Re: [PATCH 3/6] IIO:CORE add global list of registered IIO devices.

From: Jonathan Cameron
Date: Wed Oct 19 2011 - 09:46:05 EST


On 10/18/11 21:33, Jonathan Cameron wrote:
> On 10/18/11 19:25, Lars-Peter Clausen wrote:
>> On 10/18/2011 05:29 PM, Jonathan Cameron wrote:
>>> Needed for inkernel interfaces.
>>>
>>
>> The bus_type structure keeps a list of all devices registered on that bus, so
>> you should be able to use bus_for_each_dev and bus_find_device for iterating
>> over the iio devices.
> I hadn't realised that but don't think it will work anyway. There are several
> other things than iio_dev based devices that sit on our bus unfortunately.
> None are in these initial merges but they will turn up later.
> The most common are iio_triggers but there are also a few weird ones such
> as the event generator for the dummy driver and the sysfstrig control device.
> We could play some games to allow these to be identified, but it's going
> to be a mess. Probably easier to just maintain a second list as we are doing
> here. Interesting suggestion though. Thanks and feel free to point out if there
> is a simple way around the identification issue.
Actually looking into it this morning - this is trivial to do.
We can just check that the device_type is set appropriately before doing anything
else.

Thanks Lars-Peter your suggestion is should clean things up nicely.

New version coming up.
>>
>>> Signed-off-by: Jonathan Cameron <jic23@xxxxxxxxx>
>>> ---
>>> drivers/iio/iio.c | 9 +++++++++
>>> include/linux/iio/iio.h | 1 +
>>> 2 files changed, 10 insertions(+), 0 deletions(-)
>>>
>>> diff --git a/drivers/iio/iio.c b/drivers/iio/iio.c
>>> index 9e6acc1..246a093 100644
>>> --- a/drivers/iio/iio.c
>>> +++ b/drivers/iio/iio.c
>>> @@ -15,6 +15,9 @@
>>> #include <linux/iio/iio.h>
>>> #include <linux/iio/sysfs.h>
>>>
>>> +static DEFINE_MUTEX(iio_device_list_lock);
>>> +static LIST_HEAD(iio_device_list);
>>> +
>>> static DEFINE_IDA(iio_ida);
>>>
>>> static struct bus_type iio_bus_type = {
>>> @@ -91,6 +94,9 @@ static void iio_dev_release(struct device *device)
>>> {
>>> struct iio_dev *indio_dev = container_of(device, struct iio_dev, dev);
>>> iio_device_unregister_sysfs(indio_dev);
>>> + mutex_lock(&iio_device_list_lock);
>>> + list_del(&indio_dev->dev_list_entry);
>>> + mutex_unlock(&iio_device_list_lock);
>>> }
>>>
>>> static struct device_type iio_dev_type = {
>>> @@ -559,6 +565,9 @@ int iio_device_register(struct iio_dev *indio_dev)
>>> if (ret)
>>> goto error_free_sysfs;
>>>
>>> + mutex_lock(&iio_device_list_lock);
>>> + list_add(&indio_dev->dev_list_entry, &iio_device_list);
>>> + mutex_unlock(&iio_device_list_lock);
>>> return 0;
>>>
>>> error_free_sysfs:
>>> diff --git a/include/linux/iio/iio.h b/include/linux/iio/iio.h
>>> index beedc5c..f14e7dc 100644
>>> --- a/include/linux/iio/iio.h
>>> +++ b/include/linux/iio/iio.h
>>> @@ -192,6 +192,7 @@ struct iio_info {
>>> * @info: [DRIVER] callbacks and constant info from driver
>>> * @groups: [INTERN] attribute groups
>>> * @groupcounter: [INTERN] index of next attribute group
>>> + * @dev_list_entry: [INTERN] entry in global list of iio devices
>>> **/
>>> struct iio_dev {
>>> int id;
>>
>> --
>> To unsubscribe from this list: send the line "unsubscribe linux-iio" in
>> the body of a message to majordomo@xxxxxxxxxxxxxxx
>> More majordomo info at http://vger.kernel.org/majordomo-info.html
>>
>
> --
> To unsubscribe from this list: send the line "unsubscribe linux-iio" in
> the body of a message to majordomo@xxxxxxxxxxxxxxx
> More majordomo info at http://vger.kernel.org/majordomo-info.html
>

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/