1 files changed, 779 insertions, 0 deletions

diff --git a/drivers/soundwire/intel_auxdevice.c b/drivers/soundwire/intel_auxdevice.c
new file mode 100644
index 0000000000..93698532de
--- /dev/null
+++ b/drivers/soundwire/intel_auxdevice.c
@@ -0,0 +1,779 @@
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+// Copyright(c) 2015-22 Intel Corporation.
+
+/*
+ * Soundwire Intel Manager Driver
+ */
+
+#include <linux/acpi.h>
+#include <linux/debugfs.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/auxiliary_bus.h>
+#include <sound/pcm_params.h>
+#include <linux/pm_runtime.h>
+#include <sound/soc.h>
+#include <linux/soundwire/sdw_registers.h>
+#include <linux/soundwire/sdw.h>
+#include <linux/soundwire/sdw_intel.h>
+#include "cadence_master.h"
+#include "bus.h"
+#include "intel.h"
+#include "intel_auxdevice.h"
+
+#define INTEL_MASTER_SUSPEND_DELAY_MS	3000
+
+/*
+ * debug/config flags for the Intel SoundWire Master.
+ *
+ * Since we may have multiple masters active, we can have up to 8
+ * flags reused in each byte, with master0 using the ls-byte, etc.
+ */
+
+#define SDW_INTEL_MASTER_DISABLE_PM_RUNTIME		BIT(0)
+#define SDW_INTEL_MASTER_DISABLE_CLOCK_STOP		BIT(1)
+#define SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE	BIT(2)
+#define SDW_INTEL_MASTER_DISABLE_MULTI_LINK		BIT(3)
+
+static int md_flags;
+module_param_named(sdw_md_flags, md_flags, int, 0444);
+MODULE_PARM_DESC(sdw_md_flags, "SoundWire Intel Master device flags (0x0 all off)");
+
+struct wake_capable_part {
+	const u16 mfg_id;
+	const u16 part_id;
+};
+
+static struct wake_capable_part wake_capable_list[] = {
+	{0x025d, 0x5682},
+	{0x025d, 0x700},
+	{0x025d, 0x711},
+	{0x025d, 0x1712},
+	{0x025d, 0x1713},
+	{0x025d, 0x1716},
+	{0x025d, 0x1717},
+	{0x025d, 0x712},
+	{0x025d, 0x713},
+	{0x025d, 0x714},
+	{0x025d, 0x715},
+	{0x025d, 0x716},
+	{0x025d, 0x717},
+	{0x025d, 0x722},
+};
+
+static bool is_wake_capable(struct sdw_slave *slave)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(wake_capable_list); i++)
+		if (slave->id.part_id == wake_capable_list[i].part_id &&
+		    slave->id.mfg_id == wake_capable_list[i].mfg_id)
+			return true;
+	return false;
+}
+
+static int generic_pre_bank_switch(struct sdw_bus *bus)
+{
+	struct sdw_cdns *cdns = bus_to_cdns(bus);
+	struct sdw_intel *sdw = cdns_to_intel(cdns);
+
+	return sdw->link_res->hw_ops->pre_bank_switch(sdw);
+}
+
+static int generic_post_bank_switch(struct sdw_bus *bus)
+{
+	struct sdw_cdns *cdns = bus_to_cdns(bus);
+	struct sdw_intel *sdw = cdns_to_intel(cdns);
+
+	return sdw->link_res->hw_ops->post_bank_switch(sdw);
+}
+
+static void generic_new_peripheral_assigned(struct sdw_bus *bus,
+					    struct sdw_slave *slave,
+					    int dev_num)
+{
+	struct sdw_cdns *cdns = bus_to_cdns(bus);
+	struct sdw_intel *sdw = cdns_to_intel(cdns);
