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v5.4
  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/gpio.h>
  9#include <linux/interrupt.h>
 10#include <linux/io.h>
 11#include <linux/module.h>
 12#include <linux/of_gpio.h>
 13#include <linux/pinctrl/pinconf-generic.h>
 14#include <linux/pinctrl/pinctrl.h>
 15#include <linux/pinctrl/pinmux.h>
 16#include <linux/platform_device.h>
 17#include <linux/pm_runtime.h>
 18#include <linux/regulator/consumer.h>
 19#include <linux/reset.h>
 20#include <linux/workqueue.h>
 21
 22#include <drm/drm_dp_helper.h>
 23#include <drm/drm_panel.h>
 24
 
 25#include "dpaux.h"
 26#include "drm.h"
 27#include "trace.h"
 28
 29static DEFINE_MUTEX(dpaux_lock);
 30static LIST_HEAD(dpaux_list);
 31
 
 
 
 
 
 
 32struct tegra_dpaux {
 33	struct drm_dp_aux aux;
 34	struct device *dev;
 35
 
 
 36	void __iomem *regs;
 37	int irq;
 38
 39	struct tegra_output *output;
 40
 41	struct reset_control *rst;
 42	struct clk *clk_parent;
 43	struct clk *clk;
 44
 45	struct regulator *vdd;
 46
 47	struct completion complete;
 48	struct work_struct work;
 49	struct list_head list;
 50
 51#ifdef CONFIG_GENERIC_PINCONF
 52	struct pinctrl_dev *pinctrl;
 53	struct pinctrl_desc desc;
 54#endif
 55};
 56
 57static inline struct tegra_dpaux *to_dpaux(struct drm_dp_aux *aux)
 58{
 59	return container_of(aux, struct tegra_dpaux, aux);
 60}
 61
 62static inline struct tegra_dpaux *work_to_dpaux(struct work_struct *work)
 63{
 64	return container_of(work, struct tegra_dpaux, work);
 65}
 66
 67static inline u32 tegra_dpaux_readl(struct tegra_dpaux *dpaux,
 68				    unsigned int offset)
 69{
 70	u32 value = readl(dpaux->regs + (offset << 2));
 71
 72	trace_dpaux_readl(dpaux->dev, offset, value);
 73
 74	return value;
 75}
 76
 77static inline void tegra_dpaux_writel(struct tegra_dpaux *dpaux,
 78				      u32 value, unsigned int offset)
 79{
 80	trace_dpaux_writel(dpaux->dev, offset, value);
 81	writel(value, dpaux->regs + (offset << 2));
 82}
 83
 84static void tegra_dpaux_write_fifo(struct tegra_dpaux *dpaux, const u8 *buffer,
 85				   size_t size)
 86{
 87	size_t i, j;
 88
 89	for (i = 0; i < DIV_ROUND_UP(size, 4); i++) {
 90		size_t num = min_t(size_t, size - i * 4, 4);
 91		u32 value = 0;
 92
 93		for (j = 0; j < num; j++)
 94			value |= buffer[i * 4 + j] << (j * 8);
 95
 96		tegra_dpaux_writel(dpaux, value, DPAUX_DP_AUXDATA_WRITE(i));
 97	}
 98}
 99
100static void tegra_dpaux_read_fifo(struct tegra_dpaux *dpaux, u8 *buffer,
101				  size_t size)
102{
103	size_t i, j;
104
105	for (i = 0; i < DIV_ROUND_UP(size, 4); i++) {
106		size_t num = min_t(size_t, size - i * 4, 4);
107		u32 value;
108
109		value = tegra_dpaux_readl(dpaux, DPAUX_DP_AUXDATA_READ(i));
110
111		for (j = 0; j < num; j++)
112			buffer[i * 4 + j] = value >> (j * 8);
113	}
114}
115
116static ssize_t tegra_dpaux_transfer(struct drm_dp_aux *aux,
117				    struct drm_dp_aux_msg *msg)
118{
119	unsigned long timeout = msecs_to_jiffies(250);
120	struct tegra_dpaux *dpaux = to_dpaux(aux);
121	unsigned long status;
122	ssize_t ret = 0;
 
123	u32 value;
124
125	/* Tegra has 4x4 byte DP AUX transmit and receive FIFOs. */
126	if (msg->size > 16)
127		return -EINVAL;
128
129	/*
130	 * Allow zero-sized messages only for I2C, in which case they specify
131	 * address-only transactions.
132	 */
133	if (msg->size < 1) {
134		switch (msg->request & ~DP_AUX_I2C_MOT) {
135		case DP_AUX_I2C_WRITE_STATUS_UPDATE:
136		case DP_AUX_I2C_WRITE:
137		case DP_AUX_I2C_READ:
138			value = DPAUX_DP_AUXCTL_CMD_ADDRESS_ONLY;
139			break;
140
141		default:
142			return -EINVAL;
143		}
144	} else {
145		/* For non-zero-sized messages, set the CMDLEN field. */
146		value = DPAUX_DP_AUXCTL_CMDLEN(msg->size - 1);
147	}
148
149	switch (msg->request & ~DP_AUX_I2C_MOT) {
150	case DP_AUX_I2C_WRITE:
151		if (msg->request & DP_AUX_I2C_MOT)
152			value |= DPAUX_DP_AUXCTL_CMD_MOT_WR;
153		else
154			value |= DPAUX_DP_AUXCTL_CMD_I2C_WR;
155
156		break;
157
158	case DP_AUX_I2C_READ:
159		if (msg->request & DP_AUX_I2C_MOT)
160			value |= DPAUX_DP_AUXCTL_CMD_MOT_RD;
161		else
162			value |= DPAUX_DP_AUXCTL_CMD_I2C_RD;
163
164		break;
165
166	case DP_AUX_I2C_WRITE_STATUS_UPDATE:
167		if (msg->request & DP_AUX_I2C_MOT)
168			value |= DPAUX_DP_AUXCTL_CMD_MOT_RQ;
169		else
170			value |= DPAUX_DP_AUXCTL_CMD_I2C_RQ;
171
172		break;
173
174	case DP_AUX_NATIVE_WRITE:
175		value |= DPAUX_DP_AUXCTL_CMD_AUX_WR;
176		break;
177
178	case DP_AUX_NATIVE_READ:
179		value |= DPAUX_DP_AUXCTL_CMD_AUX_RD;
180		break;
181
182	default:
183		return -EINVAL;
184	}
185
186	tegra_dpaux_writel(dpaux, msg->address, DPAUX_DP_AUXADDR);
187	tegra_dpaux_writel(dpaux, value, DPAUX_DP_AUXCTL);
188
189	if ((msg->request & DP_AUX_I2C_READ) == 0) {
190		tegra_dpaux_write_fifo(dpaux, msg->buffer, msg->size);
191		ret = msg->size;
192	}
193
194	/* start transaction */
195	value = tegra_dpaux_readl(dpaux, DPAUX_DP_AUXCTL);
196	value |= DPAUX_DP_AUXCTL_TRANSACTREQ;
197	tegra_dpaux_writel(dpaux, value, DPAUX_DP_AUXCTL);
198
199	status = wait_for_completion_timeout(&dpaux->complete, timeout);
200	if (!status)
201		return -ETIMEDOUT;
202
203	/* read status and clear errors */
204	value = tegra_dpaux_readl(dpaux, DPAUX_DP_AUXSTAT);
205	tegra_dpaux_writel(dpaux, 0xf00, DPAUX_DP_AUXSTAT);
206
207	if (value & DPAUX_DP_AUXSTAT_TIMEOUT_ERROR)
208		return -ETIMEDOUT;
209
210	if ((value & DPAUX_DP_AUXSTAT_RX_ERROR) ||
211	    (value & DPAUX_DP_AUXSTAT_SINKSTAT_ERROR) ||
212	    (value & DPAUX_DP_AUXSTAT_NO_STOP_ERROR))
213		return -EIO;
214
215	switch ((value & DPAUX_DP_AUXSTAT_REPLY_TYPE_MASK) >> 16) {
216	case 0x00:
217		msg->reply = DP_AUX_NATIVE_REPLY_ACK;
218		break;
219
220	case 0x01:
221		msg->reply = DP_AUX_NATIVE_REPLY_NACK;
222		break;
223
224	case 0x02:
225		msg->reply = DP_AUX_NATIVE_REPLY_DEFER;
226		break;
227
228	case 0x04:
229		msg->reply = DP_AUX_I2C_REPLY_NACK;
230		break;
231
232	case 0x08:
233		msg->reply = DP_AUX_I2C_REPLY_DEFER;
234		break;
235	}
236
237	if ((msg->size > 0) && (msg->reply == DP_AUX_NATIVE_REPLY_ACK)) {
238		if (msg->request & DP_AUX_I2C_READ) {
239			size_t count = value & DPAUX_DP_AUXSTAT_REPLY_MASK;
240
241			if (WARN_ON(count != msg->size))
242				count = min_t(size_t, count, msg->size);
 
 
 
 
 
 
 
243
244			tegra_dpaux_read_fifo(dpaux, msg->buffer, count);
245			ret = count;
246		}
247	}
248
 
 
 
249	return ret;
250}
251
252static void tegra_dpaux_hotplug(struct work_struct *work)
253{
254	struct tegra_dpaux *dpaux = work_to_dpaux(work);
255
256	if (dpaux->output)
257		drm_helper_hpd_irq_event(dpaux->output->connector.dev);
258}
259
260static irqreturn_t tegra_dpaux_irq(int irq, void *data)
261{
262	struct tegra_dpaux *dpaux = data;
263	irqreturn_t ret = IRQ_HANDLED;
264	u32 value;
265
266	/* clear interrupts */
267	value = tegra_dpaux_readl(dpaux, DPAUX_INTR_AUX);
268	tegra_dpaux_writel(dpaux, value, DPAUX_INTR_AUX);
269
270	if (value & (DPAUX_INTR_PLUG_EVENT | DPAUX_INTR_UNPLUG_EVENT))
271		schedule_work(&dpaux->work);
272
273	if (value & DPAUX_INTR_IRQ_EVENT) {
274		/* TODO: handle this */
275	}
276
277	if (value & DPAUX_INTR_AUX_DONE)
278		complete(&dpaux->complete);
279
280	return ret;
281}
282
283enum tegra_dpaux_functions {
284	DPAUX_PADCTL_FUNC_AUX,
285	DPAUX_PADCTL_FUNC_I2C,
286	DPAUX_PADCTL_FUNC_OFF,
287};
288
289static void tegra_dpaux_pad_power_down(struct tegra_dpaux *dpaux)
290{
291	u32 value = tegra_dpaux_readl(dpaux, DPAUX_HYBRID_SPARE);
292
293	value |= DPAUX_HYBRID_SPARE_PAD_POWER_DOWN;
294
295	tegra_dpaux_writel(dpaux, value, DPAUX_HYBRID_SPARE);
296}
297
298static void tegra_dpaux_pad_power_up(struct tegra_dpaux *dpaux)
299{
300	u32 value = tegra_dpaux_readl(dpaux, DPAUX_HYBRID_SPARE);
301
302	value &= ~DPAUX_HYBRID_SPARE_PAD_POWER_DOWN;
303
304	tegra_dpaux_writel(dpaux, value, DPAUX_HYBRID_SPARE);
305}
306
307static int tegra_dpaux_pad_config(struct tegra_dpaux *dpaux, unsigned function)
308{
309	u32 value;
310
311	switch (function) {
312	case DPAUX_PADCTL_FUNC_AUX:
313		value = DPAUX_HYBRID_PADCTL_AUX_CMH(2) |
314			DPAUX_HYBRID_PADCTL_AUX_DRVZ(4) |
315			DPAUX_HYBRID_PADCTL_AUX_DRVI(0x18) |
316			DPAUX_HYBRID_PADCTL_AUX_INPUT_RCV |
317			DPAUX_HYBRID_PADCTL_MODE_AUX;
318		break;
319
320	case DPAUX_PADCTL_FUNC_I2C:
321		value = DPAUX_HYBRID_PADCTL_I2C_SDA_INPUT_RCV |
322			DPAUX_HYBRID_PADCTL_I2C_SCL_INPUT_RCV |
323			DPAUX_HYBRID_PADCTL_AUX_CMH(2) |
324			DPAUX_HYBRID_PADCTL_AUX_DRVZ(4) |
325			DPAUX_HYBRID_PADCTL_AUX_DRVI(0x18) |
326			DPAUX_HYBRID_PADCTL_MODE_I2C;
327		break;
328
329	case DPAUX_PADCTL_FUNC_OFF:
330		tegra_dpaux_pad_power_down(dpaux);
331		return 0;
332
333	default:
334		return -ENOTSUPP;
335	}
336
337	tegra_dpaux_writel(dpaux, value, DPAUX_HYBRID_PADCTL);
338	tegra_dpaux_pad_power_up(dpaux);
339
340	return 0;
341}
342
343#ifdef CONFIG_GENERIC_PINCONF
344static const struct pinctrl_pin_desc tegra_dpaux_pins[] = {
345	PINCTRL_PIN(0, "DP_AUX_CHx_P"),
346	PINCTRL_PIN(1, "DP_AUX_CHx_N"),
347};
348
349static const unsigned tegra_dpaux_pin_numbers[] = { 0, 1 };
350
351static const char * const tegra_dpaux_groups[] = {
352	"dpaux-io",
353};
354
355static const char * const tegra_dpaux_functions[] = {
356	"aux",
357	"i2c",
358	"off",
359};
360
361static int tegra_dpaux_get_groups_count(struct pinctrl_dev *pinctrl)
362{
363	return ARRAY_SIZE(tegra_dpaux_groups);
364}
365
366static const char *tegra_dpaux_get_group_name(struct pinctrl_dev *pinctrl,
367					      unsigned int group)
368{
369	return tegra_dpaux_groups[group];
370}
371
372static int tegra_dpaux_get_group_pins(struct pinctrl_dev *pinctrl,
373				      unsigned group, const unsigned **pins,
374				      unsigned *num_pins)
375{
376	*pins = tegra_dpaux_pin_numbers;
377	*num_pins = ARRAY_SIZE(tegra_dpaux_pin_numbers);
378
379	return 0;
380}
381
382static const struct pinctrl_ops tegra_dpaux_pinctrl_ops = {
383	.get_groups_count = tegra_dpaux_get_groups_count,
384	.get_group_name = tegra_dpaux_get_group_name,
385	.get_group_pins = tegra_dpaux_get_group_pins,
386	.dt_node_to_map = pinconf_generic_dt_node_to_map_group,
387	.dt_free_map = pinconf_generic_dt_free_map,
388};
389
390static int tegra_dpaux_get_functions_count(struct pinctrl_dev *pinctrl)
391{
392	return ARRAY_SIZE(tegra_dpaux_functions);
393}
394
395static const char *tegra_dpaux_get_function_name(struct pinctrl_dev *pinctrl,
396						 unsigned int function)
397{
398	return tegra_dpaux_functions[function];
399}
400
401static int tegra_dpaux_get_function_groups(struct pinctrl_dev *pinctrl,
402					   unsigned int function,
403					   const char * const **groups,
404					   unsigned * const num_groups)
405{
406	*num_groups = ARRAY_SIZE(tegra_dpaux_groups);
407	*groups = tegra_dpaux_groups;
408
409	return 0;
410}
411
412static int tegra_dpaux_set_mux(struct pinctrl_dev *pinctrl,
413			       unsigned int function, unsigned int group)
414{
415	struct tegra_dpaux *dpaux = pinctrl_dev_get_drvdata(pinctrl);
416
417	return tegra_dpaux_pad_config(dpaux, function);
418}
419
420static const struct pinmux_ops tegra_dpaux_pinmux_ops = {
421	.get_functions_count = tegra_dpaux_get_functions_count,
422	.get_function_name = tegra_dpaux_get_function_name,
423	.get_function_groups = tegra_dpaux_get_function_groups,
424	.set_mux = tegra_dpaux_set_mux,
425};
426#endif
427
428static int tegra_dpaux_probe(struct platform_device *pdev)
429{
430	struct tegra_dpaux *dpaux;
431	struct resource *regs;
432	u32 value;
433	int err;
434
435	dpaux = devm_kzalloc(&pdev->dev, sizeof(*dpaux), GFP_KERNEL);
436	if (!dpaux)
437		return -ENOMEM;
438
 
