[v3][PATCH 4/5] media: ov2640: add a master clock for sensor

[Laurent Pinchart]

Hi Josh,

Thank you for the patch.

On Thursday 11 December 2014 15:35:38 Josh Wu wrote:
> The master clock (xvclk) is mandatory. It's a common clock framework clock.
> It can make sensor output a pixel clock to the camera interface.
> 
> Cc: devicetree at vger.kernel.org
> Signed-off-by: Josh Wu <josh.wu at atmel.com>

Acked-by: Laurent Pinchart <laurent.pinchart at ideasonboard.com>

> ---
> v2 -> v3:
>   1. should return PTR_ERR().
> 
> v1 -> v2:
>   1. change the clock's name.
>   2. Make the clock is mandatory.
> 
>  drivers/media/i2c/soc_camera/ov2640.c | 23 ++++++++++++++++++++++-
>  1 file changed, 22 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/media/i2c/soc_camera/ov2640.c
> b/drivers/media/i2c/soc_camera/ov2640.c index e0bcf5b..055702c 100644
> --- a/drivers/media/i2c/soc_camera/ov2640.c
> +++ b/drivers/media/i2c/soc_camera/ov2640.c
> @@ -13,6 +13,7 @@
>   * published by the Free Software Foundation.
>   */
> 
> +#include <linux/clk.h>
>  #include <linux/init.h>
>  #include <linux/module.h>
>  #include <linux/i2c.h>
> @@ -31,6 +32,7 @@
> 
>  #define VAL_SET(x, mask, rshift, lshift)  \
>  		((((x) >> rshift) & mask) << lshift)
> +
>  /*
>   * DSP registers
>   * register offset for BANK_SEL == BANK_SEL_DSP
> @@ -284,6 +286,7 @@ struct ov2640_priv {
>  	struct v4l2_ctrl_handler	hdl;
>  	u32	cfmt_code;
>  	struct v4l2_clk			*clk;
> +	struct clk			*master_clk;
>  	const struct ov2640_win_size	*win;
> 
>  	struct soc_camera_subdev_desc	ssdd_dt;
> @@ -746,6 +749,7 @@ static int ov2640_s_power(struct v4l2_subdev *sd, int
> on) struct soc_camera_subdev_desc *ssdd = soc_camera_i2c_to_desc(client);
> struct ov2640_priv *priv = to_ov2640(client);
>  	struct v4l2_clk *clk;
> +	int ret;
> 
>  	if (!priv->clk) {
>  		clk = v4l2_clk_get(&client->dev, "mclk");
> @@ -755,7 +759,20 @@ static int ov2640_s_power(struct v4l2_subdev *sd, int
> on) priv->clk = clk;
>  	}
> 
> -	return soc_camera_set_power(&client->dev, ssdd, priv->clk, on);
> +	if (on) {
> +		ret = clk_prepare_enable(priv->master_clk);
> +		if (ret)
> +			return ret;
> +	} else {
> +		clk_disable_unprepare(priv->master_clk);
> +	}
> +
> +	ret = soc_camera_set_power(&client->dev, ssdd, priv->clk, on);
> +
> +	if (ret && on)
> +		clk_disable_unprepare(priv->master_clk);
> +
> +	return ret;
>  }
> 
>  /* Select the nearest higher resolution for capture */
> @@ -1145,6 +1162,10 @@ static int ov2640_probe(struct i2c_client *client,
>  			return ret;
>  	}
> 
> +	priv->master_clk = devm_clk_get(&client->dev, "xvclk");
> +	if (IS_ERR(priv->master_clk))
> +		return PTR_ERR(priv->master_clk);
> +
>  	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,

-- 
Regards,

Laurent Pinchart