/*- * Copyright (c) 2001,2002 Thomas Quinot * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer, * without modification, immediately at the beginning of the file. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. The name of the author may not be used to endorse or promote products * derived from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * $FreeBSD: src/sys/dev/ata/atapi-cam.c,v 1.10.2.3 2003/05/21 09:24:55 thomas Exp $ * $DragonFly: src/sys/dev/disk/ata/atapi-cam.c,v 1.4 2003/11/30 20:14:18 dillon Exp $ */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "ata-all.h" #include "atapi-all.h" /* hardware command descriptor block */ struct atapi_hcb { struct atapi_xpt_softc *softc; int unit; int bus; int target; int lun; union ccb *ccb; u_int8_t cmd[CAM_MAX_CDBLEN]; int flags; #define DOING_AUTOSENSE 1 char *dxfer_alloc; TAILQ_ENTRY(atapi_hcb) chain; }; /* private data associated with an ATA bus */ struct atapi_xpt_softc { struct ata_channel *ata_ch; struct cam_path *path; struct cam_sim *sim; int flags; #define BUS_REGISTERED 0x01 #define RESOURCE_SHORTAGE 0x02 TAILQ_HEAD(,atapi_hcb) pending_hcbs; LIST_ENTRY(atapi_xpt_softc) chain; }; enum reinit_reason { BOOT_ATTACH, ATTACH, RESET }; static LIST_HEAD(,atapi_xpt_softc) all_buses = LIST_HEAD_INITIALIZER(all_buses); /* CAM XPT methods */ static void atapi_action(struct cam_sim *, union ccb *); static void atapi_poll(struct cam_sim *); static void atapi_async(void *, u_int32_t, struct cam_path *, void *); static void atapi_async1(void *, u_int32_t, struct cam_path *, void *); static int atapi_cb(struct atapi_request *); /* internal functions */ static void reinit_bus(struct atapi_xpt_softc *scp, enum reinit_reason reason); static void setup_dev(struct atapi_xpt_softc *, struct ata_device *); static void setup_async_cb(struct atapi_xpt_softc *, uint32_t); static void cam_rescan_callback(struct cam_periph *, union ccb *); static void cam_rescan(struct cam_sim *); static void free_hcb_and_ccb_done(struct atapi_hcb *, u_int32_t); static struct atapi_hcb *allocate_hcb(struct atapi_xpt_softc *, int, int, union ccb *); static void free_hcb(struct atapi_hcb *hcb); static void free_softc(struct atapi_xpt_softc *scp); static struct atapi_xpt_softc *get_softc(struct ata_channel *ata_ch); static struct ata_device *get_ata_device(struct atapi_xpt_softc *scp, int id); static MALLOC_DEFINE(M_ATACAM, "ATA CAM transport", "ATA driver CAM-XPT layer"); void atapi_cam_attach_bus(struct ata_channel *ata_ch) { struct atapi_xpt_softc *scp = NULL; struct cam_devq *devq = NULL; struct cam_sim *sim = NULL; struct cam_path *path = NULL; int unit; LIST_FOREACH(scp, &all_buses, chain) { if (scp->ata_ch == ata_ch) return; } if ((scp = malloc(sizeof(struct atapi_xpt_softc), M_ATACAM, M_WAITOK | M_ZERO)) == NULL) goto error; scp->ata_ch = ata_ch; TAILQ_INIT(&scp->pending_hcbs); LIST_INSERT_HEAD(&all_buses, scp, chain); unit = device_get_unit(ata_ch->dev); if ((devq = cam_simq_alloc(16)) == NULL) goto error; if ((sim = cam_sim_alloc(atapi_action, atapi_poll, "ata", (void *)scp, unit, 1, 1, devq)) == NULL) { cam_simq_free(devq); goto error; } scp->sim = sim; if (xpt_bus_register(sim, 0) != CAM_SUCCESS) { goto error; } scp->flags |= BUS_REGISTERED; if (xpt_create_path(&path, /*periph*/ NULL, cam_sim_path(sim), CAM_TARGET_WILDCARD, CAM_LUN_WILDCARD) != CAM_REQ_CMP) { goto error; } scp->path = path; CAM_DEBUG(path, CAM_DEBUG_TRACE, ("Registered SIM for ata%d\n", unit)); setup_async_cb(scp, AC_LOST_DEVICE); reinit_bus(scp, cold ? BOOT_ATTACH : ATTACH); return; error: free_softc(scp); } void atapi_cam_detach_bus(struct ata_channel *ata_ch) { struct atapi_xpt_softc *scp = get_softc(ata_ch); free_softc(scp); } void atapi_cam_reinit_bus(struct ata_channel *ata_ch) { struct atapi_xpt_softc *scp = get_softc(ata_ch); /* * scp might be null if the bus is being reinitialised during * the boot-up sequence, before the ATAPI bus is registered. */ if (scp != NULL) reinit_bus(scp, RESET); } static void reinit_bus(struct atapi_xpt_softc *scp, enum reinit_reason reason) { if (scp->ata_ch->devices & ATA_ATAPI_MASTER) setup_dev(scp, &scp->ata_ch->device[MASTER]); if (scp->ata_ch->devices & ATA_ATAPI_SLAVE) setup_dev(scp, &scp->ata_ch->device[SLAVE]); switch (reason) { case BOOT_ATTACH: break; case RESET: xpt_async(AC_BUS_RESET, scp->path, NULL); /*FALLTHROUGH*/ case ATTACH: cam_rescan(scp->sim); break; } } static void setup_dev(struct atapi_xpt_softc *scp, struct ata_device *atp) { if (atp->driver == NULL) { ata_set_name(atp, "atapicam", 2 * device_get_unit(atp->channel->dev) + (atp->unit == ATA_MASTER) ? 0 : 1); atp->driver = (void *)scp; } } static void setup_async_cb(struct atapi_xpt_softc *scp, uint32_t events) { struct ccb_setasync csa; xpt_setup_ccb(&csa.ccb_h, scp->path, /*priority*/ 5); csa.ccb_h.func_code = XPT_SASYNC_CB; csa.event_enable = events; csa.callback = &atapi_async; csa.callback_arg = scp->sim; xpt_action((union ccb *) &csa); } static void atapi_action(struct cam_sim *sim, union ccb *ccb) { struct atapi_xpt_softc *softc = (struct atapi_xpt_softc*)cam_sim_softc(sim); struct ccb_hdr *ccb_h = &ccb->ccb_h; struct atapi_hcb *hcb = NULL; int unit = cam_sim_unit(sim); int bus = cam_sim_bus(sim); int len, s; char *buf; switch (ccb_h->func_code) { case XPT_PATH_INQ: { struct ccb_pathinq *cpi = &ccb->cpi; cpi->version_num = 1; cpi->hba_inquiry = 0; cpi->target_sprt = 0; cpi->hba_misc = 0; cpi->hba_eng_cnt = 0; bzero(cpi->vuhba_flags, sizeof(cpi->vuhba_flags)); cpi->max_target = 1; cpi->max_lun = 0; cpi->async_flags = 0; cpi->hpath_id = 0; cpi->initiator_id = 7; strncpy(cpi->sim_vid, "FreeBSD", sizeof(cpi->sim_vid)); strncpy(cpi->hba_vid, "ATAPI", sizeof(cpi->hba_vid)); strncpy(cpi->dev_name, cam_sim_name(sim), sizeof cpi->dev_name); cpi->unit_number = cam_sim_unit(sim); cpi->bus_id = cam_sim_bus(sim); if (softc->ata_ch && ccb_h->target_id >= 0) { switch (softc->ata_ch->device[ccb_h->target_id].mode) { case ATA_PIO1: cpi->base_transfer_speed = 5200; break; case ATA_PIO2: cpi->base_transfer_speed = 7000; break; case ATA_PIO3: cpi->base_transfer_speed = 11000; break; case ATA_PIO4: case ATA_DMA: case ATA_WDMA2: cpi->base_transfer_speed = 16000; break; case ATA_UDMA2: cpi->base_transfer_speed = 33000; break; case ATA_UDMA4: cpi->base_transfer_speed = 66000; break; case ATA_UDMA5: cpi->base_transfer_speed = 100000; break; case ATA_UDMA6: cpi->base_transfer_speed = 133000; break; default: cpi->base_transfer_speed = 3300; } } ccb->ccb_h.status = CAM_REQ_CMP; xpt_done(ccb); return; } case XPT_RESET_DEV: { int tid = ccb_h->target_id; struct ata_device *dev = get_ata_device(softc, tid); CAM_DEBUG(ccb->ccb_h.path, CAM_DEBUG_SUBTRACE, ("dev reset\n")); atapi_reinit(dev); ccb->ccb_h.status = CAM_REQ_CMP; xpt_done(ccb); return; } case XPT_RESET_BUS: CAM_DEBUG(ccb->ccb_h.path, CAM_DEBUG_SUBTRACE, ("bus reset\n")); ata_reinit(softc->ata_ch); ccb->ccb_h.status = CAM_REQ_CMP; xpt_done(ccb); return; case XPT_SET_TRAN_SETTINGS: /* ignore these, we're not doing SCSI here */ CAM_DEBUG(ccb->ccb_h.path, CAM_DEBUG_SUBTRACE, ("SET_TRAN_SETTINGS not supported\n")); ccb->ccb_h.status = CAM_FUNC_NOTAVAIL; xpt_done(ccb); return; case XPT_GET_TRAN_SETTINGS: { struct ccb_trans_settings *cts = &ccb->cts; /* * XXX The default CAM transport code is very scsi specific and * doesn't understand IDE speeds very well. Be silent about it * here and let it default to what is set in XPT_PATH_INQ */ CAM_DEBUG(ccb->ccb_h.path, CAM_DEBUG_SUBTRACE, ("GET_TRAN_SETTINGS\n")); cts->valid = (CCB_TRANS_DISC_VALID | CCB_TRANS_TQ_VALID); cts->flags &= ~(CCB_TRANS_DISC_ENB | CCB_TRANS_TAG_ENB); ccb->ccb_h.status = CAM_REQ_CMP; xpt_done(ccb); return; } case XPT_CALC_GEOMETRY: { struct ccb_calc_geometry *ccg; unsigned int size_mb; unsigned int secs_per_cylinder; int extended; CAM_DEBUG(ccb->ccb_h.path, CAM_DEBUG_SUBTRACE, ("CALC_GEOMETRY\n")); ccg = &ccb->ccg; size_mb = ccg->volume_size / ((1024L * 1024L) / ccg->block_size); extended = 1; if (size_mb > 1024 && extended) { ccg->heads = 255; ccg->secs_per_track = 63; } else { ccg->heads = 64; ccg->secs_per_track = 32; } secs_per_cylinder = ccg->heads * ccg->secs_per_track; ccg->cylinders = ccg->volume_size / secs_per_cylinder; ccb->ccb_h.status = CAM_REQ_CMP; xpt_done(ccb); return; } case XPT_SCSI_IO: { struct ccb_scsiio *csio = &ccb->csio; int tid = ccb_h->target_id, lid = ccb_h->target_lun; struct ata_device *dev = get_ata_device(softc, tid); CAM_DEBUG(ccb_h->path, CAM_DEBUG_SUBTRACE, ("XPT_SCSI_IO\n")); /* check that this request was not aborted already */ if ((ccb_h->status & CAM_STATUS_MASK) != CAM_REQ_INPROG) { printf("XPT_SCSI_IO received but already in progress?