439	INIT_WORK(&dpaux->work, tegra_dpaux_hotplug);
440	init_completion(&dpaux->complete);
441	INIT_LIST_HEAD(&dpaux->list);
442	dpaux->dev = &pdev->dev;
443
444	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
445	dpaux->regs = devm_ioremap_resource(&pdev->dev, regs);
446	if (IS_ERR(dpaux->regs))
447		return PTR_ERR(dpaux->regs);
448
449	dpaux->irq = platform_get_irq(pdev, 0);
450	if (dpaux->irq < 0) {
451		dev_err(&pdev->dev, "failed to get IRQ\n");
452		return -ENXIO;
453	}
454
455	if (!pdev->dev.pm_domain) {
456		dpaux->rst = devm_reset_control_get(&pdev->dev, "dpaux");
457		if (IS_ERR(dpaux->rst)) {
458			dev_err(&pdev->dev,
459				"failed to get reset control: %ld\n",
460				PTR_ERR(dpaux->rst));
461			return PTR_ERR(dpaux->rst);
462		}
463	}
464
465	dpaux->clk = devm_clk_get(&pdev->dev, NULL);
466	if (IS_ERR(dpaux->clk)) {
467		dev_err(&pdev->dev, "failed to get module clock: %ld\n",
468			PTR_ERR(dpaux->clk));
469		return PTR_ERR(dpaux->clk);
470	}
471
472	dpaux->clk_parent = devm_clk_get(&pdev->dev, "parent");
473	if (IS_ERR(dpaux->clk_parent)) {
474		dev_err(&pdev->dev, "failed to get parent clock: %ld\n",
475			PTR_ERR(dpaux->clk_parent));
476		return PTR_ERR(dpaux->clk_parent);
477	}
478
479	err = clk_set_rate(dpaux->clk_parent, 270000000);
480	if (err < 0) {
481		dev_err(&pdev->dev, "failed to set clock to 270 MHz: %d\n",
482			err);
483		return err;
484	}
485
486	dpaux->vdd = devm_regulator_get_optional(&pdev->dev, "vdd");
487	if (IS_ERR(dpaux->vdd)) {
488		if (PTR_ERR(dpaux->vdd) != -ENODEV) {
489			if (PTR_ERR(dpaux->vdd) != -EPROBE_DEFER)
490				dev_err(&pdev->dev,
491					"failed to get VDD supply: %ld\n",
492					PTR_ERR(dpaux->vdd));
493
494			return PTR_ERR(dpaux->vdd);
495		}
 
