1*4882a593Smuzhiyun===================================================== 2*4882a593SmuzhiyunIntel INT3496 ACPI device extcon driver documentation 3*4882a593Smuzhiyun===================================================== 4*4882a593Smuzhiyun 5*4882a593SmuzhiyunThe Intel INT3496 ACPI device extcon driver is a driver for ACPI 6*4882a593Smuzhiyundevices with an acpi-id of INT3496, such as found for example on 7*4882a593SmuzhiyunIntel Baytrail and Cherrytrail tablets. 8*4882a593Smuzhiyun 9*4882a593SmuzhiyunThis ACPI device describes how the OS can read the id-pin of the devices' 10*4882a593SmuzhiyunUSB-otg port, as well as how it optionally can enable Vbus output on the 11*4882a593Smuzhiyunotg port and how it can optionally control the muxing of the data pins 12*4882a593Smuzhiyunbetween an USB host and an USB peripheral controller. 13*4882a593Smuzhiyun 14*4882a593SmuzhiyunThe ACPI devices exposes this functionality by returning an array with up 15*4882a593Smuzhiyunto 3 gpio descriptors from its ACPI _CRS (Current Resource Settings) call: 16*4882a593Smuzhiyun 17*4882a593Smuzhiyun======= ===================================================================== 18*4882a593SmuzhiyunIndex 0 The input gpio for the id-pin, this is always present and valid 19*4882a593SmuzhiyunIndex 1 The output gpio for enabling Vbus output from the device to the otg 20*4882a593Smuzhiyun port, write 1 to enable the Vbus output (this gpio descriptor may 21*4882a593Smuzhiyun be absent or invalid) 22*4882a593SmuzhiyunIndex 2 The output gpio for muxing of the data pins between the USB host and 23*4882a593Smuzhiyun the USB peripheral controller, write 1 to mux to the peripheral 24*4882a593Smuzhiyun controller 25*4882a593Smuzhiyun======= ===================================================================== 26*4882a593Smuzhiyun 27*4882a593SmuzhiyunThere is a mapping between indices and GPIO connection IDs as follows 28*4882a593Smuzhiyun 29*4882a593Smuzhiyun ======= ======= 30*4882a593Smuzhiyun id index 0 31*4882a593Smuzhiyun vbus index 1 32*4882a593Smuzhiyun mux index 2 33*4882a593Smuzhiyun ======= ======= 34