<feed xmlns='http://www.w3.org/2005/Atom'>
<title>linux-stable.git/drivers/tty/serial, branch v6.2.8</title>
<subtitle>Linux kernel stable tree</subtitle>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/'/>
<entry>
<title>serial: 8250: ASPEED_VUART: select REGMAP instead of depending on it</title>
<updated>2023-03-22T12:37:58+00:00</updated>
<author>
<name>Randy Dunlap</name>
<email>rdunlap@infradead.org</email>
</author>
<published>2023-02-26T05:39:53+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=32f36bc91f9132879fb390c543985858a88888b2'/>
<id>32f36bc91f9132879fb390c543985858a88888b2</id>
<content type='text'>
commit f8086d1a65ac693e3fd863128352b4b11ee7324d upstream.

REGMAP is a hidden (not user visible) symbol. Users cannot set it
directly thru "make *config", so drivers should select it instead of
depending on it if they need it.

Consistently using "select" or "depends on" can also help reduce
Kconfig circular dependency issues.

Therefore, change the use of "depends on REGMAP" to "select REGMAP".

Fixes: 8d310c9107a2 ("drivers/tty/serial/8250: Make Aspeed VUART SIRQ polarity configurable")
Cc: stable &lt;stable@kernel.org&gt;
Signed-off-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Oskar Senft &lt;osk@google.com&gt;
Cc: linux-serial@vger.kernel.org
Link: https://lore.kernel.org/r/20230226053953.4681-9-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit f8086d1a65ac693e3fd863128352b4b11ee7324d upstream.

REGMAP is a hidden (not user visible) symbol. Users cannot set it
directly thru "make *config", so drivers should select it instead of
depending on it if they need it.

Consistently using "select" or "depends on" can also help reduce
Kconfig circular dependency issues.

Therefore, change the use of "depends on REGMAP" to "select REGMAP".

Fixes: 8d310c9107a2 ("drivers/tty/serial/8250: Make Aspeed VUART SIRQ polarity configurable")
Cc: stable &lt;stable@kernel.org&gt;
Signed-off-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Cc: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Cc: Oskar Senft &lt;osk@google.com&gt;
Cc: linux-serial@vger.kernel.org
Link: https://lore.kernel.org/r/20230226053953.4681-9-rdunlap@infradead.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>serial: 8250_fsl: fix handle_irq locking</title>
<updated>2023-03-22T12:37:57+00:00</updated>
<author>
<name>Johan Hovold</name>
<email>johan@kernel.org</email>
</author>
<published>2023-02-27T08:50:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=f0ff9d2e2d9f61467ec4838705dded40204429a2'/>
<id>f0ff9d2e2d9f61467ec4838705dded40204429a2</id>
<content type='text'>
commit 6e01f9a594ee0f69fb52cc8d11971612b4817f0b upstream.

The 8250 handle_irq callback is not just called from the interrupt
handler but also from a timer callback when polling (e.g. for ports
without an interrupt line). Consequently the callback must explicitly
disable interrupts to avoid a potential deadlock with another interrupt
in polled mode.

Fix up the two paths in the freescale callback that failed to re-enable
interrupts when polling.

Fixes: 853a9ae29e97 ("serial: 8250: fix handle_irq locking")
Cc: stable@vger.kernel.org	# 5.13
Reported-by: Dan Carpenter &lt;error27@gmail.com&gt;
Link: https://lore.kernel.org/r/Y/xYzqp4ogmOF5t0@kili
Signed-off-by: Johan Hovold &lt;johan@kernel.org&gt;
Acked-by: Jiri Slaby &lt;jirislaby@kernel.org&gt;
Link: https://lore.kernel.org/r/20230227085046.24282-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 6e01f9a594ee0f69fb52cc8d11971612b4817f0b upstream.

The 8250 handle_irq callback is not just called from the interrupt
handler but also from a timer callback when polling (e.g. for ports
without an interrupt line). Consequently the callback must explicitly
disable interrupts to avoid a potential deadlock with another interrupt
in polled mode.

Fix up the two paths in the freescale callback that failed to re-enable
interrupts when polling.

