Commit 69511a45 authored by Rajendra Nayak's avatar Rajendra Nayak Committed by Mark Brown
Browse files

regulator: map consumer regulator based on device tree 



Device nodes in DT can associate themselves with one or more
regulators/supply by providing a list of phandles (to regulator nodes)
and corresponding supply names.

For Example:
	devicenode: node@0x0 {
		...
		...
		vmmc-supply = <&regulator1>;
		vpll-supply = <&regulator2>;
	};

The driver would then do a regulator_get(dev, "vmmc"); to get
regulator1 and do a regulator_get(dev, "vpll"); to get
regulator2.

of_get_regulator() extracts the regulator node for a given
device, based on the supply name.

Use it to look up the regulator for a given consumer from device tree, during
a regulator_get(). If not found fallback and lookup through
the regulator_map_list instead.

Also, since the regulator dt nodes can use the same binding to
associate with a parent regulator/supply, allow the drivers to
specify a supply_name, which can then be used to lookup dt
to find the parent phandle.

Signed-off-by: default avatarRajendra Nayak <rnayak@ti.com>
Acked-by: default avatarGrant Likely <grant.likely@secretlab.ca>
Signed-off-by: default avatarMark Brown <broonie@opensource.wolfsonmicro.com>
parent 2c043bcb

drivers/regulator/core.c

+67 −12
Original line number Diff line number Diff line
@@ -25,6 +25,8 @@ 
#include <linux/mutex.h>

#include <linux/suspend.h>

#include <linux/delay.h>

#include <linux/of.h>

#include <linux/regulator/of_regulator.h>

#include <linux/regulator/consumer.h>

#include <linux/regulator/driver.h>

#include <linux/regulator/machine.h>
@@ -132,6 +134,33 @@ static struct regulator *get_device_regulator(struct device *dev) 
	return NULL;

}



/**

 * of_get_regulator - get a regulator device node based on supply name

 * @dev: Device pointer for the consumer (of regulator) device

 * @supply: regulator supply name

 *

 * Extract the regulator device node corresponding to the supply name.

 * retruns the device node corresponding to the regulator if found, else

 * returns NULL.

 */

static struct device_node *of_get_regulator(struct device *dev, const char *supply)

{

	struct device_node *regnode = NULL;

	char prop_name[32]; /* 32 is max size of property name */



	dev_dbg(dev, "Looking up %s-supply from device tree\n", supply);



	snprintf(prop_name, 32, "%s-supply", supply);

	regnode = of_parse_phandle(dev->of_node, prop_name, 0);



	if (!regnode) {

		dev_warn(dev, "%s property in node %s references invalid phandle",

				prop_name, dev->of_node->full_name);

		return NULL;

	}

	return regnode;

}



/* Platform voltage constraint check */

static int regulator_check_voltage(struct regulator_dev *rdev,

				   int *min_uV, int *max_uV)
@@ -1148,6 +1177,30 @@ static int _regulator_get_enable_time(struct regulator_dev *rdev) 
	return rdev->desc->ops->enable_time(rdev);

}



static struct regulator_dev *regulator_dev_lookup(struct device *dev,

							 const char *supply)

{

	struct regulator_dev *r;

	struct device_node *node;



	/* first do a dt based lookup */

	if (dev && dev->of_node) {

		node = of_get_regulator(dev, supply);

		if (node)

			list_for_each_entry(r, &regulator_list, list)

				if (r->dev.parent &&

					node == r->dev.of_node)

					return r;

	}



	/* if not found, try doing it non-dt way */

	list_for_each_entry(r, &regulator_list, list)

		if (strcmp(rdev_get_name(r), supply) == 0)

			return r;



	return NULL;

}



/* Internal regulator request function */

static struct regulator *_regulator_get(struct device *dev, const char *id,

					int exclusive)
@@ -1168,6 +1221,10 @@ static struct regulator *_regulator_get(struct device *dev, const char *id, 


	mutex_lock(&regulator_list_mutex);



	rdev = regulator_dev_lookup(dev, id);

	if (rdev)

		goto found;



	list_for_each_entry(map, &regulator_map_list, list) {

		/* If the mapping has a device set up it must match */

		if (map->dev_name &&
@@ -2642,6 +2699,7 @@ struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc, 
	static atomic_t regulator_no = ATOMIC_INIT(0);

	struct regulator_dev *rdev;

	int ret, i;

	const char *supply = NULL;



	if (regulator_desc == NULL)

		return ERR_PTR(-EINVAL);
@@ -2718,21 +2776,18 @@ struct regulator_dev *regulator_register(struct regulator_desc *regulator_desc, 
	if (ret < 0)

		goto scrub;



	if (init_data->supply_regulator) {

	if (init_data->supply_regulator)

		supply = init_data->supply_regulator;

	else if (regulator_desc->supply_name)

		supply = regulator_desc->supply_name;



	if (supply) {

		struct regulator_dev *r;

		int found = 0;



		list_for_each_entry(r, &regulator_list, list) {

			if (strcmp(rdev_get_name(r),

				   init_data->supply_regulator) == 0) {

				found = 1;

				break;

			}

		}

		r = regulator_dev_lookup(dev, supply);



		if (!found) {

			dev_err(dev, "Failed to find supply %s\n",

				init_data->supply_regulator);

		if (!r) {

			dev_err(dev, "Failed to find supply %s\n", supply);

			ret = -ENODEV;

			goto scrub;

		}

include/linux/regulator/driver.h

+2 −0
Original line number Diff line number Diff line
@@ -154,6 +154,7 @@ enum regulator_type { 
 * this type.

 *

 * @name: Identifying name for the regulator.

 * @supply_name: Identifying the regulator supply

 * @id: Numerical identifier for the regulator.

 * @n_voltages: Number of selectors available for ops.list_voltage().

 * @ops: Regulator operations table.
@@ -163,6 +164,7 @@ enum regulator_type { 
 */

struct regulator_desc {

	const char *name;

	const char *supply_name;

	int id;

	unsigned n_voltages;

	struct regulator_ops *ops;

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