kernel/linux.git/drivers/tty/serdev/serdev-ttyport.c, branch v6.19.11

tty: serdev: drop serdev_controller_ops::write_room()

2025-03-20T15:00:51+00:00

In particular, serdev_device_write_room() is not called, so the whole serdev's write_room() can go. Signed-off-by: Jiri Slaby (SUSE) Cc: Rob Herring Link: https://lore.kernel.org/r/20250317070046.24386-17-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

treewide, serdev: change receive_buf() return type to size_t

2024-01-28T02:13:53+00:00

receive_buf() is called from ttyport_receive_buf() that expects values ">= 0" from serdev_controller_receive_buf(), change its return type from ssize_t to size_t. The need for this clean-up was noticed while fixing a warning, see commit 94d053942544 ("Bluetooth: btnxpuart: fix recv_buf() return value"). Changing the callback prototype to return an unsigned seems the best way to document the API and ensure that is properly used. GNSS drivers implementation of serdev receive_buf() callback return directly the return value of gnss_insert_raw(). gnss_insert_raw() returns a signed int, however this is not an issue since the value returned is always positive, because of the kfifo_in() implementation. gnss_insert_raw() could be changed to return also an unsigned, however this is not implemented here as request by the GNSS maintainer Johan Hovold. Suggested-by: Jiri Slaby Link: https://lore.kernel.org/all/087be419-ec6b-47ad-851a-5e1e3ea5cfcc@kernel.org/ Signed-off-by: Francesco Dolcini Acked-by: Jonathan Cameron #for-iio Reviewed-by: Johan Hovold Reviewed-by: Rob Herring Reviewed-by: Alex Elder Acked-by: Maximilian Luz # for platform/surface Acked-by: Lee Jones Acked-by: Ilpo Järvinen Link: https://lore.kernel.org/r/20240122180551.34429-1-francesco@dolcini.it Signed-off-by: Greg Kroah-Hartman

tty: serdev: convert to u8 and size_t in serdev_controller_ops

2023-12-08T11:02:38+00:00

Switch character types to u8 and sizes to size_t. To conform to characters/sizes in the rest of the tty layer. In this patch, only struct serdev_controller_ops hooks. The rest will follow. Signed-off-by: "Jiri Slaby (SUSE)" Cc: Rob Herring Link: https://lore.kernel.org/r/20231206073712.17776-23-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

serial: core: Move tty and serdev to be children of serial core port device

2023-11-25T07:23:16+00:00

Let's move tty and serdev controller to be children of the serial core port device. This way the runtime PM usage count of a child device propagates to the serial hardware device. The tty and serdev devices are associated with a specific serial port of a serial hardware controller device, and we now have serial core hierarchy of controllers and ports. The tty device moves happily with just a change of the parent device and update of device_find_child() handling. The serdev device init needs some changes to separate the serial hardware controller device from the parent device. With this change the tty devices move under sysfs similar to this x86_64 qemu example of a diff of "find /sys -name ttyS*": /sys/class/tty/ttyS0 /sys/class/tty/ttyS3 /sys/class/tty/ttyS1 -/sys/devices/pnp0/00:04/tty/ttyS0 -/sys/devices/platform/serial8250/tty/ttyS2 -/sys/devices/platform/serial8250/tty/ttyS3 -/sys/devices/platform/serial8250/tty/ttyS1 +/sys/devices/pnp0/00:04/00:04:0/00:04:0.0/tty/ttyS0 +/sys/devices/platform/serial8250/serial8250:0/serial8250:0.3/tty/ttyS3 +/sys/devices/platform/serial8250/serial8250:0/serial8250:0.1/tty/ttyS1 +/sys/devices/platform/serial8250/serial8250:0/serial8250:0.2/tty/ttyS2 If a serdev device is used instead of a tty, it moves in a similar way. Suggested-by: Johan Hovold Cc: Maximilian Luz Cc: Rob Herring Signed-off-by: Tony Lindgren Link: https://lore.kernel.org/r/20231113080758.30346-1-tony@atomide.com Signed-off-by: Greg Kroah-Hartman

tty: make counts in tty_port_client_operations hooks size_t

2023-08-11T19:12:44+00:00

The counts in tty_port_client_operations hooks' are currently represented by all 'int', 'unsigned int', and 'size_t'. Unify them all to unsigned 'size_t' for clarity. Note that size_t is used already in tty_buffer.c. So, eventually, it is spread for counts everywhere and this is the beginning. So the two changes namely: * ::receive_buf() is called from tty_ldisc_receive_buf(). And that expects values ">= 0" from ::receive_buf(), so switch its rettype to size_t is fine. tty_ldisc_receive_buf() types will be changed separately. * ::lookahead_buf()'s count comes from lookahead_bufs() and is already 'unsigned int'. Signed-off-by: "Jiri Slaby (SUSE)" Cc: Rob Herring Link: https://lore.kernel.org/r/20230810091510.13006-11-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

tty: make tty_port_client_operations operate with u8

2023-08-11T19:12:44+00:00

The parameters are already unsigned chars. So make them explicitly u8s, as the rest is going to be unified to u8 eventually too. Signed-off-by: "Jiri Slaby (SUSE)" Cc: Rob Herring Link: https://lore.kernel.org/r/20230810091510.13006-10-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

serdev: Add method to assert break signal over tty UART port

2023-04-24T04:51:25+00:00

Adds serdev_device_break_ctl() and an implementation for ttyport. This function simply calls the break_ctl in tty layer, which can assert a break signal over UART-TX line, if the tty and the underlying platform and UART peripheral supports this operation. Signed-off-by: Neeraj Sanjay Kale Reviewed-by: Simon Horman Signed-off-by: Luiz Augusto von Dentz

serdev: Replace all instances of ENOTSUPP with EOPNOTSUPP

2023-04-24T04:51:11+00:00

This replaces all instances of ENOTSUPP with EOPNOTSUPP since ENOTSUPP is not a standard error code. This will help maintain consistency in error codes when new serdev API's are added. Signed-off-by: Neeraj Sanjay Kale Reviewed-by: Simon Horman Signed-off-by: Luiz Augusto von Dentz

serdev: ttyport: restore client ops on deregistration

2020-02-10T20:26:44+00:00

The serdev tty-port controller driver should reset the tty-port client operations also on deregistration to avoid a NULL-pointer dereference in case the port is later re-registered as a normal tty device. Note that this can only happen with tty drivers such as 8250 which have statically allocated port structures that can end up being reused and where a later registration would not register a serdev controller (e.g. due to registration errors or if the devicetree has been changed in between). Specifically, this can be an issue for any statically defined ports that would be registered by 8250 core when an 8250 driver is being unbound. Fixes: bed35c6dfa6a ("serdev: add a tty port controller driver") Cc: stable # 4.11 Reported-by: Loic Poulain Signed-off-by: Johan Hovold Link: https://lore.kernel.org/r/20200210145730.22762-1-johan@kernel.org Signed-off-by: Greg Kroah-Hartman

serdev: ttyport: call tiocmget and tiocmset ops directly

2019-01-30T10:48:08+00:00

The tty struct holds a pointer to the driver's tty operations so drop the unnecessary driver dereference when calling tiocmget and tiocmset. Note that this also makes the calls match the preceding sanity checks as expected. Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman