Hi Josh, Thank you for the patch. On Friday 28 November 2014 18:28:25 Josh Wu wrote: > Add device tree support for ov2640. > > Cc: devicetree@xxxxxxxxxxxxxxx > Signed-off-by: Josh Wu <josh.wu@xxxxxxxxx> > --- > drivers/media/i2c/soc_camera/ov2640.c | 95 +++++++++++++++++++++++++++++--- > 1 file changed, 89 insertions(+), 6 deletions(-) > > diff --git a/drivers/media/i2c/soc_camera/ov2640.c > b/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. > + > + /* 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 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html