From: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com

Add basic hooks in DAI .startup and .shutdown callbacks.

The SoundWire IP should be powered between those two calls. The power dependencies between SoundWire and DSP are handled with the parent/child relationship, before the SoundWire master device becomes active the parent device will become active and power-up the shared rails.

For now the strategy is to rely on complete enumeration when the device becomes active, so the code is a copy/paste of the sequence for system suspend/resume. In future patches, the strategy will optionally be to rely on clock stop if the enumeration time is prohibitive or when the devices connected to a link can signal a wake.

A module parameter is added to make integration of new Slave devices easier, to e.g. keep the device active or prevent clock-stop.

Note that we need to we have to disable runtime pm before device unregister, otherwise we will see "Failed to power up link: -11" error on module remove test.

Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Signed-off-by: Bard Liao yung-chuan.liao@linux.intel.com --- drivers/soundwire/intel.c | 112 +++++++++++++++++++++++++++++++-- drivers/soundwire/intel_init.c | 5 +- 2 files changed, 112 insertions(+), 5 deletions(-)

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index 88aeef8b7c0c..85a0bb6af4fe 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -22,6 +22,22 @@ #include "bus.h" #include "intel.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) + +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)"); + /* Intel SHIM Registers Definition */ #define SDW_SHIM_LCAP 0x0 #define SDW_SHIM_LCTL 0x4 @@ -807,10 +823,17 @@ static int intel_post_bank_switch(struct sdw_bus *bus) static int intel_startup(struct snd_pcm_substream *substream, struct snd_soc_dai *dai) { - /* - * TODO: add pm_runtime support here, the startup callback - * will make sure the IP is 'active' - */ + struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai); + int ret; + + ret = pm_runtime_get_sync(cdns->dev); + if (ret < 0 && ret != -EACCES) { + dev_err_ratelimited(cdns->dev, + "pm_runtime_get_sync failed in %s, ret %d\n", + __func__, ret); + pm_runtime_put_noidle(cdns->dev); + return ret; + } return 0; }

@@ -985,7 +1008,10 @@ intel_hw_free(struct snd_pcm_substream *substream, struct snd_soc_dai *dai) static void intel_shutdown(struct snd_pcm_substream *substream, struct snd_soc_dai *dai) { + struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai);

+ pm_runtime_mark_last_busy(cdns->dev); + pm_runtime_put_autosuspend(cdns->dev); }

static int intel_pcm_set_sdw_stream(struct snd_soc_dai *dai, @@ -1270,6 +1296,7 @@ int intel_master_startup(struct platform_device *pdev) 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) { @@ -1314,6 +1341,18 @@ int intel_master_startup(struct platform_device *pdev)

intel_debugfs_init(sdw);

+ /* Enable runtime PM */ + link_flags = md_flags >> (bus->link_id * 8); + 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); + } + return 0;

err_interrupt: @@ -1412,6 +1451,36 @@ static int intel_suspend(struct device *dev) return 0; }

+static int 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; + int ret; + + if (bus->prop.hw_disabled) { + dev_dbg(dev, "SoundWire master %d is disabled, ignoring\n", + bus->link_id); + return 0; + } + + ret = sdw_cdns_enable_interrupt(cdns, false); + if (ret < 0) { + dev_err(dev, "cannot disable interrupts on suspend\n"); + return ret; + } + + ret = intel_link_power_down(sdw); + if (ret) { + dev_err(dev, "Link power down failed: %d", ret); + return ret; + } + + intel_shim_wake(sdw, false); + + return 0; +} + static int intel_resume(struct device *dev) { struct sdw_cdns *cdns = dev_get_drvdata(dev); @@ -1446,10 +1515,45 @@ static int intel_resume(struct device *dev) return ret; }

