[U-Boot] [PATCH v9 12/12] dm: exynos: gpio: Convert to driver model

[Przemyslaw Marczak <p.marczak@samsung.com>]

Hello Simon,

On 10/15/2014 10:38 AM, Simon Glass wrote:
> Convert the exynos GPIO driver to driver model. This implements the generic
> GPIO interface but not the extra Exynos-specific functions.
>
> Signed-off-by: Simon Glass <sjg@chromium.org>
> ---
>
> Changes in v9:
> - Add missing compatible strings from exynos_gpio_ids[]
>
> Changes in v8:
> - Enable driver model for smdkc100 and s5p_goni separately
>
> Changes in v7:
> - Bring in patches from the SPI series to move post-reloc DM init earlier
>
> Changes in v6: None
> Changes in v5:
> - Remove RFC label now that build errors are fixed
> - Tidy up and update cover letter message
> - Avoid reordering functions
>
> Changes in v4:
> - Add patches for exynos GPIO support
>
>   drivers/gpio/s5p_gpio.c         | 424 +++++++++++++++++++++++++++-------------
>   include/configs/exynos-common.h |   4 +
>   include/configs/s5p_goni.h      |   3 +
>   include/configs/smdkc100.h      |   3 +
>   4 files changed, 298 insertions(+), 136 deletions(-)
>
> diff --git a/drivers/gpio/s5p_gpio.c b/drivers/gpio/s5p_gpio.c
> index 99f2dd8..13d74eb 100644
> --- a/drivers/gpio/s5p_gpio.c
> +++ b/drivers/gpio/s5p_gpio.c
> @@ -6,8 +6,15 @@
>    */
>

..snip..

> +/**
> + * We have a top-level GPIO device with no actual GPIOs. It has a child
> + * device for each Exynos GPIO bank.
> + */
> +static int gpio_exynos_bind(struct udevice *parent)
> +{
> +	struct exynos_gpio_platdata *plat = parent->platdata;
> +	struct s5p_gpio_bank *bank, *base;
> +	const void *blob = gd->fdt_blob;
> +	int node;
> +
> +	/* If this is a child device, there is nothing to do here */
> +	if (plat)
> +		return 0;
> +
> +	base = (struct s5p_gpio_bank *)fdtdec_get_addr(gd->fdt_blob,
> +						   parent->of_offset, "reg");
> +	for (node = fdt_first_subnode(blob, parent->of_offset), bank = base;
> +	     node > 0;
> +	     node = fdt_next_subnode(blob, node), bank++) {

Here (bank++) you assume, that order of subnodes of each pinctrl is the 
same like in dts file - as I wrote in comment to patch 04 - it isn't.

> +		struct exynos_gpio_platdata *plat;
> +		struct udevice *dev;
> +		fdt_addr_t reg;
> +		int ret;
> +
> +		if (!fdtdec_get_bool(blob, node, "gpio-controller"))
> +			continue;
> +		plat = calloc(1, sizeof(*plat));
> +		if (!plat)
> +			return -ENOMEM;

Some parts of GPIO banks, for which "reg" can be found are prober.

> +		reg = fdtdec_get_addr(blob, node, "reg");
> +		if (reg != FDT_ADDR_T_NONE)
> +			bank = (struct s5p_gpio_bank *)((ulong)base + reg);
> +		plat->bank = bank;
> +		plat->bank_name = fdt_get_name(blob, node, NULL);
> +		debug("dev at %p: %s\n", bank, plat->bank_name);
> +
> +		ret = device_bind(parent, parent->driver,
> +					plat->bank_name, plat, -1, &dev);
> +		if (ret)
> +			return ret;
> +		dev->of_offset = parent->of_offset;
> +	}
> +
> +	return 0;
> +}
> +
> +static const struct udevice_id exynos_gpio_ids[] = {
> +	{ .compatible = "samsung,s5pc100-pinctrl" },
> +	{ .compatible = "samsung,s5pc110-pinctrl" },
> +	{ .compatible = "samsung,exynos4210-pinctrl" },
> +	{ .compatible = "samsung,exynos4x12-pinctrl" },
> +	{ .compatible = "samsung,exynos5250-pinctrl" },
> +	{ .compatible = "samsung,exynos5420-pinctrl" },
> +	{ }

... snip ...

And this is not the end of issues:)

Unfortunately Exynos4xxx has a gaps in GPIO bank address space, and the 
big gpio enum lists includes that here:
arch/arm/include/asm/arch-exynos/gpio.h

This works for Exynos5, because it's enum list is linear.

And the driver gpio-uclass.c - assumes that the gpio numbers are linear.
When I removed the gaps in enum for 4x12 -then gpio is mapped good.

And after remove the enum gaps, it also requires fitting the gpios in 
dts files, e.g. cd-gpio, pwr-gpios for sdhci host.

Sorry for such late reply in v9 but, before it seems working fine - I 
didn't try to check the sd card before.

I hope that after that fixes, everything will work fine:)

Best Regards,
-- 
Przemyslaw Marczak
Samsung R&D Institute Poland
Samsung Electronics
p.marczak at samsung.com