Hi all, maybe instead of stalling the entire init() function it'd be better to put a request to disable autocentering on a workqueue and start a delayed work once the init() function is done setting the wheel up? There'd be a bit more code to write though...
Michal On Tuesday, October 25, 2016 7:26:12 PM CEST Simon Wood wrote: > A number of wheels (G27/etc) do a little full right/full left 'dance' > when first plugged in. This patch inserts a delay so that this 'dance' > is completed before we disable (set to zero) the autocenter spring. > > A side benefit is that the DFGT was confused without the delay, and is > now correctly being set to 900' rotation mode. > > Side Effect - and the reason I am sending as RFC. This 8s delay seems > to have an effect on other wheels connected at the same time. > > With 3 wheels on a hub, and then the hub connected to PC. The wheel > on the right in video below waits for G27 to complete this 8s, before > it will do it's 'dance' and register with the system. > > https://www.youtube.com/watch?v=xCVpCw_yGgA > > I don't know if this is a problem, or if someone here has suggestions > on a better way to implement the delay... > --- > drivers/hid/hid-lg4ff.c | 10 ++++++++++ > 1 file changed, 10 insertions(+) > > diff --git a/drivers/hid/hid-lg4ff.c b/drivers/hid/hid-lg4ff.c > index af3a8ec..3eee920 100644 > --- a/drivers/hid/hid-lg4ff.c > +++ b/drivers/hid/hid-lg4ff.c > @@ -1248,6 +1248,8 @@ int lg4ff_init(struct hid_device *hid) > /* Check if autocentering is available and > * set the centering force to zero by default */ > if (test_bit(FF_AUTOCENTER, dev->ffbit)) { > + wait_queue_head_t wait; > + > /* Formula Force EX expects different autocentering command */ > if ((bcdDevice >> 8) == LG4FF_FFEX_REV_MAJ && > (bcdDevice & 0xff) == LG4FF_FFEX_REV_MIN) > @@ -1255,6 +1257,14 @@ int lg4ff_init(struct hid_device *hid) > else > dev->ff->set_autocenter = lg4ff_set_autocenter_default; > > + /* insert a 8s delay to allow DFGT/G25/G27/G29 wheels to return > to center > position*/ + if (lg4ff_devices[i].product_id == > USB_DEVICE_ID_LOGITECH_DFGT_WHEEL || + lg4ff_devices[i].product_id == > USB_DEVICE_ID_LOGITECH_G25_WHEEL || + > lg4ff_devices[i].product_id == > USB_DEVICE_ID_LOGITECH_G27_WHEEL || + > lg4ff_devices[i].product_id == > USB_DEVICE_ID_LOGITECH_G29_WHEEL) { + init_waitqueue_head > (&wait); > + wait_event_interruptible_timeout(wait, 0, > msecs_to_jiffies(8000)); > + } > dev->ff->set_autocenter(dev, 0); > }
