On Thursday 15 February 2024 19:16:33 Pali Rohár wrote: > On Tuesday 13 February 2024 15:07:08 Jean Delvare wrote: > > On Sat, 23 Dec 2023 13:53:50 +0100, Pali Rohár wrote: > > > smbus is not really bus which provides discovering and identifying > > > devices on the bus. > > > > For completeness, SMBus version 2.0 actually added support for device > > discovery and even dynamic slave address allocation. This is explained > > in chapter 5, section 5.6 (SMBus Address resolution protocol). > > > > Unfortunately, this is an optional feature which requires active > > cooperation from each device connected to the bus. If any device on the > > bus supports SMBus ARP then you should get an answer when probing > > (7-bit) I2C address 0x61. > > > > Long ago I had a plan to add support for SMBus ARP to the kernel, but > > gave up because I couldn't find any system implementing it. If the > > accelerometer device in Dell laptops supported ARP then we could use it > > to figure out the device's address, unfortunately this doesn't seem to > > be the case. > > > > -- > > Jean Delvare > > SUSE L3 Support > > According to my notes, accelerometer in Dell laptops should use > LNG3DMTR-LGA16-3x3 chipset. From what I found it should be > pin-compatible with LIS302DL, just in different package. > > ST LIS302DL datasheet is on the website: > https://www.st.com/resource/en/datasheet/lis302dl.pdf > > It is dual i2c and SPI bus support chipset. But in the datasheet there > is nothing about SMBus, looks like this is designed for i2c usage. So I > highly doubt that chipset supports SMBus version 2.0 with ARP extension. Now I checked i2c address 0x61 and nothing responds to it. > Anyway, SMBus ARP is new thing to me, I have never heard about it or its > usage before. Has anybody else found some device which supports it? > Would be interesting to know if this is not just another standard which > was not publicly deployed yet.
