OMAP: omap_device: Add a method to build an omap_device from a DT node

Split the omap_device_build_ss into two smaller functions that will allow to populate a platform_device already alocated by device-tree.
The functionality of the omap_device_build_ss is still the same, but the omap_device_alloc will be usable with devices already built by device-tree.

Signed-off-by Benoit Cousson <[email protected]>

Cc Kevin Hilman <[email protected]>

---
 arch/arm/plat-omap/omap_device.c |  168 ++++++++++++++++++++++++++------------
 1 files changed, 114 insertions(+), 54 deletions(-)

arch/arm/plat-omap/omap_device.c +37 -0

index f2149be..752d72a 100644
@@ -96,6 +96,11 @@
 
 static int omap_device_register(struct platform_device *pdev);
 static int omap_early_device_register(struct platform_device *pdev);
+static struct omap_device *omap_device_alloc(struct platform_device *pdev,
+				      struct omap_hwmod **ohs, int oh_cnt,
+				      struct omap_device_pm_latency *pm_lats,
+				      int pm_lats_cnt);
+
 
 static struct omap_device_pm_latency omap_default_latency[] = {
 	{

@@ -397,6 +402,105 @@ static int omap_device_fill_resources(struct omap_device *od,
 }
 
 /**
+ * omap_device_alloc - allocate an omap_device
+ * @pdev: platform_device that will be represent this omap_device
+ * @oh: ptr to the single omap_hwmod that backs this omap_device
+ * @pdata: platform_data ptr to associate with the platform_device
+ * @pdata_len: amount of memory pointed to by @pdata
+ * @pm_lats: pointer to a omap_device_pm_latency array for this device
+ * @pm_lats_cnt: ARRAY_SIZE() of @pm_lats
+ *
+ * Convenience function for allocating an omap_device structure and filling
+ * hwmods, resources and pm_latency attributes.
+ *
+ * Returns an struct omap_device pointer or ERR_PTR() on error;
+ */
+static struct omap_device *omap_device_alloc(struct platform_device *pdev,
+					struct omap_hwmod **ohs, int oh_cnt,
+					struct omap_device_pm_latency *pm_lats,
+					int pm_lats_cnt)
+{
+	int ret = -ENOMEM;
+	struct omap_device *od;
+	struct resource *res = NULL;
+	int i, res_count;
+	struct omap_hwmod **hwmods;
+
+	od = kzalloc(sizeof(struct omap_device), GFP_KERNEL);
+	if (!od) {
+		ret = -ENOMEM;
+		goto oda_exit1;
+	}
+	od->hwmods_cnt = oh_cnt;
+
+	hwmods = kzalloc(sizeof(struct omap_hwmod *) * oh_cnt,

arch/arm/plat-omap/omap_device.c +39 -0

+	 */
+	res_count = omap_device_count_resources(od);
+	if (res_count > 0) {
+		dev_dbg(&pdev->dev, "%s(): ressources allocated from hwmod %d\n",
+			__func__, res_count);
+		res = kzalloc(sizeof(struct resource) * res_count, GFP_KERNEL);
+		if (!res)
+			goto oda_exit3;
+
+		omap_device_fill_resources(od, res);
+
+		ret = platform_device_add_resources(pdev, res, res_count);
+		kfree(res);
+
+		if (ret)
+			goto oda_exit3;
+	}
+
+	if (pm_lats) {
+		od->pm_lats = pm_lats;
+		od->pm_lats_cnt = pm_lats_cnt;
+	} else {
+		od->pm_lats = omap_default_latency;
+		od->pm_lats_cnt = ARRAY_SIZE(omap_default_latency);
+	}
+
+	pdev->archdata.od = od;
+
+	for (i = 0; i < oh_cnt; i++) {
+		hwmods[i]->od = od;
+		_add_hwmod_clocks_clkdev(od, hwmods[i]);
+	}
+
+	return od;
+
+oda_exit3:
+	kfree(hwmods);
+oda_exit2:
+	kfree(od);

arch/arm/plat-omap/omap_device.c +3 -3

+}
+
+/**
  * omap_device_build - build and register an omap_device with one omap_hwmod
  * @pdev_name: name of the platform_device driver to use
  * @pdev_id: this platform_device's connection ID

