[PATCH] gpio/mxc: convert gpio-mxc to use generic irq chip

[Sascha Hauer]

On Tue, Jun 07, 2011 at 04:25:37PM +0800, Shawn Guo wrote:
> The patch converts gpio-mxc driver to use generic irq chip.
> 
> Signed-off-by: Shawn Guo <shawn.guo at linaro.org>

Acked-by: Sascha Hauer <s.hauer at pengutronix.de>

> ---
>  drivers/gpio/Kconfig    |    1 +
>  drivers/gpio/gpio-mxc.c |   90 +++++++++++++++--------------------------------
>  2 files changed, 30 insertions(+), 61 deletions(-)
> 
> diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
> index d973abd..ee8802f 100644
> --- a/drivers/gpio/Kconfig
> +++ b/drivers/gpio/Kconfig
> @@ -97,6 +97,7 @@ config GPIO_MXC
>  	def_bool y
>  	depends on ARCH_MXC
>  	select GPIO_BASIC_MMIO_CORE
> +	select GENERIC_IRQ_CHIP
>  
>  config GPIO_PLAT_SAMSUNG
>  	bool "Samsung SoCs GPIO library support"
> diff --git a/drivers/gpio/gpio-mxc.c b/drivers/gpio/gpio-mxc.c
> index b351952893..950e53a 100644
> --- a/drivers/gpio/gpio-mxc.c
> +++ b/drivers/gpio/gpio-mxc.c
> @@ -65,46 +65,11 @@ static LIST_HEAD(mxc_gpio_ports);
>  
>  /* Note: This driver assumes 32 GPIOs are handled in one register */
>  
> -static void _clear_gpio_irqstatus(struct mxc_gpio_port *port, u32 index)
> -{
> -	writel(1 << index, port->base + GPIO_ISR);
> -}
> -
> -static void _set_gpio_irqenable(struct mxc_gpio_port *port, u32 index,
> -				int enable)
> -{
> -	u32 l;
> -
> -	l = readl(port->base + GPIO_IMR);
> -	l = (l & (~(1 << index))) | (!!enable << index);
> -	writel(l, port->base + GPIO_IMR);
> -}
> -
> -static void gpio_ack_irq(struct irq_data *d)
> -{
> -	struct mxc_gpio_port *port = irq_data_get_irq_chip_data(d);
> -	u32 gpio = irq_to_gpio(d->irq);
> -	_clear_gpio_irqstatus(port, gpio & 0x1f);
> -}
> -
> -static void gpio_mask_irq(struct irq_data *d)
> -{
> -	struct mxc_gpio_port *port = irq_data_get_irq_chip_data(d);
> -	u32 gpio = irq_to_gpio(d->irq);
> -	_set_gpio_irqenable(port, gpio & 0x1f, 0);
> -}
> -
> -static void gpio_unmask_irq(struct irq_data *d)
> -{
> -	struct mxc_gpio_port *port = irq_data_get_irq_chip_data(d);
> -	u32 gpio = irq_to_gpio(d->irq);
> -	_set_gpio_irqenable(port, gpio & 0x1f, 1);
> -}
> -
>  static int gpio_set_irq_type(struct irq_data *d, u32 type)
>  {
>  	u32 gpio = irq_to_gpio(d->irq);
> -	struct mxc_gpio_port *port = irq_data_get_irq_chip_data(d);
> +	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
> +	struct mxc_gpio_port *port = gc->private;
>  	u32 bit, val;
>  	int edge;
>  	void __iomem *reg = port->base;
> @@ -142,7 +107,7 @@ static int gpio_set_irq_type(struct irq_data *d, u32 type)
>  	bit = gpio & 0xf;
>  	val = readl(reg) & ~(0x3 << (bit << 1));
>  	writel(val | (edge << (bit << 1)), reg);
> -	_clear_gpio_irqstatus(port, gpio & 0x1f);
> +	writel(1 << (gpio & 0x1f), port->base + GPIO_ISR);
>  
>  	return 0;
>  }
> @@ -231,7 +196,8 @@ static int gpio_set_wake_irq(struct irq_data *d, u32 enable)
>  {
>  	u32 gpio = irq_to_gpio(d->irq);
>  	u32 gpio_idx = gpio & 0x1F;
> -	struct mxc_gpio_port *port = irq_data_get_irq_chip_data(d);
> +	struct irq_chip_generic *gc = irq_data_get_irq_chip_data(d);
> +	struct mxc_gpio_port *port = gc->private;
>  
>  	if (enable) {
>  		if (port->irq_high && (gpio_idx >= 16))
> @@ -248,26 +214,33 @@ static int gpio_set_wake_irq(struct irq_data *d, u32 enable)
>  	return 0;
>  }
>  
> -static struct irq_chip gpio_irq_chip = {
> -	.name = "GPIO",
> -	.irq_ack = gpio_ack_irq,
> -	.irq_mask = gpio_mask_irq,
> -	.irq_unmask = gpio_unmask_irq,
> -	.irq_set_type = gpio_set_irq_type,
> -	.irq_set_wake = gpio_set_wake_irq,
> -};
> -
> -/*
> - * This lock class tells lockdep that GPIO irqs are in a different
> - * category than their parents, so it won't report false recursion.
> - */
> -static struct lock_class_key gpio_lock_class;
> +static void __init mxc_gpio_init_gc(struct mxc_gpio_port *port)
> +{
> +	struct irq_chip_generic *gc;
> +	struct irq_chip_type *ct;
> +
> +	gc = irq_alloc_generic_chip("gpio-mxc", 1, port->virtual_irq_start,
> +				    port->base, handle_level_irq);
> +	gc->private = port;
> +
> +	ct = gc->chip_types;
> +	ct->chip.irq_ack = irq_gc_ack,
> +	ct->chip.irq_mask = irq_gc_mask_clr_bit;
> +	ct->chip.irq_unmask = irq_gc_mask_set_bit;
> +	ct->chip.irq_set_type = gpio_set_irq_type;
> +	ct->chip.irq_set_wake = gpio_set_wake_irq,
> +	ct->regs.ack = GPIO_ISR;
> +	ct->regs.mask = GPIO_IMR;
> +
> +	irq_setup_generic_chip(gc, IRQ_MSK(32), IRQ_GC_INIT_NESTED_LOCK,
> +			       IRQ_NOREQUEST, 0);
> +}
>  
>  static int __devinit mxc_gpio_probe(struct platform_device *pdev)
>  {
>  	struct mxc_gpio_port *port;
>  	struct resource *iores;
> -	int err, i;
> +	int err;
>  
>  	port = kzalloc(sizeof(struct mxc_gpio_port), GFP_KERNEL);
>  	if (!port)
> @@ -304,13 +277,8 @@ static int __devinit mxc_gpio_probe(struct platform_device *pdev)
>  	writel(0, port->base + GPIO_IMR);
>  	writel(~0, port->base + GPIO_ISR);
>  
> -	for (i = port->virtual_irq_start;
> -		i < port->virtual_irq_start + 32; i++) {
> -		irq_set_lockdep_class(i, &gpio_lock_class);
> -		irq_set_chip_and_handler(i, &gpio_irq_chip, handle_level_irq);
> -		set_irq_flags(i, IRQF_VALID);
> -		irq_set_chip_data(i, port);
> -	}
> +	/* gpio-mxc can be a generic irq chip */
> +	mxc_gpio_init_gc(port);
>  
>  	if (cpu_is_mx2()) {
>  		/* setup one handler for all GPIO interrupts */
> -- 
> 1.7.4.1
> 
> 

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