CONTROL_2_REG, ~0, MHL_INIT_TIMEOUT);
486 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL6_REG, 0xA0);
487 	/* RGND & single discovery attempt (RGND blocking) */
488 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL6_REG, BLOCK_RGND_INT |
489 		      DVRFLT_SEL | SINGLE_ATT);
490 	/* Use VBUS path of discovery state machine */
491 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL8_REG, 0);
492 	/* 0x92[3] sets the CBUS / ID switch */
493 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, USB_ID_OVR);
494 	/*
495 	 * To allow RGND engine to operate correctly.
496 	 * When moving the chip from D2 to D0 (power up, init regs)
497 	 * the values should be
498 	 * 94[1:0] = 01  reg_cbusmhl_pup_sel[1:0] should be set for 5k
499 	 * 93[7:6] = 10  reg_cbusdisc_pup_sel[1:0] should be
500 	 * set for 10k (default)
501 	 * 93[5:4] = 00  reg_cbusidle_pup_sel[1:0] = open (default)
502 	 */
503 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL3_REG, ~0, 0x86);
504 	/*
505 	 * Change from CC to 8C to match 5K
506 	 * to meet CTS 3.3.72 spec
507 	 */
508 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, ~0, 0x8C);
509 	/* Configure the interrupt as active high */
510 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 0x06);
511 
512 	msleep(25);
513 
514 	/* Release usb_id switch */
515 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, 0,  USB_ID_OVR);
516 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL1_REG, 0x27);
517 
518 	ret = sii9234_clear_error(ctx);
519 	if (ret < 0)
520 		return ret;
521 	ret = sii9234_cbus_init(ctx);
522 	if (ret < 0)
523 		return ret;
524 
525 	/* Enable Auto soft reset on SCDT = 0 */
526 	mhl_tx_writeb(ctx, 0x05, 0x04);
527 	/* HDMI Transcode mode enable */
528 	mhl_tx_writeb(ctx, 0x0D, 0x1C);
529 	mhl_tx_writeb(ctx, MHL_TX_INTR4_ENABLE_REG,
530 		      RGND_READY_MASK | CBUS_LKOUT_MASK
531 			| MHL_DISC_FAIL_MASK | MHL_EST_MASK);
532 	mhl_tx_writeb(ctx, MHL_TX_INTR1_ENABLE_REG, 0x60);
533 
534 	/* This point is very important before measure RGND impedance */
535 	force_usb_id_switch_open(ctx);
536 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, 0, 0xF0);
537 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL5_REG, 0, 0x03);
538 	release_usb_id_switch_open(ctx);
539 
540 	/* Force upstream HPD to 0 when not in MHL mode */
541 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, 0, 1 << 5);
542 	mhl_tx_writebm(ctx, MHL_TX_INT_CTRL_REG, ~0, 1 << 4);
543 
544 	return sii9234_clear_error(ctx);
545 }
546 
547 static int sii9234_goto_d3(struct sii9234 *ctx)
548 {
549 	int ret;
550 
551 	dev_dbg(ctx->dev, "sii9234: detection started d3\n");
552 
553 	ret = sii9234_reset(ctx);
554 	if (ret < 0)
555 		goto exit;
556 
557 	hdmi_writeb(ctx, 0x01, 0x03);
558 	tpi_writebm(ctx, TPI_DPD_REG, 0, 1);
