linux-stable.git/drivers/tty, branch v6.18.4 Linux kernel stable tree serial: sh-sci: Check that the DMA cookie is valid 2026-01-02T11:57:15+00:00 Claudiu Beznea claudiu.beznea.uj@bp.renesas.com 2025-12-17T13:57:59+00:00 17157612e40d90c13e5b571c91b0cf2b5b825770 commit c3ca8a0aac832fe8047608bb2ae2cca314c6d717 upstream. The driver updates struct sci_port::tx_cookie to zero right before the TX work is scheduled, or to -EINVAL when DMA is disabled. dma_async_is_complete(), called through dma_cookie_status() (and possibly through dmaengine_tx_status()), considers cookies valid only if they have values greater than or equal to 1. Passing zero or -EINVAL to dmaengine_tx_status() before any TX DMA transfer has started leads to an incorrect TX status being reported, as the cookie is invalid for the DMA subsystem. This may cause long wait times when the serial device is opened for configuration before any TX activity has occurred. Check that the TX cookie is valid before passing it to dmaengine_tx_status(). Fixes: 7cc0e0a43a91 ("serial: sh-sci: Check if TX data was written to device in .tx_empty()") Cc: stable <stable@kernel.org> Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com> Link: https://patch.msgid.link/20251217135759.402015-1-claudiu.beznea.uj@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit c3ca8a0aac832fe8047608bb2ae2cca314c6d717 upstream.

The driver updates struct sci_port::tx_cookie to zero right before the TX
work is scheduled, or to -EINVAL when DMA is disabled.
dma_async_is_complete(), called through dma_cookie_status() (and possibly
through dmaengine_tx_status()), considers cookies valid only if they have
values greater than or equal to 1.

Passing zero or -EINVAL to dmaengine_tx_status() before any TX DMA
transfer has started leads to an incorrect TX status being reported, as the
cookie is invalid for the DMA subsystem. This may cause long wait times
when the serial device is opened for configuration before any TX activity
has occurred.

Check that the TX cookie is valid before passing it to
dmaengine_tx_status().

Fixes: 7cc0e0a43a91 ("serial: sh-sci: Check if TX data was written to device in .tx_empty()")
Cc: stable <stable@kernel.org>
Signed-off-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Link: https://patch.msgid.link/20251217135759.402015-1-claudiu.beznea.uj@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: xilinx_uartps: fix rs485 delay_rts_after_send 2026-01-02T11:57:15+00:00 j.turek jakub.turek@elsta.tech 2025-12-21T10:32:21+00:00 190dc4b74800746146db12ed669b26ac773003eb commit 267ee93c417e685d9f8e079e41c70ba6ee4df5a5 upstream. RTS line control with delay should be triggered when there is no more bytes in kfifo and hardware buffer is empty. Without this patch RTS control is scheduled right after feeding hardware buffer and this is too early. RTS line may change state before hardware buffer is empty. With this patch delayed RTS state change is triggered when function cdns_uart_handle_tx is called from cdns_uart_isr on CDNS_UART_IXR_TXEMPTY exactly when hardware completed transmission Fixes: fccc9d9233f9 ("tty: serial: uartps: Add rs485 support to uartps driver") Cc: stable <stable@kernel.org> Link: https://patch.msgid.link/20251221103221.1971125-1-jakub.turek@elsta.tech Signed-off-by: Jakub Turek <jakub.turek@elsta.tech> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 267ee93c417e685d9f8e079e41c70ba6ee4df5a5 upstream.

RTS line control with delay should be triggered when there is no more
bytes in kfifo and hardware buffer is empty. Without this patch RTS
control is scheduled right after feeding hardware buffer and this is too
early.

RTS line may change state before hardware buffer is empty.

