Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Subject: Re: [PATCH v6 02/17] media: v4l2: async: Allow searching for asd of
 any type
To:     Mauro Carvalho Chehab <mchehab+samsung@kernel.org>,
        Steve Longerbeam <slongerbeam@gmail.com>
CC:     <linux-media@vger.kernel.org>,
        Mauro Carvalho Chehab <mchehab@kernel.org>,
        Sakari Ailus <sakari.ailus@linux.intel.com>,
        =?UTF-8?Q?Niklas_S=c3=b6derlund?= 
        <niklas.soderlund+renesas@ragnatech.se>,
        Hans Verkuil <hans.verkuil@cisco.com>,
        Sebastian Reichel <sre@kernel.org>,
        open list <linux-kernel@vger.kernel.org>
References: <1531175957-1973-1-git-send-email-steve_longerbeam@mentor.com>
 <1531175957-1973-3-git-send-email-steve_longerbeam@mentor.com>
 <20180924140604.23e2b56f@coco.lan>
From:   Steve Longerbeam <steve_longerbeam@mentor.com>
Message-ID: <a8ea673c-a519-81e8-35b1-9d4a224dcbf5@mentor.com>
Date:   Tue, 25 Sep 2018 14:04:21 -0700
User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101
 Thunderbird/52.9.1
MIME-Version: 1.0
In-Reply-To: <20180924140604.23e2b56f@coco.lan>
Content-Type: text/plain; charset="utf-8"; format=flowed
Content-Transfer-Encoding: 7bit
Content-Language: en-US
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Hi Mauro,


On 09/24/2018 10:06 AM, Mauro Carvalho Chehab wrote:
> Em Mon,  9 Jul 2018 15:39:02 -0700
> Steve Longerbeam <slongerbeam@gmail.com> escreveu:
>
>> Generalize v4l2_async_notifier_fwnode_has_async_subdev() to allow
>> searching for any type of async subdev, not just fwnodes. Rename to
>> v4l2_async_notifier_has_async_subdev() and pass it an asd pointer.
>>
>> Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>
>> ---
>> Changes since v5:
>> - none
>> Changes since v4:
>> - none
>> Changes since v3:
>> - removed TODO to support asd compare with CUSTOM match type in
>>    asd_equal().
>> Changes since v2:
>> - code optimization in asd_equal(), and remove unneeded braces,
>>    suggested by Sakari Ailus.
>> Changes since v1:
>> - none
>> ---
>>   drivers/media/v4l2-core/v4l2-async.c | 73 +++++++++++++++++++++---------------
>>   1 file changed, 43 insertions(+), 30 deletions(-)
>>
>> diff --git a/drivers/media/v4l2-core/v4l2-async.c b/drivers/media/v4l2-core/v4l2-async.c
>> index 2b08d03..0e7e529 100644
>> --- a/drivers/media/v4l2-core/v4l2-async.c
>> +++ b/drivers/media/v4l2-core/v4l2-async.c
>> @@ -124,6 +124,31 @@ static struct v4l2_async_subdev *v4l2_async_find_match(
>>   	return NULL;
>>   }
>>   
>> +/* Compare two asd's for equivalence */
> Please, on comments, instead of "asd" prefer to use what this 3 random
> letters mean, e. g.:
> 	asd -> asynchronous subdevice

Ok, I will change the comment to read:

/* Compare two async subdevice descriptors for equivalence */

>
>> +static bool asd_equal(struct v4l2_async_subdev *asd_x,
>> +		      struct v4l2_async_subdev *asd_y)
>> +{
>> +	if (asd_x->match_type != asd_y->match_type)
>> +		return false;
>> +
>> +	switch (asd_x->match_type) {
>> +	case V4L2_ASYNC_MATCH_DEVNAME:
>> +		return strcmp(asd_x->match.device_name,
>> +			      asd_y->match.device_name) == 0;
>> +	case V4L2_ASYNC_MATCH_I2C:
>> +		return asd_x->match.i2c.adapter_id ==
>> +			asd_y->match.i2c.adapter_id &&
>> +			asd_x->match.i2c.address ==
>> +			asd_y->match.i2c.address;
>> +	case V4L2_ASYNC_MATCH_FWNODE:
>> +		return asd_x->match.fwnode == asd_y->match.fwnode;
>> +	default:
>> +		break;
>> +	}
>> +
>> +	return false;
>> +}
>> +
>>   /* Find the sub-device notifier registered by a sub-device driver. */
>>   static struct v4l2_async_notifier *v4l2_async_find_subdev_notifier(
>>   	struct v4l2_subdev *sd)
>> @@ -308,29 +333,22 @@ static void v4l2_async_notifier_unbind_all_subdevs(
>>   	notifier->parent = NULL;
>>   }
>>   
>> -/* See if an fwnode can be found in a notifier's lists. */
>> -static bool __v4l2_async_notifier_fwnode_has_async_subdev(
>> -	struct v4l2_async_notifier *notifier, struct fwnode_handle *fwnode)
>> +/* See if an async sub-device can be found in a notifier's lists. */
>> +static bool __v4l2_async_notifier_has_async_subdev(
>> +	struct v4l2_async_notifier *notifier, struct v4l2_async_subdev *asd)
> This is a minor issue, but checkpatch complains (with reason)
> (with --strict) about the above:
>
> 	CHECK: Lines should not end with a '('
> 	#63: FILE: drivers/media/v4l2-core/v4l2-async.c:337:
> 	+static bool __v4l2_async_notifier_has_async_subdev(
>
> Better to declare it, instead, as:
>
> static bool
> __v4l2_async_notifier_has_async_subdev(struct v4l2_async_notifier *notifier,
> 				       struct v4l2_async_subdev *asd)
>
> Similar warnings appear on other places:
> CHECK: Lines should not end with a '('
> #102: FILE: drivers/media/v4l2-core/v4l2-async.c:362:
> +static bool v4l2_async_notifier_has_async_subdev(
>
> CHECK: Lines should not end with a '('
> #141: FILE: drivers/media/v4l2-core/v4l2-async.c:410:
> +			if (v4l2_async_notifier_has_async_subdev(

Will fix.

>
> Btw, Checkpatch also complains that the author's email is different
> than the SOB's one:
>
> WARNING: Missing Signed-off-by: line by nominal patch author 'Steve Longerbeam <slongerbeam@gmail.com>'
>
> (the some comes with Signed-off-by: Steve Longerbeam <steve_longerbeam@mentor.com>)
>
> I suspect that other patches on this series will suffer from the same issue.

Will fix when submitting v7.

> <snip>
>
>> @@ -392,12 +406,11 @@ static int __v4l2_async_notifier_register(struct v4l2_async_notifier *notifier)
>>   		case V4L2_ASYNC_MATCH_CUSTOM:
>>   		case V4L2_ASYNC_MATCH_DEVNAME:
>>   		case V4L2_ASYNC_MATCH_I2C:
>> -			break;
>>   		case V4L2_ASYNC_MATCH_FWNODE:
>> -			if (v4l2_async_notifier_fwnode_has_async_subdev(
>> -				    notifier, asd->match.fwnode, i)) {
>> +			if (v4l2_async_notifier_has_async_subdev(
>> +				    notifier, asd, i)) {
>>   				dev_err(dev,
>> -					"fwnode has already been registered or in notifier's subdev list\n");
>> +					"asd has already been registered or in notifier's subdev list\n");
> Please, never use "asd" on messages printed to the user. While someone
> may understand it while reading the source code, for a poor use,
> "asd" is just a random sequence of 3 characters.

I will change the message to read:

"subdev descriptor already listed in this or other notifiers".


Steve