From: Loic Poulain loic.poulain@linaro.org
For whatever reason, some devices like QCA6390, WCN6855 using ath11k are not in M3 state during PM resume, but still functional. The mhi_pm_resume should then not fail in those cases, and let the higher level device specific stack continue resuming process.
Add a new parameter to mhi_pm_resume, to force resuming, whatever the current MHI state is. This fixes a regression with non functional ath11k WiFi after suspend/resume cycle on some machines.
Bug report: https://bugzilla.kernel.org/show_bug.cgi?id=214179
Cc: stable@vger.kernel.org #5.13 Fixes: 020d3b26c07a ("bus: mhi: Early MHI resume failure in non M3 state") Reported-by: Kalle Valo kvalo@codeaurora.org Reported-by: Pengyu Ma mapengyu@gmail.com Signed-off-by: Loic Poulain loic.poulain@linaro.org [mani: Added comment, bug report, added reported-by tags and CCed stable] Signed-off-by: Manivannan Sadhasivam manivannan.sadhasivam@linaro.org --- drivers/bus/mhi/core/pm.c | 10 +++++++--- drivers/bus/mhi/pci_generic.c | 2 +- drivers/net/wireless/ath/ath11k/mhi.c | 6 +++++- include/linux/mhi.h | 3 ++- 4 files changed, 15 insertions(+), 6 deletions(-)
diff --git a/drivers/bus/mhi/core/pm.c b/drivers/bus/mhi/core/pm.c index 7464f5d09973..4ddd266e042e 100644 --- a/drivers/bus/mhi/core/pm.c +++ b/drivers/bus/mhi/core/pm.c @@ -881,7 +881,7 @@ int mhi_pm_suspend(struct mhi_controller *mhi_cntrl) } EXPORT_SYMBOL_GPL(mhi_pm_suspend);
-int mhi_pm_resume(struct mhi_controller *mhi_cntrl) +int mhi_pm_resume(struct mhi_controller *mhi_cntrl, bool force) { struct mhi_chan *itr, *tmp; struct device *dev = &mhi_cntrl->mhi_dev->dev; @@ -898,8 +898,12 @@ int mhi_pm_resume(struct mhi_controller *mhi_cntrl) if (MHI_PM_IN_ERROR_STATE(mhi_cntrl->pm_state)) return -EIO;
- if (mhi_get_mhi_state(mhi_cntrl) != MHI_STATE_M3) - return -EINVAL; + if (mhi_get_mhi_state(mhi_cntrl) != MHI_STATE_M3) { + dev_warn(dev, "Resuming from non M3 state (%s)\n", + TO_MHI_STATE_STR(mhi_get_mhi_state(mhi_cntrl))); + if (!force) + return -EINVAL; + }
/* Notify clients about exiting LPM */ list_for_each_entry_safe(itr, tmp, &mhi_cntrl->lpm_chans, node) { diff --git a/drivers/bus/mhi/pci_generic.c b/drivers/bus/mhi/pci_generic.c index 9ef41354237c..efd1da66fdf9 100644 --- a/drivers/bus/mhi/pci_generic.c +++ b/drivers/bus/mhi/pci_generic.c @@ -959,7 +959,7 @@ static int __maybe_unused mhi_pci_runtime_resume(struct device *dev) return 0; /* Nothing to do at MHI level */
/* Exit M3, transition to M0 state */ - err = mhi_pm_resume(mhi_cntrl); + err = mhi_pm_resume(mhi_cntrl, false); if (err) { dev_err(&pdev->dev, "failed to resume device: %d\n", err); goto err_recovery; diff --git a/drivers/net/wireless/ath/ath11k/mhi.c b/drivers/net/wireless/ath/ath11k/mhi.c index 26c7ae242db6..f1f2fa2d690d 100644 --- a/drivers/net/wireless/ath/ath11k/mhi.c +++ b/drivers/net/wireless/ath/ath11k/mhi.c @@ -533,7 +533,11 @@ static int ath11k_mhi_set_state(struct ath11k_pci *ab_pci, ret = mhi_pm_suspend(ab_pci->mhi_ctrl); break; case ATH11K_MHI_RESUME: - ret = mhi_pm_resume(ab_pci->mhi_ctrl); + /* Do force MHI resume as some devices like QCA6390, WCN6855 + * are not in M3 state but they are functional. So just ignore + * the MHI state while resuming. + */ + ret = mhi_pm_resume(ab_pci->mhi_ctrl, true); break; case ATH11K_MHI_TRIGGER_RDDM: ret = mhi_force_rddm_mode(ab_pci->mhi_ctrl); diff --git a/include/linux/mhi.h b/include/linux/mhi.h index 723985879035..102303288cee 100644 --- a/include/linux/mhi.h +++ b/include/linux/mhi.h @@ -660,8 +660,9 @@ int mhi_pm_suspend(struct mhi_controller *mhi_cntrl); /** * mhi_pm_resume - Resume MHI from suspended state * @mhi_cntrl: MHI controller + * @force: Force resuming to M0 irrespective of the device MHI state */ -int mhi_pm_resume(struct mhi_controller *mhi_cntrl); +int mhi_pm_resume(struct mhi_controller *mhi_cntrl, bool force);
/** * mhi_download_rddm_image - Download ramdump image from device for