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1// SPDX-License-Identifier: GPL-2.02/*3 * THC63LVD1024 LVDS to parallel data DRM bridge driver.4 *5 * Copyright (C) 2018 Jacopo Mondi <jacopo+renesas@jmondi.org>6 */7 8#include <linux/gpio/consumer.h>9#include <linux/module.h>10#include <linux/of.h>11#include <linux/of_graph.h>12#include <linux/platform_device.h>13#include <linux/regulator/consumer.h>14#include <linux/slab.h>15 16#include <drm/drm_bridge.h>17#include <drm/drm_panel.h>18 19enum thc63_ports {20 THC63_LVDS_IN0,21 THC63_LVDS_IN1,22 THC63_RGB_OUT0,23 THC63_RGB_OUT1,24};25 26struct thc63_dev {27 struct device *dev;28 29 struct regulator *vcc;30 31 struct gpio_desc *pdwn;32 struct gpio_desc *oe;33 34 struct drm_bridge bridge;35 struct drm_bridge *next;36 37 struct drm_bridge_timings timings;38};39 40static inline struct thc63_dev *to_thc63(struct drm_bridge *bridge)41{42 return container_of(bridge, struct thc63_dev, bridge);43}44 45static int thc63_attach(struct drm_bridge *bridge,46 enum drm_bridge_attach_flags flags)47{48 struct thc63_dev *thc63 = to_thc63(bridge);49 50 return drm_bridge_attach(bridge->encoder, thc63->next, bridge, flags);51}52 53static enum drm_mode_status thc63_mode_valid(struct drm_bridge *bridge,54 const struct drm_display_info *info,55 const struct drm_display_mode *mode)56{57 struct thc63_dev *thc63 = to_thc63(bridge);58 unsigned int min_freq;59 unsigned int max_freq;60 61 /*62 * The THC63LVD1024 pixel rate range is 8 to 135 MHz in all modes but63 * dual-in, single-out where it is 40 to 150 MHz. As dual-in, dual-out64 * isn't supported by the driver yet, simply derive the limits from the65 * input mode.66 */67 if (thc63->timings.dual_link) {68 min_freq = 40000;69 max_freq = 150000;70 } else {71 min_freq = 8000;72 max_freq = 135000;73 }74 75 if (mode->clock < min_freq)76 return MODE_CLOCK_LOW;77 78 if (mode->clock > max_freq)79 return MODE_CLOCK_HIGH;80 81 return MODE_OK;82}83 84static void thc63_enable(struct drm_bridge *bridge)85{86 struct thc63_dev *thc63 = to_thc63(bridge);87 int ret;88 89 ret = regulator_enable(thc63->vcc);90 if (ret) {91 dev_err(thc63->dev,92 "Failed to enable regulator \"vcc\": %d\n", ret);93 return;94 }95 96 gpiod_set_value(thc63->pdwn, 0);97 gpiod_set_value(thc63->oe, 1);98}99 100static void thc63_disable(struct drm_bridge *bridge)101{102 struct thc63_dev *thc63 = to_thc63(bridge);103 int ret;104 105 gpiod_set_value(thc63->oe, 0);106 gpiod_set_value(thc63->pdwn, 1);107 108 ret = regulator_disable(thc63->vcc);109 if (ret)110 dev_err(thc63->dev,111 "Failed to disable regulator \"vcc\": %d\n", ret);112}113 114static const struct drm_bridge_funcs thc63_bridge_func = {115 .attach = thc63_attach,116 .mode_valid = thc63_mode_valid,117 .enable = thc63_enable,118 .disable = thc63_disable,119};120 121static int thc63_parse_dt(struct thc63_dev *thc63)122{123 struct device_node *endpoint;124 struct device_node *remote;125 126 remote = of_graph_get_remote_node(thc63->dev->of_node,127 THC63_RGB_OUT0, -1);128 if (!remote) {129 dev_err(thc63->dev, "No remote endpoint for port@%u\n",130 THC63_RGB_OUT0);131 return -ENODEV;132 }133 134 thc63->next = of_drm_find_bridge(remote);135 of_node_put(remote);136 if (!thc63->next)137 return -EPROBE_DEFER;138 139 endpoint = of_graph_get_endpoint_by_regs(thc63->dev->of_node,140 THC63_LVDS_IN1, -1);141 if (endpoint) {142 remote = of_graph_get_remote_port_parent(endpoint);143 of_node_put(endpoint);144 145 if (remote) {146 if (of_device_is_available(remote))147 thc63->timings.dual_link = true;148 of_node_put(remote);149 }150 }151 152 dev_dbg(thc63->dev, "operating in %s-link mode\n",153 thc63->timings.dual_link ? "dual" : "single");154 155 return 0;156}157 158static int thc63_gpio_init(struct thc63_dev *thc63)159{160 thc63->oe = devm_gpiod_get_optional(thc63->dev, "oe", GPIOD_OUT_LOW);161 if (IS_ERR(thc63->oe)) {162 dev_err(thc63->dev, "Unable to get \"oe-gpios\": %ld\n",163 PTR_ERR(thc63->oe));164 return PTR_ERR(thc63->oe);165 }166 167 thc63->pdwn = devm_gpiod_get_optional(thc63->dev, "powerdown",168 GPIOD_OUT_HIGH);169 if (IS_ERR(thc63->pdwn)) {170 dev_err(thc63->dev, "Unable to get \"powerdown-gpios\": %ld\n",171 PTR_ERR(thc63->pdwn));172 return PTR_ERR(thc63->pdwn);173 }174 175 return 0;176}177 178static int thc63_probe(struct platform_device *pdev)179{180 struct thc63_dev *thc63;181 int ret;182 183 thc63 = devm_kzalloc(&pdev->dev, sizeof(*thc63), GFP_KERNEL);184 if (!thc63)185 return -ENOMEM;186 187 thc63->dev = &pdev->dev;188 platform_set_drvdata(pdev, thc63);189 190 thc63->vcc = devm_regulator_get(thc63->dev, "vcc");191 if (IS_ERR(thc63->vcc)) {192 if (PTR_ERR(thc63->vcc) == -EPROBE_DEFER)193 return -EPROBE_DEFER;194 195 dev_err(thc63->dev, "Unable to get \"vcc\" supply: %ld\n",196 PTR_ERR(thc63->vcc));197 return PTR_ERR(thc63->vcc);198 }199 200 ret = thc63_gpio_init(thc63);201 if (ret)202 return ret;203 204 ret = thc63_parse_dt(thc63);205 if (ret)206 return ret;207 208 thc63->bridge.driver_private = thc63;209 thc63->bridge.of_node = pdev->dev.of_node;210 thc63->bridge.funcs = &thc63_bridge_func;211 thc63->bridge.timings = &thc63->timings;212 213 drm_bridge_add(&thc63->bridge);214 215 return 0;216}217 218static void thc63_remove(struct platform_device *pdev)219{220 struct thc63_dev *thc63 = platform_get_drvdata(pdev);221 222 drm_bridge_remove(&thc63->bridge);223}224 225static const struct of_device_id thc63_match[] = {226 { .compatible = "thine,thc63lvd1024", },227 { },228};229MODULE_DEVICE_TABLE(of, thc63_match);230 231static struct platform_driver thc63_driver = {232 .probe = thc63_probe,233 .remove_new = thc63_remove,234 .driver = {235 .name = "thc63lvd1024",236 .of_match_table = thc63_match,237 },238};239module_platform_driver(thc63_driver);240 241MODULE_AUTHOR("Jacopo Mondi <jacopo@jmondi.org>");242MODULE_DESCRIPTION("Thine THC63LVD1024 LVDS decoder DRM bridge driver");243MODULE_LICENSE("GPL v2");244