559 	/* I2C above is expected to fail because power goes down */
560 	sii9234_clear_error(ctx);
561 
562 	ctx->state = ST_D3;
563 
564 	return 0;
565  exit:
566 	dev_err(ctx->dev, "%s failed\n", __func__);
567 	return -1;
568 }
569 
570 static int sii9234_hw_on(struct sii9234 *ctx)
571 {
572 	return regulator_bulk_enable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
573 }
574 
575 static void sii9234_hw_off(struct sii9234 *ctx)
576 {
577 	gpiod_set_value(ctx->gpio_reset, 1);
578 	msleep(20);
579 	regulator_bulk_disable(ARRAY_SIZE(ctx->supplies), ctx->supplies);
580 }
581 
582 static void sii9234_hw_reset(struct sii9234 *ctx)
583 {
584 	gpiod_set_value(ctx->gpio_reset, 1);
585 	msleep(20);
586 	gpiod_set_value(ctx->gpio_reset, 0);
587 }
588 
589 static void sii9234_cable_in(struct sii9234 *ctx)
590 {
591 	int ret;
592 
593 	mutex_lock(&ctx->lock);
594 	if (ctx->state != ST_OFF)
595 		goto unlock;
596 	ret = sii9234_hw_on(ctx);
597 	if (ret < 0)
598 		goto unlock;
599 
600 	sii9234_hw_reset(ctx);
601 	sii9234_goto_d3(ctx);
602 	/* To avoid irq storm, when hw is in meta state */
603 	enable_irq(to_i2c_client(ctx->dev)->irq);
604 
605 unlock:
606 	mutex_unlock(&ctx->lock);
607 }
608 
609 static void sii9234_cable_out(struct sii9234 *ctx)
610 {
611 	mutex_lock(&ctx->lock);
612 
613 	if (ctx->state == ST_OFF)
614 		goto unlock;
615 
616 	disable_irq(to_i2c_client(ctx->dev)->irq);
617 	tpi_writeb(ctx, TPI_DPD_REG, 0);
618 	/* Turn on&off hpd feature for only QCT HDMI */
619 	sii9234_hw_off(ctx);
620 
621 	ctx->state = ST_OFF;
622 
623 unlock:
624 	mutex_unlock(&ctx->lock);
625 }
626 
627 static enum sii9234_state sii9234_rgnd_ready_irq(struct sii9234 *ctx)
628 {
629 	int value;
630 
631 	if (ctx->state == ST_D3) {
632 		int ret;
633 
634 		dev_dbg(ctx->dev, "RGND_READY_INT\n");
635 		sii9234_hw_reset(ctx);
636 
637 		ret = sii9234_reset(ctx);
638 		if (ret < 0) {
639 			dev_err(ctx->dev, "sii9234_reset() failed\n");
640 			return ST_FAILURE;
641 		}
642 
643 		return ST_RGND_INIT;
644 	}
645 
646 	/* Got interrupt in inappropriate state */
647 	if (ctx->state != ST_RGND_INIT)
648 		return ST_FAILURE;
649 
650 	value = mhl_tx_readb(ctx, MHL_TX_STAT2_REG);
651 	if (sii9234_clear_error(ctx))
652 		return ST_FAILURE;
653 
654 	if ((value & RGND_INTP_MASK) != RGND_INTP_1K) {
655 		dev_warn(ctx->dev, "RGND is not 1k\n");
656 		return ST_RGND_INIT;
657 	}
658 	dev_dbg(ctx->dev, "RGND 1K!!\n");
659 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL4_REG, ~0, 0x8C);
660 	mhl_tx_writeb(ctx, MHL_TX_DISC_CTRL5_REG, 0x77);
661 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL6_REG, ~0, 0x05);
662 	if (sii9234_clear_error(ctx))
663 		return ST_FAILURE;
664 
665 	msleep(T_SRC_VBUS_CBUS_TO_STABLE);
666 	return ST_RGND_1K;
667 }
668 
669 static enum sii9234_state sii9234_mhl_established(struct sii9234 *ctx)
670 {
