1// SPDX-License-Identifier: GPL-2.0-only
2/*
3 * Copyright (c) 2016 MediaTek Inc.
4 */
5
6#include <linux/delay.h>
7#include <linux/err.h>
8#include <linux/gpio/consumer.h>
9#include <linux/i2c.h>
10#include <linux/module.h>
11#include <linux/of_graph.h>
12#include <linux/pm_runtime.h>
13#include <linux/regmap.h>
14#include <linux/regulator/consumer.h>
15
16#include <drm/display/drm_dp_aux_bus.h>
17#include <drm/display/drm_dp_helper.h>
18#include <drm/drm_atomic_state_helper.h>
19#include <drm/drm_bridge.h>
20#include <drm/drm_edid.h>
21#include <drm/drm_mipi_dsi.h>
22#include <drm/drm_of.h>
23#include <drm/drm_panel.h>
24#include <drm/drm_print.h>
25
26#define PAGE0_AUXCH_CFG3 0x76
27#define AUXCH_CFG3_RESET 0xff
28#define PAGE0_SWAUX_ADDR_7_0 0x7d
29#define PAGE0_SWAUX_ADDR_15_8 0x7e
30#define PAGE0_SWAUX_ADDR_23_16 0x7f
31#define SWAUX_ADDR_MASK GENMASK(19, 0)
32#define PAGE0_SWAUX_LENGTH 0x80
33#define SWAUX_LENGTH_MASK GENMASK(3, 0)
34#define SWAUX_NO_PAYLOAD BIT(7)
35#define PAGE0_SWAUX_WDATA 0x81
36#define PAGE0_SWAUX_RDATA 0x82
37#define PAGE0_SWAUX_CTRL 0x83
38#define SWAUX_SEND BIT(0)
39#define PAGE0_SWAUX_STATUS 0x84
40#define SWAUX_M_MASK GENMASK(4, 0)
41#define SWAUX_STATUS_MASK GENMASK(7, 5)
42#define SWAUX_STATUS_NACK (0x1 << 5)
43#define SWAUX_STATUS_DEFER (0x2 << 5)
44#define SWAUX_STATUS_ACKM (0x3 << 5)
45#define SWAUX_STATUS_INVALID (0x4 << 5)
46#define SWAUX_STATUS_I2C_NACK (0x5 << 5)
47#define SWAUX_STATUS_I2C_DEFER (0x6 << 5)
48#define SWAUX_STATUS_TIMEOUT (0x7 << 5)
49
50#define PAGE2_GPIO_H 0xa7
51#define PS_GPIO9 BIT(1)
52#define PAGE2_I2C_BYPASS 0xea
53#define I2C_BYPASS_EN 0xd0
54#define PAGE2_MCS_EN 0xf3
55#define MCS_EN BIT(0)
56
57#define PAGE3_SET_ADD 0xfe
58#define VDO_CTL_ADD 0x13
59#define VDO_DIS 0x18
60#define VDO_EN 0x1c
61
62#define NUM_MIPI_LANES 4
63
64#define COMMON_PS8640_REGMAP_CONFIG \
65 .reg_bits = 8, \
66 .val_bits = 8, \
67 .cache_type = REGCACHE_NONE
68
69/*
70 * PS8640 uses multiple addresses:
71 * page[0]: for DP control
72 * page[1]: for VIDEO Bridge
73 * page[2]: for control top
74 * page[3]: for DSI Link Control1
75 * page[4]: for MIPI Phy
76 * page[5]: for VPLL
77 * page[6]: for DSI Link Control2
78 * page[7]: for SPI ROM mapping
79 */
80enum page_addr_offset {
81 PAGE0_DP_CNTL = 0,
82 PAGE1_VDO_BDG,
83 PAGE2_TOP_CNTL,
84 PAGE3_DSI_CNTL1,
85 PAGE4_MIPI_PHY,
86 PAGE5_VPLL,
87 PAGE6_DSI_CNTL2,
88 PAGE7_SPI_CNTL,
89 MAX_DEVS
90};
91
92enum ps8640_vdo_control {
93 DISABLE = VDO_DIS,
94 ENABLE = VDO_EN,
95};
96
97struct ps8640 {
98 struct drm_bridge bridge;
99 struct drm_bridge *panel_bridge;
100 struct drm_dp_aux aux;
101 struct mipi_dsi_device *dsi;
102 struct i2c_client *page[MAX_DEVS];
103 struct regmap *regmap[MAX_DEVS];
104 struct regulator_bulk_data supplies[2];
105 struct gpio_desc *gpio_reset;
106 struct gpio_desc *gpio_powerdown;
107 struct device_link *link;
108 bool pre_enabled;
109 bool need_post_hpd_delay;
110 struct mutex aux_lock;
111};
112
113static const struct regmap_config ps8640_regmap_config[] = {
114 [PAGE0_DP_CNTL] = {
115 COMMON_PS8640_REGMAP_CONFIG,
116 .max_register = 0xbf,
117 },
118 [PAGE1_VDO_BDG] = {
119 COMMON_PS8640_REGMAP_CONFIG,
120 .max_register = 0xff,
121 },
122 [PAGE2_TOP_CNTL] = {
123 COMMON_PS8640_REGMAP_CONFIG,
124 .max_register = 0xff,
125 },
126 [PAGE3_DSI_CNTL1] = {
127 COMMON_PS8640_REGMAP_CONFIG,
128 .max_register = 0xff,
129 },
130 [PAGE4_MIPI_PHY] = {
131 COMMON_PS8640_REGMAP_CONFIG,
132 .max_register = 0xff,
133 },
134 [PAGE5_VPLL] = {
135 COMMON_PS8640_REGMAP_CONFIG,
136 .max_register = 0x7f,
137 },
138 [PAGE6_DSI_CNTL2] = {
139 COMMON_PS8640_REGMAP_CONFIG,
140 .max_register = 0xff,
141 },
142 [PAGE7_SPI_CNTL] = {
143 COMMON_PS8640_REGMAP_CONFIG,
144 .max_register = 0xff,
145 },
146};
147
148static inline struct ps8640 *bridge_to_ps8640(struct drm_bridge *e)
149{
150 return container_of(e, struct ps8640, bridge);
151}
152
153static inline struct ps8640 *aux_to_ps8640(struct drm_dp_aux *aux)
154{
155 return container_of(aux, struct ps8640, aux);
156}
157
158static int _ps8640_wait_hpd_asserted(struct ps8640 *ps_bridge, unsigned long wait_us)
159{
160 struct regmap *map = ps_bridge->regmap[PAGE2_TOP_CNTL];
161 int status;
162 int ret;
163
164 /*
165 * Apparently something about the firmware in the chip signals that
166 * HPD goes high by reporting GPIO9 as high (even though HPD isn't
167 * actually connected to GPIO9).
168 */
169 ret = regmap_read_poll_timeout(map, PAGE2_GPIO_H, status,
170 status & PS_GPIO9, 20000, wait_us);
171
172 /*
173 * The first time we see HPD go high after a reset we delay an extra
174 * 50 ms. The best guess is that the MCU is doing "stuff" during this
175 * time (maybe talking to the panel) and we don't want to interrupt it.
176 *
177 * No locking is done around "need_post_hpd_delay". If we're here we
178 * know we're holding a PM Runtime reference and the only other place
179 * that touches this is PM Runtime resume.
180 */
181 if (!ret && ps_bridge->need_post_hpd_delay) {
182 ps_bridge->need_post_hpd_delay = false;
183 msleep(msecs: 50);
184 }
185
186 return ret;
187}
188
189static int ps8640_wait_hpd_asserted(struct drm_dp_aux *aux, unsigned long wait_us)
190{
191 struct ps8640 *ps_bridge = aux_to_ps8640(aux);
192 struct device *dev = &ps_bridge->page[PAGE0_DP_CNTL]->dev;
193 int ret;
194
195 /*
196 * Note that this function is called by code that has already powered
197 * the panel. We have to power ourselves up but we don't need to worry
198 * about powering the panel.
