[PATCH v2 09/13] usb: xhci: simplify Max Scratchpad buffer macros

[Niklas Neronin <niklas.neronin@linux.intel.com>]

Max Scratchpad Buffers consist of two bit-fields:
bits 25:21 - Max Scratchpad Buffers High, 5 Most significant bits
bits 27:31 - Max Scratchpad Buffers Low, 5 Least significant bits
Combined they create the Max Scratchpad Buffers value.

Add two new macros, 'HCS_MAX_SP_HI' and 'HCS_MAX_SP_LO', to separately
extract the high and low parts of the Max Scratchpad Buffers. These are
then combined using 'HCS_MAX_SCRATCHPAD' macro. This change simplifies
the code and makes it similar to other split value register macros in the
xhci driver.

Signed-off-by: Niklas Neronin <niklas.neronin@linux.intel.com>
---
 drivers/usb/host/xhci-caps.h | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/usb/host/xhci-caps.h b/drivers/usb/host/xhci-caps.h
index e772d5f30d36..af47aebc5ba8 100644
--- a/drivers/usb/host/xhci-caps.h
+++ b/drivers/usb/host/xhci-caps.h
@@ -37,9 +37,11 @@
 #define HCS_ERST_MAX(p)		(((p) >> 4) & 0xf)
 /* bits 20:8 - Rsvd */
 /* bits 25:21 - Max Scratchpad Buffers (Hi), 5 Most significant bits */
+#define HCS_MAX_SP_HI(p)	(((p) >> 21) & 0x1f)
 /* bit 26 - Scratchpad restore, for save/restore HW state */
 /* bits 31:27 - Max Scratchpad Buffers (Lo), 5 Least significant bits */
-#define HCS_MAX_SCRATCHPAD(p)   ((((p) >> 16) & 0x3e0) | (((p) >> 27) & 0x1f))
+#define HCS_MAX_SP_LO(p)	(((p) >> 27) & 0x1f)
+#define HCS_MAX_SCRATCHPAD(p)	(HCS_MAX_SP_HI(p) << 5 | HCS_MAX_SP_LO(p))
 
 /* HCSPARAMS3 - hcs_params3 - bitmasks */
 /* bits 7:0 - U1 Device Exit Latency, Max U1 to U0 latency for the roothub ports */
-- 
2.50.1