On 16/03/20 8:47 pm, Hans de Goede wrote: > Based on a sample of 7 DSDTs from Cherry Trail devices using an AXP288 > PMIC depending on the design one of 2 possible LDOs on the PMIC is used > for the MMC signalling voltage, either DLDO3 or GPIO1LDO (GPIO1 pin in > low noise LDO mode). > > The Lenovo Miix 320-10ICR uses GPIO1LDO in the SHC1 ACPI device's DSM > methods to set 3.3 or 1.8 signalling voltage and this appears to work > as advertised, so presumably the device is actually using GPIO1LDO for > the external microSD signalling voltage. > > But this device has a bug in the _PS0 method of the SHC1 ACPI device, > the DSM remembers the last set signalling voltage and the _PS0 restores > this after a (runtime) suspend-resume cycle, but it "restores" the voltage > on DLDO3 instead of setting it on GPIO1LDO as the DSM method does. DLDO3 > is used for the LCD and setting it to 1.8V causes the LCD to go black. > > This commit works around this issue by calling the Intel DSM to reset the > signal voltage to 3.3V after the host has been runtime suspended. > This will make the _PS0 method reprogram the DLDO3 voltage to 3.3V, which > leaves it at its original setting fixing the LCD going black. > > This commit adds and uses a DMI quirk mechanism to only trigger this > workaround on the Lenovo Miix 320 while leaving the behavior of the > driver unchanged on other devices. > > BugLink: https://bugs.freedesktop.org/show_bug.cgi?id=111294 > BugLink: https://gitlab.freedesktop.org/drm/intel/issues/355 > Reported-by: russianneuromancer <russianneuromancer@xxxxx> > Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx> Acked-by: Adrian Hunter <adrian.hunter@xxxxxxxxx> > --- > Changes in v3: > - Drop code to restore 1.8 signal voltage on suspend, this is not necessary > - Add an is_intel bool to sdhci_acpi_host instead of checking for: > mmc_host_ops.start_signal_voltage_switch == intel_start_signal_voltage_switch > > Changes in v2: > - Make the quirk reset the signal voltage to 3.3V at the end of the > (runtime) suspend handler instead of disabling 1.8V modes > - Drop the module option to allow overridig the quirks > --- > drivers/mmc/host/sdhci-acpi.c | 68 +++++++++++++++++++++++++++++++++-- > 1 file changed, 66 insertions(+), 2 deletions(-) > > diff --git a/drivers/mmc/host/sdhci-acpi.c b/drivers/mmc/host/sdhci-acpi.c > index 9651dca6863e..b4c1b2367066 100644 > --- a/drivers/mmc/host/sdhci-acpi.c > +++ b/drivers/mmc/host/sdhci-acpi.c > @@ -23,6 +23,7 @@ > #include <linux/pm.h> > #include <linux/pm_runtime.h> > #include <linux/delay.h> > +#include <linux/dmi.h> > > #include <linux/mmc/host.h> > #include <linux/mmc/pm.h> > @@ -72,9 +73,15 @@ struct sdhci_acpi_host { > const struct sdhci_acpi_slot *slot; > struct platform_device *pdev; > bool use_runtime_pm; > + bool is_intel; > + bool reset_signal_volt_on_suspend; > unsigned long private[0] ____cacheline_aligned; > }; > > +enum { > + DMI_QUIRK_RESET_SD_SIGNAL_VOLT_ON_SUSP = BIT(0), > +}; > + > static inline void *sdhci_acpi_priv(struct sdhci_acpi_host *c) > { > return (void *)c->private; > @@ -391,6 +398,8 @@ static int intel_probe_slot(struct platform_device *pdev, struct acpi_device *ad > host->mmc_host_ops.start_signal_voltage_switch = > intel_start_signal_voltage_switch; > > + c->is_intel = true; > + > return 0; > } > > @@ -647,6 +656,24 @@ static const struct acpi_device_id