1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2013 NVIDIA Corporation
4 */
5
6 #include <linux/clk.h>
7 #include <linux/delay.h>
8 #include <linux/interrupt.h>
9 #include <linux/io.h>
10 #include <linux/module.h>
11 #include <linux/of.h>
12 #include <linux/pinctrl/pinconf-generic.h>
13 #include <linux/pinctrl/pinctrl.h>
14 #include <linux/pinctrl/pinmux.h>
15 #include <linux/platform_device.h>
16 #include <linux/pm_runtime.h>
17 #include <linux/regulator/consumer.h>
18 #include <linux/reset.h>
19 #include <linux/workqueue.h>
20
21 #include <drm/display/drm_dp_helper.h>
22 #include <drm/display/drm_dp_aux_bus.h>
23 #include <drm/drm_panel.h>
24
25 #include "dp.h"
26 #include "dpaux.h"
27 #include "drm.h"
28 #include "trace.h"
29
30 static DEFINE_MUTEX(dpaux_lock);
31 static LIST_HEAD(dpaux_list);
32
33 struct tegra_dpaux_soc {
34 unsigned int cmh;
35 unsigned int drvz;
36 unsigned int drvi;
37 };
38
39 struct tegra_dpaux {
40 struct drm_dp_aux aux;
41 struct device *dev;
42
43 const struct tegra_dpaux_soc *soc;
44
45 void __iomem *regs;
46 int irq;
47
48 struct tegra_output *output;
49
50 struct reset_control *rst;
51 struct clk *clk_parent;
52 struct clk *clk;
53
54 struct regulator *vdd;
55
56 struct completion complete;
57 struct work_struct work;
58 struct list_head list;
59
60 #ifdef CONFIG_GENERIC_PINCONF
61 struct pinctrl_dev *pinctrl;
62 struct pinctrl_desc desc;
63 #endif
64 };
65
to_dpaux(struct drm_dp_aux * aux)66 static inline struct tegra_dpaux *to_dpaux(struct drm_dp_aux *aux)
67 {
68 return container_of(aux, struct tegra_dpaux, aux);
69 }
70
work_to_dpaux(struct work_struct * work)71 static inline struct tegra_dpaux *work_to_dpaux(struct work_struct *work)
72 {
73 return container_of(work, struct tegra_dpaux, work);
74 }
75
tegra_dpaux_readl(struct tegra_dpaux * dpaux,unsigned int offset)76 static inline u32 tegra_dpaux_readl(struct tegra_dpaux *dpaux,
77 unsigned int offset)
78 {
79 u32 value = readl(dpaux->regs + (offset << 2));
80
81 trace_dpaux_readl(dpaux->dev, offset, value);
82
83 return value;
84 }
85
tegra_dpaux_writel(struct tegra_dpaux * dpaux,u32 value,unsigned int offset)86 static inline void tegra_dpaux_writel(struct tegra_dpaux *dpaux,
87 u32 value, unsigned int offset)
88 {
89 trace_dpaux_writel(dpaux->dev, offset, value);
90 writel(value, dpaux->regs + (offset << 2));
91 }
92
tegra_dpaux_write_fifo(struct tegra_dpaux * dpaux,const u8 * buffer,size_t size)93 static void tegra_dpaux_write_fifo(struct tegra_dpaux *dpaux, const u8 *buffer,
94 size_t size)
95 {
96 size_t i, j;
97
98 for (i = 0; i < DIV_ROUND_UP(size, 4); i++) {
99 size_t num = min_t(size_t, size - i * 4, 4);
100 u32 value = 0;
101
102 for (j = 0; j < num; j++)
103 value |= buffer[i * 4 + j] << (j * 8);
104
105 tegra_dpaux_writel(dpaux, value, DPAUX_DP_AUXDATA_WRITE(i));
106 }
107 }
108
tegra_dpaux_read_fifo(struct tegra_dpaux * dpaux,u8 * buffer,size_t size)109 static void tegra_dpaux_read_fifo(struct tegra_dpaux *dpaux, u8 *buffer,
110 size_t size)
111 {
112 size_t i, j;
113
114 for (i = 0; i < DIV_ROUND_UP(size, 4); i++) {
115 size_t num = min_t(size_t, size - i * 4, 4);
116 u32 value;
117
118 value = tegra_dpaux_readl(dpaux, DPAUX_DP_AUXDATA_READ(i));
119
120 for (j = 0; j < num; j++)
121 buffer[i * 4 + j] = value >> (j * 8);
122 }
123 }
124
tegra_dpaux_transfer(struct drm_dp_aux * aux,struct drm_dp_aux_msg * msg)125 static ssize_t tegra_dpaux_transfer(struct drm_dp_aux *aux,
126 struct drm_dp_aux_msg *msg)
127 {
128 unsigned long timeout = msecs_to_jiffies(250);
129 struct tegra_dpaux *dpaux = to_dpaux(aux);
130 unsigned long status;
131 ssize_t ret = 0;
132 u8 reply = 0;
133 u32 value;
134
135 /* Tegra has 4x4 byte DP AUX transmit and receive FIFOs. */
136 if (msg->size > 16)
137 return -EINVAL;
138
139 /*
140 * Allow zero-sized messages only for I2C, in which case they specify
141 * address-only transactions.
