Re: [PATCH v1 06/11] exynos4-is: Add support for v4l2-flash subdevs

[Jacek Anaszewski <j.anaszewski@samsung.com>]

Hi Sakari,

Thanks for the review.

On 03/22/2015 02:21 AM, Sakari Ailus wrote:
> Hi Jacek,
>
> Some comments below. Please also get an ack from Sylwester! :-)

No doubt about that :)

> On Fri, Mar 20, 2015 at 04:03:26PM +0100, Jacek Anaszewski wrote:
>> This patch adds support for external v4l2-flash devices.
>> The support includes parsing "flashes" DT property
>> and asynchronous subdevice registration.
>>
>> Signed-off-by: Jacek Anaszewski <j.anaszewski@samsung.com>
>> Acked-by: Kyungmin Park <kyungmin.park@samsung.com>
>> Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
>> ---
>>   drivers/media/platform/exynos4-is/media-dev.c |   36 +++++++++++++++++++++++--
>>   drivers/media/platform/exynos4-is/media-dev.h |   13 ++++++++-
>>   2 files changed, 46 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/media/platform/exynos4-is/media-dev.c b/drivers/media/platform/exynos4-is/media-dev.c
>> index f315ef9..8dd0e5d 100644
>> --- a/drivers/media/platform/exynos4-is/media-dev.c
>> +++ b/drivers/media/platform/exynos4-is/media-dev.c
>> @@ -451,6 +451,25 @@ rpm_put:
>>   	return ret;
>>   }
>>
>> +static void fimc_md_register_flash_entities(struct fimc_md *fmd)
>> +{
>> +	struct device_node *parent = fmd->pdev->dev.of_node;
>> +	struct device_node *np;
>> +	int i = 0;
>> +
>> +	do {
>> +		np = of_parse_phandle(parent, "flashes", i);
>> +		if (np) {
>
> if (!np)
> 	break;
>
> And you can remove checking np another time in the loop condition.

Thanks, this will be cleaner indeed.

>> +			fmd->flash[fmd->num_flashes].asd.match_type =
>> +							V4L2_ASYNC_MATCH_OF;
>> +			fmd->flash[fmd->num_flashes].asd.match.of.node = np;
>> +			fmd->num_flashes++;
>> +			fmd->async_subdevs[fmd->num_sensors + i] =
>> +						&fmd->flash[i].asd;
>
> Have all the sensors been already registered by this point?

Function fimc_md_register_sensor_entities is called before
this one.

>> +		}
>> +	} while (np && (++i < FIMC_MAX_FLASHES));
>
> How about instead:
>
> fmd->num_flashes < FIMC_MAX_FLASHES
>
> And drop i. Also move incrementing num_flashes as last in the if.

Dropping i will enforce referring to fmd->num_flashes 7 times
in this short fragment of code.
Maybe it would be better to use a pointer to it?
int *nf = &fmd=>num_flashes ?

