pwm: i.MX: add devicetree support

At the same time remove platform based support. No user for
this driver has made it into mainline so far, so all we break
is out of tree stuff.
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Reviewed-by: Shawn Guo <shawn.guo@linaro.org>
Reviewed-by: Benoît Thébaudeau <benoit.thebaudeau@advansee.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>

Documentation/devicetree/bindings/pwm/imx-pwm.txt

+Freescale i.MX PWM controller
+
+Required properties:
+- compatible: should be "fsl,<soc>-pwm"
+- reg: physical base address and length of the controller's registers
+- #pwm-cells: should be 2.  The first cell specifies the per-chip index
+  of the PWM to use and the second cell is the duty cycle in nanoseconds.
+- interrupts: The interrupt for the pwm controller
+
+Example:
+
+pwm1: pwm@53fb4000 {
+	#pwm-cells = <2>;
+	compatible = "fsl,imx53-pwm", "fsl,imx27-pwm";
+	reg = <0x53fb4000 0x4000>;
+	interrupts = <61>;
+};

drivers/pwm/pwm-imx.c

@@ -16,9 +16,9 @@
 #include <linux/clk.h>
 #include <linux/io.h>
 #include <linux/pwm.h>
+#include <linux/of_device.h>
 #include <mach/hardware.h>
 
-
 /* i.MX1 and i.MX21 share the same PWM function block: */
 
 #define MX1_PWMC    0x00   /* PWM Control Register */
@@ -204,12 +204,41 @@ static struct pwm_ops imx_pwm_ops = {
 	.owner = THIS_MODULE,
 };
 
+struct imx_pwm_data {
+	int (*config)(struct pwm_chip *chip,
+		struct pwm_device *pwm, int duty_ns, int period_ns);
+	void (*set_enable)(struct pwm_chip *chip, bool enable);
+};
+
+static struct imx_pwm_data imx_pwm_data_v1 = {
+	.config = imx_pwm_config_v1,
+	.set_enable = imx_pwm_set_enable_v1,
+};
+
+static struct imx_pwm_data imx_pwm_data_v2 = {
+	.config = imx_pwm_config_v2,
+	.set_enable = imx_pwm_set_enable_v2,
+};
+
+static const struct of_device_id imx_pwm_dt_ids[] = {
+	{ .compatible = "fsl,imx1-pwm", .data = &imx_pwm_data_v1, },
+	{ .compatible = "fsl,imx27-pwm", .data = &imx_pwm_data_v2, },
+	{ /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, imx_pwm_dt_ids);
+
 static int __devinit imx_pwm_probe(struct platform_device *pdev)
 {
+	const struct of_device_id *of_id =
+			of_match_device(imx_pwm_dt_ids, &pdev->dev);
+	struct imx_pwm_data *data;
 	struct imx_chip *imx;
 	struct resource *r;
 	int ret = 0;
 
+	if (!of_id)
+		return -ENODEV;
+
 	imx = devm_kzalloc(&pdev->dev, sizeof(*imx), GFP_KERNEL);
 	if (imx == NULL) {
 		dev_err(&pdev->dev, "failed to allocate memory\n");
@@ -236,13 +265,9 @@ static int __devinit imx_pwm_probe(struct platform_device *pdev)
 	if (imx->mmio_base == NULL)
 		return -EADDRNOTAVAIL;
 
-	if (cpu_is_mx1() || cpu_is_mx21()) {
-		imx->config = imx_pwm_config_v1;
-		imx->set_enable = imx_pwm_set_enable_v1;
-	} else {
-		imx->config = imx_pwm_config_v2;
-		imx->set_enable = imx_pwm_set_enable_v2;
-	}
+	data = of_id->data;
+	imx->config = data->config;
+	imx->set_enable = data->set_enable;
 
 	ret = pwmchip_add(&imx->chip);
 	if (ret < 0)
@@ -265,7 +290,8 @@ static int __devexit imx_pwm_remove(struct platform_device *pdev)
 
 static struct platform_driver imx_pwm_driver = {
 	.driver		= {
-		.name	= "mxc_pwm",
+		.name	= "imx-pwm",
+		.of_match_table = of_match_ptr(imx_pwm_dt_ids),
 	},
 	.probe		= imx_pwm_probe,
 	.remove		= __devexit_p(imx_pwm_remove),