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 struct drm_bridge_timings timings; 36 }; 37 38 static inline struct thc63_dev *to_thc63(struct drm_bridge *bridge) 39 { 40 return container_of(bridge, struct thc63_dev, bridge); 41 } 42 43 static int thc63_attach(struct drm_bridge *bridge) 44 { 45 struct thc63_dev *thc63 = to_thc63(bridge); 46 47 return drm_bridge_attach(bridge->encoder, thc63->next, bridge); 48 } 49 50 static enum drm_mode_status thc63_mode_valid(struct drm_bridge *bridge, 51 const struct drm_display_mode *mode) 52 { 53 struct thc63_dev *thc63 = to_thc63(bridge); 54 unsigned int min_freq; 55 unsigned int max_freq; 56 57 /* 58 * The THC63LVD1024 pixel rate range is 8 to 135 MHz in all modes but 59 * dual-in, single-out where it is 40 to 150 MHz. As dual-in, dual-out 60 * isn't supported by the driver yet, simply derive the limits from the 61 * input mode. 62 */ 63 if (thc63->timings.dual_link) { 64 min_freq = 40000; 65 max_freq = 150000; 66 } else { 67 min_freq = 8000; 68 max_freq = 135000; 69 } 70 71 if (mode->clock < min_freq) 72 return MODE_CLOCK_LOW; 73 74 if (mode->clock > max_freq) 75 return MODE_CLOCK_HIGH; 76 77 return MODE_OK; 78 } 79 80 static void thc63_enable(struct drm_bridge *bridge) 81 { 82 struct thc63_dev *thc63 = to_thc63(bridge); 83 int ret; 84 85 ret = regulator_enable(thc63->vcc); 86 if (ret) { 87 dev_err(thc63->dev, 88 "Failed to enable regulator \"vcc\": %d\n", ret); 89 return; 90 } 91 92 gpiod_set_value(thc63->pdwn, 0); 93 gpiod_set_value(thc63->oe, 1); 94 } 95 96 static void thc63_disable(struct drm_bridge *bridge) 97 { 98 struct thc63_dev *thc63 = to_thc63(bridge); 99 int ret; 100 101 gpiod_set_value(thc63->oe, 0); 102 gpiod_set_value(thc63->pdwn, 1); 103 104 ret = regulator_disable(thc63->vcc); 105 if (ret) 106 dev_err(thc63->dev, 107 "Failed to disable regulator \"vcc\": %d\n", ret); 108 } 109 110 static const struct drm_bridge_funcs thc63_bridge_func = { 111 .attach = thc63_attach, 112 .mode_valid = thc63_mode_valid, 113 .enable = thc63_enable, 114 .disable = thc63_disable, 115 }; 116 117 static int thc63_parse_dt(struct thc63_dev *thc63) 118 { 119 struct device_node *endpoint; 120 struct device_node *remote; 121 122 endpoint = of_graph_get_endpoint_by_regs(thc63->dev->of_node, 123 THC63_RGB_OUT0, -1); 124 if (!endpoint) { 125 dev_err(thc63->dev, "Missing endpoint in port@%u\n", 126 THC63_RGB_OUT0); 127 return -ENODEV; 128 } 129 130 remote = of_graph_get_remote_port_parent(endpoint); 131 of_node_put(endpoint); 132 if (!remote) { 133 dev_err(thc63->dev, "Endpoint in port@%u unconnected\n", 134 THC63_RGB_OUT0); 135 return -ENODEV; 136 } 137 138 if (!of_device_is_available(remote)) { 139 dev_err(thc63->dev, "port@%u remote endpoint is disabled\n", 140 THC63_RGB_OUT0); 141 of_node_put(remote); 142 return -ENODEV; 143 } 144 145 thc63->next = of_drm_find_bridge(remote); 