linux-stable.git/drivers/tty/serial, branch v3.16.78

tty: serial: cpm_uart - fix init when SMC is relocated

2019-10-31T22:14:50+00:00

commit 06aaa3d066db87e8478522d910285141d44b1e58 upstream.

SMC relocation can also be activated earlier by the bootloader,
so the driver's behaviour cannot rely on selected kernel config.

When the SMC is relocated, CPM_CR_INIT_TRX cannot be used.

But the only thing CPM_CR_INIT_TRX does is to clear the
rstate and tstate registers, so this can be done manually,
even when SMC is not relocated.

Signed-off-by: Christophe Leroy 
Fixes: 9ab921201444 ("cpm_uart: fix non-console port startup bug")
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

tty: max310x: Fix external crystal register setup

2019-10-05T15:19:41+00:00

commit 5d24f455c182d5116dd5db8e1dc501115ecc9c2c upstream.

The datasheet states:

  Bit 4: ClockEnSet the ClockEn bit high to enable an external clocking
(crystal or clock generator at XIN). Set the ClockEn bit to 0 to disable
clocking
  Bit 1: CrystalEnSet the CrystalEn bit high to enable the crystal
oscillator. When using an external clock source at XIN, CrystalEn must
be set low.

The bit 4, MAX310X_CLKSRC_EXTCLK_BIT, should be set and was not.

This was required to make the MAX3107 with an external crystal on our
board able to send or receive data.

Signed-off-by: Joe Burmeister 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

serial: sh-sci: disable DMA for uart_console

2019-10-05T15:19:40+00:00

commit 099506cbbc79c0bd52b19cb6b930f256dabc3950 upstream.

As noted in commit 84b40e3b57ee ("serial: 8250: omap: Disable DMA for
console UART"), UART console lines use low-level PIO only access functions
which will conflict with use of the line when DMA is enabled, e.g. when
the console line is also used for systemd messages. So disable DMA
support for UART console lines.

Reported-by: Michael Rodin 
Link: https://patchwork.kernel.org/patch/10929511/
Tested-by: Eugeniu Rosca 
Reviewed-by: Simon Horman 
Reviewed-by: Wolfram Sang 
Reviewed-by: Geert Uytterhoeven 
Signed-off-by: George G. Davis 
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings

TTY: serial_core, add ->install

2019-09-23T20:11:50+00:00

commit 4cdd17ba1dff20ffc99fdbd2e6f0201fc7fe67df upstream.

We need to compute the uart state only on the first open. This is
usually what is done in the ->install hook. serial_core used to do this
in ->open on every open. So move it to ->install.

As a side effect, it ensures the state is set properly in the window
after tty_init_dev is called, but before uart_open. This fixes a bunch
of races between tty_open and flush_to_ldisc we were dealing with
recently.

One of such bugs was attempted to fix in commit fedb5760648a (serial:
fix race between flush_to_ldisc and tty_open), but it only took care of
a couple of functions (uart_start and uart_unthrottle).  I was able to
reproduce the crash on a SLE system, but in uart_write_room which is
also called from flush_to_ldisc via process_echoes. I was *unable* to
reproduce the bug locally. It is due to having this patch in my queue
since 2012!

 general protection fault: 0000 [#1] SMP KASAN PTI
 CPU: 1 PID: 5 Comm: kworker/u4:0 Tainted: G             L 4.12.14-396-default #1 SLE15-SP1 (unreleased)
 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.12.0-0-ga698c89-prebuilt.qemu.org 04/01/2014
 Workqueue: events_unbound flush_to_ldisc
 task: ffff8800427d8040 task.stack: ffff8800427f0000
 RIP: 0010:uart_write_room+0xc4/0x590
 RSP: 0018:ffff8800427f7088 EFLAGS: 00010202
 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: 0000000000000000
 RDX: 000000000000002f RSI: 00000000000000ee RDI: ffff88003888bd90
 RBP: ffffffffb9545850 R08: 0000000000000001 R09: 0000000000000400
 R10: ffff8800427d825c R11: 000000000000006e R12: 1ffff100084fee12
 R13: ffffc900004c5000 R14: ffff88003888bb28 R15: 0000000000000178
 FS:  0000000000000000(0000) GS:ffff880043300000(0000) knlGS:0000000000000000
 CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 CR2: 0000561da0794148 CR3: 000000000ebf4000 CR4: 00000000000006e0
 Call Trace:
  tty_write_room+0x6d/0xc0
  __process_echoes+0x55/0x870
  n_tty_receive_buf_common+0x105e/0x26d0
  tty_ldisc_receive_buf+0xb7/0x1c0
  tty_port_default_receive_buf+0x107/0x180
  flush_to_ldisc+0x35d/0x5c0
...