199 */
200 pm_runtime_get_sync(dev);
201 ret = _ps8640_wait_hpd_asserted(ps_bridge, wait_us);
202 pm_runtime_mark_last_busy(dev);
203 pm_runtime_put_autosuspend(dev);
204
205 return ret;
206}
207
208static ssize_t ps8640_aux_transfer_msg(struct drm_dp_aux *aux,
209 struct drm_dp_aux_msg *msg)
210{
211 struct ps8640 *ps_bridge = aux_to_ps8640(aux);
212 struct regmap *map = ps_bridge->regmap[PAGE0_DP_CNTL];
213 struct device *dev = &ps_bridge->page[PAGE0_DP_CNTL]->dev;
214 size_t len = msg->size;
215 unsigned int data;
216 unsigned int base;
217 int ret;
218 u8 request = msg->request &
219 ~(DP_AUX_I2C_MOT | DP_AUX_I2C_WRITE_STATUS_UPDATE);
220 u8 *buf = msg->buffer;
221 u8 addr_len[PAGE0_SWAUX_LENGTH + 1 - PAGE0_SWAUX_ADDR_7_0];
222 u8 i;
223 bool is_native_aux = false;
224
225 if (len > DP_AUX_MAX_PAYLOAD_BYTES)
226 return -EINVAL;
227
228 if (msg->address & ~SWAUX_ADDR_MASK)
229 return -EINVAL;
230
231 switch (request) {
232 case DP_AUX_NATIVE_WRITE:
233 case DP_AUX_NATIVE_READ:
234 is_native_aux = true;
235 fallthrough;
236 case DP_AUX_I2C_WRITE:
237 case DP_AUX_I2C_READ:
238 break;
239 default:
240 return -EINVAL;
241 }
242
243 ret = regmap_write(map, PAGE0_AUXCH_CFG3, AUXCH_CFG3_RESET);
244 if (ret) {
245 DRM_DEV_ERROR(dev, "failed to write PAGE0_AUXCH_CFG3: %d\n",
246 ret);
247 return ret;
248 }
249
250 /* Assume it's good */
251 msg->reply = 0;
252
253 base = PAGE0_SWAUX_ADDR_7_0;
254 addr_len[PAGE0_SWAUX_ADDR_7_0 - base] = msg->address;
255 addr_len[PAGE0_SWAUX_ADDR_15_8 - base] = msg->address >> 8;
256 addr_len[PAGE0_SWAUX_ADDR_23_16 - base] = (msg->address >> 16) |
257 (msg->request << 4);
258 addr_len[PAGE0_SWAUX_LENGTH - base] = (len == 0) ? SWAUX_NO_PAYLOAD :
259 ((len - 1) & SWAUX_LENGTH_MASK);
260
261 regmap_bulk_write(map, PAGE0_SWAUX_ADDR_7_0, val: addr_len,
262 ARRAY_SIZE(addr_len));
263
264 if (len && (request == DP_AUX_NATIVE_WRITE ||
265 request == DP_AUX_I2C_WRITE)) {
266 /* Write to the internal FIFO buffer */
267 for (i = 0; i < len; i++) {
268 ret = regmap_write(map, PAGE0_SWAUX_WDATA, val: buf[i]);
269 if (ret) {
270 DRM_DEV_ERROR(dev,
271 "failed to write WDATA: %d\n",
272 ret);
273 return ret;
274 }
275 }
276 }
277
278 regmap_write(map, PAGE0_SWAUX_CTRL, SWAUX_SEND);
279
280 /* Zero delay loop because i2c transactions are slow already */
281 regmap_read_poll_timeout(map, PAGE0_SWAUX_CTRL, data,
282 !(data & SWAUX_SEND), 0, 50 * 1000);
283
284 regmap_read(map, PAGE0_SWAUX_STATUS, val: &data);
285 if (ret) {
286 DRM_DEV_ERROR(dev, "failed to read PAGE0_SWAUX_STATUS: %d\n",
287 ret);
288 return ret;
289 }
290
291 switch (data & SWAUX_STATUS_MASK) {
292 case SWAUX_STATUS_NACK:
293 case SWAUX_STATUS_I2C_NACK:
294 /*
295 * The programming guide is not clear about whether a I2C NACK
296 * would trigger SWAUX_STATUS_NACK or SWAUX_STATUS_I2C_NACK. So
297 * we handle both cases together.
