From c611763d048990de5cdf848d97af6392f8fa7430 Mon Sep 17 00:00:00 2001 From: Dmitry Torokhov Date: Wed, 1 Jun 2005 02:39:51 -0500 Subject: [PATCH] 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 --- drivers/input/mouse/alps.c | 3 +-- drivers/input/serio/libps2.c | 46 +++++++++++++++++++++++++++++------- include/linux/libps2.h | 1 + 3 files changed, 40 insertions(+), 10 deletions(-) diff --git a/drivers/input/mouse/alps.c b/drivers/input/mouse/alps.c index 2679a165d399..ffdc82313192 100644 --- a/drivers/input/mouse/alps.c +++ b/drivers/input/mouse/alps.c @@ -270,7 +270,6 @@ static struct alps_model_info *alps_get_model(struct psmouse *psmouse, int *vers 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 @@ static int alps_passthrough_mode(struct psmouse *psmouse, int enable) 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 c978657068c5..92b92ee03791 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) @@ -71,6 +72,31 @@ 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); + } + + 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)) diff --git a/include/linux/libps2.h b/include/linux/libps2.h index 923bdbc6d9e4..a710bddda4eb 100644 --- a/include/linux/libps2.h +++ b/include/linux/libps2.h @@ -41,6 +41,7 @@ struct ps2dev { 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); -- 2.20.1