\n"); xpt_done(ccb); return; } if (dev == NULL) { CAM_DEBUG(ccb_h->path, CAM_DEBUG_SUBTRACE, ("SCSI IO received for invalid device\n")); ccb_h->status = CAM_TID_INVALID; xpt_done(ccb); return; } if (lid > 0) { CAM_DEBUG(ccb_h->path, CAM_DEBUG_SUBTRACE, ("SCSI IO received for invalid lun %d\n", lid)); ccb_h->status = CAM_LUN_INVALID; xpt_done(ccb); return; } if ((ccb_h->flags & CAM_SCATTER_VALID)) { /* scatter-gather not supported */ xpt_print_path(ccb_h->path); printf("ATAPI-CAM does not support scatter-gather yet!\n"); break; } if ((hcb = allocate_hcb(softc, unit, bus, ccb)) == NULL) goto action_oom; ccb_h->status |= CAM_SIM_QUEUED; bcopy((ccb_h->flags & CAM_CDB_POINTER) ? csio->cdb_io.cdb_ptr : csio->cdb_io.cdb_bytes, hcb->cmd, csio->cdb_len); #ifdef CAMDEBUG if (CAM_DEBUGGED(ccb_h->path, CAM_DEBUG_CDB)) { char cdb_str[(SCSI_MAX_CDBLEN * 3) + 1]; printf("atapi_action: hcb@%p: %s\n", hcb, scsi_cdb_string(hcb->cmd, cdb_str, sizeof(cdb_str))); } #endif len = csio->dxfer_len; buf = csio->data_ptr; /* some SCSI commands require special processing */ switch (hcb->cmd[0]) { case INQUIRY: { /* * many ATAPI devices seem to report more than * SHORT_INQUIRY_LENGTH bytes of available INQUIRY * information, but respond with some incorrect condition * when actually asked for it, so we are going to pretend * that only SHORT_INQUIRY_LENGTH are expected, anyway. */ struct scsi_inquiry *inq = (struct scsi_inquiry *) &hcb->cmd[0]; if (inq->byte2 == 0 && inq->page_code == 0 && inq->length > SHORT_INQUIRY_LENGTH) { bzero(buf, len); len = inq->length = SHORT_INQUIRY_LENGTH; } break; } case MODE_SELECT_6: /* FALLTHROUGH */ case MODE_SENSE_6: /* * not supported by ATAPI/MMC devices (per SCSI MMC spec) * translate to _10 equivalent. * (actually we should do this only if we have tried * MODE_foo_6 and received ILLEGAL_REQUEST or * INVALID COMMAND OPERATION CODE) * alternative fix: behave like a honest CAM transport, * do not muck with CDB contents, and change scsi_cd to * always use MODE_SENSE_10 in cdgetmode(), or let scsi_cd * know that this specific unit is an ATAPI/MMC one, * and in /that case/ use MODE_SENSE_10 */ CAM_DEBUG(ccb_h->path, CAM_DEBUG_SUBTRACE, ("Translating %s into _10 equivalent\n", (hcb->cmd[0] == MODE_SELECT_6) ? "MODE_SELECT_6" : "MODE_SENSE_6")); hcb->cmd[0] |= 0x40; hcb->cmd[6] = 0; hcb->cmd[7] = 0; hcb->cmd[8] = hcb->cmd[4]; hcb->cmd[9] = hcb->cmd[5]; hcb->cmd[4] = 0; hcb->cmd[5] = 0; break; case READ_6: /* FALLTHROUGH */ case WRITE_6: CAM_DEBUG(ccb_h->path, CAM_DEBUG_SUBTRACE, ("Translating %s into _10 equivalent\n", (hcb->cmd[0] == READ_6) ? "READ_6" : "WRITE_6")); hcb->cmd[0] |= 0x20; hcb->cmd[9] = hcb->cmd[5]; hcb->cmd[8] = hcb->cmd[4]; hcb->cmd[7] = 0; hcb->cmd[6] = 0; hcb->cmd[5] = hcb->cmd[3]; hcb->cmd[4] = hcb->cmd[2]; hcb->cmd[3] = hcb->cmd[1] & 0x1f; hcb->cmd[2] = 0; hcb->cmd[1] = 0; break; } if ((ccb_h->flags & CAM_DIR_MASK) == CAM_DIR_IN && (len & 1)) { /* ATA always transfers an even number of bytes */ if (!