[PATCH 2/4] media: ov2640: add primary dt support
From: laurent.pinchart@ideasonboard.com (Laurent Pinchart)
Date: 2014-12-01 22:33:21
Also in:
linux-devicetree, linux-media
Hi Josh, Thank you for the patch. On Friday 28 November 2014 18:28:25 Josh Wu wrote:
quoted hunk ↗ jump to hunk
Add device tree support for ov2640. Cc: devicetree at vger.kernel.org Signed-off-by: Josh Wu <redacted> --- drivers/media/i2c/soc_camera/ov2640.c | 95 +++++++++++++++++++++++++++++--- 1 file changed, 89 insertions(+), 6 deletions(-)diff --git a/drivers/media/i2c/soc_camera/ov2640.cb/drivers/media/i2c/soc_camera/ov2640.c index 9ee910d..6506126 100644--- a/drivers/media/i2c/soc_camera/ov2640.c +++ b/drivers/media/i2c/soc_camera/ov2640.c@@ -18,6 +18,8 @@ #include <linux/i2c.h> #include <linux/slab.h> #include <linux/delay.h> +#include <linux/gpio.h> +#include <linux/of_gpio.h> #include <linux/v4l2-mediabus.h> #include <linux/videodev2.h>@@ -283,6 +285,10 @@ struct ov2640_priv { u32 cfmt_code; struct v4l2_clk *clk; const struct ov2640_win_size *win; + + struct soc_camera_subdev_desc ssdd_dt; + int reset_pin; + int pwr_down_pin; }; /*@@ -1047,6 +1053,70 @@ static struct v4l2_subdev_ops ov2640_subdev_ops = { .video = &ov2640_subdev_video_ops, }; +/* OF probe functions */ +static int ov2640_hw_power(struct device *dev, int on) +{ + struct i2c_client *client = to_i2c_client(dev); + struct ov2640_priv *priv = to_ov2640(client); + + dev_dbg(&client->dev, "%s: %s the camera\n", + __func__, on ? "ENABLE" : "DISABLE"); + + /* enable or disable the camera */ + gpio_direction_output(priv->pwr_down_pin, !on);
Isn't there a delay required to wake the chip up ?
+
+ return 0;
+}
+
+static int ov2640_hw_reset(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct ov2640_priv *priv = to_ov2640(client);
+If the reset GPIO isn't specified you should return immediately without waiting 120ms.
+ /* If enabled, give a reset impulse */ + gpio_direction_output(priv->reset_pin, 0); + msleep(20);
Please use usleep_range().
+ gpio_direction_output(priv->reset_pin, 1); + msleep(100);
Is the reset delay documented somewhere ? 100ms seems pretty large to me.
+
+ return 0;
+}
+
+static int ov2640_probe_dt(struct i2c_client *client,
+ struct ov2640_priv *priv)
+{
+ struct device_node *np = client->dev.of_node;
+ int ret;
+
+ priv->reset_pin = of_get_named_gpio(np, "reset-gpio", 0);
+ priv->pwr_down_pin = of_get_named_gpio(np, "power-down-gpio", 0);
+ if (!gpio_is_valid(priv->reset_pin) ||
+ !gpio_is_valid(priv->pwr_down_pin))
+ return -EINVAL;
+
+ ret = devm_gpio_request(&client->dev, priv->pwr_down_pin,
+ "power-down-pin");
+ if (ret < 0) {
+ dev_err(&client->dev, "request gpio pin %d failed\n",
+ priv->pwr_down_pin);
+ return ret;
+ }
+
+ ret = devm_gpio_request(&client->dev, priv->reset_pin, "reset_pin");
+ if (ret < 0) {
+ dev_err(&client->dev, "request gpio pin %d failed\n",
+ priv->reset_pin);
+ return ret;
+ }Please use the gpiod API with the devm_gpiod_get_index_optional() function, it will simply your code and take care about GPIO polarity automatically. Don't forget to specify the default state using the GPIOD_* flags.
quoted hunk ↗ jump to hunk
+ + /* Initialize the soc_camera_subdev_desc */ + priv->ssdd_dt.power = ov2640_hw_power; + priv->ssdd_dt.reset = ov2640_hw_reset; + client->dev.platform_data = &priv->ssdd_dt; + + return 0; +} + /* * i2c_driver functions */@@ -1058,12 +1128,6 @@ static int ov2640_probe(struct i2c_client *client, struct i2c_adapter *adapter = to_i2c_adapter(client->dev.parent); int ret; - if (!ssdd) { - dev_err(&adapter->dev, - "OV2640: Missing platform_data for driver\n"); - return -EINVAL; - } - if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA)) { dev_err(&adapter->dev, "OV2640: I2C-Adapter doesn't support SMBUS\n");@@ -1077,6 +1141,18 @@ static int ov2640_probe(struct i2c_client *client, return -ENOMEM; } + if (!ssdd) { + if (client->dev.of_node) { + ret = ov2640_probe_dt(client, priv); + if (ret) + return ret; + } else { + dev_err(&client->dev, + "Missing platform_data for driver\n"); + return -EINVAL; + } + } + v4l2_i2c_subdev_init(&priv->subdev, client, &ov2640_subdev_ops); v4l2_ctrl_handler_init(&priv->hdl, 2); v4l2_ctrl_new_std(&priv->hdl, &ov2640_ctrl_ops,@@ -1123,9 +1199,16 @@ static const struct i2c_device_id ov2640_id[] = { }; MODULE_DEVICE_TABLE(i2c, ov2640_id); +static const struct of_device_id ov2640_of_match[] = { + {.compatible = "omnivision,ov2640", }, + {}, +}; +MODULE_DEVICE_TABLE(of, ov2640_of_match); + static struct i2c_driver ov2640_i2c_driver = { .driver = { .name = "ov2640", + .of_match_table = of_match_ptr(ov2640_of_match), }, .probe = ov2640_probe, .remove = ov2640_remove,
-- Regards, Laurent Pinchart