Input: i8042 - supress ACK/NAKs when blinking during panic

This allows using SysRq and not fill logs with complaints from atkbd.

Signed-off-by: Dmitry Torokhov <dtor@mail.ru>

diff --git a/drivers/input/serio/i8042.c b/drivers/input/serio/i8042.c
index 09b06e6..7e3141f 100644 (file)
--- a/drivers/input/serio/i8042.c
+++ b/drivers/input/serio/i8042.c
@@ -106,6 +106,7 @@ static unsigned char i8042_ctr;
 static unsigned char i8042_mux_present;
 static unsigned char i8042_kbd_irq_registered;
 static unsigned char i8042_aux_irq_registered;
+static unsigned char i8042_suppress_kbd_ack;
 static struct platform_device *i8042_platform_device;
 
 static irqreturn_t i8042_interrupt(int irq, void *dev_id);
@@ -316,7 +317,7 @@ static irqreturn_t i8042_interrupt(int irq, void *dev_id)
        unsigned char str, data;
        unsigned int dfl;
        unsigned int port_no;
-       int ret;
+       int ret = 1;
 
        spin_lock_irqsave(&i8042_lock, flags);
        str = i8042_read_status();
@@ -378,10 +379,16 @@ static irqreturn_t i8042_interrupt(int irq, void *dev_id)
            dfl & SERIO_PARITY ? ", bad parity" : "",
            dfl & SERIO_TIMEOUT ? ", timeout" : "");
 
+       if (unlikely(i8042_suppress_kbd_ack))
+               if (port_no == I8042_KBD_PORT_NO &&
+                   (data == 0xfa || data == 0xfe)) {
+                       i8042_suppress_kbd_ack = 0;
+                       goto out;
+               }
+
        if (likely(port->exists))
                serio_interrupt(port->serio, data, dfl);
 
-       ret = 1;
  out:
        return IRQ_RETVAL(ret);
 }
@@ -842,11 +849,13 @@ static long i8042_panic_blink(long count)
        led ^= 0x01 | 0x04;
        while (i8042_read_status() & I8042_STR_IBF)
                DELAY;
+       i8042_suppress_kbd_ack = 1;
        i8042_write_data(0xed); /* set leds */
        DELAY;
        while (i8042_read_status() & I8042_STR_IBF)
                DELAY;
        DELAY;
+       i8042_suppress_kbd_ack = 1;
        i8042_write_data(led);
        DELAY;
        last_blink = count;