With this patch delayed RTS state change is triggered when function
cdns_uart_handle_tx is called from cdns_uart_isr on
CDNS_UART_IXR_TXEMPTY exactly when hardware completed transmission

Fixes: fccc9d9233f9 ("tty: serial: uartps: Add rs485 support to uartps driver")
Cc: stable <stable@kernel.org>
Link: https://patch.msgid.link/20251221103221.1971125-1-jakub.turek@elsta.tech
Signed-off-by: Jakub Turek  <jakub.turek@elsta.tech>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: core: Fix serial device initialization 2026-01-02T11:57:15+00:00 Alexander Stein alexander.stein@ew.tq-group.com 2025-12-19T15:28:12+00:00 320578703ebeca2d96f818d547bacc8ea9afac3c commit f54151148b969fb4b62bec8093d255306d20df30 upstream. During restoring sysfs fwnode information the information of_node_reused was dropped. This was previously set by device_set_of_node_from_dev(). Add it back manually Fixes: 24ec03cc5512 ("serial: core: Restore sysfs fwnode information") Cc: stable <stable@kernel.org> Suggested-by: Cosmin Tanislav <demonsingur@gmail.com> Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com> Tested-by: Michael Walle <mwalle@kernel.org> Tested-by: Marek Szyprowski <m.szyprowski@samsung.com> Tested-by: Cosmin Tanislav <demonsingur@gmail.com> Link: https://patch.msgid.link/20251219152813.1893982-1-alexander.stein@ew.tq-group.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit f54151148b969fb4b62bec8093d255306d20df30 upstream.

During restoring sysfs fwnode information the information of_node_reused
was dropped. This was previously set by device_set_of_node_from_dev().
Add it back manually

Fixes: 24ec03cc5512 ("serial: core: Restore sysfs fwnode information")
Cc: stable <stable@kernel.org>
Suggested-by: Cosmin Tanislav <demonsingur@gmail.com>
Signed-off-by: Alexander Stein <alexander.stein@ew.tq-group.com>
Tested-by: Michael Walle <mwalle@kernel.org>
Tested-by: Marek Szyprowski <m.szyprowski@samsung.com>
Tested-by: Cosmin Tanislav <demonsingur@gmail.com>
Link: https://patch.msgid.link/20251219152813.1893982-1-alexander.stein@ew.tq-group.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: core: Restore sysfs fwnode information 2026-01-02T11:57:15+00:00 Andy Shevchenko andriy.shevchenko@linux.intel.com 2025-11-27T16:36:50+00:00 c255a5164c58ae6c0f993e431843a965088e6ed8 commit 24ec03cc55126b7b3adf102f4b3d9f716532b329 upstream. The change that restores sysfs fwnode information does it only for OF cases. Update the fix to cover all possible types of fwnodes. Fixes: d36f0e9a0002 ("serial: core: restore of_node information in sysfs") Cc: stable <stable@kernel.org> Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Link: https://patch.msgid.link/20251127163650.2942075-1-andriy.shevchenko@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 24ec03cc55126b7b3adf102f4b3d9f716532b329 upstream.

The change that restores sysfs fwnode information does it only for OF cases.
Update the fix to cover all possible types of fwnodes.

Fixes: d36f0e9a0002 ("serial: core: restore of_node information in sysfs")
Cc: stable <stable@kernel.org>
Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Link: https://patch.msgid.link/20251127163650.2942075-1-andriy.shevchenko@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: sprd: Return -EPROBE_DEFER when uart clock is not ready 2026-01-02T11:57:02+00:00 Wenhua Lin Wenhua.Lin@unisoc.com 2025-10-22T03:08:40+00:00 ad9f0f01373c985b61e0e6be5e85685ab2a11635 [ Upstream commit 29e8a0c587e328ed458380a45d6028adf64d7487 ] In sprd_clk_init(), when devm_clk_get() returns -EPROBE_DEFER for either uart or source clock, we should propagate the error instead of just warning and continuing with NULL clocks. Currently the driver only emits a warning when clock acquisition fails and proceeds with NULL clock pointers. This can lead to issues later when the clocks are actually needed. More importantly, when the clock provider is not ready yet and returns -EPROBE_DEFER, we should return this error to allow deferred probing. This change adds explicit checks for -EPROBE_DEFER after both: 1. devm_clk_get(uport->dev, uart) 2. devm_clk_get(uport->dev, source) When -EPROBE_DEFER is encountered, the function now returns -EPROBE_DEFER to let the driver framework retry probing later when the clock dependencies are resolved. Signed-off-by: Wenhua Lin <Wenhua.Lin@unisoc.com> Link: https://patch.msgid.link/20251022030840.956589-1-Wenhua.Lin@unisoc.com Reviewed-by: Cixi Geng <cixi.geng@linux.dev> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit 29e8a0c587e328ed458380a45d6028adf64d7487 ]

