ARM: pxa: add clk support in gpio driver

Support clk in gpio driver. There's no gpio clock in PXA25x and PXA27x.
So use dummy clk instead. And move the gpio edge initialization into
gpio driver for arch-mmp.

Signed-off-by: Haojian Zhuang <haojian.zhuang@marvell.com>

drivers/gpio/gpio-pxa.c

@@ -11,6 +11,8 @@
  *  it under the terms of the GNU General Public License version 2 as
  *  published by the Free Software Foundation.
  */
+#include <linux/clk.h>
+#include <linux/err.h>
 #include <linux/gpio.h>
 #include <linux/gpio-pxa.h>
 #include <linux/init.h>
@@ -466,7 +468,8 @@ static int __devinit pxa_gpio_probe(struct platform_device *pdev)
 {
 	struct pxa_gpio_chip *c;
 	struct resource *res;
-	int gpio, irq;
+	struct clk *clk;
+	int gpio, irq, ret;
 	int irq0 = 0, irq1 = 0, irq_mux, gpio_offset = 0;
 
 	pxa_last_gpio = pxa_gpio_nums();
@@ -489,6 +492,27 @@ static int __devinit pxa_gpio_probe(struct platform_device *pdev)
 	if (irq0 > 0)
 		gpio_offset = 2;
 
+	clk = clk_get(&pdev->dev, NULL);
+	if (IS_ERR(clk)) {
+		dev_err(&pdev->dev, "Error %ld to get gpio clock\n",
+			PTR_ERR(clk));
+		iounmap(gpio_reg_base);
+		return PTR_ERR(clk);
+	}
+	ret = clk_prepare(clk);
+	if (ret) {
+		clk_put(clk);
+		iounmap(gpio_reg_base);
+		return ret;
+	}
+	ret = clk_enable(clk);
+	if (ret) {
+		clk_unprepare(clk);
+		clk_put(clk);
+		iounmap(gpio_reg_base);
+		return ret;
+	}
+
 	/* Initialize GPIO chips */
 	pxa_init_gpio_chip(pxa_last_gpio);