linux-stable.git/drivers/tty/serial/8250, branch linux-4.18.y

Revert "serial: 8250_dw: Fix runtime PM handling"

2018-11-04T13:51:47+00:00

[ Upstream commit beeeac43b6fae5f5eaf707b6fcc2bf1e09deb785 ]

This reverts commit d76c74387e1c978b6c5524a146ab0f3f72206f98.

While commit d76c74387e1c ("serial: 8250_dw: Fix runtime PM handling")
fixes runtime PM handling when using kgdb, it introduces a traceback for
everyone else.

BUG: sleeping function called from invalid context at
	/mnt/host/source/src/third_party/kernel/next/drivers/base/power/runtime.c:1034
in_atomic(): 1, irqs_disabled(): 1, pid: 1, name: swapper/0
7 locks held by swapper/0/1:
 #0: 000000005ec5bc72 (&dev->mutex){....}, at: __driver_attach+0xb5/0x12b
 #1: 000000005d5fa9e5 (&dev->mutex){....}, at: __device_attach+0x3e/0x15b
 #2: 0000000047e93286 (serial_mutex){+.+.}, at: serial8250_register_8250_port+0x51/0x8bb
 #3: 000000003b328f07 (port_mutex){+.+.}, at: uart_add_one_port+0xab/0x8b0
 #4: 00000000fa313d4d (&port->mutex){+.+.}, at: uart_add_one_port+0xcc/0x8b0
 #5: 00000000090983ca (console_lock){+.+.}, at: vprintk_emit+0xdb/0x217
 #6: 00000000c743e583 (console_owner){-...}, at: console_unlock+0x211/0x60f
irq event stamp: 735222
__down_trylock_console_sem+0x4a/0x84
console_unlock+0x338/0x60f
__do_softirq+0x4a4/0x50d
irq_exit+0x64/0xe2
CPU: 2 PID: 1 Comm: swapper/0 Not tainted 4.19.0-rc5 #6
Hardware name: Google Caroline/Caroline, BIOS Google_Caroline.7820.286.0 03/15/2017
Call Trace:
 dump_stack+0x7d/0xbd
 ___might_sleep+0x238/0x259
 __pm_runtime_resume+0x4e/0xa4
 ? serial8250_rpm_get+0x2e/0x44
 serial8250_console_write+0x44/0x301
 ? lock_acquire+0x1b8/0x1fa
 console_unlock+0x577/0x60f
 vprintk_emit+0x1f0/0x217
 printk+0x52/0x6e
 register_console+0x43b/0x524
 uart_add_one_port+0x672/0x8b0
 ? set_io_from_upio+0x150/0x162
 serial8250_register_8250_port+0x825/0x8bb
 dw8250_probe+0x80c/0x8b0
 ? dw8250_serial_inq+0x8e/0x8e
 ? dw8250_check_lcr+0x108/0x108
 ? dw8250_runtime_resume+0x5b/0x5b
 ? dw8250_serial_outq+0xa1/0xa1
 ? dw8250_remove+0x115/0x115
 platform_drv_probe+0x76/0xc5
 really_probe+0x1f1/0x3ee
 ? driver_allows_async_probing+0x5d/0x5d
 driver_probe_device+0xd6/0x112
 ? driver_allows_async_probing+0x5d/0x5d
 bus_for_each_drv+0xbe/0xe5
 __device_attach+0xdd/0x15b
 bus_probe_device+0x5a/0x10b
 device_add+0x501/0x894
 ? _raw_write_unlock+0x27/0x3a
 platform_device_add+0x224/0x2b7
 mfd_add_device+0x718/0x75b
 ? __kmalloc+0x144/0x16a
 ? mfd_add_devices+0x38/0xdb
 mfd_add_devices+0x9b/0xdb
 intel_lpss_probe+0x7d4/0x8ee
 intel_lpss_pci_probe+0xac/0xd4
 pci_device_probe+0x101/0x18e
...