+	int dev_num_min;
+	int dev_num_max;
+	bool wake_capable = slave->prop.wake_capable || is_wake_capable(slave);
+
+	if (wake_capable) {
+		dev_num_min = SDW_INTEL_DEV_NUM_IDA_MIN;
+		dev_num_max = SDW_MAX_DEVICES;
+	} else {
+		dev_num_min = 1;
+		dev_num_max = SDW_INTEL_DEV_NUM_IDA_MIN - 1;
+	}
+
+	/* paranoia check, this should never happen */
+	if (dev_num < dev_num_min || dev_num > dev_num_max)  {
+		dev_err(bus->dev, "%s: invalid dev_num %d, wake supported %d\n",
+			__func__, dev_num, slave->prop.wake_capable);
+		return;
+	}
+
+	if (sdw->link_res->hw_ops->program_sdi && wake_capable)
+		sdw->link_res->hw_ops->program_sdi(sdw, dev_num);
+}
+
+static int sdw_master_read_intel_prop(struct sdw_bus *bus)
+{
+	struct sdw_master_prop *prop = &bus->prop;
+	struct fwnode_handle *link;
+	char name[32];
+	u32 quirk_mask;
+
+	/* Find master handle */
+	snprintf(name, sizeof(name),
+		 "mipi-sdw-link-%d-subproperties", bus->link_id);
+
+	link = device_get_named_child_node(bus->dev, name);
+	if (!link) {
+		dev_err(bus->dev, "Master node %s not found\n", name);
+		return -EIO;
+	}
+
+	fwnode_property_read_u32(link,
+				 "intel-sdw-ip-clock",
+				 &prop->mclk_freq);
+
+	/* the values reported by BIOS are the 2x clock, not the bus clock */
+	prop->mclk_freq /= 2;
+
+	fwnode_property_read_u32(link,
+				 "intel-quirk-mask",
+				 &quirk_mask);
+
+	if (quirk_mask & SDW_INTEL_QUIRK_MASK_BUS_DISABLE)
+		prop->hw_disabled = true;
+
+	prop->quirks = SDW_MASTER_QUIRKS_CLEAR_INITIAL_CLASH |
+		SDW_MASTER_QUIRKS_CLEAR_INITIAL_PARITY;
+
+	return 0;
+}
+
+static int intel_prop_read(struct sdw_bus *bus)
+{
+	/* Initialize with default handler to read all DisCo properties */
+	sdw_master_read_prop(bus);
+
+	/* read Intel-specific properties */
+	sdw_master_read_intel_prop(bus);
+
+	return 0;
+}
+
+static DEFINE_IDA(intel_peripheral_ida);
+
+static int intel_get_device_num_ida(struct sdw_bus *bus, struct sdw_slave *slave)
+{
+	int bit;
+
+	if (slave->prop.wake_capable || is_wake_capable(slave))
+		return ida_alloc_range(&intel_peripheral_ida,
+				       SDW_INTEL_DEV_NUM_IDA_MIN, SDW_MAX_DEVICES,
+				       GFP_KERNEL);
+
+	bit = find_first_zero_bit(slave->bus->assigned, SDW_MAX_DEVICES);
+	if (bit == SDW_MAX_DEVICES)
+		return -ENODEV;
+
+	return bit;
+}
+
+static void intel_put_device_num_ida(struct sdw_bus *bus, struct sdw_slave *slave)
+{
+	if (slave->prop.wake_capable || is_wake_capable(slave))
+		ida_free(&intel_peripheral_ida, slave->dev_num);
+}
+
+static struct sdw_master_ops sdw_intel_ops = {
+	.read_prop = intel_prop_read,
+	.override_adr = sdw_dmi_override_adr,
+	.xfer_msg = cdns_xfer_msg,
+	.xfer_msg_defer = cdns_xfer_msg_defer,
+	.set_bus_conf = cdns_bus_conf,
+	.pre_bank_switch = generic_pre_bank_switch,
+	.post_bank_switch = generic_post_bank_switch,