142 */
143 if (msg->size < 1) {
144 switch (msg->request & ~DP_AUX_I2C_MOT) {
145 case DP_AUX_I2C_WRITE_STATUS_UPDATE:
146 case DP_AUX_I2C_WRITE:
147 case DP_AUX_I2C_READ:
148 value = DPAUX_DP_AUXCTL_CMD_ADDRESS_ONLY;
149 break;
150
151 default:
152 return -EINVAL;
153 }
154 } else {
155 /* For non-zero-sized messages, set the CMDLEN field. */
156 value = DPAUX_DP_AUXCTL_CMDLEN(msg->size - 1);
157 }
158
159 switch (msg->request & ~DP_AUX_I2C_MOT) {
160 case DP_AUX_I2C_WRITE:
161 if (msg->request & DP_AUX_I2C_MOT)
162 value |= DPAUX_DP_AUXCTL_CMD_MOT_WR;
163 else
164 value |= DPAUX_DP_AUXCTL_CMD_I2C_WR;
165
166 break;
167
168 case DP_AUX_I2C_READ:
169 if (msg->request & DP_AUX_I2C_MOT)
170 value |= DPAUX_DP_AUXCTL_CMD_MOT_RD;
171 else
172 value |= DPAUX_DP_AUXCTL_CMD_I2C_RD;
173
174 break;
175
176 case DP_AUX_I2C_WRITE_STATUS_UPDATE:
177 if (msg->request & DP_AUX_I2C_MOT)
178 value |= DPAUX_DP_AUXCTL_CMD_MOT_RQ;
179 else
180 value |= DPAUX_DP_AUXCTL_CMD_I2C_RQ;
181
182 break;
183
184 case DP_AUX_NATIVE_WRITE:
185 value |= DPAUX_DP_AUXCTL_CMD_AUX_WR;
186 break;
187
188 case DP_AUX_NATIVE_READ:
189 value |= DPAUX_DP_AUXCTL_CMD_AUX_RD;
190 break;
191
192 default:
193 return -EINVAL;
194 }
195
196 tegra_dpaux_writel(dpaux, msg->address, DPAUX_DP_AUXADDR);
197 tegra_dpaux_writel(dpaux, value, DPAUX_DP_AUXCTL);
198
199 if ((msg->request & DP_AUX_I2C_READ) == 0) {
200 tegra_dpaux_write_fifo(dpaux, msg->buffer, msg->size);
201 ret = msg->size;
202 }
203
204 /* start transaction */
205 value = tegra_dpaux_readl(dpaux, DPAUX_DP_AUXCTL);
206 value |= DPAUX_DP_AUXCTL_TRANSACTREQ;
207 tegra_dpaux_writel(dpaux, value, DPAUX_DP_AUXCTL);
208
209 status = wait_for_completion_timeout(&dpaux->complete, timeout);
210 if (!status)
211 return -ETIMEDOUT;
212
213 /* read status and clear errors */
214 value = tegra_dpaux_readl(dpaux, DPAUX_DP_AUXSTAT);
215 tegra_dpaux_writel(dpaux, 0xf00, DPAUX_DP_AUXSTAT);
216
217 if (value & DPAUX_DP_AUXSTAT_TIMEOUT_ERROR)
218 return -ETIMEDOUT;
219
220 if ((value & DPAUX_DP_AUXSTAT_RX_ERROR) ||
221 (value & DPAUX_DP_AUXSTAT_SINKSTAT_ERROR) ||
222 (value & DPAUX_DP_AUXSTAT_NO_STOP_ERROR))
223 return -EIO;
224
225 switch ((value & DPAUX_DP_AUXSTAT_REPLY_TYPE_MASK) >> 16) {
226 case 0x00:
227 reply = DP_AUX_NATIVE_REPLY_ACK;
228 break;
229
230 case 0x01:
231 reply = DP_AUX_NATIVE_REPLY_NACK;
232 break;
233
234 case 0x02:
235 reply = DP_AUX_NATIVE_REPLY_DEFER;
236 break;
237
238 case 0x04:
239 reply = DP_AUX_I2C_REPLY_NACK;
240 break;
241
242 case 0x08:
243 reply = DP_AUX_I2C_REPLY_DEFER;
244 break;
245 }
246
247 if ((msg->size > 0) && (msg->reply == DP_AUX_NATIVE_REPLY_ACK)) {
248 if (msg->request & DP_AUX_I2C_READ) {
249 size_t count = value & DPAUX_DP_AUXSTAT_REPLY_MASK;
250
251 /*
