kernel/linux.git/drivers/tty/serial/ucc_uart.c, branch v6.12.80

tty: serial: switch from circ_buf to kfifo

2024-04-09T13:28:03+00:00

Switch from struct circ_buf to proper kfifo. kfifo provides much better API, esp. when wrap-around of the buffer needs to be taken into account. Look at pl011_dma_tx_refill() or cpm_uart_tx_pump() changes for example. Kfifo API can also fill in scatter-gather DMA structures, so it easier for that use case too. Look at lpuart_dma_tx() for example. Note that not all drivers can be converted to that (like atmel_serial), they handle DMA specially. Note that usb-serial uses kfifo for TX for ages. omap needed a bit more care as it needs to put a char into FIFO to start the DMA transfer when OMAP_DMA_TX_KICK is set. In that case, we have to do kfifo_dma_out_prepare twice: once to find out the tx_size (to find out if it is worths to do DMA at all -- size >= 4), the second time for the actual transfer. All traces of circ_buf are removed from serial_core.h (and its struct uart_state). Signed-off-by: Jiri Slaby (SUSE) Cc: Al Cooper Cc: Matthias Brugger Cc: AngeloGioacchino Del Regno Cc: Kumaravel Thiagarajan Cc: Tharun Kumar P Cc: Russell King Cc: Vineet Gupta Cc: Richard Genoud Cc: Nicolas Ferre Cc: Alexandre Belloni Cc: Claudiu Beznea Cc: Alexander Shiyan Cc: Baruch Siach Cc: Maciej W. Rozycki Cc: Shawn Guo Cc: Sascha Hauer Cc: Fabio Estevam Cc: Neil Armstrong Cc: Kevin Hilman Cc: Jerome Brunet Cc: Martin Blumenstingl Cc: Taichi Sugaya Cc: Takao Orito Cc: Bjorn Andersson Cc: Konrad Dybcio Cc: Pali Rohár Cc: Michael Ellerman Cc: Nicholas Piggin Cc: Christophe Leroy Cc: Aneesh Kumar K.V Cc: Naveen N. Rao Cc: Manivannan Sadhasivam Cc: Krzysztof Kozlowski Cc: Alim Akhtar Cc: Laxman Dewangan Cc: Thierry Reding Cc: Jonathan Hunter Cc: Orson Zhai Cc: Baolin Wang Cc: Chunyan Zhang Cc: Patrice Chotard Cc: Maxime Coquelin Cc: Alexandre Torgue Cc: David S. Miller Cc: Hammer Hsieh Cc: Peter Korsgaard Cc: Timur Tabi Cc: Michal Simek Cc: Sumit Semwal Cc: Christian König Link: https://lore.kernel.org/r/20240405060826.2521-13-jirislaby@kernel.org Signed-off-by: Greg Kroah-Hartman

serial: ucc_uart: Fix multiple address space type errors

2023-12-08T11:02:37+00:00

sparse reports multiple problems with address space type. Most problems are linked to missing __iomem qualifier. Others are caused by dereferencing __iomem addresses. Fix all this by adding missing __iomem and using ioread32be(). Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202312050412.zN2PKArS-lkp@intel.com/ Signed-off-by: Christophe Leroy Link: https://lore.kernel.org/r/e49deeb079391ff7273ec32f5563df94cf70bc95.1701781976.git.christophe.leroy@csgroup.eu Signed-off-by: Greg Kroah-Hartman

serial: ucc: Convert to platform remove callback returning void

2023-11-23T19:12:35+00:00

The .remove() callback for a platform driver returns an int which makes many driver authors wrongly assume it's possible to do error handling by returning an error code. However the value returned is ignored (apart from emitting a warning) and this typically results in resource leaks. To improve here there is a quest to make the remove callback return void. In the first step of this quest all drivers are converted to .remove_new(), which already returns void. Eventually after all drivers are converted, .remove_new() will be renamed to .remove(). Trivially convert this driver from always returning zero in the remove callback to the void returning variant. Signed-off-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20231110152927.70601-52-u.kleine-koenig@pengutronix.de Signed-off-by: Greg Kroah-Hartman

