--- /dev/null
+/*
+ * ide-acpi.c
+ * Provides ACPI support for IDE drives.
+ *
+ * Copyright (C) 2005 Intel Corp.
+ * Copyright (C) 2005 Randy Dunlap
+ * Copyright (C) 2006 SUSE Linux Products GmbH
+ * Copyright (C) 2006 Hannes Reinecke
+ */
+
+#include <linux/ata.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <acpi/acpi.h>
+#include <linux/ide.h>
+#include <linux/pci.h>
+
+#include <acpi/acpi_bus.h>
+#include <acpi/acnames.h>
+#include <acpi/acnamesp.h>
+#include <acpi/acparser.h>
+#include <acpi/acexcep.h>
+#include <acpi/acmacros.h>
+#include <acpi/actypes.h>
+
+#define REGS_PER_GTF 7
+struct taskfile_array {
+ u8 tfa[REGS_PER_GTF]; /* regs. 0x1f1 - 0x1f7 */
+};
+
+struct GTM_buffer {
+ u32 PIO_speed0;
+ u32 DMA_speed0;
+ u32 PIO_speed1;
+ u32 DMA_speed1;
+ u32 GTM_flags;
+};
+
+struct ide_acpi_drive_link {
+ ide_drive_t *drive;
+ acpi_handle obj_handle;
+ u8 idbuff[512];
+};
+
+struct ide_acpi_hwif_link {
+ ide_hwif_t *hwif;
+ acpi_handle obj_handle;
+ struct GTM_buffer gtm;
+ struct ide_acpi_drive_link master;
+ struct ide_acpi_drive_link slave;
+};
+
+#undef DEBUGGING
+/* note: adds function name and KERN_DEBUG */
+#ifdef DEBUGGING
+#define DEBPRINT(fmt, args...) \
+ printk(KERN_DEBUG "%s: " fmt, __FUNCTION__, ## args)
+#else
+#define DEBPRINT(fmt, args...) do {} while (0)
+#endif /* DEBUGGING */
+
+extern int ide_noacpi;
+extern int ide_noacpitfs;
+extern int ide_noacpionboot;
+
+/**
+ * ide_get_dev_handle - finds acpi_handle and PCI device.function
+ * @dev: device to locate
+ * @handle: returned acpi_handle for @dev
+ * @pcidevfn: return PCI device.func for @dev
+ *
+ * Returns the ACPI object handle to the corresponding PCI device.
+ *
+ * Returns 0 on success, <0 on error.
+ */
+static int ide_get_dev_handle(struct device *dev, acpi_handle *handle,
+ acpi_integer *pcidevfn)
+{
+ struct pci_dev *pdev = to_pci_dev(dev);
+ unsigned int bus, devnum, func;
+ acpi_integer addr;
+ acpi_handle dev_handle;
+ struct acpi_buffer buffer = {.length = ACPI_ALLOCATE_BUFFER,
+ .pointer = NULL};
+ acpi_status status;
+ struct acpi_device_info *dinfo = NULL;
+ int ret = -ENODEV;
+
+ bus = pdev->bus->number;
+ devnum = PCI_SLOT(pdev->devfn);
+ func = PCI_FUNC(pdev->devfn);
+ /* ACPI _ADR encoding for PCI bus: */
+ addr = (acpi_integer)(devnum << 16 | func);
+
+ DEBPRINT("ENTER: pci %02x:%02x.%01x\n", bus, devnum, func);
+
+ dev_handle = DEVICE_ACPI_HANDLE(dev);
+ if (!dev_handle) {
+ DEBPRINT("no acpi handle for device\n");
+ goto err;
+ }
+
+ status = acpi_get_object_info(dev_handle, &buffer);
+ if (ACPI_FAILURE(status)) {
+ DEBPRINT("get_object_info for device failed\n");
+ goto err;
+ }
+ dinfo = buffer.pointer;
+ if (dinfo && (dinfo->valid & ACPI_VALID_ADR) &&
+ dinfo->address == addr) {
+ *pcidevfn = addr;
+ *handle = dev_handle;
+ } else {
+ DEBPRINT("get_object_info for device has wrong "
+ " address: %llu, should be %u\n",
+ dinfo ? (unsigned long long)dinfo->address : -1ULL,
+ (unsigned int)addr);
+ goto err;
+ }
+
+ DEBPRINT("for dev=0x%x.%x, addr=0x%llx, *handle=0x%p\n",
+ devnum, func, (unsigned long long)addr, *handle);
+ ret = 0;
+err:
+ kfree(dinfo);
+ return ret;
+}
+
+/**
+ * ide_acpi_hwif_get_handle - Get ACPI object handle for a given hwif
+ * @hwif: device to locate
+ *
+ * Retrieves the object handle for a given hwif.
