Commit 463a4f76 authored by Dmitry Torokhov's avatar Dmitry Torokhov
Browse files

Input: i8042 - don't use negation to mark AUX data 



Currently i8042_command() negates data coming from the AUX port
of keyboard controller; this is not a very reliable indicator.
Change i8042_command() to fail if response to I8042_CMD_AUX_LOOP
is not coming from AUX channel and get rid of negation.

Based on patch by Vojtech Pavlik.

Signed-off-by: default avatarDmitry Torokhov <dtor@mail.ru>
parent 7b4019d0

drivers/input/serio/i8042.c

+32 −28
Original line number Diff line number Diff line
@@ -191,41 +191,45 @@ static int i8042_flush(void) 
static int i8042_command(unsigned char *param, int command)

{

	unsigned long flags;

	int retval = 0, i = 0;

	int i, retval, auxerr = 0;



	if (i8042_noloop && command == I8042_CMD_AUX_LOOP)

		return -1;



	spin_lock_irqsave(&i8042_lock, flags);



	retval = i8042_wait_write();

	if (!retval) {

	if ((retval = i8042_wait_write()))

		goto out;



	dbg("%02x -> i8042 (command)", command & 0xff);

	i8042_write_command(command & 0xff);

	}



	if (!retval)

	for (i = 0; i < ((command >> 12) & 0xf); i++) {

			if ((retval = i8042_wait_write())) break;

		if ((retval = i8042_wait_write()))

			goto out;

		dbg("%02x -> i8042 (parameter)", param[i]);

		i8042_write_data(param[i]);

	}



	if (!retval)

	for (i = 0; i < ((command >> 8) & 0xf); i++) {

			if ((retval = i8042_wait_read())) break;

			if (i8042_read_status() & I8042_STR_AUXDATA)

				param[i] = ~i8042_read_data();

			else

		if ((retval = i8042_wait_read()))

			goto out;



		if (command == I8042_CMD_AUX_LOOP &&

		    !(i8042_read_status() & I8042_STR_AUXDATA)) {

			retval = auxerr = -1;

			goto out;

		}



		param[i] = i8042_read_data();

		dbg("%02x <- i8042 (return)", param[i]);

	}



	spin_unlock_irqrestore(&i8042_lock, flags);



	if (retval)

		dbg("     -- i8042 (timeout)");

		dbg("     -- i8042 (%s)", auxerr ? "auxerr" : "timeout");



 out:

	spin_unlock_irqrestore(&i8042_lock, flags);

	return retval;

}
@@ -507,17 +511,17 @@ static int i8042_set_mux_mode(unsigned int mode, unsigned char *mux_version) 
 */



	param = 0xf0;

	if (i8042_command(&param, I8042_CMD_AUX_LOOP) || param != 0x0f)

	if (i8042_command(&param, I8042_CMD_AUX_LOOP) || param != 0xf0)

		return -1;

	param = mode ? 0x56 : 0xf6;

	if (i8042_command(&param, I8042_CMD_AUX_LOOP) || param != (mode ? 0xa9 : 0x09))

	if (i8042_command(&param, I8042_CMD_AUX_LOOP) || param != (mode ? 0x56 : 0xf6))

		return -1;

	param = mode ? 0xa4 : 0xa5;

	if (i8042_command(&param, I8042_CMD_AUX_LOOP) || param == (mode ? 0x5b : 0x5a))

	if (i8042_command(&param, I8042_CMD_AUX_LOOP) || param == (mode ? 0xa4 : 0xa5))

		return -1;



	if (mux_version)

		*mux_version = ~param;

		*mux_version = param;



	return 0;

}
@@ -619,7 +623,7 @@ static int __init i8042_check_aux(void) 
 */



	param = 0x5a;

	if (i8042_command(&param, I8042_CMD_AUX_LOOP) || param != 0xa5) {

	if (i8042_command(&param, I8042_CMD_AUX_LOOP) || param != 0x5a) {



/*

 * External connection test - filters out AT-soldered PS/2 i8042's

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