In sprd_clk_init(), when devm_clk_get() returns -EPROBE_DEFER
for either uart or source clock, we should propagate the
error instead of just warning and continuing with NULL clocks.

Currently the driver only emits a warning when clock acquisition
fails and proceeds with NULL clock pointers. This can lead to
issues later when the clocks are actually needed. More importantly,
when the clock provider is not ready yet and returns -EPROBE_DEFER,
we should return this error to allow deferred probing.

This change adds explicit checks for -EPROBE_DEFER after both:
1. devm_clk_get(uport->dev, uart)
2. devm_clk_get(uport->dev, source)

When -EPROBE_DEFER is encountered, the function now returns
-EPROBE_DEFER to let the driver framework retry probing
later when the clock dependencies are resolved.

Signed-off-by: Wenhua Lin <Wenhua.Lin@unisoc.com>
Link: https://patch.msgid.link/20251022030840.956589-1-Wenhua.Lin@unisoc.com
Reviewed-by: Cixi Geng <cixi.geng@linux.dev>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
tty: serial: imx: Only configure the wake register when device is set as wakeup source 2025-12-18T13:02:34+00:00 Sherry Sun sherry.sun@nxp.com 2025-10-02T04:52:58+00:00 9ff72116e6c86545b60da5c1eb5344858c3daadd [ Upstream commit d55f3d2375ceeb08330d30f1e08196993c0b6583 ] Currently, the i.MX UART driver enables wake-related registers for all UART devices by default. However, this is unnecessary for devices that are not configured as wakeup sources. To address this, add a device_may_wakeup() check before configuring the UART wake-related registers. Fixes: db1a9b55004c ("tty: serial: imx: Allow UART to be a source for wakeup") Signed-off-by: Sherry Sun <sherry.sun@nxp.com> Reviewed-by: Frank Li <Frank.Li@nxp.com> Link: https://patch.msgid.link/20251002045259.2725461-2-sherry.sun@nxp.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org> 
[ Upstream commit d55f3d2375ceeb08330d30f1e08196993c0b6583 ]

Currently, the i.MX UART driver enables wake-related registers for all
UART devices by default. However, this is unnecessary for devices that
are not configured as wakeup sources. To address this, add a
device_may_wakeup() check before configuring the UART wake-related
registers.

Fixes: db1a9b55004c ("tty: serial: imx: Allow UART to be a source for wakeup")
Signed-off-by: Sherry Sun <sherry.sun@nxp.com>
Reviewed-by: Frank Li <Frank.Li@nxp.com>
Link: https://patch.msgid.link/20251002045259.2725461-2-sherry.sun@nxp.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
serial: sh-sci: Fix deadlock during RSCI FIFO overrun error 2025-12-12T17:42:46+00:00 Biju Das biju.das.jz@bp.renesas.com 2025-11-14T10:13:47+00:00 a1210a4023aaef57cbaf66066c78b3eefbc68731 commit 75a9f4c54770f062f4b3813a83667452b326dda3 upstream. On RSCI IP, a deadlock occurs during a FIFO overrun error, as it uses a different register to clear the FIFO overrun error status. Cc: stable@kernel.org Fixes: 0666e3fe95ab ("serial: sh-sci: Add support for RZ/T2H SCI") Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://patch.msgid.link/20251114101350.106699-3-biju.das.jz@bp.renesas.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 75a9f4c54770f062f4b3813a83667452b326dda3 upstream.