252 * There might be a smarter way to do this, but since
253 * the DP helpers will already retry transactions for
254 * an -EBUSY return value, simply reuse that instead.
255 */
256 if (count != msg->size) {
257 ret = -EBUSY;
258 goto out;
259 }
260
261 tegra_dpaux_read_fifo(dpaux, msg->buffer, count);
262 ret = count;
263 }
264 }
265
266 msg->reply = reply;
267
268 out:
269 return ret;
270 }
271
tegra_dpaux_hotplug(struct work_struct * work)272 static void tegra_dpaux_hotplug(struct work_struct *work)
273 {
274 struct tegra_dpaux *dpaux = work_to_dpaux(work);
275
276 if (dpaux->output)
277 drm_helper_hpd_irq_event(dpaux->output->connector.dev);
278 }
279
tegra_dpaux_irq(int irq,void * data)280 static irqreturn_t tegra_dpaux_irq(int irq, void *data)
281 {
282 struct tegra_dpaux *dpaux = data;
283 u32 value;
284
285 /* clear interrupts */
286 value = tegra_dpaux_readl(dpaux, DPAUX_INTR_AUX);
287 tegra_dpaux_writel(dpaux, value, DPAUX_INTR_AUX);
288
289 if (value & (DPAUX_INTR_PLUG_EVENT | DPAUX_INTR_UNPLUG_EVENT))
290 schedule_work(&dpaux->work);
291
292 if (value & DPAUX_INTR_IRQ_EVENT) {
293 /* TODO: handle this */
294 }
295
296 if (value & DPAUX_INTR_AUX_DONE)
297 complete(&dpaux->complete);
298
299 return IRQ_HANDLED;
300 }
301
302 enum tegra_dpaux_functions {
303 DPAUX_PADCTL_FUNC_AUX,
304 DPAUX_PADCTL_FUNC_I2C,
305 DPAUX_PADCTL_FUNC_OFF,
306 };
307
tegra_dpaux_pad_power_down(struct tegra_dpaux * dpaux)308 static void tegra_dpaux_pad_power_down(struct tegra_dpaux *dpaux)
309 {
310 u32 value = tegra_dpaux_readl(dpaux, DPAUX_HYBRID_SPARE);
311
312 value |= DPAUX_HYBRID_SPARE_PAD_POWER_DOWN;
313
314 tegra_dpaux_writel(dpaux, value, DPAUX_HYBRID_SPARE);
315 }
316
tegra_dpaux_pad_power_up(struct tegra_dpaux * dpaux)317 static void tegra_dpaux_pad_power_up(struct tegra_dpaux *dpaux)
318 {
319 u32 value = tegra_dpaux_readl(dpaux, DPAUX_HYBRID_SPARE);
320
321 value &= ~DPAUX_HYBRID_SPARE_PAD_POWER_DOWN;
322
323 tegra_dpaux_writel(dpaux, value, DPAUX_HYBRID_SPARE);
324 }
325
tegra_dpaux_pad_config(struct tegra_dpaux * dpaux,unsigned function)326 static int tegra_dpaux_pad_config(struct tegra_dpaux *dpaux, unsigned function)
327 {
328 u32 value;
329
330 switch (function) {
331 case DPAUX_PADCTL_FUNC_AUX:
332 value = DPAUX_HYBRID_PADCTL_AUX_CMH(dpaux->soc->cmh) |
333 DPAUX_HYBRID_PADCTL_AUX_DRVZ(dpaux->soc->drvz) |
334 DPAUX_HYBRID_PADCTL_AUX_DRVI(dpaux->soc->drvi) |
335 DPAUX_HYBRID_PADCTL_AUX_INPUT_RCV |
336 DPAUX_HYBRID_PADCTL_MODE_AUX;
337 break;
338
339 case DPAUX_PADCTL_FUNC_I2C:
340 value = DPAUX_HYBRID_PADCTL_I2C_SDA_INPUT_RCV |
341 DPAUX_HYBRID_PADCTL_I2C_SCL_INPUT_RCV |
342 DPAUX_HYBRID_PADCTL_AUX_CMH(dpaux->soc->cmh) |
343 DPAUX_HYBRID_PADCTL_AUX_DRVZ(dpaux->soc->drvz) |