(buf = hcb->dxfer_alloc = malloc(++len, M_ATACAM, M_WAITOK | M_ZERO))) goto action_oom; } s = splbio(); TAILQ_INSERT_TAIL(&softc->pending_hcbs, hcb, chain); splx(s); if (atapi_queue_cmd(dev, hcb->cmd, buf, len, (((ccb_h->flags & CAM_DIR_MASK) == CAM_DIR_IN) ? ATPR_F_READ : 0) | ATPR_F_QUIET, ccb_h->timeout, atapi_cb, (void *)hcb) == 0) return; break; } default: CAM_DEBUG(ccb_h->path, CAM_DEBUG_SUBTRACE, ("unsupported function code 0x%02x\n", ccb_h->func_code)); ccb_h->status = CAM_REQ_INVALID; xpt_done(ccb); return; } action_oom: if (hcb != NULL) free_hcb(hcb); xpt_print_path(ccb_h->path); printf("out of memory, freezing queue.\n"); softc->flags |= RESOURCE_SHORTAGE; xpt_freeze_simq(sim, /*count*/ 1); ccb_h->status = CAM_REQUEUE_REQ; xpt_done(ccb); } static void atapi_poll(struct cam_sim *sim) { /* do nothing - we do not actually service any interrupts */ printf("atapi_poll called!\n"); } static int atapi_cb(struct atapi_request *req) { struct atapi_hcb *hcb = (struct atapi_hcb *) req->driver; struct ccb_scsiio *csio = &hcb->ccb->csio; int hcb_status = req->result; int s = splbio(); #ifdef CAMDEBUG if (CAM_DEBUGGED(csio->ccb_h.path, CAM_DEBUG_CDB)) { printf("atapi_cb: hcb@%p status = %02x: (sk = %02x%s%s%s)\n", hcb, hcb_status, hcb_status >> 4, (hcb_status & 4) ? " ABRT" : "", (hcb_status & 2) ? " EOM" : "", (hcb_status & 1) ? " ILI" : ""); printf(" %s: cmd %02x - sk=%02x asc=%02x ascq=%02x\n", req->device->name, req->ccb[0], req->sense.sense_key, req->sense.asc, req->sense.ascq); } #endif if (hcb_status != 0) { csio->scsi_status = SCSI_STATUS_CHECK_COND; if ((csio->ccb_h.flags & CAM_DIS_AUTOSENSE) == 0) { csio->ccb_h.status |= CAM_AUTOSNS_VALID; bcopy((void *)&req->sense, (void *)&csio->sense_data, sizeof(struct atapi_reqsense)); } free_hcb_and_ccb_done(hcb, CAM_SCSI_STATUS_ERROR); } else { if (((csio->ccb_h.flags & CAM_DIR_MASK) == CAM_DIR_IN) && hcb->dxfer_alloc != NULL) bcopy(hcb->dxfer_alloc, csio->data_ptr, csio->dxfer_len); csio->scsi_status = SCSI_STATUS_OK; free_hcb_and_ccb_done(hcb, CAM_REQ_CMP); } splx(s); return 0; } static void free_hcb_and_ccb_done(struct atapi_hcb *hcb, u_int32_t status) { struct atapi_xpt_softc *softc = hcb->softc; union ccb *ccb = hcb->ccb; if (hcb != NULL) { /* we're about to free a hcb, so the shortage has ended */ if (softc->flags & RESOURCE_SHORTAGE) { softc->flags &= ~RESOURCE_SHORTAGE; status |= CAM_RELEASE_SIMQ; } free_hcb(hcb); } ccb->ccb_h.status = status | (ccb->ccb_h.status & ~(CAM_STATUS_MASK | CAM_SIM_QUEUED)); xpt_done(ccb); } static void atapi_async(void *callback_arg, u_int32_t code, struct cam_path *path, void *arg) { int s = splbio(); atapi_async1(callback_arg, code, path, arg); splx(s); } static void atapi_async1(void *callback_arg, u_int32_t code, struct cam_path* path, void *arg) { struct atapi_xpt_softc *softc; struct cam_sim *sim; int targ; sim = (struct cam_sim *) callback_arg; softc = (struct atapi_xpt_softc *) cam_sim_softc(sim); switch (code) { case AC_LOST_DEVICE: targ = xpt_path_target_id(path); xpt_print_path(path); if (targ == -1) printf("Lost host adapter\n"); else printf("Lost target %d???