From mboxrd@z Thu Jan  1 00:00:00 1970
From: srinivas.kandagatla@linaro.org (Srinivas Kandagatla)
Date: Thu, 04 Sep 2014 19:08:12 +0100
Subject: [PATCH] pinctrl: st: Add remove function and remove gpio_chip
 on failure
In-Reply-To: <1409409935-8775-1-git-send-email-pramod.gurav@smartplayin.com>
References: <1409409935-8775-1-git-send-email-pramod.gurav@smartplayin.com>
Message-ID: <5408AA8C.7040100@linaro.org>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

Pramod,
sorry for delay in reply as I was travelling, still in Jet lag.
> Signed-off-by: Pramod Gurav <pramod.gurav@smartplayin.com>
> ---
>   drivers/pinctrl/pinctrl-st.c |   25 +++++++++++++++++++++++++
>   1 files changed, 25 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/pinctrl/pinctrl-st.c b/drivers/pinctrl/pinctrl-st.c
> index 5475374..9296845 100644
> --- a/drivers/pinctrl/pinctrl-st.c
> +++ b/drivers/pinctrl/pinctrl-st.c
> @@ -1517,6 +1517,7 @@ static int st_gpiolib_register_bank(struct st_pinctrl *info,
>   					   0, handle_simple_irq,
>   					   IRQ_TYPE_LEVEL_LOW);
>   		if (err) {
> +			gpiochip_remove(&bank->gpio_chip);
This change-set looks good.
IMO, you can send a patch for this change set.

>   			dev_info(dev, "could not add irqchip\n");
>   			return err;
>   		}
> @@ -1685,6 +1686,29 @@ static int st_pctl_probe(struct platform_device *pdev)
>   	return 0;
>   }
>

> +static int st_pctl_remove(struct platform_device *pdev)
> +{
Ideally this driver will not be removed, as other drivers depend on 
this, even the serial.

so I see no big achievement in adding the remove functionality, as this 
is going to be a dead code and would never be tested.

> +	struct st_pinctrl *info = platform_get_drvdata(pdev);
> +	struct device_node *np = pdev->dev.of_node;
> +	struct device_node *child;
> +	struct gpio_chip gpio_chip;
> +	int bank = 0;
> +

> +	if (info->nbanks) {
> +		for_each_child_of_node(np, child) {
> +			if (of_property_read_bool(child, "gpio-controller")) {
We should not re-parse the DT nodes once we are done with it in the probe.

> +				gpio_chip = info->banks[bank].gpio_chip;
> +				gpiochip_remove(&gpio_chip);
> +				bank++;
> +			}
> +		}
> +	}
> +

I think the logic is very simple:

	while (nbanks--)
		gpiochip_remove(&info->banks[bank++].gpio_chip))


thanks,
srini
> +	pinctrl_unregister(info->pctl);
> +
> +	return 0;
> +}
> +
>   static struct platform_driver st_pctl_driver = {
>   	.driver = {
>   		.name = "st-pinctrl",
> @@ -1692,6 +1716,7 @@ static struct platform_driver st_pctl_driver = {
>   		.of_match_table = st_pctl_of_match,
>   	},
>   	.probe = st_pctl_probe,
> +	.remove = st_pctl_remove,
>   };
>
>   static int __init st_pctl_init(void)
>