@@ -455,9 +559,6 @@ struct platform_device *omap_device_build_ss(const char *pdev_name, int pdev_id,
 	int ret = -ENOMEM;
 	struct platform_device *pdev;
 	struct omap_device *od;
-	struct resource *res = NULL;
-	int i, res_count;
-	struct omap_hwmod **hwmods;
 
 	if (!ohs || oh_cnt == 0 || !pdev_name)
 		return ERR_PTR(-EINVAL);

arch/arm/plat-omap/omap_device.c +4 -46

-	od = kzalloc(sizeof(struct omap_device), GFP_KERNEL);
-	if (!od) {
-		ret = -ENOMEM;
+	od = omap_device_alloc(pdev, ohs, oh_cnt, pm_lats, pm_lats_cnt);
+	if (!od)
 		goto odbs_exit1;
-	}
-	od->hwmods_cnt = oh_cnt;
-
-	hwmods = kzalloc(sizeof(struct omap_hwmod *) * oh_cnt,
-			 GFP_KERNEL);
-	if (!hwmods)
-		goto odbs_exit2;
-
-	memcpy(hwmods, ohs, sizeof(struct omap_hwmod *) * oh_cnt);
-	od->hwmods = hwmods;
-	od->pdev = pdev;
-
-	res_count = omap_device_count_resources(od);
-	if (res_count > 0) {
-		res = kzalloc(sizeof(struct resource) * res_count, GFP_KERNEL);
-		if (!res)
-			goto odbs_exit3;
-
-		omap_device_fill_resources(od, res);
-
-		ret = platform_device_add_resources(pdev, res, res_count);
-		kfree(res);
-
-		if (ret)
-			goto odbs_exit3;
-	}
 
 	ret = platform_device_add_data(pdev, pdata, pdata_len);
 	if (ret)
-		goto odbs_exit3;
-
-	pdev->archdata.od = od;
+		goto odbs_exit2;
 
 	if (is_early_device)
 		ret = omap_early_device_register(pdev);
 	else
 		ret = omap_device_register(pdev);
 	if (ret)
-		goto odbs_exit3;
-
-	if (pm_lats) {
-		od->pm_lats = pm_lats;
-		od->pm_lats_cnt = pm_lats_cnt;
-	} else {
-		od->pm_lats = omap_default_latency;
-		od->pm_lats_cnt = ARRAY_SIZE(omap_default_latency);
-	}
-
-	for (i = 0; i < oh_cnt; i++) {
-		hwmods[i]->od = od;
-		_add_hwmod_clocks_clkdev(od, hwmods[i]);
-	}
+		goto odbs_exit2;
 

Quoted 6 lines · Benoit Cousson

Split the omap_device_build_ss into two smaller functions that will allow to populate a platform_device already alocated by device-tree.
The functionality of the omap_device_build_ss is still the same, but the omap_device_alloc will be usable with devices already built by device-tree.

Very nice, I started down this path in the original series, but didn't finish.
Some minor comments below...