298 */
299 if (is_native_aux)
300 msg->reply |= DP_AUX_NATIVE_REPLY_NACK;
301 else
302 msg->reply |= DP_AUX_I2C_REPLY_NACK;
303
304 fallthrough;
305 case SWAUX_STATUS_ACKM:
306 len = data & SWAUX_M_MASK;
307 break;
308 case SWAUX_STATUS_DEFER:
309 case SWAUX_STATUS_I2C_DEFER:
310 if (is_native_aux)
311 msg->reply |= DP_AUX_NATIVE_REPLY_DEFER;
312 else
313 msg->reply |= DP_AUX_I2C_REPLY_DEFER;
314 len = data & SWAUX_M_MASK;
315 break;
316 case SWAUX_STATUS_INVALID:
317 return -EOPNOTSUPP;
318 case SWAUX_STATUS_TIMEOUT:
319 return -ETIMEDOUT;
320 }
321
322 if (len && (request == DP_AUX_NATIVE_READ ||
323 request == DP_AUX_I2C_READ)) {
324 /* Read from the internal FIFO buffer */
325 for (i = 0; i < len; i++) {
326 ret = regmap_read(map, PAGE0_SWAUX_RDATA, val: &data);
327 if (ret) {
328 DRM_DEV_ERROR(dev,
329 "failed to read RDATA: %d\n",
330 ret);
331 return ret;
332 }
333
334 if (i < msg->size)
335 buf[i] = data;
336 }
337 }
338
339 return min(len, msg->size);
340}
341
342static ssize_t ps8640_aux_transfer(struct drm_dp_aux *aux,
343 struct drm_dp_aux_msg *msg)
344{
345 struct ps8640 *ps_bridge = aux_to_ps8640(aux);
346 struct device *dev = &ps_bridge->page[PAGE0_DP_CNTL]->dev;
347 int ret;
348
349 mutex_lock(&ps_bridge->aux_lock);
350 pm_runtime_get_sync(dev);
351 ret = _ps8640_wait_hpd_asserted(ps_bridge, wait_us: 200 * 1000);
352 if (ret) {
353 pm_runtime_put_sync_suspend(dev);
354 goto exit;
355 }
356 ret = ps8640_aux_transfer_msg(aux, msg);
357 pm_runtime_mark_last_busy(dev);
358 pm_runtime_put_autosuspend(dev);
359
360exit:
361 mutex_unlock(lock: &ps_bridge->aux_lock);
362
363 return ret;
364}
365
366static void ps8640_bridge_vdo_control(struct ps8640 *ps_bridge,
367 const enum ps8640_vdo_control ctrl)
368{
369 struct regmap *map = ps_bridge->regmap[PAGE3_DSI_CNTL1];
370 struct device *dev = &ps_bridge->page[PAGE3_DSI_CNTL1]->dev;
371 u8 vdo_ctrl_buf[] = { VDO_CTL_ADD, ctrl };
372 int ret;
373
374 ret = regmap_bulk_write(map, PAGE3_SET_ADD,
375 val: vdo_ctrl_buf, val_count: sizeof(vdo_ctrl_buf));
376
377 if (ret < 0)
378 dev_err(dev, "failed to %sable VDO: %d\n",
379 ctrl == ENABLE ? "en" : "dis", ret);
380}
381
382static int __maybe_unused ps8640_resume(struct device *dev)
383{
384 struct ps8640 *ps_bridge = dev_get_drvdata(dev);
385 int ret;
386
387 ret = regulator_bulk_enable(ARRAY_SIZE(ps_bridge->supplies),
388 consumers: ps_bridge->supplies);
389 if (ret < 0) {
390 dev_err(dev, "cannot enable regulators %d\n", ret);
391 return ret;
392 }
393
394 gpiod_set_value(desc: ps_bridge->gpio_powerdown, value: 0);
395 gpiod_set_value(desc: ps_bridge->gpio_reset, value: 1);
396 usleep_range(min: 2000, max: 2500);
397 gpiod_set_value(desc: ps_bridge->gpio_reset, value: 0);
398 /* Double reset for T4 and T5 */
399 msleep(msecs: 50);
400 gpiod_set_value(desc: ps_bridge->gpio_reset, value: 1);
401 msleep(msecs: 50);
402 gpiod_set_value(desc: ps_bridge->gpio_reset, value: 0);
403
