Hi Mario,
On 10 May 2016 at 01:51, Mario Six mario.six@gdsys.cc wrote:
Certain GPIO devices have the capability to switch their GPIOs into open-drain mode, that is, instead of actively driving the output (Push-pull output), the pin is connected to the collector (for a NPN transistor) or the drain (for a MOSFET) of a transistor, respectively. The pin then either forms an open circuit or a connection to ground, depending on the state of the transistor.
This patch adds functions to the GPIO uclass to switch GPIOs to open-drain mode on devices that support it.
Signed-off-by: Mario Six mario.six@gdsys.cc
v2:
- Added missing commit message
- Fixed error return value of dm_gpio_get_open_drain
- Fixed return value passing in dm_gpio_set_open_drain and added comment
- Added description of open-drain mode
drivers/gpio/gpio-uclass.c | 32 ++++++++++++++++++++++++++++++++ include/asm-generic/gpio.h | 34 ++++++++++++++++++++++++++++++++++ 2 files changed, 66 insertions(+)
Reviewed-by: Simon Glass sjg@chromium.org
Can you please do a follow-up patch to update the test/dm/gpio.c file to call these two methods? You'll need to update drivers/gpio/sandbox.c a little also.
Regards, Simon