From d9a2b5eaec9424e6db0142e07c1b3de17fb81b88 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Fri, 12 Jul 2024 16:07:59 +0200 Subject: [PATCH 1/5] soundwire: bus: suppress probe deferral errors Soundwire driver probe errors are currently being logged both by the bus code and driver core: wsa884x-codec sdw:4:0:0217:0204:00:0: Probe of wsa884x-codec failed: -12 wsa884x-codec sdw:4:0:0217:0204:00:0: probe with driver wsa884x-codec failed with error -12 Drop the redundant bus error message, which is also incorrectly being logged on probe deferral: wsa884x-codec sdw:4:0:0217:0204:00:0: Probe of wsa884x-codec failed: -517 Note that no soundwire driver uses the driver struct name field, which will be removed by a follow-on change. Signed-off-by: Johan Hovold Reviewed-by: Pierre-Louis Bossart Link: https://lore.kernel.org/r/20240712140801.24267-2-johan+linaro@kernel.org Signed-off-by: Vinod Koul --- drivers/soundwire/bus_type.c | 6 ------ 1 file changed, 6 deletions(-) diff --git a/drivers/soundwire/bus_type.c b/drivers/soundwire/bus_type.c index d928258c6761..6b1c8c817102 100644 --- a/drivers/soundwire/bus_type.c +++ b/drivers/soundwire/bus_type.c @@ -83,7 +83,6 @@ static int sdw_drv_probe(struct device *dev) struct sdw_slave *slave = dev_to_sdw_dev(dev); struct sdw_driver *drv = drv_to_sdw_driver(dev->driver); const struct sdw_device_id *id; - const char *name; int ret; /* @@ -108,11 +107,6 @@ static int sdw_drv_probe(struct device *dev) ret = drv->probe(slave, id); if (ret) { - name = drv->name; - if (!name) - name = drv->driver.name; - - dev_err(dev, "Probe of %s failed: %d\n", name, ret); dev_pm_domain_detach(dev, false); return ret; } From 6dfbafd8a1d51a52a623d912a2219e9982020854 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Fri, 12 Jul 2024 16:08:00 +0200 Subject: [PATCH 2/5] soundwire: bus: drop unused driver name field The soundwire driver name field is not currently used by any driver (and even appears to never have been used) so drop it. Signed-off-by: Johan Hovold Reviewed-by: Pierre-Louis Bossart Link: https://lore.kernel.org/r/20240712140801.24267-3-johan+linaro@kernel.org Signed-off-by: Vinod Koul --- drivers/soundwire/bus_type.c | 9 ++------- include/linux/soundwire/sdw.h | 2 -- 2 files changed, 2 insertions(+), 9 deletions(-) diff --git a/drivers/soundwire/bus_type.c b/drivers/soundwire/bus_type.c index 6b1c8c817102..fe08f7644f0e 100644 --- a/drivers/soundwire/bus_type.c +++ b/drivers/soundwire/bus_type.c @@ -198,16 +198,11 @@ static void sdw_drv_shutdown(struct device *dev) */ int __sdw_register_driver(struct sdw_driver *drv, struct module *owner) { - const char *name; - drv->driver.bus = &sdw_bus_type; if (!drv->probe) { - name = drv->name; - if (!name) - name = drv->driver.name; - - pr_err("driver %s didn't provide SDW probe routine\n", name); + pr_err("driver %s didn't provide SDW probe routine\n", + drv->driver.name); return -EINVAL; } diff --git a/include/linux/soundwire/sdw.h b/include/linux/soundwire/sdw.h index 94fc1b57c57b..5e0dd47a0412 100644 --- a/include/linux/soundwire/sdw.h +++ b/include/linux/soundwire/sdw.h @@ -704,8 +704,6 @@ struct sdw_master_device { container_of(d, struct sdw_master_device, dev) struct sdw_driver { - const char *name; - int (*probe)(struct sdw_slave *sdw, const struct sdw_device_id *id); int (*remove)(struct sdw_slave *sdw); From 663229e24255883f010ae4d94f9f8e9c34e57d6c Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Fri, 12 Jul 2024 16:08:01 +0200 Subject: [PATCH 3/5] soundwire: bus: clean up probe warnings Clean up the probe warning messages by using a common succinct and greppable format (e.g. without __func__ and with a space after ':'). Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20240712140801.24267-4-johan+linaro@kernel.org Signed-off-by: Vinod Koul --- drivers/soundwire/bus_type.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/soundwire/bus_type.c b/drivers/soundwire/bus_type.c index fe08f7644f0e..77dc094075e1 100644 --- a/drivers/soundwire/bus_type.c +++ b/drivers/soundwire/bus_type.c @@ -123,7 +123,7 @@ static int sdw_drv_probe(struct device *dev) /* init the dynamic sysfs attributes we need */ ret = sdw_slave_sysfs_dpn_init(slave); if (ret < 0) - dev_warn(dev, "Slave sysfs init failed:%d\n", ret); + dev_warn(dev, "failed to initialise sysfs: %d\n", ret); /* * Check for valid clk_stop_timeout, use DisCo worst case value of @@ -147,7 +147,7 @@ static int sdw_drv_probe(struct device *dev) if (drv->ops && drv->ops->update_status) { ret = drv->ops->update_status(slave, slave->status); if (ret < 0) - dev_warn(dev, "%s: update_status failed with status %d\n", __func__, ret); + dev_warn(dev, "failed to update status at probe: %d\n", ret); } mutex_unlock(&slave->sdw_dev_lock); From f8c35d61ba01afa76846905c67862cdace7f66b0 Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Mon, 5 Aug 2024 19:49:21 +0800 Subject: [PATCH 4/5] soundwire: cadence: re-check Peripheral status with delayed_work The SoundWire peripheral enumeration is entirely based on interrupts, more specifically sticky bits tracking state changes. This patch adds a defensive programming check on the actual status reported in PING frames. If for some reason an interrupt was lost or delayed, the delayed work would detect a peripheral change of status after the bus starts. The 100ms defined for the delay is not completely arbitrary, if a Peripheral didn't join the bus within that delay then probably the hardware link is broken, and conversely if the detection didn't happen because of software issues the 100ms is still acceptable in terms of user experience. The overhead of the one-shot workqueue is minimal, and the mutual exclusion ensures that the interrupt and delayed work cannot update the status concurrently. Reviewed-by: Liam Girdwood Signed-off-by: Pierre-Louis Bossart Signed-off-by: Bard Liao Link: https://lore.kernel.org/r/20240805114921.88007-1-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul --- drivers/soundwire/cadence_master.c | 39 ++++++++++++++++++++++++++-- drivers/soundwire/cadence_master.h | 5 ++++ drivers/soundwire/intel.h | 2 ++ drivers/soundwire/intel_auxdevice.c | 1 + drivers/soundwire/intel_bus_common.c | 11 ++++++++ 5 files changed, 56 insertions(+), 2 deletions(-) diff --git a/drivers/soundwire/cadence_master.c b/drivers/soundwire/cadence_master.c index e0683a5975d1..05652e983539 100644 --- a/drivers/soundwire/cadence_master.c +++ b/drivers/soundwire/cadence_master.c @@ -890,8 +890,14 @@ static int cdns_update_slave_status(struct sdw_cdns *cdns, } } - if (is_slave) - return sdw_handle_slave_status(&cdns->bus, status); + if (is_slave) { + int ret; + + mutex_lock(&cdns->status_update_lock); + ret = sdw_handle_slave_status(&cdns->bus, status); + mutex_unlock(&cdns->status_update_lock); + return ret; + } return 0; } @@ -988,6 +994,31 @@ irqreturn_t sdw_cdns_irq(int