+	.read_ping_status = cdns_read_ping_status,
+	.get_device_num =  intel_get_device_num_ida,
+	.put_device_num = intel_put_device_num_ida,
+	.new_peripheral_assigned = generic_new_peripheral_assigned,
+};
+
+/*
+ * probe and init (aux_dev_id argument is required by function prototype but not used)
+ */
+static int intel_link_probe(struct auxiliary_device *auxdev,
+			    const struct auxiliary_device_id *aux_dev_id)
+
+{
+	struct device *dev = &auxdev->dev;
+	struct sdw_intel_link_dev *ldev = auxiliary_dev_to_sdw_intel_link_dev(auxdev);
+	struct sdw_intel *sdw;
+	struct sdw_cdns *cdns;
+	struct sdw_bus *bus;
+	int ret;
+
+	sdw = devm_kzalloc(dev, sizeof(*sdw), GFP_KERNEL);
+	if (!sdw)
+		return -ENOMEM;
+
+	cdns = &sdw->cdns;
+	bus = &cdns->bus;
+
+	sdw->instance = auxdev->id;
+	sdw->link_res = &ldev->link_res;
+	cdns->dev = dev;
+	cdns->registers = sdw->link_res->registers;
+	cdns->ip_offset = sdw->link_res->ip_offset;
+	cdns->instance = sdw->instance;
+	cdns->msg_count = 0;
+
+	/* single controller for all SoundWire links */
+	bus->controller_id = 0;
+
+	bus->link_id = auxdev->id;
+	bus->clk_stop_timeout = 1;
+
+	sdw_cdns_probe(cdns);
+
+	/* Set ops */
+	bus->ops = &sdw_intel_ops;
+
+	/* set driver data, accessed by snd_soc_dai_get_drvdata() */
+	auxiliary_set_drvdata(auxdev, cdns);
+
+	/* use generic bandwidth allocation algorithm */
+	sdw->cdns.bus.compute_params = sdw_compute_params;
+
+	/* avoid resuming from pm_runtime suspend if it's not required */
+	dev_pm_set_driver_flags(dev, DPM_FLAG_SMART_SUSPEND);
+
+	ret = sdw_bus_master_add(bus, dev, dev->fwnode);
+	if (ret) {
+		dev_err(dev, "sdw_bus_master_add fail: %d\n", ret);
+		return ret;
+	}
+
+	if (bus->prop.hw_disabled)
+		dev_info(dev,
+			 "SoundWire master %d is disabled, will be ignored\n",
+			 bus->link_id);
+	/*
+	 * Ignore BIOS err_threshold, it's a really bad idea when dealing
+	 * with multiple hardware synchronized links
+	 */
+	bus->prop.err_threshold = 0;
+
+	return 0;
+}
+
+int intel_link_startup(struct auxiliary_device *auxdev)
+{
+	struct device *dev = &auxdev->dev;
+	struct sdw_cdns *cdns = auxiliary_get_drvdata(auxdev);
+	struct sdw_intel *sdw = cdns_to_intel(cdns);
+	struct sdw_bus *bus = &cdns->bus;
+	int link_flags;
+	bool multi_link;
+	u32 clock_stop_quirks;
+	int ret;
+
+	if (bus->prop.hw_disabled) {
+		dev_info(dev,
+			 "SoundWire master %d is disabled, ignoring\n",
+			 sdw->instance);
+		return 0;
+	}
+
+	link_flags = md_flags >> (bus->link_id * 8);
+	multi_link = !(link_flags & SDW_INTEL_MASTER_DISABLE_MULTI_LINK);
+	if (!multi_link) {
+		dev_dbg(dev, "Multi-link is disabled\n");
+	} else {
+		/*
+		 * hardware-based synchronization is required regardless
+		 * of the number of segments used by a stream: SSP-based
+		 * synchronization is gated by gsync when the multi-master
+		 * mode is set.
+		 */
+		bus->hw_sync_min_links = 1;
+	}
+	bus->multi_link = multi_link;
+
+	/* Initialize shim, controller */
+	ret = sdw_intel_link_power_up(sdw);
+	if (ret)
+		goto err_init;
+
+	/* Register DAIs */
+	ret = sdw_intel_register_dai(sdw);
+	if (ret) {
+		dev_err(dev, "DAI registration failed: %d\n", ret);
+		goto err_power_up;
+	}
+
+	sdw_intel_debugfs_init(sdw);
+
+	/* Enable runtime PM */
+	if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME)) {
+		pm_runtime_set_autosuspend_delay(dev,
+						 INTEL_MASTER_SUSPEND_DELAY_MS);
+		pm_runtime_use_autosuspend(dev);
+		pm_runtime_mark_last_busy(dev);
+
+		pm_runtime_set_active(dev);
+		pm_runtime_enable(dev);
+
+		pm_runtime_resume(bus->dev);
+	}
+
+	/* start bus */
+	ret = sdw_intel_start_bus(sdw);
+	if (ret) {
+		dev_err(dev, "bus start failed: %d\n", ret);
+		goto err_pm_runtime;
+	}
+
+	clock_stop_quirks = sdw->link_res->clock_stop_quirks;
+	if (clock_stop_quirks & SDW_INTEL_CLK_STOP_NOT_ALLOWED) {
+		/*
+		 * To keep the clock running we need to prevent
+		 * pm_runtime suspend from happening by increasing the
+		 * reference count.
+		 * This quirk is specified by the parent PCI device in
+		 * case of specific latency requirements. It will have
+		 * no effect if pm_runtime is disabled by the user via
+		 * a module parameter for testing purposes.
+		 */
+		pm_runtime_get_noresume(dev);
+	}
+
+	/*
+	 * The runtime PM status of Slave devices is "Unsupported"
+	 * until they report as ATTACHED. If they don't, e.g. because
+	 * there are no Slave devices populated or if the power-on is
+	 * delayed or dependent on a power switch, the Master will
+	 * remain active and prevent its parent from suspending.
+	 *
+	 * Conditionally force the pm_runtime core to re-evaluate the
+	 * Master status in the absence of any Slave activity. A quirk
+	 * is provided to e.g. deal with Slaves that may be powered on
+	 * with a delay. A more complete solution would require the
+	 * definition of Master properties.
+	 */
+	if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE)) {
+		pm_runtime_mark_last_busy(bus->dev);
+		pm_runtime_mark_last_busy(dev);
+		pm_runtime_idle(dev);
+	}
+
+	sdw->startup_done = true;
+	return 0;
+
+err_pm_runtime:
+	if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME))
+		pm_runtime_disable(dev);
+err_power_up:
+	sdw_intel_link_power_down(sdw);
+err_init:
+	return ret;
+}
+
+static void intel_link_remove(struct auxiliary_device *auxdev)
+{
+	struct sdw_cdns *cdns = auxiliary_get_drvdata(auxdev);
+	struct sdw_intel *sdw = cdns_to_intel(cdns);
+	struct sdw_bus *bus = &cdns->bus;
+
+	/*
+	 * Since pm_runtime is already disabled, we don't decrease
+	 * the refcount when the clock_stop_quirk is
+	 * SDW_INTEL_CLK_STOP_NOT_ALLOWED
+	 */
+	if (!bus->prop.hw_disabled) {
+		sdw_intel_debugfs_exit(sdw);
+		sdw_cdns_enable_interrupt(cdns, false);
+	}
+	sdw_bus_master_delete(bus);
+}
+
+int intel_link_process_wakeen_event(struct auxiliary_device *auxdev)
+{
+	struct device *dev = &auxdev->dev;
+	struct sdw_intel *sdw;
+	struct sdw_bus *bus;
+
+	sdw = auxiliary_get_drvdata(auxdev);
+	bus = &sdw->cdns.bus;
+
+	if (bus->prop.hw_disabled || !sdw->startup_done) {
+		dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
+			bus->link_id);
+		return 0;
+	}
+
+	if (!sdw_intel_shim_check_wake(sdw))
+		return 0;
+
+	/* disable WAKEEN interrupt ASAP to prevent interrupt flood */
+	sdw_intel_shim_wake(sdw, false);
+
+	/*
+	 * resume the Master, which will generate a bus reset and result in
+	 * Slaves re-attaching and be re-enumerated. The SoundWire physical
+	 * device which generated the wake will trigger an interrupt, which
+	 * will in turn cause the corresponding Linux Slave device to be
+	 * resumed and the Slave codec driver to check the status.
