[Bug 2172428] [NEW] Touchpad SYNA2392 not detected on Lenovo 14w Gen 2 (82N9), created as platform device instead of I2C client

Public bug reported: Title: Lenovo 14w Gen 2 (82N9): Synaptics SYNA2392 touchpad not enumerated as I2C client (kernel 7.0.0-42) Hardware: Lenovo 14w Gen 2, model 82N9, AMD 3015e, BIOS LENOVO H0CN30WW (2024-09-18) Software: Linux Mint 22.3 XFCE (Ubuntu-based), kernel 7.0.0-42-generic Windows 11 on the same machine: touchpad worked normally. Problem: the internal touchpad is not detected. xinput list shows no touchpad. Findings: - ACPI: SYNA2392:00 present (status 15), ELAN238E:00 present (status 0). Both have _CID PNP0C50. - SYNA2392:00 is instantiated as a platform device (subsystem -> platform), not as an I2C client. There is no i2c-SYNA2392:00 in /sys/bus/i2c/devices. - Its parent controller AMDI0010:01 is bound to i2c_designware, but /sys/bus/platform/devices/AMDI0010:01/i2c-1/ has no client device. - i2c_hid_acpi and hid_multitouch are loaded or loadable; nothing happens. - No related messages in dmesg, no ACPI errors. - Same result after updating from 7.0.0-38 to 7.0.0-42. DSDT (Scope _SB.I2CD, Device TPD0): _CRS returns an I2cSerialBusV2 resource (0x15 or 0x2C) only if the EC field TPTY equals 1 or 2. For any other value, nothing is returned. Reading TPTY afterwards via ec_sys (offset 0x9F) gives 02, consistent with the Synaptics. Hypothesis (unconfirmed): _CRS is evaluated during enumeration when TPTY is not yet valid, so the device is created without an I2C resource. Question: is this a known issue with this firmware? Happy to test patches or provide more output. ** Affects: linux (Ubuntu) Importance: Undecided Status: New -- You received this bug notification because you are subscribed to linux in Ubuntu. Matching subscriptions: Bgg, Bmail, Nb https://bugs.launchpad.net/bugs/2172428 Title: Touchpad SYNA2392 not detected on Lenovo 14w Gen 2 (82N9), created as platform device instead of I2C client Status in linux package in Ubuntu: New Bug description: Title: Lenovo 14w Gen 2 (82N9): Synaptics SYNA2392 touchpad not enumerated as I2C client (kernel 7.0.0-42) Hardware: Lenovo 14w Gen 2, model 82N9, AMD 3015e, BIOS LENOVO H0CN30WW (2024-09-18) Software: Linux Mint 22.3 XFCE (Ubuntu-based), kernel 7.0.0-42-generic Windows 11 on the same machine: touchpad worked normally. Problem: the internal touchpad is not detected. xinput list shows no touchpad. Findings: - ACPI: SYNA2392:00 present (status 15), ELAN238E:00 present (status 0). Both have _CID PNP0C50. - SYNA2392:00 is instantiated as a platform device (subsystem -> platform), not as an I2C client. There is no i2c-SYNA2392:00 in /sys/bus/i2c/devices. - Its parent controller AMDI0010:01 is bound to i2c_designware, but /sys/bus/platform/devices/AMDI0010:01/i2c-1/ has no client device. - i2c_hid_acpi and hid_multitouch are loaded or loadable; nothing happens. - No related messages in dmesg, no ACPI errors. - Same result after updating from 7.0.0-38 to 7.0.0-42. DSDT (Scope _SB.I2CD, Device TPD0): _CRS returns an I2cSerialBusV2 resource (0x15 or 0x2C) only if the EC field TPTY equals 1 or 2. For any other value, nothing is returned. Reading TPTY afterwards via ec_sys (offset 0x9F) gives 02, consistent with the Synaptics. Hypothesis (unconfirmed): _CRS is evaluated during enumeration when TPTY is not yet valid, so the device is created without an I2C resource. Question: is this a known issue with this firmware? Happy to test patches or provide more output. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/2172428/+subscriptions