1 files changed, 281 insertions, 0 deletions
diff --git a/drivers/ide/ide-pm.c b/drivers/ide/ide-pm.c
new file mode 100644
index 000000000..59217aa1d
--- /dev/null
+++ b/drivers/ide/ide-pm.c
@@ -0,0 +1,281 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kernel.h>
+#include <linux/gfp.h>
+#include <linux/ide.h>
+
+int generic_ide_suspend(struct device *dev, pm_message_t mesg)
+{
+	ide_drive_t *drive = to_ide_device(dev);
+	ide_drive_t *pair = ide_get_pair_dev(drive);
+	ide_hwif_t *hwif = drive->hwif;
+	struct request *rq;
+	struct ide_pm_state rqpm;
+	int ret;
+
+	if (ide_port_acpi(hwif)) {
+		/* call ACPI _GTM only once */
+		if ((drive->dn & 1) == 0 || pair == NULL)
+			ide_acpi_get_timing(hwif);
+	}
+
+	memset(&rqpm, 0, sizeof(rqpm));
+	rq = blk_get_request(drive->queue, REQ_OP_DRV_IN, 0);
+	ide_req(rq)->type = ATA_PRIV_PM_SUSPEND;
+	rq->special = &rqpm;
+	rqpm.pm_step = IDE_PM_START_SUSPEND;
+	if (mesg.event == PM_EVENT_PRETHAW)
+		mesg.event = PM_EVENT_FREEZE;
+	rqpm.pm_state = mesg.event;
+
+	blk_execute_rq(drive->queue, NULL, rq, 0);
+	ret = scsi_req(rq)->result ? -EIO : 0;
+	blk_put_request(rq);
+
+	if (ret == 0 && ide_port_acpi(hwif)) {
+		/* call ACPI _PS3 only after both devices are suspended */
+		if ((drive->dn & 1) || pair == NULL)
+			ide_acpi_set_state(hwif, 0);
+	}
+
+	return ret;
+}
+
+static void ide_end_sync_rq(struct request *rq, blk_status_t error)
+{
+	complete(rq->end_io_data);
+}
+
+static int ide_pm_execute_rq(struct request *rq)
+{
+	struct request_queue *q = rq->q;
+	DECLARE_COMPLETION_ONSTACK(wait);
+
+	rq->end_io_data = &wait;
+	rq->end_io = ide_end_sync_rq;
+
+	spin_lock_irq(q->queue_lock);
+	if (unlikely(blk_queue_dying(q))) {
+		rq->rq_flags |= RQF_QUIET;
+		scsi_req(rq)->result = -ENXIO;
+		__blk_end_request_all(rq, BLK_STS_OK);
+		spin_unlock_irq(q->queue_lock);
+		return -ENXIO;
+	}
+	__elv_add_request(q, rq, ELEVATOR_INSERT_FRONT);
+	__blk_run_queue_uncond(q);
+	spin_unlock_irq(q->queue_lock);
+
+	wait_for_completion_io(&wait);
+
+	return scsi_req(rq)->result ? -EIO : 0;
+}
+
+int generic_ide_resume(struct device *dev)
+{
+	ide_drive_t *drive = to_ide_device(dev);
+	ide_drive_t *pair = ide_get_pair_dev(drive);
+	ide_hwif_t *hwif = drive->hwif;
+	struct request *rq;
+	struct ide_pm_state rqpm;
+	int err;
+
+	if (ide_port_acpi(hwif)) {
+		/* call ACPI _PS0 / _STM only once */
+		if ((drive->dn & 1) == 0 || pair == NULL) {
+			ide_acpi_set_state(hwif, 1);
+			ide_acpi_push_timing(hwif);
+		}
+
+		ide_acpi_exec_tfs(drive);
+	}
+
+	memset(&rqpm, 0, sizeof(rqpm));