+	 */
+	pm_request_resume(dev);
+
+	return 0;
+}
+
+/*
+ * PM calls
+ */
+
+static int intel_resume_child_device(struct device *dev, void *data)
+{
+	int ret;
+	struct sdw_slave *slave = dev_to_sdw_dev(dev);
+
+	if (!slave->probed) {
+		dev_dbg(dev, "skipping device, no probed driver\n");
+		return 0;
+	}
+	if (!slave->dev_num_sticky) {
+		dev_dbg(dev, "skipping device, never detected on bus\n");
+		return 0;
+	}
+
+	ret = pm_request_resume(dev);
+	if (ret < 0) {
+		dev_err(dev, "%s: pm_request_resume failed: %d\n", __func__, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int __maybe_unused intel_pm_prepare(struct device *dev)
+{
+	struct sdw_cdns *cdns = dev_get_drvdata(dev);
+	struct sdw_intel *sdw = cdns_to_intel(cdns);
+	struct sdw_bus *bus = &cdns->bus;
+	u32 clock_stop_quirks;
+	int ret;
+
+	if (bus->prop.hw_disabled || !sdw->startup_done) {
+		dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
+			bus->link_id);
+		return 0;
+	}
+
+	clock_stop_quirks = sdw->link_res->clock_stop_quirks;
+
+	if (pm_runtime_suspended(dev) &&
+	    pm_runtime_suspended(dev->parent) &&
+	    ((clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) ||
+	     !clock_stop_quirks)) {
+		/*
+		 * if we've enabled clock stop, and the parent is suspended, the SHIM registers
+		 * are not accessible and the shim wake cannot be disabled.
+		 * The only solution is to resume the entire bus to full power
+		 */
+
+		/*
+		 * If any operation in this block fails, we keep going since we don't want
+		 * to prevent system suspend from happening and errors should be recoverable
+		 * on resume.
+		 */
+
+		/*
+		 * first resume the device for this link. This will also by construction
+		 * resume the PCI parent device.
+		 */
+		ret = pm_request_resume(dev);
+		if (ret < 0) {
+			dev_err(dev, "%s: pm_request_resume failed: %d\n", __func__, ret);
+			return 0;
+		}
+
+		/*
+		 * Continue resuming the entire bus (parent + child devices) to exit
+		 * the clock stop mode. If there are no devices connected on this link
+		 * this is a no-op.
+		 * The resume to full power could have been implemented with a .prepare
+		 * step in SoundWire codec drivers. This would however require a lot
+		 * of code to handle an Intel-specific corner case. It is simpler in
+		 * practice to add a loop at the link level.
+		 */
+		ret = device_for_each_child(bus->dev, NULL, intel_resume_child_device);
+
+		if (ret < 0)
+			dev_err(dev, "%s: intel_resume_child_device failed: %d\n", __func__, ret);
+	}
+
+	return 0;
+}
+
+static int __maybe_unused intel_suspend(struct device *dev)
+{
+	struct sdw_cdns *cdns = dev_get_drvdata(dev);
+	struct sdw_intel *sdw = cdns_to_intel(cdns);
+	struct sdw_bus *bus = &cdns->bus;
+	u32 clock_stop_quirks;
+	int ret;
+
+	if (bus->prop.hw_disabled || !sdw->startup_done) {
+		dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
+			bus->link_id);
+		return 0;
+	}
+
+	if (pm_runtime_suspended(dev)) {
+		dev_dbg(dev, "pm_runtime status: suspended\n");
+
+		clock_stop_quirks = sdw->link_res->clock_stop_quirks;
+
+		if ((clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) ||
+		    !clock_stop_quirks) {
+
+			if (pm_runtime_suspended(dev->parent)) {
+				/*
+				 * paranoia check: this should not happen with the .prepare