Fixes: 853a9ae29e97 ("serial: 8250: fix handle_irq locking")
Cc: stable@vger.kernel.org	# 5.13
Reported-by: Dan Carpenter &lt;error27@gmail.com&gt;
Link: https://lore.kernel.org/r/Y/xYzqp4ogmOF5t0@kili
Signed-off-by: Johan Hovold &lt;johan@kernel.org&gt;
Acked-by: Jiri Slaby &lt;jirislaby@kernel.org&gt;
Link: https://lore.kernel.org/r/20230227085046.24282-1-johan@kernel.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>serial: 8250_em: Fix UART port type</title>
<updated>2023-03-22T12:37:57+00:00</updated>
<author>
<name>Biju Das</name>
<email>biju.das.jz@bp.renesas.com</email>
</author>
<published>2023-02-27T11:41:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=d3310e840ed05d587f548126e3421ceb40debcca'/>
<id>d3310e840ed05d587f548126e3421ceb40debcca</id>
<content type='text'>
commit 32e293be736b853f168cd065d9cbc1b0c69f545d upstream.

As per HW manual for  EMEV2 "R19UH0040EJ0400 Rev.4.00", the UART
IP found on EMMA mobile SoC is Register-compatible with the
general-purpose 16750 UART chip. Fix UART port type as 16750 and
enable 64-bytes fifo support.

Fixes: 22886ee96895 ("serial8250-em: Emma Mobile UART driver V2")
Cc: stable@vger.kernel.org
Signed-off-by: Biju Das &lt;biju.das.jz@bp.renesas.com&gt;
Link: https://lore.kernel.org/r/20230227114152.22265-2-biju.das.jz@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 32e293be736b853f168cd065d9cbc1b0c69f545d upstream.

As per HW manual for  EMEV2 "R19UH0040EJ0400 Rev.4.00", the UART
IP found on EMMA mobile SoC is Register-compatible with the
general-purpose 16750 UART chip. Fix UART port type as 16750 and
enable 64-bytes fifo support.

Fixes: 22886ee96895 ("serial8250-em: Emma Mobile UART driver V2")
Cc: stable@vger.kernel.org
Signed-off-by: Biju Das &lt;biju.das.jz@bp.renesas.com&gt;
Link: https://lore.kernel.org/r/20230227114152.22265-2-biju.das.jz@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: serial: fsl_lpuart: skip waiting for transmission complete when UARTCTRL_SBK is asserted</title>
<updated>2023-03-22T12:37:57+00:00</updated>
<author>
<name>Sherry Sun</name>
<email>sherry.sun@nxp.com</email>
</author>
<published>2023-02-23T09:39:41+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=c5e655f4230f8a21f0412695a0ad6ada7fadac0a'/>
<id>c5e655f4230f8a21f0412695a0ad6ada7fadac0a</id>
<content type='text'>
commit 2411fd94ceaa6e11326e95d6ebf876cbfed28d23 upstream.

According to LPUART RM, Transmission Complete Flag becomes 0 if queuing
a break character by writing 1 to CTRL[SBK], so here need to skip
waiting for transmission complete when UARTCTRL_SBK is asserted,
otherwise the kernel may stuck here.
And actually set_termios() adds transmission completion waiting to avoid
data loss or data breakage when changing the baud rate, but we don't
need to worry about this when queuing break characters.

Signed-off-by: Sherry Sun &lt;sherry.sun@nxp.com&gt;
Cc: stable &lt;stable@kernel.org&gt;
Link: https://lore.kernel.org/r/20230223093941.31790-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 2411fd94ceaa6e11326e95d6ebf876cbfed28d23 upstream.

According to LPUART RM, Transmission Complete Flag becomes 0 if queuing
a break character by writing 1 to CTRL[SBK], so here need to skip
waiting for transmission complete when UARTCTRL_SBK is asserted,
otherwise the kernel may stuck here.
And actually set_termios() adds transmission completion waiting to avoid
data loss or data breakage when changing the baud rate, but we don't
need to worry about this when queuing break characters.

Signed-off-by: Sherry Sun &lt;sherry.sun@nxp.com&gt;
Cc: stable &lt;stable@kernel.org&gt;
Link: https://lore.kernel.org/r/20230223093941.31790-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: serial: fsl_lpuart: fix race on RX DMA shutdown</title>
<updated>2023-03-22T12:37:57+00:00</updated>
<author>
<name>Alexander Sverdlin</name>
<email>alexander.sverdlin@siemens.com</email>
</author>
<published>2023-03-09T13:43:02+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=2a36b444cace9580380467fd1183bb5e85bcc80a'/>
<id>2a36b444cace9580380467fd1183bb5e85bcc80a</id>
<content type='text'>
commit 1be6f2b15f902c02e055ae0b419ca789200473c9 upstream.

