[PATCH 2/2] [media]: mx2_camera: Fix regression caused by clock conversion

[Guennadi Liakhovetski]

Hi Fabio

On Fri, 5 Oct 2012, Fabio Estevam wrote:

> Since mx27 transitioned to the commmon clock framework in 3.5, the correct way
> to acquire the csi clock is to get csi_ahb and csi_per clocks separately.
> 
> By not doing so the camera sensor does not probe correctly:
> 
> soc-camera-pdrv soc-camera-pdrv.0: Probing soc-camera-pdrv.0
> mx2-camera mx2-camera.0: Camera driver attached to camera 0
> ov2640 0-0030: Product ID error fb:fb
> mx2-camera mx2-camera.0: Camera driver detached from camera 0
> mx2-camera mx2-camera.0: MX2 Camera (CSI) driver probed, clock frequency: 66500000
> 
> Adapt the mx2_camera driver to the new clock framework and make it functional
> again.

Do I understand it right, that since the driver is currently broken, it 
doesn't matter any more in which order these two patches get applied, so, 
we can push them via different trees - ARM and media?

Thanks
Guennadi

> 
> Signed-off-by: Fabio Estevam <fabio.estevam at freescale.com>
> ---
>  drivers/media/platform/soc_camera/mx2_camera.c |   42 ++++++++++++++++--------
>  1 file changed, 29 insertions(+), 13 deletions(-)
> 
> diff --git a/drivers/media/platform/soc_camera/mx2_camera.c b/drivers/media/platform/soc_camera/mx2_camera.c
> index 0c0dd74..2c67969 100644
> --- a/drivers/media/platform/soc_camera/mx2_camera.c
> +++ b/drivers/media/platform/soc_camera/mx2_camera.c
> @@ -272,8 +272,9 @@ struct mx2_camera_dev {
>  	struct device		*dev;
>  	struct soc_camera_host	soc_host;
>  	struct soc_camera_device *icd;
> -	struct clk		*clk_csi, *clk_emma_ahb, *clk_emma_ipg;
> -
> +	struct clk		*clk_emma_ahb, *clk_emma_ipg;
> +	struct clk		*clk_csi_ahb, *clk_csi_per;
> +
>  	unsigned int		irq_csi, irq_emma;
>  	void __iomem		*base_csi, *base_emma;
>  	unsigned long		base_dma;
> @@ -435,7 +436,8 @@ static void mx2_camera_deactivate(struct mx2_camera_dev *pcdev)
>  {
>  	unsigned long flags;
>  
> -	clk_disable_unprepare(pcdev->clk_csi);
> +	clk_disable_unprepare(pcdev->clk_csi_ahb);
> +	clk_disable_unprepare(pcdev->clk_csi_per);
>  	writel(0, pcdev->base_csi + CSICR1);
>  	if (cpu_is_mx27()) {
>  		writel(0, pcdev->base_emma + PRP_CNTL);
> @@ -463,7 +465,11 @@ static int mx2_camera_add_device(struct soc_camera_device *icd)
>  	if (pcdev->icd)
>  		return -EBUSY;
>  
> -	ret = clk_prepare_enable(pcdev->clk_csi);
> +	ret = clk_prepare_enable(pcdev->clk_csi_ahb);
> +	if (ret < 0)
> +		return ret;
> +
> +	ret = clk_prepare_enable(pcdev->clk_csi_per);
>  	if (ret < 0)
>  		return ret;
>  
> @@ -1736,13 +1742,21 @@ static int __devinit mx2_camera_probe(struct platform_device *pdev)
>  		goto exit;
>  	}
>  
> -	pcdev->clk_csi = clk_get(&pdev->dev, "ahb");
> -	if (IS_ERR(pcdev->clk_csi)) {
> -		dev_err(&pdev->dev, "Could not get csi clock\n");
> -		err = PTR_ERR(pcdev->clk_csi);
> +	pcdev->clk_csi_ahb = clk_get(&pdev->dev, "ahb");
> +	if (IS_ERR(pcdev->clk_csi_ahb)) {
> +		dev_err(&pdev->dev, "Could not get csi ahb clock\n");
> +		err = PTR_ERR(pcdev->clk_csi_ahb);
>  		goto exit_kfree;
>  	}
>  
> +	pcdev->clk_csi_per = clk_get(&pdev->dev, "per");
> +	if (IS_ERR(pcdev->clk_csi_per)) {
> +		dev_err(&pdev->dev, "Could not get csi per clock\n");
> +		err = PTR_ERR(pcdev->clk_csi_per);
> +		goto exit_kfree;
> +	}
> +
> +
>  	pcdev->res_csi = res_csi;
>  	pcdev->pdata = pdev->dev.platform_data;
>  	if (pcdev->pdata) {
> @@ -1750,12 +1764,12 @@ static int __devinit mx2_camera_probe(struct platform_device *pdev)
>  
>  		pcdev->platform_flags = pcdev->pdata->flags;
>  
> -		rate = clk_round_rate(pcdev->clk_csi, pcdev->pdata->clk * 2);
> +		rate = clk_round_rate(pcdev->clk_csi_per, pcdev->pdata->clk * 2);
>  		if (rate <= 0) {
>  			err = -ENODEV;
>  			goto exit_dma_free;
>  		}
> -		err = clk_set_rate(pcdev->clk_csi, rate);
> +		err = clk_set_rate(pcdev->clk_csi_per, rate);
>  		if (err < 0)
>  			goto exit_dma_free;
>  	}
> @@ -1827,7 +1841,7 @@ static int __devinit mx2_camera_probe(struct platform_device *pdev)
>  		goto exit_free_emma;
>  
>  	dev_info(&pdev->dev, "MX2 Camera (CSI) driver probed, clock frequency: %ld\n",
> -			clk_get_rate(pcdev->clk_csi));
> +			clk_get_rate(pcdev->clk_csi_per));
>  
>  	return 0;
>  
> @@ -1851,7 +1865,8 @@ exit_iounmap:
>  exit_release:
>  	release_mem_region(res_csi->start, resource_size(res_csi));
>  exit_dma_free:
> -	clk_put(pcdev->clk_csi);
> +	clk_put(pcdev->clk_csi_per);
> +	clk_put(pcdev->clk_csi_ahb);
>  exit_kfree:
>  	kfree(pcdev);
>  exit:
> @@ -1865,7 +1880,8 @@ static int __devexit mx2_camera_remove(struct platform_device *pdev)
>  			struct mx2_camera_dev, soc_host);
>  	struct resource *res;
>  
> -	clk_put(pcdev->clk_csi);
> +	clk_put(pcdev->clk_csi_per);
> +	clk_put(pcdev->clk_csi_ahb);
>  	if (cpu_is_mx25())
>  		free_irq(pcdev->irq_csi, pcdev);
>  	if (cpu_is_mx27())
> -- 
> 1.7.9.5
> 
> 

---
Guennadi Liakhovetski, Ph.D.
Freelance Open-Source Software Developer
http://www.open-technology.de/