Messages in this thread | | | Date | Sat, 8 Mar 2008 10:31:25 -0800 | From | Matthew Dharm <> | Subject | Re: [PATCH] mass storage : emulation of sat scsi_pass_thru with ATACB |
| |
Why are you using an initializer instead of a new protocol code?
Most of this should probably be moved into it's own file, just like all of the other protocol handlers.
Actually, why do you even have a separate 'dispatcher' function? Why not just one protocol handler function which checks the command at the top and calls invoke_transport there?
Also, unless ATACB is a new standard (and I don't think it is, as the Cypress datasheet uses the term 'vendor specific'), then your functions need renaming. Instead of 'emulate_pass_thru_with_atacb', how about something like 'cypress_atacb' -- since it's already a protocol handler, everyone already knows it's for passing commands.
Matt
On Sat, Mar 08, 2008 at 06:32:05PM +0100, matthieu castet wrote: > Hi, > > I have got a cypress usb-ide bridge and I would like to tune or monitor > my disk with tools like hdparm, hddtemp or smartctl. > > My controller support a way to send raw ATA command to the disk with > something call atacb (see > http://download.cypress.com.edgesuite.net/design_resources/datasheets/contents/cy7c68300c_8.pdf). > > Atacb support can be added for each application, but there is some > disadvantages : > - all application need to be patched > - A race is possible if there other accesses, because the emulation can > be split in 2 atacb scsi transactions. One for sending the command, one > for reading the register (if ck_cond is set). > > I have implemented the emulation in usb-storage with a special > proto_handler, > and an unsual entry. > > Signed-off-by: Matthieu CASTET <castet.matthieu@free.fr> > > Index: linux-2.6.24.2/drivers/usb/storage/protocol.c > =================================================================== > --- linux-2.6.24.2.orig/drivers/usb/storage/protocol.c 2008-02-29 > 22:14:09.000000000 +0100 > +++ linux-2.6.24.2/drivers/usb/storage/protocol.c 2008-03-08 > 18:18:22.000000000 +0100 > @@ -47,6 +47,8 @@ > #include <linux/highmem.h> > #include <scsi/scsi.h> > #include <scsi/scsi_cmnd.h> > +#include <scsi/scsi_eh.h> > +#include <linux/ata.h> > > #include "usb.h" > #include "protocol.h" > @@ -144,6 +146,179 @@ > usb_stor_invoke_transport(srb, us); > } > > +/* > + * ATACB is a protocol used on cypress usb<->ata bridge to > + * send raw ATA command over mass storage > + * There is a ATACB2 protocol that support LBA48 on newer chip. > + * More info that be found on cy7c68310_8.pdf and cy7c68300c_8.pdf > + * datasheet from cypress.com. > + */ > +static void emulate_pass_thru_with_atacb(struct scsi_cmnd *srb, > + struct us_data *us) > +{ > + unsigned char save_cmnd[MAX_COMMAND_SIZE]; > + memcpy(save_cmnd, srb->cmnd, sizeof(save_cmnd)); > + memset(srb->cmnd, 0, sizeof(srb->cmnd)); > + > + /* check if we support the command */ > + if (save_cmnd[1] >> 5) /* MULTIPLE_COUNT */ > + goto invalid_fld; > + /* check protocol */ > + switch((save_cmnd[1] >> 1) & 0xf) { > + case 3: > + case 4: > + case 5: > + break; > + default: > + goto invalid_fld; > + } > + > + /* first build the ATACB command */ > + srb->cmd_len = 16; > + > + /* this value can change, but most(all ?) manufacturers keep the > cypress > + * default : 0x24 > + */ > + srb->cmnd[0] = 0x24; > + srb->cmnd[1] = 0x24; > + srb->cmnd[2] = 0; > + > + srb->cmnd[3] = 0xff - 1; > + srb->cmnd[4] = 1; > + > + if (save_cmnd[0] == ATA_16) { > + srb->cmnd[6] = save_cmnd[4]; /* features */ > + srb->cmnd[7] = save_cmnd[6]; /* sector count */ > + srb->cmnd[8] = save_cmnd[8]; /* lba low */ > + srb->cmnd[9] = save_cmnd[10]; /* lba med */ > + srb->cmnd[10] = save_cmnd[12]; /* lba high */ > + srb->cmnd[11] = save_cmnd[13]; /* device */ > + srb->cmnd[12] = save_cmnd[14]; /* command */ > + > + 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); > + > + > + usb_stor_invoke_transport(srb, us); > + > + /* if the device doesn't support ATACB > + * abort and register usb_stor_transparent_scsi_command > + * callback > + */ > + if (srb->result == SAM_STAT_CHECK_CONDITION && > + memcmp(srb->sense_buffer, usb_stor_sense_invalidCDB, > + sizeof(usb_stor_sense_invalidCDB)) == 0) { > + us->proto_handler = usb_stor_transparent_scsi_command; > + 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 sk, asc, ascq; > + unsigned char regs[8]; > + unsigned char *sb = srb->sense_buffer; > + unsigned char *desc = sb + 8; > + int tmp_result; > + > + sk = RECOVERED_ERROR; > + asc = 0; /* ATA PASS THROUGH INFORMATION AVAILABLE */ > + ascq = 0x1D; > + > + /* read registers */ > + srb->cmnd[2] = 1; > + scsi_eh_prep_cmnd(srb, &ses, NULL, 0, 0); > + srb->request_buffer = regs; > + srb->request_bufflen = sizeof(regs); > + srb->sc_data_direction = DMA_FROM_DEVICE; > + > + usb_stor_invoke_transport(srb, us); > + 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); > + > + /* 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. > + */ > + sb[1] = sk; > + sb[2] = asc; > + sb[3] = ascq; > + > + /* 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; > + > + /* Copy registers into sense buffer. */ > + desc[2] = 0x00; > + desc[3] = regs[1]; > + desc[5] = regs[2]; > + desc[7] = regs[3]; > + desc[9] = regs[4]; > + desc[11] = regs[5]; > + desc[12] = regs[6]; > + desc[13] = regs[7]; > + > + srb->result = (DRIVER_SENSE << 24) | > SAM_STAT_CHECK_CONDITION; > + } > + goto end; > +invalid_fld: > + srb->result = (DRIVER_SENSE << 24) | SAM_STAT_CHECK_CONDITION; > + > + memcpy(srb->sense_buffer, > + usb_stor_sense_invalidCDB, > + sizeof(usb_stor_sense_invalidCDB)); > +end: > + memcpy(srb->cmnd, save_cmnd, sizeof(save_cmnd)); > + if (srb->cmnd[0] == ATA_12) > + srb->cmd_len = 12; > +} > + > +void usb_stor_transparent_scsi_command_atacb(struct scsi_cmnd *srb, > + struct us_data *us) > +{ > + if (srb->cmnd[0] != ATA_16 && srb->cmnd[0] != ATA_12) > + usb_stor_invoke_transport(srb, us); > + else > + emulate_pass_thru_with_atacb(srb, us); > +} > + > /*********************************************************************** > * Scatter-gather transfer buffer access routines > ***********************************************************************/ > Index: linux-2.6.24.2/drivers/usb/storage/initializers.c > =================================================================== > --- linux-2.6.24.2.orig/drivers/usb/storage/initializers.c 2008-02-29 > 22:14:09.000000000 +0100 > +++ linux-2.6.24.2/drivers/usb/storage/initializers.c 2008-03-08 > 18:30:00.000000000 +0100 > @@ -43,6 +43,7 @@ > #include "initializers.h" > #include "debug.h" > #include "transport.h" > +#include "protocol.h" > > /* This places the Shuttle/SCM USB<->SCSI bridge devices in multi-target > * mode */ > @@ -104,3 +105,11 @@ > US_DEBUGP("usb_control_msg performing result is %d\n", result); > return (result ? 0 : -1); > } > + > +/* This function register the atacb proto callback */ > +int usb_atacb_init(struct us_data *us) > +{ > + us->proto_handler = usb_stor_transparent_scsi_command_atacb; > + US_DEBUGP("atacb proto_handler is set\n"); > + return 0; > +} > Index: linux-2.6.24.2/drivers/usb/storage/initializers.h > =================================================================== > --- linux-2.6.24.2.orig/drivers/usb/storage/initializers.h 2008-02-29 > 22:14:09.000000000 +0100 > +++ linux-2.6.24.2/drivers/usb/storage/initializers.h 2008-03-08 > 18:28:33.000000000 +0100 > @@ -50,3 +50,6 @@ > > /* This places the HUAWEI E220 devices in multi-port mode */ > int usb_stor_huawei_e220_init(struct us_data *us); > + > +/* This function register the atacb proto callback */ > +int usb_atacb_init(struct us_data *us); > Index: linux-2.6.24.2/drivers/usb/storage/protocol.h > =================================================================== > --- linux-2.6.24.2.orig/drivers/usb/storage/protocol.h 2008-02-29 > 22:14:09.000000000 +0100 > +++ linux-2.6.24.2/drivers/usb/storage/protocol.h 2008-02-29 > 22:16:03.000000000 +0100 > @@ -47,6 +47,8 @@ > extern void usb_stor_ufi_command(struct scsi_cmnd*, struct us_data*); > extern void usb_stor_transparent_scsi_command(struct scsi_cmnd*, > struct us_data*); > +extern void usb_stor_transparent_scsi_command_atacb(struct scsi_cmnd*, > + struct us_data*); > > /* struct scsi_cmnd transfer buffer access utilities */ > enum xfer_buf_dir {TO_XFER_BUF, FROM_XFER_BUF}; > Index: linux-2.6.24.2/drivers/usb/storage/unusual_devs.h > =================================================================== > --- linux-2.6.24.2.orig/drivers/usb/storage/unusual_devs.h 2008-02-29 > 22:14:09.000000000 +0100 > +++ linux-2.6.24.2/drivers/usb/storage/unusual_devs.h 2008-02-29 > 22:16:03.000000000 +0100 > @@ -1588,6 +1588,12 @@ > US_SC_DEVICE, US_PR_DEVICE, NULL, > US_FL_CAPACITY_HEURISTICS), > > +UNUSUAL_DEV( 0x04b4, 0x6830, 0x0000, 0x9999, > + "Cypress", > + "Cypress AT2LP", > + US_SC_SCSI, US_PR_BULK, usb_atacb_init, > + US_FL_NEED_OVERRIDE), > + > /* Control/Bulk transport for all SubClass values */ > USUAL_DEV(US_SC_RBC, US_PR_CB, USB_US_TYPE_STOR), > USUAL_DEV(US_SC_8020, US_PR_CB, USB_US_TYPE_STOR), > -- > To unsubscribe from this list: send the line "unsubscribe linux-usb" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html
-- Matthew Dharm Home: mdharm-usb@one-eyed-alien.net Maintainer, Linux USB Mass Storage Driver
A: The most ironic oxymoron wins ... DP: "Microsoft Works" A: Uh, okay, you win. -- A.J. & Dust Puppy User Friendly, 1/18/1998 [unhandled content-type:application/pgp-signature] | |