[PATCH 1/1] gpio: Provide the STMPE GPIO driver with its own IRQ Domain

[Lee Jones]

On Fri, 23 Nov 2012, Lee Jones wrote:

> The STMPE GPIO driver can be used as an IRQ controller by some
> related devices. Here we provide it with its very own IRQ Domain
> so that IRQs can be issued dynamically. This will stand the
> driver in good stead when it is enabled for Device Tree, as this
> it a prerequisite.
> 
> Cc: Grant Likely <grant.likely at secretlab.ca>
> Reviewed-by: Viresh Kumar <viresh.kumar at linaro.org>
> Signed-off-by: Lee Jones <lee.jones at linaro.org>
> ---
>  drivers/gpio/gpio-stmpe.c |   67 +++++++++++++++++++++++++++------------------
>  1 file changed, 41 insertions(+), 26 deletions(-)
> 
> diff --git a/drivers/gpio/gpio-stmpe.c b/drivers/gpio/gpio-stmpe.c
> index dce3472..5a87ed6 100644
> --- a/drivers/gpio/gpio-stmpe.c
> +++ b/drivers/gpio/gpio-stmpe.c
> @@ -11,6 +11,7 @@
>  #include <linux/slab.h>
>  #include <linux/gpio.h>
>  #include <linux/irq.h>
> +#include <linux/irqdomain.h>
>  #include <linux/interrupt.h>
>  #include <linux/mfd/stmpe.h>
>  
> @@ -28,6 +29,7 @@ struct stmpe_gpio {
>  	struct stmpe *stmpe;
>  	struct device *dev;
>  	struct mutex irq_lock;
> +	struct irq_domain *domain;
>  
>  	int irq_base;
>  	unsigned norequest_mask;
> @@ -267,38 +269,55 @@ static irqreturn_t stmpe_gpio_irq(int irq, void *dev)
>  	return IRQ_HANDLED;
>  }
>  
> -static int __devinit stmpe_gpio_irq_init(struct stmpe_gpio *stmpe_gpio)
> +int stmpe_gpio_irq_map(struct irq_domain *d, unsigned int virq,
> +		       irq_hw_number_t hwirq)
>  {
> -	int base = stmpe_gpio->irq_base;
> -	int irq;
> +	struct stmpe_gpio *stmpe_gpio = d->host_data;
> +
> +	if (!stmpe_gpio)
> +		return -EINVAL;
>  
> -	for (irq = base; irq < base + stmpe_gpio->chip.ngpio; irq++) {
> -		irq_set_chip_data(irq, stmpe_gpio);
> -		irq_set_chip_and_handler(irq, &stmpe_gpio_irq_chip,
> -					 handle_simple_irq);
> -		irq_set_nested_thread(irq, 1);
> +	irq_set_chip_data(hwirq, stmpe_gpio);
> +	irq_set_chip_and_handler(hwirq, &stmpe_gpio_irq_chip,
> +				 handle_simple_irq);
> +	irq_set_nested_thread(hwirq, 1);
>  #ifdef CONFIG_ARM
> -		set_irq_flags(irq, IRQF_VALID);
> +	set_irq_flags(hwirq, IRQF_VALID);
>  #else
> -		irq_set_noprobe(irq);
> +	irq_set_noprobe(hwirq);
>  #endif
> -	}
>  
>  	return 0;
>  }
>  
> -static void stmpe_gpio_irq_remove(struct stmpe_gpio *stmpe_gpio)
> +void stmpe_gpio_irq_unmap(struct irq_domain *d, unsigned int virq)
>  {
> -	int base = stmpe_gpio->irq_base;
> -	int irq;
> -
> -	for (irq = base; irq < base + stmpe_gpio->chip.ngpio; irq++) {
>  #ifdef CONFIG_ARM
> -		set_irq_flags(irq, 0);
> +	set_irq_flags(virq, 0);
>  #endif
> -		irq_set_chip_and_handler(irq, NULL, NULL);
> -		irq_set_chip_data(irq, NULL);
> +	irq_set_chip_and_handler(virq, NULL, NULL);
> +	irq_set_chip_data(virq, NULL);
> +}
> +
> +static const struct irq_domain_ops stmpe_gpio_irq_simple_ops = {
> +	.unmap = stmpe_gpio_irq_unmap,
> +	.map = stmpe_gpio_irq_map,
> +	.xlate = irq_domain_xlate_twocell,
> +};
> +
> +static int __devinit stmpe_gpio_irq_init(struct stmpe_gpio *stmpe_gpio)
> +{
> +	int base = stmpe_gpio->irq_base;
> +
> +	stmpe_gpio->domain = irq_domain_add_simple(NULL,
> +				stmpe_gpio->chip.ngpio, base,
> +				&stmpe_gpio_irq_simple_ops, stmpe_gpio);
> +	if (!stmpe_gpio->domain) {
> +		dev_err(stmpe_gpio->dev, "failed to create irqdomain\n");
> +		return -ENOSYS;
>  	}
> +
> +	return 0;
>  }
>  
>  static int __devinit stmpe_gpio_probe(struct platform_device *pdev)
> @@ -348,7 +367,7 @@ static int __devinit stmpe_gpio_probe(struct platform_device *pdev)
>  				IRQF_ONESHOT, "stmpe-gpio", stmpe_gpio);
>  		if (ret) {
>  			dev_err(&pdev->dev, "unable to get irq: %d\n", ret);
> -			goto out_removeirq;
> +			goto out_disable;
>  		}
>  	}
>  
> @@ -368,9 +387,6 @@ static int __devinit stmpe_gpio_probe(struct platform_device *pdev)
>  out_freeirq:
>  	if (irq >= 0)
>  		free_irq(irq, stmpe_gpio);
> -out_removeirq:
> -	if (irq >= 0)
> -		stmpe_gpio_irq_remove(stmpe_gpio);
>  out_disable:
>  	stmpe_disable(stmpe, STMPE_BLOCK_GPIO);
>  out_free:
> @@ -398,10 +414,9 @@ static int __devexit stmpe_gpio_remove(struct platform_device *pdev)
>  
>  	stmpe_disable(stmpe, STMPE_BLOCK_GPIO);
>  
> -	if (irq >= 0) {
> +	if (irq >= 0)
>  		free_irq(irq, stmpe_gpio);
> -		stmpe_gpio_irq_remove(stmpe_gpio);
> -	}
> +
>  	platform_set_drvdata(pdev, NULL);
>  	kfree(stmpe_gpio);
>  
> -- 
> 1.7.9.5

Poke.

-- 
Lee Jones
Linaro ST-Ericsson Landing Team Lead
Linaro.org │ Open source software for ARM SoCs
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