[RFC PATCH v1 2/6] regulator: core: Parse max-spread value per regulator couple

Dmitry Osipenko
2019-04-14T18:06:02Z

Parse and validate max-spread value per regulator couple. Now regulator
core can take multiple regulator couples, although balancing is still
limited to a single couple.

Signed-off-by: Dmitry Osipenko <digetx@gmail.com>
---
drivers/regulator/core.c | 13 ++++----
drivers/regulator/of_regulator.c | 49 +++++++++++++++++++++----------
include/linux/regulator/machine.h | 3 +-
3 files changed, 43 insertions(+), 22 deletions(-)

diff --git a/drivers/regulator/core.c b/drivers/regulator/core.c
index a98af47e0feb..cdb25bbee631 100644
--- a/drivers/regulator/core.c
+++ b/drivers/regulator/core.c
@@ -3440,7 +3440,7 @@ static int regulator_get_optimal_voltage(struct regulator_dev *rdev,
struct coupling_desc *c_desc = &rdev->coupling_desc;
struct regulator_dev **c_rdevs = c_desc->coupled_rdevs;
struct regulation_constraints *constraints = rdev->constraints;
- int max_spread = constraints->max_spread;
+ int max_spread = constraints->max_spread[0];
int desired_min_uV = 0, desired_max_uV = INT_MAX;
int max_current_uV = 0, min_current_uV = INT_MAX;
int highest_min_uV = 0, target_uV, possible_uV;
@@ -3604,6 +3604,12 @@ static int regulator_balance_voltage(struct regulator_dev *rdev,
return machine_regulators_coupler->balance_voltage(
machine_regulators_coupler, rdev, state);

+ if (n_coupled > 2) {
+ rdev_err(rdev,
+ "Voltage balancing for multiple regulator couples is unimplemented\n");
+ return -EPERM;
+ }
+
for (i = 0; i < n_coupled; i++)
c_rdev_done[i] = false;

@@ -4821,11 +4827,6 @@ static int regulator_init_coupling(struct regulator_dev *rdev)
return -EPERM;
}

- if (rdev->constraints->max_spread <= 0) {
- rdev_err(rdev, "wrong max_spread value\n");
- return -EPERM;
- }
-
if (!of_check_coupling_data(rdev))
return -EPERM;

diff --git a/drivers/regulator/of_regulator.c b/drivers/regulator/of_regulator.c
index 6dca0ba044d8..ccca09de92d6 100644
--- a/drivers/regulator/of_regulator.c
+++ b/drivers/regulator/of_regulator.c
@@ -34,8 +34,14 @@ static void of_get_regulation_constraints(struct device_node *np,
struct device_node *suspend_np;
unsigned int mode;
int ret, i, len;
+ int n_phandles;
+ u32 pvals[MAX_COUPLED];
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))
@@ -167,9 +173,12 @@ static void of_get_regulation_constraints(struct device_node *np,
if (!of_property_read_u32(np, "regulator-system-load", &pval))
constraints->system_load = pval;

- if (!of_property_read_u32(np, "regulator-coupled-max-spread",
- &pval))
- constraints->max_spread = pval;
+ if (!of_property_read_u32_array(np, "regulator-coupled-max-spread",
+ pvals, n_phandles)) {
+
+ for (i = 0; i < n_phandles; i++)
+ constraints->max_spread[i] = pvals[i];
+ }

if (!of_property_read_u32(np, "regulator-max-step-microvolt",
&pval))
@@ -477,7 +486,8 @@ int of_get_n_coupled(struct regulator_dev *rdev)

/* 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)
+ struct device_node *to_find,
+ int *index)
{
int n_phandles, i;
bool found = false;
@@ -499,8 +509,10 @@ static bool of_coupling_find_node(struct device_node *src,

of_node_put(tmp);

- if (found)
+ if (found) {
+ *index = i;
break;
+ }
}

return found;
@@ -521,22 +533,28 @@ static bool of_coupling_find_node(struct device_node *src,
*/
bool of_check_coupling_data(struct regulator_dev *rdev)
{
- int max_spread = rdev->constraints->max_spread;
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;

- if (max_spread <= 0) {
- dev_err(&rdev->dev, "max_spread value invalid\n");
+ if (n_phandles >= MAX_COUPLED) {
+ dev_err(&rdev->dev, "please bump MAX_COUPLED number\n");
return false;
}

/* 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);

@@ -553,22 +571,23 @@ bool of_check_coupling_data(struct regulator_dev *rdev)
goto clean;
}

- if (of_property_read_u32(c_node, "regulator-coupled-max-spread",
- &c_max_spread)) {
+ 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 (c_max_spread != max_spread) {
- dev_err(&rdev->dev,
- "coupled regulators max_spread mismatch\n");
+ if (of_property_read_u32_index(c_node, "regulator-coupled-max-spread",
+ index, &c_max_spread)) {
ret = false;
goto clean;
}

- if (!of_coupling_find_node(c_node, node)) {
- dev_err(&rdev->dev, "missing 2-way linking for coupled regulators\n");
+ if (c_max_spread != max_spread) {
+ dev_err(&rdev->dev,
+ "coupled regulators max_spread mismatch\n");
ret = false;
+ goto clean;
}

clean:
diff --git a/include/linux/regulator/machine.h b/include/linux/regulator/machine.h
index f15c8c5f7f6c..0ade1247d3f6 100644
--- a/include/linux/regulator/machine.h
+++ b/include/linux/regulator/machine.h
@@ -15,6 +15,7 @@
#ifndef __LINUX_REGULATOR_MACHINE_H_
#define __LINUX_REGULATOR_MACHINE_H_

+#include <linux/regulator/driver.h>
#include <linux/regulator/consumer.h>
#include <linux/suspend.h>

@@ -157,7 +158,7 @@ struct regulation_constraints {
int system_load;

/* used for coupled regulators */
- int max_spread;
+ int max_spread[MAX_COUPLED];

/* used for changing voltage in steps */
int max_uV_step;
--
2.21.0