+static int 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; + int ret; + + if (bus->prop.hw_disabled) { + dev_dbg(dev, "SoundWire master %d is disabled, ignoring\n", + bus->link_id); + return 0; + } + + ret = intel_init(sdw); + if (ret) { + dev_err(dev, "%s failed: %d", __func__, ret); + return ret; + } + + ret = sdw_cdns_enable_interrupt(cdns, true); + if (ret < 0) { + dev_err(dev, "cannot enable interrupts during resume\n"); + return ret; + } + + ret = sdw_cdns_exit_reset(cdns); + if (ret < 0) { + dev_err(dev, "unable to exit bus reset sequence during resume\n"); + return ret; + } + + return ret; +} + #endif

static const struct dev_pm_ops intel_pm = { SET_SYSTEM_SLEEP_PM_OPS(intel_suspend, intel_resume) + SET_RUNTIME_PM_OPS(intel_suspend_runtime, intel_resume_runtime, NULL) };

static struct platform_driver sdw_intel_drv = { diff --git a/drivers/soundwire/intel_init.c b/drivers/soundwire/intel_init.c index 047252a91c9e..a1f210853545 100644 --- a/drivers/soundwire/intel_init.c +++ b/drivers/soundwire/intel_init.c @@ -13,6 +13,7 @@ #include <linux/io.h> #include <linux/module.h> #include <linux/platform_device.h> +#include <linux/pm_runtime.h> #include <linux/soundwire/sdw_intel.h> #include "cadence_master.h" #include "intel.h" @@ -68,8 +69,10 @@ static int sdw_intel_cleanup(struct sdw_intel_ctx *ctx) if (!(link_mask & BIT(i))) continue;

- if (link->pdev) + if (link->pdev) { + pm_runtime_disable(&link->pdev->dev); platform_device_unregister(link->pdev); + } }

return 0;

From: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com

Previous patches took care of the case where the master device is pm_runtime 'suspended' when a system suspend occurs.

In the case where the master device was not suspended, e.g. if suspend occurred while streaming audio, Intel validation noticed a race condition: the pm_runtime suspend may conflict with the enumeration started by the system resume.

This can be simply fixed by updating the status before exiting system resume.

GitHub issue: https://github.com/thesofproject/linux/issues/1482 Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Signed-off-by: Bard Liao yung-chuan.liao@linux.intel.com --- drivers/soundwire/intel.c | 12 ++++++++++++ 1 file changed, 12 insertions(+)

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index 0e21bae3cd19..00c5de1250ec 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -1528,6 +1528,18 @@ static int intel_resume(struct device *dev) 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(dev); + return ret; }

The .prepare() callback is invoked for normal streaming, underflows or during the system resume transition. In the latter case, the context for the ALH PDIs is lost, and the DSP is not initialized properly either, but the bus parameters don't need to be recomputed.

Conversely, when doing a regular .prepare() during an underflow, the ALH/SHIM registers shall not be changed as the hardware cannot be reprogrammed after the DMA started (hardware spec requirement).

This patch adds storage of PDI and hw_params in the DAI dma context, and the difference between the types of .prepare() usages is handled via a simple boolean, updated when suspending, and tested for in the .prepare() case.

Signed-off-by: Bard Liao yung-chuan.liao@linux.intel.com Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com --- drivers/soundwire/cadence_master.h | 4 ++ drivers/soundwire/intel.c | 71 +++++++++++++++++++++++++++++- 2 files changed, 74 insertions(+), 1 deletion(-)

diff --git a/drivers/soundwire/cadence_master.h b/drivers/soundwire/cadence_master.h index 7638858397df..fdec62b912d3 100644 --- a/drivers/soundwire/cadence_master.h +++ b/drivers/soundwire/cadence_master.h @@ -84,6 +84,8 @@ struct sdw_cdns_stream_config { * @bus: Bus handle * @stream_type: Stream type * @link_id: Master link id + * @hw_params: hw_params to be applied in .prepare step + * @suspended: status set when suspended, to be used in .prepare */ struct sdw_cdns_dma_data { char *name; @@ -92,6 +94,8 @@ struct sdw_cdns_dma_data { struct sdw_bus *bus; enum sdw_stream_type stream_type; int link_id; + struct snd_pcm_hw_params *hw_params; + bool suspended; };

/** diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index 10dd0e208ce7..95a1d88a5bfb 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -879,6 +879,10 @@ static int intel_hw_params(struct snd_pcm_substream *substream, intel_pdi_alh_configure(sdw, pdi); sdw_cdns_config_stream(cdns, ch, dir, pdi);

+ /* store pdi and hw_params, may be needed in prepare step */ + dma->suspended = false; + dma->pdi = pdi; + dma->hw_params = params;

/* Inform DSP about PDI stream number */ ret = intel_params_stream(sdw, substream, dai, params, @@ -922,7 +926,11 @@ static int intel_hw_params(struct snd_pcm_substream *substream, static int intel_prepare(struct snd_pcm_substream *substream, struct snd_soc_dai *dai) { + struct sdw_cdns *cdns = snd_soc_dai_get_drvdata(dai); + struct sdw_intel *sdw = cdns_to_intel(cdns); struct sdw_cdns_dma_data *dma; + int ch, dir; + int ret;

dma = snd_soc_dai_get_dma_data(dai, substream); if (!dma) { @@ -931,7 +939,41 @@ static int intel_prepare(struct snd_pcm_substream *substream, return -EIO; }

- return sdw_prepare_stream(dma->stream); + if (dma->suspended) { + dma->suspended = false; + + /* + * .prepare() is called after system resume, where we + * need to reinitialize the SHIM/ALH/Cadence IP. + * .prepare() is also called to deal with underflows, + * but in those cases we cannot touch ALH/SHIM + * registers + */ + + /* configure stream */ + ch = params_channels(dma->hw_params); + if (substream->stream == SNDRV_PCM_STREAM_CAPTURE) + dir = SDW_DATA_DIR_RX; + else + dir = SDW_DATA_DIR_TX; + + intel_pdi_shim_configure(sdw, dma->pdi); + intel_pdi_alh_configure(sdw, dma->pdi); + sdw_cdns_config_stream(cdns, ch, dir, dma->pdi); + + /* Inform DSP about PDI stream number */ + ret = intel_params_stream(sdw, substream, dai, + dma->hw_params, + sdw->instance, + dma->pdi->intel_alh_id); + if (ret) + goto err; + } + + ret = sdw_prepare_stream(dma->stream); + +err: + return ret; }

static int intel_trigger(struct snd_pcm_substream *substream, int cmd, @@ -1002,6 +1044,9 @@ intel_hw_free(struct snd_pcm_substream *substream, struct snd_soc_dai *dai) return ret; }

+ dma->hw_params = NULL; + dma->pdi = NULL; + return 0; }

@@ -1014,6 +1059,29 @@ static void intel_shutdown(struct snd_pcm_substream *substream, pm_runtime_put_autosuspend(cdns->dev); }

+static int intel_component_dais_suspend(struct snd_soc_component *component) +{ + struct sdw_cdns_dma_data *dma; + struct snd_soc_dai *dai; + + for_each_component_dais(component, dai) { + /* + * we don't have a .suspend dai_ops, and we don't have access + * to the substream, so let's mark both capture and playback + * DMA contexts as suspended + */ + dma = dai->playback_dma_data; + if (dma) + dma->suspended = true; + + dma = dai->capture_dma_data; + if (dma) + dma->suspended = true; + } + + return 0; +} + static int intel_pcm_set_sdw_stream(struct snd_soc_dai *dai, void *stream, int direction) { @@ -1066,6 +1134,7 @@ static const struct snd_soc_dai_ops intel_pdm_dai_ops = {

static const struct snd_soc_component_driver dai_component = { .name = "soundwire", + .suspend = intel_component_dais_suspend };

static int intel_create_dai(struct sdw_cdns *cdns,

From: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com

Now that we have options, add support for TEARDOWN mode (same functionality as existing code)

All other modes will be added in follow-up patches.

Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Signed-off-by: Bard Liao yung-chuan.liao@linux.intel.com --- drivers/soundwire/intel.c | 82 +++++++++++++++++++++------------- drivers/soundwire/intel.h | 2 + drivers/soundwire/intel_init.c | 1 + 3 files changed, 54 insertions(+), 31 deletions(-)

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index 3f9015dcb693..68c1cdfb7999 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -1548,6 +1548,7 @@ static int 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) { @@ -1556,21 +1557,31 @@ static int intel_suspend_runtime(struct device *dev) return 0; }

- ret = sdw_cdns_enable_interrupt(cdns, false); - if (ret < 0) { - dev_err(dev, "cannot disable interrupts on suspend\n"); - return ret; - } + clock_stop_quirks = sdw->link_res->clock_stop_quirks;

- ret = intel_link_power_down(sdw); - if (ret) { - dev_err(dev, "Link power down failed: %d", ret); - return ret; - } + if (clock_stop_quirks & SDW_INTEL_CLK_STOP_TEARDOWN) { + + ret = sdw_cdns_enable_interrupt(cdns, false); + if (ret < 0) { + dev_err(dev, "cannot disable interrupts on suspend\n"); + return ret; + }

- intel_shim_wake(sdw, false); + ret = intel_link_power_down(sdw); + if (ret) { + dev_err(dev, "Link power down failed: %d", ret); + return ret; + } + + intel_shim_wake(sdw, false); + + } else { + dev_err(dev, "%s clock_stop_quirks %x unsupported\n", + __func__, clock_stop_quirks); + ret = -EINVAL; + }

- return 0; + return ret; }

static int intel_resume(struct device *dev) @@ -1645,6 +1656,7 @@ static int 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) { @@ -1653,28 +1665,36 @@ static int intel_resume_runtime(struct device *dev) return 0; }

- ret = intel_init(sdw); - if (ret) { - dev_err(dev, "%s failed: %d", __func__, ret); - return ret; - } + clock_stop_quirks = sdw->link_res->clock_stop_quirks;

- /* - * make sure all Slaves are tagged as UNATTACHED and provide - * reason for reinitialization - */ - sdw_clear_slave_status(bus, SDW_UNATTACH_REQUEST_MASTER_RESET); + if (clock_stop_quirks & SDW_INTEL_CLK_STOP_TEARDOWN) { + ret = intel_init(sdw); + if (ret) { + dev_err(dev, "%s failed: %d", __func__, ret); + return ret; + }

- ret = sdw_cdns_enable_interrupt(cdns, true); - if (ret < 0) { - dev_err(dev, "cannot enable interrupts during resume\n"); - 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_cdns_exit_reset(cdns); - if (ret < 0) { - dev_err(dev, "unable to exit bus reset sequence during resume\n"); - return ret; + ret = sdw_cdns_enable_interrupt(cdns, true); + if (ret < 0) { + dev_err(dev, "cannot enable interrupts during resume\n"); + return ret; + } + + ret = sdw_cdns_exit_reset(cdns); + if (ret < 0) { + dev_err(dev, "unable to exit bus reset sequence during resume\n"); + return ret; + } + } else { + dev_err(dev, "%s clock_stop_quirks %x unsupported\n", + __func__, clock_stop_quirks); + ret = -EINVAL; }