671 	dev_dbg(ctx->dev, "mhl est interrupt\n");
672 
673 	/* Discovery override */
674 	mhl_tx_writeb(ctx, MHL_TX_MHLTX_CTL1_REG, 0x10);
675 	/* Increase DDC translation layer timer (byte mode) */
676 	cbus_writeb(ctx, 0x07, 0x32);
677 	cbus_writebm(ctx, 0x44, ~0, 1 << 1);
678 	/* Keep the discovery enabled. Need RGND interrupt */
679 	mhl_tx_writebm(ctx, MHL_TX_DISC_CTRL1_REG, ~0, 1);
680 	mhl_tx_writeb(ctx, MHL_TX_INTR1_ENABLE_REG,
681 		      RSEN_CHANGE_INT_MASK | HPD_CHANGE_INT_MASK);
682 
683 	if (sii9234_clear_error(ctx))
684 		return ST_FAILURE;
685 
686 	return ST_MHL_ESTABLISHED;
687 }
688 
689 static enum sii9234_state sii9234_hpd_change(struct sii9234 *ctx)
690 {
691 	int value;
692 
693 	value = cbus_readb(ctx, CBUS_MSC_REQ_ABORT_REASON_REG);
694 	if (sii9234_clear_error(ctx))
695 		return ST_FAILURE;
696 
697 	if (value & SET_HPD_DOWNSTREAM) {
698 		/* Downstream HPD High, Enable TMDS */
699 		sii9234_tmds_control(ctx, true);
700 	} else {
701 		/* Downstream HPD Low, Disable TMDS */
702 		sii9234_tmds_control(ctx, false);
703 	}
704 
705 	return ctx->state;
706 }
707 
708 static enum sii9234_state sii9234_rsen_change(struct sii9234 *ctx)
709 {
710 	int value;
711 
712 	/* Workaround code to handle wrong interrupt */
713 	if (ctx->state != ST_RGND_1K) {
714 		dev_err(ctx->dev, "RSEN_HIGH without RGND_1K\n");
715 		return ST_FAILURE;
716 	}
717 	value = mhl_tx_readb(ctx, MHL_TX_SYSSTAT_REG);
718 	if (value < 0)
719 		return ST_FAILURE;
720 
721 	if (value & RSEN_STATUS) {
722 		dev_dbg(ctx->dev, "MHL cable connected.. RSEN High\n");
723 		return ST_RSEN_HIGH;
724 	}
725 	dev_dbg(ctx->dev, "RSEN lost\n");
726 	/*
727 	 * Once RSEN loss is confirmed, we need to check
728 	 * based on cable status and chip power status, whether
729 	 * it is SINK Loss (HDMI cable not connected, TV Off)
730 	 * or MHL cable disconnection
731 	 * TODO: Define the below mhl_disconnection()
732 	 */
733 	msleep(T_SRC_RXSENSE_DEGLITCH);
734 	value = mhl_tx_readb(ctx, MHL_TX_SYSSTAT_REG);
735 	if (value < 0)
736 		return ST_FAILURE;
737 	dev_dbg(ctx->dev, "sys_stat: %x\n", value);
738 
739 	if (value & RSEN_STATUS) {
740 		dev_dbg(ctx->dev, "RSEN recovery\n");
741 		return ST_RSEN_HIGH;
742 	}
743 	dev_dbg(ctx->dev, "RSEN Really LOW\n");
744 	/* To meet CTS 3.3.22.2 spec */
745 	sii9234_tmds_control(ctx, false);
746 	force_usb_id_switch_open(ctx);
747 	release_usb_id_switch_open(ctx);
748 
749 	return ST_FAILURE;
750 }
751 
752 static irqreturn_t sii9234_irq_thread(int irq, void *data)
753 {
754 	struct sii9234 *ctx = data;
755 	int intr1, intr4;
756 	int intr1_en, intr4_en;
757 	int cbus_intr1, cbus_intr2;
758 
759 	dev_dbg(ctx->dev, "%s\n", __func__);
760 
761 	mutex_lock(&ctx->lock);
762 
763 	intr1 = mhl_tx_readb(ctx, MHL_TX_INTR1_REG);
764 	intr4 = mhl_tx_readb(ctx, MHL_TX_INTR4_REG);