344 DPAUX_HYBRID_PADCTL_AUX_DRVI(dpaux->soc->drvi) |
345 DPAUX_HYBRID_PADCTL_MODE_I2C;
346 break;
347
348 case DPAUX_PADCTL_FUNC_OFF:
349 tegra_dpaux_pad_power_down(dpaux);
350 return 0;
351
352 default:
353 return -ENOTSUPP;
354 }
355
356 tegra_dpaux_writel(dpaux, value, DPAUX_HYBRID_PADCTL);
357 tegra_dpaux_pad_power_up(dpaux);
358
359 return 0;
360 }
361
362 #ifdef CONFIG_GENERIC_PINCONF
363 static const struct pinctrl_pin_desc tegra_dpaux_pins[] = {
364 PINCTRL_PIN(0, "DP_AUX_CHx_P"),
365 PINCTRL_PIN(1, "DP_AUX_CHx_N"),
366 };
367
368 static const unsigned tegra_dpaux_pin_numbers[] = { 0, 1 };
369
370 static const char * const tegra_dpaux_groups[] = {
371 "dpaux-io",
372 };
373
374 static const char * const tegra_dpaux_functions[] = {
375 "aux",
376 "i2c",
377 "off",
378 };
379
tegra_dpaux_get_groups_count(struct pinctrl_dev * pinctrl)380 static int tegra_dpaux_get_groups_count(struct pinctrl_dev *pinctrl)
381 {
382 return ARRAY_SIZE(tegra_dpaux_groups);
383 }
384
tegra_dpaux_get_group_name(struct pinctrl_dev * pinctrl,unsigned int group)385 static const char *tegra_dpaux_get_group_name(struct pinctrl_dev *pinctrl,
386 unsigned int group)
387 {
388 return tegra_dpaux_groups[group];
389 }
390
tegra_dpaux_get_group_pins(struct pinctrl_dev * pinctrl,unsigned group,const unsigned ** pins,unsigned * num_pins)391 static int tegra_dpaux_get_group_pins(struct pinctrl_dev *pinctrl,
392 unsigned group, const unsigned **pins,
393 unsigned *num_pins)
394 {
395 *pins = tegra_dpaux_pin_numbers;
396 *num_pins = ARRAY_SIZE(tegra_dpaux_pin_numbers);
397
398 return 0;
399 }
400
401 static const struct pinctrl_ops tegra_dpaux_pinctrl_ops = {
402 .get_groups_count = tegra_dpaux_get_groups_count,
403 .get_group_name = tegra_dpaux_get_group_name,
404 .get_group_pins = tegra_dpaux_get_group_pins,
405 .dt_node_to_map = pinconf_generic_dt_node_to_map_group,
406 .dt_free_map = pinconf_generic_dt_free_map,
407 };
408
tegra_dpaux_get_functions_count(struct pinctrl_dev * pinctrl)409 static int tegra_dpaux_get_functions_count(struct pinctrl_dev *pinctrl)
410 {
411 return ARRAY_SIZE(tegra_dpaux_functions);
412 }
413
tegra_dpaux_get_function_name(struct pinctrl_dev * pinctrl,unsigned int function)414 static const char *tegra_dpaux_get_function_name(struct pinctrl_dev *pinctrl,
415 unsigned int function)
416 {
417 return tegra_dpaux_functions[function];
418 }
419
tegra_dpaux_get_function_groups(struct pinctrl_dev * pinctrl,unsigned int function,const char * const ** groups,unsigned * const num_groups)420 static int tegra_dpaux_get_function_groups(struct pinctrl_dev *pinctrl,
421 unsigned int function,
422 const char * const **groups,
423 unsigned * const num_groups)
424 {
425 *num_groups = ARRAY_SIZE(tegra_dpaux_groups);