146 of_node_put(remote); 147 if (!thc63->next) 148 return -EPROBE_DEFER; 149 150 endpoint = of_graph_get_endpoint_by_regs(thc63->dev->of_node, 151 THC63_LVDS_IN1, -1); 152 if (endpoint) { 153 remote = of_graph_get_remote_port_parent(endpoint); 154 of_node_put(endpoint); 155 156 if (remote) { 157 if (of_device_is_available(remote)) 158 thc63->timings.dual_link = true; 159 of_node_put(remote); 160 } 161 } 162 163 dev_dbg(thc63->dev, "operating in %s-link mode\n", 164 thc63->timings.dual_link ? "dual" : "single"); 165 166 return 0; 167 } 168 169 static int thc63_gpio_init(struct thc63_dev *thc63) 170 { 171 thc63->oe = devm_gpiod_get_optional(thc63->dev, "oe", GPIOD_OUT_LOW); 172 if (IS_ERR(thc63->oe)) { 173 dev_err(thc63->dev, "Unable to get \"oe-gpios\": %ld\n", 174 PTR_ERR(thc63->oe)); 175 return PTR_ERR(thc63->oe); 176 } 177 178 thc63->pdwn = devm_gpiod_get_optional(thc63->dev, "powerdown", 179 GPIOD_OUT_HIGH); 180 if (IS_ERR(thc63->pdwn)) { 181 dev_err(thc63->dev, "Unable to get \"powerdown-gpios\": %ld\n", 182 PTR_ERR(thc63->pdwn)); 183 return PTR_ERR(thc63->pdwn); 184 } 185 186 return 0; 187 } 188 189 static int thc63_probe(struct platform_device *pdev) 190 { 191 struct thc63_dev *thc63; 192 int ret; 193 194 thc63 = devm_kzalloc(&pdev->dev, sizeof(*thc63), GFP_KERNEL); 195 if (!thc63) 196 return -ENOMEM; 197 198 thc63->dev = &pdev->dev; 199 platform_set_drvdata(pdev, thc63); 200 201 thc63->vcc = devm_regulator_get_optional(thc63->dev, "vcc"); 202 if (IS_ERR(thc63->vcc)) { 203 if (PTR_ERR(thc63->vcc) == -EPROBE_DEFER) 204 return -EPROBE_DEFER; 205 206 dev_err(thc63->dev, "Unable to get \"vcc\" supply: %ld\n", 207 PTR_ERR(thc63->vcc)); 208 return PTR_ERR(thc63->vcc); 209 } 210 211 ret = thc63_gpio_init(thc63); 212 if (ret) 213 return ret; 214 215 ret = thc63_parse_dt(thc63); 216 if (ret) 217 return ret; 218 219 thc63->bridge.driver_private = thc63; 220 thc63->bridge.of_node = pdev->dev.of_node; 221 thc63->bridge.funcs = &thc63_bridge_func; 222 thc63->bridge.timings = &thc63->timings; 223 224 drm_bridge_add(&thc63->bridge); 225 226 return 0; 227 } 228 229 static int thc63_remove(struct platform_device *pdev) 230 { 231 struct thc63_dev *thc63 = platform_get_drvdata(pdev); 232 233 drm_bridge_remove(&thc63->bridge); 234 235 return 0; 236 } 237 238 static const struct of_device_id thc63_match[] = { 239 { .compatible = "thine,thc63lvd1024", }, 240 { }, 241 }; 242 MODULE_DEVICE_TABLE(of, thc63_match); 243 244 static struct platform_driver thc63_driver = { 245 .probe = thc63_probe, 246 .remove = thc63_remove, 247 .driver = { 248 .name = "thc63lvd1024", 249 .of_match_table = thc63_match, 250 }, 251 }; 252 module_platform_driver(thc63_driver); 253 254 MODULE_AUTHOR("Jacopo Mondi <jacopo@jmondi.org>"); 255 MODULE_DESCRIPTION("Thine THC63LVD1024 LVDS decoder DRM bridge driver"); 256 MODULE_LICENSE("GPL v2"); 257