Re: [PATCH] cx25840: Declare MODULE_FIRMWARE usage

[Tim Gardner <tim.gardner@canonical.com>]

On 07/28/2012 10:52 AM, Andy Walls wrote:
> On Fri, 2012-07-27 at 06:06 -0600, Tim Gardner wrote:
>> On 07/26/2012 03:59 PM, Andy Walls wrote:
>>> On Thu, 2012-07-26 at 10:44 -0600, Tim Gardner wrote:
>>>> Cc: Mauro Carvalho Chehab <mchehab@infradead.org>
>>>> Cc: linux-media@vger.kernel.org
>>>> Signed-off-by: Tim Gardner <tim.gardner@canonical.com>
>>>> ---
>>>>    drivers/media/video/cx25840/cx25840-firmware.c |   15 ++++++++++++---
>>>>    1 file changed, 12 insertions(+), 3 deletions(-)
>>>>
>>>> diff --git a/drivers/media/video/cx25840/cx25840-firmware.c b/drivers/media/video/cx25840/cx25840-firmware.c
>>>> index 8150200..b3169f9 100644
>>>> --- a/drivers/media/video/cx25840/cx25840-firmware.c
>>>> +++ b/drivers/media/video/cx25840/cx25840-firmware.c
>>>> @@ -61,6 +61,10 @@ static void end_fw_load(struct i2c_client *client)
>>>>    	cx25840_write(client, 0x803, 0x03);
>>>>    }
>>>>
>>>> +#define CX2388x_FIRMWARE "v4l-cx23885-avcore-01.fw"
>>>> +#define CX231xx_FIRMWARE "v4l-cx231xx-avcore-01.fw"
>>>> +#define CX25840_FIRMWARE "v4l-cx25840.fw"
>>>> +
>>>>    static const char *get_fw_name(struct i2c_client *client)
>>>>    {
>>>>    	struct cx25840_state *state = to_state(i2c_get_clientdata(client));
>>>> @@ -68,10 +72,10 @@ static const char *get_fw_name(struct i2c_client *client)
>>>>    	if (firmware[0])
>>>>    		return firmware;
>>>>    	if (is_cx2388x(state))
>>>> -		return "v4l-cx23885-avcore-01.fw";
>>>> +		return CX2388x_FIRMWARE;
>>>>    	if (is_cx231xx(state))
>>>> -		return "v4l-cx231xx-avcore-01.fw";
>>>> -	return "v4l-cx25840.fw";
>>>> +		return CX231xx_FIRMWARE;
>>>> +	return CX25840_FIRMWARE;
>>>>    }
>>>>
>>>>    static int check_fw_load(struct i2c_client *client, int size)
>>>> @@ -164,3 +168,8 @@ int cx25840_loadfw(struct i2c_client *client)
>>>>
>>>>    	return check_fw_load(client, size);
>>>>    }
>>>> +
>>>> +MODULE_FIRMWARE(CX2388x_FIRMWARE);
>>>> +MODULE_FIRMWARE(CX231xx_FIRMWARE);
>>>> +MODULE_FIRMWARE(CX25840_FIRMWARE);
>>>> +
>>>
>>> How will the firmware attribute in the .module_info section be used?
>>>
>>> For any one model of TV capture device, the cx25840 only needs one of
>>> the above firmware files.  The others need not exist.
>>>
>>> I would not want anything in user or kernel space to refuse to load the
>>> module just because all 3 firmware files are not present.
>>>
>>> Regards,
>>> Andy
>>>
>>
>> The MODULE_FIRMWARE macro is purely informational. Declaring the
>> firmware files that the driver _might_ use helps me pare down the
>> external firmware package to just those files that I know it must have.
>
> Would it help if the MODULE_FIRMWARE text was more descriptive, e.g.:
>
> MODULE_FIRMWARE(CX25840_FIRMWARE " CX25840/1/2/3 chips only");
> MODULE_FIRMWARE(CX231xx_FIRMWARE " CX23100/1/2 chips only");
> MODULE_FIRMWARE(CX2388x_FIRMWARE " CX23885/7/8 chips only");
>
> Similarly for ivtv:
>
> MODULE_FIRMWARE(CX2341X_FIRM_ENC_FILENAME);
> MODULE_FIRMWARE(CX2341X_FIRM_DEC_FILENAME " PVR-350 only");
> MODULE_FIRMWARE(IVTV_DECODE_INIT_MPEG_FILENAME " PVR-350 only");
>
> and cx18:
>
> MODULE_FIRMWARE(FWFILE); /* v4l-cx23418-dig.fw */
> MODULE_FIRMWARE(CX18_CPU_FIRMWARE);
> MODULE_FIRMWARE(CX18_APU_FIRMWARE);
> MODULE_FIRMWARE(XC2028_DEFAULT_FIRMWARE " Non-HVR-1600 cards");
> MODULE_FIRMWARE(FWFILE " Yuan MPC-718 only");
>
> or would that confuse some userspace tools?
>

Yeah, I think it would confuse any tools that assume the firmware string 
emitted by modinfo is a literal filename.

rtg
-- 
Tim Gardner tim.gardner@canonical.com