linux/drivers/regulator/of_regulator.c
Mark Brown 45fa2038cf regulator: of: Don't flag voltage change as possible for exact voltages
Flagging voltage changes as possible for exactly specified voltages
appears to be triggering bugs in the SDHCI code (it should be able to
handle the case where only one voltage it wants is in the range it is
allowed to set) so make sure we only set the flag in cases where there's
genuine variability.

Signed-off-by: Mark Brown <broonie@kernel.org>
2016-03-30 08:26:09 -07:00

353 lines
9.7 KiB
C

/*
* OF helpers for regulator framework
*
* Copyright (C) 2011 Texas Instruments, Inc.
* Rajendra Nayak <rnayak@ti.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*/
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/of.h>
#include <linux/regulator/machine.h>
#include <linux/regulator/driver.h>
#include <linux/regulator/of_regulator.h>
#include "internal.h"
static const char *const regulator_states[PM_SUSPEND_MAX + 1] = {
[PM_SUSPEND_MEM] = "regulator-state-mem",
[PM_SUSPEND_MAX] = "regulator-state-disk",
};
static void of_get_regulation_constraints(struct device_node *np,
struct regulator_init_data **init_data,
const struct regulator_desc *desc)
{
struct regulation_constraints *constraints = &(*init_data)->constraints;
struct regulator_state *suspend_state;
struct device_node *suspend_np;
int ret, i;
u32 pval;
constraints->name = of_get_property(np, "regulator-name", NULL);
if (!of_property_read_u32(np, "regulator-min-microvolt", &pval))
constraints->min_uV = pval;
if (!of_property_read_u32(np, "regulator-max-microvolt", &pval))
constraints->max_uV = pval;
/* Voltage change possible? */
if (constraints->min_uV != constraints->max_uV)
constraints->valid_ops_mask |= REGULATOR_CHANGE_VOLTAGE;
/* Do we have a voltage range, if so try to apply it? */
if (constraints->min_uV && constraints->max_uV)
constraints->apply_uV = true;
if (!of_property_read_u32(np, "regulator-microvolt-offset", &pval))
constraints->uV_offset = pval;
if (!of_property_read_u32(np, "regulator-min-microamp", &pval))
constraints->min_uA = pval;
if (!of_property_read_u32(np, "regulator-max-microamp", &pval))
constraints->max_uA = pval;
if (!of_property_read_u32(np, "regulator-input-current-limit-microamp",
&pval))
constraints->ilim_uA = pval;
/* Current change possible? */
if (constraints->min_uA != constraints->max_uA)
constraints->valid_ops_mask |= REGULATOR_CHANGE_CURRENT;
constraints->boot_on = of_property_read_bool(np, "regulator-boot-on");
constraints->always_on = of_property_read_bool(np, "regulator-always-on");
if (!constraints->always_on) /* status change should be possible. */
constraints->valid_ops_mask |= REGULATOR_CHANGE_STATUS;
constraints->pull_down = of_property_read_bool(np, "regulator-pull-down");
if (of_property_read_bool(np, "regulator-allow-bypass"))
constraints->valid_ops_mask |= REGULATOR_CHANGE_BYPASS;
if (of_property_read_bool(np, "regulator-allow-set-load"))
constraints->valid_ops_mask |= REGULATOR_CHANGE_DRMS;
ret = of_property_read_u32(np, "regulator-ramp-delay", &pval);
if (!ret) {
if (pval)
constraints->ramp_delay = pval;
else
constraints->ramp_disable = true;
}
ret = of_property_read_u32(np, "regulator-enable-ramp-delay", &pval);
if (!ret)
constraints->enable_time = pval;
constraints->soft_start = of_property_read_bool(np,
"regulator-soft-start");
ret = of_property_read_u32(np, "regulator-active-discharge", &pval);
if (!ret) {
constraints->active_discharge =
(pval) ? REGULATOR_ACTIVE_DISCHARGE_ENABLE :
REGULATOR_ACTIVE_DISCHARGE_DISABLE;
}
if (!of_property_read_u32(np, "regulator-initial-mode", &pval)) {
if (desc && desc->of_map_mode) {
ret = desc->of_map_mode(pval);
if (ret == -EINVAL)
pr_err("%s: invalid mode %u\n", np->name, pval);
else
constraints->initial_mode = ret;
} else {
pr_warn("%s: mapping for mode %d not defined\n",
np->name, pval);
}
}
if (!of_property_read_u32(np, "regulator-system-load", &pval))
constraints->system_load = pval;
constraints->over_current_protection = of_property_read_bool(np,
"regulator-over-current-protection");
for (i = 0; i < ARRAY_SIZE(regulator_states); i++) {
switch (i) {
case PM_SUSPEND_MEM:
suspend_state = &constraints->state_mem;
break;
case PM_SUSPEND_MAX:
suspend_state = &constraints->state_disk;
break;
case PM_SUSPEND_ON:
case PM_SUSPEND_FREEZE:
case PM_SUSPEND_STANDBY:
default:
continue;
}
suspend_np = of_get_child_by_name(np, regulator_states[i]);
if (!suspend_np || !suspend_state)
continue;
if (!of_property_read_u32(suspend_np, "regulator-mode",
&pval)) {
if (desc && desc->of_map_mode) {
ret = desc->of_map_mode(pval);
if (ret == -EINVAL)
pr_err("%s: invalid mode %u\n",
np->name, pval);
else
suspend_state->mode = ret;
} else {
pr_warn("%s: mapping for mode %d not defined\n",
np->name, pval);
}
}
if (of_property_read_bool(suspend_np,
