[PATCH v2 5/5] regulator: map consumer regulator based on device tree
Nayak, Rajendra
rnayak at ti.com
Tue Oct 11 18:08:53 EST 2011
>
>> + if (supply) {
>> + struct regulator_dev *r;
>> + struct device_node *node;
>> +
>> + /* first do a dt based lookup */
>> + if (dev) {
>> + node = of_get_regulator(dev, supply);
>> + if (node)
>> + list_for_each_entry(r, ®ulator_list, list)
>> + if (node == r->dev.parent->of_node)
>> + goto found;
>> }
>>
>> - if (!found) {
>> - dev_err(dev, "Failed to find supply %s\n",
>> - init_data->supply_regulator);
>> - ret = -ENODEV;
>> - goto scrub;
>> - }
>> + /* next try doing it non-dt way */
>> + list_for_each_entry(r, ®ulator_list, list)
>> + if (strcmp(rdev_get_name(r), supply) == 0)
>> + goto found;
>>
>> + dev_err(dev, "Failed to find supply %s\n", supply);
>> + ret = -ENODEV;
>> + goto scrub;
>> +
>> +found:
>
> This is all getting *really* complicated and illegible. I'm not sure
> what the best way to structure is but erroring out early looks useful.
>
How about this updated patch?
>From f4c7d2b283740382c272c7971665375067d26dbe Mon Sep 17 00:00:00 2001
From: Rajendra Nayak <rnayak at ti.com>
Date: Thu, 22 Sep 2011 17:51:10 +0530
Subject: [PATCH 5/5] 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 at 0x0 {
...
...
vmmc-supply = <®ulator1>;
vpll-supply = <®ulator1>;
};
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: Rajendra Nayak <rnayak at ti.com>
---
drivers/regulator/core.c | 91 +++++++++++++++++++++++++++++++------
include/linux/regulator/driver.h | 2 +
2 files changed, 78 insertions(+), 15 deletions(-)
Index: linux/drivers/regulator/core.c
===================================================================
--- linux.orig/drivers/regulator/core.c 2011-10-11 11:43:27.944140106 +0530
+++ linux/drivers/regulator/core.c 2011-10-11 12:25:53.540418748 +0530
@@ -25,9 +25,11 @@
#include <linux/mutex.h>
#include <linux/suspend.h>
#include <linux/delay.h>
+#include <linux/of.h>
#include <linux/regulator/consumer.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/machine.h>
+#include <linux/regulator/of_regulator.h>
#define CREATE_TRACE_POINTS
#include <trace/events/regulator.h>
@@ -131,6 +133,33 @@
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) {
+ pr_warn("%s: %s property in node %s references invalid phandle",
+ __func__, 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)
@@ -1147,6 +1176,28 @@
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, ®ulator_list, list)
+ if (node == r->dev.parent->of_node)
+ return r;
+
+ /* if not found, try doing it non-dt way */
+ list_for_each_entry(r, ®ulator_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)
@@ -1155,6 +1206,7 @@
struct regulator_map *map;
struct regulator *regulator = ERR_PTR(-ENODEV);
const char *devname = NULL;
+ struct device_node *node;
int ret;
if (id == NULL) {
@@ -1167,6 +1219,10 @@
mutex_lock(®ulator_list_mutex);
+ rdev = regulator_dev_lookup(dev, id);
+ if (rdev)
+ goto found;
+
list_for_each_entry(map, ®ulator_map_list, list) {
/* If the mapping has a device set up it must match */
if (map->dev_name &&
@@ -2579,6 +2635,7 @@
static atomic_t regulator_no = ATOMIC_INIT(0);
struct regulator_dev *rdev;
int ret, i;
+ const char *supply;
if (regulator_desc == NULL)
return ERR_PTR(-EINVAL);
@@ -2653,21 +2710,18 @@
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, ®ulator_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;
}
Index: linux/include/linux/regulator/driver.h
===================================================================
--- linux.orig/include/linux/regulator/driver.h 2011-10-11
11:43:27.936139476 +0530
+++ linux/include/linux/regulator/driver.h 2011-10-11 11:43:43.485351850 +0530
@@ -153,6 +153,7 @@
* 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.
@@ -162,6 +163,7 @@
*/
struct regulator_desc {
const char *name;
+ const char *supply_name;
int id;
unsigned n_voltages;
struct regulator_ops *ops;
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