linux/drivers/regulator/of_regulator.c
Cristian Marussi e7095c35ab
regulator: core: add of_match_full_name boolean flag
During regulators registration, if .of_match and .regulators_node are
defined as non-null strings in struct regulator_desc the core searches the
DT subtree rooted at .regulators_node trying to match, at first, .of_match
against the 'regulator-compatible' property and, then, falling back to use
the name of the node itself to determine a good match.

Property 'regulator-compatible', though, is now deprecated and falling back
to match against the node name, works fine only as long as the involved
nodes are named in an unique way across the searched subtree; if that's not
the case, like when using <common-name>@<unit> style naming for properties
indexed via 'reg' property (as advised by the standard), the above matching
mechanism based on the simple common name will lead to multiple matches and
the only viable alternative would be to properly define the now deprecated
'regulator-compatible' as the node full name, i.e. <common-name>@<unit>.

In order to address this case without using such deprecated binding, define
a new boolean flag .of_match_full_name in struct regulator_desc to force
the core to match against the node full-name instead of the plain name.

Signed-off-by: Cristian Marussi <cristian.marussi@arm.com>
Link: https://lore.kernel.org/r/20201119191051.46363-4-cristian.marussi@arm.com
Signed-off-by: Mark Brown <broonie@kernel.org>
2020-11-23 18:38:13 +00:00

638 lines
16 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* OF helpers for regulator framework
*
* Copyright (C) 2011 Texas Instruments, Inc.
* Rajendra Nayak <rnayak@ti.com>
*/
#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_STANDBY] = "regulator-state-standby",
[PM_SUSPEND_MEM] = "regulator-state-mem",
[PM_SUSPEND_MAX] = "regulator-state-disk",
};
static int of_get_regulation_constraints(struct device *dev,
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;
unsigned int mode;
int ret, i, len;
int n_phandles;
u32 pval;
n_phandles = of_count_phandle_with_args(np, "regulator-coupled-with",
NULL);
n_phandles = max(n_phandles, 0);
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-settling-time-us", &pval);
if (!ret)
constraints->settling_time = pval;
ret = of_property_read_u32(np, "regulator-settling-time-up-us", &pval);
if (!ret)
constraints->settling_time_up = pval;
if (constraints->settling_time_up && constraints->settling_time) {
pr_warn("%pOFn: ambiguous configuration for settling time, ignoring 'regulator-settling-time-up-us'\n",
np);
constraints->settling_time_up = 0;
}
ret = of_property_read_u32(np, "regulator-settling-time-down-us",
&pval);
if (!ret)
constraints->settling_time_down = pval;
if (constraints->settling_time_down && constraints->settling_time) {
pr_warn("%pOFn: ambiguous configuration for settling time, ignoring 'regulator-settling-time-down-us'\n",
np);
constraints->settling_time_down = 0;
}
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) {
mode = desc->of_map_mode(pval);
if (mode == REGULATOR_MODE_INVALID)
pr_err("%pOFn: invalid mode %u\n", np, pval);
else
constraints->initial_mode = mode;
} else {
pr_warn("%pOFn: mapping for mode %d not defined\n",
np, pval);
}
}
len = of_property_count_elems_of_size(np, "regulator-allowed-modes",
sizeof(u32));
if (len > 0) {
if (desc && desc->of_map_mode) {
for (i = 0; i < len; i++) {
ret = of_property_read_u32_index(np,
"regulator-allowed-modes", i, &pval);
if (ret) {
pr_err("%pOFn: couldn't read allowed modes index %d, ret=%d\n",
np, i, ret);
break;
}
mode = desc->of_map_mode(pval);
if (mode == REGULATOR_MODE_INVALID)
pr_err("%pOFn: invalid regulator-allowed-modes element %u\n",
np, pval);
else
constraints->valid_modes_mask |= mode;
}
if (constraints->valid_modes_mask)
constraints->valid_ops_mask