404 /* We just reset things, so we need a delay after the first HPD */
405 ps_bridge->need_post_hpd_delay = true;
406
407 /*
408 * Mystery 200 ms delay for the "MCU to be ready". It's unclear if
409 * this is truly necessary since the MCU will already signal that
410 * things are "good to go" by signaling HPD on "gpio 9". See
411 * _ps8640_wait_hpd_asserted(). For now we'll keep this mystery delay
412 * just in case.
413 */
414 msleep(msecs: 200);
415
416 return 0;
417}
418
419static int __maybe_unused ps8640_suspend(struct device *dev)
420{
421 struct ps8640 *ps_bridge = dev_get_drvdata(dev);
422 int ret;
423
424 gpiod_set_value(desc: ps_bridge->gpio_reset, value: 1);
425 gpiod_set_value(desc: ps_bridge->gpio_powerdown, value: 1);
426 ret = regulator_bulk_disable(ARRAY_SIZE(ps_bridge->supplies),
427 consumers: ps_bridge->supplies);
428 if (ret < 0)
429 dev_err(dev, "cannot disable regulators %d\n", ret);
430
431 return ret;
432}
433
434static const struct dev_pm_ops ps8640_pm_ops = {
435 SET_RUNTIME_PM_OPS(ps8640_suspend, ps8640_resume, NULL)
436 SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
437 pm_runtime_force_resume)
438};
439
440static void ps8640_atomic_pre_enable(struct drm_bridge *bridge,
441 struct drm_bridge_state *old_bridge_state)
442{
443 struct ps8640 *ps_bridge = bridge_to_ps8640(e: bridge);
444 struct regmap *map = ps_bridge->regmap[PAGE2_TOP_CNTL];
445 struct device *dev = &ps_bridge->page[PAGE0_DP_CNTL]->dev;
446 int ret;
447
448 pm_runtime_get_sync(dev);
449 ret = _ps8640_wait_hpd_asserted(ps_bridge, wait_us: 200 * 1000);
450 if (ret < 0)
451 dev_warn(dev, "HPD didn't go high: %d\n", ret);
452
453 /*
454 * The Manufacturer Command Set (MCS) is a device dependent interface
455 * intended for factory programming of the display module default
456 * parameters. Once the display module is configured, the MCS shall be
457 * disabled by the manufacturer. Once disabled, all MCS commands are
458 * ignored by the display interface.
459 */
460
461 ret = regmap_update_bits(map, PAGE2_MCS_EN, MCS_EN, val: 0);
462 if (ret < 0)
463 dev_warn(dev, "failed write PAGE2_MCS_EN: %d\n", ret);
464
465 /* Switch access edp panel's edid through i2c */
466 ret = regmap_write(map, PAGE2_I2C_BYPASS, I2C_BYPASS_EN);
467 if (ret < 0)
468 dev_warn(dev, "failed write PAGE2_MCS_EN: %d\n", ret);
469
470 ps8640_bridge_vdo_control(ps_bridge, ctrl: ENABLE);
471
472 ps_bridge->pre_enabled = true;
473}
474
475static void ps8640_atomic_post_disable(struct drm_bridge *bridge,
476 struct drm_bridge_state *old_bridge_state)
477{
478 struct ps8640 *ps_bridge = bridge_to_ps8640(e: bridge);
479
480 ps_bridge->pre_enabled = false;
481
482 ps8640_bridge_vdo_control(ps_bridge, ctrl: DISABLE);
483
484 /*
485 * The bridge seems to expect everything to be power cycled at the
486 * disable process, so grab a lock here to make sure
487 * ps8640_aux_transfer() is not holding a runtime PM reference and
488 * preventing the bridge from suspend.