426 *groups = tegra_dpaux_groups;
427
428 return 0;
429 }
430
tegra_dpaux_set_mux(struct pinctrl_dev * pinctrl,unsigned int function,unsigned int group)431 static int tegra_dpaux_set_mux(struct pinctrl_dev *pinctrl,
432 unsigned int function, unsigned int group)
433 {
434 struct tegra_dpaux *dpaux = pinctrl_dev_get_drvdata(pinctrl);
435
436 return tegra_dpaux_pad_config(dpaux, function);
437 }
438
439 static const struct pinmux_ops tegra_dpaux_pinmux_ops = {
440 .get_functions_count = tegra_dpaux_get_functions_count,
441 .get_function_name = tegra_dpaux_get_function_name,
442 .get_function_groups = tegra_dpaux_get_function_groups,
443 .set_mux = tegra_dpaux_set_mux,
444 };
445 #endif
446
tegra_dpaux_probe(struct platform_device * pdev)447 static int tegra_dpaux_probe(struct platform_device *pdev)
448 {
449 struct tegra_dpaux *dpaux;
450 u32 value;
451 int err;
452
453 dpaux = devm_kzalloc(&pdev->dev, sizeof(*dpaux), GFP_KERNEL);
454 if (!dpaux)
455 return -ENOMEM;
456
457 dpaux->soc = of_device_get_match_data(&pdev->dev);
458 INIT_WORK(&dpaux->work, tegra_dpaux_hotplug);
459 init_completion(&dpaux->complete);
460 INIT_LIST_HEAD(&dpaux->list);
461 dpaux->dev = &pdev->dev;
462
463 dpaux->regs = devm_platform_ioremap_resource(pdev, 0);
464 if (IS_ERR(dpaux->regs))
465 return PTR_ERR(dpaux->regs);
466
467 dpaux->irq = platform_get_irq(pdev, 0);
468 if (dpaux->irq < 0)
469 return dpaux->irq;
470
471 if (!pdev->dev.pm_domain) {
472 dpaux->rst = devm_reset_control_get(&pdev->dev, "dpaux");
473 if (IS_ERR(dpaux->rst)) {
474 dev_err(&pdev->dev,
475 "failed to get reset control: %ld\n",
476 PTR_ERR(dpaux->rst));
477 return PTR_ERR(dpaux->rst);
478 }
479 }
480
481 dpaux->clk = devm_clk_get(&pdev->dev, NULL);
482 if (IS_ERR(dpaux->clk)) {
483 dev_err(&pdev->dev, "failed to get module clock: %ld\n",
484 PTR_ERR(dpaux->clk));
485 return PTR_ERR(dpaux->clk);
486 }
487
488 dpaux->clk_parent = devm_clk_get(&pdev->dev, "parent");
489 if (IS_ERR(dpaux->clk_parent)) {
490 dev_err(&pdev->dev, "failed to get parent clock: %ld\n",
491 PTR_ERR(dpaux->clk_parent));
492 return PTR_ERR(dpaux->clk_parent);
493 }
494
495 err = clk_set_rate(dpaux->clk_parent, 270000000);
496 if (err < 0) {
497 dev_err(&pdev->dev, "failed to set clock to 270 MHz: %d\n",
498 err);
499 return err;
500 }
501
502 dpaux->vdd = devm_regulator_get_optional(&pdev->dev, "vdd");
503 if (IS_ERR(dpaux->vdd)) {
504 if (PTR_ERR(dpaux->vdd) != -ENODEV) {
505 if (PTR_ERR(dpaux->vdd) != -EPROBE_DEFER)
506 dev_err(&pdev->dev,
507 "failed to get VDD supply: %ld\n",
508 PTR_ERR(dpaux->vdd));
509
510 return PTR_ERR(dpaux->vdd);
511 }
512
513 dpaux->vdd = NULL;
514 }
515
516 platform_set_drvdata(pdev, dpaux);
517 pm_runtime_enable(&pdev->dev);
518 pm_runtime_get_sync(&pdev->dev);
