We force the FCR contents on many places in the code instead of writing
what was actually set in mxser_change_speed() (by ->activate() or
->set_serial_info()).
So introduce mxser_port::FCR to hold the proper contents and bitwise-OR
the value to what needs to be set on all those locations. That is,
clearing RX and/or TX FIFOs. Those flags are self-clearing, so no need
to set them to mxser_port::FCR.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210922075938.31390-7-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The UART_FCR register is write-only. When reading it, one gets contents
of (read-only) UART_IIR instead as they are shared. This mistake was
performed in mxser_flush_buffer() to clear FIFOs.
Actually FCR handling throughout the driver is completely broken. On
many places, it respects neither mu860 settings, nor FIFO (16450 vs
16550) setting. This patch doesn't help to fix this, it actually does
the same. We will introduce a mxser_port::FCR in the next patch to fix
this issue.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210922075938.31390-6-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Provided FIFO is always enabled for MUST chips, move its FCR setting out
of PORT_8250/PORT_16450 special case in mxser_change_speed(). Now, we
can pre-set fcr to zero and invert the condition of the 'if'.
This makes the code more readable (no functional change intended).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210922075938.31390-4-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
mxser_receive_chars_old() is used whenever MOXA_MUST_LSR_RERR is set in
status no matter the HW ID (the last 'if'). So there is no need for
another check of MOXA_MUST_LSR_RERR _with_ hwid == MOXA_MUST_MU860_HWID
(the third 'if'). Hence remove this subcase. That allows us to check
status on a single line with both UART_LSR_BRK_ERROR_BITS (from the
second 'if') and MOXA_MUST_LSR_RERR (the last 'if').
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210922075938.31390-2-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
If a user tries to set a too high rate, it fails due to check in
mxser_set_baud(). But the high rate remains set in termios, so the user
might think everything went smooth. Restore the baud rate from the
old_termios if this happens, so that user knows nothing was changed in
fact.
It used to behave the correct way many years ago, but somehow the
restoration vanished with commit 1c45607ad3 (Char: mxser, remove it)
-- the commit removed mxser's older clone.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210922075938.31390-1-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Starting and stopping TX is performed on many places in the driver. It
is repeated outb and info->IER modification. Create few helpers
(__mxser_start_tx, mxser_start_tx, __mxser_stop_tx) and use them in the
code instead of open coding.
This should be a base for an uart driver for this device in the future.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210618061516.662-60-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
TX is not supposed to be started from tty_operations::put_char. Line
disciplines ought to call tty_operations::put_char several times and
then do a single tty_operations::flush_chars to start TX.
Fix this in mxser by removing TX startup from mxser_put_char.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210618061516.662-58-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Many boards have only 2 ports. But we always allocate 8 ports (struct
mxser_port) in each struct mxser_board.
Switch this to an empty/variable sized array ([]) and allocate the
needed number of ports using struct_size helper in ->probe.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210618061516.662-54-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There is no need to preallocate an array of four struct mxser_board's.
In most cases a single board or two will be present in a machine. So
allocate struct mxser_board as needed in ->probe.
This makes mxser_boards a bit array. There we store which indexes are
free (unallocated).
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210618061516.662-53-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Rename process_txrx_fifo to mxser_process_txrx_fifo and:
* remove useless parentheses
* return from the 'if's true branch and process the rest in normal code
flow (shift the code one level left)
All this to make the code more readable.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210618061516.662-50-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Again, selecting a bank in the EFR register is duplicated many times.
Extract it to a separate function (mxser_must_select_bank) and use it on
all the places.
This cleans up most of the helpers. And mxser_get_must_hardware_id now
returns the HW ID directly, not via a by-reference parameter.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210618061516.662-42-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
There are multiple copies of setting the EFR register. Separate it to a
new universal function called __mxser_must_set_EFR. And use it in the
code by introducing mxser_must_set_enhance_mode instead of
mxser_disable_must_enchance_mode and mxser_enable_must_enchance_mode.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210618061516.662-41-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
The MXSER_PORTS's tty_device is never registered and neither its
tty_port instance exists. Hence, it's quite pointless to allocate it.
It used to be used for global information fetches via ioctls. We have
just removed these as non-existent tty_device+tty_port was exactly the
reason to remove the ioctls.
It would be peculiar to add this "virtual" port as we require a backing
tty_port since commit ecbbfd44a0 (TTY: move tty buffers to tty_port)
in 2012.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210618061516.662-33-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1) The semantics are defined exactly nowhere.
2) The ioctl definition was never exposed to userspace, so noone should
actually be reliably using this.
3) It's not even mentioned in any of the mxser utilities.
Provided the above, remove this mxser-special ioctl.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210618061516.662-31-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1) The semantics are defined exactly nowhere.
2) The ioctl definition was never exposed to userspace, so noone should
actually be reliably using this.
3) It's not even mentioned in any of the mxser utilities.
Provided the above, remove this mxser-special ioctl.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210618061516.662-30-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1) MOXA_GETMSTATUS is broken at least since commit ecbbfd44a0 (TTY:
move tty buffers to tty_port) in 2012.
Even though it's mentioned in the mon_pa moxa utility, obviously
noone ever tried that in that timeframe.
2) The ioctl definition was never exposed to userspace, so noone
should actually be reliably using this.
Provided the above, remove this mxser-special ioctl.
And remove the whole concept of mxser_ioctl_special as this was the last
ioctl in there.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210618061516.662-29-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
1) MOXA_GETDATACOUNT is broken at least since commit ecbbfd44a0 (TTY:
move tty buffers to tty_port) in 2012.
Even though it's mentioned in the mon_p moxa utility, obviously noone
ever tried that in that timeframe.
2) The ioctl definition was never exposed to userspace, so noone should
actually be reliably using this.
Provided the above, remove this mxser-special ioctl.
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Link: https://lore.kernel.org/r/20210618061516.662-28-jslaby@suse.cz
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>