Revert the offending patch until a more comprehensive solution
is available.

Cc: Tony Lindgren 
Cc: Andy Shevchenko 
Cc: Phil Edworthy 
Fixes: d76c74387e1c ("serial: 8250_dw: Fix runtime PM handling")
Signed-off-by: Guenter Roeck 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin

drivers/tty: add error handling for pcmcia_loop_config

2018-10-03T23:59:11+00:00

[ Upstream commit 85c634e919bd6ef17427f26a52920aeba12e16ee ]

When pcmcia_loop_config fails, the lack of error-handling code may
cause unexpected results.

This patch adds error-handling code after calling pcmcia_loop_config.

Signed-off-by: Zhouyang Jia 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

serial: 8250: of: Correct of_platform_serial_setup() error handling

2018-09-26T06:39:38+00:00

[ Upstream commit b29330d829042512fabb2bfa3bbfa32df1115594 ]

Don't dispose IRQ mapping before it has been created.

Fixes: aa9594740 ("serial: 8250_of: Add IO space support")
Signed-off-by: Alexander Sverdlin 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Sasha Levin 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_dw: Add ACPI support for uart on Broadcom SoC

2018-08-22T05:43:43+00:00

commit 784c29eda5b4e28c3a56aa90b3815f9a1b0cfdc1 upstream.

Add ACPI identifier HID for UART DW 8250 on Broadcom SoCs
to match the HID passed through ACPI tables to enable
UART controller.

Signed-off-by: Srinath Mannam 
Reviewed-by: Vladimir Olovyannikov 
Tested-by: Vladimir Olovyannikov 
Reviewed-by: Andy Shevchenko 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_dw: always set baud rate in dw8250_set_termios

2018-08-22T05:43:42+00:00

commit dfcab6ba573445c703235ab6c83758eec12d7f28 upstream.

dw8250_set_termios() doesn't set baud rate if the arg "old ktermios" is
NULL. This happens during resume.
Call Trace:
...
[   54.928108] dw8250_set_termios+0x162/0x170
[   54.928114] serial8250_set_termios+0x17/0x20
[   54.928117] uart_change_speed+0x64/0x160
[   54.928119] uart_resume_port
...

So the baud rate is not restored after S3 and breaks the apps who use
UART, for example, console and bluetooth etc.

We address this issue by setting the baud rate irrespective of arg
"old", just like the drivers for other 8250 IPs. This is tested with
Intel Broxton platform.

Signed-off-by: Chen Hu 
Fixes: 4e26b134bd17 ("serial: 8250_dw: clock rate handling for all ACPI platforms")
Cc: Heikki Krogerus 
Cc: stable 
Reviewed-by: Andy Shevchenko 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_exar: Read INT0 from slave device, too

2018-08-22T05:43:42+00:00

commit 60ab0fafc4b652fcaf7cbc3bb8555a0cf1149c28 upstream.

The sleep wake-up refactoring that I introduced in

  commit c7e1b4059075 ("tty: serial: exar: Relocate sleep wake-up handling")

did not account for devices with a slave device on the expansion port.
This patch pokes the INT0 register in the slave device, if present, in
order to ensure that MSI interrupts don't get permanently "stuck"
because of a sleep wake-up interrupt as described here:

  commit 2c0ac5b48a35 ("serial: exar: Fix stuck MSIs")

This also converts an ioread8() to readb() in order to provide visual
consistency with the MMIO-only accessors used elsewhere in the driver.

Reported-by: Andy Shevchenko 
Signed-off-by: Aaron Sierra 
Fixes: c7e1b4059075 ("tty: serial: exar: Relocate sleep wake-up handling")
Reviewed-by: Andy Shevchenko 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

tty: serial: 8250: Revert NXP SC16C2552 workaround

2018-08-22T05:43:42+00:00

commit 47ac76662ca9c5852fd353093f19de3ae85f2e66 upstream.

