staging: gdm724x: update HCI structs with new bitwise types

Update the driver's HCI structs and associated endian-converter
functions with new driver-specific bitwise types. The new types
encourage correct endian-handling within the driver by triggering
sparse warnings when mixing with other types. The driver's
endian-converters provide correct and warning-free conversions.

Driver-specific bitwise types are used instead of the standard
endian-specific types because the attached device can be of either
endian. This is also why the driver has its own endian-conversion
functions, which consider endianness of both the cpu and the attached
device.

Introducing the new types to the converters fixes the sparse warnings:

CHECK   drivers/staging/gdm724x/gdm_endian.c
drivers/staging/gdm724x/gdm_endian.c:28:24: warning: incorrect type in return expression (different base types)
drivers/staging/gdm724x/gdm_endian.c:28:24:    expected unsigned short
drivers/staging/gdm724x/gdm_endian.c:28:24:    got restricted __le16 [usertype] <noident>
drivers/staging/gdm724x/gdm_endian.c:30:24: warning: incorrect type in return expression (different base types)
drivers/staging/gdm724x/gdm_endian.c:30:24:    expected unsigned short
drivers/staging/gdm724x/gdm_endian.c:30:24:    got restricted __be16 [usertype] <noident>
drivers/staging/gdm724x/gdm_endian.c:36:24: warning: cast to restricted __le16
drivers/staging/gdm724x/gdm_endian.c:38:24: warning: cast to restricted __be16
drivers/staging/gdm724x/gdm_endian.c:44:24: warning: incorrect type in return expression (different base types)
drivers/staging/gdm724x/gdm_endian.c:44:24:    expected unsigned int
drivers/staging/gdm724x/gdm_endian.c:44:24:    got restricted __le32 [usertype] <noident>
drivers/staging/gdm724x/gdm_endian.c:46:24: warning: incorrect type in return expression (different base types)
drivers/staging/gdm724x/gdm_endian.c:46:24:    expected unsigned int
drivers/staging/gdm724x/gdm_endian.c:46:24:    got restricted __be32 [usertype] <noident>
drivers/staging/gdm724x/gdm_endian.c:52:24: warning: cast to restricted __le32
drivers/staging/gdm724x/gdm_endian.c:54:24: warning: cast to restricted __be32
Signed-off-by: Eric S. Stone <esstone@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

drivers/staging/gdm724x/gdm_endian.c

@@ -22,34 +22,34 @@ void gdm_set_endian(struct gdm_endian *ed, u8 dev_endian)
 		ed->dev_ed = ENDIANNESS_LITTLE;
 }
 
-u16 gdm_cpu_to_dev16(struct gdm_endian *ed, u16 x)
+__dev16 gdm_cpu_to_dev16(struct gdm_endian *ed, u16 x)
 {
 	if (ed->dev_ed == ENDIANNESS_LITTLE)
-		return cpu_to_le16(x);
+		return (__force __dev16)cpu_to_le16(x);
 	else
-		return cpu_to_be16(x);
+		return (__force __dev16)cpu_to_be16(x);
 }
 
-u16 gdm_dev16_to_cpu(struct gdm_endian *ed, u16 x)
+u16 gdm_dev16_to_cpu(struct gdm_endian *ed, __dev16 x)
 {
 	if (ed->dev_ed == ENDIANNESS_LITTLE)
-		return le16_to_cpu(x);
+		return le16_to_cpu((__force __le16)x);
 	else
-		return be16_to_cpu(x);
+		return be16_to_cpu((__force __be16)x);
 }
 
-u32 gdm_cpu_to_dev32(struct gdm_endian *ed, u32 x)
+__dev32 gdm_cpu_to_dev32(struct gdm_endian *ed, u32 x)
 {
 	if (ed->dev_ed == ENDIANNESS_LITTLE)
-		return cpu_to_le32(x);
+		return (__force __dev32)cpu_to_le32(x);
 	else
-		return cpu_to_be32(x);
+		return (__force __dev32)cpu_to_be32(x);
 }
 
