basic_mmio_gpio: request register regions

Make sure that we get the register regions with request_mem_region()
before ioremap() to make sure we have exclusive access.

Signed-off-by: Jamie Iles <jamie@jamieiles.com>
Acked-by: Anton Vorontsov <cbouatmailru@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

diff --git a/drivers/gpio/basic_mmio_gpio.c b/drivers/gpio/basic_mmio_gpio.c
index 2b2d384..90f7f89 100644 (file)
--- a/drivers/gpio/basic_mmio_gpio.c
+++ b/drivers/gpio/basic_mmio_gpio.c
@@ -192,6 +192,16 @@ static int bgpio_dir_out(struct gpio_chip *gc, unsigned int gpio, int val)
        return 0;
 }
 
+static void __iomem *bgpio_request_and_map(struct device *dev,
+                                          struct resource *res)
+{
+       if (!devm_request_mem_region(dev, res->start, resource_size(res),
+                                    res->name ?: "mmio_gpio"))
+               return NULL;
+
+       return devm_ioremap(dev, res->start, resource_size(res));
+}
+
 static int bgpio_setup_accessors(struct platform_device *pdev,
                                 struct bgpio_chip *bgc)
 {
@@ -258,7 +268,7 @@ static int __devinit bgpio_probe(struct platform_device *pdev)
        if (!bgc)
                return -ENOMEM;
 
-       bgc->reg_dat = devm_ioremap(dev, res_dat->start, dat_sz);
+       bgc->reg_dat = bgpio_request_and_map(dev, res_dat);
        if (!bgc->reg_dat)
                return -ENOMEM;
 
@@ -269,8 +279,8 @@ static int __devinit bgpio_probe(struct platform_device *pdev)
                                resource_size(res_set) != dat_sz)
                        return -EINVAL;
 
-               bgc->reg_set = devm_ioremap(dev, res_set->start, dat_sz);
-               bgc->reg_clr = devm_ioremap(dev, res_clr->start, dat_sz);
+               bgc->reg_set = bgpio_request_and_map(dev, res_set);
+               bgc->reg_clr = bgpio_request_and_map(dev, res_clr);
                if (!bgc->reg_set || !bgc->reg_clr)
                        return -ENOMEM;
        } else if (res_set || res_clr) {