Input: add ps2_drain() to libps2 to allow reading and discarding
given number of bytes from device. Change ps2_command to
allow using 0 as command ID and actually pass it to the
device instead of working as a drain.
Signed-off-by: Dmitry Torokhov <dtor@mail.ru>
diff --git a/drivers/input/mouse/alps.c b/drivers/input/mouse/alps.c
index 2679a16..ffdc823 100644
--- a/drivers/input/mouse/alps.c
+++ b/drivers/input/mouse/alps.c
@@ -270,7 +270,6 @@
static int alps_passthrough_mode(struct psmouse *psmouse, int enable)
{
struct ps2dev *ps2dev = &psmouse->ps2dev;
- unsigned char param[3];
int cmd = enable ? PSMOUSE_CMD_SETSCALE21 : PSMOUSE_CMD_SETSCALE11;
if (ps2_command(ps2dev, NULL, cmd) ||
@@ -280,7 +279,7 @@
return -1;
/* we may get 3 more bytes, just ignore them */
- ps2_command(ps2dev, param, 0x0300);
+ ps2_drain(ps2dev, 3, 100);
return 0;
}
diff --git a/drivers/input/serio/libps2.c b/drivers/input/serio/libps2.c
index c978657..92b92ee 100644
--- a/drivers/input/serio/libps2.c
+++ b/drivers/input/serio/libps2.c
@@ -29,6 +29,7 @@
EXPORT_SYMBOL(ps2_init);
EXPORT_SYMBOL(ps2_sendbyte);
+EXPORT_SYMBOL(ps2_drain);
EXPORT_SYMBOL(ps2_command);
EXPORT_SYMBOL(ps2_schedule_command);
EXPORT_SYMBOL(ps2_handle_ack);
@@ -45,11 +46,11 @@
/*
- * ps2_sendbyte() sends a byte to the mouse, and waits for acknowledge.
- * It doesn't handle retransmission, though it could - because when there would
- * be need for retransmissions, the mouse has to be replaced anyway.
+ * ps2_sendbyte() sends a byte to the device and waits for acknowledge.
+ * It doesn't handle retransmission, though it could - because if there
+ * is a need for retransmissions device has to be replaced anyway.
*
- * ps2_sendbyte() can only be called from a process context
+ * ps2_sendbyte() can only be called from a process context.
*/
int ps2_sendbyte(struct ps2dev *ps2dev, unsigned char byte, int timeout)
@@ -72,6 +73,31 @@
}
/*
+ * ps2_drain() waits for device to transmit requested number of bytes
+ * and discards them.
+ */
+
+void ps2_drain(struct ps2dev *ps2dev, int maxbytes, int timeout)
+{
+ if (maxbytes > sizeof(ps2dev->cmdbuf)) {
+ WARN_ON(1);
+ maxbytes = sizeof(ps2dev->cmdbuf);
+ }
+
+ down(&ps2dev->cmd_sem);
+
+ serio_pause_rx(ps2dev->serio);
+ ps2dev->flags = PS2_FLAG_CMD;
+ ps2dev->cmdcnt = maxbytes;
+ serio_continue_rx(ps2dev->serio);
+
+ wait_event_timeout(ps2dev->wait,
+ !(ps2dev->flags & PS2_FLAG_CMD),
+ msecs_to_jiffies(timeout));
+ up(&ps2dev->cmd_sem);
+}
+
+/*
* ps2_command() sends a command and its parameters to the mouse,
* then waits for the response and puts it in the param array.
*
@@ -86,6 +112,11 @@
int rc = -1;
int i;
+ if (receive > sizeof(ps2dev->cmdbuf)) {
+ WARN_ON(1);
+ return -1;
+ }
+
down(&ps2dev->cmd_sem);
serio_pause_rx(ps2dev->serio);
@@ -101,10 +132,9 @@
* ACKing the reset command, and so it can take a long
* time before the ACK arrrives.
*/
- if (command & 0xff)
- if (ps2_sendbyte(ps2dev, command & 0xff,
- command == PS2_CMD_RESET_BAT ? 1000 : 200))
- goto out;
+ if (ps2_sendbyte(ps2dev, command & 0xff,
+ command == PS2_CMD_RESET_BAT ? 1000 : 200))
+ goto out;
for (i = 0; i < send; i++)
if (ps2_sendbyte(ps2dev, param[i], 200))
diff --git a/include/linux/libps2.h b/include/linux/libps2.h
index 923bdbc..a710bdd 100644
--- a/include/linux/libps2.h
+++ b/include/linux/libps2.h
@@ -41,6 +41,7 @@
void ps2_init(struct ps2dev *ps2dev, struct serio *serio);
int ps2_sendbyte(struct ps2dev *ps2dev, unsigned char byte, int timeout);
+void ps2_drain(struct ps2dev *ps2dev, int maxbytes, int timeout);
int ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command);
int ps2_schedule_command(struct ps2dev *ps2dev, unsigned char *param, int command);
int ps2_handle_ack(struct ps2dev *ps2dev, unsigned char data);