summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorLiam Mitchell <mitchell.liam@gmail.com>2026-02-18 14:21:35 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2026-04-11 14:29:46 +0200
commit62bf2b629edb83c339ef2872ad3f73f415cb2a1a (patch)
treec491f8f6cf7af4d240fbec721007e66ef7625003
parent9988d9bcc6f3773a93c7334d0f0b8b22686a58ea (diff)
Input: bcm5974 - recover from failed mode switch
commit fc1e8a6f129d87c64ac8e58b50d9dfa66217cfda upstream. Mode switches sent before control response are ignored. This results in an unresponsive trackpad and "bcm5974: bad trackpad package, length: 8" repeated in logs. On receiving unknown 8-byte packets, assume that mode switch was ignored and schedule an asynchronous mode reset. The reset will switch the device to normal mode, wait, then switch back to wellspring mode. Signed-off-by: Liam Mitchell <mitchell.liam@gmail.com> Link: https://lore.kernel.org/linux-input/CAOQ1CL4+DP1TuLAGNsz5GdFBTHvnTg=5q=Dr2Z1OQc6RXydSYA@mail.gmail.com/ Acked-by: Henrik Rydberg <rydberg@bitmath.org> Link: https://patch.msgid.link/20260213-bcm5974-reset-v2-1-1837851336b0@gmail.com Cc: stable@vger.kernel.org Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
-rw-r--r--drivers/input/mouse/bcm5974.c42
1 files changed, 41 insertions, 1 deletions
diff --git a/drivers/input/mouse/bcm5974.c b/drivers/input/mouse/bcm5974.c
index dfdfb59cc8b5..fe52f15c0c10 100644
--- a/drivers/input/mouse/bcm5974.c
+++ b/drivers/input/mouse/bcm5974.c
@@ -286,6 +286,8 @@ struct bcm5974 {
const struct tp_finger *index[MAX_FINGERS]; /* finger index data */
struct input_mt_pos pos[MAX_FINGERS]; /* position array */
int slots[MAX_FINGERS]; /* slot assignments */
+ struct work_struct mode_reset_work;
+ unsigned long last_mode_reset;
};
/* trackpad finger block data, le16-aligned */
@@ -696,6 +698,32 @@ static int bcm5974_wellspring_mode(struct bcm5974 *dev, bool on)
return retval;
}
+/*
+ * Mode switches sent before the control response are ignored.
+ * Fixing this state requires switching to normal mode and waiting
+ * about 1ms before switching back to wellspring mode.
+ */
+static void bcm5974_mode_reset_work(struct work_struct *work)
+{
+ struct bcm5974 *dev = container_of(work, struct bcm5974, mode_reset_work);
+ int error;
+
+ guard(mutex)(&dev->pm_mutex);
+ dev->last_mode_reset = jiffies;
+
+ error = bcm5974_wellspring_mode(dev, false);
+ if (error) {
+ dev_err(&dev->intf->dev, "reset to normal mode failed\n");
+ return;
+ }
+
+ fsleep(1000);
+
+ error = bcm5974_wellspring_mode(dev, true);
+ if (error)
+ dev_err(&dev->intf->dev, "mode switch after reset failed\n");
+}
+
static void bcm5974_irq_button(struct urb *urb)
{
struct bcm5974 *dev = urb->context;
@@ -752,10 +780,20 @@ static void bcm5974_irq_trackpad(struct urb *urb)
if (dev->tp_urb->actual_length == 2)
goto exit;
- if (report_tp_state(dev, dev->tp_urb->actual_length))
+ if (report_tp_state(dev, dev->tp_urb->actual_length)) {
dprintk(1, "bcm5974: bad trackpad package, length: %d\n",
dev->tp_urb->actual_length);
+ /*
+ * Receiving a HID packet means we aren't in wellspring mode.
+ * If we haven't tried a reset in the last second, try now.
+ */
+ if (dev->tp_urb->actual_length == 8 &&
+ time_after(jiffies, dev->last_mode_reset + msecs_to_jiffies(1000))) {
+ schedule_work(&dev->mode_reset_work);
+ }
+ }
+
exit:
error = usb_submit_urb(dev->tp_urb, GFP_ATOMIC);
if (error)
@@ -906,6 +944,7 @@ static int bcm5974_probe(struct usb_interface *iface,
dev->intf = iface;
dev->input = input_dev;
dev->cfg = *cfg;
+ INIT_WORK(&dev->mode_reset_work, bcm5974_mode_reset_work);
mutex_init(&dev->pm_mutex);
/* setup urbs */
@@ -998,6 +1037,7 @@ static void bcm5974_disconnect(struct usb_interface *iface)
{
struct bcm5974 *dev = usb_get_intfdata(iface);
+ disable_work_sync(&dev->mode_reset_work);
usb_set_intfdata(iface, NULL);
input_unregister_device(dev->input);