Quoted 62 lines

Signed-off-by Benoit Cousson<[email protected]>

Cc Kevin Hilman<[email protected]>

---
  arch/arm/plat-omap/omap_device.c |  168 ++++++++++++++++++++++++++------------
  1 files changed, 114 insertions(+), 54 deletions(-)

arch/arm/plat-omap/omap_device.c +41 -0

index f2149be..752d72a 100644
@@ -96,6 +96,11 @@
 
  static int omap_device_register(struct platform_device *pdev);
  static int omap_early_device_register(struct platform_device *pdev);
+static struct omap_device *omap_device_alloc(struct platform_device *pdev,
+				      struct omap_hwmod **ohs, int oh_cnt,
+				      struct omap_device_pm_latency *pm_lats,
+				      int pm_lats_cnt);
+
 
  static struct omap_device_pm_latency omap_default_latency[] = {
  	{

@@ -397,6 +402,105 @@ static int omap_device_fill_resources(struct omap_device *od,
  }
 
  /**
+ * omap_device_alloc - allocate an omap_device
+ * @pdev: platform_device that will be represent this omap_device
+ * @oh: ptr to the single omap_hwmod that backs this omap_device
+ * @pdata: platform_data ptr to associate with the platform_device
+ * @pdata_len: amount of memory pointed to by @pdata
+ * @pm_lats: pointer to a omap_device_pm_latency array for this device
+ * @pm_lats_cnt: ARRAY_SIZE() of @pm_lats
+ *
+ * Convenience function for allocating an omap_device structure and filling
+ * hwmods, resources and pm_latency attributes.
+ *
+ * Returns an struct omap_device pointer or ERR_PTR() on error;
+ */
+static struct omap_device *omap_device_alloc(struct platform_device *pdev,
+					struct omap_hwmod **ohs, int oh_cnt,
+					struct omap_device_pm_latency *pm_lats,
+					int pm_lats_cnt)
+{
+	int ret = -ENOMEM;
+	struct omap_device *od;
+	struct resource *res = NULL;
+	int i, res_count;
+	struct omap_hwmod **hwmods;
+
+	od = kzalloc(sizeof(struct omap_device), GFP_KERNEL);
+	if (!od) {
+		ret = -ENOMEM;
+		goto oda_exit1;
+	}
+	od->hwmods_cnt = oh_cnt;
+
+	hwmods = kzalloc(sizeof(struct omap_hwmod *) * oh_cnt,
+			 GFP_KERNEL);
+	if (!hwmods)
+		goto oda_exit2;
+

arch/arm/plat-omap/omap_device.c static int omap_device_fill_resources(struct omap_device *od, · line 446

Quoted 6 lines

arch/arm/plat-omap/omap_device.c +6 -0

+	memcpy(hwmods, ohs, sizeof(struct omap_hwmod *) * oh_cnt);
+	od->hwmods = hwmods;
+	od->pdev = pdev;
+
+	if (pdev->num_resources&&  pdev->resource)
+		dev_warn(&pdev->dev, "%s(): ressources already allocated %d\n",

typo: ressources (occurs again below)

also, this check/warn should probably go after the 'HACK' comment below.

arch/arm/plat-omap/omap_device.c static int omap_device_fill_resources(struct omap_device *od, · line 449

Quoted 4 lines

arch/arm/plat-omap/omap_device.c +3 -0

+			__func__, pdev->num_resources);
+	/*
+	 * HACK: Idealy the resources from DT should match, and hwmod

s/Idealy/Ideally/

arch/arm/plat-omap/omap_device.c static int omap_device_fill_resources(struct omap_device *od, · line 451

Quoted 3 lines

arch/arm/plat-omap/omap_device.c +2 -0

+	 * should just add the missing ones. Since the name is not
+	 * properly populated by DT, stick to hwmod resources only.

I think this limitation is fine until we come to resolution in the named resources debate.

