On the Dell Precision 3540/0M14W7, BIOS 1.7.4 05/12/2020, Linux prints the warning below. i801_smbus 0000:00:1f.4: Accelerometer lis3lv02d is present on SMBus but its address is unknown, skipping registration With the help of Wolfram Sang, the test to probe it on I²C bus 6 at address 0x29 was successful. $ cd /sys/bus/pci/drivers/i801_smbus/0000:00:1f.4 $ ls -d i2c-? i2c-6 $ sudo i2cdetect 6 WARNING! This program can confuse your I2C bus, cause data loss and worse! I will probe file /dev/i2c-6. I will probe address range 0x08-0x77. Continue? [Y/n] Y 0 1 2 3 4 5 6 7 8 9 a b c d e f 00: 08 -- -- -- -- -- -- -- 10: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 20: -- -- -- -- -- -- -- -- -- 29 -- -- -- -- -- -- 30: 30 -- -- -- -- 35 UU UU -- -- -- -- -- -- -- -- 40: -- -- -- -- 44 -- -- -- -- -- -- -- -- -- -- -- 50: UU -- 52 -- -- -- -- -- -- -- -- -- -- -- -- -- 60: -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- -- 70: -- -- -- -- -- -- -- -- $ echo lis3lv02d 0x29 | sudo tee /sys/bus/i2c/devices/i2c-6/new_device $ sudo dmesg […] [ 2110.787000] i2c i2c-6: new_device: Instantiated device lis3lv02d at 0x29 [ 2110.791932] lis3lv02d_i2c 6-0029: supply Vdd not found, using dummy regulator [ 2110.791981] lis3lv02d_i2c 6-0029: supply Vdd_IO not found, using dummy regulator [ 2110.809233] lis3lv02d: 8 bits 3DC sensor found [ 2110.900668] input: ST LIS3LV02DL Accelerometer as /devices/platform/lis3lv02d/input/input23 So, the device has that accelerometer. Add the I2C address to the mapping list. Link: https://lore.kernel.org/linux-i2c/97708c11-ac85-fb62-2c8e-d37739ca826f@xxxxxxxxxxxxx/ Signed-off-by: Paul Menzel <pmenzel@xxxxxxxxxxxxx> --- drivers/i2c/busses/i2c-i801.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c index 070999139c6d..cb9660f84117 100644 --- a/drivers/i2c/busses/i2c-i801.c +++ b/drivers/i2c/busses/i2c-i801.c @@ -1230,6 +1230,7 @@ static const struct { * Additional individual entries were added after verification. */ { "Latitude 5480", 0x29 }, + { "Precision 3540", 0x29 }, { "Vostro V131", 0x1d }, { "Vostro 5568", 0x29 }, }; -- 2.43.0