Commit 17cf5011 authored by Russell King's avatar Russell King
Browse files

ARM: sa1111: implement a gpio_chip for SA1111 GPIOs 



Add a gpio_chip instance for SA1111 GPIOs.  This allows us to use
gpiolib to lookup and manipulate SA1111 GPIOs.

Signed-off-by: default avatarRussell King <rmk+kernel@armlinux.org.uk>
parent ccb7d854

arch/arm/common/sa1111.c

+166 −0
Original line number Diff line number Diff line
@@ -15,6 +15,7 @@ 
 * from machine specific code with proper arguments when required.

 */

#include <linux/module.h>

#include <linux/gpio/driver.h>

#include <linux/init.h>

#include <linux/irq.h>

#include <linux/kernel.h>
@@ -107,6 +108,7 @@ struct sa1111 { 
	spinlock_t	lock;

	void __iomem	*base;

	struct sa1111_platform_data *pdata;

	struct gpio_chip gc;

#ifdef CONFIG_PM

	void		*saved_state;

#endif
@@ -527,6 +529,163 @@ static void sa1111_remove_irq(struct sa1111 *sachip) 
	}

}



enum {

	SA1111_GPIO_PXDDR = (SA1111_GPIO_PADDR - SA1111_GPIO_PADDR),

	SA1111_GPIO_PXDRR = (SA1111_GPIO_PADRR - SA1111_GPIO_PADDR),

	SA1111_GPIO_PXDWR = (SA1111_GPIO_PADWR - SA1111_GPIO_PADDR),

	SA1111_GPIO_PXSDR = (SA1111_GPIO_PASDR - SA1111_GPIO_PADDR),

	SA1111_GPIO_PXSSR = (SA1111_GPIO_PASSR - SA1111_GPIO_PADDR),

};



static struct sa1111 *gc_to_sa1111(struct gpio_chip *gc)

{

	return container_of(gc, struct sa1111, gc);

}



static void __iomem *sa1111_gpio_map_reg(struct sa1111 *sachip, unsigned offset)

{

	void __iomem *reg = sachip->base + SA1111_GPIO;



	if (offset < 4)

		return reg + SA1111_GPIO_PADDR;

	if (offset < 10)

		return reg + SA1111_GPIO_PBDDR;

	if (offset < 18)

		return reg + SA1111_GPIO_PCDDR;

	return NULL;

}



static u32 sa1111_gpio_map_bit(unsigned offset)

{

	if (offset < 4)

		return BIT(offset);

	if (offset < 10)

		return BIT(offset - 4);

	if (offset < 18)

		return BIT(offset - 10);

	return 0;

}



static void sa1111_gpio_modify(void __iomem *reg, u32 mask, u32 set)

{

	u32 val;



	val = readl_relaxed(reg);

	val &= ~mask;

	val |= mask & set;

	writel_relaxed(val, reg);

}



static int sa1111_gpio_get_direction(struct gpio_chip *gc, unsigned offset)

{

	struct sa1111 *sachip = gc_to_sa1111(gc);

	void __iomem *reg = sa1111_gpio_map_reg(sachip, offset);

	u32 mask = sa1111_gpio_map_bit(offset);



	return !!(readl_relaxed(reg + SA1111_GPIO_PXDDR) & mask);

}



static int sa1111_gpio_direction_input(struct gpio_chip *gc, unsigned offset)

{

	struct sa1111 *sachip = gc_to_sa1111(gc);

	unsigned long flags;

	void __iomem *reg = sa1111_gpio_map_reg(sachip, offset);

	u32 mask = sa1111_gpio_map_bit(offset);



	spin_lock_irqsave(&sachip->lock, flags);

	sa1111_gpio_modify(reg + SA1111_GPIO_PXDDR, mask, mask);

	sa1111_gpio_modify(reg + SA1111_GPIO_PXSDR, mask, mask);

	spin_unlock_irqrestore(&sachip->lock, flags);



	return 0;

}



static int sa1111_gpio_direction_output(struct gpio_chip *gc, unsigned offset,

	int value)

{

	struct sa1111 *sachip = gc_to_sa1111(gc);

	unsigned long flags;

	void __iomem *reg = sa1111_gpio_map_reg(sachip, offset);

	u32 mask = sa1111_gpio_map_bit(offset);



	spin_lock_irqsave(&sachip->lock, flags);

	sa1111_gpio_modify(reg + SA1111_GPIO_PXDWR, mask, value ? mask : 0);

	sa1111_gpio_modify(reg + SA1111_GPIO_PXSSR, mask, value ? mask : 0);

	sa1111_gpio_modify(reg + SA1111_GPIO_PXDDR, mask, 0);

	sa1111_gpio_modify(reg + SA1111_GPIO_PXSDR, mask, 0);

	spin_unlock_irqrestore(&sachip->lock, flags);



	return 0;

