[PATCH] igc: change default return of igc_read_phy_reg()

From: Tom Rix <trix@redhat.com>

Static analysis reports this problem

igc_main.c:4944:20: warning: The left operand of '&'
  is a garbage value
    if (!(phy_data & SR_1000T_REMOTE_RX_STATUS) &&
          ~~~~~~~~ ^

pyy_data is set by the call to igc_read_phy_reg() only if
there is a read_reg() op, else it is unset and a 0 is
returned.  Change the return to -EOPNOTSUPP.

Fixes: 208983f099d9 ("igc: Add watchdog")
Signed-off-by: Tom Rix <trix@redhat.com>
---
 drivers/net/ethernet/intel/igc/igc.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/ethernet/intel/igc/igc.h b/drivers/net/ethernet/intel/igc/igc.h
index b6d3277c6f520..71100ee7afbee 100644
--- a/drivers/net/ethernet/intel/igc/igc.h
+++ b/drivers/net/ethernet/intel/igc/igc.h

@@ -577,7 +577,7 @@ static inline s32 igc_read_phy_reg(struct igc_hw *hw, u32 offset, u16 *data)
 	if (hw->phy.ops.read_reg)
 		return hw->phy.ops.read_reg(hw, offset, data);
 
-	return 0;
+	return -EOPNOTSUPP;
 }
 
 void igc_reinit_locked(struct igc_adapter *);

-- 
2.26.3

On 5/21/2021 22:50, trix@redhat.com wrote:

From: Tom Rix <trix@redhat.com>

Static analysis reports this problem

igc_main.c:4944:20: warning: The left operand of '&'
   is a garbage value
     if (!(phy_data & SR_1000T_REMOTE_RX_STATUS) &&
           ~~~~~~~~ ^

Tom, thanks for this patch. I believe the same static analysis problem 
should be with the 'igb_read_phy_reg' method:
https://elixir.bootlin.com/linux/v5.13-rc1/source/drivers/net/ethernet/intel/igb/igb.h#L769

pyy_data is set by the call to igc_read_phy_reg() only if

%s/pyy_data/phy_data/gc (typo)

Thanks,
Sasha

On 5/21/2021 22:50, trix@redhat.com wrote:

From: Tom Rix <trix@redhat.com>

Static analysis reports this problem

igc_main.c:4944:20: warning: The left operand of '&'
   is a garbage value
     if (!(phy_data & SR_1000T_REMOTE_RX_STATUS) &&
           ~~~~~~~~ ^

pyy_data is set by the call to igc_read_phy_reg() only if
there is a read_reg() op, else it is unset and a 0 is
returned.  Change the return to -EOPNOTSUPP.

Fixes: 208983f099d9 ("igc: Add watchdog")
Signed-off-by: Tom Rix <trix@redhat.com>
---
  drivers/net/ethernet/intel/igc/igc.h | 2 +-
  1 file changed, 1 insertion(+), 1 deletion(-)

Tested-by: Dvora Fuxbrumer <redacted>