ti-st: add device tree support

When using device tree, driver configuration data need to be read from
device node.
Add support for getting the platform data information from the device
tree information stored in the .dtb file in case it exists.

Signed-off-by: Eyal Reizer <eyalr@ti.com>
Signed-off-by: Matt Porter <mporter@linaro.org>
[rebased on 3.18-rc4]

2 files changed, 104 insertions, 10 deletions

diff --git a/drivers/misc/ti-st/st_kim.c b/drivers/misc/ti-st/st_kim.c
index 21c2337bad68..5720af147af6 100644
--- a/drivers/misc/ti-st/st_kim.c
+++ b/drivers/misc/ti-st/st_kim.c
@@ -36,7 +36,8 @@
 #include <linux/skbuff.h>
 #include <linux/ti_wilink_st.h>
 #include <linux/module.h>
-
+#include <linux/of.h>
+#include <linux/of_device.h>
 
 #define MAX_ST_DEVICES	3	/* Imagine 1 on each UART for now */
 static struct platform_device *st_kim_devices[MAX_ST_DEVICES];
@@ -44,6 +45,9 @@ static struct platform_device *st_kim_devices[MAX_ST_DEVICES];
 /**********************************************************************/
 /* internal functions */
 
+struct ti_st_plat_data	*dt_pdata;
+static struct ti_st_plat_data *get_platform_data(struct device *dev);
+
 /**
  * st_get_plat_device -
  *	function which returns the reference to the platform device
@@ -462,7 +466,12 @@ long st_kim_start(void *kim_data)
 	struct kim_data_s	*kim_gdata = (struct kim_data_s *)kim_data;
 
 	pr_info(" %s", __func__);
-	pdata = kim_gdata->kim_pdev->dev.platform_data;
+	if (kim_gdata->kim_pdev->dev.of_node) {
+		pr_debug("use device tree data");
+		pdata = dt_pdata;
+	}
+	else
+		pdata = kim_gdata->kim_pdev->dev.platform_data;
 
 	do {
 		/* platform specific enabling code here */
@@ -522,12 +531,17 @@ long st_kim_stop(void *kim_data)
 {
 	long err = 0;
 	struct kim_data_s	*kim_gdata = (struct kim_data_s *)kim_data;
-	struct ti_st_plat_data	*pdata =
-		kim_gdata->kim_pdev->dev.platform_data;
+	struct ti_st_plat_data	*pdata;
 	struct tty_struct	*tty = kim_gdata->core_data->tty;
 
 	reinit_completion(&kim_gdata->ldisc_installed);
 
+	if (kim_gdata->kim_pdev->dev.of_node) {
+		pr_debug("use device tree data");
+		pdata = dt_pdata;
+	} else
+		pdata = kim_gdata->kim_pdev->dev.platform_data;
+
 	if (tty) {	/* can be called before ldisc is installed */
 		/* Flush any pending characters in the driver and discipline. */
 		tty_ldisc_flush(tty);
@@ -715,13 +729,52 @@ static const struct file_operations list_debugfs_fops = {
  * board-*.c file
  */
 
+static const struct of_device_id kim_of_match[] = {
+{
+    .compatible = "kim",
+  },
+  {}
+};
+MODULE_DEVICE_TABLE(of, kim_of_match);
+
+static struct ti_st_plat_data *get_platform_data(struct device *dev)
+{
+	struct device_node *np = dev->of_node;
+	const u32 * dt_property;
+	int len;
+
+	dt_pdata = kzalloc(sizeof(*dt_pdata), GFP_KERNEL);
+
+	if (!dt_pdata) {
+		pr_err("Can't allocate device_tree platform data\n");
+	}
+
+	if ((dt_property = of_get_property(np, "dev_name", &len)))
+		memcpy(&dt_pdata->dev_name,dt_property,len);
+	of_property_read_u32(np, "nshutdown_gpio", (u32 *)&dt_pdata->nshutdown_gpio);
+	of_property_read_u32(np, "flow_cntrl", (u32 *)&dt_pdata->flow_cntrl);
+	of_property_read_u32(np, "baud_rate", (u32 *)&dt_pdata->baud_rate);
+
+	return dt_pdata;
+}
+
 static struct dentry *kim_debugfs_dir;
 static int kim_probe(struct platform_device *pdev)
 {
 	struct kim_data_s	*kim_gdata;
-	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
+	struct ti_st_plat_data	*pdata;
 	int err;
 
