krinkinmu/bootlin

Code for the materials from the Bootlin (http://bootlin.com) kernel course and https://krinkinmu.github.io/

bootlin's Issues

Awesome Work, and small updates

Hello, first let me say thank you! I really realy enjoyed reading your ftdi reverse breakdown. I am in awe and jealous of your skills. So i too your kernel driver, my first attempt it didnt work failed the check in probe. I immediately went to sniffing a working userland tool (should have tried more with stock code) and found a fair amount of differences, here ill list sum;

const u16 FTDI_BIT_MODE_RESET = 0x00ff;
const u16 FTDI_BIT_MODE_MPSSE = 0x02ff;

ret = usb_control_msg(
	ftdi->udev, usb_sndctrlpipe(ftdi->udev, 0),
	/* bRequest = */0x00,
	/* bRequestType = */0x40,
	/* wValue = */0x0000,
	/* wIndex =  */0x0000,
	/* data = */NULL,
	/* size = */0,
	ftdi->io_timeout);
if (ret < 0)
	return ret;

ret = usb_control_msg(
	ftdi->udev, usb_sndctrlpipe(ftdi->udev, 0),
	/* bRequest = */0x03,
	/* bRequestType = */0x40,
	/* wValue = */0x4138,
	/* wIndex =  */0x0001,
	/* data = */NULL,
	/* size = */0,
	ftdi->io_timeout);
if (ret < 0)
	return ret;

ret = usb_control_msg(
	ftdi->udev, usb_sndctrlpipe(ftdi->udev, 0),
	/* bRequest = */0x00,
	/* bRequestType = */0x40,
	/* wValue = */0x0000,
	/* wIndex =  */0x0001,
	/* data = */NULL,
	/* size = */0,
	ftdi->io_timeout);
if (ret < 0)
	return ret;

ret = usb_control_msg(
	ftdi->udev, usb_sndctrlpipe(ftdi->udev, 0),
	/* bRequest = */0x00,
	/* bRequestType = */0x40,
	/* wValue = */0x0001,
	/* wIndex =  */0x0001,
	/* data = */NULL,
	/* size = */0,
	ftdi->io_timeout);
if (ret < 0)
	return ret;

ret = usb_control_msg(
	ftdi->udev, usb_sndctrlpipe(ftdi->udev, 0),
	/* bRequest = */0x00,
	/* bRequestType = */0x40,
	/* wValue = */0x0002,
	/* wIndex =  */0x0001,
	/* data = */NULL,
	/* size = */0,
	ftdi->io_timeout);
if (ret < 0)
	return ret;

As you can see I had to change the RESET, MPSSE and wIindex also added a baudrate change (I dunno either), and still had to remove the check ftdi_mpsse_verify. I then added smbus support and blocked binding to bank B (Im using ft2232h) and everything is working great! Will add kernel mods for speed and bank A/B options and /sys entries for changing speed etc as well when I find time. I realize you probly already know but in case someone stumbles here;

PURGE RX AND TX BUFFERS

	/* bRequest = */0x00,
	/* bRequestType = */0x40,
	/* wValue = */0x0000,
	/* wIndex =  */0x0001,
	/* data = */NULL,
	/* size = */0,

PURGE RX BUFFERS

	/* bRequest = */0x00,
	/* bRequestType = */0x40,
	/* wValue = */0x0001,
	/* wIndex =  */0x0001,
	/* data = */NULL,
	/* size = */0,

PURGE TX BUFFERS

	/* bRequest = */0x00,
	/* bRequestType = */0x40,
	/* wValue = */0x0002,
	/* wIndex =  */0x0001,
	/* data = */NULL,
	/* size = */0,

Ialso get extra 2 bytes on invalid/bad commands i guess an error code. My versions is located here;
https://github.com/bm16ton/ft2232-mpsse-i2c-spi-kern-drivers
and integrated into my kernel here;
https://github.com/bm16ton/yoga-c630-linux-kernel
with hopefully more updates coming soon. Is there any reason this couldnt be submitted for mainline kernel? Again great work and thank you!