Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: (22 commits)
  Input: ALPS - add interleaved protocol support (Dell E6x00 series)
  Input: keyboard - don't override beep with a bell
  Input: altera_ps2 - fix test of unsigned in altera_ps2_probe()
  Input: add mc13783 touchscreen driver
  Input: ep93xx_keypad - update driver to new core support
  Input: wacom - separate pen from express keys on Graphire
  Input: wacom - add defines for data packet report IDs
  Input: wacom - add support for new LCD tablets
  Input: wacom - add defines for packet lengths of various devices
  Input: wacom - ensure the device is initialized properly upon resume
  Input: at32psif - do not sleep in atomic context
  Input: i8042 - add Gigabyte M1022M to the noloop list
  Input: i8042 - allow installing platform filters for incoming data
  Input: i8042 - fix locking in interrupt routine
  Input: ALPS - do not set REL_X/REL_Y capabilities on the touchpad
  Input: document use of input_event() function
  Input: sa1111ps2 - annotate probe() and remove() methods
  Input: ambakmi - annotate probe() and remove() methods
  Input: gscps2 - fix probe() and remove() annotations
  Input: altera_ps2 - add annotations to probe and remove methods
  ...

1 files changed, 79 insertions, 9 deletions

diff --git a/drivers/input/serio/i8042.c b/drivers/input/serio/i8042.c
index 1df02d25aca5..d84a36e545f6 100644
--- a/drivers/input/serio/i8042.c
+++ b/drivers/input/serio/i8042.c
@@ -126,6 +126,8 @@ static unsigned char i8042_suppress_kbd_ack;
 static struct platform_device *i8042_platform_device;
 
 static irqreturn_t i8042_interrupt(int irq, void *dev_id);
+static bool (*i8042_platform_filter)(unsigned char data, unsigned char str,
+                                     struct serio *serio);
 
 void i8042_lock_chip(void)
 {
@@ -139,6 +141,48 @@ void i8042_unlock_chip(void)
 }
 EXPORT_SYMBOL(i8042_unlock_chip);
 
+int i8042_install_filter(bool (*filter)(unsigned char data, unsigned char str,
+                                        struct serio *serio))
+{
+        unsigned long flags;
+        int ret = 0;
+
+        spin_lock_irqsave(&i8042_lock, flags);
+
+        if (i8042_platform_filter) {
+                ret = -EBUSY;
+                goto out;
+        }
+
+        i8042_platform_filter = filter;
+
+out:
+        spin_unlock_irqrestore(&i8042_lock, flags);
+        return ret;
+}
+EXPORT_SYMBOL(i8042_install_filter);
+
+int i8042_remove_filter(bool (*filter)(unsigned char data, unsigned char str,
+                                       struct serio *port))
+{
+        unsigned long flags;
+        int ret = 0;
+
+        spin_lock_irqsave(&i8042_lock, flags);
+
+        if (i8042_platform_filter != filter) {
+                ret = -EINVAL;
+                goto out;
+        }
+
+        i8042_platform_filter = NULL;
+
+out:
+        spin_unlock_irqrestore(&i8042_lock, flags);
+        return ret;
+}
+EXPORT_SYMBOL(i8042_remove_filter);
+
 /*
  * The i8042_wait_read() and i8042_wait_write functions wait for the i8042 to
  * be ready for reading values from it / writing values to it.
@@ -369,6 +413,31 @@ static void i8042_stop(struct serio *serio)
 }
 
 /*
+ * i8042_filter() filters out unwanted bytes from the input data stream.
+ * It is called from i8042_interrupt and thus is running with interrupts
+ * off and i8042_lock held.
+ */
+static bool i8042_filter(unsigned char data, unsigned char str,
+                         struct serio *serio)
+{
+        if (unlikely(i8042_suppress_kbd_ack)) {
+                if ((~str & I8042_STR_AUXDATA) &&
+                    (data == 0xfa || data == 0xfe)) {
+                        i8042_suppress_kbd_ack--;
+                        dbg("Extra keyboard ACK - filtered out\n");
+                        return true;
+                }
+        }
+
+        if (i8042_platform_filter && i8042_platform_filter(data, str, serio)) {
+                dbg("Filtered out by platfrom filter\n");
+                return true;
+        }
+
+        return false;
+}
+
+/*
  * i8042_interrupt() is the most important function in this driver -
  * it handles the interrupts from the i8042, and sends incoming bytes
  * to the upper layers.
@@ -377,13 +446,16 @@ static void i8042_stop(struct serio *serio)
 static irqreturn_t i8042_interrupt(int irq, void *dev_id)
 {
         struct i8042_port *port;
+        struct serio *serio;
         unsigned long flags;
         unsigned char str, data;
         unsigned int dfl;
         unsigned int port_no;
+        bool filtered;
         int ret = 1;
 
         spin_lock_irqsave(&i8042_lock, flags);
+
         str = i8042_read_status();
         if (unlikely(~str & I8042_STR_OBF)) {
                 spin_unlock_irqrestore(&i8042_lock, flags);
@@ -391,8 +463,8 @@ static irqreturn_t i8042_interrupt(int irq, void *dev_id)
                 ret = 0;
                 goto out;
         }
+
         data = i8042_read_data();
-        spin_unlock_irqrestore(&i8042_lock, flags);
 
         if (i8042_mux_present && (str & I8042_STR_AUXDATA)) {
                 static unsigned long last_transmit;
@@ -441,21 +513,19 @@ static irqreturn_t i8042_interrupt(int irq, void *dev_id)
         }
 
         port = &i8042_ports[port_no];
+        serio = port->exists ? port->serio : NULL;
 
         dbg("%02x <- i8042 (interrupt, %d, %d%s%s)",
             data, port_no, irq,
             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--;
-                        goto out;
-                }
+        filtered = i8042_filter(data, str, serio);
+
+        spin_unlock_irqrestore(&i8042_lock, flags);
 
-        if (likely(port->exists))
-                serio_interrupt(port->serio, data, dfl);
+        if (likely(port->exists && !filtered))
+                serio_interrupt(serio, data, dfl);
 
  out:
         return IRQ_RETVAL(ret);