+	rq = blk_get_request(drive->queue, REQ_OP_DRV_IN, BLK_MQ_REQ_PREEMPT);
+	ide_req(rq)->type = ATA_PRIV_PM_RESUME;
+	rq->special = &rqpm;
+	rqpm.pm_step = IDE_PM_START_RESUME;
+	rqpm.pm_state = PM_EVENT_ON;
+
+	err = ide_pm_execute_rq(rq);
+	blk_put_request(rq);
+
+	if (err == 0 && dev->driver) {
+		struct ide_driver *drv = to_ide_driver(dev->driver);
+
+		if (drv->resume)
+			drv->resume(drive);
+	}
+
+	return err;
+}
+
+void ide_complete_power_step(ide_drive_t *drive, struct request *rq)
+{
+	struct ide_pm_state *pm = rq->special;
+
+#ifdef DEBUG_PM
+	printk(KERN_INFO "%s: complete_power_step(step: %d)\n",
+		drive->name, pm->pm_step);
+#endif
+	if (drive->media != ide_disk)
+		return;
+
+	switch (pm->pm_step) {
+	case IDE_PM_FLUSH_CACHE:	/* Suspend step 1 (flush cache) */
+		if (pm->pm_state == PM_EVENT_FREEZE)
+			pm->pm_step = IDE_PM_COMPLETED;
+		else
+			pm->pm_step = IDE_PM_STANDBY;
+		break;
+	case IDE_PM_STANDBY:		/* Suspend step 2 (standby) */
+		pm->pm_step = IDE_PM_COMPLETED;
+		break;
+	case IDE_PM_RESTORE_PIO:	/* Resume step 1 (restore PIO) */
+		pm->pm_step = IDE_PM_IDLE;
+		break;
+	case IDE_PM_IDLE:		/* Resume step 2 (idle)*/
+		pm->pm_step = IDE_PM_RESTORE_DMA;
+		break;
+	}
+}
+
+ide_startstop_t ide_start_power_step(ide_drive_t *drive, struct request *rq)
+{
+	struct ide_pm_state *pm = rq->special;
+	struct ide_cmd cmd = { };
+
+	switch (pm->pm_step) {
+	case IDE_PM_FLUSH_CACHE:	/* Suspend step 1 (flush cache) */
+		if (drive->media != ide_disk)
+			break;
+		/* Not supported? Switch to next step now. */
+		if (ata_id_flush_enabled(drive->id) == 0 ||
+		    (drive->dev_flags & IDE_DFLAG_WCACHE) == 0) {
+			ide_complete_power_step(drive, rq);
+			return ide_stopped;
+		}
+		if (ata_id_flush_ext_enabled(drive->id))
+			cmd.tf.command = ATA_CMD_FLUSH_EXT;
+		else
+			cmd.tf.command = ATA_CMD_FLUSH;
+		goto out_do_tf;
+	case IDE_PM_STANDBY:		/* Suspend step 2 (standby) */
+		cmd.tf.command = ATA_CMD_STANDBYNOW1;
+		goto out_do_tf;
+	case IDE_PM_RESTORE_PIO:	/* Resume step 1 (restore PIO) */
+		ide_set_max_pio(drive);
+		/*
+		 * skip IDE_PM_IDLE for ATAPI devices
+		 */
+		if (drive->media != ide_disk)
+			pm->pm_step = IDE_PM_RESTORE_DMA;
+		else
+			ide_complete_power_step(drive, rq);
+		return ide_stopped;
+	case IDE_PM_IDLE:		/* Resume step 2 (idle) */
+		cmd.tf.command = ATA_CMD_IDLEIMMEDIATE;
+		goto out_do_tf;
+	case IDE_PM_RESTORE_DMA:	/* Resume step 3 (restore DMA) */
+		/*
+		 * Right now, all we do is call ide_set_dma(drive),
+		 * we could be smarter and check for current xfer_speed
+		 * in struct drive etc...