From time to time DMA completion can come in the middle of DMA shutdown:

&lt;process ctx&gt;:				&lt;IRQ&gt;:
lpuart32_shutdown()
  lpuart_dma_shutdown()
    del_timer_sync()
					lpuart_dma_rx_complete()
					  lpuart_copy_rx_to_tty()
					    mod_timer()
    lpuart_dma_rx_free()

When the timer fires a bit later, sport-&gt;dma_rx_desc is NULL:

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004
pc : lpuart_copy_rx_to_tty+0xcc/0x5bc
lr : lpuart_timer_func+0x1c/0x2c
Call trace:
 lpuart_copy_rx_to_tty
 lpuart_timer_func
 call_timer_fn
 __run_timers.part.0
 run_timer_softirq
 __do_softirq
 __irq_exit_rcu
 irq_exit
 handle_domain_irq
 gic_handle_irq
 call_on_irq_stack
 do_interrupt_handler
 ...

To fix this fold del_timer_sync() into lpuart_dma_rx_free() after
dmaengine_terminate_sync() to make sure timer will not be re-started in
lpuart_copy_rx_to_tty() &lt;= lpuart_dma_rx_complete().

Fixes: 4a8588a1cf86 ("serial: fsl_lpuart: delete timer on shutdown")
Cc: stable &lt;stable@kernel.org&gt;
Signed-off-by: Alexander Sverdlin &lt;alexander.sverdlin@siemens.com&gt;
Link: https://lore.kernel.org/r/20230309134302.74940-2-alexander.sverdlin@siemens.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 1be6f2b15f902c02e055ae0b419ca789200473c9 upstream.

From time to time DMA completion can come in the middle of DMA shutdown:

&lt;process ctx&gt;:				&lt;IRQ&gt;:
lpuart32_shutdown()
  lpuart_dma_shutdown()
    del_timer_sync()
					lpuart_dma_rx_complete()
					  lpuart_copy_rx_to_tty()
					    mod_timer()
    lpuart_dma_rx_free()

When the timer fires a bit later, sport-&gt;dma_rx_desc is NULL:

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000004
pc : lpuart_copy_rx_to_tty+0xcc/0x5bc
lr : lpuart_timer_func+0x1c/0x2c
Call trace:
 lpuart_copy_rx_to_tty
 lpuart_timer_func
 call_timer_fn
 __run_timers.part.0
 run_timer_softirq
 __do_softirq
 __irq_exit_rcu
 irq_exit
 handle_domain_irq
 gic_handle_irq
 call_on_irq_stack
 do_interrupt_handler
 ...

To fix this fold del_timer_sync() into lpuart_dma_rx_free() after
dmaengine_terminate_sync() to make sure timer will not be re-started in
lpuart_copy_rx_to_tty() &lt;= lpuart_dma_rx_complete().

Fixes: 4a8588a1cf86 ("serial: fsl_lpuart: delete timer on shutdown")
Cc: stable &lt;stable@kernel.org&gt;
Signed-off-by: Alexander Sverdlin &lt;alexander.sverdlin@siemens.com&gt;
Link: https://lore.kernel.org/r/20230309134302.74940-2-alexander.sverdlin@siemens.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>Revert "tty: serial: fsl_lpuart: adjust SERIAL_FSL_LPUART_CONSOLE config dependency"</title>
<updated>2023-03-22T12:37:57+00:00</updated>
<author>
<name>Tom Rix</name>
<email>trix@redhat.com</email>
</author>
<published>2023-02-26T17:38:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=0c712dc9e2a66076c8053079d1d11e5f8bd52744'/>
<id>0c712dc9e2a66076c8053079d1d11e5f8bd52744</id>
<content type='text'>
commit 2d638be71155b2e036aca1966b6129e2d661e91f upstream.

This reverts commit 5779a072c248db7a40cfd0f5ea958097fd1d9a30.

