linux/drivers/tty, branch v6.16

pch_uart: Fix dma_sync_sg_for_device() nents value

2025-07-09T11:43:02Z

The dma_sync_sg_for_device() functions should be called with the same nents as the dma_map_sg(), not the value the map function returned according to the documentation in Documentation/core-api/dma-api.rst:450: With the sync_sg API, all the parameters must be the same as those passed into the sg mapping API. Fixes: da3564ee027e ("pch_uart: add multi-scatter processing") Cc: stable Signed-off-by: Thomas Fourier Reviewed-by: Andy Shevchenko Link: https://lore.kernel.org/r/20250701113452.18590-2-fourier.thomas@gmail.com Signed-off-by: Greg Kroah-Hartman

serial: core: fix OF node leak

2025-07-09T11:41:48Z

Make sure to drop the OF node reference taken when initialising the control and port devices when the devices are later released. Fixes: d36f0e9a0002 ("serial: core: restore of_node information in sysfs") Cc: Aidan Stewart Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20250708085817.16070-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

serial: imx: Restore original RXTL for console to fix data loss

2025-06-24T14:34:21Z

Commit 7a637784d517 ("serial: imx: reduce RX interrupt frequency") introduced a regression on the i.MX6UL EVK board. The issue can be reproduced with the following steps: - Open vi on the board. - Paste a text file (~150 characters). - Save the file, then repeat the process. - Compare the sha256sum of the saved files. The checksums do not match due to missing characters or entire lines. Fix this by restoring the RXTL value to 1 when the UART is used as a console. This ensures timely RX interrupts and reliable data reception in console mode. With this change, pasted content is saved correctly, and checksums are always consistent. Cc: stable Fixes: 7a637784d517 ("serial: imx: reduce RX interrupt frequency") Signed-off-by: Fabio Estevam Reviewed-by: Stefan Wahren Link: https://lore.kernel.org/r/20250619114617.2791939-1-festevam@gmail.com Signed-off-by: Greg Kroah-Hartman

serial: core: restore of_node information in sysfs

2025-06-19T11:27:48Z

Since in v6.8-rc1, the of_node symlink under tty devices is missing. This breaks any udev rules relying on this information. Link the of_node information in the serial controller device with the parent defined in the device tree. This will also apply to the serial device which takes the serial controller as a parent device. Fixes: b286f4e87e32 ("serial: core: Move tty and serdev to be children of serial core port device") Cc: stable@vger.kernel.org Signed-off-by: Aidan Stewart Link: https://lore.kernel.org/r/20250617164819.13912-1-astewart@tektelic.com Signed-off-by: Greg Kroah-Hartman

vt: fix kernel-doc warnings in ucs_get_fallback()

2025-06-19T11:27:36Z

Use the correct function parameter name in ucs_get_fallback() to prevent kernel-doc warnings: Warning: drivers/tty/vt/ucs.c:218 function parameter 'cp' not described in 'ucs_get_fallback' Warning: drivers/tty/vt/ucs.c:218 Excess function parameter 'base' description in 'ucs_get_fallback' Fixes: fe26933cf1e1 ("vt: add ucs_get_fallback()") Signed-off-by: Randy Dunlap Cc: Nicolas Pitre Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: linux-serial@vger.kernel.org Reviewed-by: Nicolas Pitre . Link: https://lore.kernel.org/r/20250611020229.2650595-1-rdunlap@infradead.org Signed-off-by: Greg Kroah-Hartman

vt: add missing notification when switching back to text mode

2025-06-19T11:27:16Z

Programs using poll() on /dev/vcsa to be notified when VT changes occur were missing one case: the switch from gfx to text mode. Signed-off-by: Nicolas Pitre Link: https://lore.kernel.org/r/9o5ro928-0pp4-05rq-70p4-ro385n21n723@onlyvoer.pbz Signed-off-by: Greg Kroah-Hartman

treewide, timers: Rename from_timer() to timer_container_of()

