From bc5d04822bd9f34ea93a681f05f5e5683935d574 Mon Sep 17 00:00:00 2001 From: Adam Kropelin Date: Mon, 11 Jul 2005 01:09:32 -0500 Subject: [PATCH] Input: HID - only report events coming from interrupts to hiddev Currently hid-core follows the same code path for input reports regardless of whether they are a result of interrupt transfers or control transfers. That leads to interrupt events erroneously being reported to hiddev for regular control transfers. Prior to 2.6.12 the problem was mitigated by the fact that reporting to hiddev is supressed if the field value has not changed, which is often the case. Said filtering was removed in 2.6.12-rc1 which means any input reports fetched via control transfers result in hiddev interrupt events. This behavior can quickly lead to a feedback loop where a userspace app, in response to interrupt events, issues control transfers which in turn create more interrupt events. This patch prevents input reports that arrive via control transfers from being reported to hiddev as interrupt events. Signed-off-by: Adam Kropelin Signed-off-by: Vojtech Pavlik Signed-off-by: Dmitry Torokhov --- drivers/usb/input/hid-core.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/drivers/usb/input/hid-core.c b/drivers/usb/input/hid-core.c index 271f5bdb8bb3..30b1b2dae731 100644 --- a/drivers/usb/input/hid-core.c +++ b/drivers/usb/input/hid-core.c @@ -789,12 +789,12 @@ static __inline__ int search(__s32 *array, __s32 value, unsigned n) return -1; } -static void hid_process_event(struct hid_device *hid, struct hid_field *field, struct hid_usage *usage, __s32 value, struct pt_regs *regs) +static void hid_process_event(struct hid_device *hid, struct hid_field *field, struct hid_usage *usage, __s32 value, int interrupt, struct pt_regs *regs) { hid_dump_input(usage, value); if (hid->claimed & HID_CLAIMED_INPUT) hidinput_hid_event(hid, field, usage, value, regs); - if (hid->claimed & HID_CLAIMED_HIDDEV) + if (hid->claimed & HID_CLAIMED_HIDDEV && interrupt) hiddev_hid_event(hid, field, usage, value, regs); } @@ -804,7 +804,7 @@ static void hid_process_event(struct hid_device *hid, struct hid_field *field, s * reporting to the layer). */ -static void hid_input_field(struct hid_device *hid, struct hid_field *field, __u8 *data, struct pt_regs *regs) +static void hid_input_field(struct hid_device *hid, struct hid_field *field, __u8 *data, int interrupt, struct pt_regs *regs) { unsigned n; unsigned count = field->report_count; @@ -831,19 +831,19 @@ static void hid_input_field(struct hid_device *hid, struct hid_field *field, __u for (n = 0; n < count; n++) { if (HID_MAIN_ITEM_VARIABLE & field->flags) { - hid_process_event(hid, field, &field->usage[n], value[n], regs); + hid_process_event(hid, field, &field->usage[n], value[n], interrupt, regs); continue; } if (field->value[n] >= min && field->value[n] <= max && field->usage[field->value[n] - min].hid && search(value, field->value[n], count)) - hid_process_event(hid, field, &field->usage[field->value[n] - min], 0, regs); + hid_process_event(hid, field, &field->usage[field->value[n] - min], 0, interrupt, regs); if (value[n] >= min && value[n] <= max && field->usage[value[n] - min].hid && search(field->value, value[n], count)) - hid_process_event(hid, field, &field->usage[value[n] - min], 1, regs); + hid_process_event(hid, field, &field->usage[value[n] - min], 1, interrupt, regs); } memcpy(field->value, value, count * sizeof(__s32)); @@ -851,7 +851,7 @@ exit: kfree(value); } -static int hid_input_report(int type, struct urb *urb, struct pt_regs *regs) +static int hid_input_report(int type, struct urb *urb, int interrupt, struct pt_regs *regs) { struct hid_device *hid = urb->context; struct hid_report_enum *report_enum = hid->report_enum + type; @@ -899,7 +899,7 @@ static int hid_input_report(int type, struct urb *urb, struct pt_regs *regs) hiddev_report_event(hid, report); for (n = 0; n < report->maxfield; n++) - hid_input_field(hid, report->field[n], data, regs); + hid_input_field(hid, report->field[n], data, interrupt, regs); if (hid->claimed & HID_CLAIMED_INPUT) hidinput_report_event(hid, report); @@ -918,7 +918,7 @@ static void hid_irq_in(struct urb *urb, struct pt_regs *regs) switch (urb->status) { case 0: /* success */ - hid_input_report(HID_INPUT_REPORT, urb, regs); + hid_input_report(HID_INPUT_REPORT, urb, 1, regs); break; case -ECONNRESET: /* unlink */ case -ENOENT: @@ -1142,7 +1142,7 @@ static void hid_ctrl(struct urb *urb, struct pt_regs *regs) switch (urb->status) { case 0: /* success */ if (hid->ctrl[hid->ctrltail].dir == USB_DIR_IN) - hid_input_report(hid->ctrl[hid->ctrltail].report->type, urb, regs); + hid_input_report(hid->ctrl[hid->ctrltail].report->type, urb, 0, regs); case -ESHUTDOWN: /* unplug */ case -EILSEQ: /* unplug timectrl on uhci */ unplug = 1; -- 2.39.2