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 enum drm_mode_status thc63_mode_valid(struct drm_bridge *bridge, 49 const struct drm_display_mode *mode) 50 { 51 /* 52 * The THC63LVD1024 clock frequency range is 8 to 135 MHz in single-in 53 * mode. Note that the limits are different in dual-in, single-out mode, 54 * and will need to be adjusted accordingly. 55 */ 56 if (mode->clock < 8000) 57 return MODE_CLOCK_LOW; 58 59 if (mode->clock > 135000) 60 return MODE_CLOCK_HIGH; 61 62 return MODE_OK; 63 } 64 65 static void thc63_enable(struct drm_bridge *bridge) 66 { 67 struct thc63_dev *thc63 = to_thc63(bridge); 68 int ret; 69 70 ret = regulator_enable(thc63->vcc); 71 if (ret) { 72 dev_err(thc63->dev, 73 "Failed to enable regulator \"vcc\": %d\n", ret); 74 return; 75 } 76 77 gpiod_set_value(thc63->pdwn, 0); 78 gpiod_set_value(thc63->oe, 1); 79 } 80 81 static void thc63_disable(struct drm_bridge *bridge) 82 { 83 struct thc63_dev *thc63 = to_thc63(bridge); 84 int ret; 85 86 gpiod_set_value(thc63->oe, 0); 87 gpiod_set_value(thc63->pdwn, 1); 88 89 ret = regulator_disable(thc63->vcc); 90 if (ret) 91 dev_err(thc63->dev, 92 "Failed to disable regulator \"vcc\": %d\n", ret); 93 } 94 95 static const struct drm_bridge_funcs thc63_bridge_func = { 96 .attach = thc63_attach, 97 .mode_valid = thc63_mode_valid, 98 .enable = thc63_enable, 99 .disable = thc63_disable, 100 }; 101 102 static int thc63_parse_dt(struct thc63_dev *thc63) 103 { 104 struct device_node *thc63_out; 105 struct device_node *remote; 106 107 thc63_out = of_graph_get_endpoint_by_regs(thc63->dev->of_node, 108 THC63_RGB_OUT0, -1); 109 if (!thc63_out) { 110 dev_err(thc63->dev, "Missing endpoint in port@%u\n", 111 THC63_RGB_OUT0); 112 return -ENODEV; 113 } 114 115 remote = of_graph_get_remote_port_parent(thc63_out); 116 of_node_put(thc63_out); 117 if (!remote) { 118 dev_err(thc63->dev, "Endpoint in port@%u unconnected\n", 119 THC63_RGB_OUT0); 120 return -ENODEV; 121 } 122 123 if (!of_device_is_available(remote)) { 124 dev_err(thc63->dev, "port@%u remote endpoint is disabled\n", 125 THC63_RGB_OUT0); 126 of_node_put(remote); 127 return -ENODEV; 128 } 129 130 thc63->next = of_drm_find_bridge(remote); 131 of_node_put(remote); 132 if (!thc63->next) 133 return -EPROBE_DEFER; 134 135 return 0; 136 } 137 138 static int thc63_gpio_init(struct thc63_dev *thc63) 139 { 140 thc63->oe = devm_gpiod_get_optional(thc63->dev, "oe", GPIOD_OUT_LOW); 141 if (IS_ERR(thc63->oe)) { 142 dev_err(thc63->dev, "Unable to get \"oe-gpios\": %ld\n", 143 PTR_ERR(thc63->oe)); 144 return PTR_ERR(thc63->oe); 145 } 146 147 thc63->pdwn = devm_gpiod_get_optional(thc63->dev, "powerdown", 148 GPIOD_OUT_HIGH); 149 if (IS_ERR(thc63->pdwn)) { 150 dev_err(thc63->dev, "Unable to get \"powerdown-gpios\": %ld\n", 151 PTR_ERR(thc63->pdwn)); 152 return PTR_ERR(thc63->pdwn); 153 } 154 155 return 0; 156 } 157 158 static int thc63_probe(struct platform_device *pdev) 159 { 160 struct thc63_dev *thc63; 161 int ret; 162 163 thc63 = devm_kzalloc(&pdev->dev, sizeof(*thc63), GFP_KERNEL); 164 if (!thc63) 165 return -ENOMEM; 166 167 thc63->dev = &pdev->dev; 168 platform_set_drvdata(pdev, thc63); 169 170 thc63->vcc = devm_regulator_get_optional(thc63->dev, "vcc"); 171 if (IS_ERR(thc63->vcc)) { 172 if (PTR_ERR(thc63->vcc) == -EPROBE_DEFER) 173 return -EPROBE_DEFER; 174 175 dev_err(thc63->dev, "Unable to get \"vcc\" supply: %ld\n", 176 PTR_ERR(thc63->vcc)); 177 return PTR_ERR(thc63->vcc); 178 } 179 180 ret = thc63_gpio_init(thc63); 181 if (ret) 182 return ret; 183 184 ret = thc63_parse_dt(thc63); 185 if (ret) 186 return ret; 187 188 thc63->bridge.driver_private = thc63; 189 thc63->bridge.of_node = pdev->dev.of_node; 190 thc63->bridge.funcs = &thc63_bridge_func; 191 192 drm_bridge_add(&thc63->bridge); 193 194 return 0; 195 } 196 197 static int thc63_remove(struct platform_device *pdev) 198 { 199 struct thc63_dev *thc63 = platform_get_drvdata(pdev); 200 201 drm_bridge_remove(&thc63->bridge); 202 203 return 0; 204 } 205 206 static const struct of_device_id thc63_match[] = { 207 { .compatible = "thine,thc63lvd1024", }, 208 { }, 209 }; 210 MODULE_DEVICE_TABLE(of, thc63_match); 211 212 static struct platform_driver thc63_driver = { 213 .probe = thc63_probe, 214 .remove = thc63_remove, 215 .driver = { 216 .name = "thc63lvd1024", 217 .of_match_table = thc63_match, 218 }, 219 }; 220 module_platform_driver(thc63_driver); 221 222 MODULE_AUTHOR("Jacopo Mondi <jacopo@jmondi.org>"); 223 MODULE_DESCRIPTION("Thine THC63LVD1024 LVDS decoder DRM bridge driver"); 224 MODULE_LICENSE("GPL v2"); 225