On Thu, Dec 30, 2021 at 3:17 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
>
> x86 ACPI boards which ship with only Android as their factory image usually
> declare a whole bunch of bogus I2C devs in their ACPI tables and sometimes
> there are issues with serdev devices on these boards too, e.g. the resource
> points to the wrong serdev_controller.
>
> Instantiating I2C / serdev devs for these bogus devs causes various issues,
> e.g. GPIO/IRQ resource conflicts because sometimes drivers do bind to them.
> The Android x86 kernel fork shipped on these devices has some special code
> to remove the bogus I2C clients (and serdevs are ignored completely).
>
> Introduce acpi_quirk_skip_i2c_client_enumeration() and
> acpi_quirk_skip_serdev_enumeration() helpers. Which can be used by the I2C/
> serdev code to skip instantiating any I2C or serdev devs on broken boards.
>
> These 2 helpers are added to drivers/acpi/x86/utils.c so that the DMI table
> can be shared between the I2C and serdev code.
>
> Note these boards typically do actually have I2C and serdev devices, just
> different ones then the ones described in their DSDT. The devices which
> are actually present are manually instantiated by the
> drivers/platform/x86/x86-android-tablets.c kernel module.
>
> The new helpers are only build if CONFIG_X86_ANDROID_TABLETS is enabled,
> otherwise they are empty stubs to not unnecessarily grow the kernel size.
>
> Signed-off-by: Hans de Goede <hdegoede@xxxxxxxxxx>
> ---
> Changes in v2:
> - Move the i2c_acpi_known_good_ids[] list and checking into this patch /
> into the new acpi_quirk_skip_i2c_client_enumeration() function
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
or please let me know if you want me to take this series.
Thanks!
> ---
> drivers/acpi/x86/utils.c | 111 +++++++++++++++++++++++++++++++++++++++
> include/acpi/acpi_bus.h | 16 ++++++
> 2 files changed, 127 insertions(+)
>
> diff --git a/drivers/acpi/x86/utils.c b/drivers/acpi/x86/utils.c
> index a2ae1ac41319..375a0911f06d 100644
> --- a/drivers/acpi/x86/utils.c
> +++ b/drivers/acpi/x86/utils.c
> @@ -10,6 +10,7 @@
>
> #include <linux/acpi.h>
> #include <linux/dmi.h>
> +#include <linux/platform_device.h>
> #include <asm/cpu_device_id.h>
> #include <asm/intel-family.h>
> #include "../internal.h"
> @@ -208,3 +209,113 @@ bool force_storage_d3(void)
> {
> return x86_match_cpu(storage_d3_cpu_ids);
> }
> +
> +#if IS_ENABLED(CONFIG_X86_ANDROID_TABLETS)
> +/*
> + * x86 ACPI boards which ship with only Android as their factory image usually
> + * declare a whole bunch of bogus I2C devices in their ACPI tables and sometimes
> + * there are issues with serdev devices on these boards too, e.g. the resource
> + * points to the wrong serdev_controller.
> + *
> + * Instantiating I2C / serdev devs for these bogus devs causes various issues,
> + * e.g. GPIO/IRQ resource conflicts because sometimes drivers do bind to them.
> + * The Android x86 kernel fork shipped on these devices has some special code
> + * to remove the bogus I2C clients (and AFAICT serdevs are ignored completely).
> + *
> + * The acpi_quirk_skip_*_enumeration() functions below are used by the I2C or
> + * serdev code to skip instantiating any I2C or serdev devs on broken boards.
> + *
> + * In case of I2C an exception is made for HIDs on the i2c_acpi_known_good_ids
> + * list. These are known to always be correct (and in case of the audio-codecs
> + * the drivers heavily rely on the codec being enumerated through ACPI).
> + *
> + * Note these boards typically do actually have I2C and serdev devices,
> + * just different ones then the ones described in their DSDT. The devices
> + * which are actually present are manually instantiated by the
> + * drivers/platform/x86/x86-android-tablets.c kernel module.
