kernel/linux.git/drivers/soundwire/bus.c, branch v5.15.208

soundwire: fix enumeration completion

2023-08-11T13:14:00+00:00

[ Upstream commit c40d6b3249b11d60e09d81530588f56233d9aa44 ] The soundwire subsystem uses two completion structures that allow drivers to wait for soundwire device to become enumerated on the bus and initialised by their drivers, respectively. The code implementing the signalling is currently broken as it does not signal all current and future waiters and also uses the wrong reinitialisation function, which can potentially lead to memory corruption if there are still waiters on the queue. Not signalling future waiters specifically breaks sound card probe deferrals as codec drivers can not tell that the soundwire device is already attached when being reprobed. Some codec runtime PM implementations suffer from similar problems as waiting for enumeration during resume can also timeout despite the device already having been enumerated. Fixes: fb9469e54fa7 ("soundwire: bus: fix race condition with enumeration_complete signaling") Fixes: a90def068127 ("soundwire: bus: fix race condition with initialization_complete signaling") Cc: stable@vger.kernel.org # 5.7 Cc: Pierre-Louis Bossart Cc: Rander Wang Signed-off-by: Johan Hovold Reviewed-by: Pierre-Louis Bossart Link: https://lore.kernel.org/r/20230705123018.30903-2-johan+linaro@kernel.org Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin

soundwire: bus: pm_runtime_request_resume on peripheral attachment

2023-08-11T13:14:00+00:00

[ Upstream commit e557bca49b812908f380c56b5b4b2f273848b676 ] In typical use cases, the peripheral becomes pm_runtime active as a result of the ALSA/ASoC framework starting up a DAI. The parent/child hierarchy guarantees that the manager device will be fully resumed beforehand. There is however a corner case where the manager device may become pm_runtime active, but without ALSA/ASoC requesting any functionality from the peripherals. In this case, the hardware peripheral device will report as ATTACHED and its initialization routine will be executed. If this initialization routine initiates any sort of deferred processing, there is a possibility that the manager could suspend without the peripheral suspend sequence being invoked: from the pm_runtime framework perspective, the peripheral is *already* suspended. To avoid such disconnects between hardware state and pm_runtime state, this patch adds an asynchronous pm_request_resume() upon successful attach/initialization which will result in the proper resume/suspend sequence to be followed on the peripheral side. BugLink: https://github.com/thesofproject/linux/issues/3459 Signed-off-by: Pierre-Louis Bossart Reviewed-by: Ranjani Sridharan Reviewed-by: Rander Wang Signed-off-by: Bard Liao Link: https://lore.kernel.org/r/20220420023241.14335-4-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul Stable-dep-of: c40d6b3249b1 ("soundwire: fix enumeration completion") Signed-off-by: Sasha Levin

