i40e: field get conversion

Refactor the i40e driver to use FIELD_GET() for mask and shift reads,
which reduces lines of code and adds clarity of intent.

This code was generated by the following coccinelle/spatch script and
then manually repaired.

While making one of the conversions, an if() check was inverted to
return early and avoid un-necessary indentation of the remainder of the
function. In some other cases a stack variable was moved inside the
block where it was used while doing cleanups/review.

A couple places were changed to use le16_get_bits() instead of FIELD_GET
with a le16_to_cpu combination.

@get@
constant shift,mask;
metavariable type T;
expression a;
@@
-(((T)(a) & mask) >> shift)
+FIELD_GET(mask, a)

and applied via:
spatch --sp-file field_prep.cocci --in-place --dir \
 drivers/net/ethernet/intel/

Cc: Julia Lawall <Julia.Lawall@inria.fr>
Reviewed-by: Aleksandr Loktionov <aleksandr.loktionov@intel.com>
Reviewed-by: Marcin Szycik <marcin.szycik@linux.intel.com>
Reviewed-by: Simon Horman <horms@kernel.org>
Signed-off-by: Jesse Brandeburg <jesse.brandeburg@intel.com>
Tested-by: Pucha Himasekhar Reddy <himasekharx.reddy.pucha@intel.com> (A Contingent worker at Intel)
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>

1 files changed, 1 insertions, 2 deletions

diff --git a/drivers/net/ethernet/intel/i40e/i40e_dcb_nl.c b/drivers/net/ethernet/intel/i40e/i40e_dcb_nl.c
index 4721845fda6e..b96a92187ab3 100644
--- a/drivers/net/ethernet/intel/i40e/i40e_dcb_nl.c
+++ b/drivers/net/ethernet/intel/i40e/i40e_dcb_nl.c
@@ -21,8 +21,7 @@ static void i40e_get_pfc_delay(struct i40e_hw *hw, u16 *delay)
 	u32 val;
 
 	val = rd32(hw, I40E_PRTDCB_GENC);
-	*delay = (u16)((val & I40E_PRTDCB_GENC_PFCLDA_MASK) >>
-		       I40E_PRTDCB_GENC_PFCLDA_SHIFT);
+	*delay = FIELD_GET(I40E_PRTDCB_GENC_PFCLDA_MASK, val);
 }
 
 /**