> + */
> +#define ACPI_QUIRK_SKIP_I2C_CLIENTS BIT(0)
> +#define ACPI_QUIRK_UART1_TTY_UART2_SKIP BIT(1)
> +
> +static const struct dmi_system_id acpi_skip_serial_bus_enumeration_ids[] = {
> + {
> + .matches = {
> + DMI_EXACT_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
> + DMI_EXACT_MATCH(DMI_PRODUCT_NAME, "ME176C"),
> + },
> + .driver_data = (void *)(ACPI_QUIRK_SKIP_I2C_CLIENTS |
> + ACPI_QUIRK_UART1_TTY_UART2_SKIP),
> + },
> + {
> + .matches = {
> + DMI_MATCH(DMI_SYS_VENDOR, "ASUSTeK COMPUTER INC."),
> + DMI_MATCH(DMI_PRODUCT_NAME, "TF103C"),
> + },
> + .driver_data = (void *)ACPI_QUIRK_SKIP_I2C_CLIENTS,
> + },
> + {
> + /* Whitelabel (sold as various brands) TM800A550L */
> + .matches = {
> + DMI_MATCH(DMI_BOARD_VENDOR, "AMI Corporation"),
> + DMI_MATCH(DMI_BOARD_NAME, "Aptio CRB"),
> + /* Above strings are too generic, also match on BIOS version */
> + DMI_MATCH(DMI_BIOS_VERSION, "ZY-8-BI-PX4S70VTR400-X423B-005-D"),
> + },
> + .driver_data = (void *)ACPI_QUIRK_SKIP_I2C_CLIENTS,
> + },
> + {}
> +};
> +
> +static const struct acpi_device_id i2c_acpi_known_good_ids[] = {
> + { "10EC5640", 0 }, /* RealTek ALC5640 audio codec */
> + { "INT33F4", 0 }, /* X-Powers AXP288 PMIC */
> + { "INT33FD", 0 }, /* Intel Crystal Cove PMIC */
> + { "NPCE69A", 0 }, /* Asus Transformer keyboard dock */
> + {}
> +};
> +
> +bool acpi_quirk_skip_i2c_client_enumeration(struct acpi_device *adev)
> +{
> + const struct dmi_system_id *dmi_id;
> + long quirks;
> +
> + dmi_id = dmi_first_match(acpi_skip_serial_bus_enumeration_ids);
> + if (!dmi_id)
> + return false;
> +
> + quirks = (unsigned long)dmi_id->driver_data;
> + if (!(quirks & ACPI_QUIRK_SKIP_I2C_CLIENTS))
> + return false;
> +
> + return acpi_match_device_ids(adev, i2c_acpi_known_good_ids);
> +}
> +EXPORT_SYMBOL_GPL(acpi_quirk_skip_i2c_client_enumeration);
> +
> +int acpi_quirk_skip_serdev_enumeration(struct device *controller_parent, bool *skip)
> +{
> + struct acpi_device *adev = ACPI_COMPANION(controller_parent);
> + const struct dmi_system_id *dmi_id;
> + long quirks = 0;
> +
> + *skip = false;
> +
> + /* !dev_is_platform() to not match on PNP enumerated debug UARTs */
> + if (!adev || !adev->pnp.unique_id || !dev_is_platform(controller_parent))
> + return 0;
> +
> + dmi_id = dmi_first_match(acpi_skip_serial_bus_enumeration_ids);
> + if (dmi_id)
> + quirks = (unsigned long)dmi_id->driver_data;
> +
> + if (quirks & ACPI_QUIRK_UART1_TTY_UART2_SKIP) {
> + if (!strcmp(adev->pnp.unique_id, "1"))
> + return -ENODEV; /* Create tty cdev instead of serdev */
> +
> + if (!strcmp(adev->pnp.unique_id, "2"))
> + *skip = true;
> + }
> +
> + return 0;
> +}
> +EXPORT_SYMBOL_GPL(acpi_quirk_skip_serdev_enumeration);
> +#endif
> diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
> index 5895f6c7f6db..102b1cf433c7 100644
> --- a/include/acpi/acpi_bus.h
> +++ b/include/acpi/acpi_bus.h
> @@ -624,6 +624,22 @@ static inline bool acpi_device_override_status(struct acpi_device *adev,
> }
> #endif
>
> +#if IS_ENABLED(CONFIG_X86_ANDROID_TABLETS)
> +bool acpi_quirk_skip_i2c_client_enumeration(struct acpi_device *adev);
> +int acpi_quirk_skip_serdev_enumeration(struct device *controller_parent, bool *skip);
> +#else
> +static inline bool acpi_quirk_skip_i2c_client_enumeration(struct acpi_device *adev)
> +{
> + return false;
> +}
> +static inline int
> +acpi_quirk_skip_serdev_enumeration(struct device *controller_parent, bool *skip)
> +{
> + *skip = false;
> + return 0;
> +}
> +#endif
> +
> #ifdef CONFIG_PM
> void acpi_pm_wakeup_event(struct device *dev);
> acpi_status acpi_add_pm_notifier(struct acpi_device *adev, struct device *dev,
> --
> 2.33.1
>
