Hi Pratyush,
On Fri, 29 May 2020 at 15:39, Pratyush Yadav p.yadav@ti.com wrote:
Hi,
This is a re-submission of Jean-Jacques' earlier work in October last year. It can be found at [0]. The goal is to facilitate porting drivers from the linux kernel. Most of the series will be about adding managed API to existing infrastructure (GPIO, reset, regmap (already submitted)).
This particular series is about GPIOs. It adds a managed API using the API as Linux. To make it 100% compatible with linux, there is a small deviation from u-boot's way of naming the gpio lists: the managed equivalent of gpio_request_by_name(..,"blabla-gpios", ...) is devm_gpiod_get_index(..., "blabla", ...)
Changes in v2:
The original series had a patch that checked for NULL pointers in the core GPIO functions. The checks were needed because of the addition of devm_gpiod_get_index_optional() which would return NULL when when no GPIO was assigned to the requested function. This is convenient for drivers that need to handle optional GPIOs.
Simon argued that those should be behind a Kconfig option because of code size concerns. He also argued against implicit return in the macro that checked for the optional GPIOs.
This submission removes the controversial patch so that base functionality can get unblocked.
We still need to take a stance on who is responsible for the NULL check: the driver or the GPIO core? Do we want to trust drivers to take care of the NULL checks, or do we want to distrust them and make sure they don't send us anything bogus in the GPIO core. For now the responsibility lies on the drivers by default. I will send a separate RFC of the NULL check patch and we can probably discuss the issue there.
[0] https://patchwork.ozlabs.org/project/uboot/cover/20191001115130.18886-1-jjhi...
Jean-Jacques Hiblot (2): drivers: gpio: Add a managed API to get a GPIO from the device-tree test: gpio: Add tests for the managed API
arch/sandbox/dts/test.dts | 10 ++++ drivers/gpio/gpio-uclass.c | 70 +++++++++++++++++++++++++ include/asm-generic/gpio.h | 47 +++++++++++++++++ test/dm/gpio.c | 102 +++++++++++++++++++++++++++++++++++++ 4 files changed, 229 insertions(+)
-- 2.26.2
The first question I have is why do you want to allocate the gpio_desc and return it? Doesn't the caller have a place for that in its private struct?
Regards, Simon