-u32 gdm_dev32_to_cpu(struct gdm_endian *ed, u32 x)
+u32 gdm_dev32_to_cpu(struct gdm_endian *ed, __dev32 x)
 {
 	if (ed->dev_ed == ENDIANNESS_LITTLE)
-		return le32_to_cpu(x);
+		return le32_to_cpu((__force __le32)x);
 	else
-		return be32_to_cpu(x);
+		return be32_to_cpu((__force __be32)x);
 }

drivers/staging/gdm724x/gdm_endian.h

@@ -16,6 +16,13 @@
 
 #include <linux/types.h>
 
+/*
+ * For data in "device-endian" byte order (device endianness is model
+ * dependent).  Analogous to __leXX or __beXX.
+ */
+typedef __u32 __bitwise __dev32;
+typedef __u16 __bitwise __dev16;
+
 enum {
 	ENDIANNESS_MIN = 0,
 	ENDIANNESS_UNKNOWN,
@@ -30,9 +37,9 @@ struct gdm_endian {
 };
 
 void gdm_set_endian(struct gdm_endian *ed, u8 dev_endian);
-u16 gdm_cpu_to_dev16(struct gdm_endian *ed, u16 x);
-u16 gdm_dev16_to_cpu(struct gdm_endian *ed, u16 x);
-u32 gdm_cpu_to_dev32(struct gdm_endian *ed, u32 x);
-u32 gdm_dev32_to_cpu(struct gdm_endian *ed, u32 x);
+__dev16 gdm_cpu_to_dev16(struct gdm_endian *ed, u16 x);
+u16 gdm_dev16_to_cpu(struct gdm_endian *ed, __dev16 x);
+__dev32 gdm_cpu_to_dev32(struct gdm_endian *ed, u32 x);
+u32 gdm_dev32_to_cpu(struct gdm_endian *ed, __dev32 x);
 
 #endif /*__GDM_ENDIAN_H__*/

drivers/staging/gdm724x/hci_packet.h

@@ -36,8 +36,8 @@
 #define NIC_TYPE_F_VLAN		0x00100000
 
 struct hci_packet {
-	u16 cmd_evt;
-	u16 len;
+	__dev16 cmd_evt;
+	__dev16 len;
 	u8 data[0];
 } __packed;
 
@@ -48,45 +48,45 @@ struct tlv {
 } __packed;
 
 struct sdu_header {
-	u16 cmd_evt;
-	u16 len;
-	u32 dftEpsId;
-	u32 bearer_ID;
-	u32 nic_type;
+	__dev16 cmd_evt;
+	__dev16 len;
+	__dev32 dftEpsId;
+	__dev32 bearer_ID;
+	__dev32 nic_type;
 } __packed;
 
 struct sdu {
-	u16 cmd_evt;
-	u16 len;
-	u32 dft_eps_ID;
-	u32 bearer_ID;
-	u32 nic_type;
+	__dev16 cmd_evt;
+	__dev16 len;
+	__dev32 dft_eps_ID;
+	__dev32 bearer_ID;
+	__dev32 nic_type;
 	u8 data[0];
 } __packed;
 
 struct multi_sdu {
-	u16 cmd_evt;
-	u16 len;
-	u16 num_packet;
-	u16 reserved;
+	__dev16 cmd_evt;
+	__dev16 len;
+	__dev16 num_packet;
+	__dev16 reserved;
 	u8 data[0];
 } __packed;
 
 struct hci_pdn_table_ind {
-	u16 cmd_evt;
-	u16 len;
+	__dev16 cmd_evt;
+	__dev16 len;
 	u8 activate;
-	u32 dft_eps_id;
-	u32 nic_type;
+	__dev32 dft_eps_id;
+	__dev32 nic_type;
 	u8 pdn_type;
 	u8 ipv4_addr[4];
 	u8 ipv6_intf_id[8];
 } __packed;
 
 struct hci_connect_ind {
-	u16 cmd_evt;
-	u16 len;
-	u32 connect;
+	__dev16 cmd_evt;
+	__dev16 len;
+	__dev32 connect;
 } __packed;
 
 #endif /* _HCI_PACKET_H_ */