+ *
+ * Returns handle on success, 0 on error.
+ */
+static acpi_handle ide_acpi_hwif_get_handle(ide_hwif_t *hwif)
+{
+ struct device *dev = hwif->gendev.parent;
+ acpi_handle dev_handle;
+ acpi_integer pcidevfn;
+ acpi_handle chan_handle;
+ int err;
+
+ DEBPRINT("ENTER: device %s\n", hwif->name);
+
+ if (!dev) {
+ DEBPRINT("no PCI device for %s\n", hwif->name);
+ return NULL;
+ }
+
+ err = ide_get_dev_handle(dev, &dev_handle, &pcidevfn);
+ if (err < 0) {
+ DEBPRINT("ide_get_dev_handle failed (%d)\n", err);
+ return NULL;
+ }
+
+ /* get child objects of dev_handle == channel objects,
+ * + _their_ children == drive objects */
+ /* channel is hwif->channel */
+ chan_handle = acpi_get_child(dev_handle, hwif->channel);
+ DEBPRINT("chan adr=%d: handle=0x%p\n",
+ hwif->channel, chan_handle);
+
+ return chan_handle;
+}
+
+/**
+ * ide_acpi_drive_get_handle - Get ACPI object handle for a given drive
+ * @drive: device to locate
+ *
+ * Retrieves the object handle of a given drive. According to the ACPI
+ * spec the drive is a child of the hwif.
+ *
+ * Returns handle on success, 0 on error.
+ */
+static acpi_handle ide_acpi_drive_get_handle(ide_drive_t *drive)
+{
+ ide_hwif_t *hwif = HWIF(drive);
+ int port;
+ acpi_handle drive_handle;
+
+ if (!hwif->acpidata)
+ return NULL;
+
+ if (!hwif->acpidata->obj_handle)
+ return NULL;
+
+ port = hwif->channel ? drive->dn - 2: drive->dn;
+
+ DEBPRINT("ENTER: %s at channel#: %d port#: %d\n",
+ drive->name, hwif->channel, port);
+
+
+ /* TBD: could also check ACPI object VALID bits */
+ drive_handle = acpi_get_child(hwif->acpidata->obj_handle, port);
+ DEBPRINT("drive %s handle 0x%p\n", drive->name, drive_handle);
+
+ return drive_handle;
+}
+
+/**
+ * do_drive_get_GTF - get the drive bootup default taskfile settings
+ * @drive: the drive for which the taskfile settings should be retrieved
+ * @gtf_length: number of bytes of _GTF data returned at @gtf_address
+ * @gtf_address: buffer containing _GTF taskfile arrays
+ *
+ * The _GTF method has no input parameters.
+ * It returns a variable number of register set values (registers
+ * hex 1F1..1F7, taskfiles).
+ * The <variable number> is not known in advance, so have ACPI-CA
+ * allocate the buffer as needed and return it, then free it later.
+ *
+ * The returned @gtf_length and @gtf_address are only valid if the
+ * function return value is 0.
