[PATCH 6/8] PM / OPP: Separate out _generic_opp_set_rate()

Viresh Kumar
2016-10-04T11:57:33Z

Later patches would add support for custom opp_set_rate callbacks. This
patch separates out the code for generic opp_set_rate handler in order
to prepare for that.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
drivers/base/power/opp/core.c | 181 +++++++++++++++++++++++++++++-------------
drivers/base/power/opp/opp.h | 2 +
include/linux/pm_opp.h | 15 ++++
3 files changed, 145 insertions(+), 53 deletions(-)

diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c
index 45c70ce07864..96f04392daef 100644
--- a/drivers/base/power/opp/core.c
+++ b/drivers/base/power/opp/core.c
@@ -596,6 +596,73 @@ static int _set_opp_voltage(struct device *dev, struct regulator *reg,
return ret;
}

+static inline int
+_generic_opp_set_rate_clk_only(struct device *dev, struct clk *clk,
+ unsigned long old_freq, unsigned long freq)
+{
+ int ret;
+
+ /* Change frequency */
+ dev_dbg(dev, "%s: switching OPP: %lu Hz --> %lu Hz\n",
+ __func__, old_freq, freq);
+
+ ret = clk_set_rate(clk, freq);
+ if (ret) {
+ dev_err(dev, "%s: failed to set clock rate: %d\n", __func__,
+ ret);
+ }
+
+ return ret;
+}
+
+static int _generic_opp_set_rate(struct device *dev,
+ struct dev_pm_set_rate_data *data)
+{
+ struct dev_pm_opp_supply *old_supply = data->old_opp.supplies;
+ struct dev_pm_opp_supply *new_supply = data->new_opp.supplies;
+ unsigned long old_freq = data->old_opp.rate, freq = data->new_opp.rate;
+ struct regulator *reg = data->regulators[0];
+ int ret;
+
+ /* This function only supports single regulator per device */
+ if (WARN_ON(data->regulator_count > 1)) {
+ dev_err(dev, "multiple regulators are not supported\n");
+ return -EINVAL;
+ }
+
+ /* Scaling up? Scale voltage before frequency */
+ if (freq > old_freq) {
+ ret = _set_opp_voltage(dev, reg, new_supply);
+ if (ret)
+ goto restore_voltage;
+ }
+
+ /* Change frequency */
+ ret = _generic_opp_set_rate_clk_only(dev, data->clk, old_freq, freq);
+ if (ret)
+ goto restore_voltage;
+
+ /* Scaling down? Scale voltage after frequency */
+ if (freq < old_freq) {
+ ret = _set_opp_voltage(dev, reg, new_supply);
+ if (ret)
+ goto restore_freq;
+ }
+
+ return 0;
+
+restore_freq:
+ if (_generic_opp_set_rate_clk_only(dev, data->clk, freq, old_freq))
+ dev_err(dev, "%s: failed to restore old-freq (%lu Hz)\n",
+ __func__, old_freq);
+restore_voltage:
+ /* This shouldn't harm even if the voltages weren't updated earlier */
+ if (old_supply->u_volt)
+ _set_opp_voltage(dev, reg, old_supply);
+
+ return ret;
+}
+
/**
* dev_pm_opp_set_rate() - Configure new OPP based on frequency
* @dev: device for which we do this operation
@@ -609,12 +676,12 @@ static int _set_opp_voltage(struct device *dev, struct regulator *reg,
int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
{
struct opp_table *opp_table;
+ unsigned long freq, old_freq;
struct dev_pm_opp *old_opp, *opp;
- struct regulator *reg = ERR_PTR(-ENXIO);
+ struct regulator **regulators;
+ struct dev_pm_set_rate_data *data;
struct clk *clk;
- unsigned long freq, old_freq;
- struct dev_pm_opp_supply old_supply, new_supply;
- int ret;
+ int ret, size;

if (unlikely(!target_freq)) {
dev_err(dev, "%s: Invalid target frequency %lu\n", __func__,
@@ -663,64 +730,32 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)
return ret;
}

- if (opp_table->regulators) {
- /* This function only supports single regulator per device */
- if (WARN_ON(opp_table->regulator_count > 1)) {
- dev_err(dev, "multiple regulators not supported\n");
- rcu_read_unlock();
- return -EINVAL;
- }
+ regulators = opp_table->regulators;

- reg = opp_table->regulators[0];
+ /* Only frequency scaling */
+ if (!regulators) {
+ rcu_read_unlock();
+ return _generic_opp_set_rate_clk_only(dev, clk, old_freq, freq);
}

+ data = opp_table->set_rate_data;
+ data->regulators = regulators;
+ data->regulator_count = opp_table->regulator_count;
+ data->clk = clk;
+
+ data->old_opp.rate = old_freq;
+ size = sizeof(*opp->supplies) * opp_table->regulator_count;
if (IS_ERR(old_opp))
- old_supply.u_volt = 0;
+ memset(data->old_opp.supplies, 0, size);
else
- memcpy(&old_supply, old_opp->supplies, sizeof(old_supply));
+ memcpy(data->old_opp.supplies, old_opp->supplies, size);

- memcpy(&new_supply, opp->supplies, sizeof(new_supply));
+ data->new_opp.rate = freq;
+ memcpy(data->new_opp.supplies, opp->supplies, size);

rcu_read_unlock();