0 in rbx means tty->driver_data is NULL in uart_write_room. 0x178 is
tried to be dereferenced (0x178 >> 3 is 0x2f in rdx) at
uart_write_room+0xc4. 0x178 is exactly (struct uart_state *)NULL->refcount
used in uart_port_lock from uart_write_room.

So revert the upstream commit here as my local patch should fix the
whole family.

Signed-off-by: Jiri Slaby 
Cc: Li RongQing 
Cc: Wang Li 
Cc: Zhang Yu 
Cc: Greg Kroah-Hartman 
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 3.16: The previous fix didn't apply, so we don't need
 to revert it here.]
Signed-off-by: Ben Hutchings

serial: sh-sci: Fix setting SCSCR_TIE while transferring data

2019-08-13T11:38:47+00:00

commit 93bcefd4c6bad4c69dbc4edcd3fbf774b24d930d upstream.

We disable transmission interrupt (clear SCSCR_TIE) after all data has been transmitted
(if uart_circ_empty(xmit)). While transmitting, if the data is still in the tty buffer,
re-enable the SCSCR_TIE bit, which was done at sci_start_tx().
This is unnecessary processing, wasting CPU operation if the data transmission length is large.
And further, transmit end, FIFO empty bits disabling have also been performed in the step above.

Signed-off-by: Hoan Nguyen An 
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings

tty: mxs-auart: fix a potential NULL pointer dereference

2019-08-13T11:38:47+00:00

commit 6734330654dac550f12e932996b868c6d0dcb421 upstream.

In case ioremap fails, the fix returns -ENOMEM to avoid NULL
pointer dereferences.
Multiple places use port.membase.

Signed-off-by: Kangjie Lu 
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 3.16: There is no out_disable_clks label, so goto
 out_free_clk on error]
Signed-off-by: Ben Hutchings

tty: atmel_serial: fix a potential NULL pointer dereference

2019-08-13T11:38:46+00:00

commit c85be041065c0be8bc48eda4c45e0319caf1d0e5 upstream.

In case dmaengine_prep_dma_cyclic fails, the fix returns a proper
error code to avoid NULL pointer dereference.

Signed-off-by: Kangjie Lu 
Fixes: 34df42f59a60 ("serial: at91: add rx dma support")
Acked-by: Richard Genoud 
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 3.16: adjust context]
Signed-off-by: Ben Hutchings

serial: max310x: Fix to avoid potential NULL pointer dereference

2019-08-13T11:38:46+00:00

commit 3a10e3dd52e80b9a97a3346020024d17b2c272d6 upstream.

of_match_device can return a NULL pointer when matching device is not
found. This patch avoids a scenario causing NULL pointer derefernce.

Signed-off-by: Aditya Pakki 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings

serial: 8250_of: assume reg-shift of 2 for mrvl,mmp-uart

2019-07-09T21:04:08+00:00

commit f4817843e39ce78aace0195a57d4e8500a65a898 upstream.

There are two other drivers that bind to mrvl,mmp-uart and both of them
assume register shift of 2 bits. There are device trees that lack the
property and rely on that assumption.

If this driver wins the race to bind to those devices, it should behave
the same as the older deprecated driver.

Signed-off-by: Lubomir Rintel 
Signed-off-by: Greg Kroah-Hartman 
[bwh: Backported to 3.16: adjust filename]
Signed-off-by: Ben Hutchings

serial: 8250_pci: Have ACCES cards that use the four port Pericom PI7C9X7954 chip use the pci_pericom_setup()

2019-07-09T21:04:01+00:00

commit 78d3820b9bd39028727c6aab7297b63c093db343 upstream.

The four port Pericom chips have the fourth port at the wrong address.
Make use of quirk to fix it.

Fixes: c8d192428f52 ("serial: 8250: added acces i/o products quad and octal serial cards")
Signed-off-by: Jay Dolan 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Ben Hutchings