Em Sat, 13 Apr 2013 16:15:39 +0300 Antti Palosaari <crope@xxxxxx> escreveu: > On 04/13/2013 12:48 PM, Frank Schäfer wrote: > > Patch 1 removes the unneeded and broken gpio register caching code. > > Patch 2 adds the gpio register defintions for the em25xx/em276x/7x/8x > > and patch 3 finally adds a new helper function for gpio ports with separate > > registers for read and write access. > > > I have nothing to say directly about those patches - they looked good at > the quick check. But I wonder if you have any idea if it is possible to > use some existing Kernel GPIO functionality in order to provide standard > interface (interface like I2C). I did some work last summer in order to > use GPIOLIB and it is used between em28xx-dvb and cxd2820r for LNA > control. Anyhow, I was a little bit disappointed as GPIOLIB is disabled > by default and due to that there is macros to disable LNA when GPIOLIB > is not compiled. > I noticed recently there is some ongoing development for Kernel GPIO. I > haven't looked yet if it makes use of GPIO interface more common... I have conflicting opinions myself weather we should use gpiolib or not. I don't mind with the fact that GPIOLIB is disabled by default. If all media drivers start depending on it, distros will enable it to keep media support on it. I never took the time to take a look on what methods gpiolib provides. Maybe it will bring some benefits. I dunno. Just looking at the existing drivers (almost all has some sort of GPIO config), GPIO is just a single register bitmask read/write. Most drivers need already bitmask read/write operations. So, in principle, I can't foresee any code simplification by using a library. Also, from a very pragmatic view, changing (almost) all existing drivers to use gpiolib is a big effort. However, for that to happen, one question should be answered: what benefits would be obtained by using gpiolib? Regards, Mauro -- To unsubscribe from this list: send the line "unsubscribe linux-media" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
