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);
/*
- * 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)
return -ps2dev->nak;
}
+/*
+ * 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);
+ }
+
+ mutex_lock(&ps2dev->cmd_mutex);
+
+ 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));
+ mutex_unlock(&ps2dev->cmd_mutex);
+}
+
+/*
+ * ps2_is_keyboard_id() checks received ID byte against the list of
+ * known keyboard IDs.
+ */
+
+static inline int ps2_is_keyboard_id(char id_byte)
+{
+ static char keyboard_ids[] = {
+ 0xab, /* Regular keyboards */
+ 0xac, /* NCD Sun keyboard */
+ 0x2b, /* Trust keyboard, translated */
+ 0x5d, /* Trust keyboard */
+ 0x60, /* NMB SGI keyboard, translated */
+ 0x47, /* NMB SGI keyboard */
+ };
+
+ return memchr(keyboard_ids, id_byte, sizeof(keyboard_ids)) != NULL;
+}
+
+/*
+ * ps2_adjust_timeout() is called after receiving 1st byte of command
+ * response and tries to reduce remaining timeout to speed up command
+ * completion.
+ */
+
+static int ps2_adjust_timeout(struct ps2dev *ps2dev, int command, int timeout)
+{
+ switch (command) {
+ case PS2_CMD_RESET_BAT:
+ /*
+ * Device has sent the first response byte after
+ * reset command, reset is thus done, so we can
+ * shorten the timeout.
+ * The next byte will come soon (keyboard) or not
+ * at all (mouse).
+ */
+ if (timeout > msecs_to_jiffies(100))
+ timeout = msecs_to_jiffies(100);
+ break;
+
+ case PS2_CMD_GETID:
+ /*
+ * If device behind the port is not a keyboard there
+ * won't be 2nd byte of ID response.
+ */
+ if (!ps2_is_keyboard_id(ps2dev->cmdbuf[1])) {
+ serio_pause_rx(ps2dev->serio);
+ ps2dev->flags = ps2dev->cmdcnt = 0;
+ serio_continue_rx(ps2dev->serio);
+ timeout = 0;
+ }
+ break;
+
+ default:
+ break;
+ }
+
+ return timeout;
+}
+
/*
* ps2_command() sends a command and its parameters to the mouse,
* then waits for the response and puts it in the param array.
int rc = -1;
int i;
- down(&ps2dev->cmd_sem);
+ if (receive > sizeof(ps2dev->cmdbuf)) {
+ WARN_ON(1);
+ return -1;
+ }
+
+ mutex_lock(&ps2dev->cmd_mutex);
serio_pause_rx(ps2dev->serio);
ps2dev->flags = command == PS2_CMD_GETID ? PS2_FLAG_WAITID : 0;
* 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))
if (ps2dev->cmdcnt && timeout > 0) {
- if (command == PS2_CMD_RESET_BAT && timeout > msecs_to_jiffies(100)) {
- /*
- * Device has sent the first response byte
- * after a reset command, reset is thus done,
- * shorten the timeout. The next byte will come
- * soon (keyboard) or not at all (mouse).
- */
- timeout = msecs_to_jiffies(100);
- }
-
- if (command == PS2_CMD_GETID &&
- ps2dev->cmdbuf[receive - 1] != 0xab && /* Regular keyboards */
- ps2dev->cmdbuf[receive - 1] != 0xac && /* NCD Sun keyboard */
- ps2dev->cmdbuf[receive - 1] != 0x2b && /* Trust keyboard, translated */
- ps2dev->cmdbuf[receive - 1] != 0x5d && /* Trust keyboard */
- ps2dev->cmdbuf[receive - 1] != 0x60 && /* NMB SGI keyboard, translated */
- ps2dev->cmdbuf[receive - 1] != 0x47) { /* NMB SGI keyboard */
- /*
- * Device behind the port is not a keyboard
- * so we don't need to wait for the 2nd byte
- * of ID response.
- */
- serio_pause_rx(ps2dev->serio);
- ps2dev->flags = ps2dev->cmdcnt = 0;
- serio_continue_rx(ps2dev->serio);
- }
-
+ timeout = ps2_adjust_timeout(ps2dev, command, timeout);
wait_event_timeout(ps2dev->wait,
!(ps2dev->flags & PS2_FLAG_CMD), timeout);
}
rc = 0;
-out:
+ out:
serio_pause_rx(ps2dev->serio);
ps2dev->flags = 0;
serio_continue_rx(ps2dev->serio);
- up(&ps2dev->cmd_sem);
+ mutex_unlock(&ps2dev->cmd_mutex);
return rc;
}
void ps2_init(struct ps2dev *ps2dev, struct serio *serio)
{
- init_MUTEX(&ps2dev->cmd_sem);
+ mutex_init(&ps2dev->cmd_mutex);
init_waitqueue_head(&ps2dev->wait);
ps2dev->serio = serio;
}
git://git.onelab.eu / linux-2.6.git / blobdiff