panel-lvds.c
// SPDX-License-Identifier: GPL-2.0+
/*
* Generic LVDS panel driver
*
* Copyright (C) 2016 Laurent Pinchart
* Copyright (C) 2016 Renesas Electronics Corporation
*
* Contact: Laurent Pinchart (laurent.pinchart@ideasonboard.com)
*/
#include <linux/gpio/consumer.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
#include <video/display_timing.h>
#include <video/of_display_timing.h>
#include <video/videomode.h>
#include <drm/drm_crtc.h>
#include <drm/drm_of.h>
#include <drm/drm_panel.h>
struct panel_lvds {
struct drm_panel panel;
struct device *dev;
const char *label;
unsigned int width;
unsigned int height;
struct drm_display_mode dmode;
u32 bus_flags;
unsigned int bus_format;
struct regulator *supply;
struct gpio_desc *enable_gpio;
struct gpio_desc *reset_gpio;
enum drm_panel_orientation orientation;
};
static inline struct panel_lvds *to_panel_lvds(struct drm_panel *panel)
{
return container_of(panel, struct panel_lvds, panel);
}
static int panel_lvds_unprepare(struct drm_panel *panel)
{
struct panel_lvds *lvds = to_panel_lvds(panel);
if (lvds->enable_gpio)
gpiod_set_value_cansleep(lvds->enable_gpio, 0);
if (lvds->supply)
regulator_disable(lvds->supply);
return 0;
}
static int panel_lvds_prepare(struct drm_panel *panel)
{
struct panel_lvds *lvds = to_panel_lvds(panel);
if (lvds->supply) {
int err;
err = regulator_enable(lvds->supply);
if (err < 0) {
dev_err(lvds->dev, "failed to enable supply: %d\n",
err);
return err;
}
}
if (lvds->enable_gpio)
gpiod_set_value_cansleep(lvds->enable_gpio, 1);
return 0;
}
static int panel_lvds_get_modes(struct drm_panel *panel,
struct drm_connector *connector)
{
struct panel_lvds *lvds = to_panel_lvds(panel);
struct drm_display_mode *mode;
mode = drm_mode_duplicate(connector->dev, &lvds->dmode);
if (!mode)
return 0;
mode->type |= DRM_MODE_TYPE_DRIVER | DRM_MODE_TYPE_PREFERRED;
drm_mode_probed_add(connector, mode);
connector->display_info.width_mm = lvds->dmode.width_mm;
connector->display_info.height_mm = lvds->dmode.height_mm;
drm_display_info_set_bus_formats(&connector->display_info,
&lvds->bus_format, 1);
connector->display_info.bus_flags = lvds->bus_flags;
/*
* TODO: Remove once all drm drivers call
* drm_connector_set_orientation_from_panel()
*/
drm_connector_set_panel_orientation(connector, lvds->orientation);
return 1;
}
static enum drm_panel_orientation panel_lvds_get_orientation(struct drm_panel *panel)
{
struct panel_lvds *lvds = to_panel_lvds(panel);
return lvds->orientation;
}
static const struct drm_panel_funcs panel_lvds_funcs = {
.unprepare = panel_lvds_unprepare,
.prepare = panel_lvds_prepare,
.get_modes = panel_lvds_get_modes,
.get_orientation = panel_lvds_get_orientation,
};
static int panel_lvds_parse_dt(struct panel_lvds *lvds)
{
struct device_node *np = lvds->dev->of_node;
int ret;
ret = of_drm_get_panel_orientation(np, &lvds->orientation);
if (ret < 0) {
dev_err(lvds->dev, "%pOF: failed to get orientation %d\n", np, ret);
return ret;
}
ret = of_get_drm_panel_display_mode(np, &lvds->dmode, &lvds->bus_flags);
if (ret < 0) {
dev_err(lvds->dev, "%pOF: problems parsing panel-timing (%d)\n",
np, ret);
return ret;
}
of_property_read_string(np, "label", &lvds->label);
ret = drm_of_lvds_get_data_mapping(np);
if (ret < 0) {
dev_err(lvds->dev, "%pOF: invalid or missing %s DT property\n",
np, "data-mapping");
return ret;
}
lvds->bus_format = ret;
lvds->bus_flags |= of_property_read_bool(np, "data-mirror") ?
DRM_BUS_FLAG_DATA_LSB_TO_MSB :
DRM_BUS_FLAG_DATA_MSB_TO_LSB;
return 0;
}
static int panel_lvds_probe(struct platform_device *pdev)
{
struct panel_lvds *lvds;
int ret;
lvds = devm_kzalloc(&pdev->dev, sizeof(*lvds), GFP_KERNEL);
if (!lvds)
return -ENOMEM;
lvds->dev = &pdev->dev;
ret = panel_lvds_parse_dt(lvds);
if (ret < 0)
return ret;
lvds->supply = devm_regulator_get_optional(lvds->dev, "power");
if (IS_ERR(lvds->supply)) {
ret = PTR_ERR(lvds->supply);
if (ret != -ENODEV) {
if (ret != -EPROBE_DEFER)
dev_err(lvds->dev, "failed to request regulator: %d\n",
ret);
return ret;
}
lvds->supply = NULL;
}
/* Get GPIOs and backlight controller. */
lvds->enable_gpio = devm_gpiod_get_optional(lvds->dev, "enable",
GPIOD_OUT_LOW);
if (IS_ERR(lvds->enable_gpio)) {
ret = PTR_ERR(lvds->enable_gpio);
dev_err(lvds->dev, "failed to request %s GPIO: %d\n",
"enable", ret);
return ret;
}
lvds->reset_gpio = devm_gpiod_get_optional(lvds->dev, "reset",
GPIOD_OUT_HIGH);
if (IS_ERR(lvds->reset_gpio)) {
ret = PTR_ERR(lvds->reset_gpio);
dev_err(lvds->dev, "failed to request %s GPIO: %d\n",
"reset", ret);
return ret;
}
/*
* TODO: Handle all power supplies specified in the DT node in a generic
* way for panels that don't care about power supply ordering. LVDS
* panels that require a specific power sequence will need a dedicated
* driver.
*/
/* Register the panel. */
drm_panel_init(&lvds->panel, lvds->dev, &panel_lvds_funcs,
DRM_MODE_CONNECTOR_LVDS);
ret = drm_panel_of_backlight(&lvds->panel);
if (ret)
return ret;
drm_panel_add(&lvds->panel);
dev_set_drvdata(lvds->dev, lvds);
return 0;
}
static void panel_lvds_remove(struct platform_device *pdev)
{
struct panel_lvds *lvds = platform_get_drvdata(pdev);
drm_panel_remove(&lvds->panel);
drm_panel_disable(&lvds->panel);
}
static const struct of_device_id panel_lvds_of_table[] = {
{ .compatible = "panel-lvds", },
{ /* Sentinel */ },
};
MODULE_DEVICE_TABLE(of, panel_lvds_of_table);
static struct platform_driver panel_lvds_driver = {
.probe = panel_lvds_probe,
.remove_new = panel_lvds_remove,
.driver = {
.name = "panel-lvds",
.of_match_table = panel_lvds_of_table,
},
};
module_platform_driver(panel_lvds_driver);
MODULE_AUTHOR("Laurent Pinchart <laurent.pinchart@ideasonboard.com>");
MODULE_DESCRIPTION("LVDS Panel Driver");
MODULE_LICENSE("GPL");