On Fri, 4 Dec 2009 10:11:03 -0800, Darrick J. Wong wrote: > On some old IBM workstations and desktop computers, the BIOS presents in the > DSDT an SMBus object that is missing the HID identifier that the i2c-scmi > driver looks for. Modify the ACPI device scan code to insert the missing HID > if it finds an IBM system with such an object. This patch requires Crane > Cai's > update to i2c-scmi to work around incorrectly named methods within the SMBus > control object. > > Affected machines: ThinkCenter M52, IntelliStation Z20/Z30. Note that the > i2c-i801 driver no longer works on these machines because of ACPI resource > conflicts. > > Signed-off-by: Darrick J. Wong <[email protected]> > --- > > drivers/acpi/scan.c | 38 ++++++++++++++++++++++++++++++++++++++ > include/acpi/acpi_drivers.h | 2 ++ > 2 files changed, 40 insertions(+), 0 deletions(-) > > > diff --git a/drivers/acpi/scan.c b/drivers/acpi/scan.c > index 14a7481..5a24429 100644 > --- a/drivers/acpi/scan.c > +++ b/drivers/acpi/scan.c > @@ -8,6 +8,7 @@ > #include <linux/acpi.h> > #include <linux/signal.h> > #include <linux/kthread.h> > +#include <linux/dmi.h> > > #include <acpi/acpi_drivers.h> > > @@ -1014,6 +1015,41 @@ static void acpi_add_id(struct acpi_device *device, > const char *dev_id) > list_add_tail(&id->list, &device->pnp.ids); > } > > +/* > + * Old IBM workstations have a DSDT bug wherein the SMBus object > + * lacks the SMBUS01 HID and the methods do not have the necessary "_" > + * prefix. Work around this. > + */ > +static int acpi_ibm_smbus_match(struct acpi_device *device) > +{ > + acpi_handle h_dummy; > + struct acpi_buffer path = {ACPI_ALLOCATE_BUFFER, NULL}; > + int result; > + > + if (!dmi_name_in_vendors("IBM")) > + return -ENODEV; > + > + /* Look for SMBS object */ > + result = acpi_get_name(device->handle, ACPI_SINGLE_NAME, &path); > + if (result) > + return result; > + > + if (strcmp("SMBS", path.pointer)) { > + result = -ENODEV; > + goto out; > + } > + > + /* Does it have the necessary (but misnamed) methods? */ > + result = -ENODEV; > + if (ACPI_SUCCESS(acpi_get_handle(device->handle, "SBI", &h_dummy)) && > + ACPI_SUCCESS(acpi_get_handle(device->handle, "SBR", &h_dummy)) && > + ACPI_SUCCESS(acpi_get_handle(device->handle, "SBW", &h_dummy))) > + result = 0; > +out: > + kfree(path.pointer); > + return result; > +} > + > static void acpi_device_set_id(struct acpi_device *device) > { > acpi_status status; > @@ -1064,6 +1100,8 @@ static void acpi_device_set_id(struct acpi_device > *device) > acpi_add_id(device, ACPI_BAY_HID); > else if (ACPI_SUCCESS(acpi_dock_match(device))) > acpi_add_id(device, ACPI_DOCK_HID); > + else if (!acpi_ibm_smbus_match(device)) > + acpi_add_id(device, ACPI_SMBUS_IBM_HID); > > break; > case ACPI_BUS_TYPE_POWER: > diff --git a/include/acpi/acpi_drivers.h b/include/acpi/acpi_drivers.h > index f4906f6..83a2960 100644 > --- a/include/acpi/acpi_drivers.h > +++ b/include/acpi/acpi_drivers.h > @@ -65,6 +65,8 @@ > #define ACPI_VIDEO_HID "LNXVIDEO" > #define ACPI_BAY_HID "LNXIOBAY" > #define ACPI_DOCK_HID "LNXDOCK" > +/* Quirk for broken IBM BIOSes */ > +#define ACPI_SMBUS_IBM_HID "SMBUSIBM" > > /* > * For fixed hardware buttons, we fabricate acpi_devices with HID
Bjorn, Len, can you please apply this quickly? The i2c-scmi side of the changes is pending for weeks now, but I can't apply it as long as the ACPI parts aren't in. Thanks, -- Jean Delvare -- To unsubscribe from this list: send the line "unsubscribe linux-i2c" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