+ */
+static int do_drive_get_GTF(ide_drive_t *drive,
+ unsigned int *gtf_length, unsigned long *gtf_address,
+ unsigned long *obj_loc)
+{
+ acpi_status status;
+ struct acpi_buffer output;
+ union acpi_object *out_obj;
+ ide_hwif_t *hwif = HWIF(drive);
+ struct device *dev = hwif->gendev.parent;
+ int err = -ENODEV;
+ int port;
+
+ *gtf_length = 0;
+ *gtf_address = 0UL;
+ *obj_loc = 0UL;
+
+ if (ide_noacpi)
+ return 0;
+
+ if (!dev) {
+ DEBPRINT("no PCI device for %s\n", hwif->name);
+ goto out;
+ }
+
+ if (!hwif->acpidata) {
+ DEBPRINT("no ACPI data for %s\n", hwif->name);
+ goto out;
+ }
+
+ port = hwif->channel ? drive->dn - 2: drive->dn;
+
+ if (!drive->acpidata) {
+ if (port == 0) {
+ drive->acpidata = &hwif->acpidata->master;
+ hwif->acpidata->master.drive = drive;
+ } else {
+ drive->acpidata = &hwif->acpidata->slave;
+ hwif->acpidata->slave.drive = drive;
+ }
+ }
+
+ DEBPRINT("ENTER: %s at %s, port#: %d, hard_port#: %d\n",
+ hwif->name, dev->bus_id, port, hwif->channel);
+
+ if (!drive->present) {
+ DEBPRINT("%s drive %d:%d not present\n",
+ hwif->name, hwif->channel, port);
+ goto out;
+ }
+
+ /* Get this drive's _ADR info. if not already known. */
+ if (!drive->acpidata->obj_handle) {
+ drive->acpidata->obj_handle = ide_acpi_drive_get_handle(drive);
+ if (!drive->acpidata->obj_handle) {
+ DEBPRINT("No ACPI object found for %s\n",
+ drive->name);
+ goto out;
+ }
+ }
+
+ /* Setting up output buffer */
+ output.length = ACPI_ALLOCATE_BUFFER;
+ output.pointer = NULL; /* ACPI-CA sets this; save/free it later */
+
+ /* _GTF has no input parameters */
+ err = -EIO;
+ status = acpi_evaluate_object(drive->acpidata->obj_handle, "_GTF",
+ NULL, &output);
+ if (ACPI_FAILURE(status)) {
+ printk(KERN_DEBUG
+ "%s: Run _GTF error: status = 0x%x\n",
+ __FUNCTION__, status);
+ goto out;
+ }
+
+ if (!output.length || !output.pointer) {
+ DEBPRINT("Run _GTF: "
+ "length or ptr is NULL (0x%llx, 0x%p)\n",
+ (unsigned long long)output.length,
+ output.pointer);
+ goto out;
+ }
+
+ out_obj = output.pointer;
+ if (out_obj->type != ACPI_TYPE_BUFFER) {
+ DEBPRINT("Run _GTF: error: "
+ "expected object type of ACPI_TYPE_BUFFER, "
+ "got 0x%x\n", out_obj->type);
+ err = -ENOENT;
+ kfree(output.pointer);
+ goto out;
+ }
+
+ if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
+ out_obj->buffer.length % REGS_PER_GTF) {
+ printk(KERN_ERR
+ "%s: unexpected GTF length (%d) or addr (0x%p)\n",
+ __FUNCTION__, out_obj->buffer.length,
+ out_obj->buffer.pointer);
+ err = -ENOENT;
+ kfree(output.pointer);
+ goto out;
+ }
+
+ *gtf_length = out_obj->buffer.length;
+ *gtf_address = (unsigned long)out_obj->buffer.pointer;
+ *obj_loc = (unsigned long)out_obj;
+ DEBPRINT("returning gtf_length=%d, gtf_address=0x%lx, obj_loc=0x%lx\n",
+ *gtf_length, *gtf_address, *obj_loc);
+ err = 0;
+out:
+ return err;
+}
+
+/**
+ * taskfile_load_raw - send taskfile registers to drive
+ * @drive: drive to which output is sent
+ * @gtf: raw ATA taskfile register set (0x1f1 - 0x1f7)
+ *
+ * Outputs IDE taskfile to the drive.
