Re: [PATCH 2/2 v2] gpio/stmpe: support no-irq mode

From: Viresh Kumar
Date: Thu Jan 26 2012 - 23:20:08 EST


On 1/27/2012 2:47 AM, Linus WALLEIJ wrote:
> From: Chris Blair <chris.blair@xxxxxxxxxxxxxx>
>
> Adds support for boards which have an STMPE GPIO device without the
> interrupt pin connected. This means that no interrupt can be received
> but the GPIO pins can still be driven and read.
>
> Cc: Grant Likely <grant.likely@xxxxxxxxxxxx>
> Acked-by: Viresh Kumar <viresh.kumar@xxxxxx>
> Tested-by: Michel Jaouen <michel.jaouen@xxxxxxxxxxxxxx>
> Signed-off-by: Chris Blair <chris.blair@xxxxxxxxxxxxxx>
> ---
> ChangeLog v1->v2:
> - Removes the use of the new no_irq platform data member and
> instead uses the value obtained for the cell irq to know if irqs
> are supported or not. If irqs are not supported, the device
> will not have been given an irq resource and the irq value
> will be invalid.
>
> This depends on the previous patch to the MFD
> code so should better be merged into the MFD tree with the
> previous patch.
> ---
> drivers/gpio/gpio-stmpe.c | 41 +++++++++++++++++++++++++----------------
> 1 files changed, 25 insertions(+), 16 deletions(-)
>
> diff --git a/drivers/gpio/gpio-stmpe.c b/drivers/gpio/gpio-stmpe.c
> index 87a68a8..094c5c4 100644
> --- a/drivers/gpio/gpio-stmpe.c
> +++ b/drivers/gpio/gpio-stmpe.c
> @@ -307,13 +307,11 @@ static int __devinit stmpe_gpio_probe(struct platform_device *pdev)
> struct stmpe_gpio_platform_data *pdata;
> struct stmpe_gpio *stmpe_gpio;
> int ret;
> - int irq;
> + int irq = 0;
>
> pdata = stmpe->pdata->gpio;
>
> irq = platform_get_irq(pdev, 0);
> - if (irq < 0)
> - return irq;
>
> stmpe_gpio = kzalloc(sizeof(struct stmpe_gpio), GFP_KERNEL);
> if (!stmpe_gpio)
> @@ -330,21 +328,28 @@ static int __devinit stmpe_gpio_probe(struct platform_device *pdev)
> stmpe_gpio->chip.dev = &pdev->dev;
> stmpe_gpio->chip.base = pdata ? pdata->gpio_base : -1;
>
> - stmpe_gpio->irq_base = stmpe->irq_base + STMPE_INT_GPIO(0);
> + if (irq >= 0)
> + stmpe_gpio->irq_base = stmpe->irq_base + STMPE_INT_GPIO(0);
> + else
> + dev_info(&pdev->dev,
> + "device configured in no-irq mode; "
> + "irqs are not available\n");
>
> ret = stmpe_enable(stmpe, STMPE_BLOCK_GPIO);
> if (ret)
> goto out_free;
>
> - ret = stmpe_gpio_irq_init(stmpe_gpio);
> - if (ret)
> - goto out_disable;
> + if (irq >= 0) {
> + ret = stmpe_gpio_irq_init(stmpe_gpio);
> + if (ret)
> + goto out_disable;
>
> - ret = request_threaded_irq(irq, NULL, stmpe_gpio_irq, IRQF_ONESHOT,
> - "stmpe-gpio", stmpe_gpio);
> - if (ret) {
> - dev_err(&pdev->dev, "unable to get irq: %d\n", ret);
> - goto out_removeirq;
> + ret = request_threaded_irq(irq, NULL, stmpe_gpio_irq,
> + IRQF_ONESHOT, "stmpe-gpio", stmpe_gpio);
> + if (ret) {
> + dev_err(&pdev->dev, "unable to get irq: %d\n", ret);
> + goto out_removeirq;
> + }
> }
>
> ret = gpiochip_add(&stmpe_gpio->chip);
> @@ -361,9 +366,11 @@ static int __devinit stmpe_gpio_probe(struct platform_device *pdev)
> return 0;
>
> out_freeirq:
> - free_irq(irq, stmpe_gpio);
> + if (irq >= 0)
> + free_irq(irq, stmpe_gpio);
> out_removeirq:
> - stmpe_gpio_irq_remove(stmpe_gpio);
> + if (irq >= 0)
> + stmpe_gpio_irq_remove(stmpe_gpio);
> out_disable:
> stmpe_disable(stmpe, STMPE_BLOCK_GPIO);
> out_free:
> @@ -391,8 +398,10 @@ static int __devexit stmpe_gpio_remove(struct platform_device *pdev)
>
> stmpe_disable(stmpe, STMPE_BLOCK_GPIO);
>
> - free_irq(irq, stmpe_gpio);
> - stmpe_gpio_irq_remove(stmpe_gpio);
> + if (irq >= 0) {
> + free_irq(irq, stmpe_gpio);
> + stmpe_gpio_irq_remove(stmpe_gpio);
> + }
> platform_set_drvdata(pdev, NULL);
> kfree(stmpe_gpio);
>

Acked-by: Viresh Kumar <viresh.kumar@xxxxxx>

--
viresh
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/