This results in a link error of

ld: drivers/tty/serial/earlycon.o: in function `parse_options':
drivers/tty/serial/earlycon.c:99: undefined reference to `uart_parse_earlycon'

When the config is in this state

CONFIG_SERIAL_CORE=m
CONFIG_SERIAL_CORE_CONSOLE=y
CONFIG_SERIAL_EARLYCON=y
CONFIG_SERIAL_FSL_LPUART=m
CONFIG_SERIAL_FSL_LPUART_CONSOLE=y

Fixes: 5779a072c248 ("tty: serial: fsl_lpuart: adjust SERIAL_FSL_LPUART_CONSOLE config dependency")
Cc: stable &lt;stable@kernel.org&gt;
Signed-off-by: Tom Rix &lt;trix@redhat.com&gt;
Reviewed-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Acked-by: Jiri Slaby &lt;jirislaby@kernel.org&gt;
Link: https://lore.kernel.org/r/20230226173846.236691-1-trix@redhat.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
commit 2d638be71155b2e036aca1966b6129e2d661e91f upstream.

This reverts commit 5779a072c248db7a40cfd0f5ea958097fd1d9a30.

This results in a link error of

ld: drivers/tty/serial/earlycon.o: in function `parse_options':
drivers/tty/serial/earlycon.c:99: undefined reference to `uart_parse_earlycon'

When the config is in this state

CONFIG_SERIAL_CORE=m
CONFIG_SERIAL_CORE_CONSOLE=y
CONFIG_SERIAL_EARLYCON=y
CONFIG_SERIAL_FSL_LPUART=m
CONFIG_SERIAL_FSL_LPUART_CONSOLE=y

Fixes: 5779a072c248 ("tty: serial: fsl_lpuart: adjust SERIAL_FSL_LPUART_CONSOLE config dependency")
Cc: stable &lt;stable@kernel.org&gt;
Signed-off-by: Tom Rix &lt;trix@redhat.com&gt;
Reviewed-by: Randy Dunlap &lt;rdunlap@infradead.org&gt;
Acked-by: Jiri Slaby &lt;jirislaby@kernel.org&gt;
Link: https://lore.kernel.org/r/20230226173846.236691-1-trix@redhat.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: pcn_uart: fix memory leak with using debugfs_lookup()</title>
<updated>2023-03-11T12:50:45+00:00</updated>
<author>
<name>Greg Kroah-Hartman</name>
<email>gregkh@linuxfoundation.org</email>
</author>
<published>2023-02-02T14:12:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=139769c4bd8273b5e3f85ea474aa37018fe7e436'/>
<id>139769c4bd8273b5e3f85ea474aa37018fe7e436</id>
<content type='text'>
[ Upstream commit 04a189c720aa2b6091442113ce9b9bc93552dff8 ]

When calling debugfs_lookup() the result must have dput() called on it,
otherwise the memory will leak over time.  To make things simpler, just
call debugfs_lookup_and_remove() instead which handles all of the logic
at once.

Cc: Jiri Slaby &lt;jirislaby@kernel.org&gt;
Link: https://lore.kernel.org/r/20230202141221.2293012-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit 04a189c720aa2b6091442113ce9b9bc93552dff8 ]

When calling debugfs_lookup() the result must have dput() called on it,
otherwise the memory will leak over time.  To make things simpler, just
call debugfs_lookup_and_remove() instead which handles all of the logic
at once.

Cc: Jiri Slaby &lt;jirislaby@kernel.org&gt;
Link: https://lore.kernel.org/r/20230202141221.2293012-1-gregkh@linuxfoundation.org
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>serial: sc16is7xx: setup GPIO controller later in probe</title>
<updated>2023-03-11T12:50:40+00:00</updated>
<author>
<name>Isaac True</name>
<email>isaac.true@canonical.com</email>
</author>
<published>2022-11-30T10:55:30+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=b71ff206707855ce73c04794c76f7b678b2d4f72'/>
<id>b71ff206707855ce73c04794c76f7b678b2d4f72</id>
<content type='text'>
[ Upstream commit c8f71b49ee4d28930c4a6798d1969fa91dc4ef3e ]

The GPIO controller component of the sc16is7xx driver is setup too
early, which can result in a race condition where another device tries
to utilise the GPIO lines before the sc16is7xx device has finished
initialising.