On RSCI IP, a deadlock occurs during a FIFO overrun error, as it uses a
different register to clear the FIFO overrun error status.

Cc: stable@kernel.org
Fixes: 0666e3fe95ab ("serial: sh-sci: Add support for RZ/T2H SCI")
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Link: https://patch.msgid.link/20251114101350.106699-3-biju.das.jz@bp.renesas.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: add support of CPCI cards 2025-12-12T17:42:46+00:00 Magne Bruno magne.bruno@addi-data.com 2025-11-10T16:24:56+00:00 48e5794baf58c5ad789fd3301991eaa60417a6f0 commit 0e5a99e0e5f50353b86939ff6e424800d769c818 upstream. Addi-Data GmbH is manufacturing multi-serial ports cards supporting CompactPCI (known as CPCI). Those cards are identified with different DeviceIds. Those cards integrating standard UARTs work the same way as PCI/PCIe models already supported in the serial driver. Signed-off-by: Magne Bruno <magne.bruno@addi-data.com> Link: https://patch.msgid.link/20251110162456.341029-1-magne.bruno@addi-data.com Cc: stable <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
commit 0e5a99e0e5f50353b86939ff6e424800d769c818 upstream.

Addi-Data GmbH is manufacturing multi-serial ports cards supporting CompactPCI (known as CPCI).
Those cards are identified with different DeviceIds. Those cards integrating standard UARTs
work the same way as PCI/PCIe models already supported in the serial driver.

Signed-off-by: Magne Bruno <magne.bruno@addi-data.com>
Link: https://patch.msgid.link/20251110162456.341029-1-magne.bruno@addi-data.com
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: 8250: Fix 8250_rsa symbol loop 2025-11-26T12:16:53+00:00 Ilpo Järvinen ilpo.jarvinen@linux.intel.com 2025-11-10T10:50:43+00:00 2bf95a9bcb50002ca9d47403d60aedaeb2e19abe Depmod fails for a kernel made with: make allnoconfig echo -e "CONFIG_MODULES=y\nCONFIG_SERIAL_8250=m\nCONFIG_SERIAL_8250_EXTENDED=y\nCONFIG_SERIAL_8250_RSA=y" >> .config make olddefconfig ...due to a dependency loop: depmod: ERROR: Cycle detected: 8250 -> 8250_base -> 8250 depmod: ERROR: Found 2 modules in dependency cycles! This is caused by the move of 8250 RSA code from 8250_port.c (in 8250_base.ko) into 8250_rsa.c (in 8250.ko) by the commit 5a128fb475fb ("serial: 8250: move RSA functions to 8250_rsa.c"). The commit b20d6576cdb3 ("serial: 8250: export RSA functions") tried to fix a missing symbol issue with EXPORTs but those then cause this dependency cycle. Break dependency loop by moving 8250_rsa.o from 8250.ko to 8250_base.ko and by passing univ8250_port_base_ops to univ8250_rsa_support() that can make a local copy of it. Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Reported-by: Alex Davis <alex47794@gmail.com> Fixes: 5a128fb475fb ("serial: 8250: move RSA functions to 8250_rsa.c") Fixes: b20d6576cdb3 ("serial: 8250: export RSA functions") Cc: stable <stable@kernel.org> Link: https://lore.kernel.org/all/87frc3sd8d.fsf@posteo.net/ Link: https://lore.kernel.org/all/CADiockCvM6v+d+UoFZpJSMoLAdpy99_h-hJdzUsdfaWGn3W7-g@mail.gmail.com/ Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Jiri Slaby <jirislaby@kernel.org> Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com> Link: https://patch.msgid.link/20251110105043.4062-1-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Depmod fails for a kernel made with:
  make allnoconfig
  echo -e "CONFIG_MODULES=y\nCONFIG_SERIAL_8250=m\nCONFIG_SERIAL_8250_EXTENDED=y\nCONFIG_SERIAL_8250_RSA=y" >> .config
  make olddefconfig

...due to a dependency loop:

  depmod: ERROR: Cycle detected: 8250 -> 8250_base -> 8250
  depmod: ERROR: Found 2 modules in dependency cycles!