Quoted 43 lines

arch/arm/plat-omap/omap_device.c +43 -0

+	 */
+	res_count = omap_device_count_resources(od);
+	if (res_count>  0) {
+		dev_dbg(&pdev->dev, "%s(): ressources allocated from hwmod %d\n",
+			__func__, res_count);
+		res = kzalloc(sizeof(struct resource) * res_count, GFP_KERNEL);
+		if (!res)
+			goto oda_exit3;
+
+		omap_device_fill_resources(od, res);
+
+		ret = platform_device_add_resources(pdev, res, res_count);
+		kfree(res);
+
+		if (ret)
+			goto oda_exit3;
+	}
+
+	if (pm_lats) {
+		od->pm_lats = pm_lats;
+		od->pm_lats_cnt = pm_lats_cnt;
+	} else {
+		od->pm_lats = omap_default_latency;
+		od->pm_lats_cnt = ARRAY_SIZE(omap_default_latency);
+	}
+
+	pdev->archdata.od = od;
+
+	for (i = 0; i<  oh_cnt; i++) {
+		hwmods[i]->od = od;
+		_add_hwmod_clocks_clkdev(od, hwmods[i]);
+	}
+
+	return od;
+
+oda_exit3:
+	kfree(hwmods);
+oda_exit2:
+	kfree(od);
+oda_exit1:
+	dev_err(&pdev->dev, "omap_device: build failed (%d)\n", ret);
+
+	return ERR_PTR(ret);

arch/arm/plat-omap/omap_device.c static int omap_device_fill_resources(struct omap_device *od, · line 500

Quoted 6 lines

arch/arm/plat-omap/omap_device.c +6 -0

+}
+
+void omap_device_delete(struct omap_device *od)
+{
+	kfree(od->hwmods);
+	kfree(od);

maybe set pdev->archdata.od = NULL too.

Quoted 20 lines

arch/arm/plat-omap/omap_device.c +3 -3

+}
+
+/**
   * omap_device_build - build and register an omap_device with one omap_hwmod
   * @pdev_name: name of the platform_device driver to use
   * @pdev_id: this platform_device's connection ID

@@ -455,9 +559,6 @@ struct platform_device *omap_device_build_ss(const char *pdev_name, int pdev_id,
  	int ret = -ENOMEM;
  	struct platform_device *pdev;
  	struct omap_device *od;
-	struct resource *res = NULL;
-	int i, res_count;
-	struct omap_hwmod **hwmods;
 
  	if (!ohs || oh_cnt == 0 || !pdev_name)
  		return ERR_PTR(-EINVAL);

@@ -471,72 +572,31 @@ struct platform_device *omap_device_build_ss(const char *pdev_name, int pdev_id,
  		goto odbs_exit;
  	}
 

arch/arm/plat-omap/omap_device.c struct platform_device *omap_device_build_ss(const char *pdev_name, int pdev_id, · line 579

Quoted 7 lines

arch/arm/plat-omap/omap_device.c +5 -2

-	pr_debug("omap_device: %s: building with %d hwmods\n", pdev_name,
-		 oh_cnt);
+	/* Set the dev_name early to allow dev_xxx in omap_device_alloc */
+	if (pdev->id != -1)
+		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
+	else
+		dev_set_name(&pdev->dev, "%s", pdev->name);

Minor: I think setting dev->init_name is more appropriate here, and should have the same effect.

Quoted 4 lines

Quoted 4 lines

arch/arm/plat-omap/omap_device.c +0 -0

@@ -471,72 +572,31 @@ struct platform_device *omap_device_build_ss(const char *pdev_name, int pdev_id,
  		goto odbs_exit;
  	}
 

Quoted 10 lines

arch/arm/plat-omap/omap_device.c struct platform_device *omap_device_build_ss(const char *pdev_name, int pdev_id, · line 579

Quoted 7 lines

arch/arm/plat-omap/omap_device.c +5 -2

-	pr_debug("omap_device: %s: building with %d hwmods\n", pdev_name,
-		 oh_cnt);
+	/* Set the dev_name early to allow dev_xxx in omap_device_alloc */
+	if (pdev->id != -1)
+		dev_set_name(&pdev->dev, "%s.%d", pdev->name,  pdev->id);
+	else
+		dev_set_name(&pdev->dev, "%s", pdev->name);

Minor: I think setting dev->init_name is more appropriate here, and should have the same effect.