765 	intr1_en = mhl_tx_readb(ctx, MHL_TX_INTR1_ENABLE_REG);
766 	intr4_en = mhl_tx_readb(ctx, MHL_TX_INTR4_ENABLE_REG);
767 	cbus_intr1 = cbus_readb(ctx, CBUS_INT_STATUS_1_REG);
768 	cbus_intr2 = cbus_readb(ctx, CBUS_INT_STATUS_2_REG);
769 
770 	if (sii9234_clear_error(ctx))
771 		goto done;
772 
773 	dev_dbg(ctx->dev, "irq %02x/%02x %02x/%02x %02x/%02x\n",
774 		intr1, intr1_en, intr4, intr4_en, cbus_intr1, cbus_intr2);
775 
776 	if (intr4 & RGND_READY_INT)
777 		ctx->state = sii9234_rgnd_ready_irq(ctx);
778 	if (intr1 & RSEN_CHANGE_INT)
779 		ctx->state = sii9234_rsen_change(ctx);
780 	if (intr4 & MHL_EST_INT)
781 		ctx->state = sii9234_mhl_established(ctx);
782 	if (intr1 & HPD_CHANGE_INT)
783 		ctx->state = sii9234_hpd_change(ctx);
784 	if (intr4 & CBUS_LKOUT_INT)
785 		ctx->state = ST_FAILURE;
786 	if (intr4 & MHL_DISC_FAIL_INT)
787 		ctx->state = ST_FAILURE_DISCOVERY;
788 
789  done:
790 	/* Clean interrupt status and pending flags */
791 	mhl_tx_writeb(ctx, MHL_TX_INTR1_REG, intr1);
792 	mhl_tx_writeb(ctx, MHL_TX_INTR4_REG, intr4);
793 	cbus_writeb(ctx, CBUS_MHL_STATUS_REG_0, 0xFF);
794 	cbus_writeb(ctx, CBUS_MHL_STATUS_REG_1, 0xFF);
795 	cbus_writeb(ctx, CBUS_INT_STATUS_1_REG, cbus_intr1);
796 	cbus_writeb(ctx, CBUS_INT_STATUS_2_REG, cbus_intr2);
797 
798 	sii9234_clear_error(ctx);
799 
800 	if (ctx->state == ST_FAILURE) {
801 		dev_dbg(ctx->dev, "try to reset after failure\n");
802 		sii9234_hw_reset(ctx);
803 		sii9234_goto_d3(ctx);
804 	}
805 
806 	if (ctx->state == ST_FAILURE_DISCOVERY) {
807 		dev_err(ctx->dev, "discovery failed, no power for MHL?\n");
808 		tpi_writebm(ctx, TPI_DPD_REG, 0, 1);
809 		ctx->state = ST_D3;
810 	}
811 
812 	mutex_unlock(&ctx->lock);
813 
814 	return IRQ_HANDLED;
815 }
816 
817 static int sii9234_init_resources(struct sii9234 *ctx,
818 				  struct i2c_client *client)
819 {
820 	struct i2c_adapter *adapter = client->adapter;
821 	int ret;
822 
823 	if (!ctx->dev->of_node) {
824 		dev_err(ctx->dev, "no DT device\n");
825 		return -ENODEV;
826 	}
827 
828 	ctx->gpio_reset = devm_gpiod_get(ctx->dev, "reset", GPIOD_OUT_LOW);
829 	if (IS_ERR(ctx->gpio_reset))
830 		return dev_err_probe(ctx->dev, PTR_ERR(ctx->gpio_reset),
831 				     "failed to get reset gpio from DT\n");
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 		return dev_err_probe(ctx->dev, ret, "regulator_bulk failed\n");
840 
841 	ctx->client[I2C_MHL] = client;
842 
843 	ctx->client[I2C_TPI] = devm_i2c_new_dummy_device(&client->dev, adapter,
844 							 I2C_TPI_ADDR);
845 	if (IS_ERR(ctx->client[I2C_TPI])) {
846 		dev_err(ctx->dev, "failed to create TPI client\n");
847 		return PTR_ERR(ctx->client[I2C_TPI]);
848 	}
849 
850 	ctx->client[I2C_HDMI] = devm_i2c_new_dummy_device(&client->dev, adapter,
851 							  I2C_HDMI_ADDR);
852 	if (IS_ERR(ctx->client[I2C_HDMI])) {
