Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Input: libps2 - rework handling of command response
It is not entirely correct that libps2 sets PS2_FLAG_CMD1 after
the device acknowledges each byte sent to the device by the host.
Rework the code so that PS2_FLAG_CMD1 and PS2_FLAG_CMD are set only once,
at the beginning of PS/2 command execution.
Reviewed-by: Raul E Rangel <rrangel@chromium.org>
Link: https://lore.kernel.org/r/20230511185252.386941-4-dmitry.torokhov@gmail.com
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
+10
-8
+10
-8
drivers/input/serio/libps2.c
+10
-8
drivers/input/serio/libps2.c
···
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serio_pause_rx(ps2dev->serio);
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+
/* Some mice do not ACK the "get ID" command, prepare to handle this. */
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ps2dev->flags = command == PS2_CMD_GETID ? PS2_FLAG_WAITID : 0;
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ps2dev->cmdcnt = receive;
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-
if (receive && param)
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-
for (i = 0; i < receive; i++)
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-
ps2dev->cmdbuf[(receive - 1) - i] = param[i];
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+
if (receive) {
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+
/* Indicate that we expect response to the command. */
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+
ps2dev->flags |= PS2_FLAG_CMD | PS2_FLAG_CMD1;
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+
if (param)
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+
for (i = 0; i < receive; i++)
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+
ps2dev->cmdbuf[(receive - 1) - i] = param[i];
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+
}
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/*
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-
* Some devices (Synaptics) peform the reset before
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+
* Some devices (Synaptics) perform the reset before
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* ACKing the reset command, and so it can take a long
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* time before the ACK arrives.
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*/
···
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return true;
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}
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-
if (!ps2dev->nak) {
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+
if (!ps2dev->nak)
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ps2dev->flags &= ~PS2_FLAG_NAK;
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-
if (ps2dev->cmdcnt)
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-
ps2dev->flags |= PS2_FLAG_CMD | PS2_FLAG_CMD1;
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-
}
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ps2dev->flags &= ~PS2_FLAG_ACK;
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wake_up(&ps2dev->wait);