The slight difference is that if I do that:
pdev->dev.init_name = kasprintf(GFP_KERNEL, "%s.%d", pdev->name, pdev->id);

I will have to free it myself, because device_add is doing only that:

        if (dev->init_name) {
                dev_set_name(dev, "%s", dev->init_name);
                dev->init_name = NULL;
        }

Whereas dev_set_name is doing it for me.

So it will add one more line later. Does it worth it?

Add two helpers function to parse a property that contains multiple strings.

These functions might be exported and moved to a common place if they can to be useful elsewhere.

Signed-off-by Benoit Cousson <[email protected]>

Cc Kevin Hilman <[email protected]>

---
 arch/arm/plat-omap/omap_device.c |   39 ++++++++++++++++++++++++++++++++++++++
 1 files changed, 39 insertions(+), 0 deletions(-)

arch/arm/plat-omap/omap_device.c +39 -0

index 752d72a..70361f8 100644
@@ -315,6 +315,45 @@ static void _add_hwmod_clocks_clkdev(struct omap_device *od,
 		_add_clkdev(od, oh->opt_clks[i].role, oh->opt_clks[i].clk);
 }
 
+/*
+ * XXX: DT helper functions that should probably move elsewhere if
+ * they become usefull for other needs.
+ */
+static int _dt_count_property_string(const char *prop, int len)
+{
+	int i = 0;
+	size_t l = 0, total = 0;
+
+	if (!prop || !len)
+		return -EINVAL;
+
+	for (i = 0; len >= total; total += l, prop += l) {
+		l = strlen(prop) + 1;
+		if (*prop != 0)
+			i++;
+	}
+	return i;
+}
+
+static int _dt_get_property(const char *prop, int len, int index, char *output,
+			    int size)
+{
+	int i = 0;
+	size_t l = 0, total = 0;
+
+	if (!prop || !len)
+		return -EINVAL;
+
+	for (i = 0; len >= total; total += l, prop += l) {
+		l = strlcpy(output, prop, size) + 1;
+		if (*prop != 0) {
+			if (i++ == index)
+				return 0;
+		}
+	}
+	return -ENODEV;
+}
+
 
 /* Public functions for use by core code */

Quoted 3 lines · Benoit Cousson

Add two helpers function to parse a property that contains multiple strings.

Quoted 5 lines

These functions might be exported and moved to a common place if they can to be useful elsewhere.

Signed-off-by Benoit Cousson<[email protected]>

Cc Kevin Hilman<[email protected]>

These should just be folded into 3/3 where they are used (with a comment changelog of course.)

Kevin

Quoted 53 lines

---
  arch/arm/plat-omap/omap_device.c |   39 ++++++++++++++++++++++++++++++++++++++
  1 files changed, 39 insertions(+), 0 deletions(-)

arch/arm/plat-omap/omap_device.c +39 -0

index 752d72a..70361f8 100644
@@ -315,6 +315,45 @@ static void _add_hwmod_clocks_clkdev(struct omap_device *od,
  		_add_clkdev(od, oh->opt_clks[i].role, oh->opt_clks[i].clk);
  }
 
+/*
+ * XXX: DT helper functions that should probably move elsewhere if
+ * they become usefull for other needs.
+ */
+static int _dt_count_property_string(const char *prop, int len)
+{
+	int i = 0;
+	size_t l = 0, total = 0;
+
+	if (!prop || !len)
+		return -EINVAL;
+
+	for (i = 0; len>= total; total += l, prop += l) {
+		l = strlen(prop) + 1;
+		if (*prop != 0)
+			i++;
+	}
+	return i;
+}
+
+static int _dt_get_property(const char *prop, int len, int index, char *output,
+			    int size)
+{
+	int i = 0;
+	size_t l = 0, total = 0;
+
+	if (!prop || !len)
+		return -EINVAL;
+
+	for (i = 0; len>= total; total += l, prop += l) {
+		l = strlcpy(output, prop, size) + 1;
+		if (*prop != 0) {
+			if (i++ == index)
+				return 0;
+		}
+	}
+	return -ENODEV;
+}
+
 
  /* Public functions for use by core code */

Add a notifier called during device_add phase. If a of_node is present, retrieve the hwmod entry in order to populate propely the omap_device

structure.
For the moment the resource from the device-tree are overloaded. DT does not support named resource yet, and thus, most driver will not work without that information.

Signed-off-by Benoit Cousson<[email protected]>

Cc Kevin Hilman<[email protected]>

---
  arch/arm/plat-omap/omap_device.c |  102 ++++++++++++++++++++++++++++++++++++++
  1 files changed, 102 insertions(+), 0 deletions(-)

arch/arm/plat-omap/omap_device.c +0 -0

index 70361f8..0ae9e7f 100644

arch/arm/plat-omap/omap_device.c +101 -0

+#include<linux/notifier.h>
 
  #include<plat/omap_device.h>
  #include<plat/omap_hwmod.h>

@@ -94,6 +96,8 @@
  #define USE_WAKEUP_LAT			0
  #define IGNORE_WAKEUP_LAT		1
 
+#define MAX_HWMOD_NAME_SIZE		32
+
  static int omap_device_register(struct platform_device *pdev);
  static int omap_early_device_register(struct platform_device *pdev);
  static struct omap_device *omap_device_alloc(struct platform_device *pdev,

@@ -354,6 +358,100 @@ static int _dt_get_property(const char *prop, int len, int index, char *output,
  	return -ENODEV;
  }
 
+static struct dev_pm_domain omap_device_pm_domain;
+
+/**
+ * omap_device_build_from_dt - build an omap_device with multiple hwmods
+ * @pdev_name: name of the platform_device driver to use
+ * @pdev_id: this platform_device's connection ID
+ * @oh: ptr to the single omap_hwmod that backs this omap_device
+ * @pdata: platform_data ptr to associate with the platform_device
+ * @pdata_len: amount of memory pointed to by @pdata
+ * @pm_lats: pointer to a omap_device_pm_latency array for this device
+ * @pm_lats_cnt: ARRAY_SIZE() of @pm_lats
+ * @is_early_device: should the device be registered as an early device or not
+ *
+ * Function for building an omap_device already registered from device-tree
+ *
+ * Returns 0 or PTR_ERR() on error.
+ */
+static int omap_device_build_from_dt(struct platform_device *pdev)
+{
+	struct omap_hwmod **hwmods;
+	struct omap_device *od;
+	struct omap_hwmod *oh;
+	char oh_name[MAX_HWMOD_NAME_SIZE];
+	const char *prop;
+	int oh_cnt, i, prop_len;
+	int ret = 0;
+
+	prop = of_get_property(pdev->dev.of_node, "hwmods",&prop_len);
+	oh_cnt = _dt_count_property_string(prop, prop_len);
+	if (!oh_cnt || IS_ERR_VALUE(oh_cnt)) {
+		dev_warn(&pdev->dev, "No 'hwmods' to build omap_device\n");
+		return -ENODEV;
+	}
+
+	hwmods = kzalloc(sizeof(struct omap_hwmod *) * oh_cnt, GFP_KERNEL);
+	if (!hwmods) {
+		ret = -ENOMEM;
+		goto odbfd_exit;
+	}
+
+	for (i = 0; i<  oh_cnt; i++) {
+		_dt_get_property(prop, prop_len, i, oh_name,
+				 MAX_HWMOD_NAME_SIZE);
+
+		oh = omap_hwmod_lookup(oh_name);
+		if (!oh) {
+			dev_err(&pdev->dev, "Cannot lookup hwmod '%s'\n",
+				oh_name);
+			ret = -EINVAL;
+			goto odbfd_exit1;
+		}
+		hwmods[i] = oh;
+	}
+
+	od = omap_device_alloc(pdev, hwmods, oh_cnt, NULL, 0);
+	if (!od) {
+		dev_err(&pdev->dev, "Cannot allocate omap_device for :%s\n",
+			oh_name);
+		ret = PTR_ERR(od);
+		goto odbfd_exit1;
+	}
+
+	if (of_get_property(pdev->dev.of_node, "no_idle_on_suspend", NULL))
+		omap_device_disable_idle_on_suspend(pdev);
+
+	pdev->dev.pm_domain =&omap_device_pm_domain;
+
+odbfd_exit1:
+	kfree(hwmods);
+odbfd_exit:
+	return ret;
+}
+
+static int _omap_device_notifier_call(struct notifier_block *nb,
+				      unsigned long event, void *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+
+	switch (event) {
+	case BUS_NOTIFY_ADD_DEVICE:
+		if (pdev->dev.of_node) {
+			dev_dbg(&pdev->dev, "add_device with DT bindings\n");
+			omap_device_build_from_dt(pdev);
+		}
+		break;
+
+	case BUS_NOTIFY_DEL_DEVICE:
+		dev_dbg(&pdev->dev, "del_device\n");
+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
 