irq, void *dev_id) } EXPORT_SYMBOL(sdw_cdns_irq); +static void cdns_check_attached_status_dwork(struct work_struct *work) +{ + struct sdw_cdns *cdns = + container_of(work, struct sdw_cdns, attach_dwork.work); + enum sdw_slave_status status[SDW_MAX_DEVICES + 1]; + u32 val; + int ret; + int i; + + val = cdns_readl(cdns, CDNS_MCP_SLAVE_STAT); + + for (i = 0; i <= SDW_MAX_DEVICES; i++) { + status[i] = val & 0x3; + if (status[i]) + dev_dbg(cdns->dev, "Peripheral %d status: %d\n", i, status[i]); + val >>= 2; + } + + mutex_lock(&cdns->status_update_lock); + ret = sdw_handle_slave_status(&cdns->bus, status); + mutex_unlock(&cdns->status_update_lock); + if (ret < 0) + dev_err(cdns->dev, "%s: sdw_handle_slave_status failed: %d\n", __func__, ret); +} + /** * cdns_update_slave_status_work - update slave status in a work since we will need to handle * other interrupts eg. CDNS_MCP_INT_RX_WL during the update slave @@ -1740,7 +1771,11 @@ int sdw_cdns_probe(struct sdw_cdns *cdns) init_completion(&cdns->tx_complete); cdns->bus.port_ops = &cdns_port_ops; + mutex_init(&cdns->status_update_lock); + INIT_WORK(&cdns->work, cdns_update_slave_status_work); + INIT_DELAYED_WORK(&cdns->attach_dwork, cdns_check_attached_status_dwork); + return 0; } EXPORT_SYMBOL(sdw_cdns_probe); diff --git a/drivers/soundwire/cadence_master.h b/drivers/soundwire/cadence_master.h index bc84435e420f..e1d7969ba48a 100644 --- a/drivers/soundwire/cadence_master.h +++ b/drivers/soundwire/cadence_master.h @@ -117,6 +117,8 @@ struct sdw_cdns_dai_runtime { * @link_up: Link status * @msg_count: Messages sent on bus * @dai_runtime_array: runtime context for each allocated DAI. + * @status_update_lock: protect concurrency between interrupt-based and delayed work + * status update */ struct sdw_cdns { struct device *dev; @@ -148,10 +150,13 @@ struct sdw_cdns { bool interrupt_enabled; struct work_struct work; + struct delayed_work attach_dwork; struct list_head list; struct sdw_cdns_dai_runtime **dai_runtime_array; + + struct mutex status_update_lock; /* add mutual exclusion to sdw_handle_slave_status() */ }; #define bus_to_cdns(_bus) container_of(_bus, struct sdw_cdns, bus) diff --git a/drivers/soundwire/intel.h b/drivers/soundwire/intel.h index 68838e843b54..f4235f5991c3 100644 --- a/drivers/soundwire/intel.h +++ b/drivers/soundwire/intel.h @@ -103,6 +103,8 @@ static inline void intel_writew(void __iomem *base, int offset, u16 value) #define INTEL_MASTER_RESET_ITERATIONS 10 +#define SDW_INTEL_DELAYED_ENUMERATION_MS 100 + #define SDW_INTEL_CHECK_OPS(sdw, cb) ((sdw) && (sdw)->link_res && (sdw)->link_res->hw_ops && \ (sdw)->link_res->hw_ops->cb) #define SDW_INTEL_OPS(sdw, cb) ((sdw)->link_res->hw_ops->cb) diff --git a/drivers/soundwire/intel_auxdevice.c b/drivers/soundwire/intel_auxdevice.c index 8807e01cbf7c..dff49c5ce5b3 100644 --- a/drivers/soundwire/intel_auxdevice.c +++ b/drivers/soundwire/intel_auxdevice.c @@ -475,6 +475,7 @@ static void intel_link_remove(struct auxiliary_device *auxdev) */ 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); diff --git a/drivers/soundwire/intel_bus_common.c b/drivers/soundwire/intel_bus_common.c index df944e11b9ca..2bc960d05780 100644 --- a/drivers/soundwire/intel_bus_common.c +++ b/drivers/soundwire/intel_bus_common.c @@ -60,6 +60,9 @@ int intel_start_bus(struct sdw_intel *sdw) sdw_cdns_check_self_clearing_bits(cdns, __func__, true, INTEL_MASTER_RESET_ITERATIONS); + schedule_delayed_work(&cdns->attach_dwork, + msecs_to_jiffies(SDW_INTEL_DELAYED_ENUMERATION_MS)); + return 