This is caused by the move of 8250 RSA code from 8250_port.c (in
8250_base.ko) into 8250_rsa.c (in 8250.ko) by the commit 5a128fb475fb
("serial: 8250: move RSA functions to 8250_rsa.c"). The commit
b20d6576cdb3 ("serial: 8250: export RSA functions") tried to fix a
missing symbol issue with EXPORTs but those then cause this dependency
cycle.

Break dependency loop by moving 8250_rsa.o from 8250.ko to 8250_base.ko
and by passing univ8250_port_base_ops to univ8250_rsa_support() that
can make a local copy of it.

Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Reported-by: Alex Davis <alex47794@gmail.com>
Fixes: 5a128fb475fb ("serial: 8250: move RSA functions to 8250_rsa.c")
Fixes: b20d6576cdb3 ("serial: 8250: export RSA functions")
Cc: stable <stable@kernel.org>
Link: https://lore.kernel.org/all/87frc3sd8d.fsf@posteo.net/
Link: https://lore.kernel.org/all/CADiockCvM6v+d+UoFZpJSMoLAdpy99_h-hJdzUsdfaWGn3W7-g@mail.gmail.com/
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Reviewed-by: Jiri Slaby <jirislaby@kernel.org>
Signed-off-by: Ilpo Järvinen <ilpo.jarvinen@linux.intel.com>
Link: https://patch.msgid.link/20251110105043.4062-1-ilpo.jarvinen@linux.intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
serial: amba-pl011: prefer dma_mapping_error() over explicit address checking 2025-10-28T14:26:47+00:00 Miaoqian Lin linmq006@gmail.com 2025-10-27T09:20:50+00:00 eb4917f557d43c7a1c805dd73ffcdfddb2aba39a Check for returned DMA addresses using specialized dma_mapping_error() helper which is generally recommended for this purpose by Documentation/core-api/dma-api.rst: "In some circumstances dma_map_single(), ... will fail to create a mapping. A driver can check for these errors by testing the returned DMA address with dma_mapping_error()." Found via static analysis and this is similar to commit fa0308134d26 ("ALSA: memalloc: prefer dma_mapping_error() over explicit address checking") Fixes: 58ac1b379979 ("ARM: PL011: Fix DMA support") Cc: stable <stable@kernel.org> Signed-off-by: Miaoqian Lin <linmq006@gmail.com> Reviewed-by: Gregory CLEMENT <gregory.clement@bootlin.com> Link: https://patch.msgid.link/20251027092053.87937-1-linmq006@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> 
Check for returned DMA addresses using specialized dma_mapping_error()
helper which is generally recommended for this purpose by
Documentation/core-api/dma-api.rst:

  "In some circumstances dma_map_single(), ...
will fail to create a mapping. A driver can check for these errors
by testing the returned DMA address with dma_mapping_error()."

Found via static analysis and this is similar to commit fa0308134d26
("ALSA: memalloc: prefer dma_mapping_error() over explicit address checking")

Fixes: 58ac1b379979 ("ARM: PL011: Fix DMA support")
Cc: stable <stable@kernel.org>
Signed-off-by: Miaoqian Lin <linmq006@gmail.com>
Reviewed-by: Gregory CLEMENT <gregory.clement@bootlin.com>
Link: https://patch.msgid.link/20251027092053.87937-1-linmq006@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>