 
496	}
497
498	platform_set_drvdata(pdev, dpaux);
499	pm_runtime_enable(&pdev->dev);
500	pm_runtime_get_sync(&pdev->dev);
501
502	err = devm_request_irq(dpaux->dev, dpaux->irq, tegra_dpaux_irq, 0,
503			       dev_name(dpaux->dev), dpaux);
504	if (err < 0) {
505		dev_err(dpaux->dev, "failed to request IRQ#%u: %d\n",
506			dpaux->irq, err);
507		return err;
508	}
509
510	disable_irq(dpaux->irq);
511
512	dpaux->aux.transfer = tegra_dpaux_transfer;
513	dpaux->aux.dev = &pdev->dev;
514
515	err = drm_dp_aux_register(&dpaux->aux);
516	if (err < 0)
517		return err;
518
519	/*
520	 * Assume that by default the DPAUX/I2C pads will be used for HDMI,
521	 * so power them up and configure them in I2C mode.
522	 *
523	 * The DPAUX code paths reconfigure the pads in AUX mode, but there
524	 * is no possibility to perform the I2C mode configuration in the
525	 * HDMI path.
526	 */
527	err = tegra_dpaux_pad_config(dpaux, DPAUX_PADCTL_FUNC_I2C);
528	if (err < 0)
529		return err;
530
531#ifdef CONFIG_GENERIC_PINCONF
532	dpaux->desc.name = dev_name(&pdev->dev);
533	dpaux->desc.pins = tegra_dpaux_pins;
534	dpaux->desc.npins = ARRAY_SIZE(tegra_dpaux_pins);
535	dpaux->desc.pctlops = &tegra_dpaux_pinctrl_ops;
536	dpaux->desc.pmxops = &tegra_dpaux_pinmux_ops;
537	dpaux->desc.owner = THIS_MODULE;
538
539	dpaux->pinctrl = devm_pinctrl_register(&pdev->dev, &dpaux->desc, dpaux);
540	if (IS_ERR(dpaux->pinctrl)) {
541		dev_err(&pdev->dev, "failed to register pincontrol\n");
542		return PTR_ERR(dpaux->pinctrl);
543	}
544#endif
545	/* enable and clear all interrupts */
546	value = DPAUX_INTR_AUX_DONE | DPAUX_INTR_IRQ_EVENT |
547		DPAUX_INTR_UNPLUG_EVENT | DPAUX_INTR_PLUG_EVENT;
548	tegra_dpaux_writel(dpaux, value, DPAUX_INTR_EN_AUX);
549	tegra_dpaux_writel(dpaux, value, DPAUX_INTR_AUX);
550
551	mutex_lock(&dpaux_lock);
552	list_add_tail(&dpaux->list, &dpaux_list);
553	mutex_unlock(&dpaux_lock);
554
555	return 0;
556}
557
558static int tegra_dpaux_remove(struct platform_device *pdev)
559{
560	struct tegra_dpaux *dpaux = platform_get_drvdata(pdev);
561
562	cancel_work_sync(&dpaux->work);
563
564	/* make sure pads are powered down when not in use */
565	tegra_dpaux_pad_power_down(dpaux);
566
567	pm_runtime_put(&pdev->dev);
568	pm_runtime_disable(&pdev->dev);
569
570	drm_dp_aux_unregister(&dpaux->aux);
571
572	mutex_lock(&dpaux_lock);
573	list_del(&dpaux->list);
574	mutex_unlock(&dpaux_lock);
575
576	return 0;
577}
578
579#ifdef CONFIG_PM
580static int tegra_dpaux_suspend(struct device *dev)
581{
582	struct tegra_dpaux *dpaux = dev_get_drvdata(dev);
583	int err = 0;
584
585	if (dpaux->rst) {
586		err = reset_control_assert(dpaux->rst);
587		if (err < 0) {
588			dev_err(dev, "failed to assert reset: %d\n", err);
589			return err;
590		}
591	}
592
593	usleep_range(1000, 2000);
594
595	clk_disable_unprepare(dpaux->clk_parent);
596	clk_disable_unprepare(dpaux->clk);
597
598	return err;
599}
600
601static int tegra_dpaux_resume(struct device *dev)
602{
603	struct tegra_dpaux *dpaux = dev_get_drvdata(dev);
604	int err;
605
606	err = clk_prepare_enable(dpaux->clk);
607	if (err < 0) {
608		dev_err(dev, "failed to enable clock: %d\n", err);
609		return err;
610	}
611
612	err = clk_prepare_enable(dpaux->clk_parent);
613	if (err < 0) {
614		dev_err(dev, "failed to enable parent clock: %d\n", err);
615		goto disable_clk;
616	}
617
618	usleep_range(1000, 2000);
619
620	if (dpaux->rst) {
621		err = reset_control_deassert(dpaux->rst);
622		if (err < 0) {
623			dev_err(dev, "failed to deassert reset: %d\n", err);
624			goto disable_parent;
625		}
626
627		usleep_range(1000, 2000);
628	}
629
630	return 0;
631
632disable_parent:
633	clk_disable_unprepare(dpaux->clk_parent);
634disable_clk:
635	clk_disable_unprepare(dpaux->clk);
636	return err;
637}
638#endif
639
640static const struct dev_pm_ops tegra_dpaux_pm_ops = {
641	SET_RUNTIME_PM_OPS(tegra_dpaux_suspend, tegra_dpaux_resume, NULL)
642};
643
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
644static const struct of_device_id tegra_dpaux_of_match[] = {
645	{ .compatible = "nvidia,tegra194-dpaux", },
646	{ .compatible = "nvidia,tegra186-dpaux", },
647	{ .compatible = "nvidia,tegra210-dpaux", },
648	{ .compatible = "nvidia,tegra124-dpaux", },
649	{ },
650};
651MODULE_DEVICE_TABLE(of, tegra_dpaux_of_match);
652
653struct platform_driver tegra_dpaux_driver = {
654	.driver = {
655		.name = "tegra-dpaux",
656		.of_match_table = tegra_dpaux_of_match,
657		.pm = &tegra_dpaux_pm_ops,
658	},
659	.probe = tegra_dpaux_probe,
660	.remove = tegra_dpaux_remove,
661};
662
663struct drm_dp_aux *drm_dp_aux_find_by_of_node(struct device_node *np)
664{
665	struct tegra_dpaux *dpaux;
666
667	mutex_lock(&dpaux_lock);
668
669	list_for_each_entry(dpaux, &dpaux_list, list)
670		if (np == dpaux->dev->of_node) {
671			mutex_unlock(&dpaux_lock);
672			return &dpaux->aux;
673		}
674
675	mutex_unlock(&dpaux_lock);
676
677	return NULL;
678}
679
680int drm_dp_aux_attach(struct drm_dp_aux *aux, struct tegra_output *output)
681{
682	struct tegra_dpaux *dpaux = to_dpaux(aux);
683	unsigned long timeout;
684	int err;
685
686	output->connector.polled = DRM_CONNECTOR_POLL_HPD;
687	dpaux->output = output;
688
689	err = regulator_enable(dpaux->vdd);
690	if (err < 0)
691		return err;
692
693	timeout = jiffies + msecs_to_jiffies(250);
 
694
695	while (time_before(jiffies, timeout)) {
696		enum drm_connector_status status;
697
698		status = drm_dp_aux_detect(aux);
699		if (status == connector_status_connected) {
700			enable_irq(dpaux->irq);
701			return 0;
702		}
703
704		usleep_range(1000, 2000);
 
 
 
 
 
 
 
 
 
 
 
 
705	}
706
707	return -ETIMEDOUT;
 
708}
709
710int drm_dp_aux_detach(struct drm_dp_aux *aux)
711{
712	struct tegra_dpaux *dpaux = to_dpaux(aux);
713	unsigned long timeout;
714	int err;
715
 
716	disable_irq(dpaux->irq);
717
718	err = regulator_disable(dpaux->vdd);
719	if (err < 0)
720		return err;
721
722	timeout = jiffies + msecs_to_jiffies(250);
 
 
 
 
723
724	while (time_before(jiffies, timeout)) {
725		enum drm_connector_status status;
 
 
726
727		status = drm_dp_aux_detect(aux);
728		if (status == connector_status_disconnected) {
729			dpaux->output = NULL;
730			return 0;
731		}
732
733		usleep_range(1000, 2000);
 
 
 
