// 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)");

static int mclk_divider;
module_param_named(sdw_mclk_divider, mclk_divider, int, 0444);
MODULE_PARM_DESC(sdw_mclk_divider, "SoundWire Intel mclk divider");

struct wake_capable_part {
        const u16 mfg_id;
        const u16 part_id;
};

static struct wake_capable_part wake_capable_list[] = {
        {0x01fa, 0x4243},
        {0x01fa, 0x4245},
        {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, 0x721},
        {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_bpt_send_async(struct sdw_bus *bus, struct sdw_slave *slave,
                                  struct sdw_bpt_msg *msg)
{
        struct sdw_cdns *cdns = bus_to_cdns(bus);
        struct sdw_intel *sdw = cdns_to_intel(cdns);

        if (sdw->link_res->hw_ops->bpt_send_async)
                return sdw->link_res->hw_ops->bpt_send_async(sdw, slave, msg);
        return -EOPNOTSUPP;
}

static int generic_bpt_wait(struct sdw_bus *bus, struct sdw_slave *slave, struct sdw_bpt_msg *msg)
{
        struct sdw_cdns *cdns = bus_to_cdns(bus);
        struct sdw_intel *sdw = cdns_to_intel(cdns);

        if (sdw->link_res->hw_ops->bpt_wait)
                return sdw->link_res->hw_ops->bpt_wait(sdw, slave, msg);
        return -EOPNOTSUPP;
}

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 sdw_intel_prop *intel_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);

        if (mclk_divider)
                /* use kernel parameter for BIOS or board work-arounds */
                prop->mclk_freq /= mclk_divider;
        else
                /* 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;

        intel_prop = devm_kzalloc(bus->dev, sizeof(*intel_prop), GFP_KERNEL);
        if (!intel_prop) {
                fwnode_handle_put(link);
                return -ENOMEM;
        }

        /* initialize with hardware defaults, in case the properties are not found */
        intel_prop->clde = 0x0;
        intel_prop->doaise2 = 0x0;
        intel_prop->dodse2 = 0x0;
        intel_prop->clds = 0x0;
        intel_prop->clss = 0x0;
        intel_prop->doaise = 0x1;
        intel_prop->doais = 0x3;
        intel_prop->dodse  = 0x0;
        intel_prop->dods  = 0x1;

        fwnode_property_read_u16(link,
                                 "intel-sdw-clde",
                                 &intel_prop->clde);
        fwnode_property_read_u16(link,
                                 "intel-sdw-doaise2",
                                 &intel_prop->doaise2);
        fwnode_property_read_u16(link,
                                 "intel-sdw-dodse2",
                                 &intel_prop->dodse2);
        fwnode_property_read_u16(link,
                                 "intel-sdw-clds",
                                 &intel_prop->clds);
        fwnode_property_read_u16(link,
                                 "intel-sdw-clss",
                                 &intel_prop->clss);
        fwnode_property_read_u16(link,
                                 "intel-sdw-doaise",
                                 &intel_prop->doaise);
        fwnode_property_read_u16(link,
                                 "intel-sdw-doais",
                                 &intel_prop->doais);
        fwnode_property_read_u16(link,
                                 "intel-sdw-dodse",
                                 &intel_prop->dodse);
        fwnode_property_read_u16(link,
                                 "intel-sdw-dods",
                                 &intel_prop->dods);
        bus->vendor_specific_prop = intel_prop;

        dev_dbg(bus->dev, "doaise %#x doais %#x dodse %#x dods %#x\n",
                intel_prop->doaise,
                intel_prop->doais,
                intel_prop->dodse,
                intel_prop->dods);

        fwnode_handle_put(link);

        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,

        .bpt_send_async = generic_bpt_send_async,
        .bpt_wait = generic_bpt_wait,
};

/*
 * 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;

        /*
         * paranoia check: make sure ACPI-reported number of links is aligned with
         * hardware capabilities.
         */
        ret = sdw_intel_get_link_count(sdw);
        if (ret < 0) {
                dev_err(dev, "%s: sdw_intel_get_link_count failed: %d\n", __func__, ret);
                return ret;
        }
        if (ret <= sdw->instance) {
                dev_err(dev, "%s: invalid link id %d, link count %d\n", __func__, auxdev->id, ret);
                return -EINVAL;
        }

        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;

        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);
                cancel_delayed_work_sync(&cdns->attach_dwork);
                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
 */

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_runtime_resume(dev);
        if (ret < 0) {
                dev_err(dev, "%s: pm_runtime_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_runtime_resume(dev);
                if (ret < 0) {
                        dev_err(dev, "%s: pm_runtime_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;
        }

        /* Prevent runtime PM from racing with the code below. */
        pm_runtime_disable(dev);

        if (pm_runtime_status_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_status_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 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;
        }

        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;
        }

        /*
         * Runtime PM has been disabled in intel_suspend(), so set the status
         * to active because the device has just been resumed and re-enable
         * runtime PM.
         */
        pm_runtime_set_active(dev);
        pm_runtime_enable(dev);

        /*
         * 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");