On 2016-12-30 08:49, Linus Walleij wrote:

On Wed, Dec 14, 2016 at 6:41 PM, Peter Rosin [off-list ref] wrote:

quoted

On 2016-12-14 18:01, Sebastian Reichel wrote:

quoted

[of course I forgot to actually add gpio people, let's try again]

On Wed, Dec 14, 2016 at 05:59:21PM +0100, Sebastian Reichel wrote:

quoted

Hi,

On Wed, Dec 14, 2016 at 12:56:45AM +0100, Peter Rosin wrote:

quoted

If several parallel bq24735 chargers have their ac-detect gpios wired
together (or if only one of the parallel bq24735 chargers have its
ac-detect pin wired to a gpio, and the others are assumed to react the
same), then all driver instances need to check the same gpio. But the
gpio subsystem does not allow sharing gpios, so handle that locally.

Adding GPIO subsystem people to see if they can come up with
something in the gpiod API for this usecase.

Right, I don't like how my new code steps away from gpio descriptors.

The issue of shared gpiods have come up over and over again.
For example the messy regulator code needs this too.

It is better if we implement something like gpiod_get_shared()
in the gpiolib of these cases.

Just put a refcount in struct gpio_desc in drivers/gpio/gpiolib.h
for this case I guess?

I actually tried that, but ran into atomicy issues with the
FLAG_REQUESTED bit and gave up. Didn't really try all that hard
though, but I simply didn't feel comfortable with going near such
fundamental designs...

Cheers,
peda