Re: [PATCH] phy: core: Allow phy_pm_runtime_xxx API calls with NULL phy

[Vivek Gautam]

On 2018-03-16 14:40, Manu Gautam wrote:

phy_init() and phy_exit() calls, and phy_power_on() and
phy_power_off() already accept NULL as valid PHY refernece
and act as NOP. Extend same concept to phy runtime_pm APIs
to keep drivers (e.g. dwc3) code simple while dealing with
optional PHYs.

Signed-off-by: Manu Gautam 
---
 drivers/phy/phy-core.c | 18 ++
 1 file changed, 18 insertions(+)

diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
index 09ac8af..48b9615 100644
--- a/drivers/phy/phy-core.c
+++ b/drivers/phy/phy-core.c
@@ -153,6 +153,9 @@ int phy_pm_runtime_get(struct phy *phy)
 {
int ret;

+   if (!phy)
+   return 0;
+
if (!pm_runtime_enabled(&phy->dev))


Were we already trying to dereference a NULL here?
That shouldn't be good i guess.
Kishon, do we not expect phys to be NULL here?



regards
Vivek

Re: [PATCH] phy: core: Allow phy_pm_runtime_xxx API calls with NULL phy

[kbuild test robot]

Hi Manu,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on v4.16-rc4]
[also build test WARNING on next-20180316]
[if your patch is applied to the wrong git tree, please drop us a note to help 
improve the system]

url:
https://github.com/0day-ci/linux/commits/Manu-Gautam/phy-core-Allow-phy_pm_runtime_xxx-API-calls-with-NULL-phy/20180317-114302
config: x86_64-randconfig-x002-201810 (attached as .config)
compiler: gcc-7 (Debian 7.3.0-1) 7.3.0
reproduce:
# save the attached .config to linux build tree
make ARCH=x86_64 

All warnings (new ones prefixed by >>):

   drivers/phy/phy-core.c: In function 'phy_pm_runtime_allow':
>> drivers/phy/phy-core.c:215:10: warning: 'return' with a value, in function 
>> returning void
  return 0;
 ^
   drivers/phy/phy-core.c:212:6: note: declared here
void phy_pm_runtime_allow(struct phy *phy)
 ^~~~
   drivers/phy/phy-core.c: In function 'phy_pm_runtime_forbid':
   drivers/phy/phy-core.c:227:10: warning: 'return' with a value, in function 
returning void
  return 0;
 ^
   drivers/phy/phy-core.c:224:6: note: declared here
void phy_pm_runtime_forbid(struct phy *phy)
 ^

vim +/return +215 drivers/phy/phy-core.c

   211  
   212  void phy_pm_runtime_allow(struct phy *phy)
   213  {
   214  if (!phy)
 > 215  return 0;
   216  
   217  if (!pm_runtime_enabled(&phy->dev))
   218  return;
   219  
   220  pm_runtime_allow(&phy->dev);
   221  }
   222  EXPORT_SYMBOL_GPL(phy_pm_runtime_allow);
   223  

---
0-DAY kernel test infrastructureOpen Source Technology Center
https://lists.01.org/pipermail/kbuild-all   Intel Corporation


.config.gz
Description: application/gzip

[PATCH] phy: core: Allow phy_pm_runtime_xxx API calls with NULL phy

[Manu Gautam]

phy_init() and phy_exit() calls, and phy_power_on() and
phy_power_off() already accept NULL as valid PHY refernece
and act as NOP. Extend same concept to phy runtime_pm APIs
to keep drivers (e.g. dwc3) code simple while dealing with
optional PHYs.

Signed-off-by: Manu Gautam 
---
 drivers/phy/phy-core.c | 18 ++
 1 file changed, 18 insertions(+)

diff --git a/drivers/phy/phy-core.c b/drivers/phy/phy-core.c
index 09ac8af..48b9615 100644
--- a/drivers/phy/phy-core.c
+++ b/drivers/phy/phy-core.c
@@ -153,6 +153,9 @@ int phy_pm_runtime_get(struct phy *phy)
 {
int ret;
 
+   if (!phy)
+   return 0;
+
if (!pm_runtime_enabled(&phy->dev))
return -ENOTSUPP;
 
@@ -168,6 +171,9 @@ int phy_pm_runtime_get_sync(struct phy *phy)
 {
int ret;
 
+   if (!phy)
+   return 0;
+
if (!pm_runtime_enabled(&phy->dev))
return -ENOTSUPP;
 
@@ -181,6 +187,9 @@ int phy_pm_runtime_get_sync(struct phy *phy)
 
 int phy_pm_runtime_put(struct phy *phy)
 {
+   if (!phy)
+   return 0;
+
if (!pm_runtime_enabled(&phy->dev))
return -ENOTSUPP;
 
@@ -190,6 +199,9 @@ int phy_pm_runtime_put(struct phy *phy)
 
 int phy_pm_runtime_put_sync(struct phy *phy)
 {
+   if (!phy)
+   return 0;
+
if (!pm_runtime_enabled(&phy->dev))
return -ENOTSUPP;
 
@@ -199,6 +211,9 @@ int phy_pm_runtime_put_sync(struct phy *phy)
 
 void phy_pm_runtime_allow(struct phy *phy)
 {
+   if (!phy)
+   return 0;
+
if (!pm_runtime_enabled(&phy->dev))
return;
 
@@ -208,6 +223,9 @@ void phy_pm_runtime_allow(struct phy *phy)
 
 void phy_pm_runtime_forbid(struct phy *phy)
 {
+   if (!phy)
+   return 0;
+
if (!pm_runtime_enabled(&phy->dev))
return;
 
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