This issue manifests itself as an Oops when the GPIO lines are configured:

    Unable to handle kernel read from unreadable memory at virtual address
    ...
    pc : sc16is7xx_gpio_direction_output+0x68/0x108 [sc16is7xx]
    lr : sc16is7xx_gpio_direction_output+0x4c/0x108 [sc16is7xx]
    ...
    Call trace:
    sc16is7xx_gpio_direction_output+0x68/0x108 [sc16is7xx]
    gpiod_direction_output_raw_commit+0x64/0x318
    gpiod_direction_output+0xb0/0x170
    create_gpio_led+0xec/0x198
    gpio_led_probe+0x16c/0x4f0
    platform_drv_probe+0x5c/0xb0
    really_probe+0xe8/0x448
    driver_probe_device+0xe8/0x138
    __device_attach_driver+0x94/0x118
    bus_for_each_drv+0x8c/0xe0
    __device_attach+0x100/0x1b8
    device_initial_probe+0x28/0x38
    bus_probe_device+0xa4/0xb0
    deferred_probe_work_func+0x90/0xe0
    process_one_work+0x1c4/0x480
    worker_thread+0x54/0x430
    kthread+0x138/0x150
    ret_from_fork+0x10/0x1c

This patch moves the setup of the GPIO controller functions to later in the
probe function, ensuring the sc16is7xx device has already finished
initialising by the time other devices try to make use of the GPIO lines.
The error handling has also been reordered to reflect the new
initialisation order.

Co-developed-by: Wen-chien Jesse Sung &lt;jesse.sung@canonical.com&gt;
Signed-off-by: Wen-chien Jesse Sung &lt;jesse.sung@canonical.com&gt;
Signed-off-by: Isaac True &lt;isaac.true@canonical.com&gt;
Link: https://lore.kernel.org/r/20221130105529.698385-1-isaac.true@canonical.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit c8f71b49ee4d28930c4a6798d1969fa91dc4ef3e ]

The GPIO controller component of the sc16is7xx driver is setup too
early, which can result in a race condition where another device tries
to utilise the GPIO lines before the sc16is7xx device has finished
initialising.

This issue manifests itself as an Oops when the GPIO lines are configured:

    Unable to handle kernel read from unreadable memory at virtual address
    ...
    pc : sc16is7xx_gpio_direction_output+0x68/0x108 [sc16is7xx]
    lr : sc16is7xx_gpio_direction_output+0x4c/0x108 [sc16is7xx]
    ...
    Call trace:
    sc16is7xx_gpio_direction_output+0x68/0x108 [sc16is7xx]
    gpiod_direction_output_raw_commit+0x64/0x318
    gpiod_direction_output+0xb0/0x170
    create_gpio_led+0xec/0x198
    gpio_led_probe+0x16c/0x4f0
    platform_drv_probe+0x5c/0xb0
    really_probe+0xe8/0x448
    driver_probe_device+0xe8/0x138
    __device_attach_driver+0x94/0x118
    bus_for_each_drv+0x8c/0xe0
    __device_attach+0x100/0x1b8
    device_initial_probe+0x28/0x38
    bus_probe_device+0xa4/0xb0
    deferred_probe_work_func+0x90/0xe0
    process_one_work+0x1c4/0x480
    worker_thread+0x54/0x430
    kthread+0x138/0x150
    ret_from_fork+0x10/0x1c

This patch moves the setup of the GPIO controller functions to later in the
probe function, ensuring the sc16is7xx device has already finished
initialising by the time other devices try to make use of the GPIO lines.
The error handling has also been reordered to reflect the new
initialisation order.

Co-developed-by: Wen-chien Jesse Sung &lt;jesse.sung@canonical.com&gt;
Signed-off-by: Wen-chien Jesse Sung &lt;jesse.sung@canonical.com&gt;
Signed-off-by: Isaac True &lt;isaac.true@canonical.com&gt;
Link: https://lore.kernel.org/r/20221130105529.698385-1-isaac.true@canonical.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: serial: fsl_lpuart: disable the CTS when send break signal</title>
<updated>2023-03-11T12:50:40+00:00</updated>
<author>
<name>Sherry Sun</name>
<email>sherry.sun@nxp.com</email>
</author>
<published>2022-12-14T03:11:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=5c0f48eb59c12632d6ac4e9ebebe928bd1ad3f1d'/>
<id>5c0f48eb59c12632d6ac4e9ebebe928bd1ad3f1d</id>
<content type='text'>
[ Upstream commit c4c81db5cf8bc53d6160c3abf26d382c841aa434 ]

LPUART IP has a bug that it treats the CTS as higher priority than the
break signal, which cause the break signal sending through UARTCTRL_SBK
may impacted by the CTS input if the HW flow control is enabled.

