Linux-ARM-Kernel Archive on lore.kernel.org

* [PATCH v2 2/9] pinctrl: single: support gpio request and free
From: Haojian Zhuang @ 2012-10-29  1:58 UTC (permalink / raw)
  To: linux-arm-kernel
In-Reply-To: <20121022202805.GG4730@atomide.com>

On Tue, Oct 23, 2012 at 4:28 AM, Tony Lindgren <tony@atomide.com> wrote:
> * Haojian Zhuang <haojian.zhuang@gmail.com> [121022 09:11]:
>> Marvell's PXA/MMP silicon also match the behavior of pinctrl-single.
>> Each pin binds to one register. A lot of pins could be configured
>> as gpio.
>>
>> Now add three properties in below.
>> pinctrl-single,gpio-ranges: gpio range array
>> pinctrl-single,gpio: <gpio base, npins in range, pin base in range>
>> pinctrl-single,gpio-func: <gpio function value in mux>
>>
>> Signed-off-by: Haojian Zhuang <haojian.zhuang@gmail.com>
>> ---
>>  drivers/pinctrl/pinctrl-single.c |   94 +++++++++++++++++++++++++++++++++++++-
>>  1 files changed, 92 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c
>> index 726a729..6a0b24b 100644
>> --- a/drivers/pinctrl/pinctrl-single.c
>> +++ b/drivers/pinctrl/pinctrl-single.c
>> @@ -28,8 +28,10 @@
>>  #define DRIVER_NAME                  "pinctrl-single"
>>  #define PCS_MUX_PINS_NAME            "pinctrl-single,pins"
>>  #define PCS_MUX_BITS_NAME            "pinctrl-single,bits"
>> +#define PCS_GPIO_FUNC_NAME           "pinctrl-single,gpio-func"
>
> I think we can now get rid of these defines, I initially added
> them as we had a bit hard time finding a suitable name for the
> driver. These are only used in one location, so let's not add
> new ones here.
>
I'll fix.

>>  static int pcs_request_gpio(struct pinctrl_dev *pctldev,
>> -                     struct pinctrl_gpio_range *range, unsigned offset)
>> +                         struct pinctrl_gpio_range *range, unsigned pin)
>>  {
>> -     return -ENOTSUPP;
>> +     struct pcs_device *pcs = pinctrl_dev_get_drvdata(pctldev);
>> +     struct pcs_gpio_range *gpio = NULL;
>> +     int end, mux_bytes;
>> +     unsigned data;
>> +
>> +     gpio = container_of(range, struct pcs_gpio_range, range);
>> +     if (!gpio->func_en)
>> +             return 0;
>> +     end = range->pin_base + range->npins - 1;
>> +     if (pin < range->pin_base || pin > end) {
>> +             dev_err(pctldev->dev, "pin %d isn't in the range of "
>> +                     "%d to %d\n", pin, range->pin_base, end);
>> +             return -EINVAL;
>> +     }
>> +     mux_bytes = pcs->width / BITS_PER_BYTE;
>> +     data = pcs_readl(pcs->base + pin * mux_bytes) & ~pcs->fmask;
>> +     data |= gpio->gpio_func;
>> +     pcs_writel(data, pcs->base + pin * mux_bytes);
>> +     return 0;
>>  }
>
> I think I already commented on this one.. Is this safe if you don't
> have GPIOs configured? Or should you return -ENODEV in that case?
>
OK. I'll use ENOTSUPP instead.

 +     gpio = container_of(range, struct pcs_gpio_range, range);
 +     if (!gpio->func_en)
 +             return -ENOTSUPP;

>> +static int __devinit pcs_add_gpio_range(struct device_node *node,
>> +                                     struct pcs_device *pcs)
>> +{
>> +     struct pcs_gpio_range *gpio;
>> +     struct device_node *np;
>> +     const __be32 *list;
>> +     const char list_name[] = "pinctrl-single,gpio-ranges";
>> +     const char name[] = "pinctrl-single";
>> +     u32 gpiores[PCS_MAX_GPIO_VALUES];
>> +     int ret, size, i, mux_bytes = 0;
>> +
>> +     list = of_get_property(node, list_name, &size);
>> +     if (!list)
>> +             return -ENOENT;
>
> Here you should return 0 if not found, otherwise things go bad for
> me at least as I don't have GPIOs configured. See more below.
>
OK. Use return 0 instead.

>> +             gpio->range.name = kmemdup(name, sizeof(name), GFP_KERNEL);
>> +             pinctrl_add_gpio_range(pcs->pctl, &gpio->range);
>
> Just checking.. These get released with pinctrl_unregister() when
> unloading, right? And nothing else to free in pinctrl-single.c
> either?
>
I'll fix.

>> @@ -975,6 +1061,10 @@ static int __devinit pcs_probe(struct platform_device *pdev)
>>               goto free;
>>       }
>>
>> +     ret = pcs_add_gpio_range(np, pcs);
>> +     if (ret < 0)
>> +             return ret;
>> +
>
> Here you need to goto free on error. Maybe just fold in the
> attached fix if that looks OK to you:
>
> --- a/drivers/pinctrl/pinctrl-single.c
> +++ b/drivers/pinctrl/pinctrl-single.c
> @@ -930,7 +930,7 @@ static int __devinit pcs_add_gpio_range(struct device_node *node,
>
>         list = of_get_property(node, list_name, &size);
>         if (!list)
> -               return -ENOENT;
> +               return 0;
>         size = size / sizeof(*list);
>         for (i = 0; i < size; i++) {
>                 np = of_parse_phandle(node, list_name, i);
> @@ -1065,7 +1065,7 @@ static int __devinit pcs_probe(struct platform_device *pdev)
>
>         ret = pcs_add_gpio_range(np, pcs);
>         if (ret < 0)
> -               return ret;
> +               goto free;
>
>         dev_info(pcs->dev, "%i pins at pa %p size %u\n",
>                  pcs->desc.npins, pcs->base, pcs->size);

I'll take your fix into this patch.

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