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-rw-r--r--drivers/gpio/basic_mmio_gpio.c90
1 files changed, 59 insertions, 31 deletions
diff --git a/drivers/gpio/basic_mmio_gpio.c b/drivers/gpio/basic_mmio_gpio.c
index 90f7f8930d5..728bc67ee08 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);