1 files changed, 295 insertions, 0 deletions
diff --git a/drivers/ata/libata-zpodd.c b/drivers/ata/libata-zpodd.c
new file mode 100644
index 0000000000..eefda51f97
--- /dev/null
+++ b/drivers/ata/libata-zpodd.c
@@ -0,0 +1,295 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/libata.h>
+#include <linux/cdrom.h>
+#include <linux/pm_runtime.h>
+#include <linux/module.h>
+#include <linux/pm_qos.h>
+#include <scsi/scsi_device.h>
+
+#include "libata.h"
+
+static int zpodd_poweroff_delay = 30; /* 30 seconds for power off delay */
+module_param(zpodd_poweroff_delay, int, 0644);
+MODULE_PARM_DESC(zpodd_poweroff_delay, "Poweroff delay for ZPODD in seconds");
+
+enum odd_mech_type {
+	ODD_MECH_TYPE_SLOT,
+	ODD_MECH_TYPE_DRAWER,
+	ODD_MECH_TYPE_UNSUPPORTED,
+};
+
+struct zpodd {
+	enum odd_mech_type	mech_type; /* init during probe, RO afterwards */
+	struct ata_device	*dev;
+
+	/* The following fields are synchronized by PM core. */
+	bool			from_notify; /* resumed as a result of
+					      * acpi wake notification */
+	bool			zp_ready; /* ZP ready state */
+	unsigned long		last_ready; /* last ZP ready timestamp */
+	bool			zp_sampled; /* ZP ready state sampled */
+	bool			powered_off; /* ODD is powered off
+					      *	during suspend */
+};
+
+static int eject_tray(struct ata_device *dev)
+{
+	struct ata_taskfile tf;
+	static const char cdb[ATAPI_CDB_LEN] = {  GPCMD_START_STOP_UNIT,
+		0, 0, 0,
+		0x02,     /* LoEj */
+		0, 0, 0, 0, 0, 0, 0,
+	};
+
+	ata_tf_init(dev, &tf);
+	tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
+	tf.command = ATA_CMD_PACKET;
+	tf.protocol = ATAPI_PROT_NODATA;
+
+	return ata_exec_internal(dev, &tf, cdb, DMA_NONE, NULL, 0, 0);
+}
+
+/* Per the spec, only slot type and drawer type ODD can be supported */
+static enum odd_mech_type zpodd_get_mech_type(struct ata_device *dev)
+{
+	char *buf;
+	unsigned int ret;
+	struct rm_feature_desc *desc;
+	struct ata_taskfile tf;
+	static const char cdb[ATAPI_CDB_LEN] = {  GPCMD_GET_CONFIGURATION,
+			2,      /* only 1 feature descriptor requested */
+			0, 3,   /* 3, removable medium feature */
+			0, 0, 0,/* reserved */
+			0, 16,
+			0, 0, 0,
+	};
+
+	buf = kzalloc(16, GFP_KERNEL);
+	if (!buf)
+		return ODD_MECH_TYPE_UNSUPPORTED;
+	desc = (void *)(buf + 8);
+
+	ata_tf_init(dev, &tf);
+	tf.flags = ATA_TFLAG_ISADDR | ATA_TFLAG_DEVICE;
+	tf.command = ATA_CMD_PACKET;
+	tf.protocol = ATAPI_PROT_PIO;
+	tf.lbam = 16;
+
+	ret = ata_exec_internal(dev, &tf, cdb, DMA_FROM_DEVICE,
+				buf, 16, 0);
+	if (ret) {
+		kfree(buf);
+		return ODD_MECH_TYPE_UNSUPPORTED;
+	}
+
+	if (be16_to_cpu(desc->feature_code) != 3) {
+		kfree(buf);
+		return ODD_MECH_TYPE_UNSUPPORTED;
+	}
+
+	if (desc->mech_type == 0 && desc->load == 0 && desc->eject == 1) {
+		kfree(buf);
+		return ODD_MECH_TYPE_SLOT;
+	} else if (desc->mech_type == 1 && desc->load == 0 &&
+		   desc->eject == 1) {
+		kfree(buf);
+		return ODD_MECH_TYPE_DRAWER;
+	} else {
+		kfree(buf);
+		return ODD_MECH_TYPE_UNSUPPORTED;
+	}
+}
+
+/* Test if ODD is zero power ready by sense code */
+static bool zpready(struct ata_device *dev)
+{
+	u8 sense_key, *sense_buf;
+	unsigned int ret, asc, ascq, add_len;
+	struct zpodd *zpodd = dev->zpodd;
+
+	ret = atapi_eh_tur(dev, &sense_key);
+
+	if (!ret || sense_key != NOT_READY)
+		return false;
+
+	sense_buf = dev->link->ap->sector_buf;
+	ret = atapi_eh_request_sense(dev, sense_buf, sense_key);
+	if (ret)
+		return false;
+
+	/* sense valid */
+	if ((sense_buf[0] & 0x7f) != 0x70)
+		return false;
+
+	add_len = sense_buf[7];
+	/* has asc and ascq */
+	if (add_len < 6)
+		return false;
+
+	asc = sense_buf[12];
+	ascq = sense_buf[13];
+
+	if (zpodd->mech_type == ODD_MECH_TYPE_SLOT)
+		/* no media inside */
+		return asc == 0x3a;
+	else
+		/* no media inside and door closed */
+		return asc == 0x3a && ascq == 0x01;
+}
+
+/*
+ * Update the zpodd->zp_ready field. This field will only be set
+ * if the ODD has stayed in ZP ready state for zpodd_poweroff_delay
+ * time, and will be used to decide if power off is allowed. If it
+ * is set, it will be cleared during resume from powered off state.