+ */
+static int taskfile_load_raw(ide_drive_t *drive,
+ const struct taskfile_array *gtf)
+{
+ ide_task_t args;
+ int err = 0;
+
+ DEBPRINT("(0x1f1-1f7): hex: "
+ "%02x %02x %02x %02x %02x %02x %02x\n",
+ gtf->tfa[0], gtf->tfa[1], gtf->tfa[2],
+ gtf->tfa[3], gtf->tfa[4], gtf->tfa[5], gtf->tfa[6]);
+
+ memset(&args, 0, sizeof(ide_task_t));
+ args.command_type = IDE_DRIVE_TASK_NO_DATA;
+ args.data_phase = TASKFILE_IN;
+ args.handler = &task_no_data_intr;
+
+ /* convert gtf to IDE Taskfile */
+ args.tfRegister[1] = gtf->tfa[0]; /* 0x1f1 */
+ args.tfRegister[2] = gtf->tfa[1]; /* 0x1f2 */
+ args.tfRegister[3] = gtf->tfa[2]; /* 0x1f3 */
+ args.tfRegister[4] = gtf->tfa[3]; /* 0x1f4 */
+ args.tfRegister[5] = gtf->tfa[4]; /* 0x1f5 */
+ args.tfRegister[6] = gtf->tfa[5]; /* 0x1f6 */
+ args.tfRegister[7] = gtf->tfa[6]; /* 0x1f7 */
+
+ if (ide_noacpitfs) {
+ DEBPRINT("_GTF execution disabled\n");
+ return err;
+ }
+
+ err = ide_raw_taskfile(drive, &args, NULL);
+ if (err)
+ printk(KERN_ERR "%s: ide_raw_taskfile failed: %u\n",
+ __FUNCTION__, err);
+
+ return err;
+}
+
+/**
+ * do_drive_set_taskfiles - write the drive taskfile settings from _GTF
+ * @drive: the drive to which the taskfile command should be sent
+ * @gtf_length: total number of bytes of _GTF taskfiles
+ * @gtf_address: location of _GTF taskfile arrays
+ *
+ * Write {gtf_address, length gtf_length} in groups of
+ * REGS_PER_GTF bytes.
+ */
+static int do_drive_set_taskfiles(ide_drive_t *drive,
+ unsigned int gtf_length,
+ unsigned long gtf_address)
+{
+ int rc = -ENODEV, err;
+ int gtf_count = gtf_length / REGS_PER_GTF;
+ int ix;
+ struct taskfile_array *gtf;
+
+ if (ide_noacpi)
+ return 0;
+
+ DEBPRINT("ENTER: %s, hard_port#: %d\n", drive->name, drive->dn);
+
+ if (!drive->present)
+ goto out;
+ if (!gtf_count) /* shouldn't be here */
+ goto out;
+
+ DEBPRINT("total GTF bytes=%u (0x%x), gtf_count=%d, addr=0x%lx\n",
+ gtf_length, gtf_length, gtf_count, gtf_address);
+
+ if (gtf_length % REGS_PER_GTF) {
+ printk(KERN_ERR "%s: unexpected GTF length (%d)\n",
+ __FUNCTION__, gtf_length);
+ goto out;
+ }
+
+ rc = 0;
+ for (ix = 0; ix < gtf_count; ix++) {
+ gtf = (struct taskfile_array *)
+ (gtf_address + ix * REGS_PER_GTF);
+
+ /* send all TaskFile registers (0x1f1-0x1f7) *in*that*order* */
+ err = taskfile_load_raw(drive, gtf);
+ if (err)
+ rc = err;
+ }
+
+out:
+ return rc;
+}
+
+/**
+ * ide_acpi_exec_tfs - get then write drive taskfile settings
+ * @drive: the drive for which the taskfile settings should be
+ * written.
+ *
+ * According to the ACPI spec this should be called after _STM
+ * has been evaluated for the interface. Some ACPI vendors interpret
+ * that as a hard requirement and modify the taskfile according
+ * to the Identify Drive information passed down with _STM.
+ * So one should really make sure to call this only after _STM has
+ * been executed.
+ */
+int ide_acpi_exec_tfs(ide_drive_t *drive)
+{
+ int ret;
+ unsigned int gtf_length;
+ unsigned long gtf_address;
+ unsigned long obj_loc;
+
+ if (ide_noacpi)
+ return 0;
+
+ DEBPRINT("call get_GTF, drive=%s port=%d\n", drive->name, drive->dn);
+
+ ret = do_drive_get_GTF(drive, >f_length, >f_address, &obj_loc);
+ if (ret < 0) {
+ DEBPRINT("get_GTF error (%d)\n", ret);
+ return ret;
+ }
+
+ DEBPRINT("call set_taskfiles, drive=%s\n", drive->name);
+
+ ret = do_drive_set_taskfiles(drive, gtf_length, gtf_address);
+ kfree((void *)obj_loc);
+ if (ret < 0) {
+ DEBPRINT("set_taskfiles error (%d)\n", ret);
+ }
+
+ DEBPRINT("ret=%d\n", ret);
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(ide_acpi_exec_tfs);
+
+/**
+ * ide_acpi_get_timing - get the channel (controller) timings
+ * @hwif: target IDE interface (channel)
+ *
+ * This function executes the _GTM ACPI method for the target channel.