Add this workaround patch to fix the IP bug, we can disable CTS before
asserting SBK to avoid any interference from CTS, and re-enable it when
break off.

Such as for the bluetooth chip power save feature, host can let the BT
chip get into sleep state by sending a UART break signal, and wake it up
by turning off the UART break. If the BT chip enters the sleep mode
successfully, it will pull up the CTS line, if the BT chip is woken up,
it will pull down the CTS line. If without this workaround patch, the
UART TX pin cannot send the break signal successfully as it affected by
the BT CTS pin. After adding this patch, the BT power save feature can
work well.

Signed-off-by: Sherry Sun &lt;sherry.sun@nxp.com&gt;
Link: https://lore.kernel.org/r/20221214031137.28815-2-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit c4c81db5cf8bc53d6160c3abf26d382c841aa434 ]

LPUART IP has a bug that it treats the CTS as higher priority than the
break signal, which cause the break signal sending through UARTCTRL_SBK
may impacted by the CTS input if the HW flow control is enabled.

Add this workaround patch to fix the IP bug, we can disable CTS before
asserting SBK to avoid any interference from CTS, and re-enable it when
break off.

Such as for the bluetooth chip power save feature, host can let the BT
chip get into sleep state by sending a UART break signal, and wake it up
by turning off the UART break. If the BT chip enters the sleep mode
successfully, it will pull up the CTS line, if the BT chip is woken up,
it will pull down the CTS line. If without this workaround patch, the
UART TX pin cannot send the break signal successfully as it affected by
the BT CTS pin. After adding this patch, the BT power save feature can
work well.

Signed-off-by: Sherry Sun &lt;sherry.sun@nxp.com&gt;
Link: https://lore.kernel.org/r/20221214031137.28815-2-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
<entry>
<title>tty: serial: imx: disable Ageing Timer interrupt request irq</title>
<updated>2023-03-10T08:28:55+00:00</updated>
<author>
<name>Peng Fan</name>
<email>peng.fan@nxp.com</email>
</author>
<published>2023-02-06T01:30:16+00:00</published>
<link rel='alternate' type='text/html' href='https://git.tavy.me/linux-stable.git/commit/?id=963875b0655197281775b0ea614aab8b6b3eb001'/>
<id>963875b0655197281775b0ea614aab8b6b3eb001</id>
<content type='text'>
[ Upstream commit ef25e16ea9674b713a68c3bda821556ce9901254 ]

There maybe pending USR interrupt before requesting irq, however
uart_add_one_port has not executed, so there will be kernel panic:
[    0.795668] Unable to handle kernel NULL pointer dereference at virtual addre
ss 0000000000000080
[    0.802701] Mem abort info:
[    0.805367]   ESR = 0x0000000096000004
[    0.808950]   EC = 0x25: DABT (current EL), IL = 32 bits
[    0.814033]   SET = 0, FnV = 0
[    0.816950]   EA = 0, S1PTW = 0
[    0.819950]   FSC = 0x04: level 0 translation fault
[    0.824617] Data abort info:
[    0.827367]   ISV = 0, ISS = 0x00000004
[    0.831033]   CM = 0, WnR = 0
[    0.833866] [0000000000000080] user address but active_mm is swapper
[    0.839951] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
[    0.845953] Modules linked in:
[    0.848869] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.1.1+g56321e101aca #1
[    0.855617] Hardware name: Freescale i.MX8MP EVK (DT)
[    0.860452] pstate: 000000c5 (nzcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[    0.867117] pc : __imx_uart_rxint.constprop.0+0x11c/0x2c0
[    0.872283] lr : imx_uart_int+0xf8/0x1ec

The issue only happends in the inmate linux when Jailhouse hypervisor
enabled. The test procedure is:
while true; do
	jailhouse enable imx8mp.cell
	jailhouse cell linux xxxx
	sleep 10
	jailhouse cell destroy 1
	jailhouse disable
	sleep 5
done

And during the upper test, press keys to the 2nd linux console.
When `jailhouse cell destroy 1`, the 2nd linux has no chance to put
the uart to a quiese state, so USR1/2 may has pending interrupts. Then
when `jailhosue cell linux xx` to start 2nd linux again, the issue
trigger.

