Felix Held has submitted this change. ( https://review.coreboot.org/c/coreboot/+/60174 )
Change subject: drivers/i2c/generic: Print error when using _CRS and PowerResource ......................................................................
drivers/i2c/generic: Print error when using _CRS and PowerResource
Exposing the GPIOs via an ACPI PowerResource and the _CRS results in the OS driver and ACPI thinking they own the GPIO. This can cause timing problems because it's not clear which system should be controlling the GPIO. I'm making this an error because we should really clean these up.
BUG=b:210694108 TEST=Boot guybrush and see error:
I2C: 02:5d: ERROR: Exposing GPIOs in Power Resource and _CRS _SB.I2C1.H05D: Goodix Touchscreen at I2C: 02:5d
Signed-off-by: Raul E Rangel rrangel@chromium.org Change-Id: Ifcc42ed81fff295fb168a0b343e96b3a650b1c84 Reviewed-on: https://review.coreboot.org/c/coreboot/+/60174 Tested-by: build bot (Jenkins) no-reply@coreboot.org Reviewed-by: Tim Van Patten timvp@google.com --- M src/drivers/i2c/generic/generic.c 1 file changed, 33 insertions(+), 0 deletions(-)
Approvals: build bot (Jenkins): Verified Raul Rangel: Looks good to me, but someone else must approve Tim Van Patten: Looks good to me, approved
diff --git a/src/drivers/i2c/generic/generic.c b/src/drivers/i2c/generic/generic.c index 981c2d9..15fe7ad 100644 --- a/src/drivers/i2c/generic/generic.c +++ b/src/drivers/i2c/generic/generic.c @@ -77,6 +77,16 @@ } }
+ if (config->has_power_resource && !config->disable_gpio_export_in_crs) { + /* + * This case will most likely cause timing problems. The OS driver might be + * controlling the GPIOs, but the ACPI Power Resource will also be controlling + * them. This will result in the two fighting and stomping on each other. + */ + printk(BIOS_ERR, "%s: Exposing GPIOs in Power Resource and _CRS\n", + dev_path(dev)); + } + /* Device */ acpigen_write_scope(scope); acpigen_write_device(acpi_device_name(dev));