+		 */
+		if (drive->hwif->dma_ops == NULL)
+			break;
+		/*
+		 * TODO: respect IDE_DFLAG_USING_DMA
+		 */
+		ide_set_dma(drive);
+		break;
+	}
+
+	pm->pm_step = IDE_PM_COMPLETED;
+
+	return ide_stopped;
+
+out_do_tf:
+	cmd.valid.out.tf = IDE_VALID_OUT_TF | IDE_VALID_DEVICE;
+	cmd.valid.in.tf  = IDE_VALID_IN_TF  | IDE_VALID_DEVICE;
+	cmd.protocol = ATA_PROT_NODATA;
+
+	return do_rw_taskfile(drive, &cmd);
+}
+
+/**
+ *	ide_complete_pm_rq - end the current Power Management request
+ *	@drive: target drive
+ *	@rq: request
+ *
+ *	This function cleans up the current PM request and stops the queue
+ *	if necessary.
+ */
+void ide_complete_pm_rq(ide_drive_t *drive, struct request *rq)
+{
+	struct request_queue *q = drive->queue;
+	struct ide_pm_state *pm = rq->special;
+	unsigned long flags;
+
+	ide_complete_power_step(drive, rq);
+	if (pm->pm_step != IDE_PM_COMPLETED)
+		return;
+
+#ifdef DEBUG_PM
+	printk("%s: completing PM request, %s\n", drive->name,
+	       (ide_req(rq)->type == ATA_PRIV_PM_SUSPEND) ? "suspend" : "resume");
+#endif
+	spin_lock_irqsave(q->queue_lock, flags);
+	if (ide_req(rq)->type == ATA_PRIV_PM_SUSPEND)
+		blk_stop_queue(q);
+	else
+		drive->dev_flags &= ~IDE_DFLAG_BLOCKED;
+	spin_unlock_irqrestore(q->queue_lock, flags);
+
+	drive->hwif->rq = NULL;
+
+	if (blk_end_request(rq, BLK_STS_OK, 0))
+		BUG();
+}
+
+void ide_check_pm_state(ide_drive_t *drive, struct request *rq)
+{
+	struct ide_pm_state *pm = rq->special;
+
+	if (blk_rq_is_private(rq) &&
+	    ide_req(rq)->type == ATA_PRIV_PM_SUSPEND &&
+	    pm->pm_step == IDE_PM_START_SUSPEND)
+		/* Mark drive blocked when starting the suspend sequence. */
+		drive->dev_flags |= IDE_DFLAG_BLOCKED;
+	else if (blk_rq_is_private(rq) &&
+	         ide_req(rq)->type == ATA_PRIV_PM_RESUME &&
+		 pm->pm_step == IDE_PM_START_RESUME) {
+		/*
+		 * The first thing we do on wakeup is to wait for BSY bit to
+		 * go away (with a looong timeout) as a drive on this hwif may
+		 * just be POSTing itself.
+		 * We do that before even selecting as the "other" device on
+		 * the bus may be broken enough to walk on our toes at this
+		 * point.
+		 */
+		ide_hwif_t *hwif = drive->hwif;
+		const struct ide_tp_ops *tp_ops = hwif->tp_ops;
+		struct request_queue *q = drive->queue;
+		unsigned long flags;
+		int rc;
+#ifdef DEBUG_PM
+		printk("%s: Wakeup request inited, waiting for !BSY...\n", drive->name);
+#endif
+		rc = ide_wait_not_busy(hwif, 35000);
+		if (rc)
+			printk(KERN_WARNING "%s: bus not ready on wakeup\n", drive->name);
+		tp_ops->dev_select(drive);
+		tp_ops->write_devctl(hwif, ATA_DEVCTL_OBS);
+		rc = ide_wait_not_busy(hwif, 100000);
+		if (rc)
+			printk(KERN_WARNING "%s: drive not ready on wakeup\n", drive->name);
+
+		spin_lock_irqsave(q->queue_lock, flags);
+		blk_start_queue(q);
+		spin_unlock_irqrestore(q->queue_lock, flags);
+	}
+}