diff mbox series

[v4,02/12] usb: gadget: composite: Avoid using magic numbers

Message ID dd116fb1325d369c8c6f3c30ae6f785827fa0a22.1595727196.git.thinhn@synopsys.com (mailing list archive)
State Superseded
Headers show
Series usb: Handle different sublink speeds | expand

Commit Message

Thinh Nguyen July 26, 2020, 1:36 a.m. UTC
Magic numbers are difficult to read. Use macros for super-speed-plus BOS
descriptor attributes in the composite driver. They're self-documented.
So there's no need to provide comments as we did previously for the
magic numbers.

Signed-off-by: Thinh Nguyen <thinhn@synopsys.com>
---
 Changes in v4:
 - None
 Changes in v3:
 - None
 Changes in v2:
 - None

 drivers/usb/gadget/composite.c | 41 ++++++++++++++++++++---------------------
 1 file changed, 20 insertions(+), 21 deletions(-)
diff mbox series

Patch

diff --git a/drivers/usb/gadget/composite.c b/drivers/usb/gadget/composite.c
index 05b176c82cc5..0aa4cb49aa53 100644
--- a/drivers/usb/gadget/composite.c
+++ b/drivers/usb/gadget/composite.c
@@ -13,6 +13,7 @@ 
 #include <linux/module.h>
 #include <linux/device.h>
 #include <linux/utsname.h>
+#include <linux/bitfield.h>
 
 #include <linux/usb/composite.h>
 #include <linux/usb/otg.h>
@@ -743,32 +744,30 @@  static int bos_desc(struct usb_composite_dev *cdev)
 		ssp_cap->bReserved = 0;
 		ssp_cap->wReserved = 0;
 
-		/* SSAC = 1 (2 attributes) */
-		ssp_cap->bmAttributes = cpu_to_le32(1);
+		ssp_cap->bmAttributes =
+			cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_ATTRIBS, 1) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_IDS, 0));
 
-		/* Min RX/TX Lane Count = 1 */
 		ssp_cap->wFunctionalitySupport =
-			cpu_to_le16((1 << 8) | (1 << 12));
+			cpu_to_le16(FIELD_PREP(USB_SSP_MIN_SUBLINK_SPEED_ATTRIBUTE_ID, 0) |
+				    FIELD_PREP(USB_SSP_MIN_RX_LANE_COUNT, 1) |
+				    FIELD_PREP(USB_SSP_MIN_TX_LANE_COUNT, 1));
 
-		/*
-		 * bmSublinkSpeedAttr[0]:
-		 *   ST  = Symmetric, RX
-		 *   LSE =  3 (Gbps)
-		 *   LP  =  1 (SuperSpeedPlus)
-		 *   LSM = 10 (10 Gbps)
-		 */
 		ssp_cap->bmSublinkSpeedAttr[0] =
-			cpu_to_le32((3 << 4) | (1 << 14) | (0xa << 16));
-		/*
-		 * bmSublinkSpeedAttr[1] =
-		 *   ST  = Symmetric, TX
-		 *   LSE =  3 (Gbps)
-		 *   LP  =  1 (SuperSpeedPlus)
-		 *   LSM = 10 (10 Gbps)
-		 */
+			cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_SSID, 0) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSE, USB_LSE_GBPS) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_ST,
+					       USB_ST_SYMMETRIC_RX) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LP, USB_LP_SSP) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSM, 10));
+
 		ssp_cap->bmSublinkSpeedAttr[1] =
-			cpu_to_le32((3 << 4) | (1 << 14) |
-				    (0xa << 16) | (1 << 7));
+			cpu_to_le32(FIELD_PREP(USB_SSP_SUBLINK_SPEED_SSID, 0) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSE, USB_LSE_GBPS) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_ST,
+					       USB_ST_SYMMETRIC_TX) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LP, USB_LP_SSP) |
+				    FIELD_PREP(USB_SSP_SUBLINK_SPEED_LSM, 10));
 	}
 
 	return le16_to_cpu(bos->wTotalLength);