ARM: 5972/1: nomadik-gpio: convert to platform driver

On the U8500 platform there are four GPIO blocks, each with a 4K address
space, including the peripheral identification.  However, each of these
blocks have a varying number of banks, each of which have 32 GPIOs and
an interrupt line.

The current nomadik-gpio driver implementation can handle each of these
sub-banks easily with one instance each, but cannot as-is be hooked up
to them because it is an AMBA driver and it expects to see a peripheral
with the appropriate peripheral ids but having only one bank and only
one interrupt.

Solve this by converting the driver to a platform driver.

Acked-by: Alessandro Rubini <rubini@unipv.it>
Acked-by: Linus Walleij <linus.walleij@stericsson.com>
Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

2 files changed, 43 insertions, 32 deletions

diff --git a/arch/arm/plat-nomadik/gpio.c b/arch/arm/plat-nomadik/gpio.c
index 4c3ea1a922ac..092f380063b3 100644
--- a/arch/arm/plat-nomadik/gpio.c
+++ b/arch/arm/plat-nomadik/gpio.c
@@ -13,7 +13,7 @@
 #include <linux/module.h>
 #include <linux/init.h>
 #include <linux/device.h>
-#include <linux/amba/bus.h>
+#include <linux/platform_device.h>
 #include <linux/io.h>
 #include <linux/gpio.h>
 #include <linux/spinlock.h>
@@ -303,30 +303,48 @@ static struct gpio_chip nmk_gpio_template = {
         .can_sleep              = 0,
 };
 
-static int __init nmk_gpio_probe(struct amba_device *dev, struct amba_id *id)
+static int __init nmk_gpio_probe(struct platform_device *dev)
 {
-        struct nmk_gpio_platform_data *pdata;
+        struct nmk_gpio_platform_data *pdata = dev->dev.platform_data;
         struct nmk_gpio_chip *nmk_chip;
         struct gpio_chip *chip;
+        struct resource *res;
+        int irq;
         int ret;
 
-        pdata = dev->dev.platform_data;
-        ret = amba_request_regions(dev, pdata->name);
-        if (ret)
-                return ret;
+        if (!pdata)
+                return -ENODEV;
+
+        res = platform_get_resource(dev, IORESOURCE_MEM, 0);
+        if (!res) {
+                ret = -ENOENT;
+                goto out;
+        }
+
+        irq = platform_get_irq(dev, 0);
+        if (irq < 0) {
+                ret = irq;
+                goto out;
+        }
+
+        if (request_mem_region(res->start, resource_size(res),
+                               dev_name(&dev->dev)) == NULL) {
+                ret = -EBUSY;
+                goto out;
+        }
 
         nmk_chip = kzalloc(sizeof(*nmk_chip), GFP_KERNEL);
         if (!nmk_chip) {
                 ret = -ENOMEM;
-                goto out_amba;
+                goto out_release;
         }
         /*
          * The virt address in nmk_chip->addr is in the nomadik register space,
          * so we can simply convert the resource address, without remapping
          */
-        nmk_chip->addr = io_p2v(dev->res.start);
+        nmk_chip->addr = io_p2v(res->start);
         nmk_chip->chip = nmk_gpio_template;
-        nmk_chip->parent_irq = pdata->parent_irq;
+        nmk_chip->parent_irq = irq;
         spin_lock_init(&nmk_chip->lock);
 
         chip = &nmk_chip->chip;
@@ -339,7 +357,7 @@ static int __init nmk_gpio_probe(struct amba_device *dev, struct amba_id *id)
         if (ret)
                 goto out_free;
 
-        amba_set_drvdata(dev, nmk_chip);
+        platform_set_drvdata(dev, nmk_chip);
 
         nmk_gpio_init_irq(nmk_chip);
 
@@ -347,51 +365,45 @@ static int __init nmk_gpio_probe(struct amba_device *dev, struct amba_id *id)
                  nmk_chip->chip.base, nmk_chip->chip.base+31, nmk_chip->addr);
         return 0;
 
- out_free:
+out_free:
         kfree(nmk_chip);
- out_amba:
-        amba_release_regions(dev);
+out_release:
+        release_mem_region(res->start, resource_size(res));
+out:
         dev_err(&dev->dev, "Failure %i for GPIO %i-%i\n", ret,
                   pdata->first_gpio, pdata->first_gpio+31);
         return ret;
 }
 
-static int nmk_gpio_remove(struct amba_device *dev)
+static int __exit nmk_gpio_remove(struct platform_device *dev)
 {
         struct nmk_gpio_chip *nmk_chip;
+        struct resource *res;
+
+        res = platform_get_resource(dev, IORESOURCE_MEM, 0);
 
-        nmk_chip = amba_get_drvdata(dev);
+        nmk_chip = platform_get_drvdata(dev);
         gpiochip_remove(&nmk_chip->chip);
         kfree(nmk_chip);
-        amba_release_regions(dev);
+        release_mem_region(res->start, resource_size(res));
         return 0;
 }
 
 
-/* We have 0x1f080060 and 0x1f180060, accept both using the mask */
-static struct amba_id nmk_gpio_ids[] = {
-        {
-                .id     = 0x1f080060,
-                .mask   = 0xffefffff,
-        },
-        {0, 0},
-};
-
-static struct amba_driver nmk_gpio_driver = {
-        .drv = {
+static struct platform_driver nmk_gpio_driver = {
+        .driver = {
                 .owner = THIS_MODULE,
                 .name = "gpio",
                 },
         .probe = nmk_gpio_probe,
-        .remove = nmk_gpio_remove,
+        .remove = __exit_p(nmk_gpio_remove),
         .suspend = NULL, /* to be done */
         .resume = NULL,
-        .id_table = nmk_gpio_ids,
 };
 
 static int __init nmk_gpio_init(void)
 {
-        return amba_driver_register(&nmk_gpio_driver);
+        return platform_driver_register(&nmk_gpio_driver);
 }
 
 arch_initcall(nmk_gpio_init);
diff --git a/arch/arm/plat-nomadik/include/plat/gpio.h b/arch/arm/plat-nomadik/include/plat/gpio.h
index 1d665a0abb87..4200811249ca 100644
--- a/arch/arm/plat-nomadik/include/plat/gpio.h
+++ b/arch/arm/plat-nomadik/include/plat/gpio.h
@@ -65,7 +65,6 @@ struct nmk_gpio_platform_data {
         char *name;
         int first_gpio;
         int first_irq;
-        int parent_irq;
 };
 
 #endif /* __ASM_PLAT_GPIO_H */