489 */
490 mutex_lock(&ps_bridge->aux_lock);
491
492 pm_runtime_put_sync_suspend(dev: &ps_bridge->page[PAGE0_DP_CNTL]->dev);
493
494 mutex_unlock(lock: &ps_bridge->aux_lock);
495}
496
497static int ps8640_bridge_attach(struct drm_bridge *bridge,
498 enum drm_bridge_attach_flags flags)
499{
500 struct ps8640 *ps_bridge = bridge_to_ps8640(e: bridge);
501 struct device *dev = &ps_bridge->page[0]->dev;
502 int ret;
503
504 if (!(flags & DRM_BRIDGE_ATTACH_NO_CONNECTOR))
505 return -EINVAL;
506
507 ps_bridge->aux.drm_dev = bridge->dev;
508 ret = drm_dp_aux_register(aux: &ps_bridge->aux);
509 if (ret) {
510 dev_err(dev, "failed to register DP AUX channel: %d\n", ret);
511 return ret;
512 }
513
514 ps_bridge->link = device_link_add(consumer: bridge->dev->dev, supplier: dev, DL_FLAG_STATELESS);
515 if (!ps_bridge->link) {
516 dev_err(dev, "failed to create device link");
517 ret = -EINVAL;
518 goto err_devlink;
519 }
520
521 /* Attach the panel-bridge to the dsi bridge */
522 ret = drm_bridge_attach(encoder: bridge->encoder, bridge: ps_bridge->panel_bridge,
523 previous: &ps_bridge->bridge, flags);
524 if (ret)
525 goto err_bridge_attach;
526
527 return 0;
528
529err_bridge_attach:
530 device_link_del(link: ps_bridge->link);
531err_devlink:
532 drm_dp_aux_unregister(aux: &ps_bridge->aux);
533
534 return ret;
535}
536
537static void ps8640_bridge_detach(struct drm_bridge *bridge)
538{
539 struct ps8640 *ps_bridge = bridge_to_ps8640(e: bridge);
540
541 drm_dp_aux_unregister(aux: &ps_bridge->aux);
542 if (ps_bridge->link)
543 device_link_del(link: ps_bridge->link);
544}
545
546static void ps8640_runtime_disable(void *data)
547{
548 pm_runtime_dont_use_autosuspend(dev: data);
549 pm_runtime_disable(dev: data);
550}
551
552static const struct drm_bridge_funcs ps8640_bridge_funcs = {
553 .attach = ps8640_bridge_attach,
554 .detach = ps8640_bridge_detach,
555 .atomic_post_disable = ps8640_atomic_post_disable,
556 .atomic_pre_enable = ps8640_atomic_pre_enable,
557 .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
558 .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
559 .atomic_reset = drm_atomic_helper_bridge_reset,
560};
561
562static int ps8640_bridge_get_dsi_resources(struct device *dev, struct ps8640 *ps_bridge)
563{
564 struct device_node *in_ep, *dsi_node;
565 struct mipi_dsi_device *dsi;
566 struct mipi_dsi_host *host;
567 const struct mipi_dsi_device_info info = { .type = "ps8640",
568 .channel = 0,
569 .node = NULL,
570 };
571
572 /* port@0 is ps8640 dsi input port */
573 in_ep = of_graph_get_endpoint_by_regs(parent: dev->of_node, port_reg: 0, reg: -1);
574 if (!in_ep)
575 return -ENODEV;
576
577 dsi_node = of_graph_get_remote_port_parent(node: in_ep);
578 of_node_put(node: in_ep);
579 if (!dsi_node)
580 return -ENODEV;
581
582 host = of_find_mipi_dsi_host_by_node(node: dsi_node);
583 of_node_put(node: dsi_node);
