[PATCH 1/2] pinctrl: at91: allow disabled gpio controllers

[Jean-Christophe PLAGNIOL-VILLARD]

On 17:49 Fri 28 Nov     , Ludovic Desroches wrote:
> This patch allows to have gpio controller with status set to disabled.
> 
> gpio_banks represents all the gpio banks available on the device whereas
> nbanks represents the gpio banks used. Having a disabled gpio controller
> involves that nbanks value is lower than gpio_banks and that some
> pointers in the gpio_chips array are NULL. This patch deals with these
> specific cases.
> 
> Signed-off-by: Ludovic Desroches <ludovic.desroches at atmel.com>
> ---
> 
> Hi,
> 
> Without this patch, pinctrl is broken on sama5d4 because pinctrl-at91 doesn't
> support unused gpio bank.

the problem is different

The current code does support this partially

but need to have few by using gpio_banks for the pinctrl part instead of
info->banks
as we already known the last enabled bank

> 
> 
>  drivers/pinctrl/pinctrl-at91.c | 30 ++++++++++++++++++------------
>  1 file changed, 18 insertions(+), 12 deletions(-)
> 
> diff --git a/drivers/pinctrl/pinctrl-at91.c b/drivers/pinctrl/pinctrl-at91.c
> index 94643bb..95ae122 100644
> --- a/drivers/pinctrl/pinctrl-at91.c
> +++ b/drivers/pinctrl/pinctrl-at91.c
> @@ -981,7 +981,8 @@ static void at91_pinctrl_child_count(struct at91_pinctrl *info,
>  
>  	for_each_child_of_node(np, child) {
>  		if (of_device_is_compatible(child, gpio_compat)) {
> -			info->nbanks++;
> +			if (of_device_is_available(child))
> +				info->nbanks++;
>  		} else {
>  			info->nfunctions++;
>  			info->ngroups += of_get_child_count(child);
> @@ -1003,11 +1004,11 @@ static int at91_pinctrl_mux_mask(struct at91_pinctrl *info,
>  	}
>  
>  	size /= sizeof(*list);
> -	if (!size || size % info->nbanks) {
> +	if (!size || size % gpio_banks) {
>  		dev_err(info->dev, "wrong mux mask array should be by %d\n", info->nbanks);
>  		return -EINVAL;
>  	}
> -	info->nmux = size / info->nbanks;
> +	info->nmux = size / gpio_banks;
>  
>  	info->mux_mask = devm_kzalloc(info->dev, sizeof(u32) * size, GFP_KERNEL);
>  	if (!info->mux_mask) {
> @@ -1185,7 +1186,7 @@ static int at91_pinctrl_probe(struct platform_device *pdev)
>  {
>  	struct at91_pinctrl *info;
>  	struct pinctrl_pin_desc *pdesc;
> -	int ret, i, j, k;
> +	int ret, i, j, k, ngpio_chips_enabled = 0;
>  
>  	info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
>  	if (!info)
> @@ -1200,12 +1201,14 @@ static int at91_pinctrl_probe(struct platform_device *pdev)
>  	 * to obtain references to the struct gpio_chip * for them, and we
>  	 * need this to proceed.
>  	 */
> -	for (i = 0; i < info->nbanks; i++) {
> -		if (!gpio_chips[i]) {
> -			dev_warn(&pdev->dev, "GPIO chip %d not registered yet\n", i);
> -			devm_kfree(&pdev->dev, info);
> -			return -EPROBE_DEFER;
> -		}
> +	for (i = 0; i < gpio_banks; i++) {
> +		if (gpio_chips[i])
> +			ngpio_chips_enabled++;
> +	}
> +	if (ngpio_chips_enabled < info->nbanks) {
> +		dev_warn(&pdev->dev, "All GPIO chips are not registered yet\n");
> +		devm_kfree(&pdev->dev, info);
> +		return -EPROBE_DEFER;
>  	}
>  
>  	at91_pinctrl_desc.name = dev_name(&pdev->dev);
> @@ -1234,8 +1237,9 @@ static int at91_pinctrl_probe(struct platform_device *pdev)
>  	}
>  
>  	/* We will handle a range of GPIO pins */
> -	for (i = 0; i < info->nbanks; i++)
> -		pinctrl_add_gpio_range(info->pctl, &gpio_chips[i]->range);
> +	for (i = 0; i < gpio_banks; i++)
> +		if (gpio_chips[i])
> +			pinctrl_add_gpio_range(info->pctl, &gpio_chips[i]->range);
>  
>  	dev_info(&pdev->dev, "initialized AT91 pinctrl driver\n");
>  
> @@ -1681,6 +1685,8 @@ static void at91_gpio_probe_fixup(void)
>  
>  	for (i = 0; i < gpio_banks; i++) {
>  		at91_gpio = gpio_chips[i];
> +		if (!at91_gpio)
> +			continue;

here Nack

as if you disable ANY of the bank that use pioc you break the IRQ support

attached a patch we the idea how to handle the current issue
only compiled not tested (too late here)

Best Regards,
J.
>  
>  		/*
>  		 * GPIO controller are grouped on some SoC:
> -- 
> 2.0.3
> 
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