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

[javier Martin]

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)


>>
>>> 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.



-- 
Javier Martin
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