2021-03-25 06:46:05

by quanyang wang

Subject: [V2][PATCH] cpufreq: dt: check the -EPROBE_DEFER error returned by dev_pm_opp_of_cpumask_add_table

From: Quanyang Wang <[email protected]>

The function dev_pm_opp_of_cpumask_add_table may return -EPROBE_DEFER
which comes from clk_get(dev, NULL) in _update_opp_table_clk. Ignoring
this error and call the next function dev_pm_opp_of_cpumask_add_table
may cause dt_cpufreq_probe return -ENODEV instead of -EPROBE_DEFER.
And this will result cpufreq-dt driver probe failure.

Add check condition to fix this issue.

Signed-off-by: Quanyang Wang <[email protected]>
---
drivers/cpufreq/cpufreq-dt.c | 7 ++++++-
1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c
index b1e1bdc63b01..25e46df92941 100644
--- a/drivers/cpufreq/cpufreq-dt.c
+++ b/drivers/cpufreq/cpufreq-dt.c
@@ -257,7 +257,12 @@ static int dt_cpufreq_early_init(struct device *dev, int cpu)
*
* OPPs might be populated at runtime, don't check for error here.
*/
- if (!dev_pm_opp_of_cpumask_add_table(priv->cpus))
+ ret = dev_pm_opp_of_cpumask_add_table(priv->cpus);
+ if (ret) {
+ /* Return the -EPROBE_DEFER error to trigger the deferred probe. */
+ if (ret == -EPROBE_DEFER)
+ goto out;
+ } else
priv->have_static_opps = true;

/*
--
2.25.1

2021-03-25 07:16:27

by Viresh Kumar

Subject: Re: [V2][PATCH] cpufreq: dt: check the -EPROBE_DEFER error returned by dev_pm_opp_of_cpumask_add_table

On 25-03-21, 14:42, [email protected] wrote:
> From: Quanyang Wang <[email protected]>

Made some changes and applied this:

Author: Quanyang Wang <[email protected]>
Date: Thu Mar 25 14:42:08 2021 +0800

cpufreq: dt: dev_pm_opp_of_cpumask_add_table() may return -EPROBE_DEFER

The function dev_pm_opp_of_cpumask_add_table() may return -EPROBE_DEFER,
which needs to be propagated to the caller to try probing the driver
later on.

Signed-off-by: Quanyang Wang <[email protected]>
[ Viresh: Massage changelog/subject, improve code. ]
Signed-off-by: Viresh Kumar <[email protected]>
---
drivers/cpufreq/cpufreq-dt.c | 9 +++++++--
1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/drivers/cpufreq/cpufreq-dt.c b/drivers/cpufreq/cpufreq-dt.c
index b1e1bdc63b01..ece52863ba62 100644
--- a/drivers/cpufreq/cpufreq-dt.c
+++ b/drivers/cpufreq/cpufreq-dt.c
@@ -255,10 +255,15 @@ static int dt_cpufreq_early_init(struct device *dev, int cpu)
* before updating priv->cpus. Otherwise, we will end up creating
* duplicate OPPs for the CPUs.
*
- * OPPs might be populated at runtime, don't check for error here.
+ * OPPs might be populated at runtime, don't fail for error here unless
+ * it is -EPROBE_DEFER.
*/
- if (!dev_pm_opp_of_cpumask_add_table(priv->cpus))
+ ret = dev_pm_opp_of_cpumask_add_table(priv->cpus);
+ if (!ret) {
priv->have_static_opps = true;
+ } else if (ret == -EPROBE_DEFER) {
+ goto out;
+ }

/*
* The OPP table must be initialized, statically or dynamically, by this

--
viresh