+	if (pdev->dev.of_node)
+		pdata = get_platform_data(&pdev->dev);
+	else
+		pdata = pdev->dev.platform_data;
+
+	if (pdata == NULL) {
+		dev_err(&pdev->dev, "Platform Data is missing\n");
+		return -ENXIO;
+	}
+
 	if ((pdev->id != -1) && (pdev->id < MAX_ST_DEVICES)) {
 		/* multiple devices could exist */
 		st_kim_devices[pdev->id] = pdev;
@@ -806,9 +859,15 @@ err_core_init:
 static int kim_remove(struct platform_device *pdev)
 {
 	/* free the GPIOs requested */
-	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
+	struct ti_st_plat_data	*pdata;
 	struct kim_data_s	*kim_gdata;
 
+	if (pdev->dev.of_node) {
+		pr_debug("use device tree data");
+		pdata = dt_pdata;
+	} else
+		pdata = pdev->dev.platform_data;
+
 	kim_gdata = platform_get_drvdata(pdev);
 
 	/* Free the Bluetooth/FM/GPIO
@@ -826,12 +885,24 @@ static int kim_remove(struct platform_device *pdev)
 
 	kfree(kim_gdata);
 	kim_gdata = NULL;
+	if ( dt_pdata ) {
+		kfree(dt_pdata);
+		dt_pdata = NULL;
+	}
+
 	return 0;
 }
 
 static int kim_suspend(struct platform_device *pdev, pm_message_t state)
 {
-	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
+	struct ti_st_plat_data	*pdata;
+
+	if (pdev->dev.of_node) {
+		pr_debug("use device tree data");
+		pdata = dt_pdata;
+	}
+	else
+		pdata = pdev->dev.platform_data;
 
 	if (pdata->suspend)
 		return pdata->suspend(pdev, state);
@@ -841,7 +912,14 @@ static int kim_suspend(struct platform_device *pdev, pm_message_t state)
 
 static int kim_resume(struct platform_device *pdev)
 {
-	struct ti_st_plat_data	*pdata = pdev->dev.platform_data;
+	struct ti_st_plat_data	*pdata;
+
+	if (pdev->dev.of_node) {
+		pr_debug("use device tree data");
+		pdata = dt_pdata;
+	}
+	else
+		pdata = pdev->dev.platform_data;
 
 	if (pdata->resume)
 		return pdata->resume(pdev);
@@ -859,6 +937,7 @@ static struct platform_driver kim_platform_driver = {
 	.driver = {
 		.name = "kim",
 		.owner = THIS_MODULE,
+		.of_match_table = of_match_ptr(kim_of_match),
 	},
 };
 
diff --git a/drivers/misc/ti-st/st_ll.c b/drivers/misc/ti-st/st_ll.c
index 93b4d67cc4a3..8a821f0dad91 100644
--- a/drivers/misc/ti-st/st_ll.c
+++ b/drivers/misc/ti-st/st_ll.c
@@ -26,6 +26,9 @@
 #include <linux/ti_wilink_st.h>
 
 /**********************************************************************/
+
+extern struct ti_st_plat_data	*dt_pdata;
+
 /* internal functions */
 static void send_ll_cmd(struct st_data_s *st_data,
 	unsigned char cmd)
@@ -53,7 +56,13 @@ static void ll_device_want_to_sleep(struct st_data_s *st_data)
 
 	/* communicate to platform about chip asleep */
 	kim_data = st_data->kim_data;
-	pdata = kim_data->kim_pdev->dev.platform_data;
+	if (kim_data->kim_pdev->dev.of_node) {
+		pr_debug("use device tree data");
+		pdata = dt_pdata;
+	}
+	else
+		pdata = kim_data->kim_pdev->dev.platform_data;
+
 	if (pdata->chip_asleep)
 		pdata->chip_asleep(NULL);
 }
@@ -86,7 +95,13 @@ static void ll_device_want_to_wakeup(struct st_data_s *st_data)
 
 	/* communicate to platform about chip wakeup */
 	kim_data = st_data->kim_data;
-	pdata = kim_data->kim_pdev->dev.platform_data;
+	if (kim_data->kim_pdev->dev.of_node) {
+		pr_debug("use device tree data");
+		pdata = dt_pdata;
+	}
+	else
+		pdata = kim_data->kim_pdev->dev.platform_data;
+
 	if (pdata->chip_awake)
 		pdata->chip_awake(NULL);
 }