H Ulrik, On Sun, Jan 21, 2018 at 09:22:31PM +0100, [email protected] wrote: > > Hi, > > the patch series looks nice, but best to also include the procedure > described here in Documentation/input somewhere. I would not expect > everyone to dig into git commit logs to find the howto :)
Right now we do not have any notes in kernel on debugging PS/2 devices, although we have a bunch of tools (ps2emu), etc. I wonder if I can get Benjamin or Lyude or Hans or Peter write something up as they've been doing a lot of touchpad bringups... Thanks. > > Best regards, > Ulrik > > > On Fri, Jan 19, 2018 at 11:41:09AM -0800, Dmitry Torokhov wrote: > > Date: Fri, 19 Jan 2018 11:41:09 -0800 > > From: Dmitry Torokhov <[email protected]> > > To: Benjamin Tissoires <[email protected]>, Hans de Goede > > <[email protected]>, Lyude Paul <[email protected]> > > Cc: [email protected], [email protected] > > Subject: [PATCH 5/7] Input: libps2 - add debugging statements > > X-Mailer: git-send-email 2.16.0.rc1.238.g530d649a79-goog > > X-Mailing-List: [email protected] > > > > Debugging via i8042.debug and analyzing raw PS/2 data stream may be > > cumbersome as you need to locate the boundaries of commands, decipher the > > sliced commands, etc, etc. Let's add a bit more high level debug statements > > for ps2_sendbyte(), ps2_command(), and ps2_sliced_command(). > > > > We do not introduce a new module parameter, but rater rely on the kernel > > having dynamic debug facility enabled (which most everyone has nowadays). > > Enable with: > > > > echo "file libps2.c +pf" > /sys/kernel/debug/dynamic_debug/control > > > > or add "libps2.dyndbg=+pf" to the kernel command line. > > > > Signed-off-by: Dmitry Torokhov <[email protected]> > > --- > > drivers/input/serio/libps2.c | 52 > > +++++++++++++++++++++++++++++++++----------- > > 1 file changed, 39 insertions(+), 13 deletions(-) > > > > diff --git a/drivers/input/serio/libps2.c b/drivers/input/serio/libps2.c > > index e96ae477f0b56..82befae4dab04 100644 > > --- a/drivers/input/serio/libps2.c > > +++ b/drivers/input/serio/libps2.c > > @@ -26,22 +26,20 @@ MODULE_AUTHOR("Dmitry Torokhov <[email protected]>"); > > MODULE_DESCRIPTION("PS/2 driver library"); > > MODULE_LICENSE("GPL"); > > > > -/* > > - * 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. > > - */ > > - > > -int ps2_sendbyte(struct ps2dev *ps2dev, u8 byte, unsigned int timeout) > > +static int ps2_do_sendbyte(struct ps2dev *ps2dev, u8 byte, unsigned int > > timeout) > > { > > + int error; > > + > > serio_pause_rx(ps2dev->serio); > > ps2dev->nak = 1; > > ps2dev->flags |= PS2_FLAG_ACK; > > serio_continue_rx(ps2dev->serio); > > > > - if (serio_write(ps2dev->serio, byte) == 0) > > + error = serio_write(ps2dev->serio, byte); > > + if (error) > > + dev_dbg(&ps2dev->serio->dev, > > + "failed to write %#02x: %d\n", byte, error); > > + else > > wait_event_timeout(ps2dev->wait, > > !(ps2dev->flags & PS2_FLAG_ACK), > > msecs_to_jiffies(timeout)); > > @@ -52,6 +50,24 @@ int ps2_sendbyte(struct ps2dev *ps2dev, u8 byte, > > unsigned int timeout) > > > > return -ps2dev->nak; > > } > > + > > +/* > > + * 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. > > + */ > > + > > +int ps2_sendbyte(struct ps2dev *ps2dev, u8 byte, unsigned int timeout) > > +{ > > + int retval; > > + > > + retval = ps2_do_sendbyte(ps2dev, byte, timeout); > > + dev_dbg(&ps2dev->serio->dev, "%02x - %x\n", byte, ps2dev->nak); > > + > > + return retval; > > +} > > EXPORT_SYMBOL(ps2_sendbyte); > > > > void ps2_begin_command(struct ps2dev *ps2dev) > > @@ -186,6 +202,7 @@ int __ps2_command(struct ps2dev *ps2dev, u8 *param, > > unsigned int command) > > unsigned int receive = (command >> 8) & 0xf; > > int rc = -1; > > int i; > > + u8 send_param[16]; > > > > if (receive > sizeof(ps2dev->cmdbuf)) { > > WARN_ON(1); > > @@ -197,6 +214,8 @@ int __ps2_command(struct ps2dev *ps2dev, u8 *param, > > unsigned int command) > > return -1; > > } > > > > + memcpy(send_param, param, send); > > + > > serio_pause_rx(ps2dev->serio); > > ps2dev->flags = command == PS2_CMD_GETID ? PS2_FLAG_WAITID : 0; > > ps2dev->cmdcnt = receive; > > @@ -210,14 +229,14 @@ int __ps2_command(struct ps2dev *ps2dev, u8 *param, > > unsigned int command) > > * ACKing the reset command, and so it can take a long > > * time before the ACK arrives. > > */ > > - if (ps2_sendbyte(ps2dev, command & 0xff, > > - command == PS2_CMD_RESET_BAT ? 1000 : 200)) { > > + if (ps2_do_sendbyte(ps2dev, command & 0xff, > > + command == PS2_CMD_RESET_BAT ? 1000 : 200)) { > > serio_pause_rx(ps2dev->serio); > > goto out_reset_flags; > > } > > > > for (i = 0; i < send; i++) { > > - if (ps2_sendbyte(ps2dev, param[i], 200)) { > > + if (ps2_do_sendbyte(ps2dev, param[i], 200)) { > > serio_pause_rx(ps2dev->serio); > > goto out_reset_flags; > > } > > @@ -253,6 +272,12 @@ int __ps2_command(struct ps2dev *ps2dev, u8 *param, > > unsigned int command) > > ps2dev->flags = 0; > > serio_continue_rx(ps2dev->serio); > > > > + dev_dbg(&ps2dev->serio->dev, > > + "%02x [%*ph] - %x/%08lx [%*ph]\n", > > + command & 0xff, send, send_param, > > + ps2dev->nak, ps2dev->flags, > > + receive, param ?: send_param); > > + > > return rc; > > } > > EXPORT_SYMBOL(__ps2_command); > > @@ -296,6 +321,7 @@ int ps2_sliced_command(struct ps2dev *ps2dev, u8 > > command) > > } > > > > out: > > + dev_dbg(&ps2dev->serio->dev, "%02x - %d\n", command, retval); > > ps2_end_command(ps2dev); > > return retval; > > } > > -- > > 2.16.0.rc1.238.g530d649a79-goog > > > > -- > > To unsubscribe from this list: send the line "unsubscribe linux-input" in > > the body of a message to [email protected] > > More majordomo info at http://vger.kernel.org/majordomo-info.html -- Dmitry