"regulator-on-in-suspend"))
suspend_state->enabled = true;
else if (of_property_read_bool(suspend_np,
"regulator-off-in-suspend"))
suspend_state->disabled = true;
if (!of_property_read_u32(suspend_np,
"regulator-suspend-microvolt", &pval))
suspend_state->uV = pval;
of_node_put(suspend_np);
suspend_state = NULL;
suspend_np = NULL;
}
}
/**
* of_get_regulator_init_data - extract regulator_init_data structure info
* @dev: device requesting for regulator_init_data
* @node: regulator device node
* @desc: regulator description
*
* Populates regulator_init_data structure by extracting data from device
* tree node, returns a pointer to the populated struture or NULL if memory
* alloc fails.
*/
struct regulator_init_data *of_get_regulator_init_data(struct device *dev,
struct device_node *node,
const struct regulator_desc *desc)
{
struct regulator_init_data *init_data;
if (!node)
return NULL;
init_data = devm_kzalloc(dev, sizeof(*init_data), GFP_KERNEL);
if (!init_data)
return NULL; /* Out of memory? */
of_get_regulation_constraints(node, &init_data, desc);
return init_data;
}
EXPORT_SYMBOL_GPL(of_get_regulator_init_data);
struct devm_of_regulator_matches {
struct of_regulator_match *matches;
unsigned int num_matches;
};
static void devm_of_regulator_put_matches(struct device *dev, void *res)
{
struct devm_of_regulator_matches *devm_matches = res;
int i;
for (i = 0; i < devm_matches->num_matches; i++)
of_node_put(devm_matches->matches[i].of_node);
}
/**
* of_regulator_match - extract multiple regulator init data from device tree.
* @dev: device requesting the data
* @node: parent device node of the regulators
* @matches: match table for the regulators
* @num_matches: number of entries in match table
*
* This function uses a match table specified by the regulator driver to
* parse regulator init data from the device tree. @node is expected to
* contain a set of child nodes, each providing the init data for one
* regulator. The data parsed from a child node will be matched to a regulator
* based on either the deprecated property regulator-compatible if present,
* or otherwise the child node's name. Note that the match table is modified
* in place and an additional of_node reference is taken for each matched
* regulator.
*
* Returns the number of matches found or a negative error code on failure.
*/
int of_regulator_match(struct device *dev, struct device_node *node,
struct of_regulator_match *matches,
unsigned int num_matches)
{
unsigned int count = 0;
unsigned int i;
const char *name;
struct device_node *child;
struct devm_of_regulator_matches *devm_matches;
if (!dev || !node)
return -EINVAL;
devm_matches = devres_alloc(devm_of_regulator_put_matches,
sizeof(struct devm_of_regulator_matches),
GFP_KERNEL);
if (!devm_matches)
return -ENOMEM;
devm_matches->matches = matches;
devm_matches->num_matches = num_matches;
devres_add(dev, devm_matches);
for (i = 0; i < num_matches; i++) {
struct of_regulator_match *match = &matches[i];
match->init_data = NULL;
match->of_node = NULL;
}
for_each_child_of_node(node, child) {
name = of_get_property(child,
"regulator-compatible", NULL);
if (!name)
name = child->name;
for (i = 0; i < num_matches; i++) {
struct of_regulator_match *match = &matches[i];
if (match->of_node)
continue;
if (strcmp(match->name, name))
continue;
match->init_data =
of_get_regulator_init_data(dev, child,
match->desc);
if (!match->init_data) {
dev_err(dev,
"failed to parse DT for regulator %s\n",
child->name);
return -EINVAL;
}
match->of_node = of_node_get(child);
count++;
break;
}
}
return count;
}
EXPORT_SYMBOL_GPL(of_regulator_match);
struct regulator_init_data *regulator_of_get_init_data(struct device *dev,
const struct regulator_desc *desc,
struct regulator_config *config,
struct device_node **node)
{
struct device_node *search, *child;
struct regulator_init_data *init_data = NULL;
const char *name;
if (!dev->of_node || !desc->of_match)
return NULL;
if (desc->regulators_node)
search = of_get_child_by_name(dev->of_node,
desc->regulators_node);
else
search = dev->of_node;
if (!search) {
dev_dbg(dev, "Failed to find regulator container node '%s'\n",
desc->regulators_node);
return NULL;
}
for_each_available_child_of_node(search, child) {
name = of_get_property(child, "regulator-compatible", NULL);
if (!name)
name = child->name;
if (strcmp(desc->of_match, name))
continue;
init_data = of_get_regulator_init_data(dev, child, desc);
if (!init_data) {
dev_err(dev,
"failed to parse DT for regulator %s\n",
child->name);
break;
}
if (desc->of_parse_cb) {
if (desc->of_parse_cb(child, desc, config)) {
dev_err(dev,
"driver callback failed to parse DT for regulator %s\n",
child->name);
init_data = NULL;
break;
}
}
of_node_get(child);
*node = child;
break;
}
of_node_put(search);
return init_data;
}