Revert commit ecb988a3b7985913d1f0112f66667cdd15e40711: tty: serial:
8250: 8250_core: NXP SC16C2552 workaround

The above commit causes userland application to no longer write
correctly its first write to a dumb terminal connected to /dev/ttyS0.
This commit seems to be the culprit. It's as though the TX FIFO is being
reset during that write. What should be displayed is:

PSW 80000000 INST 00000000                           HALT
//

What is displayed is some variation of:

T 00000000           HAL//

Reverting this commit via this patch fixes my problem.

Signed-off-by: Mark Hounschell 
Fixes: ecb988a3b798 ("tty: serial: 8250: 8250_core: NXP SC16C2552 workaround")
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_pci: Remove stalled entries in blacklist

2018-06-28T12:34:39+00:00

After the commit

  7d8905d06405 ("serial: 8250_pci: Enable device after we check black list")

pure serial multi-port cards, such as CH355, got blacklisted and thus
not being enumerated anymore. Previously, it seems, blacklisting them
was on purpose to shut up pciserial_init_one() about record duplication.

So, remove the entries from blacklist in order to get cards enumerated.

Fixes: 7d8905d06405 ("serial: 8250_pci: Enable device after we check black list")
Reported-by: Matt Turner 
Cc: Sergej Pupykin 
Cc: Alexandr Petrenko 
Signed-off-by: Andy Shevchenko 
Reviewed-and-Tested-by: Matt Turner 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman

serial: 8250_dw: Fix runtime PM handling

2018-05-14T11:51:12+00:00

When using kgdb, you get an abort when accessing the UART registers.
This is because the driver has already entered runtime PM and so turned
off the bus clock needed to access the registers.

To fix this, set the capability indicating Runtime PM is active while idle.

Signed-off-by: Phil Edworthy 
Signed-off-by: Greg Kroah-Hartman

serial: 8250: omap: Fix idling of clocks for unused uarts

2018-05-14T11:51:12+00:00

I noticed that unused UARTs won't necessarily idle properly always
unless at least one byte tx transfer is done first.

After some debugging I narrowed down the problem to the scr register
dma configuration bits that need to be set before softreset for the
clocks to idle. Unless we do this, the module clkctrl idlest bits
may be set to 1 instead of 3 meaning the clock will never idle and
is blocking deeper idle states for the whole domain.

This might be related to the configuration done by the bootloader
or kexec booting where certain configurations cause the 8250 or
the clkctrl clock to jam in a way where setting of the scr bits
and reset is needed to clear it. I've tried diffing the 8250
registers for the various modes, but did not see anything specific.
So far I've only seen this on omap4 but I'm suspecting this might
also happen on the other clkctrl using SoCs considering they
already have a quirk enabled for UART_ERRATA_CLOCK_DISABLE.

Let's fix the issue by configuring scr before reset for basic dma
even if we don't use it. The scr register will be reset when we do
softreset few lines after, and we restore scr on resume. We should
do this for all the SoCs with UART_ERRATA_CLOCK_DISABLE quirk flag
set since the ones with UART_ERRATA_CLOCK_DISABLE are all based
using clkctrl similar to omap4.

Looks like both OMAP_UART_SCR_DMAMODE_1 | OMAP_UART_SCR_DMAMODE_CTL
bits are needed for the clkctrl to idle after a softreset.

And we need to add omap4 to also use the UART_ERRATA_CLOCK_DISABLE
for the related workaround to be enabled. This same compatible
value will also be used for omap5.

Fixes: cdb929e4452a ("serial: 8250_omap: workaround errata around idling UART after using DMA")
Cc: Keerthy 
Cc: Matthijs van Duin 
Cc: Sekhar Nori 
Cc: Tero Kristo 
Signed-off-by: Tony Lindgren 
Cc: stable 
Signed-off-by: Greg Kroah-Hartman