// SPDX-License-Identifier: GPL-2.0
/*
* THC63LVD1024 LVDS to parallel data DRM bridge driver.
*
* Copyright (C) 2018 Jacopo Mondi <[email protected]>
*/
#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_graph.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#include <drm/drm_bridge.h>
#include <drm/drm_panel.h>
enum thc63_ports {
THC63_LVDS_IN0,
THC63_LVDS_IN1,
THC63_RGB_OUT0,
THC63_RGB_OUT1,
};
struct thc63_dev {
struct device *dev;
struct regulator *vcc;
struct gpio_desc *pdwn;
struct gpio_desc *oe;
struct drm_bridge bridge;
struct drm_bridge *next;
struct drm_bridge_timings timings;
};
static inline struct thc63_dev *to_thc63(struct drm_bridge *bridge)
{
return container_of(bridge, struct thc63_dev, bridge);
}
static int thc63_attach(struct drm_bridge *bridge,
enum drm_bridge_attach_flags flags)
{
struct thc63_dev *thc63 = to_thc63(bridge);
return drm_bridge_attach(bridge->encoder, thc63->next, bridge, flags);
}
static enum drm_mode_status thc63_mode_valid(struct drm_bridge *bridge,
const struct drm_display_info *info,
const struct drm_display_mode *mode)
{
struct thc63_dev *thc63 = to_thc63(bridge);
unsigned int min_freq;
unsigned int max_freq;
/*
* The THC63LVD1024 pixel rate range is 8 to 135 MHz in all modes but
* dual-in, single-out where it is 40 to 150 MHz. As dual-in, dual-out
* isn't supported by the driver yet, simply derive the limits from the
* input mode.
*/
if (thc63->timings.dual_link) {
min_freq = 40000;
max_freq = 150000;
} else {
min_freq = 8000;
max_freq = 135000;
}
if (mode->clock < min_freq)
return MODE_CLOCK_LOW;
if (mode->clock > max_freq)
return MODE_CLOCK_HIGH;
return MODE_OK;
}
static void thc63_enable(struct drm_bridge *bridge)
{
struct thc63_dev *thc63 = to_thc63(bridge);
int ret;
ret = regulator_enable(thc63->vcc);
if (ret) {
dev_err(thc63->dev,
"Failed to enable regulator \"vcc\": %d\n", ret);
return;
}
gpiod_set_value(thc63->pdwn, 0);
gpiod_set_value(thc63->oe, 1);
}
static void thc63_disable(struct drm_bridge *bridge)
{
struct thc63_dev *thc63 = to_thc63(bridge);
int ret;
gpiod_set_value(thc63->oe, 0);
gpiod_set_value(thc63->pdwn, 1);
ret = regulator_disable(thc63->vcc);
if (ret)
dev_err(thc63->dev,
"Failed to disable regulator \"vcc\": %d\n", ret);
}
static const struct drm_bridge_funcs thc63_bridge_func = {
.attach = thc63_attach,
.mode_valid = thc63_mode_valid,
.enable = thc63_enable,
.disable = thc63_disable,
};
static int thc63_parse_dt(struct thc63_dev *thc63)
{
struct device_node *endpoint;
struct device_node *remote;
remote = of_graph_get_remote_node(thc63->dev->of_node,
THC63_RGB_OUT0, -1);
if (!remote) {
dev_err(thc63->dev, "No remote endpoint for port@%u\n",
THC63_RGB_OUT0);
return -ENODEV;
}
thc63->next = of_drm_find_bridge(remote);
of_node_put(remote);
if (!thc63->next)
return -EPROBE_DEFER;
endpoint = of_graph_get_endpoint_by_regs(thc63->dev->of_node,
THC63_LVDS_IN1, -1);
if (endpoint) {
remote = of_graph_get_remote_port_parent(endpoint);
of_node_put(endpoint);
if (remote) {
if (of_device_is_available(remote))
thc63->timings.dual_link = true;
of_node_put(remote);
}
}
dev_dbg(thc63->dev, "operating in %s-link mode\n",
thc63->timings.dual_link ? "dual" : "single");
return 0;
}
static int thc63_gpio_init(struct thc63_dev *thc63)
{
thc63->oe = devm_gpiod_get_optional(thc63->dev, "oe", GPIOD_OUT_LOW);
if (IS_ERR(thc63->oe)) {
dev_err(thc63->dev, "Unable to get \"oe-gpios\": %ld\n",
PTR_ERR(thc63->oe));
return PTR_ERR(thc63->oe);
}
thc63->pdwn = devm_gpiod_get_optional(thc63->dev, "powerdown",
GPIOD_OUT_HIGH);
if (IS_ERR(thc63->pdwn)) {
dev_err(thc63->dev, "Unable to get \"powerdown-gpios\": %ld\n",
PTR_ERR(thc63->pdwn));
return PTR_ERR(thc63->pdwn);
}
return 0;
}
static int thc63_probe(struct platform_device *pdev)
{
struct thc63_dev *thc63;
int ret;
thc63 = devm_kzalloc(&pdev->dev, sizeof(*thc63), GFP_KERNEL);
if (!thc63)
return -ENOMEM;
thc63->dev = &pdev->dev;
platform_set_drvdata(pdev, thc63);
thc63->vcc = devm_regulator_get(thc63->dev, "vcc");
if (IS_ERR(thc63->vcc)) {
if (PTR_ERR(thc63->vcc) == -EPROBE_DEFER)
return -EPROBE_DEFER;
dev_err(thc63->dev, "Unable to get \"vcc\" supply: %ld\n",
PTR_ERR(thc63->vcc));
return PTR_ERR(thc63->vcc);
}
ret = thc63_gpio_init(thc63);
if (ret)
return ret;
ret = thc63_parse_dt(thc63);
if (ret)
return ret;
thc63->bridge.driver_private = thc63;
thc63->bridge.of_node = pdev->dev.of_node;
thc63->bridge.funcs = &thc63_bridge_func;
thc63->bridge.timings = &thc63->timings;
drm_bridge_add(&thc63->bridge);
return 0;
}
static void thc63_remove(struct platform_device *pdev)
{
struct thc63_dev *thc63 = platform_get_drvdata(pdev);
drm_bridge_remove(&thc63->bridge);
}
static const struct of_device_id thc63_match[] = {
{ .compatible = "thine,thc63lvd1024", },
{ },
};
MODULE_DEVICE_TABLE(of, thc63_match);
static struct platform_driver thc63_driver = {
.probe = thc63_probe,
.remove_new = thc63_remove,
.driver = {
.name = "thc63lvd1024",
.of_match_table = thc63_match,
},
};
module_platform_driver(thc63_driver);
MODULE_AUTHOR("Jacopo Mondi <[email protected]>");
MODULE_DESCRIPTION("Thine THC63LVD1024 LVDS decoder DRM bridge driver");
MODULE_LICENSE("GPL v2");
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