kernel/drivers/gpu/drm/tegra/output.c

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