Re: [PATCH 2/2] gpio/omap: add *remove* callback in platform_driver

Kevin Hilman
2012-07-11T23:25:44Z

Tarun Kanti DebBarma <tarun.kanti@ti.com> writes:

> Add *remove* callback so that necessary cleanup operations are
> performed when device is unregistered.

How was this tested? on what platforms?

> The device is deleted
> from the list and associated clock handle is released by
> calling clk_put() and irq descriptor is released using the
> irq_free_desc() api.

There is quite a bit of other things to do in remove to properly cleanup
what is done in probe.

Also, what happens when a 'remove' is triwhen there are GPIOs that
are still requested and in use, especially if they are GPIO IRQs.

Also, what about runtime PM?

In short, this seems very premature and I suspect untested.

Kevin

> Signed-off-by: Tarun Kanti DebBarma <tarun.kanti@ti.com>
> Reported-by: Paul Walmsley <paul@pwsan.com>
> Reviewed-by: Jon Hunter <jon-hunter@ti.com>
> Cc: Kevin Hilman <khilman@ti.com>
> Cc: Rajendra Nayak <rnayak@ti.com>
> Cc: Santosh Shilimkar <santosh.shilimkar@ti.com>
> Cc: Cousson, Benoit <b-cousson@ti.com>
> Cc: Paul Walmsley <paul@pwsan.com>
> ---
> drivers/gpio/gpio-omap.c | 30 ++++++++++++++++++++++++++++++
> 1 files changed, 30 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/gpio/gpio-omap.c b/drivers/gpio/gpio-omap.c
> index afecdcc..08929d5 100644
> --- a/drivers/gpio/gpio-omap.c
> +++ b/drivers/gpio/gpio-omap.c
> @@ -1140,6 +1140,35 @@ static int __devinit omap_gpio_probe(struct platform_device *pdev)
> return ret;
> }
>
> +/**
> + * omap_gpio_remove - cleanup a registered gpio device
> + * @pdev: pointer to current gpio platform device
> + *
> + * Called by driver framework whenever a gpio device is unregistered.
> + * GPIO is deleted from the list and associated clock handle freed.
> + */
> +static int __devexit omap_gpio_remove(struct platform_device *pdev)
> +{
> + struct device *dev = &pdev->dev;
> + struct gpio_bank *bank;
> + unsigned long flags;
> + int ret = -EINVAL;
> +
> + list_for_each_entry(bank, &omap_gpio_list, node) {
> + spin_lock_irqsave(&bank->lock, flags);
> + if (bank->dev == dev) {
> + list_del(&bank->node);
> + clk_put(bank->dbck);
> + irq_free_desc(bank->irq_base);
> + ret = 0;
> + spin_unlock_irqrestore(&bank->lock, flags);
> + break;
> + }
> + spin_unlock_irqrestore(&bank->lock, flags);
> + }
> + return ret;
> +}
> +
> #ifdef CONFIG_ARCH_OMAP2PLUS
>
> #if defined(CONFIG_PM_RUNTIME)
> @@ -1466,6 +1495,7 @@ MODULE_DEVICE_TABLE(of, omap_gpio_match);
>
> static struct platform_driver omap_gpio_driver = {
> .probe = omap_gpio_probe,
> + .remove = __devexit_p(omap_gpio_remove),
> .driver = {
> .name = "omap_gpio",
> .pm = &gpio_pm_ops,