2025-06-08T07:07:37Z

Move this API to the canonical timer_*() namespace. [ tglx: Redone against pre rc1 ] Signed-off-by: Ingo Molnar Signed-off-by: Thomas Gleixner Link: https://lore.kernel.org/all/aB2X0jCKQO56WdMt@gmail.com

tty: serial: 8250_omap: fix TX with DMA for am33xx

2025-05-22T05:50:45Z

Commit 1788cf6a91d9 ("tty: serial: switch from circ_buf to kfifo") introduced an error in the TX DMA handling for 8250_omap. When the OMAP_DMA_TX_KICK flag is set, the "skip_byte" is pulled from the kfifo and emitted directly in order to start the DMA. While the kfifo is updated, dma->tx_size is not decreased. This leads to uart_xmit_advance() called in omap_8250_dma_tx_complete() advancing the kfifo by one too much. In practice, transmitting N bytes has been seen to result in the last N-1 bytes being sent repeatedly. This change fixes the problem by moving all of the dma setup after the OMAP_DMA_TX_KICK handling and using kfifo_len() instead of the DMA size for the 4-byte cutoff check. This slightly changes the behaviour at buffer wraparound, but it still transmits the correct bytes somehow. Now, the "skip_byte" would no longer be accounted to the stats. As previously, dma->tx_size included also this skip byte, up->icount.tx was updated by aforementioned uart_xmit_advance() in omap_8250_dma_tx_complete(). Fix this by using the uart_fifo_out() helper instead of bare kfifo_get(). Based on patch by Mans Rullgard Signed-off-by: "Jiri Slaby (SUSE)" Fixes: 1788cf6a91d9 ("tty: serial: switch from circ_buf to kfifo") Link: https://lore.kernel.org/all/20250506150748.3162-1-mans@mansr.com/ Reported-by: Mans Rullgard Cc: stable@vger.kernel.org Link: https://lore.kernel.org/r/20250522053835.3495975-1-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

vt: add VT_GETCONSIZECSRPOS to retrieve console size and cursor position

2025-05-21T11:41:03Z

The console dimension and cursor position are available through the /dev/vcsa interface already. However the /dev/vcsa header format uses single-byte fields therefore those values are clamped to 255. As surprizing as this may seem, some people do use 240-column 67-row screens (a 1920x1080 monitor with 8x16 pixel fonts) which is getting close to the limit. Monitors with higher resolution are not uncommon these days (3840x2160 producing a 480x135 character display) and it is just a matter of time before someone with, say, a braille display using the Linux VT console and BRLTTY on such a screen reports a bug about missing and oddly misaligned screen content. Let's add VT_GETCONSIZECSRPOS for the retrieval of console size and cursor position without byte-sized limitations. The actual console size limit as encoded in vt.c is 32767x32767 so using a short here is appropriate. Then this can be used to get the cursor position when /dev/vcsa reports 255. The screen dimension may already be obtained using TIOCGWINSZ and adding the same information to VT_GETCONSIZECSRPOS might be redundant. However applications that care about cursor position also care about display size and having 2 separate system calls to obtain them separately is wasteful. Also, the cursor position can be queried by writing "\e[6n" to a tty and reading back the result but that may be done only by the actual application using that tty and not a sideline observer. Signed-off-by: Nicolas Pitre Link: https://lore.kernel.org/r/20250520171851.1219676-3-nico@fluxnic.net Signed-off-by: Greg Kroah-Hartman

vt: bracketed paste support

2025-05-21T11:41:03Z

This is comprised of 3 aspects: - Take note of when applications advertise bracketed paste support via "\e[?2004h" and "\e[?2004l". - Insert bracketed paste markers ("\e[200~" and "\e[201~") around pasted content in paste_selection() when bracketed paste is active. - Add TIOCL_GETBRACKETEDPASTE to return bracketed paste status so user space daemons implementing cut-and-paste functionality (e.g. gpm, BRLTTY) may know when to insert bracketed paste markers. Link: https://en.wikipedia.org/wiki/Bracketed-paste Signed-off-by: Nicolas Pitre Reviewed-by: Jiri Slaby Link: https://lore.kernel.org/r/20250520171851.1219676-2-nico@fluxnic.net Signed-off-by: Greg Kroah-Hartman