Subject: [PATCH 3/3] media: atmel-isi: remove mck back compatiable code as we don't need it

From: [email-masked] (Josh Wu)
Date: Fri, 6 Mar 2015 18:13:51 +0800

On 3/5/2015 6:41 PM, Laurent Pinchart wrote:
> Hi Josh,
>
> Thank you for the patch.
>
> On Thursday 05 March 2015 13:01:01 Josh Wu wrote:
>> The master clock should handled by sensor itself.
> I like that :-)
>
>> Signed-off-by: Josh Wu <[email-masked]>
>> ---
>>
>>   drivers/media/platform/soc_camera/atmel-isi.c | 32 ------------------------
>>   1 file changed, 32 deletions(-)
>>
>> diff --git a/drivers/media/platform/soc_camera/atmel-isi.c
>> b/drivers/media/platform/soc_camera/atmel-isi.c index 4a384f1..50375ce
>> 100644
>> --- a/drivers/media/platform/soc_camera/atmel-isi.c
>> +++ b/drivers/media/platform/soc_camera/atmel-isi.c
>> @@ -83,8 +83,6 @@ struct atmel_isi {
>>   	struct completion		complete;
>>   	/* ISI peripherial clock */
>>   	struct clk			*pclk;
>> -	/* ISI_MCK, feed to camera sensor to generate pixel clock */
>> -	struct clk			*mck;
>>   	unsigned int			irq;
>>
>>   	struct isi_platform_data	pdata;
>> @@ -725,26 +723,12 @@ static void isi_camera_remove_device(struct
>> soc_camera_device *icd) /* Called with .host_lock held */
>>   static int isi_camera_clock_start(struct soc_camera_host *ici)
>>   {
>> -	struct atmel_isi *isi = ici->priv;
>> -	int ret;
>> -
>> -	if (!IS_ERR(isi->mck)) {
>> -		ret = clk_prepare_enable(isi->mck);
>> -		if (ret) {
>> -			return ret;
>> -		}
>> -	}
>> -
>>   	return 0;
> Would it make sense to make the clock_start and clock_stop operations optional
> in the soc-camera core ?
I agree. For those camera host which don't provide master clock for 
sensor, clock_start and clock_stop should be optional.

Hi, Guennadi

Do you agree with this?

Best Regards,
Josh Wu

>
>>   }
>>
>>   /* Called with .host_lock held */
>>   static void isi_camera_clock_stop(struct soc_camera_host *ici)
>>   {
>> -	struct atmel_isi *isi = ici->priv;
>> -
>> -	if (!IS_ERR(isi->mck))
>> -		clk_disable_unprepare(isi->mck);
>>   }
>>
>>   static unsigned int isi_camera_poll(struct file *file, poll_table *pt)
>> @@ -894,7 +878,6 @@ static int atmel_isi_probe_dt(struct atmel_isi *isi,
>>
>>   	/* Default settings for ISI */
>>   	isi->pdata.full_mode = 1;
>> -	isi->pdata.mck_hz = ISI_DEFAULT_MCLK_FREQ;
>>   	isi->pdata.frate = ISI_CFG1_FRATE_CAPTURE_ALL;
>>
>>   	np = of_graph_get_next_endpoint(np, NULL);
>> @@ -970,21 +953,6 @@ static int atmel_isi_probe(struct platform_device
>> *pdev) INIT_LIST_HEAD(&isi->video_buffer_list);
>>   	INIT_LIST_HEAD(&isi->dma_desc_head);
>>
>> -	/* ISI_MCK is the sensor master clock. It should be handled by the
>> -	 * sensor driver directly, as the ISI has no use for that clock. Make
>> -	 * the clock optional here while platforms transition to the correct
>> -	 * model.
>> -	 */
>> -	isi->mck = devm_clk_get(dev, "isi_mck");
>> -	if (!IS_ERR(isi->mck)) {
>> -		/* Set ISI_MCK's frequency, it should be faster than pixel
>> -		 * clock.
>> -		 */
>> -		ret = clk_set_rate(isi->mck, isi->pdata.mck_hz);
>> -		if (ret < 0)
>> -			return ret;
>> -	}
>> -
>>   	isi->p_fb_descriptors = dma_alloc_coherent(&pdev->dev,
>>   				sizeof(struct fbd) * MAX_BUFFER_NUM,
>>   				&isi->fb_descriptors_phys,