734	}
735
736	return -ETIMEDOUT;
737}
738
739enum drm_connector_status drm_dp_aux_detect(struct drm_dp_aux *aux)
740{
741	struct tegra_dpaux *dpaux = to_dpaux(aux);
742	u32 value;
743
744	value = tegra_dpaux_readl(dpaux, DPAUX_DP_AUXSTAT);
745
746	if (value & DPAUX_DP_AUXSTAT_HPD_STATUS)
747		return connector_status_connected;
748
749	return connector_status_disconnected;
750}
751
752int drm_dp_aux_enable(struct drm_dp_aux *aux)
753{
754	struct tegra_dpaux *dpaux = to_dpaux(aux);
755
756	return tegra_dpaux_pad_config(dpaux, DPAUX_PADCTL_FUNC_AUX);
757}
758
759int drm_dp_aux_disable(struct drm_dp_aux *aux)
760{
761	struct tegra_dpaux *dpaux = to_dpaux(aux);
762
763	tegra_dpaux_pad_power_down(dpaux);
764
765	return 0;
766}
767
768int drm_dp_aux_prepare(struct drm_dp_aux *aux, u8 encoding)
769{
770	int err;
771
772	err = drm_dp_dpcd_writeb(aux, DP_MAIN_LINK_CHANNEL_CODING_SET,
773				 encoding);
774	if (err < 0)
775		return err;
776
777	return 0;
778}
779
780int drm_dp_aux_train(struct drm_dp_aux *aux, struct drm_dp_link *link,
781		     u8 pattern)
782{
783	u8 tp = pattern & DP_TRAINING_PATTERN_MASK;
784	u8 status[DP_LINK_STATUS_SIZE], values[4];
785	unsigned int i;
786	int err;
787
788	err = drm_dp_dpcd_writeb(aux, DP_TRAINING_PATTERN_SET, pattern);
789	if (err < 0)
790		return err;
791
792	if (tp == DP_TRAINING_PATTERN_DISABLE)
793		return 0;
794
795	for (i = 0; i < link->num_lanes; i++)
796		values[i] = DP_TRAIN_MAX_PRE_EMPHASIS_REACHED |
797			    DP_TRAIN_PRE_EMPH_LEVEL_0 |
798			    DP_TRAIN_MAX_SWING_REACHED |
799			    DP_TRAIN_VOLTAGE_SWING_LEVEL_0;
800
801	err = drm_dp_dpcd_write(aux, DP_TRAINING_LANE0_SET, values,
802				link->num_lanes);
803	if (err < 0)
804		return err;
805
806	usleep_range(500, 1000);
807
808	err = drm_dp_dpcd_read_link_status(aux, status);
809	if (err < 0)
810		return err;
811
812	switch (tp) {
813	case DP_TRAINING_PATTERN_1:
814		if (!drm_dp_clock_recovery_ok(status, link->num_lanes))
815			return -EAGAIN;
816
817		break;
818
819	case DP_TRAINING_PATTERN_2:
820		if (!drm_dp_channel_eq_ok(status, link->num_lanes))
821			return -EAGAIN;
822
823		break;
824
825	default:
826		dev_err(aux->dev, "unsupported training pattern %u\n", tp);
827		return -EINVAL;
828	}
829
830	err = drm_dp_dpcd_writeb(aux, DP_EDP_CONFIGURATION_SET, 0);
831	if (err < 0)
832		return err;
833
834	return 0;
835}
v5.14.15
  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_device.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/drm_dp_helper.h>
 22#include <drm/drm_panel.h>
 23
 24#include "dp.h"
 25#include "dpaux.h"
 26#include "drm.h"
 27#include "trace.h"
 28
 29static DEFINE_MUTEX(dpaux_lock);
 30static LIST_HEAD(dpaux_list);
 31
 32struct tegra_dpaux_soc {
 33	unsigned int cmh;
 34	unsigned int drvz;
 35	unsigned int drvi;
 36};
 37
 38struct tegra_dpaux {
 39	struct drm_dp_aux aux;
 40	struct device *dev;
 41
 42	const struct tegra_dpaux_soc *soc;
 43
 44	void __iomem *regs;
 45	int irq;
 46
 47	struct tegra_output *output;
 48
 49	struct reset_control *rst;
 50	struct clk *clk_parent;
 51	struct clk *clk;
 52
 53	struct regulator *vdd;
 54
 55	struct completion complete;
 56	struct work_struct work;
 57	struct list_head list;
 58
 59#ifdef CONFIG_GENERIC_PINCONF
 60	struct pinctrl_dev *pinctrl;
 61	struct pinctrl_desc desc;
 62#endif
 63};
 64
 65static inline struct tegra_dpaux *to_dpaux(struct drm_dp_aux *aux)
 66{
 67	return container_of(aux, struct tegra_dpaux, aux);
 68}
 69
 70static inline struct tegra_dpaux *work_to_dpaux(struct work_struct *work)
 71{
 72	return container_of(work, struct tegra_dpaux, work);
 73}
 74
 75static inline u32 tegra_dpaux_readl(struct tegra_dpaux *dpaux,
 76				    unsigned int offset)
 77{
 78	u32 value = readl(dpaux->regs + (offset << 2));
 79
 80	trace_dpaux_readl(dpaux->dev, offset, value);
 81
 82	return value;
 83}
 84
 85static inline void tegra_dpaux_writel(struct tegra_dpaux *dpaux,
 86				      u32 value, unsigned int offset)
 87{
 88	trace_dpaux_writel(dpaux->dev, offset, value);
 89	writel(value, dpaux->regs + (offset << 2));
 90}
 91
 92static void tegra_dpaux_write_fifo(struct tegra_dpaux *dpaux, const u8 *buffer,
 93				   size_t size)
 94{
 95	size_t i, j;
 96
 97	for (i = 0; i < DIV_ROUND_UP(size, 4); i++) {
 98		size_t num = min_t(size_t, size - i * 4, 4);
 99		u32 value = 0;
100
101		for (j = 0; j < num; j++)
102			value |= buffer[i * 4 + j] << (j * 8);
103
104		tegra_dpaux_writel(dpaux, value, DPAUX_DP_AUXDATA_WRITE(i));
105	}
106}
107
108static void tegra_dpaux_read_fifo(struct tegra_dpaux *dpaux, u8 *buffer,
109				  size_t size)
110{
111	size_t i, j;
112
113	for (i = 0; i < DIV_ROUND_UP(size, 4); i++) {
114		size_t num = min_t(size_t, size - i * 4, 4);
115		u32 value;
116
117		value = tegra_dpaux_readl(dpaux, DPAUX_DP_AUXDATA_READ(i));
118
119		for (j = 0; j < num; j++)
120			buffer[i * 4 + j] = value >> (j * 8);
121	}
122}
123
124static ssize_t tegra_dpaux_transfer(struct drm_dp_aux *aux,
125				    struct drm_dp_aux_msg *msg)
126{
127	unsigned long timeout = msecs_to_jiffies(250);
128	struct tegra_dpaux *dpaux = to_dpaux(aux);
129	unsigned long status;
130	ssize_t ret = 0;
131	u8 reply = 0;
132	u32 value;
133
134	/* Tegra has 4x4 byte DP AUX transmit and receive FIFOs. */
135	if (msg->size > 16)
136		return -EINVAL;
137
138	/*
139	 * Allow zero-sized messages only for I2C, in which case they specify
140	 * address-only transactions.
141	 */
142	if (msg->size < 1) {
143		switch (msg->request & ~DP_AUX_I2C_MOT) {
144		case DP_AUX_I2C_WRITE_STATUS_UPDATE:
145		case DP_AUX_I2C_WRITE:
146		case DP_AUX_I2C_READ:
147			value = DPAUX_DP_AUXCTL_CMD_ADDRESS_ONLY;
148			break;
149
150		default:
151			return -EINVAL;
152		}
153	} else {
154		/* For non-zero-sized messages, set the CMDLEN field. */
155		value = DPAUX_DP_AUXCTL_CMDLEN(msg->size - 1);
156	}
157
158	switch (msg->request & ~DP_AUX_I2C_MOT) {
159	case DP_AUX_I2C_WRITE:
160		if (msg->request & DP_AUX_I2C_MOT)
161			value |= DPAUX_DP_AUXCTL_CMD_MOT_WR;
162		else
163			value |= DPAUX_DP_AUXCTL_CMD_I2C_WR;
164
165		break;
166
167	case DP_AUX_I2C_READ:
168		if (msg->request & DP_AUX_I2C_MOT)
169			value |= DPAUX_DP_AUXCTL_CMD_MOT_RD;
170		else
171			value |= DPAUX_DP_AUXCTL_CMD_I2C_RD;
172
173		break;
174
175	case DP_AUX_I2C_WRITE_STATUS_UPDATE:
176		if (msg->request & DP_AUX_I2C_MOT)
177			value |= DPAUX_DP_AUXCTL_CMD_MOT_RQ;
178		else
179			value |= DPAUX_DP_AUXCTL_CMD_I2C_RQ;
180
181		break;
182
183	case DP_AUX_NATIVE_WRITE:
184		value |= DPAUX_DP_AUXCTL_CMD_AUX_WR;
185		break;
186
187	case DP_AUX_NATIVE_READ:
188		value |= DPAUX_DP_AUXCTL_CMD_AUX_RD;
189		break;
190
191	default:
192		return -EINVAL;
193	}
194
195	tegra_dpaux_writel(dpaux, msg->address, DPAUX_DP_AUXADDR);
196	tegra_dpaux_writel(dpaux, value, DPAUX_DP_AUXCTL);
197
198	if ((msg->request & DP_AUX_I2C_READ) == 0) {
199		tegra_dpaux_write_fifo(dpaux, msg->buffer, msg->size);
200		ret = msg->size;
201	}
202
203	/* start transaction */
204	value = tegra_dpaux_readl(dpaux, DPAUX_DP_AUXCTL);
205	value |= DPAUX_DP_AUXCTL_TRANSACTREQ;
206	tegra_dpaux_writel(dpaux, value, DPAUX_DP_AUXCTL);
207
208	status = wait_for_completion_timeout(&dpaux->complete, timeout);
209	if (!status)
210		return -ETIMEDOUT;
211
212	/* read status and clear errors */
213	value = tegra_dpaux_readl(dpaux, DPAUX_DP_AUXSTAT);
214	tegra_dpaux_writel(dpaux, 0xf00, DPAUX_DP_AUXSTAT);
215
216	if (value & DPAUX_DP_AUXSTAT_TIMEOUT_ERROR)
217		return -ETIMEDOUT;
218
219	if ((value & DPAUX_DP_AUXSTAT_RX_ERROR) ||
220	    (value & DPAUX_DP_AUXSTAT_SINKSTAT_ERROR) ||
221	    (value & DPAUX_DP_AUXSTAT_NO_STOP_ERROR))
222		return -EIO;
223
224	switch ((value & DPAUX_DP_AUXSTAT_REPLY_TYPE_MASK) >> 16) {
225	case 0x00:
226		reply = DP_AUX_NATIVE_REPLY_ACK;
227		break;
228
229	case 0x01:
230		reply = DP_AUX_NATIVE_REPLY_NACK;
231		break;
232
233	case 0x02:
234		reply = DP_AUX_NATIVE_REPLY_DEFER;
235		break;
236
237	case 0x04:
238		reply = DP_AUX_I2C_REPLY_NACK;
239		break;
240
241	case 0x08:
242		reply = DP_AUX_I2C_REPLY_DEFER;
243		break;
244	}
245
246	if ((msg->size > 0) && (msg->reply == DP_AUX_NATIVE_REPLY_ACK)) {
247		if (msg->request & DP_AUX_I2C_READ) {
248			size_t count = value & DPAUX_DP_AUXSTAT_REPLY_MASK;
249
250			/*
251			 * There might be a smarter way to do this, but since
252			 * the DP helpers will already retry transactions for
253			 * an -EBUSY return value, simply reuse that instead.
254			 */
255			if (count != msg->size) {
256				ret = -EBUSY;
257				goto out;
258			}
259
260			tegra_dpaux_read_fifo(dpaux, msg->buffer, count);
261			ret = count;
262		}
263	}
264
265	msg->reply = reply;
266
267out:
268	return ret;
269}
270
271static void tegra_dpaux_hotplug(struct work_struct *work)
272{
273	struct tegra_dpaux *dpaux = work_to_dpaux(work);
274
275	if (dpaux->output)
276		drm_helper_hpd_irq_event(dpaux->output->connector.dev);
277}
278
279static irqreturn_t tegra_dpaux_irq(int irq, void *data)
280{
281	struct tegra_dpaux *dpaux = data;
282	irqreturn_t ret = IRQ_HANDLED;
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 ret;
300}
301
302enum tegra_dpaux_functions {
303	DPAUX_PADCTL_FUNC_AUX,
304	DPAUX_PADCTL_FUNC_I2C,
305	DPAUX_PADCTL_FUNC_OFF,
306};
307
308static 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
317static 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
326static 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
363static 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
368static const unsigned tegra_dpaux_pin_numbers[] = { 0, 1 };
369
370static const char * const tegra_dpaux_groups[] = {
371	"dpaux-io",
372};
373
374static const char * const tegra_dpaux_functions[] = {
375	"aux",
376	"i2c",
377	"off",
378};
379
380static int tegra_dpaux_get_groups_count(struct pinctrl_dev *pinctrl)
381{
382	return ARRAY_SIZE(tegra_dpaux_groups);
383}
384
385static const char *tegra_dpaux_get_group_name(struct pinctrl_dev *pinctrl,
386					      unsigned int group)
387{
388	return tegra_dpaux_groups[group];
389}
390
391static 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
401static 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
409static int tegra_dpaux_get_functions_count(struct pinctrl_dev *pinctrl)
410{
411	return ARRAY_SIZE(tegra_dpaux_functions);
412}
413
414static const char *tegra_dpaux_get_function_name(struct pinctrl_dev *pinctrl,
415						 unsigned int function)
416{
417	return tegra_dpaux_functions[function];
418}
419
420static 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
431static 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
439static 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
447static int tegra_dpaux_probe(struct platform_device *pdev)
448{
449	struct tegra_dpaux *dpaux;
450	struct resource *regs;
451	u32 value;
452	int err;
453
454	dpaux = devm_kzalloc(&pdev->dev, sizeof(*dpaux), GFP_KERNEL);
455	if (!dpaux)
456		return -ENOMEM;
457
458	dpaux->soc = of_device_get_match_data(&pdev->dev);
459	INIT_WORK(&dpaux->work, tegra_dpaux_hotplug);
460	init_completion(&dpaux->complete);
461	INIT_LIST_HEAD(&dpaux->list);
462	dpaux->dev = &pdev->dev;
463
464	regs = platform_get_resource(pdev, IORESOURCE_MEM, 0);
465	dpaux->regs = devm_ioremap_resource(&pdev->dev, regs);
466	if (IS_ERR(dpaux->regs))
467		return PTR_ERR(dpaux->regs);
468
469	dpaux->irq = platform_get_irq(pdev, 0);
470	if (dpaux->irq < 0)
 
