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> --- 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) -- 2.25.1
