1 files changed, 59 insertions, 31 deletions

diff --git a/drivers/gpio/basic_mmio_gpio.c b/drivers/gpio/basic_mmio_gpio.c
index 90f7f8930d5b..728bc67ee08b 100644
--- a/drivers/gpio/basic_mmio_gpio.c
+++ b/drivers/gpio/basic_mmio_gpio.c
@@ -161,14 +161,6 @@ static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
         unsigned long mask = bgc->pin2mask(bgc, gpio);
         unsigned long flags;
 
-        if (bgc->reg_set) {
-                if (val)
-                        bgc->write_reg(bgc->reg_set, mask);
-                else
-                        bgc->write_reg(bgc->reg_clr, mask);
-                return;
-        }
-
         spin_lock_irqsave(&bgc->lock, flags);
 
         if (val)
@@ -181,6 +173,18 @@ static void bgpio_set(struct gpio_chip *gc, unsigned int gpio, int val)
         spin_unlock_irqrestore(&bgc->lock, flags);
 }
 
+static void bgpio_set_with_clear(struct gpio_chip *gc, unsigned int gpio,
+                                 int val)
+{
+        struct bgpio_chip *bgc = to_bgpio_chip(gc);
+        unsigned long mask = bgc->pin2mask(bgc, gpio);
+
+        if (val)
+                bgc->write_reg(bgc->reg_set, mask);
+        else
+                bgc->write_reg(bgc->reg_clr, mask);
+}
+
 static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
 {
         return 0;
@@ -188,7 +192,8 @@ static int bgpio_dir_in(struct gpio_chip *gc, unsigned int gpio)
 
 static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
 {
-        bgpio_set(gc, gpio, val);
+        gc->set(gc, gpio, val);
+
         return 0;
 }
 
@@ -238,18 +243,25 @@ static int bgpio_setup_accessors(struct platform_device *pdev,
         return 0;
 }
 
-static int __devinit bgpio_probe(struct platform_device *pdev)
+/*
+ * Create the device and allocate the resources.  For setting GPIO's there are
+ * two supported configurations:
+ *
+ *      - single output register resource (named "dat").
+ *      - set/clear pair (named "set" and "clr").
+ *
+ * For the single output register, this drives a 1 by setting a bit and a zero
+ * by clearing a bit.  For the set clr pair, this drives a 1 by setting a bit
+ * in the set register and clears it by setting a bit in the clear register.
+ * The configuration is detected by which resources are present.
+ */
+static int bgpio_setup_io(struct platform_device *pdev,
+                          struct bgpio_chip *bgc)
 {
-        struct device *dev = &pdev->dev;
-        struct bgpio_pdata *pdata = dev_get_platdata(dev);
-        struct bgpio_chip *bgc;
-        struct resource *res_dat;
         struct resource *res_set;
         struct resource *res_clr;
+        struct resource *res_dat;
         resource_size_t dat_sz;
-        int bits;
-        int ret;
-        int ngpio;
 
         res_dat = platform_get_resource_byname(pdev, IORESOURCE_MEM, "dat");
         if (!res_dat)
@@ -259,16 +271,11 @@ static int __devinit bgpio_probe(struct platform_device *pdev)
         if (!is_power_of_2(dat_sz))
                 return -EINVAL;
 
-        bits = dat_sz * 8;
-        ngpio = bits;
-        if (bits > BITS_PER_LONG)
+        bgc->bits = dat_sz * 8;
+        if (bgc->bits > BITS_PER_LONG)
                 return -EINVAL;
 
-        bgc = devm_kzalloc(dev, sizeof(*bgc), GFP_KERNEL);
-        if (!bgc)
-                return -ENOMEM;
-
-        bgc->reg_dat = bgpio_request_and_map(dev, res_dat);
+        bgc->reg_dat = bgpio_request_and_map(&pdev->dev, res_dat);
         if (!bgc->reg_dat)
                 return -ENOMEM;
 
@@ -276,19 +283,41 @@ static int __devinit bgpio_probe(struct platform_device *pdev)
         res_clr = platform_get_resource_byname(pdev, IORESOURCE_MEM, "clr");
         if (res_set && res_clr) {
                 if (resource_size(res_set) != resource_size(res_clr) ||
-                                resource_size(res_set) != dat_sz)
+                    resource_size(res_set) != resource_size(res_dat))
                         return -EINVAL;
 
-                bgc->reg_set = bgpio_request_and_map(dev, res_set);
-                bgc->reg_clr = bgpio_request_and_map(dev, res_clr);
+                bgc->reg_set = bgpio_request_and_map(&pdev->dev, res_set);
+                bgc->reg_clr = bgpio_request_and_map(&pdev->dev, res_clr);
                 if (!bgc->reg_set || !bgc->reg_clr)
                         return -ENOMEM;
+
+                bgc->gc.set = bgpio_set_with_clear;
         } else if (res_set || res_clr) {
                 return -EINVAL;
+        } else {
+                bgc->gc.set = bgpio_set;
         }
 
-        spin_lock_init(&bgc->lock);
+        return 0;
+}
+
+static int __devinit bgpio_probe(struct platform_device *pdev)
+{
+        struct device *dev = &pdev->dev;
+        struct bgpio_pdata *pdata = dev_get_platdata(dev);
+        struct bgpio_chip *bgc;
+        int ret;
+        int ngpio;
+
+        bgc = devm_kzalloc(dev, sizeof(*bgc), GFP_KERNEL);
+        if (!bgc)
+                return -ENOMEM;
+
+        ret = bgpio_setup_io(pdev, bgc);
+        if (ret)
+                return ret;
 
+        ngpio = bgc->bits;
         if (pdata) {
                 bgc->gc.base = pdata->base;
                 if (pdata->ngpio > 0)
@@ -297,18 +326,17 @@ static int __devinit bgpio_probe(struct platform_device *pdev)
                 bgc->gc.base = -1;
         }
 
-        bgc->bits = bits;
         ret = bgpio_setup_accessors(pdev, bgc);
         if (ret)
                 return ret;
 
+        spin_lock_init(&bgc->lock);
         bgc->data = bgc->read_reg(bgc->reg_dat);
 
         bgc->gc.ngpio = ngpio;
         bgc->gc.direction_input = bgpio_dir_in;
         bgc->gc.direction_output = bgpio_dir_out;
         bgc->gc.get = bgpio_get;
-        bgc->gc.set = bgpio_set;
         bgc->gc.dev = dev;
         bgc->gc.label = dev_name(dev);