return ret; diff --git a/drivers/soundwire/intel.h b/drivers/soundwire/intel.h index 4ea3d262d249..23daab9da329 100644 --- a/drivers/soundwire/intel.h +++ b/drivers/soundwire/intel.h @@ -17,6 +17,7 @@ * @dev: device implementing hw_params and free callbacks * @shim_lock: mutex to handle access to shared SHIM registers * @shim_mask: global pointer to check SHIM register initialization + * @clock_stop_quirks: mask defining requested behavior on pm_suspend * @cdns: Cadence master descriptor * @list: used to walk-through all masters exposed by the same controller */ @@ -31,6 +32,7 @@ struct sdw_intel_link_res { struct device *dev; struct mutex *shim_lock; /* protect shared registers */ u32 *shim_mask; + u32 clock_stop_quirks; struct sdw_cdns *cdns; struct list_head list; }; diff --git a/drivers/soundwire/intel_init.c b/drivers/soundwire/intel_init.c index a1f210853545..dd1050743dca 100644 --- a/drivers/soundwire/intel_init.c +++ b/drivers/soundwire/intel_init.c @@ -249,6 +249,7 @@ static struct sdw_intel_ctx link->ops = res->ops; link->dev = res->dev;

+ link->clock_stop_quirks = res->clock_stop_quirks; link->shim_lock = &ctx->shim_lock; link->shim_mask = &ctx->shim_mask;

From: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com

In case the clock needs to keep running, we need to prevent the Master from entering pm_runtime suspend.

Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Signed-off-by: Bard Liao yung-chuan.liao@linux.intel.com --- drivers/soundwire/intel.c | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+)

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index ad476e9e4d25..95b14c034ea7 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -1367,6 +1367,7 @@ int intel_master_startup(struct platform_device *pdev) struct sdw_intel *sdw = cdns_to_intel(cdns); struct sdw_bus *bus = &cdns->bus; int link_flags; + u32 clock_stop_quirks; int ret;

if (bus->prop.hw_disabled) { @@ -1423,6 +1424,20 @@ int intel_master_startup(struct platform_device *pdev) pm_runtime_enable(dev); }

+ 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 @@ -1454,6 +1469,11 @@ static int intel_master_remove(struct platform_device *pdev) 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) { intel_debugfs_exit(sdw); sdw_cdns_enable_interrupt(cdns, false);

From: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com

In this mode, on restart the bus restarts immediately, the Slaves remain synchronized and all context is kept intact.

Signed-off-by: Pierre-Louis Bossart pierre-louis.bossart@linux.intel.com Signed-off-by: Rander Wang rander.wang@intel.com Signed-off-by: Bard Liao yung-chuan.liao@linux.intel.com --- drivers/soundwire/intel.c | 21 ++++++++++++++++++++- 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/drivers/soundwire/intel.c b/drivers/soundwire/intel.c index 95b14c034ea7..2899445e2649 100644 --- a/drivers/soundwire/intel.c +++ b/drivers/soundwire/intel.c @@ -1595,7 +1595,8 @@ static int intel_suspend_runtime(struct device *dev)

intel_shim_wake(sdw, false);

- } else if (clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET) { + } else if (clock_stop_quirks & SDW_INTEL_CLK_STOP_BUS_RESET || + !clock_stop_quirks) { ret = sdw_cdns_clock_stop(cdns, true); if (ret < 0) { dev_err(dev, "cannot enable clock stop on suspend\n"); @@ -1755,6 +1756,24 @@ static int intel_resume_runtime(struct device *dev) dev_err(dev, "unable to restart clock during resume\n"); return ret; } + } else if (!clock_stop_quirks) { + ret = intel_init(sdw); + if (ret) { + dev_err(dev, "%s failed: %d", __func__, ret); + return ret; + } + + ret = sdw_cdns_enable_interrupt(cdns, true); + if (ret < 0) { + dev_err(dev, "cannot enable interrupts during resume\n"); + return ret; + } + + ret = sdw_cdns_clock_restart(cdns, false); + if (ret < 0) { + dev_err(dev, "unable to resume master during resume\n"); + return ret; + } } else { dev_err(dev, "%s clock_stop_quirks %x unsupported\n", __func__, clock_stop_quirks);