>> +}
>> +
>>   static int __of_get_csis_id(struct device_node *np)
>>   {
>>   	u32 reg = 0;
>> @@ -1275,6 +1294,15 @@ static int subdev_notifier_bound(struct v4l2_async_notifier *notifier,
>>   	struct fimc_sensor_info *si = NULL;
>>   	int i;
>>
>> +	/* Register flash subdev if detected any */
>> +	for (i = 0; i < ARRAY_SIZE(fmd->flash); i++) {
>> +		if (fmd->flash[i].asd.match.of.node == subdev->dev->of_node) {
>> +			fmd->flash[i].subdev = subdev;
>> +			fmd->num_flashes++;
>> +			return 0;
>> +		}
>> +	}
>> +
>>   	/* Find platform data for this sensor subdev */
>>   	for (i = 0; i < ARRAY_SIZE(fmd->sensor); i++)
>>   		if (fmd->sensor[i].asd.match.of.node == subdev->dev->of_node)
>> @@ -1385,6 +1413,8 @@ static int fimc_md_probe(struct platform_device *pdev)
>>   		goto err_m_ent;
>>   	}
>>
>> +	fimc_md_register_flash_entities(fmd);
>> +
>>   	mutex_unlock(&fmd->media_dev.graph_mutex);
>>
>>   	ret = device_create_file(&pdev->dev, &dev_attr_subdev_conf_mode);
>> @@ -1401,12 +1431,14 @@ static int fimc_md_probe(struct platform_device *pdev)
>>   		goto err_attr;
>>   	}
>>
>> -	if (fmd->num_sensors > 0) {
>> +	if (fmd->num_sensors > 0 || fmd->num_flashes > 0) {
>>   		fmd->subdev_notifier.subdevs = fmd->async_subdevs;
>> -		fmd->subdev_notifier.num_subdevs = fmd->num_sensors;
>> +		fmd->subdev_notifier.num_subdevs = fmd->num_sensors +
>> +							fmd->num_flashes;
>>   		fmd->subdev_notifier.bound = subdev_notifier_bound;
>>   		fmd->subdev_notifier.complete = subdev_notifier_complete;
>>   		fmd->num_sensors = 0;
>> +		fmd->num_flashes = 0;
>>
>>   		ret = v4l2_async_notifier_register(&fmd->v4l2_dev,
>>   						&fmd->subdev_notifier);
>> diff --git a/drivers/media/platform/exynos4-is/media-dev.h b/drivers/media/platform/exynos4-is/media-dev.h
>> index 0321454..feff9c8 100644
>> --- a/drivers/media/platform/exynos4-is/media-dev.h
>> +++ b/drivers/media/platform/exynos4-is/media-dev.h
>> @@ -34,6 +34,8 @@
>>
>>   #define FIMC_MAX_SENSORS	4
>>   #define FIMC_MAX_CAMCLKS	2
>> +#define FIMC_MAX_FLASHES	2
>> +#define FIMC_MAX_ASYNC_SUBDEVS (FIMC_MAX_SENSORS + FIMC_MAX_FLASHES)
>>   #define DEFAULT_SENSOR_CLK_FREQ	24000000U
>>
>>   /* LCD/ISP Writeback clocks (PIXELASYNCMx) */
>> @@ -93,6 +95,11 @@ struct fimc_sensor_info {
>>   	struct fimc_dev *host;
>>   };
>>
>> +struct fimc_flash_info {
>> +	struct v4l2_subdev *subdev;
>> +	struct v4l2_async_subdev asd;
>> +};
>> +
>>   struct cam_clk {
>>   	struct clk_hw hw;
>>   	struct fimc_md *fmd;
>> @@ -104,6 +111,8 @@ struct cam_clk {
>>    * @csis: MIPI CSIS subdevs data
>>    * @sensor: array of registered sensor subdevs
>>    * @num_sensors: actual number of registered sensors
>> + * @flash: array of registered flash subdevs
>> + * @num_flashes: actual number of registered flashes
>>    * @camclk: external sensor clock information
>>    * @fimc: array of registered fimc devices
>>    * @fimc_is: fimc-is data structure
>> @@ -123,6 +132,8 @@ struct fimc_md {
>>   	struct fimc_csis_info csis[CSIS_MAX_ENTITIES];
>>   	struct fimc_sensor_info sensor[FIMC_MAX_SENSORS];
>>   	int num_sensors;
>> +	struct fimc_flash_info flash[FIMC_MAX_FLASHES];
>> +	int num_flashes;
>>   	struct fimc_camclk_info camclk[FIMC_MAX_CAMCLKS];
>>   	struct clk *wbclk[FIMC_MAX_WBCLKS];
>>   	struct fimc_lite *fimc_lite[FIMC_LITE_MAX_DEVS];
>> @@ -149,7 +160,7 @@ struct fimc_md {
>>   	} clk_provider;
>>
>>   	struct v4l2_async_notifier subdev_notifier;
>> -	struct v4l2_async_subdev *async_subdevs[FIMC_MAX_SENSORS];
>> +	struct v4l2_async_subdev *async_subdevs[FIMC_MAX_ASYNC_SUBDEVS];
>>
>>   	bool user_subdev_api;
>>   	spinlock_t slock;
>


-- 
Best Regards,
Jacek Anaszewski