Input: libps2 - additional locking for i8042 ports

The serio ports on i8042 are not completely isolated; while we provide
enough locking to ensure proper serialization when accessing control
and data registers AUX and KBD ports can still have an effect on each
other on PS/2 protocol level. The most prominent effect is that
issuing a command for the device connected to one port may cause
abort of the command currently executing by the device connected to
another port.

Since i8042 nor serio subsystem are not aware of the details of the
PS/2 protocol (length of the commands and their replies and so on) the
locking should be done on libps2 level by adding special handling when
we see that we are dealing with serio port on i8042.

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

1 files changed, 8 insertions, 0 deletions

diff --git a/drivers/leds/leds-clevo-mail.c b/drivers/leds/leds-clevo-mail.c
index 1813c84ea5fc..f2242db54016 100644
--- a/drivers/leds/leds-clevo-mail.c
+++ b/drivers/leds/leds-clevo-mail.c
@@ -93,6 +93,8 @@ static struct dmi_system_id __initdata mail_led_whitelist[] = {
 static void clevo_mail_led_set(struct led_classdev *led_cdev,
                                 enum led_brightness value)
 {
+        i8042_lock_chip();
+
         if (value == LED_OFF)
                 i8042_command(NULL, CLEVO_MAIL_LED_OFF);
         else if (value <= LED_HALF)
@@ -100,6 +102,8 @@ static void clevo_mail_led_set(struct led_classdev *led_cdev,
         else
                 i8042_command(NULL, CLEVO_MAIL_LED_BLINK_1HZ);
 
+        i8042_unlock_chip();
+
 }
 
 static int clevo_mail_led_blink(struct led_classdev *led_cdev,
@@ -108,6 +112,8 @@ static int clevo_mail_led_blink(struct led_classdev *led_cdev,
 {
         int status = -EINVAL;
 
+        i8042_lock_chip();
+
         if (*delay_on == 0 /* ms */ && *delay_off == 0 /* ms */) {
                 /* Special case: the leds subsystem requested us to
                  * chose one user friendly blinking of the LED, and
@@ -135,6 +141,8 @@ static int clevo_mail_led_blink(struct led_classdev *led_cdev,
                        *delay_on, *delay_off);
         }
 
+        i8042_unlock_chip();
+
         return status;
 }