+ *
+ */
+void ide_acpi_get_timing(ide_hwif_t *hwif)
+{
+ acpi_status status;
+ struct acpi_buffer output;
+ union acpi_object *out_obj;
+
+ if (ide_noacpi)
+ return;
+
+ DEBPRINT("ENTER:\n");
+
+ if (!hwif->acpidata) {
+ DEBPRINT("no ACPI data for %s\n", hwif->name);
+ return;
+ }
+
+ /* Setting up output buffer for _GTM */
+ output.length = ACPI_ALLOCATE_BUFFER;
+ output.pointer = NULL; /* ACPI-CA sets this; save/free it later */
+
+ /* _GTM has no input parameters */
+ status = acpi_evaluate_object(hwif->acpidata->obj_handle, "_GTM",
+ NULL, &output);
+
+ DEBPRINT("_GTM status: %d, outptr: 0x%p, outlen: 0x%llx\n",
+ status, output.pointer,
+ (unsigned long long)output.length);
+
+ if (ACPI_FAILURE(status)) {
+ DEBPRINT("Run _GTM error: status = 0x%x\n", status);
+ return;
+ }
+
+ if (!output.length || !output.pointer) {
+ DEBPRINT("Run _GTM: length or ptr is NULL (0x%llx, 0x%p)\n",
+ (unsigned long long)output.length,
+ output.pointer);
+ kfree(output.pointer);
+ return;
+ }
+
+ out_obj = output.pointer;
+ if (out_obj->type != ACPI_TYPE_BUFFER) {
+ kfree(output.pointer);
+ DEBPRINT("Run _GTM: error: "
+ "expected object type of ACPI_TYPE_BUFFER, "
+ "got 0x%x\n", out_obj->type);
+ return;
+ }
+
+ if (!out_obj->buffer.length || !out_obj->buffer.pointer ||
+ out_obj->buffer.length != sizeof(struct GTM_buffer)) {
+ kfree(output.pointer);
+ printk(KERN_ERR
+ "%s: unexpected _GTM length (0x%x)[should be 0x%x] or addr (0x%p)\n",
+ __FUNCTION__, out_obj->buffer.length,
+ sizeof(struct GTM_buffer), out_obj->buffer.pointer);
+ return;
+ }
+
+ memcpy(&hwif->acpidata->gtm, out_obj->buffer.pointer,
+ sizeof(struct GTM_buffer));
+
+ DEBPRINT("_GTM info: ptr: 0x%p, len: 0x%x, exp.len: 0x%Zx\n",
+ out_obj->buffer.pointer, out_obj->buffer.length,
+ sizeof(struct GTM_buffer));
+
+ DEBPRINT("_GTM fields: 0x%x, 0x%x, 0x%x, 0x%x, 0x%x\n",
+ hwif->acpidata->gtm.PIO_speed0,
+ hwif->acpidata->gtm.DMA_speed0,
+ hwif->acpidata->gtm.PIO_speed1,
+ hwif->acpidata->gtm.DMA_speed1,
+ hwif->acpidata->gtm.GTM_flags);
+
+ kfree(output.pointer);
+}
+EXPORT_SYMBOL_GPL(ide_acpi_get_timing);
+
+/**
+ * ide_acpi_push_timing - set the channel (controller) timings
+ * @hwif: target IDE interface (channel)
+ *
+ * This function executes the _STM ACPI method for the target channel.
+ *
+ * _STM requires Identify Drive data, which has to passed as an argument.
+ * Unfortunately hd_driveid is a mangled version which we can't readily
+ * use; hence we'll get the information afresh.