853 		dev_err(ctx->dev, "failed to create HDMI RX client\n");
854 		return PTR_ERR(ctx->client[I2C_HDMI]);
855 	}
856 
857 	ctx->client[I2C_CBUS] = devm_i2c_new_dummy_device(&client->dev, adapter,
858 							  I2C_CBUS_ADDR);
859 	if (IS_ERR(ctx->client[I2C_CBUS])) {
860 		dev_err(ctx->dev, "failed to create CBUS client\n");
861 		return PTR_ERR(ctx->client[I2C_CBUS]);
862 	}
863 
864 	return 0;
865 }
866 
867 static enum drm_mode_status sii9234_mode_valid(struct drm_bridge *bridge,
868 					 const struct drm_display_info *info,
869 					 const struct drm_display_mode *mode)
870 {
871 	if (mode->clock > MHL1_MAX_CLK)
872 		return MODE_CLOCK_HIGH;
873 
874 	return MODE_OK;
875 }
876 
877 static const struct drm_bridge_funcs sii9234_bridge_funcs = {
878 	.atomic_create_state = drm_atomic_helper_bridge_create_state,
879 	.atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
880 	.atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
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_drm_bridge_alloc(dev, struct sii9234, bridge,
892 				    &sii9234_bridge_funcs);
893 	if (IS_ERR(ctx))
894 		return PTR_ERR(ctx);
895 
896 	ctx->dev = dev;
897 	mutex_init(&ctx->lock);
898 
899 	if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) {
900 		dev_err(dev, "I2C adapter lacks SMBUS feature\n");
901 		return -EIO;
902 	}
903 
904 	if (!client->irq) {
905 		dev_err(dev, "no irq provided\n");
906 		return -EINVAL;
907 	}
908 
909 	irq_set_status_flags(client->irq, IRQ_NOAUTOEN);
910 	ret = devm_request_threaded_irq(dev, client->irq, NULL,
911 					sii9234_irq_thread,
912 					IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
913 					"sii9234", ctx);
914 	if (ret < 0)
915 		return dev_err_probe(dev, ret,
916 				     "failed to install IRQ handler\n");
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.of_node = dev->of_node;
925 	drm_bridge_add(&ctx->bridge);
926 
927 	sii9234_cable_in(ctx);
928 
929 	return 0;
930 }
931 
932 static void sii9234_remove(struct i2c_client *client)
933 {
934 	struct sii9234 *ctx = i2c_get_clientdata(client);
935 
936 	sii9234_cable_out(ctx);
937 	drm_bridge_remove(&ctx->bridge);
938 }
939 
940 static const struct of_device_id sii9234_dt_match[] = {
941 	{ .compatible = "sil,sii9234" },
942 	{ },
943 };
944 MODULE_DEVICE_TABLE(of, sii9234_dt_match);
945 
946 static const struct i2c_device_id sii9234_id[] = {
947 	{ .name = "SII9234" },
948 	{ }
949 };
950 MODULE_DEVICE_TABLE(i2c, sii9234_id);
951 
952 static struct i2c_driver sii9234_driver = {
953 	.driver = {
954 		.name	= "sii9234",
955 		.of_match_table = sii9234_dt_match,
956 	},
957 	.probe = sii9234_probe,
958 	.remove = sii9234_remove,
959 	.id_table = sii9234_id,
960 };
961 
962 module_i2c_driver(sii9234_driver);
963 MODULE_DESCRIPTION("Silicon Image SII9234 HDMI/MHL bridge driver");
964 MODULE_LICENSE("GPL");
965