Quelle  ti-tdp158.c   Sprache: C

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright 2024 Freebox SAS
 */

#include <linux/gpio/consumer.h>
#include <linux/i2c.h>

#include <drm/drm_atomic_helper.h>
#include <drm/drm_bridge.h>

struct tdp158 {
 struct drm_bridge bridge;
 struct drm_bridge *next;
 struct gpio_desc *enable; // Operation Enable - pin 36
 struct regulator *vcc; // 3.3V
 struct regulator *vdd; // 1.1V
 struct device *dev;
};

static void tdp158_enable(struct drm_bridge *bridge,
     struct drm_atomic_state *state)
{
 int err;
 struct tdp158 *tdp158 = bridge->driver_private;

 err = regulator_enable(tdp158->vcc);
 if (err)
  dev_err(tdp158->dev, "failed to enable vcc: %d", err);

 err = regulator_enable(tdp158->vdd);
 if (err)
  dev_err(tdp158->dev, "failed to enable vdd: %d", err);

 gpiod_set_value_cansleep(tdp158->enable, 1);
}

static void tdp158_disable(struct drm_bridge *bridge,
      struct drm_atomic_state *state)
{
 struct tdp158 *tdp158 = bridge->driver_private;

 gpiod_set_value_cansleep(tdp158->enable, 0);
 regulator_disable(tdp158->vdd);
 regulator_disable(tdp158->vcc);
}

static int tdp158_attach(struct drm_bridge *bridge,
    struct drm_encoder *encoder,
    enum drm_bridge_attach_flags flags)
{
 struct tdp158 *tdp158 = bridge->driver_private;

 return drm_bridge_attach(encoder, tdp158->next, bridge, flags);
}

static const struct drm_bridge_funcs tdp158_bridge_funcs = {
 .attach = tdp158_attach,
 .atomic_enable = tdp158_enable,
 .atomic_disable = tdp158_disable,
 .atomic_duplicate_state = drm_atomic_helper_bridge_duplicate_state,
 .atomic_destroy_state = drm_atomic_helper_bridge_destroy_state,
 .atomic_reset = drm_atomic_helper_bridge_reset,
};

static int tdp158_probe(struct i2c_client *client)
{
 struct tdp158 *tdp158;
 struct device *dev = &client->dev;

 tdp158 = devm_drm_bridge_alloc(dev, struct tdp158, bridge,
           &tdp158_bridge_funcs);
 if (IS_ERR(tdp158))
  return PTR_ERR(tdp158);

 tdp158->next = devm_drm_of_get_bridge(dev, dev->of_node, 1, 0);
 if (IS_ERR(tdp158->next))
  return dev_err_probe(dev, PTR_ERR(tdp158->next), "missing bridge");

 tdp158->vcc = devm_regulator_get(dev, "vcc");
 if (IS_ERR(tdp158->vcc))
  return dev_err_probe(dev, PTR_ERR(tdp158->vcc), "vcc");

 tdp158->vdd = devm_regulator_get(dev, "vdd");
 if (IS_ERR(tdp158->vdd))
  return dev_err_probe(dev, PTR_ERR(tdp158->vdd), "vdd");

 tdp158->enable = devm_gpiod_get_optional(dev, "enable", GPIOD_OUT_LOW);
 if (IS_ERR(tdp158->enable))
  return dev_err_probe(dev, PTR_ERR(tdp158->enable), "enable");

 tdp158->bridge.of_node = dev->of_node;
 tdp158->bridge.driver_private = tdp158;
 tdp158->dev = dev;

 return devm_drm_bridge_add(dev, &tdp158->bridge);
}

static const struct of_device_id tdp158_match_table[] = {
 { .compatible = "ti,tdp158" },
 { }
};
MODULE_DEVICE_TABLE(of, tdp158_match_table);

static struct i2c_driver tdp158_driver = {
 .probe = tdp158_probe,
 .driver = {
  .name = "tdp158",
  .of_match_table = tdp158_match_table,
 },
};
module_i2c_driver(tdp158_driver);

MODULE_DESCRIPTION("TI TDP158 driver");
MODULE_LICENSE("GPL");