|= REGULATOR_CHANGE_MODE;
} else {
pr_warn("%pOFn: mode mapping not defined\n", np);
}
}
if (!of_property_read_u32(np, "regulator-system-load", &pval))
constraints->system_load = pval;
if (n_phandles) {
constraints->max_spread = devm_kzalloc(dev,
sizeof(*constraints->max_spread) * n_phandles,
GFP_KERNEL);
if (!constraints->max_spread)
return -ENOMEM;
of_property_read_u32_array(np, "regulator-coupled-max-spread",
constraints->max_spread, n_phandles);
}
if (!of_property_read_u32(np, "regulator-max-step-microvolt",
&pval))
constraints->max_uV_step = 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_STANDBY:
suspend_state = &constraints->state_standby;
break;
case PM_SUSPEND_ON:
case PM_SUSPEND_TO_IDLE:
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) {
mode = desc->of_map_mode(pval);
if (mode == REGULATOR_MODE_INVALID)
pr_err("%pOFn: invalid mode %u\n",
np, pval);
else
suspend_state->mode = mode;
} else {
pr_warn("%pOFn: mapping for mode %d not defined\n",
np, pval);
}
}
if (of_property_read_bool(suspend_np,
"regulator-on-in-suspend"))
suspend_state->enabled = ENABLE_IN_SUSPEND;
else if (of_property_read_bool(suspend_np,
"regulator-off-in-suspend"))
suspend_state->enabled = DISABLE_IN_SUSPEND;
if (!of_property_read_u32(suspend_np,
"regulator-suspend-min-microvolt", &pval))
suspend_state->min_uV = pval;
if (!of_property_read_u32(suspend_np,
"regulator-suspend-max-microvolt", &pval))
suspend_state->max_uV = pval;
if (!of_property_read_u32(suspend_np,
"regulator-suspend-microvolt", &pval))
suspend_state->uV = pval;
else /* otherwise use min_uV as default suspend voltage */
suspend_state->uV = suspend_state->min_uV;
if (of_property_read_bool(suspend_np,
"regulator-changeable-in-suspend"))
suspend_state->changeable = true;
if (i == PM_SUSPEND_MEM)
constraints->initial_state = PM_SUSPEND_MEM;
of_node_put(suspend_np);
suspend_state = NULL;
suspend_np = NULL;
}
return 0;
}
/**
* 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 structure 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? */
if (of_get_regulation_constraints(dev, node, &init_data, desc))
return NULL;
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 %pOFn\n",
child);
of_node_put(child);
return -EINVAL;
}
match->of_node = of_node_get(child);
count++;
break;
}
}
return count;
}
EXPORT_SYMBOL_GPL(of_regulator_match);
static struct
device_node *regulator_of_get_init_node(struct device *dev,
const struct regulator_desc *desc)
{
struct device_node *search, *child;
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 = of_node_get(dev->of_node);
if (!strcmp(desc->of_match, search->name))
return search;
}
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) {
if (!desc->of_match_full_name)
name = child->name;
else
name = child->full_name;
}
if (!strcmp(desc->of_match, name)) {
of_node_put(search);
return of_node_get(child);
}
}
of_node_put(search);
return NULL;
}
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 *child;
struct regulator_init_data *init_data = NULL;
child = regulator_of_get_init_node(dev, desc);
if (!child)
return NULL;
init_data = of_get_regulator_init_data(dev, child, desc);
if (!init_data) {
dev_err(dev, "failed to parse DT for regulator %pOFn\n", child);
goto error;
}
if (desc->of_parse_cb) {
int ret;
ret = desc->of_parse_cb(child, desc, config);
if (ret) {
if (ret == -EPROBE_DEFER) {
of_node_put(child);
return ERR_PTR(-EPROBE_DEFER);
}
dev_err(dev,
"driver callback failed to parse DT for regulator %pOFn\n",
child);
goto error;
}
}
*node = child;
return init_data;
error:
of_node_put(child);
return NULL;
}
struct regulator_dev *of_find_regulator_by_node(struct device_node *np)
{
struct device *dev;
dev = class_find_device_by_of_node(&regulator_class, np);
return dev ? dev_to_rdev(dev) : NULL;
}
/*
* Returns number of regulators coupled with rdev.
