Baochen Qiang <quic_bqiang@xxxxxxxxxxx> writes: > On 2/29/2024 6:12 PM, Manivannan Sadhasivam wrote: >> On Wed, Feb 28, 2024 at 10:22:41AM +0800, Baochen Qiang wrote: >>> ath11k fails to resume: >>> >>> ath11k_pci 0000:06:00.0: timeout while waiting for restart complete >>> >>> This happens because when calling mhi_sync_power_up() the MHI subsystem >>> eventually calls device_add() from mhi_create_devices() but the device >>> creation is deferred: >>> >>> mhi mhi0_IPCR: Driver qcom_mhi_qrtr force probe deferral >>> >>> The reason for deferring device creation is explained in dpm_prepare(): >>> >>> /* >>> * It is unsafe if probing of devices will happen during suspend or >>> * hibernation and system behavior will be unpredictable in this case. >>> * So, let's prohibit device's probing here and defer their probes >>> * instead. The normal behavior will be restored in dpm_complete(). >>> */ >>> >>> Because the device probe is deferred, the qcom_mhi_qrtr_probe() is not >>> called and thus MHI channels are not prepared: >>> >>> So what this means that QRTR is not delivering messages and the QMI connection >>> is not working between ath11k and the firmware, resulting a failure in firmware >>> initialization. >>> >>> To fix this add new function mhi_power_down_keep_dev() which doesn't destroy >>> the devices for channels during power down. This way we avoid probe defer issue >>> and finally can get ath11k hibernation working with the following patches. >>> >>> Tested-on: WCN6855 hw2.0 PCI WLAN.HSP.1.1-03125-QCAHSPSWPL_V1_V2_SILICONZ_LITE-3.6510.30 >>> >>> Signed-off-by: Kalle Valo <quic_kvalo@xxxxxxxxxxx> >> >> Did Kalle co-author this patch? If so, his Co-developed-by tag should >> be added. > > Hmm, I'm not sure... I would like Kalle's thoughts on this. IIRC I did only some simple cleanup before submitting the patch so I don't think Co-developed-by is justified. I'm also fine with removing my Signed-off-by. -- https://patchwork.kernel.org/project/linux-wireless/list/ https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
