powerpc/5200: Rework GPT driver to also be an IRQ controller

This patch adds IRQ controller support to the MPC5200 General
Purpose Timer (GPT) device driver.  With this patch the mpc5200-gpt
driver supports both GPIO and IRQ functions.

The GPT driver was contained within the mpc52xx_gpio.c file, but this
patch moves it out into a new file (mpc52xx_gpt.c) since it has more
than just GPIO functionality now and it was only grouped with the
mpc52xx-gpio drivers as a matter of convenience before.  Also, this
driver will most likely get extended again to also provide support
for the timer function.

Implementation note: Alternately, I could have tried to implement
the IRQ support as a separate driver and left the GPIO portion alone.
However, multiple functions of this device (ie. GPIO input+interrupt
controller, or timer+GPIO) can be active at the same time and the
registers are shared so it is safer to contain all functionality
within a single driver.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Reviewed-by: Wolfram Sang <w.sang@pengutronix.de>

arch/powerpc/platforms/52xx/Makefile

@@ -1,7 +1,7 @@
 #
 # Makefile for 52xx based boards
 #
-obj-y				+= mpc52xx_pic.o mpc52xx_common.o
+obj-y				+= mpc52xx_pic.o mpc52xx_common.o mpc52xx_gpt.o
 obj-$(CONFIG_PCI)		+= mpc52xx_pci.o
 
 obj-$(CONFIG_PPC_MPC5200_SIMPLE) += mpc5200_simple.o

arch/powerpc/platforms/52xx/mpc52xx_gpio.c

@@ -354,88 +354,6 @@ static struct of_platform_driver mpc52xx_simple_gpiochip_driver = {
 	.remove = mpc52xx_gpiochip_remove,
 };
 
-/*
- * GPIO LIB API implementation for gpt GPIOs.
- *
- * Each gpt only has a single GPIO.
- */
-static int mpc52xx_gpt_gpio_get(struct gpio_chip *gc, unsigned int gpio)
-{
-	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
-	struct mpc52xx_gpt __iomem *regs = mm_gc->regs;
-
-	return (in_be32(&regs->status) & (1 << (31 - 23))) ? 1 : 0;
-}
-
-static void
-mpc52xx_gpt_gpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
-{
-	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
-	struct mpc52xx_gpt __iomem *regs = mm_gc->regs;
-
-	if (val)
-		out_be32(&regs->mode, 0x34);
-	else
-		out_be32(&regs->mode, 0x24);
-
-	pr_debug("%s: gpio: %d val: %d\n", __func__, gpio, val);
-}
-
-static int mpc52xx_gpt_gpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
-{
-	struct of_mm_gpio_chip *mm_gc = to_of_mm_gpio_chip(gc);
-	struct mpc52xx_gpt __iomem *regs = mm_gc->regs;
-
-	out_be32(&regs->mode, 0x04);
-
-	return 0;
-}
-
-static int
-mpc52xx_gpt_gpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
-{
-	mpc52xx_gpt_gpio_set(gc, gpio, val);
-	pr_debug("%s: gpio: %d val: %d\n", __func__, gpio, val);
-
-	return 0;
-}
-
-static int __devinit mpc52xx_gpt_gpiochip_probe(struct of_device *ofdev,
-					const struct of_device_id *match)
-{
-	struct of_mm_gpio_chip *mmchip;
-	struct of_gpio_chip *chip;
-
-	mmchip = kzalloc(sizeof(*mmchip), GFP_KERNEL);
-	if (!mmchip)
-		return -ENOMEM;
-
-	chip = &mmchip->of_gc;
-
-	chip->gpio_cells          = 2;
-	chip->gc.ngpio            = 1;
-	chip->gc.direction_input  = mpc52xx_gpt_gpio_dir_in;
-	chip->gc.direction_output = mpc52xx_gpt_gpio_dir_out;
-	chip->gc.get              = mpc52xx_gpt_gpio_get;
-	chip->gc.set              = mpc52xx_gpt_gpio_set;
-
-	return of_mm_gpiochip_add(ofdev->node, mmchip);
-}
-
-static const struct of_device_id mpc52xx_gpt_gpiochip_match[] = {
-	{
-		.compatible = "fsl,mpc5200-gpt-gpio",
-	},
-	{}
-};
-
-static struct of_platform_driver mpc52xx_gpt_gpiochip_driver = {
-	.name = "gpio_gpt",
-	.match_table = mpc52xx_gpt_gpiochip_match,
-	.probe = mpc52xx_gpt_gpiochip_probe,
-	.remove = mpc52xx_gpiochip_remove,
-};
-
 static int __init mpc52xx_gpio_init(void)
 {
 	if (of_register_platform_driver(&mpc52xx_wkup_gpiochip_driver))
@@ -444,9 +362,6 @@ static int __init mpc52xx_gpio_init(void)
 	if (of_register_platform_driver(&mpc52xx_simple_gpiochip_driver))
 		printk(KERN_ERR "Unable to register simple GPIO driver\n");
 
-	if (of_register_platform_driver(&mpc52xx_gpt_gpiochip_driver))
-		printk(KERN_ERR "Unable to register gpt GPIO driver\n");
-
 	return 0;
 }