sdhci_acpi_ids[] = { > }; > MODULE_DEVICE_TABLE(acpi, sdhci_acpi_ids); > > +static const struct dmi_system_id sdhci_acpi_quirks[] = { > + { > + /* > + * The Lenovo Miix 320-10ICR has a bug in the _PS0 method of > + * the SHC1 ACPI device, this bug causes it to reprogram the > + * wrong LDO (DLDO3) to 1.8V if 1.8V modes are used and the > + * card is (runtime) suspended + resumed. DLDO3 is used for > + * the LCD and setting it to 1.8V causes the LCD to go black. > + */ > + .matches = { > + DMI_MATCH(DMI_SYS_VENDOR, "LENOVO"), > + DMI_MATCH(DMI_PRODUCT_VERSION, "Lenovo MIIX 320-10ICR"), > + }, > + .driver_data = (void *)DMI_QUIRK_RESET_SD_SIGNAL_VOLT_ON_SUSP, > + }, > + {} /* Terminating entry */ > +}; > + > static const struct sdhci_acpi_slot *sdhci_acpi_get_slot(struct acpi_device *adev) > { > const struct sdhci_acpi_uid_slot *u; > @@ -663,17 +690,23 @@ static int sdhci_acpi_probe(struct platform_device *pdev) > struct device *dev = &pdev->dev; > const struct sdhci_acpi_slot *slot; > struct acpi_device *device, *child; > + const struct dmi_system_id *id; > struct sdhci_acpi_host *c; > struct sdhci_host *host; > struct resource *iomem; > resource_size_t len; > size_t priv_size; > + int quirks = 0; > int err; > > device = ACPI_COMPANION(dev); > if (!device) > return -ENODEV; > > + id = dmi_first_match(sdhci_acpi_quirks); > + if (id) > + quirks = (long)id->driver_data; > + > slot = sdhci_acpi_get_slot(device); > > /* Power on the SDHCI controller and its children */ > @@ -759,6 +792,9 @@ static int sdhci_acpi_probe(struct platform_device *pdev) > dev_warn(dev, "failed to setup card detect gpio\n"); > c->use_runtime_pm = false; > } > + > + if (quirks & DMI_QUIRK_RESET_SD_SIGNAL_VOLT_ON_SUSP) > + c->reset_signal_volt_on_suspend = true; > } > > err = sdhci_setup_host(host); > @@ -823,17 +859,39 @@ static int sdhci_acpi_remove(struct platform_device *pdev) > return 0; > } > > +static void __maybe_unused sdhci_acpi_reset_signal_voltage_if_needed( > + struct device *dev) > +{ > + struct sdhci_acpi_host *c = dev_get_drvdata(dev); > + struct sdhci_host *host = c->host; > + > + if (c->is_intel && c->reset_signal_volt_on_suspend && > + host->mmc->ios.signal_voltage != MMC_SIGNAL_VOLTAGE_330) { > + struct intel_host *intel_host = sdhci_acpi_priv(c); > + unsigned int fn = INTEL_DSM_V33_SWITCH; > + u32 result = 0; > + > + intel_dsm(intel_host, dev, fn, &result); > + } > +} > + > #ifdef CONFIG_PM_SLEEP > > static int sdhci_acpi_suspend(struct device *dev) > { > struct sdhci_acpi_host *c = dev_get_drvdata(dev); > struct sdhci_host *host = c->host; > + int ret; > > if (host->tuning_mode != SDHCI_TUNING_MODE_3) > mmc_retune_needed(host->mmc); > > - return sdhci_suspend_host(host); > + ret = sdhci_suspend_host(host); > + if (ret) > + return ret; > + > + sdhci_acpi_reset_signal_voltage_if_needed(dev); > + return 0; > } > > static int sdhci_acpi_resume(struct device *dev) > @@ -853,11 +911,17 @@ static int sdhci_acpi_runtime_suspend(struct device *dev) > { > struct sdhci_acpi_host *c = dev_get_drvdata(dev); > struct sdhci_host *host = c->host; > + int ret; > > if (host->tuning_mode != SDHCI_TUNING_MODE_3) > mmc_retune_needed(host->mmc); > > - return sdhci_runtime_suspend_host(host); > + ret = sdhci_runtime_suspend_host(host); > + if (ret) > + return ret; > + > + sdhci_acpi_reset_signal_voltage_if_needed(dev); > + return 0; > } > > static int sdhci_acpi_runtime_resume(struct device *dev) >
