| Message ID | 20190311112216.31391-3-hdegoede@redhat.com |
|---|---|
| State | Superseded |
| Headers | show |
| Series | intel-lpss-pci-i2c: Fix oops when there is no ACPI fwnode | expand |
On Mon, Mar 11, 2019 at 12:22:16PM +0100, Hans de Goede wrote: > The i2c-designware-platdrv assumes that if the pdev has an apci-companion > it should use a dynamic adapter-nr and otherwise it will use pdev->id as > adapter-nr. > > On some devices e.g. the Apollo Lake using Acer TravelMate Spin B118, > some of the LPSS i2c-adapters are enumerated through PCI and do not have > an ACPI fwnode. These devices are handled as mfd devices so they end up > using the i2c-designware-platdrv driver. > > This results in the i2c-adapter being registered with the mfd generated > pdev->id as adapter-nr, which conflicts with existing adapters, triggering > a WARN(id < 0, "couldn't get idr") in i2c-core-base.c and causing the > adapter registration to fail. > > To fix this the i2c-designware-platdrv now also supports a > "linux,use-dynamic-adapter-nr" device-property, which tells it to use a > dynamic adapter nr even if there is no ACPI fwnode for the device. > > This commit adds this device-property to the properties list for PCI > enumerated LPSS i2c-adapters. > > BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1687065 > Signed-off-by: Hans de Goede <hdegoede@redhat.com> You need to CC the devicetree ML on such patches. However, I am afraid I can pretty much NACK this one already. This is a Linux configuration item and DT is only for describing HW. Maybe the designware maintainers have a better idea how to achieve what you need.
diff --git a/drivers/mfd/intel-lpss-pci.c b/drivers/mfd/intel-lpss-pci.c index 0e5282fc1467..c7b84a0f090e 100644 --- a/drivers/mfd/intel-lpss-pci.c +++ b/drivers/mfd/intel-lpss-pci.c @@ -69,6 +69,7 @@ static const struct intel_lpss_platform_info spt_info = { static struct property_entry spt_i2c_properties[] = { PROPERTY_ENTRY_U32("i2c-sda-hold-time-ns", 230), + PROPERTY_ENTRY_BOOL("linux,use-dynamic-adapter-nr"), { }, }; @@ -104,6 +105,7 @@ static struct property_entry bxt_i2c_properties[] = { PROPERTY_ENTRY_U32("i2c-sda-hold-time-ns", 42), PROPERTY_ENTRY_U32("i2c-sda-falling-time-ns", 171), PROPERTY_ENTRY_U32("i2c-scl-falling-time-ns", 208), + PROPERTY_ENTRY_BOOL("linux,use-dynamic-adapter-nr"), { }, }; @@ -116,6 +118,7 @@ static struct property_entry apl_i2c_properties[] = { PROPERTY_ENTRY_U32("i2c-sda-hold-time-ns", 207), PROPERTY_ENTRY_U32("i2c-sda-falling-time-ns", 171), PROPERTY_ENTRY_U32("i2c-scl-falling-time-ns", 208), + PROPERTY_ENTRY_BOOL("linux,use-dynamic-adapter-nr"), { }, };
The i2c-designware-platdrv assumes that if the pdev has an apci-companion it should use a dynamic adapter-nr and otherwise it will use pdev->id as adapter-nr. On some devices e.g. the Apollo Lake using Acer TravelMate Spin B118, some of the LPSS i2c-adapters are enumerated through PCI and do not have an ACPI fwnode. These devices are handled as mfd devices so they end up using the i2c-designware-platdrv driver. This results in the i2c-adapter being registered with the mfd generated pdev->id as adapter-nr, which conflicts with existing adapters, triggering a WARN(id < 0, "couldn't get idr") in i2c-core-base.c and causing the adapter registration to fail. To fix this the i2c-designware-platdrv now also supports a "linux,use-dynamic-adapter-nr" device-property, which tells it to use a dynamic adapter nr even if there is no ACPI fwnode for the device. This commit adds this device-property to the properties list for PCI enumerated LPSS i2c-adapters. BugLink: https://bugzilla.redhat.com/show_bug.cgi?id=1687065 Signed-off-by: Hans de Goede <hdegoede@redhat.com> --- drivers/mfd/intel-lpss-pci.c | 3 +++ 1 file changed, 3 insertions(+)