Subject: [PATCH 2/3] media: atmel-isi: add runtime pm support

From: [email-masked] (Josh Wu)
Date: Fri, 6 Mar 2015 18:10:36 +0800

On 3/5/2015 6:36 PM, Laurent Pinchart wrote:
> Hi Josh,
>
> Thank you for the patch.
>
> On Thursday 05 March 2015 13:01:00 Josh Wu wrote:
>> The runtime pm resume/suspend will enable/disable pclk (ISI peripheral
>> clock).
>> And we need to call rumtime_pm_get/put_sync function to make pm
>> resume/suspend.
>>
>> Signed-off-by: Josh Wu <[email-masked]>
>> ---
>>
>>   drivers/media/platform/soc_camera/atmel-isi.c | 36 +++++++++++++++++++++---
>>   1 file changed, 32 insertions(+), 4 deletions(-)
>>
>> diff --git a/drivers/media/platform/soc_camera/atmel-isi.c
>> b/drivers/media/platform/soc_camera/atmel-isi.c index eb179e7..4a384f1
>> 100644
>> --- a/drivers/media/platform/soc_camera/atmel-isi.c
>> +++ b/drivers/media/platform/soc_camera/atmel-isi.c
>> @@ -20,6 +20,7 @@
>>   #include <linux/kernel.h>
>>   #include <linux/module.h>
>>   #include <linux/platform_device.h>
>> +#include <linux/pm_runtime.h>
>>   #include <linux/slab.h>
>>
>>   #include <media/atmel-isi.h>
>> @@ -386,9 +387,7 @@ static int start_streaming(struct vb2_queue *vq,
>> unsigned int count) struct atmel_isi *isi = ici->priv;
>>   	int ret;
>>
>> -	ret = clk_prepare_enable(isi->pclk);
>> -	if (ret)
>> -		return ret;
>> +	pm_runtime_get_sync(ici->v4l2_dev.dev);
>>
>>   	/* Reset ISI */
>>   	ret = atmel_isi_wait_status(isi, WAIT_ISI_RESET);
>> @@ -450,7 +449,7 @@ static void stop_streaming(struct vb2_queue *vq)
>>   	if (ret < 0)
>>   		dev_err(icd->parent, "Disable ISI timed out\n");
>>
>> -	clk_disable_unprepare(isi->pclk);
>> +	pm_runtime_put_sync(ici->v4l2_dev.dev);
> Is there a reason to use pm_runtime_put_sync() and not just pm_runtime_put() ?

right, for sure we can use pm_runtime_put() here.

Best Regards,
Josh Wu
>
>>   }
>>
>>   static struct vb2_ops isi_video_qops = {
>> @@ -1042,6 +1041,9 @@ static int atmel_isi_probe(struct platform_device
>> *pdev) soc_host->v4l2_dev.dev	= &pdev->dev;
>>   	soc_host->nr		= pdev->id;
>>
>> +	pm_suspend_ignore_children(&pdev->dev, true);
>> +	pm_runtime_enable(&pdev->dev);
>> +
>>   	if (isi->pdata.asd_sizes) {
>>   		soc_host->asd = isi->pdata.asd;
>>   		soc_host->asd_sizes = isi->pdata.asd_sizes;
>> @@ -1055,6 +1057,7 @@ static int atmel_isi_probe(struct platform_device
>> *pdev) return 0;
>>
>>   err_register_soc_camera_host:
>> +	pm_runtime_disable(&pdev->dev);
>>   err_req_irq:
>>   err_ioremap:
>>   	vb2_dma_contig_cleanup_ctx(isi->alloc_ctx);
>> @@ -1067,6 +1070,30 @@ err_alloc_ctx:
>>   	return ret;
>>   }
>>
>> +static int atmel_isi_runtime_suspend(struct device *dev)
>> +{
>> +	struct soc_camera_host *soc_host = to_soc_camera_host(dev);
>> +	struct atmel_isi *isi = container_of(soc_host,
>> +					struct atmel_isi, soc_host);
>> +
>> +	clk_disable_unprepare(isi->pclk);
>> +
>> +	return 0;
>> +}
>> +static int atmel_isi_runtime_resume(struct device *dev)
>> +{
>> +	struct soc_camera_host *soc_host = to_soc_camera_host(dev);
>> +	struct atmel_isi *isi = container_of(soc_host,
>> +					struct atmel_isi, soc_host);
>> +
>> +	return clk_prepare_enable(isi->pclk);
>> +}
>> +
>> +static const struct dev_pm_ops atmel_isi_dev_pm_ops = {
>> +	SET_RUNTIME_PM_OPS(atmel_isi_runtime_suspend,
>> +				atmel_isi_runtime_resume, NULL)
>> +};
>> +
>>   static const struct of_device_id atmel_isi_of_match[] = {
>>   	{ .compatible = "atmel,at91sam9g45-isi" },
>>   	{ }
>> @@ -1079,6 +1106,7 @@ static struct platform_driver atmel_isi_driver = {
>>   		.name = "atmel_isi",
>>   		.owner = THIS_MODULE,
>>   		.of_match_table = of_match_ptr(atmel_isi_of_match),
>> +		.pm	= &atmel_isi_dev_pm_ops,
>>   	},
>>   };