Re: [RFC v2 02/11] OPP: Make dev_pm_opp_set_rate() with freq=0 as valid

Viresh Kumar
2019-06-14T06:32:16Z

On 20-03-19, 15:19, Rajendra Nayak wrote:
> For devices with performance state, we use dev_pm_opp_set_rate()
> to set the appropriate clk rate and the performance state.
> We do need a way to *remove* the performance state vote when
> we idle the device and turn the clocks off. Use dev_pm_opp_set_rate()
> with freq=0 to achieve this.
>
> Signed-off-by: Rajendra Nayak <rnayak@codeaurora.org>
> Signed-off-by: Stephen Boyd <swboyd@chromium.org>
> ---
> drivers/opp/core.c | 18 ++++++++++++------
> 1 file changed, 12 insertions(+), 6 deletions(-)

What about this instead ?

diff --git a/drivers/opp/core.c b/drivers/opp/core.c
index 2fe96c2363a3..9accf8bb6afc 100644
--- a/drivers/opp/core.c
+++ b/drivers/opp/core.c
@@ -711,7 +711,7 @@ static int _set_required_opps(struct device *dev,

/* Single genpd case */
if (!genpd_virt_devs) {
- pstate = opp->required_opps[0]->pstate;
+ pstate = likely(opp) ? opp->required_opps[0]->pstate : 0;
ret = dev_pm_genpd_set_performance_state(dev, pstate);
if (ret) {
dev_err(dev, "Failed to set performance state of %s: %d (%d)\n",
@@ -729,7 +729,7 @@ static int _set_required_opps(struct device *dev,
mutex_lock(&opp_table->genpd_virt_dev_lock);

for (i = 0; i < opp_table->required_opp_count; i++) {
- pstate = opp->required_opps[i]->pstate;
+ pstate = likely(opp) ? opp->required_opps[i]->pstate : 0;

if (!genpd_virt_devs[i])
continue;
@@ -770,14 +770,13 @@ int dev_pm_opp_set_rate(struct device *dev, unsigned long target_freq)

if (unlikely(!target_freq)) {
if (opp_table->required_opp_tables) {
- /* drop the performance state vote */
- dev_pm_genpd_set_performance_state(dev, 0);
- return 0;
+ ret = _set_required_opps(dev, opp_table, NULL);
} else {
- dev_err(dev, "%s: Invalid target frequency %lu\n", __func__,
- target_freq);
- return -EINVAL;
+ dev_err(dev, "target frequency can't be 0\n");
+ ret = -EINVAL;
}
+
+ goto put_opp_table;
}

clk = opp_table->clk;