Re: [PATCH] Autocentering support for Logitech MOMO Racing Wheel (force feedback)
From: Dmitry Torokhov <dmitry.torokhov@gmail.com>
Date: 2008-08-18 15:24:25
Hi Sergey, On Mon, Aug 18, 2008 at 01:17:48PM +0400, ???????????? ?????????????? wrote:
Hello. Current kernel has no support for autocentering for Logitech wheels. By default autocentering enabled in wheel and constant effect does not work properly. Using USB sniffer I found command which change autocentering settings: 0xFE, 0x0D, 0x0R, 0x0L, 0x80, 0x00, 0x00, where R - clockwise force, L - counter-clockwise (0x0-0xF, 0xC = 100%). I write patch for my current kernel (2.6.25), but I think git version also supported, because I do not found any changes in it. Currently kernel interface has no support for separate autocenter control and so I do not implement it. And some interesting command 0xF3 (or 0xF5 - I do not understand difference) which makes wheel very easy to rotate (a-la wheel booster - no any resistance). Effect of that command can be disabled by setting any (zero too) autocentering strength. I do not found in kernel interface any standart command for this feature.
This could probably implemented via a sysfs device knob...
error = input_ff_create_memless(dev, NULL, hid_lgff_play); if (error) return error; + if (autocenter && dev->ff && (!dev->ff->set_autocenter)) + dev->ff->set_autocenter = hid_lgff_set_autocenter; +
You can just do "if (test_bit(FF_AUTOCENTER, dev->ffbit))" and you won't need a temp variable. Also why do you need the rest of the check? -- Dmitry