On 10/8/24 5:41 PM, Venkatesh Yadav Abbarapu wrote:
Add i2c initialization hook and set usb5744 platform data with function having required i2c initialization sequence.
Apart from the USB command attach, prevent the hub from suspend. when the “USB Attach with SMBUS (0xAA56)” command is issued to the hub, the hub is getting enumerated and then it puts in a suspend mode. This causes the hub to NAK any SMBUS access made by the SMBUS Master during this period and not able to see the hub's slave address while running the "i2c probe" command.
Prevent the MCU from the putting the HUB in suspend mode through register write. The BYPASS_UDC_SUSPEND bit (Bit 3) of the RuntimeFlags2 register at address 0x411D controls this aspect of the hub. The BYPASS_UDC_SUSPEND bit in register 0x411Dh must be set to ensure that the MCU is always enabled and ready to respond to SMBus runtime commands. This register needs to be written before the USB attach command is issued. The byte sequence is as follows: Slave addr: 0x2d 00 00 05 00 01 41 1D 08 Slave addr: 0x2d 99 37 00 Slave addr: 0x2d AA 56 00
Signed-off-by: Venkatesh Yadav Abbarapu venkatesh.abbarapu@amd.com
Reviewed-by: Marek Vasut marex@denx.de