- /* Scaling up? Scale voltage before frequency */
- if (freq > old_freq) {
- ret = _set_opp_voltage(dev, reg, &new_supply);
- if (ret)
- goto restore_voltage;
- }
-
- /* Change frequency */
-
- dev_dbg(dev, "%s: switching OPP: %lu Hz --> %lu Hz\n",
- __func__, old_freq, freq);
-
- ret = clk_set_rate(clk, freq);
- if (ret) {
- dev_err(dev, "%s: failed to set clock rate: %d\n", __func__,
- ret);
- goto restore_voltage;
- }
-
- /* Scaling down? Scale voltage after frequency */
- if (freq < old_freq) {
- ret = _set_opp_voltage(dev, reg, &new_supply);
- if (ret)
- goto restore_freq;
- }
-
- return 0;
-
-restore_freq:
- if (clk_set_rate(clk, old_freq))
- dev_err(dev, "%s: failed to restore old-freq (%lu Hz)\n",
- __func__, old_freq);
-restore_voltage:
- /* This shouldn't harm even if the voltages weren't updated earlier */
- if (old_supply.u_volt)
- _set_opp_voltage(dev, reg, &old_supply);
-
- return ret;
+ return _generic_opp_set_rate(dev, data);
}
EXPORT_SYMBOL_GPL(dev_pm_opp_set_rate);

@@ -1353,6 +1388,38 @@ void dev_pm_opp_put_prop_name(struct device *dev)
}
EXPORT_SYMBOL_GPL(dev_pm_opp_put_prop_name);

+static int _allocate_set_rate_data(struct opp_table *opp_table)
+{
+ struct dev_pm_set_rate_data *data;
+ int len, count = opp_table->regulator_count;
+
+ if (WARN_ON(!count))
+ return -EINVAL;
+
+ /* space for set_rate_data */
+ len = sizeof(*data);
+
+ /* space for old_opp.supplies and new_opp.supplies */
+ len += 2 * sizeof(struct dev_pm_opp_supply) * count;
+
+ data = kzalloc(len, GFP_KERNEL);
+ if (!data)
+ return -ENOMEM;
+
+ data->old_opp.supplies = (void *)(data + 1);
+ data->new_opp.supplies = data->old_opp.supplies + count;
+
+ opp_table->set_rate_data = data;
+
+ return 0;
+}
+
+static void _free_set_rate_data(struct opp_table *opp_table)
+{
+ kfree(opp_table->set_rate_data);
+ opp_table->set_rate_data = NULL;
+}
+
/**
* dev_pm_opp_set_regulators() - Set regulator names for the device
* @dev: Device for which regulator name is being set.
@@ -1420,6 +1487,11 @@ int dev_pm_opp_set_regulators(struct device *dev, const char *names[],

opp_table->regulator_count = count;

+ /* Allocate block only once to pass to ->set_rate() */
+ ret = _allocate_set_rate_data(opp_table);
+ if (ret)
+ goto free_regulators;
+
mutex_unlock(&opp_table_lock);
return 0;

@@ -1429,6 +1501,7 @@ int dev_pm_opp_set_regulators(struct device *dev, const char *names[],

kfree(opp_table->regulators);
opp_table->regulators = NULL;
+ opp_table->regulator_count = 0;
err:
_remove_opp_table(opp_table);
unlock:
@@ -1474,6 +1547,8 @@ void dev_pm_opp_put_regulators(struct device *dev)
for (i = opp_table->regulator_count - 1; i >= 0; i--)
regulator_put(opp_table->regulators[i]);

+ _free_set_rate_data(opp_table);
+
kfree(opp_table->regulators);
opp_table->regulators = NULL;
opp_table->regulator_count = 0;
diff --git a/drivers/base/power/opp/opp.h b/drivers/base/power/opp/opp.h
index d3f0861f9bff..28011d6da345 100644
--- a/drivers/base/power/opp/opp.h
+++ b/drivers/base/power/opp/opp.h
@@ -194,6 +194,8 @@ struct opp_table {
struct regulator **regulators;
unsigned int regulator_count;

+ struct dev_pm_set_rate_data *set_rate_data;
+
#ifdef CONFIG_DEBUG_FS
struct dentry *dentry;
char dentry_name[NAME_MAX];
diff --git a/include/linux/pm_opp.h b/include/linux/pm_opp.h
index 0606b70a8b97..630f0fd6065c 100644
--- a/include/linux/pm_opp.h
+++ b/include/linux/pm_opp.h
@@ -17,6 +17,7 @@
#include <linux/err.h>
#include <linux/notifier.h>

+struct clk;
struct dev_pm_opp;
struct device;

@@ -24,6 +25,20 @@ enum dev_pm_opp_event {
OPP_EVENT_ADD, OPP_EVENT_REMOVE, OPP_EVENT_ENABLE, OPP_EVENT_DISABLE,
};

+struct dev_pm_opp_info {
+ unsigned long rate;
+ struct dev_pm_opp_supply *supplies;
+};
+
+struct dev_pm_set_rate_data {
+ struct dev_pm_opp_info old_opp;
+ struct dev_pm_opp_info new_opp;
+
+ struct regulator **regulators;
+ unsigned int regulator_count;
+ struct clk *clk;
+};
+
#if defined(CONFIG_PM_OPP)

unsigned long dev_pm_opp_get_voltage(struct dev_pm_opp *opp);
--
2.7.1.410.g6faf27b