drivers/usb/storage/cypress_atacb.c

Source file repositories/reference/linux-study-clean/drivers/usb/storage/cypress_atacb.c

File Facts

System
Linux kernel
Corpus path
drivers/usb/storage/cypress_atacb.c
Extension
.c
Size
8195 bytes
Lines
287
Domain
Driver Families
Bucket
drivers/usb
Inferred role
Driver Families: implementation source
Status
source implementation candidate

Why This File Exists

Repeatable hardware-adapter layer. Deep compatibility for every driver is out of scope; this atlas records patterns, probe lifecycles, bus glue, IRQ/DMA usage, and links back to core abstractions.

Dependency Surface

Detected Declarations

Annotated Snippet

if (save_cmnd[1] & 0x01) {/* extended bit set for LBA48 */
			/* this could be supported by atacb2 */
			if (save_cmnd[3] || save_cmnd[5] || save_cmnd[7] || save_cmnd[9]
					|| save_cmnd[11])
				goto invalid_fld;
		}
	} else { /* ATA12 */
		srb->cmnd[ 6] = save_cmnd[3]; /* features */
		srb->cmnd[ 7] = save_cmnd[4]; /* sector count */
		srb->cmnd[ 8] = save_cmnd[5]; /* lba low */
		srb->cmnd[ 9] = save_cmnd[6]; /* lba med */
		srb->cmnd[10] = save_cmnd[7]; /* lba high */
		srb->cmnd[11] = save_cmnd[8]; /* device */
		srb->cmnd[12] = save_cmnd[9]; /* command */

	}
	/* Filter SET_FEATURES - XFER MODE command */
	if ((srb->cmnd[12] == ATA_CMD_SET_FEATURES)
			&& (srb->cmnd[6] == SETFEATURES_XFER))
		goto invalid_fld;

	if (srb->cmnd[12] == ATA_CMD_ID_ATA || srb->cmnd[12] == ATA_CMD_ID_ATAPI)
		srb->cmnd[2] |= (1<<7); /* set  IdentifyPacketDevice for these cmds */


	usb_stor_transparent_scsi_command(srb, us);

	/* if the device doesn't support ATACB */
	if (srb->result == SAM_STAT_CHECK_CONDITION &&
			memcmp(srb->sense_buffer, usb_stor_sense_invalidCDB,
				sizeof(usb_stor_sense_invalidCDB)) == 0) {
		usb_stor_dbg(us, "cypress atacb not supported ???\n");
		goto end;
	}

	/*
	 * if ck_cond flags is set, and there wasn't critical error,
	 * build the special sense
	 */
	if ((srb->result != (DID_ERROR << 16) &&
				srb->result != (DID_ABORT << 16)) &&
			save_cmnd[2] & 0x20) {
		struct scsi_eh_save ses;
		unsigned char regs[8];
		unsigned char *sb = srb->sense_buffer;
		unsigned char *desc = sb + 8;
		int tmp_result;

		/* build the command for reading the ATA registers */
		scsi_eh_prep_cmnd(srb, &ses, NULL, 0, sizeof(regs));

		/*
		 * we use the same command as before, but we set
		 * the read taskfile bit, for not executing atacb command,
		 * but reading register selected in srb->cmnd[4]
		 */
		srb->cmd_len = 16;
		srb->cmnd[2] = 1;

		usb_stor_transparent_scsi_command(srb, us);
		memcpy(regs, srb->sense_buffer, sizeof(regs));
		tmp_result = srb->result;
		scsi_eh_restore_cmnd(srb, &ses);
		/* we fail to get registers, report invalid command */
		if (tmp_result != SAM_STAT_GOOD)
			goto invalid_fld;

		/* build the sense */
		memset(sb, 0, SCSI_SENSE_BUFFERSIZE);

		/* set sk, asc for a good command */
		sb[1] = RECOVERED_ERROR;
		sb[2] = 0; /* ATA PASS THROUGH INFORMATION AVAILABLE */
		sb[3] = 0x1D;

		/*
		 * XXX we should generate sk, asc, ascq from status and error
		 * regs
		 * (see 11.1 Error translation ATA device error to SCSI error
		 * map, and ata_to_sense_error from libata.)
		 */

		/* Sense data is current and format is descriptor. */
		sb[0] = 0x72;
		desc[0] = 0x09; /* ATA_RETURN_DESCRIPTOR */

		/* set length of additional sense data */
		sb[7] = 14;
		desc[1] = 12;

Annotation

Implementation Notes