584 if (!host)
585 return -EPROBE_DEFER;
586
587 dsi = devm_mipi_dsi_device_register_full(dev, host, info: &info);
588 if (IS_ERR(ptr: dsi)) {
589 dev_err(dev, "failed to create dsi device\n");
590 return PTR_ERR(ptr: dsi);
591 }
592
593 ps_bridge->dsi = dsi;
594
595 dsi->host = host;
596 dsi->mode_flags = MIPI_DSI_MODE_VIDEO |
597 MIPI_DSI_MODE_VIDEO_SYNC_PULSE;
598 dsi->format = MIPI_DSI_FMT_RGB888;
599 dsi->lanes = NUM_MIPI_LANES;
600
601 return 0;
602}
603
604static int ps8640_bridge_link_panel(struct drm_dp_aux *aux)
605{
606 struct ps8640 *ps_bridge = aux_to_ps8640(aux);
607 struct device *dev = aux->dev;
608 struct device_node *np = dev->of_node;
609 int ret;
610
611 /*
612 * NOTE about returning -EPROBE_DEFER from this function: if we
613 * return an error (most relevant to -EPROBE_DEFER) it will only
614 * be passed out to ps8640_probe() if it called this directly (AKA the
615 * panel isn't under the "aux-bus" node). That should be fine because
616 * if the panel is under "aux-bus" it's guaranteed to have probed by
617 * the time this function has been called.
618 */
619
620 /* port@1 is ps8640 output port */
621 ps_bridge->panel_bridge = devm_drm_of_get_bridge(dev, node: np, port: 1, endpoint: 0);
622 if (IS_ERR(ptr: ps_bridge->panel_bridge))
623 return PTR_ERR(ptr: ps_bridge->panel_bridge);
624
625 ret = devm_drm_bridge_add(dev, bridge: &ps_bridge->bridge);
626 if (ret)
627 return ret;
628
629 return devm_mipi_dsi_attach(dev, dsi: ps_bridge->dsi);
630}
631
632static int ps8640_probe(struct i2c_client *client)
633{
634 struct device *dev = &client->dev;
635 struct ps8640 *ps_bridge;
636 int ret;
637 u32 i;
638
639 ps_bridge = devm_kzalloc(dev, size: sizeof(*ps_bridge), GFP_KERNEL);
640 if (!ps_bridge)
641 return -ENOMEM;
642
643 mutex_init(&ps_bridge->aux_lock);
644
645 ps_bridge->supplies[0].supply = "vdd12";
646 ps_bridge->supplies[1].supply = "vdd33";
647 ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(ps_bridge->supplies),
648 consumers: ps_bridge->supplies);
649 if (ret)
650 return ret;
651
652 ps_bridge->gpio_powerdown = devm_gpiod_get(dev: &client->dev, con_id: "powerdown",
653 flags: GPIOD_OUT_HIGH);
654 if (IS_ERR(ptr: ps_bridge->gpio_powerdown))
655 return PTR_ERR(ptr: ps_bridge->gpio_powerdown);
656
657 /*
658 * Assert the reset to avoid the bridge being initialized prematurely
659 */
660 ps_bridge->gpio_reset = devm_gpiod_get(dev: &client->dev, con_id: "reset",
661 flags: GPIOD_OUT_HIGH);
662 if (IS_ERR(ptr: ps_bridge->gpio_reset))
663 return PTR_ERR(ptr: ps_bridge->gpio_reset);
664
665 ps_bridge->bridge.funcs = &ps8640_bridge_funcs;
666 ps_bridge->bridge.of_node = dev->of_node;
667 ps_bridge->bridge.type = DRM_MODE_CONNECTOR_eDP;
668
669 /*
670 * Get MIPI DSI resources early. These can return -EPROBE_DEFER so
671 * we want to get them out of the way sooner.
