1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * THC63LVD1024 LVDS to parallel data DRM bridge driver. 4 * 5 * Copyright (C) 2018 Jacopo Mondi <jacopo+renesas@jmondi.org> 6 */ 7 8 #include <drm/drmP.h> 9 #include <drm/drm_bridge.h> 10 #include <drm/drm_panel.h> 11 12 #include <linux/gpio/consumer.h> 13 #include <linux/of_graph.h> 14 #include <linux/regulator/consumer.h> 15 #include <linux/slab.h> 16 17 enum thc63_ports { 18 THC63_LVDS_IN0, 19 THC63_LVDS_IN1, 20 THC63_RGB_OUT0, 21 THC63_RGB_OUT1, 22 }; 23 24 struct thc63_dev { 25 struct device *dev; 26 27 struct regulator *vcc; 28 29 struct gpio_desc *pdwn; 30 struct gpio_desc *oe; 31 32 struct drm_bridge bridge; 33 struct drm_bridge *next; 34 }; 35 36 static inline struct thc63_dev *to_thc63(struct drm_bridge *bridge) 37 { 38 return container_of(bridge, struct thc63_dev, bridge); 39 } 40 41 static int thc63_attach(struct drm_bridge *bridge) 42 { 43 struct thc63_dev *thc63 = to_thc63(bridge); 44 45 return drm_bridge_attach(bridge->encoder, thc63->next, bridge); 46 } 47 48 static void thc63_enable(struct drm_bridge *bridge) 49 { 50 struct thc63_dev *thc63 = to_thc63(bridge); 51 int ret; 52 53 ret = regulator_enable(thc63->vcc); 54 if (ret) { 55 dev_err(thc63->dev, 56 "Failed to enable regulator \"vcc\": %d\n", ret); 57 return; 58 } 59 60 gpiod_set_value(thc63->pdwn, 0); 61 gpiod_set_value(thc63->oe, 1); 62 } 63 64 static void thc63_disable(struct drm_bridge *bridge) 65 { 66 struct thc63_dev *thc63 = to_thc63(bridge); 67 int ret; 68 69 gpiod_set_value(thc63->oe, 0); 70 gpiod_set_value(thc63->pdwn, 1); 71 72 ret = regulator_disable(thc63->vcc); 73 if (ret) 74 dev_err(thc63->dev, 75 "Failed to disable regulator \"vcc\": %d\n", ret); 76 } 77 78 static const struct drm_bridge_funcs thc63_bridge_func = { 79 .attach = thc63_attach, 80 .enable = thc63_enable, 81 .disable = thc63_disable, 82 }; 83 84 static int thc63_parse_dt(struct thc63_dev *thc63) 85 { 86 struct device_node *thc63_out; 87 struct device_node *remote; 88 89 thc63_out = of_graph_get_endpoint_by_regs(thc63->dev->of_node, 90 THC63_RGB_OUT0, -1); 91 if (!thc63_out) { 92 dev_err(thc63->dev, "Missing endpoint in port@%u\n", 93 THC63_RGB_OUT0); 94 return -ENODEV; 95 } 96 97 remote = of_graph_get_remote_port_parent(thc63_out); 98 of_node_put(thc63_out); 99 if (!remote) { 100 dev_err(thc63->dev, "Endpoint in port@%u unconnected\n", 101 THC63_RGB_OUT0); 102 return -ENODEV; 103 } 104 105 if (!of_device_is_available(remote)) { 106 dev_err(thc63->dev, "port@%u remote endpoint is disabled\n", 107 THC63_RGB_OUT0); 108 of_node_put(remote); 109 return -ENODEV; 110 } 111 112 thc63->next = of_drm_find_bridge(remote); 113 of_node_put(remote); 114 if (!thc63->next) 115 return -EPROBE_DEFER; 116 117 return 0; 118 } 119 120 static int thc63_gpio_init(struct thc63_dev *thc63) 121 { 122 thc63->oe = devm_gpiod_get_optional(thc63->dev, "oe", GPIOD_OUT_LOW); 123 if (IS_ERR(thc63->oe)) { 124 dev_err(thc63->dev, "Unable to get \"oe-gpios\": %ld\n", 125 PTR_ERR(thc63->oe)); 126 return PTR_ERR(thc63->oe); 127 } 128 129 thc63->pdwn = devm_gpiod_get_optional(thc63->dev, "powerdown", 130 GPIOD_OUT_HIGH); 131 if (IS_ERR(thc63->pdwn)) { 132 dev_err(thc63->dev, "Unable to get \"powerdown-gpios\": %ld\n", 133 PTR_ERR(thc63->pdwn)); 134 return PTR_ERR(thc63->pdwn); 135 } 136 137 return 0; 138 } 139 140 static int thc63_probe(struct platform_device *pdev) 141 { 142 struct thc63_dev *thc63; 143 int ret; 144 145 thc63 = devm_kzalloc(&pdev->dev, sizeof(*thc63), GFP_KERNEL); 146 if (!thc63) 147 return -ENOMEM; 148 149 thc63->dev = &pdev->dev; 150 platform_set_drvdata(pdev, thc63); 151 152 thc63->vcc = devm_regulator_get_optional(thc63->dev, "vcc"); 153 if (IS_ERR(thc63->vcc)) { 154 if (PTR_ERR(thc63->vcc) == -EPROBE_DEFER) 155 return -EPROBE_DEFER; 156 157 dev_err(thc63->dev, "Unable to get \"vcc\" supply: %ld\n", 158 PTR_ERR(thc63->vcc)); 159 return PTR_ERR(thc63->vcc); 160 } 161 162 ret = thc63_gpio_init(thc63); 163 if (ret) 164 return ret; 165 166 ret = thc63_parse_dt(thc63); 167 if (ret) 168 return ret; 169 170 thc63->bridge.driver_private = thc63; 171 thc63->bridge.of_node = pdev->dev.of_node; 172 thc63->bridge.funcs = &thc63_bridge_func; 173 174 drm_bridge_add(&thc63->bridge); 175 176 return 0; 177 } 178 179 static int thc63_remove(struct platform_device *pdev) 180 { 181 struct thc63_dev *thc63 = platform_get_drvdata(pdev); 182 183 drm_bridge_remove(&thc63->bridge); 184 185 return 0; 186 } 187 188 static const struct of_device_id thc63_match[] = { 189 { .compatible = "thine,thc63lvd1024", }, 190 { }, 191 }; 192 MODULE_DEVICE_TABLE(of, thc63_match); 193 194 static struct platform_driver thc63_driver = { 195 .probe = thc63_probe, 196 .remove = thc63_remove, 197 .driver = { 198 .name = "thc63lvd1024", 199 .of_match_table = thc63_match, 200 }, 201 }; 202 module_platform_driver(thc63_driver); 203 204 MODULE_AUTHOR("Jacopo Mondi <jacopo@jmondi.org>"); 205 MODULE_DESCRIPTION("Thine THC63LVD1024 LVDS decoder DRM bridge driver"); 206 MODULE_LICENSE("GPL v2"); 207