519
520 err = devm_request_irq(dpaux->dev, dpaux->irq, tegra_dpaux_irq, 0,
521 dev_name(dpaux->dev), dpaux);
522 if (err < 0) {
523 dev_err(dpaux->dev, "failed to request IRQ#%u: %d\n",
524 dpaux->irq, err);
525 goto err_pm_disable;
526 }
527
528 disable_irq(dpaux->irq);
529
530 dpaux->aux.transfer = tegra_dpaux_transfer;
531 dpaux->aux.dev = &pdev->dev;
532
533 drm_dp_aux_init(&dpaux->aux);
534
535 /*
536 * Assume that by default the DPAUX/I2C pads will be used for HDMI,
537 * so power them up and configure them in I2C mode.
538 *
539 * The DPAUX code paths reconfigure the pads in AUX mode, but there
540 * is no possibility to perform the I2C mode configuration in the
541 * HDMI path.
542 */
543 err = tegra_dpaux_pad_config(dpaux, DPAUX_PADCTL_FUNC_I2C);
544 if (err < 0)
545 goto err_pm_disable;
546
547 #ifdef CONFIG_GENERIC_PINCONF
548 dpaux->desc.name = dev_name(&pdev->dev);
549 dpaux->desc.pins = tegra_dpaux_pins;
550 dpaux->desc.npins = ARRAY_SIZE(tegra_dpaux_pins);
551 dpaux->desc.pctlops = &tegra_dpaux_pinctrl_ops;
552 dpaux->desc.pmxops = &tegra_dpaux_pinmux_ops;
553 dpaux->desc.owner = THIS_MODULE;
554
555 dpaux->pinctrl = devm_pinctrl_register(&pdev->dev, &dpaux->desc, dpaux);
556 if (IS_ERR(dpaux->pinctrl)) {
557 dev_err(&pdev->dev, "failed to register pincontrol\n");
558 err = PTR_ERR(dpaux->pinctrl);
559 goto err_pm_disable;
560 }
561 #endif
562 /* enable and clear all interrupts */
563 value = DPAUX_INTR_AUX_DONE | DPAUX_INTR_IRQ_EVENT |
564 DPAUX_INTR_UNPLUG_EVENT | DPAUX_INTR_PLUG_EVENT;
565 tegra_dpaux_writel(dpaux, value, DPAUX_INTR_EN_AUX);
566 tegra_dpaux_writel(dpaux, value, DPAUX_INTR_AUX);
567
568 mutex_lock(&dpaux_lock);
569 list_add_tail(&dpaux->list, &dpaux_list);
570 mutex_unlock(&dpaux_lock);
571
572 err = devm_of_dp_aux_populate_ep_devices(&dpaux->aux);
573 if (err < 0) {
574 dev_err(dpaux->dev, "failed to populate AUX bus: %d\n", err);
575 goto err_pm_disable;
576 }
577
578 return 0;
579
580 err_pm_disable:
581 pm_runtime_put_sync(&pdev->dev);
582 pm_runtime_disable(&pdev->dev);
583 return err;
584 }
585
tegra_dpaux_remove(struct platform_device * pdev)586 static void tegra_dpaux_remove(struct platform_device *pdev)
587 {
588 struct tegra_dpaux *dpaux = platform_get_drvdata(pdev);
589
590 cancel_work_sync(&dpaux->work);
591
592 /* make sure pads are powered down when not in use */
593 tegra_dpaux_pad_power_down(dpaux);
594
595 pm_runtime_put_sync(&pdev->dev);
596 pm_runtime_disable(&pdev->dev);
597
598 mutex_lock(&dpaux_lock);
599 list_del(&dpaux->list);
600 mutex_unlock(&dpaux_lock);
601 }
602
tegra_dpaux_suspend(struct device * dev)603 static int tegra_dpaux_suspend(struct device *dev)
604 {
605 struct tegra_dpaux *dpaux = dev_get_drvdata(dev);
