diff options
Diffstat (limited to 'include/uapi')
| -rw-r--r-- | include/uapi/mtd/mtd-abi.h | 64 |
1 files changed, 59 insertions, 5 deletions
diff --git a/include/uapi/mtd/mtd-abi.h b/include/uapi/mtd/mtd-abi.h index 890d9e5b76d7..714d55b49d2a 100644 --- a/include/uapi/mtd/mtd-abi.h +++ b/include/uapi/mtd/mtd-abi.h @@ -55,9 +55,9 @@ struct mtd_oob_buf64 { * @MTD_OPS_RAW: data are transferred as-is, with no error correction; * this mode implies %MTD_OPS_PLACE_OOB * - * These modes can be passed to ioctl(MEMWRITE) and are also used internally. - * See notes on "MTD file modes" for discussion on %MTD_OPS_RAW vs. - * %MTD_FILE_MODE_RAW. + * These modes can be passed to ioctl(MEMWRITE) and ioctl(MEMREAD); they are + * also used internally. See notes on "MTD file modes" for discussion on + * %MTD_OPS_RAW vs. %MTD_FILE_MODE_RAW. */ enum { MTD_OPS_PLACE_OOB = 0, @@ -91,6 +91,53 @@ struct mtd_write_req { __u8 padding[7]; }; +/** + * struct mtd_read_req_ecc_stats - ECC statistics for a read operation + * + * @uncorrectable_errors: the number of uncorrectable errors that happened + * during the read operation + * @corrected_bitflips: the number of bitflips corrected during the read + * operation + * @max_bitflips: the maximum number of bitflips detected in any single ECC + * step for the data read during the operation; this information + * can be used to decide whether the data stored in a specific + * region of the MTD device should be moved somewhere else to + * avoid data loss. + */ +struct mtd_read_req_ecc_stats { + __u32 uncorrectable_errors; + __u32 corrected_bitflips; + __u32 max_bitflips; +}; + +/** + * struct mtd_read_req - data structure for requesting a read operation + * + * @start: start address + * @len: length of data buffer (only lower 32 bits are used) + * @ooblen: length of OOB buffer (only lower 32 bits are used) + * @usr_data: user-provided data buffer + * @usr_oob: user-provided OOB buffer + * @mode: MTD mode (see "MTD operation modes") + * @padding: reserved, must be set to 0 + * @ecc_stats: ECC statistics for the read operation + * + * This structure supports ioctl(MEMREAD) operations, allowing data and/or OOB + * reads in various modes. To read from OOB-only, set @usr_data == NULL, and to + * read data-only, set @usr_oob == NULL. However, setting both @usr_data and + * @usr_oob to NULL is not allowed. + */ +struct mtd_read_req { + __u64 start; + __u64 len; + __u64 ooblen; + __u64 usr_data; + __u64 usr_oob; + __u8 mode; + __u8 padding[7]; + struct mtd_read_req_ecc_stats ecc_stats; +}; + #define MTD_ABSENT 0 #define MTD_RAM 1 #define MTD_ROM 2 @@ -207,6 +254,12 @@ struct otp_info { #define MEMWRITE _IOWR('M', 24, struct mtd_write_req) /* Erase a given range of user data (must be in mode %MTD_FILE_MODE_OTP_USER) */ #define OTPERASE _IOW('M', 25, struct otp_info) +/* + * Most generic read interface; can read in-band and/or out-of-band in various + * modes (see "struct mtd_read_req"). This ioctl is not supported for flashes + * without OOB, e.g., NOR flash. + */ +#define MEMREAD _IOWR('M', 26, struct mtd_read_req) /* * Obsolete legacy interface. Keep it in order not to break userspace @@ -270,8 +323,9 @@ struct mtd_ecc_stats { * Note: %MTD_FILE_MODE_RAW provides the same functionality as %MTD_OPS_RAW - * raw access to the flash, without error correction or autoplacement schemes. * Wherever possible, the MTD_OPS_* mode will override the MTD_FILE_MODE_* mode - * (e.g., when using ioctl(MEMWRITE)), but in some cases, the MTD_FILE_MODE is - * used out of necessity (e.g., `write()', ioctl(MEMWRITEOOB64)). + * (e.g., when using ioctl(MEMWRITE) or ioctl(MEMREAD)), but in some cases, the + * MTD_FILE_MODE is used out of necessity (e.g., `write()', + * ioctl(MEMWRITEOOB64)). */ enum mtd_file_modes { MTD_FILE_MODE_NORMAL = MTD_OTP_OFF, |