1/*
  2 * Copyright (C) 2012 Avionic Design GmbH
  3 * Copyright (C) 2012 NVIDIA CORPORATION.  All rights reserved.
  4 *
  5 * This program is free software; you can redistribute it and/or modify
  6 * it under the terms of the GNU General Public License version 2 as
  7 * published by the Free Software Foundation.
  8 */
  9
 10#include <drm/drm_atomic_helper.h>
 11#include <drm/drm_panel.h>
 12#include "drm.h"
 13
 14int tegra_output_connector_get_modes(struct drm_connector *connector)
 15{
 16	struct tegra_output *output = connector_to_output(connector);
 17	struct edid *edid = NULL;
 18	int err = 0;
 19
 20	/*
 21	 * If the panel provides one or more modes, use them exclusively and
 22	 * ignore any other means of obtaining a mode.
 23	 */
 24	if (output->panel) {
 25		err = output->panel->funcs->get_modes(output->panel);
 26		if (err > 0)
 27			return err;
 28	}
 29
 30	if (output->edid)
 31		edid = kmemdup(output->edid, sizeof(*edid), GFP_KERNEL);
 32	else if (output->ddc)
 33		edid = drm_get_edid(connector, output->ddc);
 34
 35	drm_mode_connector_update_edid_property(connector, edid);
 36
 37	if (edid) {
 38		err = drm_add_edid_modes(connector, edid);
 39		kfree(edid);
 40	}
 41
 42	return err;
 43}
 44
 45struct drm_encoder *
 46tegra_output_connector_best_encoder(struct drm_connector *connector)
 47{
 48	struct tegra_output *output = connector_to_output(connector);
 49
 50	return &output->encoder;
 51}
 52
 53enum drm_connector_status
 54tegra_output_connector_detect(struct drm_connector *connector, bool force)
 55{
 56	struct tegra_output *output = connector_to_output(connector);
 57	enum drm_connector_status status = connector_status_unknown;
 58
 59	if (gpio_is_valid(output->hpd_gpio)) {
 60		if (output->hpd_gpio_flags & OF_GPIO_ACTIVE_LOW) {
 61			if (gpio_get_value(output->hpd_gpio) != 0)
 62				status = connector_status_disconnected;
 63			else
 64				status = connector_status_connected;
 65		} else {
 66			if (gpio_get_value(output->hpd_gpio) == 0)
 67				status = connector_status_disconnected;
 68			else
 69				status = connector_status_connected;
 70		}
 71	} else {
 72		if (!output->panel)
 73			status = connector_status_disconnected;
 74		else
 75			status = connector_status_connected;
 76	}
 77
 78	return status;
 79}
 80
 81void tegra_output_connector_destroy(struct drm_connector *connector)
 82{
 83	drm_connector_unregister(connector);
 84	drm_connector_cleanup(connector);
 85}
 86
 87void tegra_output_encoder_destroy(struct drm_encoder *encoder)
 88{
 89	drm_encoder_cleanup(encoder);
 90}
 91
 92static irqreturn_t hpd_irq(int irq, void *data)
 93{
 94	struct tegra_output *output = data;
 95
 96	if (output->connector.dev)
 97		drm_helper_hpd_irq_event(output->connector.dev);
 98
 99	return IRQ_HANDLED;
100}
101
102int tegra_output_probe(struct tegra_output *output)
103{
104	struct device_node *ddc, *panel;
105	int err, size;
106
107	if (!output->of_node)
108		output->of_node = output->dev->of_node;
109
110	panel = of_parse_phandle(output->of_node, "nvidia,panel", 0);
111	if (panel) {
112		output->panel = of_drm_find_panel(panel);
113		if (!output->panel)
114			return -EPROBE_DEFER;
115
116		of_node_put(panel);
117	}
118
119	output->edid = of_get_property(output->of_node, "nvidia,edid", &size);
120
121	ddc = of_parse_phandle(output->of_node, "nvidia,ddc-i2c-bus", 0);
122	if (ddc) {
123		output->ddc = of_find_i2c_adapter_by_node(ddc);
124		if (!output->ddc) {
125			err = -EPROBE_DEFER;
126			of_node_put(ddc);
127			return err;
128		}
129
130		of_node_put(ddc);
131	}
132
133	output->hpd_gpio = of_get_named_gpio_flags(output->of_node,
134						   "nvidia,hpd-gpio", 0,
135						   &output->hpd_gpio_flags);
136	if (gpio_is_valid(output->hpd_gpio)) {
137		unsigned long flags;
138
139		err = gpio_request_one(output->hpd_gpio, GPIOF_DIR_IN,
140				       "HDMI hotplug detect");
141		if (err < 0) {
142			dev_err(output->dev, "gpio_request_one(): %d\n", err);
143			return err;
144		}
145
146		err = gpio_to_irq(output->hpd_gpio);
147		if (err < 0) {
148			dev_err(output->dev, "gpio_to_irq(): %d\n", err);
149			gpio_free(output->hpd_gpio);
150			return err;
151		}
152
153		output->hpd_irq = err;
154
155		flags = IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING |
156			IRQF_ONESHOT;
157
158		err = request_threaded_irq(output->hpd_irq, NULL, hpd_irq,
159					   flags, "hpd", output);
160		if (err < 0) {
161			dev_err(output->dev, "failed to request IRQ#%u: %d\n",
162				output->hpd_irq, err);
163			gpio_free(output->hpd_gpio);
164			return err;
165		}
166
167		output->connector.polled = DRM_CONNECTOR_POLL_HPD;
168
169		/*
170		 * Disable the interrupt until the connector has been
171		 * initialized to avoid a race in the hotplug interrupt
172		 * handler.
173		 */
174		disable_irq(output->hpd_irq);
175	}
176
177	return 0;
178}
179
180void tegra_output_remove(struct tegra_output *output)
181{
182	if (gpio_is_valid(output->hpd_gpio)) {
183		free_irq(output->hpd_irq, output);
184		gpio_free(output->hpd_gpio);
185	}
186
187	if (output->ddc)
188		put_device(&output->ddc->dev);
189}
190
191int tegra_output_init(struct drm_device *drm, struct tegra_output *output)
192{
193	int err;
194
195	if (output->panel) {
196		err = drm_panel_attach(output->panel, &output->connector);
197		if (err < 0)
198			return err;
199	}
200
201	/*
202	 * The connector is now registered and ready to receive hotplug events
203	 * so the hotplug interrupt can be enabled.
204	 */
205	if (gpio_is_valid(output->hpd_gpio))
206		enable_irq(output->hpd_irq);
207
208	return 0;
209}
210
211void tegra_output_exit(struct tegra_output *output)
212{
213	/*
214	 * The connector is going away, so the interrupt must be disabled to
215	 * prevent the hotplug interrupt handler from potentially crashing.
216	 */
217	if (gpio_is_valid(output->hpd_gpio))
218		disable_irq(output->hpd_irq);
219
220	if (output->panel)
221		drm_panel_detach(output->panel);
222}