0; } @@ -151,6 +154,9 @@ int intel_start_bus_after_reset(struct sdw_intel *sdw) } sdw_cdns_check_self_clearing_bits(cdns, __func__, true, INTEL_MASTER_RESET_ITERATIONS); + schedule_delayed_work(&cdns->attach_dwork, + msecs_to_jiffies(SDW_INTEL_DELAYED_ENUMERATION_MS)); + return 0; } @@ -184,6 +190,9 @@ int intel_start_bus_after_clock_stop(struct sdw_intel *sdw) sdw_cdns_check_self_clearing_bits(cdns, __func__, true, INTEL_MASTER_RESET_ITERATIONS); + schedule_delayed_work(&cdns->attach_dwork, + msecs_to_jiffies(SDW_INTEL_DELAYED_ENUMERATION_MS)); + return 0; } @@ -194,6 +203,8 @@ int intel_stop_bus(struct sdw_intel *sdw, bool clock_stop) bool wake_enable = false; int ret; + cancel_delayed_work_sync(&cdns->attach_dwork); + if (clock_stop) { ret = sdw_cdns_clock_stop(cdns, true); if (ret < 0) From 5aedb8d8336b0a0421b58ca27d1b572aa6695b5b Mon Sep 17 00:00:00 2001 From: Pierre-Louis Bossart Date: Mon, 5 Aug 2024 19:50:03 +0800 Subject: [PATCH 5/5] soundwire: intel_bus_common: enable interrupts before exiting reset The existing code enables the Cadence IP interrupts after the bus reset sequence. The problem with this sequence is that it might be pre-empted, giving SoundWire devices time to sync and report as ATTACHED before the interrupts are enabled. In that case, the Cadence IP will not detect a state change and will not throw an interrupt to proceed with the enumeration of a Device0. In our overnight stress tests, we observed that a slight sub-millisecond delay in enabling interrupts after the reset was correlated with detection failures. This problem is more prevalent on the LunarLake silicon, likely due to SOC integration changes, but it was observed on earlier generations as well. This patch reverts the sequence, with the interrupts enabled before performing the bus reset. This removes the race condition and makes sure the Cadence IP is able to detect the presence of a Device0 in all cases. Signed-off-by: Pierre-Louis Bossart Signed-off-by: Bard Liao Link: https://lore.kernel.org/r/20240805115003.88035-1-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul --- drivers/soundwire/intel_bus_common.c | 24 ++++++++++++------------ 1 file changed, 12 insertions(+), 12 deletions(-) diff --git a/drivers/soundwire/intel_bus_common.c b/drivers/soundwire/intel_bus_common.c index 2bc960d05780..d3ff6c65b64c 100644 --- a/drivers/soundwire/intel_bus_common.c +++ b/drivers/soundwire/intel_bus_common.c @@ -45,18 +45,18 @@ int intel_start_bus(struct sdw_intel *sdw) return ret; } - ret = sdw_cdns_exit_reset(cdns); - if (ret < 0) { - dev_err(dev, "%s: unable to exit bus reset sequence: %d\n", __func__, ret); - return ret; - } - ret = sdw_cdns_enable_interrupt(cdns, true); if (ret < 0) { dev_err(dev, "%s: cannot enable interrupts: %d\n", __func__, ret); return ret; } + ret = sdw_cdns_exit_reset(cdns); + if (ret < 0) { + dev_err(dev, "%s: unable to exit bus reset sequence: %d\n", __func__, ret); + return ret; + } + sdw_cdns_check_self_clearing_bits(cdns, __func__, true, INTEL_MASTER_RESET_ITERATIONS); @@ -139,18 +139,18 @@ int intel_start_bus_after_reset(struct sdw_intel *sdw) 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; - } - 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; + } + } sdw_cdns_check_self_clearing_bits(cdns, __func__, true, INTEL_MASTER_RESET_ITERATIONS);