1 // SPDX-License-Identifier: GPL-2.0-or-later 2 /* 3 * Copyright (C) 2019 Renesas Electronics Corporation 4 * Copyright (C) 2016 Laurent Pinchart <laurent.pinchart@ideasonboard.com> 5 */ 6 7 #include <linux/gpio/consumer.h> 8 #include <linux/module.h> 9 #include <linux/of.h> 10 #include <linux/of_device.h> 11 #include <linux/of_graph.h> 12 #include <linux/platform_device.h> 13 #include <linux/regulator/consumer.h> 14 15 #include <drm/drm_bridge.h> 16 #include <drm/drm_panel.h> 17 18 struct lvds_codec { 19 struct device *dev; 20 struct drm_bridge bridge; 21 struct drm_bridge *panel_bridge; 22 struct regulator *vcc; 23 struct gpio_desc *powerdown_gpio; 24 u32 connector_type; 25 }; 26 27 static inline struct lvds_codec *to_lvds_codec(struct drm_bridge *bridge) 28 { 29 return container_of(bridge, struct lvds_codec, bridge); 30 } 31 32 static int lvds_codec_attach(struct drm_bridge *bridge, 33 enum drm_bridge_attach_flags flags) 34 { 35 struct lvds_codec *lvds_codec = to_lvds_codec(bridge); 36 37 return drm_bridge_attach(bridge->encoder, lvds_codec->panel_bridge, 38 bridge, flags); 39 } 40 41 static void lvds_codec_enable(struct drm_bridge *bridge) 42 { 43 struct lvds_codec *lvds_codec = to_lvds_codec(bridge); 44 int ret; 45 46 ret = regulator_enable(lvds_codec->vcc); 47 if (ret) { 48 dev_err(lvds_codec->dev, 49 "Failed to enable regulator \"vcc\": %d\n", ret); 50 return; 51 } 52 53 if (lvds_codec->powerdown_gpio) 54 gpiod_set_value_cansleep(lvds_codec->powerdown_gpio, 0); 55 } 56 57 static void lvds_codec_disable(struct drm_bridge *bridge) 58 { 59 struct lvds_codec *lvds_codec = to_lvds_codec(bridge); 60 int ret; 61 62 if (lvds_codec->powerdown_gpio) 63 gpiod_set_value_cansleep(lvds_codec->powerdown_gpio, 1); 64 65 ret = regulator_disable(lvds_codec->vcc); 66 if (ret) 67 dev_err(lvds_codec->dev, 68 "Failed to disable regulator \"vcc\": %d\n", ret); 69 } 70 71 static const struct drm_bridge_funcs funcs = { 72 .attach = lvds_codec_attach, 73 .enable = lvds_codec_enable, 74 .disable = lvds_codec_disable, 75 }; 76 77 static int lvds_codec_probe(struct platform_device *pdev) 78 { 79 struct device *dev = &pdev->dev; 80 struct device_node *panel_node; 81 struct drm_panel *panel; 82 struct lvds_codec *lvds_codec; 83 84 lvds_codec = devm_kzalloc(dev, sizeof(*lvds_codec), GFP_KERNEL); 85 if (!lvds_codec) 86 return -ENOMEM; 87 88 lvds_codec->dev = &pdev->dev; 89 lvds_codec->connector_type = (uintptr_t)of_device_get_match_data(dev); 90 91 lvds_codec->vcc = devm_regulator_get(lvds_codec->dev, "power"); 92 if (IS_ERR(lvds_codec->vcc)) 93 return dev_err_probe(dev, PTR_ERR(lvds_codec->vcc), 94 "Unable to get \"vcc\" supply\n"); 95 96 lvds_codec->powerdown_gpio = devm_gpiod_get_optional(dev, "powerdown", 97 GPIOD_OUT_HIGH); 98 if (IS_ERR(lvds_codec->powerdown_gpio)) 99 return dev_err_probe(dev, PTR_ERR(lvds_codec->powerdown_gpio), 100 "powerdown GPIO failure\n"); 101 102 /* Locate the panel DT node. */ 103 panel_node = of_graph_get_remote_node(dev->of_node, 1, 0); 104 if (!panel_node) { 105 dev_dbg(dev, "panel DT node not found\n"); 106 return -ENXIO; 107 } 108 109 panel = of_drm_find_panel(panel_node); 110 of_node_put(panel_node); 111 if (IS_ERR(panel)) { 112 dev_dbg(dev, "panel not found, deferring probe\n"); 113 return PTR_ERR(panel); 114 } 115 116 lvds_codec->panel_bridge = 117 devm_drm_panel_bridge_add_typed(dev, panel, 118 lvds_codec->connector_type); 119 if (IS_ERR(lvds_codec->panel_bridge)) 120 return PTR_ERR(lvds_codec->panel_bridge); 121 122 /* 123 * The panel_bridge bridge is attached to the panel's of_node, 124 * but we need a bridge attached to our of_node for our user 125 * to look up. 126 */ 127 lvds_codec->bridge.of_node = dev->of_node; 128 lvds_codec->bridge.funcs = &funcs; 129 drm_bridge_add(&lvds_codec->bridge); 130 131 platform_set_drvdata(pdev, lvds_codec); 132 133 return 0; 134 } 135 136 static int lvds_codec_remove(struct platform_device *pdev) 137 { 138 struct lvds_codec *lvds_codec = platform_get_drvdata(pdev); 139 140 drm_bridge_remove(&lvds_codec->bridge); 141 142 return 0; 143 } 144 145 static const struct of_device_id lvds_codec_match[] = { 146 { 147 .compatible = "lvds-decoder", 148 .data = (void *)DRM_MODE_CONNECTOR_DPI, 149 }, 150 { 151 .compatible = "lvds-encoder", 152 .data = (void *)DRM_MODE_CONNECTOR_LVDS, 153 }, 154 { 155 .compatible = "thine,thc63lvdm83d", 156 .data = (void *)DRM_MODE_CONNECTOR_LVDS, 157 }, 158 {}, 159 }; 160 MODULE_DEVICE_TABLE(of, lvds_codec_match); 161 162 static struct platform_driver lvds_codec_driver = { 163 .probe = lvds_codec_probe, 164 .remove = lvds_codec_remove, 165 .driver = { 166 .name = "lvds-codec", 167 .of_match_table = lvds_codec_match, 168 }, 169 }; 170 module_platform_driver(lvds_codec_driver); 171 172 MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>"); 173 MODULE_DESCRIPTION("LVDS encoders and decoders"); 174 MODULE_LICENSE("GPL"); 175