Handle the NULL pointer case

Fixes New smatch warnings:
drivers/net/phy/micrel.c:2613 lan8814_ptp_probe_once() warn: passing zero to 'PTR_ERR'

vim +/PTR_ERR +2613 drivers/net/phy/micrel.c
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Fixes: ece19502834d ("net: phy: micrel: 1588 support for LAN8814 phy")
Signed-off-by: Divya Koppera <Divya.Koppera@microchip.com>
---
v4 -> v5:
- Removed run time check and added compile time check for PHC

v3 -> v4:
- Split the patch for different warnings
- Renamed variable from shared_priv to shared.

v2 -> v3:
- Changed subject line from net to net-next
- Removed config check for ptp and clock configuration
  instead added null check for ptp_clock
- Fixed one more warning related to initialisaton.

v1 -> v2:
- Handled NULL pointer case
- Changed subject line with net-next to net
---
 drivers/net/phy/micrel.c | 10 +++++-----
 1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
index 1bcdb828db56..650ef53fcf20 100644
--- a/drivers/net/phy/micrel.c
+++ b/drivers/net/phy/micrel.c
@@ -3017,10 +3017,6 @@ static int lan8814_ptp_probe_once(struct phy_device *phydev)
 {
 	struct lan8814_shared_priv *shared = phydev->shared->priv;

-	if (!IS_ENABLED(CONFIG_PTP_1588_CLOCK) ||
-	    !IS_ENABLED(CONFIG_NETWORK_PHY_TIMESTAMPING))
-		return 0;
-
 	/* Initialise shared lock for clock*/
 	mutex_init(&shared->shared_lock);

@@ -3040,12 +3036,16 @@ static int lan8814_ptp_probe_once(struct phy_device *phydev)

 	shared->ptp_clock = ptp_clock_register(&shared->ptp_clock_info,
 					       &phydev->mdio.dev);
-	if (IS_ERR_OR_NULL(shared->ptp_clock)) {
+	if (IS_ERR(shared->ptp_clock)) {
 		phydev_err(phydev, "ptp_clock_register failed %lu\n",
 			   PTR_ERR(shared->ptp_clock));
 		return -EINVAL;
 	}

+	/* Check if PHC support is missing at the configuration level */
+	if (!shared->ptp_clock)
+		return 0;
+
 	phydev_dbg(phydev, "successfully registered ptp clock\n");

 	shared->phydev = phydev;
--
2.17.1

On Wed, 2022-12-14 at 14:55 +0530, Divya Koppera wrote:
> Handle the NULL pointer case
> 
> Fixes New smatch warnings:
> drivers/net/phy/micrel.c:2613 lan8814_ptp_probe_once() warn: passing zero to 'PTR_ERR'
> 
> vim +/PTR_ERR +2613 drivers/net/phy/micrel.c
> Reported-by: kernel test robot <lkp@intel.com>
> Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
> Fixes: ece19502834d ("net: phy: micrel: 1588 support for LAN8814 phy")
> Signed-off-by: Divya Koppera <Divya.Koppera@microchip.com>
> ---
> v4 -> v5:
> - Removed run time check and added compile time check for PHC
> 
> v3 -> v4:
> - Split the patch for different warnings
> - Renamed variable from shared_priv to shared.
> 
> v2 -> v3:
> - Changed subject line from net to net-next
> - Removed config check for ptp and clock configuration
>   instead added null check for ptp_clock
> - Fixed one more warning related to initialisaton.
> 
> v1 -> v2:
> - Handled NULL pointer case
> - Changed subject line with net-next to net
> ---
>  drivers/net/phy/micrel.c | 10 +++++-----
>  1 file changed, 5 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/net/phy/micrel.c b/drivers/net/phy/micrel.c
> index 1bcdb828db56..650ef53fcf20 100644
> --- a/drivers/net/phy/micrel.c
> +++ b/drivers/net/phy/micrel.c
> @@ -3017,10 +3017,6 @@ static int lan8814_ptp_probe_once(struct phy_device *phydev)
>  {
>  	struct lan8814_shared_priv *shared = phydev->shared->priv;
> 
> -	if (!IS_ENABLED(CONFIG_PTP_1588_CLOCK) ||
> -	    !IS_ENABLED(CONFIG_NETWORK_PHY_TIMESTAMPING))
> -		return 0;
> -
>  	/* Initialise shared lock for clock*/
>  	mutex_init(&shared->shared_lock);
> 
> @@ -3040,12 +3036,16 @@ static int lan8814_ptp_probe_once(struct phy_device *phydev)
> 
>  	shared->ptp_clock = ptp_clock_register(&shared->ptp_clock_info,
>  					       &phydev->mdio.dev);
> -	if (IS_ERR_OR_NULL(shared->ptp_clock)) {
> +	if (IS_ERR(shared->ptp_clock)) {
>  		phydev_err(phydev, "ptp_clock_register failed %lu\n",
>  			   PTR_ERR(shared->ptp_clock));
>  		return -EINVAL;
>  	}
> 
> +	/* Check if PHC support is missing at the configuration level */
> +	if (!shared->ptp_clock)
> +		return 0;
> +
>  	phydev_dbg(phydev, "successfully registered ptp clock\n");
> 
>  	shared->phydev = phydev;
> 

Looks good to me. You may need to resubmit once net-next opens.

Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>

On Thu, 15 Dec 2022 07:58:57 -0800 Alexander H Duyck wrote:
> Looks good to me. You may need to resubmit once net-next opens.

And please drop the Fixes tags when reposting. Both patches look
like placating static analysis tools but there's not real issue.