diff options
Diffstat (limited to 'include/linux/usb/ch9.h')
| -rw-r--r-- | include/linux/usb/ch9.h | 57 |
1 files changed, 37 insertions, 20 deletions
diff --git a/include/linux/usb/ch9.h b/include/linux/usb/ch9.h index ae7833749fa2..6169438ec5a2 100644 --- a/include/linux/usb/ch9.h +++ b/include/linux/usb/ch9.h @@ -1,8 +1,9 @@ /* - * This file holds USB constants and structures that are needed for USB - * device APIs. These are used by the USB device model, which is defined - * in chapter 9 of the USB 2.0 specification. Linux has several APIs in C - * that need these: + * This file holds USB constants and structures that are needed for + * USB device APIs. These are used by the USB device model, which is + * defined in chapter 9 of the USB 2.0 specification and in the + * Wireless USB 1.0 (spread around). Linux has several APIs in C that + * need these: * * - the master/host side Linux-USB kernel driver API; * - the "usbfs" user space API; and @@ -14,6 +15,19 @@ * * There's also "Wireless USB", using low power short range radios for * peripheral interconnection but otherwise building on the USB framework. + * + * Note all descriptors are declared '__attribute__((packed))' so that: + * + * [a] they never get padded, either internally (USB spec writers + * probably handled that) or externally; + * + * [b] so that accessing bigger-than-a-bytes fields will never + * generate bus errors on any platform, even when the location of + * its descriptor inside a bundle isn't "naturally aligned", and + * + * [c] for consistency, removing all doubt even when it appears to + * someone that the two other points are non-issues for that + * particular descriptor type. */ #ifndef __LINUX_USB_CH9_H @@ -167,12 +181,15 @@ struct usb_ctrlrequest { #define USB_DT_WIRE_ADAPTER 0x21 #define USB_DT_RPIPE 0x22 -/* conventional codes for class-specific descriptors */ -#define USB_DT_CS_DEVICE 0x21 -#define USB_DT_CS_CONFIG 0x22 -#define USB_DT_CS_STRING 0x23 -#define USB_DT_CS_INTERFACE 0x24 -#define USB_DT_CS_ENDPOINT 0x25 +/* Conventional codes for class-specific descriptors. The convention is + * defined in the USB "Common Class" Spec (3.11). Individual class specs + * are authoritative for their usage, not the "common class" writeup. + */ +#define USB_DT_CS_DEVICE (USB_TYPE_CLASS | USB_DT_DEVICE) +#define USB_DT_CS_CONFIG (USB_TYPE_CLASS | USB_DT_CONFIG) +#define USB_DT_CS_STRING (USB_TYPE_CLASS | USB_DT_STRING) +#define USB_DT_CS_INTERFACE (USB_TYPE_CLASS | USB_DT_INTERFACE) +#define USB_DT_CS_ENDPOINT (USB_TYPE_CLASS | USB_DT_ENDPOINT) /* All standard descriptors have these 2 fields at the beginning */ struct usb_descriptor_header { @@ -367,7 +384,7 @@ struct usb_debug_descriptor { /* bulk endpoints with 8 byte maxpacket */ __u8 bDebugInEndpoint; __u8 bDebugOutEndpoint; -}; +} __attribute__((packed)); /*-------------------------------------------------------------------------*/ @@ -396,7 +413,7 @@ struct usb_security_descriptor { __le16 wTotalLength; __u8 bNumEncryptionTypes; -}; +} __attribute__((packed)); /*-------------------------------------------------------------------------*/ @@ -410,7 +427,7 @@ struct usb_key_descriptor { __u8 tTKID[3]; __u8 bReserved; __u8 bKeyData[0]; -}; +} __attribute__((packed)); /*-------------------------------------------------------------------------*/ @@ -426,7 +443,7 @@ struct usb_encryption_descriptor { #define USB_ENC_TYPE_RSA_1 3 /* rsa3072/sha1 auth */ __u8 bEncryptionValue; /* use in SET_ENCRYPTION */ __u8 bAuthKeyIndex; -}; +} __attribute__((packed)); /*-------------------------------------------------------------------------*/ @@ -438,7 +455,7 @@ struct usb_bos_descriptor { __le16 wTotalLength; __u8 bNumDeviceCaps; -}; +} __attribute__((packed)); /*-------------------------------------------------------------------------*/ @@ -447,7 +464,7 @@ struct usb_dev_cap_header { __u8 bLength; __u8 bDescriptorType; __u8 bDevCapabilityType; -}; +} __attribute__((packed)); #define USB_CAP_TYPE_WIRELESS_USB 1 @@ -475,7 +492,7 @@ struct usb_wireless_cap_descriptor { /* Ultra Wide Band */ __u8 bmFFITXPowerInfo; /* FFI power levels */ __le16 bmBandGroup; __u8 bReserved; -}; +} __attribute__((packed)); /*-------------------------------------------------------------------------*/ @@ -496,7 +513,7 @@ struct usb_wireless_ep_comp_descriptor { #define USB_ENDPOINT_SWITCH_NO 0 #define USB_ENDPOINT_SWITCH_SWITCH 1 #define USB_ENDPOINT_SWITCH_SCALE 2 -}; +} __attribute__((packed)); /*-------------------------------------------------------------------------*/ @@ -512,7 +529,7 @@ struct usb_handshake { __u8 CDID[16]; __u8 nonce[16]; __u8 MIC[8]; -}; +} __attribute__((packed)); /*-------------------------------------------------------------------------*/ @@ -524,7 +541,7 @@ struct usb_connection_context { __u8 CHID[16]; /* persistent host id */ __u8 CDID[16]; /* device id (unique w/in host context) */ __u8 CK[16]; /* connection key */ -}; +} __attribute__((packed)); /*-------------------------------------------------------------------------*/ |