+ */
+void zpodd_on_suspend(struct ata_device *dev)
+{
+	struct zpodd *zpodd = dev->zpodd;
+	unsigned long expires;
+
+	if (!zpready(dev)) {
+		zpodd->zp_sampled = false;
+		zpodd->zp_ready = false;
+		return;
+	}
+
+	if (!zpodd->zp_sampled) {
+		zpodd->zp_sampled = true;
+		zpodd->last_ready = jiffies;
+		return;
+	}
+
+	expires = zpodd->last_ready +
+		  msecs_to_jiffies(zpodd_poweroff_delay * 1000);
+	if (time_before(jiffies, expires))
+		return;
+
+	zpodd->zp_ready = true;
+}
+
+bool zpodd_zpready(struct ata_device *dev)
+{
+	struct zpodd *zpodd = dev->zpodd;
+	return zpodd->zp_ready;
+}
+
+/*
+ * Enable runtime wake capability through ACPI and set the powered_off flag,
+ * this flag will be used during resume to decide what operations are needed
+ * to take.
+ *
+ * Also, media poll needs to be silenced, so that it doesn't bring the ODD
+ * back to full power state every few seconds.
+ */
+void zpodd_enable_run_wake(struct ata_device *dev)
+{
+	struct zpodd *zpodd = dev->zpodd;
+
+	sdev_disable_disk_events(dev->sdev);
+
+	zpodd->powered_off = true;
+	acpi_pm_set_device_wakeup(&dev->tdev, true);
+}
+
+/* Disable runtime wake capability if it is enabled */
+void zpodd_disable_run_wake(struct ata_device *dev)
+{
+	struct zpodd *zpodd = dev->zpodd;
+
+	if (zpodd->powered_off)
+		acpi_pm_set_device_wakeup(&dev->tdev, false);
+}
+
+/*
+ * Post power on processing after the ODD has been recovered. If the
+ * ODD wasn't powered off during suspend, it doesn't do anything.
+ *
+ * For drawer type ODD, if it is powered on due to user pressed the
+ * eject button, the tray needs to be ejected. This can only be done
+ * after the ODD has been recovered, i.e. link is initialized and
+ * device is able to process NON_DATA PIO command, as eject needs to
+ * send command for the ODD to process.
+ *
+ * The from_notify flag set in wake notification handler function
+ * zpodd_wake_dev represents if power on is due to user's action.
+ *
+ * For both types of ODD, several fields need to be reset.
+ */
+void zpodd_post_poweron(struct ata_device *dev)
+{
+	struct zpodd *zpodd = dev->zpodd;
+
+	if (!zpodd->powered_off)
+		return;
+
+	zpodd->powered_off = false;
+
+	if (zpodd->from_notify) {
+		zpodd->from_notify = false;
+		if (zpodd->mech_type == ODD_MECH_TYPE_DRAWER)
+			eject_tray(dev);
+	}
+
+	zpodd->zp_sampled = false;
+	zpodd->zp_ready = false;
+
+	sdev_enable_disk_events(dev->sdev);
+}
+
+static void zpodd_wake_dev(acpi_handle handle, u32 event, void *context)
+{
+	struct ata_device *ata_dev = context;
+	struct zpodd *zpodd = ata_dev->zpodd;
+	struct device *dev = &ata_dev->sdev->sdev_gendev;
+
+	if (event == ACPI_NOTIFY_DEVICE_WAKE && pm_runtime_suspended(dev)) {
+		zpodd->from_notify = true;
+		pm_runtime_resume(dev);
+	}
+}
+
+static void ata_acpi_add_pm_notifier(struct ata_device *dev)
+{
+	acpi_handle handle = ata_dev_acpi_handle(dev);
+	acpi_install_notify_handler(handle, ACPI_SYSTEM_NOTIFY,
+				    zpodd_wake_dev, dev);
+}
+
+static void ata_acpi_remove_pm_notifier(struct ata_device *dev)
+{
+	acpi_handle handle = ata_dev_acpi_handle(dev);
+	acpi_remove_notify_handler(handle, ACPI_SYSTEM_NOTIFY, zpodd_wake_dev);
+}
+
+void zpodd_init(struct ata_device *dev)
+{
+	struct acpi_device *adev = ACPI_COMPANION(&dev->tdev);
+	enum odd_mech_type mech_type;
+	struct zpodd *zpodd;
+
+	if (dev->zpodd || !adev || !acpi_device_can_poweroff(adev))
+		return;
+
+	mech_type = zpodd_get_mech_type(dev);
+	if (mech_type == ODD_MECH_TYPE_UNSUPPORTED)
+		return;
+
+	zpodd = kzalloc(sizeof(struct zpodd), GFP_KERNEL);
+	if (!zpodd)
+		return;
+
+	zpodd->mech_type = mech_type;
+
+	ata_acpi_add_pm_notifier(dev);
+	zpodd->dev = dev;
+	dev->zpodd = zpodd;
+	dev_pm_qos_expose_flags(&dev->tdev, 0);
+}
+
+void zpodd_exit(struct ata_device *dev)
+{
+	ata_acpi_remove_pm_notifier(dev);
+	kfree(dev->zpodd);
+	dev->zpodd = NULL;
+}