\n", targ); break; default: break; } } static void cam_rescan_callback(struct cam_periph *periph, union ccb *ccb) { if (ccb->ccb_h.status != CAM_REQ_CMP) { CAM_DEBUG(ccb->ccb_h.path, CAM_DEBUG_TRACE, ("Rescan failed, 0x%04x\n", ccb->ccb_h.status)); } else { CAM_DEBUG(ccb->ccb_h.path, CAM_DEBUG_TRACE, ("Rescan succeeded\n")); } xpt_free_path(ccb->ccb_h.path); free(ccb, M_ATACAM); } static void cam_rescan(struct cam_sim *sim) { struct cam_path *path; union ccb *ccb = malloc(sizeof(union ccb), M_ATACAM, M_WAITOK | M_ZERO); if (xpt_create_path(&path, xpt_periph, cam_sim_path(sim), CAM_TARGET_WILDCARD, CAM_LUN_WILDCARD) != CAM_REQ_CMP) return; CAM_DEBUG(ccb->ccb_h.path, CAM_DEBUG_TRACE, ("Rescanning ATAPI bus.\n")); xpt_setup_ccb(&ccb->ccb_h, path, 5/*priority (low)*/); ccb->ccb_h.func_code = XPT_SCAN_BUS; ccb->ccb_h.cbfcnp = cam_rescan_callback; ccb->crcn.flags = CAM_FLAG_NONE; xpt_action(ccb); /* scan is in progress now */ } static struct atapi_hcb * allocate_hcb(struct atapi_xpt_softc *softc, int unit, int bus, union ccb *ccb) { struct atapi_hcb *hcb = (struct atapi_hcb *) malloc(sizeof(struct atapi_hcb), M_ATACAM, M_WAITOK | M_ZERO); if (hcb != NULL) { hcb->softc = softc; hcb->unit = unit; hcb->bus = bus; hcb->ccb = ccb; } return hcb; } static void free_hcb(struct atapi_hcb *hcb) { TAILQ_REMOVE(&hcb->softc->pending_hcbs, hcb, chain); if (hcb->dxfer_alloc != NULL) free(hcb->dxfer_alloc, M_ATACAM); free(hcb, M_ATACAM); } static void free_softc(struct atapi_xpt_softc *scp) { struct atapi_hcb *hcb; if (scp != NULL) { TAILQ_FOREACH(hcb, &scp->pending_hcbs, chain) { free_hcb_and_ccb_done(hcb, CAM_UNREC_HBA_ERROR); } if (scp->path != NULL) { setup_async_cb(scp, 0); xpt_free_path(scp->path); } if ((scp->flags & BUS_REGISTERED) != 0) { if (xpt_bus_deregister(cam_sim_path(scp->sim)) == CAM_REQ_CMP) scp->flags &= ~BUS_REGISTERED; } if (scp->sim != NULL) { if ((scp->flags & BUS_REGISTERED) == 0) cam_sim_free(scp->sim, /*free_devq*/TRUE); else printf("Can't free %s SIM (still registered)\n", cam_sim_name(scp->sim)); } LIST_REMOVE(scp, chain); free(scp, M_ATACAM); } } static struct atapi_xpt_softc * get_softc(struct ata_channel *ata_ch) { struct atapi_xpt_softc *scp; LIST_FOREACH(scp, &all_buses, chain) { if (scp->ata_ch == ata_ch) return scp; } return NULL; } static struct ata_device * get_ata_device(struct atapi_xpt_softc *scp, int id) { int role = ATA_ATAPI_MASTER; switch (id) { case 1: role = ATA_ATAPI_SLAVE; /* FALLTHROUGH */ case 0: if (scp->ata_ch->devices & role) return &scp->ata_ch->device[id]; /* FALLTHROUGH */ default: return NULL; } }