606 int err = 0;
607
608 if (dpaux->rst) {
609 err = reset_control_assert(dpaux->rst);
610 if (err < 0) {
611 dev_err(dev, "failed to assert reset: %d\n", err);
612 return err;
613 }
614 }
615
616 usleep_range(1000, 2000);
617
618 clk_disable_unprepare(dpaux->clk_parent);
619 clk_disable_unprepare(dpaux->clk);
620
621 return err;
622 }
623
tegra_dpaux_resume(struct device * dev)624 static int tegra_dpaux_resume(struct device *dev)
625 {
626 struct tegra_dpaux *dpaux = dev_get_drvdata(dev);
627 int err;
628
629 err = clk_prepare_enable(dpaux->clk);
630 if (err < 0) {
631 dev_err(dev, "failed to enable clock: %d\n", err);
632 return err;
633 }
634
635 err = clk_prepare_enable(dpaux->clk_parent);
636 if (err < 0) {
637 dev_err(dev, "failed to enable parent clock: %d\n", err);
638 goto disable_clk;
639 }
640
641 usleep_range(1000, 2000);
642
643 if (dpaux->rst) {
644 err = reset_control_deassert(dpaux->rst);
645 if (err < 0) {
646 dev_err(dev, "failed to deassert reset: %d\n", err);
647 goto disable_parent;
648 }
649
650 usleep_range(1000, 2000);
651 }
652
653 return 0;
654
655 disable_parent:
656 clk_disable_unprepare(dpaux->clk_parent);
657 disable_clk:
658 clk_disable_unprepare(dpaux->clk);
659 return err;
660 }
661
662 static const struct dev_pm_ops tegra_dpaux_pm_ops = {
663 RUNTIME_PM_OPS(tegra_dpaux_suspend, tegra_dpaux_resume, NULL)
664 };
665
666 static const struct tegra_dpaux_soc tegra124_dpaux_soc = {
667 .cmh = 0x02,
668 .drvz = 0x04,
669 .drvi = 0x18,
670 };
671
672 static const struct tegra_dpaux_soc tegra210_dpaux_soc = {
673 .cmh = 0x02,
674 .drvz = 0x04,
675 .drvi = 0x30,
676 };
677
678 static const struct tegra_dpaux_soc tegra194_dpaux_soc = {
679 .cmh = 0x02,
680 .drvz = 0x04,
681 .drvi = 0x2c,
682 };
683
684 static const struct of_device_id tegra_dpaux_of_match[] = {
685 { .compatible = "nvidia,tegra194-dpaux", .data = &tegra194_dpaux_soc },
686 { .compatible = "nvidia,tegra186-dpaux", .data = &tegra210_dpaux_soc },
687 { .compatible = "nvidia,tegra210-dpaux", .data = &tegra210_dpaux_soc },
688 { .compatible = "nvidia,tegra124-dpaux", .data = &tegra124_dpaux_soc },
689 { },
690 };
691 MODULE_DEVICE_TABLE(of, tegra_dpaux_of_match);
692
693 struct platform_driver tegra_dpaux_driver = {
694 .driver = {
695 .name = "tegra-dpaux",
696 .of_match_table = tegra_dpaux_of_match,
697 .pm = pm_ptr(&tegra_dpaux_pm_ops),
698 },
699 .probe = tegra_dpaux_probe,
700 .remove = tegra_dpaux_remove,
701 };
702
drm_dp_aux_find_by_of_node(struct device_node * np)703 struct drm_dp_aux *drm_dp_aux_find_by_of_node(struct device_node *np)
704 {
705 struct tegra_dpaux *dpaux;
706
707 mutex_lock(&dpaux_lock);
708
709 list_for_each_entry(dpaux, &dpaux_list, list)
710 if (np == dpaux->dev->of_node) {