*/
int of_get_n_coupled(struct regulator_dev *rdev)
{
struct device_node *node = rdev->dev.of_node;
int n_phandles;
n_phandles = of_count_phandle_with_args(node,
"regulator-coupled-with",
NULL);
return (n_phandles > 0) ? n_phandles : 0;
}
/* Looks for "to_find" device_node in src's "regulator-coupled-with" property */
static bool of_coupling_find_node(struct device_node *src,
struct device_node *to_find,
int *index)
{
int n_phandles, i;
bool found = false;
n_phandles = of_count_phandle_with_args(src,
"regulator-coupled-with",
NULL);
for (i = 0; i < n_phandles; i++) {
struct device_node *tmp = of_parse_phandle(src,
"regulator-coupled-with", i);
if (!tmp)
break;
/* found */
if (tmp == to_find)
found = true;
of_node_put(tmp);
if (found) {
*index = i;
break;
}
}
return found;
}
/**
* of_check_coupling_data - Parse rdev's coupling properties and check data
* consistency
* @rdev: pointer to regulator_dev whose data is checked
*
* Function checks if all the following conditions are met:
* - rdev's max_spread is greater than 0
* - all coupled regulators have the same max_spread
* - all coupled regulators have the same number of regulator_dev phandles
* - all regulators are linked to each other
*
* Returns true if all conditions are met.
*/
bool of_check_coupling_data(struct regulator_dev *rdev)
{
struct device_node *node = rdev->dev.of_node;
int n_phandles = of_get_n_coupled(rdev);
struct device_node *c_node;
int index;
int i;
bool ret = true;
/* iterate over rdev's phandles */
for (i = 0; i < n_phandles; i++) {
int max_spread = rdev->constraints->max_spread[i];
int c_max_spread, c_n_phandles;
if (max_spread <= 0) {
dev_err(&rdev->dev, "max_spread value invalid\n");
return false;
}
c_node = of_parse_phandle(node,
"regulator-coupled-with", i);
if (!c_node)
ret = false;
c_n_phandles = of_count_phandle_with_args(c_node,
"regulator-coupled-with",
NULL);
if (c_n_phandles != n_phandles) {
dev_err(&rdev->dev, "number of coupled reg phandles mismatch\n");
ret = false;
goto clean;
}
if (!of_coupling_find_node(c_node, node, &index)) {
dev_err(&rdev->dev, "missing 2-way linking for coupled regulators\n");
ret = false;
goto clean;
}
if (of_property_read_u32_index(c_node, "regulator-coupled-max-spread",
index, &c_max_spread)) {
ret = false;
goto clean;
}
if (c_max_spread != max_spread) {
dev_err(&rdev->dev,
"coupled regulators max_spread mismatch\n");
ret = false;
goto clean;
}
clean:
of_node_put(c_node);
if (!ret)
break;
}
return ret;
}
/**
* of_parse_coupled regulator - Get regulator_dev pointer from rdev's property
* @rdev: Pointer to regulator_dev, whose DTS is used as a source to parse
* "regulator-coupled-with" property
* @index: Index in phandles array
*
* Returns the regulator_dev pointer parsed from DTS. If it has not been yet
* registered, returns NULL
*/
struct regulator_dev *of_parse_coupled_regulator(struct regulator_dev *rdev,
int index)
{
struct device_node *node = rdev->dev.of_node;
struct device_node *c_node;
struct regulator_dev *c_rdev;
c_node = of_parse_phandle(node, "regulator-coupled-with", index);
if (!c_node)
return NULL;
c_rdev = of_find_regulator_by_node(c_node);
of_node_put(c_node);
return c_rdev;
}