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path: root/drivers/input/serio/libps2.c
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Diffstat (limited to 'drivers/input/serio/libps2.c')
-rw-r--r--drivers/input/serio/libps2.c46
1 files changed, 38 insertions, 8 deletions
diff --git a/drivers/input/serio/libps2.c b/drivers/input/serio/libps2.c
index c978657068c..92b92ee0379 100644
--- a/drivers/input/serio/libps2.c
+++ b/drivers/input/serio/libps2.c
@@ -29,6 +29,7 @@ MODULE_LICENSE("GPL");
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 @@ struct ps2work {
/*
- * 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 @@ int ps2_sendbyte(struct ps2dev *ps2dev, unsigned char byte, int timeout)
}
/*
+ * 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 ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command)
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 @@ int ps2_command(struct ps2dev *ps2dev, unsigned char *param, int command)
* 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))