In order to disable irqs before requesting them, both UCR1 and UCR2 irqs
should be disabled, so here fix that, disable the Ageing Timer interrupt
in UCR2 as UCR1 does.

Fixes: 8a61f0c70ae6 ("serial: imx: Disable irqs before requesting them")
Suggested-by: Sherry Sun &lt;sherry.sun@nxp.com&gt;
Reviewed-by: Sherry Sun &lt;sherry.sun@nxp.com&gt;
Signed-off-by: Peng Fan &lt;peng.fan@nxp.com&gt;
Acked-by: Jason Liu &lt;jason.hui.liu@nxp.com&gt;
Link: https://lore.kernel.org/r/20230206013016.29352-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</content>
<content type='xhtml'>
<div xmlns='http://www.w3.org/1999/xhtml'>
<pre>
[ Upstream commit ef25e16ea9674b713a68c3bda821556ce9901254 ]

There maybe pending USR interrupt before requesting irq, however
uart_add_one_port has not executed, so there will be kernel panic:
[    0.795668] Unable to handle kernel NULL pointer dereference at virtual addre
ss 0000000000000080
[    0.802701] Mem abort info:
[    0.805367]   ESR = 0x0000000096000004
[    0.808950]   EC = 0x25: DABT (current EL), IL = 32 bits
[    0.814033]   SET = 0, FnV = 0
[    0.816950]   EA = 0, S1PTW = 0
[    0.819950]   FSC = 0x04: level 0 translation fault
[    0.824617] Data abort info:
[    0.827367]   ISV = 0, ISS = 0x00000004
[    0.831033]   CM = 0, WnR = 0
[    0.833866] [0000000000000080] user address but active_mm is swapper
[    0.839951] Internal error: Oops: 0000000096000004 [#1] PREEMPT SMP
[    0.845953] Modules linked in:
[    0.848869] CPU: 0 PID: 1 Comm: swapper/0 Not tainted 6.1.1+g56321e101aca #1
[    0.855617] Hardware name: Freescale i.MX8MP EVK (DT)
[    0.860452] pstate: 000000c5 (nzcv daIF -PAN -UAO -TCO -DIT -SSBS BTYPE=--)
[    0.867117] pc : __imx_uart_rxint.constprop.0+0x11c/0x2c0
[    0.872283] lr : imx_uart_int+0xf8/0x1ec

The issue only happends in the inmate linux when Jailhouse hypervisor
enabled. The test procedure is:
while true; do
	jailhouse enable imx8mp.cell
	jailhouse cell linux xxxx
	sleep 10
	jailhouse cell destroy 1
	jailhouse disable
	sleep 5
done

And during the upper test, press keys to the 2nd linux console.
When `jailhouse cell destroy 1`, the 2nd linux has no chance to put
the uart to a quiese state, so USR1/2 may has pending interrupts. Then
when `jailhosue cell linux xx` to start 2nd linux again, the issue
trigger.

In order to disable irqs before requesting them, both UCR1 and UCR2 irqs
should be disabled, so here fix that, disable the Ageing Timer interrupt
in UCR2 as UCR1 does.

Fixes: 8a61f0c70ae6 ("serial: imx: Disable irqs before requesting them")
Suggested-by: Sherry Sun &lt;sherry.sun@nxp.com&gt;
Reviewed-by: Sherry Sun &lt;sherry.sun@nxp.com&gt;
Signed-off-by: Peng Fan &lt;peng.fan@nxp.com&gt;
Acked-by: Jason Liu &lt;jason.hui.liu@nxp.com&gt;
Link: https://lore.kernel.org/r/20230206013016.29352-1-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman &lt;gregkh@linuxfoundation.org&gt;
Signed-off-by: Sasha Levin &lt;sashal@kernel.org&gt;
</pre>
</div>
</content>
</entry>
</feed>