soundwire: revisit driver bind/unbind and callbacks

2022-08-17T12:23:48+00:00

[ Upstream commit bd29c00edd0a5dac8b6e7332bb470cd50f92e893 ] In the SoundWire probe, we store a pointer from the driver ops into the 'slave' structure. This can lead to kernel oopses when unbinding codec drivers, e.g. with the following sequence to remove machine driver and codec driver. /sbin/modprobe -r snd_soc_sof_sdw /sbin/modprobe -r snd_soc_rt711 The full details can be found in the BugLink below, for reference the two following examples show different cases of driver ops/callbacks being invoked after the driver .remove(). kernel: BUG: kernel NULL pointer dereference, address: 0000000000000150 kernel: Workqueue: events cdns_update_slave_status_work [soundwire_cadence] kernel: RIP: 0010:mutex_lock+0x19/0x30 kernel: Call Trace: kernel: ? sdw_handle_slave_status+0x426/0xe00 [soundwire_bus 94ff184bf398570c3f8ff7efe9e32529f532e4ae] kernel: ? newidle_balance+0x26a/0x400 kernel: ? cdns_update_slave_status_work+0x1e9/0x200 [soundwire_cadence 1bcf98eebe5ba9833cd433323769ac923c9c6f82] kernel: BUG: unable to handle page fault for address: ffffffffc07654c8 kernel: Workqueue: pm pm_runtime_work kernel: RIP: 0010:sdw_bus_prep_clk_stop+0x6f/0x160 [soundwire_bus] kernel: Call Trace: kernel: kernel: sdw_cdns_clock_stop+0xb5/0x1b0 [soundwire_cadence 1bcf98eebe5ba9833cd433323769ac923c9c6f82] kernel: intel_suspend_runtime+0x5f/0x120 [soundwire_intel aca858f7c87048d3152a4a41bb68abb9b663a1dd] kernel: ? dpm_sysfs_remove+0x60/0x60 This was not detected earlier in Intel tests since the tests first remove the parent PCI device and shut down the bus. The sequence above is a corner case which keeps the bus operational but without a driver bound. While trying to solve this kernel oopses, it became clear that the existing SoundWire bus does not deal well with the unbind case. Commit 528be501b7d4a ("soundwire: sdw_slave: add probe_complete structure and new fields") added a 'probed' status variable and a 'probe_complete' struct completion. This status is however not reset on remove and likewise the 'probe complete' is not re-initialized, so the bind/unbind/bind test cases would fail. The timeout used before the 'update_status' callback was also a bad idea in hindsight, there should really be no timing assumption as to if and when a driver is bound to a device. An initial draft was based on device_lock() and device_unlock() was tested. This proved too complicated, with deadlocks created during the suspend-resume sequences, which also use the same device_lock/unlock() as the bind/unbind sequences. On a CometLake device, a bad DSDT/BIOS caused spurious resumes and the use of device_lock() caused hangs during suspend. After multiple weeks or testing and painful reverse-engineering of deadlocks on different devices, we looked for alternatives that did not interfere with the device core. A bus notifier was used successfully to keep track of DRIVER_BOUND and DRIVER_UNBIND events. This solved the bind-unbind-bind case in tests, but it can still be defeated with a theoretical corner case where the memory is freed by a .remove while the callback is in use. The notifier only helps make sure the driver callbacks are valid, but not that the memory allocated in probe remains valid while the callbacks are invoked. This patch suggests the introduction of a new 'sdw_dev_lock' mutex protecting probe/remove and all driver callbacks. Since this mutex is 'local' to SoundWire only, it does not interfere with existing locks and does not create deadlocks. In addition, this patch removes the 'probe_complete' completion, instead we directly invoke the 'update_status' from the probe routine. That removes any sort of timing dependency and a much better support for the device/driver model, the driver could be bound before the bus started, or eons after the bus started and the hardware would be properly initialized in all cases. BugLink: https://github.com/thesofproject/linux/issues/3531 Fixes: 56d4fe31af77 ("soundwire: Add MIPI DisCo property helpers") Fixes: 528be501b7d4a ("soundwire: sdw_slave: add probe_complete structure and new fields") Signed-off-by: Pierre-Louis Bossart Reviewed-by: Rander Wang Reviewed-by: Ranjani Sridharan Reviewed-by: Bard Liao Reviewed-by: Péter Ujfalusi Link: https://lore.kernel.org/r/20220621225641.221170-2-pierre-louis.bossart@linux.intel.com Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin

soundwire: bus: stop dereferencing invalid slave pointer

2021-11-18T18:16:54+00:00

[ Upstream commit 4cbbe74d906be0bcffbe1e74b43a00f99626a69c ] Slave pointer is invalid after end of list iteration, using this would result in below Memory abort. Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004 ... Call trace: __dev_printk+0x34/0x7c _dev_warn+0x6c/0x90 sdw_bus_exit_clk_stop+0x194/0x1d0 swrm_runtime_resume+0x13c/0x238 pm_generic_runtime_resume+0x2c/0x48 __rpm_callback+0x44/0x150 rpm_callback+0x6c/0x78 rpm_resume+0x314/0x558 rpm_resume+0x378/0x558 rpm_resume+0x378/0x558 __pm_runtime_resume+0x3c/0x88 Use bus->dev instead to print this error message. Fixes: b50bb8ba369cd ("soundwire: bus: handle -ENODATA errors in clock stop/start sequences") Signed-off-by: Srinivas Kandagatla Reviewed-by: Pierre-Louis Bossart Link: https://lore.kernel.org/r/20211012101521.32087-1-srinivas.kandagatla@linaro.org Signed-off-by: Vinod Koul Signed-off-by: Sasha Levin

soundwire: bus: squelch error returned by mockup devices

2021-08-02T05:38:22+00:00

All read and writes from/to SoundWire mockup devices will return -ENODATA/Command_Ignored, this patch forces a Command_OK result to let the bus perform the required configurations, e.g. for the Data Ports, which will only have an effect on the Master side. Signed-off-by: Pierre-Louis Bossart Reviewed-by: Rander Wang Signed-off-by: Bard Liao Link: https://lore.kernel.org/r/20210714032209.11284-8-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul

soundwire: bus: update Slave status in sdw_clear_slave_status

2021-07-22T14:25:37+00:00

Call to sdw_update_slave_status() needs to be added to sdw_clear_slave_ status() to ensure Slaves are informed of the new status via update_ status() callback. This will enable codec drivers to reset their internal states and make sure the register settings are properly restored on pm_runtime or system resume BugLink: https://github.com/thesofproject/linux/issues/2908 BugLink: https://github.com/thesofproject/linux/issues/2637 Signed-off-by: Bard Liao Reviewed-by: Guennadi Liakhovetski Link: https://lore.kernel.org/r/20210714033609.11963-1-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul

soundwire: bus: filter out more -EDATA errors on clock stop

2021-07-22T14:16:54+00:00

We've added quite a few filters to avoid throwing errors if a Device does not respond to commands during the clock stop sequences, but we missed one. This will lead to an isolated message [ 6115.294412] soundwire sdw-master-1: SDW_SCP_STAT bread failed:-61 The callers already filter this error code, so there's no point in keeping it at the lower level. Since this is a recoverable error, make this dev_err() conditional and only log cases with Command Failed. Signed-off-by: Pierre-Louis Bossart Reviewed-by: Guennadi Liakhovetski Signed-off-by: Bard Liao Link: https://lore.kernel.org/r/20210714014209.17357-1-yung-chuan.liao@linux.intel.com Signed-off-by: Vinod Koul

Merge tag 'char-misc-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc

2021-07-05T20:42:16+00:00

Pull char / misc driver updates from Greg KH: "Here is the big set of char / misc and other driver subsystem updates for 5.14-rc1. Included in here are: - habanalabs driver updates - fsl-mc driver updates - comedi driver updates - fpga driver updates - extcon driver updates - interconnect driver updates - mei driver updates - nvmem driver updates - phy driver updates - pnp driver updates - soundwire driver updates - lots of other tiny driver updates for char and misc drivers This is looking more and more like the "various driver subsystems mushed together" tree... All of these have been in linux-next for a while with no reported issues" * tag 'char-misc-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (292 commits) mcb: Use DEFINE_RES_MEM() helper macro and fix the end address PNP: moved EXPORT_SYMBOL so that it immediately followed its function/variable bus: mhi: pci-generic: Add missing 'pci_disable_pcie_error_reporting()' calls bus: mhi: Wait for M2 state during system resume bus: mhi: core: Fix power down latency intel_th: Wait until port is in reset before programming it intel_th: msu: Make contiguous buffers uncached intel_th: Remove an unused exit point from intel_th_remove() stm class: Spelling fix nitro_enclaves: Set Bus Master for the NE PCI device misc: ibmasm: Modify matricies to matrices misc: vmw_vmci: return the correct errno code siox: Simplify error handling via dev_err_probe() fpga: machxo2-spi: Address warning about unused variable lkdtm/heap: Add init_on_alloc tests selftests/lkdtm: Enable various testable CONFIGs lkdtm: Add CONFIG hints in errors where possible lkdtm: Enable DOUBLE_FAULT on all architectures lkdtm/heap: Add vmalloc linear overflow test lkdtm/bugs: XFAIL UNALIGNED_LOAD_STORE_WRITE ...

soundwire: export sdw_update() and sdw_update_no_pm()

2021-06-21T12:00:42+00:00

We currently export sdw_read() and sdw_write() but the sdw_update() and sdw_update_no_pm() are currently available only to the bus code. This was missed in an earlier contribution. Export both functions so that codec drivers can perform read-modify-write operations without duplicating the code. Fixes: b04c975e654c ('soundwire: bus: use sdw_update_no_pm when initializing a device') Signed-off-by: Pierre-Louis Bossart Reviewed-by: Bard Liao Reviewed-by: Péter Ujfalusi Acked-By: Vinod Koul Link: https://lore.kernel.org/r/20210614180815.153711-2-pierre-louis.bossart@linux.intel.com Signed-off-by: Mark Brown

soundwire: bus: Make sdw_nwrite() data pointer argument const

2021-06-20T11:16:14+00:00

Idiomatically, write functions should take const pointers to the data buffer, as they don't change the data. They are also likely to be called from functions that receive a const data pointer. Internally the pointer is passed to function/structs shared with the read functions, requiring a cast, but this is an implementation detail that should be hidden by the public API. Signed-off-by: Richard Fitzgerald Link: https://lore.kernel.org/r/20210616145901.29402-1-rf@opensource.cirrus.com Signed-off-by: Vinod Koul