}



static int sa1111_gpio_get(struct gpio_chip *gc, unsigned offset)

{

	struct sa1111 *sachip = gc_to_sa1111(gc);

	void __iomem *reg = sa1111_gpio_map_reg(sachip, offset);

	u32 mask = sa1111_gpio_map_bit(offset);



	return !!(readl_relaxed(reg + SA1111_GPIO_PXDRR) & mask);

}



static void sa1111_gpio_set(struct gpio_chip *gc, unsigned offset, int value)

{

	struct sa1111 *sachip = gc_to_sa1111(gc);

	unsigned long flags;

	void __iomem *reg = sa1111_gpio_map_reg(sachip, offset);

	u32 mask = sa1111_gpio_map_bit(offset);



	spin_lock_irqsave(&sachip->lock, flags);

	sa1111_gpio_modify(reg + SA1111_GPIO_PXDWR, mask, value ? mask : 0);

	sa1111_gpio_modify(reg + SA1111_GPIO_PXSSR, mask, value ? mask : 0);

	spin_unlock_irqrestore(&sachip->lock, flags);

}



static void sa1111_gpio_set_multiple(struct gpio_chip *gc, unsigned long *mask,

	unsigned long *bits)

{

	struct sa1111 *sachip = gc_to_sa1111(gc);

	unsigned long flags;

	void __iomem *reg = sachip->base + SA1111_GPIO;

	u32 msk, val;



	msk = *mask;

	val = *bits;



	spin_lock_irqsave(&sachip->lock, flags);

	sa1111_gpio_modify(reg + SA1111_GPIO_PADWR, msk & 15, val);

	sa1111_gpio_modify(reg + SA1111_GPIO_PASSR, msk & 15, val);

	sa1111_gpio_modify(reg + SA1111_GPIO_PBDWR, (msk >> 4) & 255, val >> 4);

	sa1111_gpio_modify(reg + SA1111_GPIO_PBSSR, (msk >> 4) & 255, val >> 4);

	sa1111_gpio_modify(reg + SA1111_GPIO_PCDWR, (msk >> 12) & 255, val >> 12);

	sa1111_gpio_modify(reg + SA1111_GPIO_PCSSR, (msk >> 12) & 255, val >> 12);

	spin_unlock_irqrestore(&sachip->lock, flags);

}



static int sa1111_gpio_to_irq(struct gpio_chip *gc, unsigned offset)

{

	struct sa1111 *sachip = gc_to_sa1111(gc);



	return sachip->irq_base + offset;

}



static int sa1111_setup_gpios(struct sa1111 *sachip)

{

	sachip->gc.label = "sa1111";

	sachip->gc.parent = sachip->dev;

	sachip->gc.owner = THIS_MODULE;

	sachip->gc.get_direction = sa1111_gpio_get_direction;

	sachip->gc.direction_input = sa1111_gpio_direction_input;

	sachip->gc.direction_output = sa1111_gpio_direction_output;

	sachip->gc.get = sa1111_gpio_get;

	sachip->gc.set = sa1111_gpio_set;

	sachip->gc.set_multiple = sa1111_gpio_set_multiple;

	sachip->gc.to_irq = sa1111_gpio_to_irq;

	sachip->gc.base = -1;

	sachip->gc.ngpio = 18;



	return devm_gpiochip_add_data(sachip->dev, &sachip->gc, sachip);

}



/*

 * Bring the SA1111 out of reset.  This requires a set procedure:

 *  1. nRESET asserted (by hardware)
@@ -773,6 +932,11 @@ static int __sa1111_probe(struct device *me, struct resource *mem, int irq) 
			goto err_clk;

	}



	/* Setup the GPIOs - should really be done after the IRQ setup */

	ret = sa1111_setup_gpios(sachip);

	if (ret)

		goto err_irq;



#ifdef CONFIG_ARCH_SA1100

	{

	unsigned int val;
@@ -815,6 +979,8 @@ static int __sa1111_probe(struct device *me, struct resource *mem, int irq) 


	return 0;



 err_irq:

	sa1111_remove_irq(sachip);

 err_clk:

	clk_disable(sachip->clk);

 err_unmap: