From 867d2682e92a3999e3862f1679cfcb549142d776 Mon Sep 17 00:00:00 2001 From: Peter Osterlund Date: Fri, 16 Mar 2007 00:58:37 -0400 Subject: [PATCH] Input: sermouse - improve protocol error recovery When using MS protocol the driver should wait for a byte with bit 6 set before assuming that it sees beginning of a data packet. This should allow driver better cope with lost bytes and prevent spurious left/right button events when serial communication is disturbed by a CPU-hungry real-time process. Also fix some formatting. Signed-off-by: Peter Osterlund Signed-off-by: Dmitry Torokhov --- drivers/input/mouse/sermouse.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) diff --git a/drivers/input/mouse/sermouse.c b/drivers/input/mouse/sermouse.c index a85d74710b4..0ac448a82bd 100644 --- a/drivers/input/mouse/sermouse.c +++ b/drivers/input/mouse/sermouse.c @@ -69,7 +69,8 @@ static void sermouse_process_msc(struct sermouse *sermouse, signed char data) switch (sermouse->count) { case 0: - if ((data & 0xf8) != 0x80) return; + if ((data & 0xf8) != 0x80) + return; input_report_key(dev, BTN_LEFT, !(data & 4)); input_report_key(dev, BTN_RIGHT, !(data & 1)); input_report_key(dev, BTN_MIDDLE, !(data & 2)); @@ -107,7 +108,10 @@ static void sermouse_process_ms(struct sermouse *sermouse, signed char data) struct input_dev *dev = sermouse->dev; signed char *buf = sermouse->buf; - if (data & 0x40) sermouse->count = 0; + if (data & 0x40) + sermouse->count = 0; + else if (sermouse->count == 0) + return; switch (sermouse->count) { @@ -169,7 +173,8 @@ static void sermouse_process_ms(struct sermouse *sermouse, signed char data) case 5: case 7: /* Ignore anything besides MZ++ */ - if (sermouse->type != SERIO_MZPP) break; + if (sermouse->type != SERIO_MZPP) + break; switch (buf[1]) { @@ -206,13 +211,16 @@ static irqreturn_t sermouse_interrupt(struct serio *serio, { struct sermouse *sermouse = serio_get_drvdata(serio); - if (time_after(jiffies, sermouse->last + HZ/10)) sermouse->count = 0; + if (time_after(jiffies, sermouse->last + HZ/10)) + sermouse->count = 0; + sermouse->last = jiffies; if (sermouse->type > SERIO_SUN) sermouse_process_ms(sermouse, data); else sermouse_process_msc(sermouse, data); + return IRQ_HANDLED; }