  /* Public functions for use by core code */
 

@@ -1064,8 +1162,12 @@ struct device omap_device_parent = {
  	.parent         =&platform_bus,
  };
 
+static struct notifier_block platform_nb;
+
  static int __init omap_device_init(void)
  {
+	platform_nb.notifier_call = _omap_device_notifier_call;
+	bus_register_notifier(&platform_bus_type,&platform_nb);
  	return device_register(&omap_device_parent);
  }
  core_initcall(omap_device_init);

Add a notifier called during device_add phase. If a of_node is present, retrieve the hwmod entry in order to populate propely the omap_device structure.
For the moment the resource from the device-tree are overloaded. DT does not support named resource yet, and thus, most driver will not work without that information.

Signed-off-by Benoit Cousson <[email protected]>

Cc Kevin Hilman <[email protected]>

---
 arch/arm/plat-omap/omap_device.c |  102 ++++++++++++++++++++++++++++++++++++++
 1 files changed, 102 insertions(+), 0 deletions(-)

arch/arm/plat-omap/omap_device.c +82 -0

index 70361f8..0ae9e7f 100644
@@ -85,6 +85,8 @@
 #include <linux/clk.h>
 #include <linux/clkdev.h>
 #include <linux/pm_runtime.h>
+#include <linux/of_platform.h>
+#include <linux/notifier.h>
 
 #include <plat/omap_device.h>
 #include <plat/omap_hwmod.h>

@@ -94,6 +96,8 @@
 #define USE_WAKEUP_LAT			0
 #define IGNORE_WAKEUP_LAT		1
 
+#define MAX_HWMOD_NAME_SIZE		32
+
 static int omap_device_register(struct platform_device *pdev);
 static int omap_early_device_register(struct platform_device *pdev);
 static struct omap_device *omap_device_alloc(struct platform_device *pdev,

@@ -354,6 +358,100 @@ static int _dt_get_property(const char *prop, int len, int index, char *output,
 	return -ENODEV;
 }
 