672 */
673 ret = ps8640_bridge_get_dsi_resources(dev: &client->dev, ps_bridge);
674 if (ret)
675 return ret;
676
677 ps_bridge->page[PAGE0_DP_CNTL] = client;
678
679 ps_bridge->regmap[PAGE0_DP_CNTL] = devm_regmap_init_i2c(client, ps8640_regmap_config);
680 if (IS_ERR(ptr: ps_bridge->regmap[PAGE0_DP_CNTL]))
681 return PTR_ERR(ptr: ps_bridge->regmap[PAGE0_DP_CNTL]);
682
683 for (i = 1; i < ARRAY_SIZE(ps_bridge->page); i++) {
684 ps_bridge->page[i] = devm_i2c_new_dummy_device(dev: &client->dev,
685 adap: client->adapter,
686 address: client->addr + i);
687 if (IS_ERR(ptr: ps_bridge->page[i]))
688 return PTR_ERR(ptr: ps_bridge->page[i]);
689
690 ps_bridge->regmap[i] = devm_regmap_init_i2c(ps_bridge->page[i],
691 ps8640_regmap_config + i);
692 if (IS_ERR(ptr: ps_bridge->regmap[i]))
693 return PTR_ERR(ptr: ps_bridge->regmap[i]);
694 }
695
696 i2c_set_clientdata(client, data: ps_bridge);
697
698 ps_bridge->aux.name = "parade-ps8640-aux";
699 ps_bridge->aux.dev = dev;
700 ps_bridge->aux.transfer = ps8640_aux_transfer;
701 ps_bridge->aux.wait_hpd_asserted = ps8640_wait_hpd_asserted;
702 drm_dp_aux_init(aux: &ps_bridge->aux);
703
704 pm_runtime_enable(dev);
705 /*
706 * Powering on ps8640 takes ~300ms. To avoid wasting time on power
707 * cycling ps8640 too often, set autosuspend_delay to 2000ms to ensure
708 * the bridge wouldn't suspend in between each _aux_transfer_msg() call
709 * during EDID read (~20ms in my experiment) and in between the last
710 * _aux_transfer_msg() call during EDID read and the _pre_enable() call
711 * (~100ms in my experiment).
712 */
713 pm_runtime_set_autosuspend_delay(dev, delay: 2000);
714 pm_runtime_use_autosuspend(dev);
715 pm_suspend_ignore_children(dev, enable: true);
716 ret = devm_add_action_or_reset(dev, ps8640_runtime_disable, dev);
717 if (ret)
718 return ret;
719
720 ret = devm_of_dp_aux_populate_bus(aux: &ps_bridge->aux, done_probing: ps8640_bridge_link_panel);
721
722 /*
723 * If devm_of_dp_aux_populate_bus() returns -ENODEV then it's up to
724 * usa to call ps8640_bridge_link_panel() directly. NOTE: in this case
725 * the function is allowed to -EPROBE_DEFER.
726 */
727 if (ret == -ENODEV)
728 return ps8640_bridge_link_panel(aux: &ps_bridge->aux);
729
730 return ret;
731}
732
733static const struct of_device_id ps8640_match[] = {
734 { .compatible = "parade,ps8640" },
735 { }
736};
737MODULE_DEVICE_TABLE(of, ps8640_match);
738
739static struct i2c_driver ps8640_driver = {
740 .probe = ps8640_probe,
741 .driver = {
742 .name = "ps8640",
743 .of_match_table = ps8640_match,
744 .pm = &ps8640_pm_ops,
745 },
746};
747module_i2c_driver(ps8640_driver);
748
749MODULE_AUTHOR("Jitao Shi <jitao.shi@mediatek.com>");
750MODULE_AUTHOR("CK Hu <ck.hu@mediatek.com>");
751MODULE_AUTHOR("Enric Balletbo i Serra <enric.balletbo@collabora.com>");
752MODULE_DESCRIPTION("PARADE ps8640 DSI-eDP converter driver");
753MODULE_LICENSE("GPL v2");
754

source code of linux/drivers/gpu/drm/bridge/parade-ps8640.c