471		return -ENXIO;
 
472
473	if (!pdev->dev.pm_domain) {
474		dpaux->rst = devm_reset_control_get(&pdev->dev, "dpaux");
475		if (IS_ERR(dpaux->rst)) {
476			dev_err(&pdev->dev,
477				"failed to get reset control: %ld\n",
478				PTR_ERR(dpaux->rst));
479			return PTR_ERR(dpaux->rst);
480		}
481	}
482
483	dpaux->clk = devm_clk_get(&pdev->dev, NULL);
484	if (IS_ERR(dpaux->clk)) {
485		dev_err(&pdev->dev, "failed to get module clock: %ld\n",
486			PTR_ERR(dpaux->clk));
487		return PTR_ERR(dpaux->clk);
488	}
489
490	dpaux->clk_parent = devm_clk_get(&pdev->dev, "parent");
491	if (IS_ERR(dpaux->clk_parent)) {
492		dev_err(&pdev->dev, "failed to get parent clock: %ld\n",
493			PTR_ERR(dpaux->clk_parent));
494		return PTR_ERR(dpaux->clk_parent);
495	}
496
497	err = clk_set_rate(dpaux->clk_parent, 270000000);
498	if (err < 0) {
499		dev_err(&pdev->dev, "failed to set clock to 270 MHz: %d\n",
500			err);
501		return err;
502	}
503
504	dpaux->vdd = devm_regulator_get_optional(&pdev->dev, "vdd");
505	if (IS_ERR(dpaux->vdd)) {
506		if (PTR_ERR(dpaux->vdd) != -ENODEV) {
507			if (PTR_ERR(dpaux->vdd) != -EPROBE_DEFER)
508				dev_err(&pdev->dev,
509					"failed to get VDD supply: %ld\n",
510					PTR_ERR(dpaux->vdd));
511
512			return PTR_ERR(dpaux->vdd);
513		}
514
515		dpaux->vdd = NULL;
516	}
517
518	platform_set_drvdata(pdev, dpaux);
519	pm_runtime_enable(&pdev->dev);
520	pm_runtime_get_sync(&pdev->dev);
521
522	err = devm_request_irq(dpaux->dev, dpaux->irq, tegra_dpaux_irq, 0,
523			       dev_name(dpaux->dev), dpaux);
524	if (err < 0) {
525		dev_err(dpaux->dev, "failed to request IRQ#%u: %d\n",
526			dpaux->irq, err);
527		return err;
528	}
529
530	disable_irq(dpaux->irq);
531
532	dpaux->aux.transfer = tegra_dpaux_transfer;
533	dpaux->aux.dev = &pdev->dev;
534
535	drm_dp_aux_init(&dpaux->aux);
 
 
536
537	/*
538	 * Assume that by default the DPAUX/I2C pads will be used for HDMI,
539	 * so power them up and configure them in I2C mode.
540	 *
541	 * The DPAUX code paths reconfigure the pads in AUX mode, but there
542	 * is no possibility to perform the I2C mode configuration in the
543	 * HDMI path.
544	 */
545	err = tegra_dpaux_pad_config(dpaux, DPAUX_PADCTL_FUNC_I2C);
546	if (err < 0)
547		return err;
548
549#ifdef CONFIG_GENERIC_PINCONF
550	dpaux->desc.name = dev_name(&pdev->dev);
551	dpaux->desc.pins = tegra_dpaux_pins;
552	dpaux->desc.npins = ARRAY_SIZE(tegra_dpaux_pins);
553	dpaux->desc.pctlops = &tegra_dpaux_pinctrl_ops;
554	dpaux->desc.pmxops = &tegra_dpaux_pinmux_ops;
555	dpaux->desc.owner = THIS_MODULE;
556
557	dpaux->pinctrl = devm_pinctrl_register(&pdev->dev, &dpaux->desc, dpaux);
558	if (IS_ERR(dpaux->pinctrl)) {
559		dev_err(&pdev->dev, "failed to register pincontrol\n");
560		return PTR_ERR(dpaux->pinctrl);
561	}
562#endif
563	/* enable and clear all interrupts */
564	value = DPAUX_INTR_AUX_DONE | DPAUX_INTR_IRQ_EVENT |
565		DPAUX_INTR_UNPLUG_EVENT | DPAUX_INTR_PLUG_EVENT;
566	tegra_dpaux_writel(dpaux, value, DPAUX_INTR_EN_AUX);
567	tegra_dpaux_writel(dpaux, value, DPAUX_INTR_AUX);
568
569	mutex_lock(&dpaux_lock);
570	list_add_tail(&dpaux->list, &dpaux_list);
571	mutex_unlock(&dpaux_lock);
572
573	return 0;
574}
575
576static int tegra_dpaux_remove(struct platform_device *pdev)
577{
578	struct tegra_dpaux *dpaux = platform_get_drvdata(pdev);
579
580	cancel_work_sync(&dpaux->work);
581
582	/* make sure pads are powered down when not in use */
583	tegra_dpaux_pad_power_down(dpaux);
584
585	pm_runtime_put_sync(&pdev->dev);
586	pm_runtime_disable(&pdev->dev);
587
 