+static struct dev_pm_domain omap_device_pm_domain;
+
+/**
+ * omap_device_build_from_dt - build an omap_device with multiple hwmods
+ * @pdev_name: name of the platform_device driver to use
+ * @pdev_id: this platform_device's connection ID
+ * @oh: ptr to the single omap_hwmod that backs this omap_device
+ * @pdata: platform_data ptr to associate with the platform_device
+ * @pdata_len: amount of memory pointed to by @pdata
+ * @pm_lats: pointer to a omap_device_pm_latency array for this device
+ * @pm_lats_cnt: ARRAY_SIZE() of @pm_lats
+ * @is_early_device: should the device be registered as an early device or not
+ *
+ * Function for building an omap_device already registered from device-tree
+ *
+ * Returns 0 or PTR_ERR() on error.
+ */
+static int omap_device_build_from_dt(struct platform_device *pdev)
+{
+	struct omap_hwmod **hwmods;
+	struct omap_device *od;
+	struct omap_hwmod *oh;
+	char oh_name[MAX_HWMOD_NAME_SIZE];
+	const char *prop;
+	int oh_cnt, i, prop_len;
+	int ret = 0;
+
+	prop = of_get_property(pdev->dev.of_node, "hwmods", &prop_len);
+	oh_cnt = _dt_count_property_string(prop, prop_len);
+	if (!oh_cnt || IS_ERR_VALUE(oh_cnt)) {
+		dev_warn(&pdev->dev, "No 'hwmods' to build omap_device\n");
+		return -ENODEV;
+	}
+
+	hwmods = kzalloc(sizeof(struct omap_hwmod *) * oh_cnt, GFP_KERNEL);
+	if (!hwmods) {
+		ret = -ENOMEM;
+		goto odbfd_exit;
+	}
+
+	for (i = 0; i < oh_cnt; i++) {
+		_dt_get_property(prop, prop_len, i, oh_name,
+				 MAX_HWMOD_NAME_SIZE);
+
+		oh = omap_hwmod_lookup(oh_name);
+		if (!oh) {
+			dev_err(&pdev->dev, "Cannot lookup hwmod '%s'\n",
+				oh_name);
+			ret = -EINVAL;
+			goto odbfd_exit1;
+		}
+		hwmods[i] = oh;
+	}
+
+	od = omap_device_alloc(pdev, hwmods, oh_cnt, NULL, 0);
+	if (!od) {
+		dev_err(&pdev->dev, "Cannot allocate omap_device for :%s\n",
+			oh_name);
+		ret = PTR_ERR(od);
+		goto odbfd_exit1;
+	}
+
+	if (of_get_property(pdev->dev.of_node, "no_idle_on_suspend", NULL))
+		omap_device_disable_idle_on_suspend(pdev);
+
+	pdev->dev.pm_domain = &omap_device_pm_domain;
+
+odbfd_exit1:
+	kfree(hwmods);
+odbfd_exit:
+	return ret;
+}
+
+static int _omap_device_notifier_call(struct notifier_block *nb,
+				      unsigned long event, void *dev)
+{
+	struct platform_device *pdev = to_platform_device(dev);
+

arch/arm/plat-omap/omap_device.c +10 -0

+		break;
+	}
+
+	return NOTIFY_DONE;
+}
+
 
 /* Public functions for use by core code */
 

@@ -1064,8 +1162,12 @@ struct device omap_device_parent = {
 	.parent         = &platform_bus,
 };
 
+static struct notifier_block platform_nb;
+
 static int __init omap_device_init(void)
 {
+	platform_nb.notifier_call = _omap_device_notifier_call;
+	bus_register_notifier(&platform_bus_type, &platform_nb);
 	return device_register(&omap_device_parent);
 }
 core_initcall(omap_device_init);

Quoted 9 lines · Benoit Cousson

Add a notifier called during device_add phase. If a of_node is present, retrieve the hwmod entry in order to populate propely the omap_device structure.
For the moment the resource from the device-tree are overloaded. DT does not support named resource yet, and thus, most driver will not work without that information.

Signed-off-by Benoit Cousson<[email protected]>

Cc Kevin Hilman<[email protected]>

Nice, minor comment below...

arch/arm/plat-omap/omap_device.c static int _dt_get_property(const char *prop, int len, int index, char *output, · line 448

Quoted 2 lines

arch/arm/plat-omap/omap_device.c +2 -0

+	case BUS_NOTIFY_DEL_DEVICE:
+		dev_dbg(&pdev->dev, "del_device\n");

Need a delete/cleanup here.

Looks like all all it needs to do is call omap_device_delete()?