| Message ID | 20230511185252.386941-4-dmitry.torokhov@gmail.com |
|---|---|
| State | Accepted |
| Commit | df9fe0e653c28756ab98f58175f8c58baf156ef1 |
| Headers | show |
| Series | libps2: be more tolerant when processing commands | expand |
On Thu, May 11, 2023 at 11:52:43AM -0700, Dmitry Torokhov wrote: > 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. > > Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> > --- > drivers/input/serio/libps2.c | 18 ++++++++++-------- > 1 file changed, 10 insertions(+), 8 deletions(-) > > diff --git a/drivers/input/serio/libps2.c b/drivers/input/serio/libps2.c > index 399cda0d34f5..d09450eca9a7 100644 > --- a/drivers/input/serio/libps2.c > +++ b/drivers/input/serio/libps2.c > @@ -247,14 +247,19 @@ int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command) > > serio_pause_rx(ps2dev->serio); > > + /* Some mice do not ACK the "get ID" command, prepare to handle this. */ > ps2dev->flags = command == PS2_CMD_GETID ? PS2_FLAG_WAITID : 0; > ps2dev->cmdcnt = receive; > - if (receive && param) > - for (i = 0; i < receive; i++) > - ps2dev->cmdbuf[(receive - 1) - i] = param[i]; > + if (receive) { > + /* Indicate that we expect response to the command. */ > + ps2dev->flags |= PS2_FLAG_CMD | PS2_FLAG_CMD1; > + if (param) > + for (i = 0; i < receive; i++) > + ps2dev->cmdbuf[(receive - 1) - i] = param[i]; > + } > > /* > - * Some devices (Synaptics) peform the reset before > + * Some devices (Synaptics) perform the reset before > * ACKing the reset command, and so it can take a long > * time before the ACK arrives. > */ > @@ -434,11 +439,8 @@ bool ps2_handle_ack(struct ps2dev *ps2dev, u8 data) > return true; > } > > - if (!ps2dev->nak) { > + if (!ps2dev->nak) > ps2dev->flags &= ~PS2_FLAG_NAK; > - if (ps2dev->cmdcnt) > - ps2dev->flags |= PS2_FLAG_CMD | PS2_FLAG_CMD1; > - } > > ps2dev->flags &= ~PS2_FLAG_ACK; > wake_up(&ps2dev->wait); Reviewed-by: Raul E Rangel <rrangel@chromium.org>
diff --git a/drivers/input/serio/libps2.c b/drivers/input/serio/libps2.c index 399cda0d34f5..d09450eca9a7 100644 --- a/drivers/input/serio/libps2.c +++ b/drivers/input/serio/libps2.c @@ -247,14 +247,19 @@ int __ps2_command(struct ps2dev *ps2dev, u8 *param, unsigned int command) serio_pause_rx(ps2dev->serio); + /* Some mice do not ACK the "get ID" command, prepare to handle this. */ ps2dev->flags = command == PS2_CMD_GETID ? PS2_FLAG_WAITID : 0; ps2dev->cmdcnt = receive; - if (receive && param) - for (i = 0; i < receive; i++) - ps2dev->cmdbuf[(receive - 1) - i] = param[i]; + if (receive) { + /* Indicate that we expect response to the command. */ + ps2dev->flags |= PS2_FLAG_CMD | PS2_FLAG_CMD1; + if (param) + for (i = 0; i < receive; i++) + ps2dev->cmdbuf[(receive - 1) - i] = param[i]; + } /* - * Some devices (Synaptics) peform the reset before + * Some devices (Synaptics) perform the reset before * ACKing the reset command, and so it can take a long * time before the ACK arrives. */ @@ -434,11 +439,8 @@ bool ps2_handle_ack(struct ps2dev *ps2dev, u8 data) return true; } - if (!ps2dev->nak) { + if (!ps2dev->nak) ps2dev->flags &= ~PS2_FLAG_NAK; - if (ps2dev->cmdcnt) - ps2dev->flags |= PS2_FLAG_CMD | PS2_FLAG_CMD1; - } ps2dev->flags &= ~PS2_FLAG_ACK; wake_up(&ps2dev->wait);
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. Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> --- drivers/input/serio/libps2.c | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-)