From 94a421ba2ac49efbaa9fe505c64d6e73aadbb769 Mon Sep 17 00:00:00 2001 From: Lingfeng Yang Date: Fri, 18 Dec 2015 12:04:43 -0800 Subject: [PATCH] ANDROID: input: goldfish_events: no extra EV_SYN; register goldfish If we send SYN_REPORT on every single multitouch event, it breaks the multitouch. The multitouch becomes janky and having to click 2-3 times to do stuff (plus randomly activating notification bars when not clicking) If we suppress these SYN_REPORTS, multitouch will work fine, plus the events will have a protocol that looks nice. In addition, we need to register Goldfish Events as a multitouch device by issuing input_mt_init_slots, otherwise input_handle_abs_event in drivers/input/input.c will silently drop all ABS_MT_SLOT events, making it so that touches with more than 1 finger do not work properly. Signed-off-by: "Lingfeng Yang" Change-Id: Ib2350f7d1732449d246f6f0d9b7b08f02cc7c2dd (cherry picked from commit 6cf40d0a16330e1ef42bdf07d9aba6c16ee11fbc) --- drivers/input/keyboard/goldfish_events.c | 28 +++++++++++++++++++++++- 1 file changed, 27 insertions(+), 1 deletion(-) diff --git a/drivers/input/keyboard/goldfish_events.c b/drivers/input/keyboard/goldfish_events.c index f6e643b589b6..c877e56a9bd5 100644 --- a/drivers/input/keyboard/goldfish_events.c +++ b/drivers/input/keyboard/goldfish_events.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include #include @@ -24,6 +25,8 @@ #include #include +#define GOLDFISH_MAX_FINGERS 5 + enum { REG_READ = 0x00, REG_SET_PAGE = 0x00, @@ -52,7 +55,21 @@ static irqreturn_t events_interrupt(int irq, void *dev_id) value = __raw_readl(edev->addr + REG_READ); input_event(edev->input, type, code, value); - input_sync(edev->input); + // Send an extra (EV_SYN, SYN_REPORT, 0x0) event + // if a key was pressed. Some keyboard device + // drivers may only send the EV_KEY event and + // not EV_SYN. + // Note that sending an extra SYN_REPORT is not + // necessary nor correct protocol with other + // devices such as touchscreens, which will send + // their own SYN_REPORT's when sufficient event + // information has been collected (e.g., for + // touchscreens, when pressure and X/Y coordinates + // have been received). Hence, we will only send + // this extra SYN_REPORT if type == EV_KEY. + if (type == EV_KEY) { + input_sync(edev->input); + } return IRQ_HANDLED; } @@ -154,6 +171,15 @@ static int events_probe(struct platform_device *pdev) input_dev->name = edev->name; input_dev->id.bustype = BUS_HOST; + // Set the Goldfish Device to be multi-touch. + // In the Ranchu kernel, there is multi-touch-specific + // code for handling ABS_MT_SLOT events. + // See drivers/input/input.c:input_handle_abs_event. + // If we do not issue input_mt_init_slots, + // the kernel will filter out needed ABS_MT_SLOT + // events when we touch the screen in more than one place, + // preventing multi-touch with more than one finger from working. + input_mt_init_slots(input_dev, GOLDFISH_MAX_FINGERS, 0); events_import_bits(edev, input_dev->evbit, EV_SYN, EV_MAX); events_import_bits(edev, input_dev->keybit, EV_KEY, KEY_MAX); -- 2.20.1