+				 * resume to full power
+				 */
+				dev_err(dev, "%s: invalid config: parent is suspended\n", __func__);
+			} else {
+				sdw_intel_shim_wake(sdw, false);
+			}
+		}
+
+		return 0;
+	}
+
+	ret = sdw_intel_stop_bus(sdw, false);
+	if (ret < 0) {
+		dev_err(dev, "%s: cannot stop bus: %d\n", __func__, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+static int __maybe_unused intel_suspend_runtime(struct device *dev)
+{
+	struct sdw_cdns *cdns = dev_get_drvdata(dev);
+	struct sdw_intel *sdw = cdns_to_intel(cdns);
+	struct sdw_bus *bus = &cdns->bus;
+	u32 clock_stop_quirks;
+	int ret;
+
+	if (bus->prop.hw_disabled || !sdw->startup_done) {
+		dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
+			bus->link_id);
+		return 0;
+	}
+
+	clock_stop_quirks = sdw->link_res->clock_stop_quirks;
+
+	if (clock_stop_quirks & SDW_INTEL_CLK_STOP_TEARDOWN) {
+		ret = sdw_intel_stop_bus(sdw, false);
+		if (ret < 0) {
+			dev_err(dev, "%s: cannot stop bus during teardown: %d\n",
+				__func__, ret);
+			return ret;
+		}
+	} else if (clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET || !clock_stop_quirks) {
+		ret = sdw_intel_stop_bus(sdw, true);
+		if (ret < 0) {
+			dev_err(dev, "%s: cannot stop bus during clock_stop: %d\n",
+				__func__, ret);
+			return ret;
+		}
+	} else {
+		dev_err(dev, "%s clock_stop_quirks %x unsupported\n",
+			__func__, clock_stop_quirks);
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static int __maybe_unused intel_resume(struct device *dev)
+{
+	struct sdw_cdns *cdns = dev_get_drvdata(dev);
+	struct sdw_intel *sdw = cdns_to_intel(cdns);
+	struct sdw_bus *bus = &cdns->bus;
+	int link_flags;
+	int ret;
+
+	if (bus->prop.hw_disabled || !sdw->startup_done) {
+		dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
+			bus->link_id);
+		return 0;
+	}
+
+	link_flags = md_flags >> (bus->link_id * 8);
+
+	if (pm_runtime_suspended(dev)) {
+		dev_dbg(dev, "pm_runtime status was suspended, forcing active\n");
+
+		/* follow required sequence from runtime_pm.rst */
+		pm_runtime_disable(dev);
+		pm_runtime_set_active(dev);
+		pm_runtime_mark_last_busy(dev);
+		pm_runtime_enable(dev);
+
+		pm_runtime_resume(bus->dev);
+
+		link_flags = md_flags >> (bus->link_id * 8);
+
+		if (!(link_flags & SDW_INTEL_MASTER_DISABLE_PM_RUNTIME_IDLE))
+			pm_runtime_idle(dev);
+	}
+
+	ret = sdw_intel_link_power_up(sdw);
+	if (ret) {
+		dev_err(dev, "%s failed: %d\n", __func__, ret);
+		return ret;
+	}
+
+	/*
+	 * make sure all Slaves are tagged as UNATTACHED and provide
+	 * reason for reinitialization
+	 */
+	sdw_clear_slave_status(bus, SDW_UNATTACH_REQUEST_MASTER_RESET);
+
+	ret = sdw_intel_start_bus(sdw);
+	if (ret < 0) {
+		dev_err(dev, "cannot start bus during resume\n");
+		sdw_intel_link_power_down(sdw);
+		return ret;
+	}
+
+	/*
+	 * after system resume, the pm_runtime suspend() may kick in
+	 * during the enumeration, before any children device force the
+	 * master device to remain active.  Using pm_runtime_get()
+	 * routines is not really possible, since it'd prevent the
+	 * master from suspending.
+	 * A reasonable compromise is to update the pm_runtime
+	 * counters and delay the pm_runtime suspend by several
+	 * seconds, by when all enumeration should be complete.
+	 */
+	pm_runtime_mark_last_busy(bus->dev);
+	pm_runtime_mark_last_busy(dev);
+
+	return 0;
+}
+
+static int __maybe_unused intel_resume_runtime(struct device *dev)
+{
+	struct sdw_cdns *cdns = dev_get_drvdata(dev);
+	struct sdw_intel *sdw = cdns_to_intel(cdns);
+	struct sdw_bus *bus = &cdns->bus;
+	u32 clock_stop_quirks;
+	int ret;
+
+	if (bus->prop.hw_disabled || !sdw->startup_done) {
+		dev_dbg(dev, "SoundWire master %d is disabled or not-started, ignoring\n",
+			bus->link_id);
+		return 0;
+	}
+
+	/* unconditionally disable WAKEEN interrupt */
+	sdw_intel_shim_wake(sdw, false);
+
+	clock_stop_quirks = sdw->link_res->clock_stop_quirks;
+
+	if (clock_stop_quirks & SDW_INTEL_CLK_STOP_TEARDOWN) {
+		ret = sdw_intel_link_power_up(sdw);
+		if (ret) {
+			dev_err(dev, "%s: power_up failed after teardown: %d\n", __func__, ret);
+			return ret;
+		}
+
+		/*
+		 * make sure all Slaves are tagged as UNATTACHED and provide
+		 * reason for reinitialization
+		 */
+		sdw_clear_slave_status(bus, SDW_UNATTACH_REQUEST_MASTER_RESET);
+
+		ret = sdw_intel_start_bus(sdw);
+		if (ret < 0) {
+			dev_err(dev, "%s: cannot start bus after teardown: %d\n", __func__, ret);
+			sdw_intel_link_power_down(sdw);
+			return ret;
+		}
+
+	} else if (clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) {
+		ret = sdw_intel_link_power_up(sdw);
+		if (ret) {
+			dev_err(dev, "%s: power_up failed after bus reset: %d\n", __func__, ret);
+			return ret;
+		}
+
+		ret = sdw_intel_start_bus_after_reset(sdw);
+		if (ret < 0) {
+			dev_err(dev, "%s: cannot start bus after reset: %d\n", __func__, ret);
+			sdw_intel_link_power_down(sdw);
+			return ret;
+		}
+	} else if (!clock_stop_quirks) {
+
+		sdw_intel_check_clock_stop(sdw);
+
+		ret = sdw_intel_link_power_up(sdw);
+		if (ret) {
+			dev_err(dev, "%s: power_up failed: %d\n", __func__, ret);
+			return ret;
+		}
+
+		ret = sdw_intel_start_bus_after_clock_stop(sdw);
+		if (ret < 0) {
+			dev_err(dev, "%s: cannot start bus after clock stop: %d\n", __func__, ret);
+			sdw_intel_link_power_down(sdw);
+			return ret;
+		}
+	} else {
+		dev_err(dev, "%s: clock_stop_quirks %x unsupported\n",
+			__func__, clock_stop_quirks);
+		ret = -EINVAL;
+	}
+
+	return ret;
+}
+
+static const struct dev_pm_ops intel_pm = {
+	.prepare = intel_pm_prepare,
+	SET_SYSTEM_SLEEP_PM_OPS(intel_suspend, intel_resume)
+	SET_RUNTIME_PM_OPS(intel_suspend_runtime, intel_resume_runtime, NULL)
+};
+
+static const struct auxiliary_device_id intel_link_id_table[] = {
+	{ .name = "soundwire_intel.link" },
+	{},
+};
+MODULE_DEVICE_TABLE(auxiliary, intel_link_id_table);
+
+static struct auxiliary_driver sdw_intel_drv = {
+	.probe = intel_link_probe,
+	.remove = intel_link_remove,
+	.driver = {
+		/* auxiliary_driver_register() sets .name to be the modname */
+		.pm = &intel_pm,
+	},
+	.id_table = intel_link_id_table
+};
+module_auxiliary_driver(sdw_intel_drv);
+
+MODULE_LICENSE("Dual BSD/GPL");
+MODULE_DESCRIPTION("Intel Soundwire Link Driver");