 
588	mutex_lock(&dpaux_lock);
589	list_del(&dpaux->list);
590	mutex_unlock(&dpaux_lock);
591
592	return 0;
593}
594
595#ifdef CONFIG_PM
596static int tegra_dpaux_suspend(struct device *dev)
597{
598	struct tegra_dpaux *dpaux = dev_get_drvdata(dev);
599	int err = 0;
600
601	if (dpaux->rst) {
602		err = reset_control_assert(dpaux->rst);
603		if (err < 0) {
604			dev_err(dev, "failed to assert reset: %d\n", err);
605			return err;
606		}
607	}
608
609	usleep_range(1000, 2000);
610
611	clk_disable_unprepare(dpaux->clk_parent);
612	clk_disable_unprepare(dpaux->clk);
613
614	return err;
615}
616
617static int tegra_dpaux_resume(struct device *dev)
618{
619	struct tegra_dpaux *dpaux = dev_get_drvdata(dev);
620	int err;
621
622	err = clk_prepare_enable(dpaux->clk);
623	if (err < 0) {
624		dev_err(dev, "failed to enable clock: %d\n", err);
625		return err;
626	}
627
628	err = clk_prepare_enable(dpaux->clk_parent);
629	if (err < 0) {
630		dev_err(dev, "failed to enable parent clock: %d\n", err);
631		goto disable_clk;
632	}
633
634	usleep_range(1000, 2000);
635
636	if (dpaux->rst) {
637		err = reset_control_deassert(dpaux->rst);
638		if (err < 0) {
639			dev_err(dev, "failed to deassert reset: %d\n", err);
640			goto disable_parent;
641		}
642
643		usleep_range(1000, 2000);
644	}
645
646	return 0;
647
648disable_parent:
649	clk_disable_unprepare(dpaux->clk_parent);
650disable_clk:
651	clk_disable_unprepare(dpaux->clk);
652	return err;
653}
654#endif
655
656static const struct dev_pm_ops tegra_dpaux_pm_ops = {
657	SET_RUNTIME_PM_OPS(tegra_dpaux_suspend, tegra_dpaux_resume, NULL)
658};
659
660static const struct tegra_dpaux_soc tegra124_dpaux_soc = {
661	.cmh = 0x02,
662	.drvz = 0x04,
663	.drvi = 0x18,
664};
665
666static const struct tegra_dpaux_soc tegra210_dpaux_soc = {
667	.cmh = 0x02,
668	.drvz = 0x04,
669	.drvi = 0x30,
670};
671
672static const struct tegra_dpaux_soc tegra194_dpaux_soc = {
673	.cmh = 0x02,
674	.drvz = 0x04,
675	.drvi = 0x2c,
676};
677
678static const struct of_device_id tegra_dpaux_of_match[] = {
679	{ .compatible = "nvidia,tegra194-dpaux", .data = &tegra194_dpaux_soc },
680	{ .compatible = "nvidia,tegra186-dpaux", .data = &tegra210_dpaux_soc },
681	{ .compatible = "nvidia,tegra210-dpaux", .data = &tegra210_dpaux_soc },
682	{ .compatible = "nvidia,tegra124-dpaux", .data = &tegra124_dpaux_soc },
683	{ },
684};
685MODULE_DEVICE_TABLE(of, tegra_dpaux_of_match);
686
687struct platform_driver tegra_dpaux_driver = {
688	.driver = {
689		.name = "tegra-dpaux",
690		.of_match_table = tegra_dpaux_of_match,
691		.pm = &tegra_dpaux_pm_ops,
692	},
693	.probe = tegra_dpaux_probe,
694	.remove = tegra_dpaux_remove,
695};
696
697struct drm_dp_aux *drm_dp_aux_find_by_of_node(struct device_node *np)
698{
699	struct tegra_dpaux *dpaux;
700
701	mutex_lock(&dpaux_lock);
702
703	list_for_each_entry(dpaux, &dpaux_list, list)
704		if (np == dpaux->dev->of_node) {
705			mutex_unlock(&dpaux_lock);
706			return &dpaux->aux;
707		}
708
709	mutex_unlock(&dpaux_lock);
710
711	return NULL;
712}
713
714int drm_dp_aux_attach(struct drm_dp_aux *aux, struct tegra_output *output)
715{
716	struct tegra_dpaux *dpaux = to_dpaux(aux);
717	unsigned long timeout;
718	int err;
719
720	aux->drm_dev = output->connector.dev;
721	err = drm_dp_aux_register(aux);
 
 
722	if (err < 0)
723		return err;
724
725	output->connector.polled = DRM_CONNECTOR_POLL_HPD;
726	dpaux->output = output;
727
728	if (output->panel) {
729		enum drm_connector_status status;
730
731		if (dpaux->vdd) {
732			err = regulator_enable(dpaux->vdd);
733			if (err < 0)
734				return err;
735		}
736
737		timeout = jiffies + msecs_to_jiffies(250);
738
739		while (time_before(jiffies, timeout)) {
740			status = drm_dp_aux_detect(aux);
741
742			if (status == connector_status_connected)
743				break;
744
745			usleep_range(1000, 2000);
746		}
747
748		if (status != connector_status_connected)
749			return -ETIMEDOUT;
750	}
751
752	enable_irq(dpaux->irq);
753	return 0;
754}
755
756int drm_dp_aux_detach(struct drm_dp_aux *aux)
757{
758	struct tegra_dpaux *dpaux = to_dpaux(aux);
759	unsigned long timeout;
760	int err;
761
762	drm_dp_aux_unregister(aux);
763	disable_irq(dpaux->irq);
764
765	if (dpaux->output->panel) {
766		enum drm_connector_status status;
 
767
768		if (dpaux->vdd) {
769			err = regulator_disable(dpaux->vdd);
770			if (err < 0)
771				return err;
772		}
773
774		timeout = jiffies + msecs_to_jiffies(250);
775
776		while (time_before(jiffies, timeout)) {
777			status = drm_dp_aux_detect(aux);
778
779			if (status == connector_status_disconnected)
780				break;
781
782			usleep_range(1000, 2000);
783		}
784
785		if (status != connector_status_disconnected)
786			return -ETIMEDOUT;
787
788		dpaux->output = NULL;
789	}
790
791	return 0;
792}
793
794enum drm_connector_status drm_dp_aux_detect(struct drm_dp_aux *aux)
795{
796	struct tegra_dpaux *dpaux = to_dpaux(aux);
797	u32 value;
798
799	value = tegra_dpaux_readl(dpaux, DPAUX_DP_AUXSTAT);
800
801	if (value & DPAUX_DP_AUXSTAT_HPD_STATUS)
802		return connector_status_connected;
803
804	return connector_status_disconnected;
805}
806
807int drm_dp_aux_enable(struct drm_dp_aux *aux)
808{
809	struct tegra_dpaux *dpaux = to_dpaux(aux);
810
811	return tegra_dpaux_pad_config(dpaux, DPAUX_PADCTL_FUNC_AUX);
812}
813
814int drm_dp_aux_disable(struct drm_dp_aux *aux)
815{
816	struct tegra_dpaux *dpaux = to_dpaux(aux);
817
818	tegra_dpaux_pad_power_down(dpaux);
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
819
820	return 0;
821}