711 mutex_unlock(&dpaux_lock);
712 return &dpaux->aux;
713 }
714
715 mutex_unlock(&dpaux_lock);
716
717 return NULL;
718 }
719
drm_dp_aux_attach(struct drm_dp_aux * aux,struct tegra_output * output)720 int drm_dp_aux_attach(struct drm_dp_aux *aux, struct tegra_output *output)
721 {
722 struct tegra_dpaux *dpaux = to_dpaux(aux);
723 unsigned long timeout;
724 int err;
725
726 aux->drm_dev = output->connector.dev;
727 err = drm_dp_aux_register(aux);
728 if (err < 0)
729 return err;
730
731 output->connector.polled = DRM_CONNECTOR_POLL_HPD;
732 dpaux->output = output;
733
734 if (output->panel) {
735 enum drm_connector_status status;
736
737 if (dpaux->vdd) {
738 err = regulator_enable(dpaux->vdd);
739 if (err < 0)
740 return err;
741 }
742
743 timeout = jiffies + msecs_to_jiffies(250);
744
745 while (time_before(jiffies, timeout)) {
746 status = drm_dp_aux_detect(aux);
747
748 if (status == connector_status_connected)
749 break;
750
751 usleep_range(1000, 2000);
752 }
753
754 if (status != connector_status_connected)
755 return -ETIMEDOUT;
756 }
757
758 enable_irq(dpaux->irq);
759 return 0;
760 }
761
drm_dp_aux_detach(struct drm_dp_aux * aux)762 int drm_dp_aux_detach(struct drm_dp_aux *aux)
763 {
764 struct tegra_dpaux *dpaux = to_dpaux(aux);
765 unsigned long timeout;
766 int err;
767
768 drm_dp_aux_unregister(aux);
769 disable_irq(dpaux->irq);
770
771 if (dpaux->output->panel) {
772 enum drm_connector_status status;
773
774 if (dpaux->vdd) {
775 err = regulator_disable(dpaux->vdd);
776 if (err < 0)
777 return err;
778 }
779
780 timeout = jiffies + msecs_to_jiffies(250);
781
782 while (time_before(jiffies, timeout)) {
783 status = drm_dp_aux_detect(aux);
784
785 if (status == connector_status_disconnected)
786 break;
787
788 usleep_range(1000, 2000);
789 }
790
791 if (status != connector_status_disconnected)
792 return -ETIMEDOUT;
793
794 dpaux->output = NULL;
795 }
796
797 return 0;
798 }
799
drm_dp_aux_detect(struct drm_dp_aux * aux)800 enum drm_connector_status drm_dp_aux_detect(struct drm_dp_aux *aux)
801 {
802 struct tegra_dpaux *dpaux = to_dpaux(aux);
803 u32 value;
804
805 value = tegra_dpaux_readl(dpaux, DPAUX_DP_AUXSTAT);
806
807 if (value & DPAUX_DP_AUXSTAT_HPD_STATUS)
808 return connector_status_connected;
809
810 return connector_status_disconnected;
811 }
812
drm_dp_aux_enable(struct drm_dp_aux * aux)813 int drm_dp_aux_enable(struct drm_dp_aux *aux)
814 {
815 struct tegra_dpaux *dpaux = to_dpaux(aux);
816
817 return tegra_dpaux_pad_config(dpaux, DPAUX_PADCTL_FUNC_AUX);
818 }
819
drm_dp_aux_disable(struct drm_dp_aux * aux)820 int drm_dp_aux_disable(struct drm_dp_aux *aux)
821 {
822 struct tegra_dpaux *dpaux = to_dpaux(aux);
823
824 tegra_dpaux_pad_power_down(dpaux);
825
826 return 0;
827 }
828