On 12/22, Viresh Kumar wrote:
diff --git a/drivers/base/power/opp/core.c b/drivers/base/power/opp/core.c index 1d1b0faa825d..c76818f69f14 100644 --- a/drivers/base/power/opp/core.c +++ b/drivers/base/power/opp/core.c @@ -517,6 +517,148 @@ struct dev_pm_opp *dev_pm_opp_find_freq_floor(struct device *dev, } EXPORT_SYMBOL_GPL(dev_pm_opp_find_freq_floor); +/*
- _set_opp_voltage() - Configure device supply for an OPP
- @dev: device for which we do this operation
- @dev_opp: dev_opp for the device
- @opp: opp for getting supply voltage levels
- This is used to configure the power supply, used by the device, to the
- voltage levels specified by a particular OPP.
- */
+static int _set_opp_voltage(struct device *dev, struct device_opp *dev_opp,
struct dev_pm_opp *opp)
+{
- struct regulator *reg = dev_opp->regulator;
- int ret;
- /* Regulator not be available for device */
- if (IS_ERR(reg)) {
dev_dbg(dev, "%s: regulator not available: %ld\n", __func__,
PTR_ERR(reg));
return 0;
- }
- dev_dbg(dev, "%s: voltages (mV): %lu %lu %lu\n", __func__,
opp->u_volt_min, opp->u_volt, opp->u_volt_max);
- ret = regulator_set_voltage_triplet(reg, opp->u_volt_min, opp->u_volt,
This can't be called under an RCU read lock.
opp->u_volt_max);
- if (ret)
dev_err(dev, "%s: failed to set voltage (%lu %lu %lu mV): %d\n",
__func__, opp->u_volt_min, opp->u_volt, opp->u_volt_max,
ret);
- return ret;
+}
+/**
- dev_pm_opp_set_rate() - Configure new OPP based on frequency
- @dev: device for which we do this operation
- @target_freq: frequency to achieve
- This configures the power-supplies and clock source to the levels specified
- by the OPP corresponding to the target_freq. It takes all necessary locks
- required for the operation and the caller doesn't need to care about the rcu
- locks.
- */
+int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq) +{
- struct device_opp *dev_opp;
- struct dev_pm_opp *old_opp, *opp;
- struct clk *clk;
- unsigned long freq, old_freq;
- int ret;
- if (unlikely(!target_freq)) {
dev_err(dev, "%s: Invalid target frequemncy %lu\n", __func__,
s/frequemncy/frequency/
target_freq);
return -EINVAL;
- }
- rcu_read_lock();
This lock is held way too long.
- dev_opp = _find_device_opp(dev);
- if (IS_ERR(dev_opp)) {
dev_err(dev, "%s: device opp doesn't exist\n", __func__);
ret = PTR_ERR(dev_opp);
goto unlock;
- }
- clk = dev_opp->clk;
- if (IS_ERR(clk)) {
dev_err(dev, "%s: No clock available for the device\n",
__func__);
ret = -EINVAL;
goto unlock;
- }
- freq = clk_round_rate(clk, target_freq);
This can't be called under RCU.
- if ((long)freq <= 0)
freq = target_freq;
- old_freq = clk_get_rate(clk);
Same for this.
- /* Return early if nothing to do */
- if (old_freq == freq) {
dev_dbg(dev, "%s: old/new frequencies (%lu Hz) are same, nothing to do\n",
__func__, freq);
ret = 0;
goto unlock;
- }
- old_opp = dev_pm_opp_find_freq_ceil(dev, &old_freq);
- opp = dev_pm_opp_find_freq_ceil(dev, &freq);
- if (IS_ERR(opp)) {
ret = PTR_ERR(opp);
dev_err(dev, "%s: failed to find OPP for freq %lu (%d)\n",
__func__, freq, ret);
goto unlock;
- }
- /* Scaling up? Scale voltage before frequency */
- if (freq > old_freq) {
ret = _set_opp_voltage(dev, dev_opp, opp);
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);
And same for this.