6.6-stable review patch. If anyone has any objections, please let me know.
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From: Adrian Hunter adrian.hunter@intel.com
commit bb44826c3bdbf1fa3957008a04908f45e5666463 upstream.
Intel platforms with UFS, can support Suspend-to-Idle (S0ix) and Suspend-to-RAM (S3). For S0ix the link state should be HIBERNATE. For S3, state is lost, so the link state must be OFF. Driver policy, expressed by spm_lvl, can be 3 (link HIBERNATE, device SLEEP) for S0ix but must be changed to 5 (link OFF, device POWEROFF) for S3.
Fix support for S0ix/S3 by switching spm_lvl as needed. During suspend ->prepare(), if the suspend target state is not Suspend-to-Idle, ensure the spm_lvl is at least 5 to ensure that resume will be possible from deep sleep states. During suspend ->complete(), restore the spm_lvl to its original value that is suitable for S0ix.
This fix is first needed in Intel Alder Lake based controllers.
Fixes: 7dc9fb47bc9a ("scsi: ufs: ufs-pci: Add support for Intel ADL") Cc: stable@vger.kernel.org Signed-off-by: Adrian Hunter adrian.hunter@intel.com Reviewed-by: Bart Van Assche bvanassche@acm.org Link: https://patch.msgid.link/20251024085918.31825-2-adrian.hunter@intel.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/ufs/host/ufshcd-pci.c | 67 ++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 65 insertions(+), 2 deletions(-)
--- a/drivers/ufs/host/ufshcd-pci.c +++ b/drivers/ufs/host/ufshcd-pci.c @@ -15,6 +15,7 @@ #include <linux/pci.h> #include <linux/pm_runtime.h> #include <linux/pm_qos.h> +#include <linux/suspend.h> #include <linux/debugfs.h> #include <linux/uuid.h> #include <linux/acpi.h> @@ -34,6 +35,7 @@ struct intel_host { u32 dsm_fns; u32 active_ltr; u32 idle_ltr; + int saved_spm_lvl; struct dentry *debugfs_root; struct gpio_desc *reset_gpio; }; @@ -375,6 +377,7 @@ static int ufs_intel_common_init(struct host = devm_kzalloc(hba->dev, sizeof(*host), GFP_KERNEL); if (!host) return -ENOMEM; + host->saved_spm_lvl = -1; ufshcd_set_variant(hba, host); intel_dsm_init(host, hba->dev); if (INTEL_DSM_SUPPORTED(host, RESET)) { @@ -542,6 +545,66 @@ static int ufshcd_pci_restore(struct dev
return ufshcd_system_resume(dev); } + +static int ufs_intel_suspend_prepare(struct device *dev) +{ + struct ufs_hba *hba = dev_get_drvdata(dev); + struct intel_host *host = ufshcd_get_variant(hba); + int err; + + /* + * Only s2idle (S0ix) retains link state. Force power-off + * (UFS_PM_LVL_5) for any other case. + */ + if (pm_suspend_target_state != PM_SUSPEND_TO_IDLE && hba->spm_lvl < UFS_PM_LVL_5) { + host->saved_spm_lvl = hba->spm_lvl; + hba->spm_lvl = UFS_PM_LVL_5; + } + + err = ufshcd_suspend_prepare(dev); + + if (err < 0 && host->saved_spm_lvl != -1) { + hba->spm_lvl = host->saved_spm_lvl; + host->saved_spm_lvl = -1; + } + + return err; +} + +static void ufs_intel_resume_complete(struct device *dev) +{ + struct ufs_hba *hba = dev_get_drvdata(dev); + struct intel_host *host = ufshcd_get_variant(hba); + + ufshcd_resume_complete(dev); + + if (host->saved_spm_lvl != -1) { + hba->spm_lvl = host->saved_spm_lvl; + host->saved_spm_lvl = -1; + } +} + +static int ufshcd_pci_suspend_prepare(struct device *dev) +{ + struct ufs_hba *hba = dev_get_drvdata(dev); + + if (!strcmp(hba->vops->name, "intel-pci")) + return ufs_intel_suspend_prepare(dev); + + return ufshcd_suspend_prepare(dev); +} + +static void ufshcd_pci_resume_complete(struct device *dev) +{ + struct ufs_hba *hba = dev_get_drvdata(dev); + + if (!strcmp(hba->vops->name, "intel-pci")) { + ufs_intel_resume_complete(dev); + return; + } + + ufshcd_resume_complete(dev); +} #endif
/** @@ -624,8 +687,8 @@ static const struct dev_pm_ops ufshcd_pc .thaw = ufshcd_system_resume, .poweroff = ufshcd_system_suspend, .restore = ufshcd_pci_restore, - .prepare = ufshcd_suspend_prepare, - .complete = ufshcd_resume_complete, + .prepare = ufshcd_pci_suspend_prepare, + .complete = ufshcd_pci_resume_complete, #endif };