+ */
+void ide_acpi_push_timing(ide_hwif_t *hwif)
+{
+ acpi_status status;
+ struct acpi_object_list input;
+ union acpi_object in_params[3];
+ struct ide_acpi_drive_link *master = &hwif->acpidata->master;
+ struct ide_acpi_drive_link *slave = &hwif->acpidata->slave;
+
+ if (ide_noacpi)
+ return;
+
+ DEBPRINT("ENTER:\n");
+
+ if (!hwif->acpidata) {
+ DEBPRINT("no ACPI data for %s\n", hwif->name);
+ return;
+ }
+
+ /* Give the GTM buffer + drive Identify data to the channel via the
+ * _STM method: */
+ /* setup input parameters buffer for _STM */
+ input.count = 3;
+ input.pointer = in_params;
+ in_params[0].type = ACPI_TYPE_BUFFER;
+ in_params[0].buffer.length = sizeof(struct GTM_buffer);
+ in_params[0].buffer.pointer = (u8 *)&hwif->acpidata->gtm;
+ in_params[1].type = ACPI_TYPE_BUFFER;
+ in_params[1].buffer.length = sizeof(struct hd_driveid);
+ in_params[1].buffer.pointer = (u8 *)&master->idbuff;
+ in_params[2].type = ACPI_TYPE_BUFFER;
+ in_params[2].buffer.length = sizeof(struct hd_driveid);
+ in_params[2].buffer.pointer = (u8 *)&slave->idbuff;
+ /* Output buffer: _STM has no output */
+
+ status = acpi_evaluate_object(hwif->acpidata->obj_handle, "_STM",
+ &input, NULL);
+
+ if (ACPI_FAILURE(status)) {
+ DEBPRINT("Run _STM error: status = 0x%x\n", status);
+ }
+ DEBPRINT("_STM status: %d\n", status);
+}
+EXPORT_SYMBOL_GPL(ide_acpi_push_timing);
+
+/**
+ * ide_acpi_init - initialize the ACPI link for an IDE interface
+ * @hwif: target IDE interface (channel)
+ *
+ * The ACPI spec is not quite clear when the drive identify buffer
+ * should be obtained. Calling IDENTIFY DEVICE during shutdown
+ * is not the best of ideas as the drive might already being put to
+ * sleep. And obviously we can't call it during resume.
+ * So we get the information during startup; but this means that
+ * any changes during run-time will be lost after resume.
+ */
+void ide_acpi_init(ide_hwif_t *hwif)
+{
+ int unit;
+ int err;
+ struct ide_acpi_drive_link *master;
+ struct ide_acpi_drive_link *slave;
+
+ hwif->acpidata = kzalloc(sizeof(struct ide_acpi_hwif_link), GFP_KERNEL);
+ if (!hwif->acpidata)
+ return;
+
+ hwif->acpidata->obj_handle = ide_acpi_hwif_get_handle(hwif);
+ if (!hwif->acpidata->obj_handle) {
+ DEBPRINT("no ACPI object for %s found\n", hwif->name);
+ kfree(hwif->acpidata);
+ hwif->acpidata = NULL;
+ return;
+ }
+
+ /*
+ * The ACPI spec mandates that we send information
+ * for both drives, regardless whether they are connected
+ * or not.
+ */
+ hwif->acpidata->master.drive = &hwif->drives[0];
+ hwif->drives[0].acpidata = &hwif->acpidata->master;
+ master = &hwif->acpidata->master;
+
+ hwif->acpidata->slave.drive = &hwif->drives[1];
+ hwif->drives[1].acpidata = &hwif->acpidata->slave;
+ slave = &hwif->acpidata->slave;
+
+
+ /*
+ * Send IDENTIFY for each drive
+ */
+ if (master->drive->present) {
+ err = taskfile_lib_get_identify(master->drive, master->idbuff);
+ if (err) {
+ DEBPRINT("identify device %s failed (%d)\n",
+ master->drive->name, err);
+ }
+ }
+
+ if (slave->drive->present) {
+ err = taskfile_lib_get_identify(slave->drive, slave->idbuff);
+ if (err) {
+ DEBPRINT("identify device %s failed (%d)\n",
+ slave->drive->name, err);
+ }
+ }
+
+ if (ide_noacpionboot) {
+ DEBPRINT("ACPI methods disabled on boot\n");
+ return;
+ }
+
+ /*
+ * ACPI requires us to call _STM on startup
+ */
+ ide_acpi_get_timing(hwif);
+ ide_acpi_push_timing(hwif);
+
+ for (unit = 0; unit < MAX_DRIVES; ++unit) {
+ ide_drive_t *drive = &hwif->drives[unit];
+
+ if (drive->present) {
+ /* Execute ACPI startup code */
+ ide_acpi_exec_tfs(drive);
+ }
+ }
+}
+EXPORT_SYMBOL_GPL(ide_acpi_init);