[U-Boot] [PATCH v6 1/4] EXYNOS5: Add gpio pin numbering feature

Lukasz Majewski
2014-04-14T07:17:27Z

Hi Akshay,

I'm not Samsung tree maintainer, but by chance I've come across those
patches and...

First question - why have you omitted u-boot-samsung tree maintainer?
I've added Minkyu to CC.

Also in the cover letter you claim that this patch was "build tested"
for Exynos4 based boards. Why didn't you add at least one maintainer of
those boards to CC?

> +
> +/* A list of valid GPIO numbers for the asm-generic/gpio.h interface
> */ +enum exynos5_gpio_pin {
> + /* GPIO_PART1_STARTS */
> + EXYNOS5_GPIO_A00, /* 0 */
> + EXYNOS5_GPIO_A01,
> + EXYNOS5_GPIO_A02,
> + EXYNOS5_GPIO_A03,
> + EXYNOS5_GPIO_A04,

According to the patch description, you had a compilation error when
were adding the support for Exynos 5250 and 5420. Why you fix the
problem by rewriting the whole framework?

IN the patch 2/4 you have:

- gpio_cfg_pin(start + i, GPIO_FUNC(0x2));
- gpio_set_pull(start + i, GPIO_PULL_NONE);
- gpio_set_drv(start + i, GPIO_DRV_4X);
+ gpio_cfg_pin(start + i, S5P_GPIO_FUNC(0x2));
+ gpio_set_pull(start + i, S5P_GPIO_PULL_NONE);
+ gpio_set_drv(start + i, S5P_GPIO_DRV_4X);

What is the rationale to change the name to S5P_GPIO and not stick to
GPIO_FUNC? In which way gpios for Exynos5 are different than for
Exynos4? Cannot we finally reuse the Exynos 4 and 5 code?

With the same patch:

- case PERIPH_ID_UART1:
- bank = &gpio1->d0;
- start = 0;
+ start = EXYNOS5_GPIO_D00;

What is wrong with specifying the bank field?
Why your gpio command cannot use the bank approach?

And one more question: Is this work compliant with new driver model,
which will be accepted at the merge window after the v2014.04 release?

If not, then there is no point to review this code, since GPIO would
need to be adjusted to use this framework.

--
Best regards,

Lukasz Majewski

Samsung R&D Institute Poland (SRPOL) | Linux Platform Group