[PATCH] ARM : i.MX27 : split code for allocation of ressources of camera and eMMA

[Gaëtan Carlier]

On 09/05/2012 11:11 AM, javier Martin wrote:
> On 5 September 2012 10:47, Gaëtan Carlier <gcembed at gmail.com> wrote:
>> On 09/05/2012 10:22 AM, javier Martin wrote:
>>>
>>> On 5 September 2012 09:37, Gaëtan Carlier <gcembed at gmail.com> wrote:
>>>>
>>>> Hi Javier,
>>>> This is because I will send a patch to add support of eMMA-PP. eMMA-PrP
>>>> is
>>>> not only used for soc-camera. It can also be used as stand-alone driver
>>>> and
>>>> now to be able to use eMMA-PrP module, IMX_HAVE_PLATFORM_MX2_CAMERA must
>>>> be
>>>> set.
>>>
>>>
>>> Do you mean the following stand-alone driver I submitted some time
>>> ago? Are you working on some improvements to it?
>>>
>>> http://git.kernel.org/?p=linux/kernel/git/torvalds/linux.git;a=blob;f=drivers/media/video/mx2_emmaprp.c;h=5f8a6f5b98f91c3af4e1bdbd06654e7b496d8d65;hb=HEAD
>>
>> yes
>>
>>>
>>> This driver can be used without applying your patch. Please take a
>>> look at the following patch which is pending to get merged in
>>> linux-media tree:
>>> https://patchwork.kernel.org/patch/1347921/
>>>
>>>
>>>> And if I follow this logic, I have to put declaration of eMMA-PP with
>>>> imx-fb
>>>> and eMMA-PP can only be enabled if IMX_HAVE_PLATFORM_IMX_FB.
>>>> Of course, eMMA-PrP is almost always used with soc-camera and eMMA-PP
>>>> with
>>>> LCDC (imx-fb) but eMMA can be used to do HW accelarated colorspace
>>>> conversion.
>>>
>>>
>>> Agree, there is already one driver supporting this feature.
>>>
>>>> It is not a problem for me to keep eMMA-PrP and mx2-camera together. It
>>>> was
>>>> just to have a more independant eMMA driver.
>>>
>>>
>>> I won't oppose to it, for me it is just aesthetic. However, you must
>>> do it properly without breaking existing boards such as Visstrim_M10.
>>
>> Ok, I missed your patch in mailing-list and I work with linux-next
>> (20120824) so I didn't know that my patch would break yours. Sorry.
>>
>>>
>>>> For the Visstrim_M10 board, I don't think that it is needed to set
>>>> IMX_HAVE_PLATFORM_MX2_EMMA because there is no reference to m2m-emmaprp
>>>> and
>>>> mx2-camera embeds handling of eMMA-PrP without using eMMA-PrP driver.
>>>
>>>
>>> The following patch was sent to the list in Agust the 20th and will be
>>> merged in the linux-media tree. This patch does reference m2m-emmaprp
>>> in Visstrim_M10
>>> https://patchwork.kernel.org/patch/1347921/
>>>
>>> So, please, since you have to fix the wrong chunk and have to send a
>>> v2 anyways I strongly encourage you to add the flag
>>> IMX_HAVE_PLATFORM_MX2_EMMA to Visstrim_M10. This way nothing will be
>>> broken no matter your patch gets merged after or before mine.
>>
>> What do you mean by "wrong chunk" ?
>
>
> Your patch does not apply cleanly to linux-next due to the following chunk:
>
>   diff --git a/arch/arm/mach-imx/devices-imx27.h
> b/arch/arm/mach-imx/devices-imx27.h
> index 0482293..d8eb4a0 100644
> --- a/arch/arm/mach-imx/devices-imx27.h
> +++ b/arch/arm/mach-imx/devices-imx27.h
> @@ -54,8 +54,10 @@ extern const struct imx_imx_uart_1irq_data
> imx27_imx_uart_data[];
>   extern const struct imx_mx2_camera_data imx27_mx2_camera_data;
>   #define imx27_add_mx2_camera(pdata)    \
>          imx_add_mx2_camera(&imx27_mx2_camera_data, pdata)
> +
> +extern const struct imx_mx2_emma_data imx27_mx2_emmaprp_data;
>   #define imx27_add_mx2_emmaprp()        \
> -       imx_add_mx2_emmaprp(&imx27_mx2_camera_data)
> +       imx_add_mx2_emmaprp(&imx27_mx2_emmaprp_data)
>
>
When I apply the patch (I save my mail and apply it), there is no 
conflict/reject. Tested on linux-next-20120824 and linux-next-20120905.
>>>
>>>> It seems that eMMA-PrP embeded in mx2camera handles more case than
>>>> stand-alone eMMA-PrP driver. Maybe eMMA-PrP driver needs some review to
>>>> handle all In/Out image formats ?
>>>
>>>
>>> eMMa-PrP is currently used in two drivers:
>>>
>>> 1.
>>> http://git.linuxtv.org/media_tree.git/blob/refs/heads/staging/for_v3.7:/drivers/media/platform/soc_camera/mx2_camera.c
>>> Where it is used as a substitute to a DMA that moves data between the
>>> CSI and RAM apart from providing more features like format conversion,
>>> etc... This is a soc_camera video capture driver.
>>>
>>> 2.
>>> http://git.linuxtv.org/media_tree.git/blob/refs/heads/staging/for_v3.7:/drivers/media/platform/mx2_emmaprp.c
>>> This is a stand-alone mem2mem v4l2 driver that can get YUYV 422 in the
>>> input and transform it to YUV 420. Of course, the driver can be
>>> extended to support more kinds of conversions.
>>>
>>> Regards.
>>>
>> Regards,
>> Gaëtan.
>
>
>