serial: ucc_uart: Use port lock wrappers

2023-09-18T09:18:16+00:00

When a serial port is used for kernel console output, then all modifications to the UART registers which are done from other contexts, e.g. getty, termios, are interference points for the kernel console. So far this has been ignored and the printk output is based on the principle of hope. The rework of the console infrastructure which aims to support threaded and atomic consoles, requires to mark sections which modify the UART registers as unsafe. This allows the atomic write function to make informed decisions and eventually to restore operational state. It also allows to prevent the regular UART code from modifying UART registers while printk output is in progress. All modifications of UART registers are guarded by the UART port lock, which provides an obvious synchronization point with the console infrastructure. To avoid adding this functionality to all UART drivers, wrap the spin_[un]lock*() invocations for uart_port::lock into helper functions which just contain the spin_[un]lock*() invocations for now. In a subsequent step these helpers will gain the console synchronization mechanisms. Converted with coccinelle. No functional change. Signed-off-by: Thomas Gleixner Acked-by: Timur Tabi Signed-off-by: John Ogness Link: https://lore.kernel.org/r/20230914183831.587273-73-john.ogness@linutronix.de Signed-off-by: Greg Kroah-Hartman

serial: cpm_uart: Don't include fs_uart_pd.h when not needed

2023-08-04T13:08:55+00:00

Remove inclusion of fs_uart_pd.h from all files not using anything from that file. Signed-off-by: Christophe Leroy Link: https://lore.kernel.org/r/c7996ef4de56e7ee42a434e37d214cba337a146c.1691068700.git.christophe.leroy@csgroup.eu Signed-off-by: Greg Kroah-Hartman

Merge 6.5-rc4 into tty-next

2023-07-31T07:39:56+00:00

We need the serial/tty fixes in here as well for testing and future development. Signed-off-by: Greg Kroah-Hartman

tty: Explicitly include correct DT includes

2023-07-25T18:19:05+00:00

The DT of_device.h and of_platform.h date back to the separate of_platform_bus_type before it as merged into the regular platform bus. As part of that merge prepping Arm DT support 13 years ago, they "temporarily" include each other. They also include platform_device.h and of.h. As a result, there's a pretty much random mix of those include files used throughout the tree. In order to detangle these headers and replace the implicit includes with struct declarations, users need to explicitly include the correct includes. Signed-off-by: Rob Herring Acked-by: Uwe Kleine-König # for imx Link: https://lore.kernel.org/r/20230724205440.767071-1-robh@kernel.org Signed-off-by: Greg Kroah-Hartman

Documentation: devices.txt: reconcile serial/ucc_uart minor numers

2023-07-25T17:29:23+00:00

Reconcile devices.txt with serial/ucc_uart.c regarding device number assignments. ucc_uart.c supports 4 ports and uses minor devnums 46-49, so update devices.txt with that info. Then update ucc_uart.c's reference to the location of the devices.txt list in the kernel source tree. Fixes: d7584ed2b994 ("[POWERPC] qe-uart: add support for Freescale QUICCEngine UART") Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2") Signed-off-by: Randy Dunlap Cc: Timur Tabi Cc: Kumar Gala Cc: linuxppc-dev@lists.ozlabs.org Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: linux-serial@vger.kernel.org Cc: Jonathan Corbet Cc: linux-doc@vger.kernel.org Link: https://lore.kernel.org/r/20230724063341.28198-1-rdunlap@infradead.org Signed-off-by: Greg Kroah-Hartman

serial: ucc_uart: Use uart_circ_empty()

2023-03-29T08:53:57+00:00

Use uart_circ_empty() rather than open coding it. Signed-off-by: Ilpo Järvinen Link: https://lore.kernel.org/r/20230320135009.47170-1-ilpo.jarvinen@linux.intel.com Signed-off-by: Greg Kroah-Hartman

serial: Use of_property_read_bool() for boolean properties

2023-03-16T12:02:14+00:00

It is preferred to use typed property access functions (i.e. of_property_read_ functions) rather than low-level of_get_property/of_find_property functions for reading properties. Convert reading boolean properties to to of_property_read_bool(). Signed-off-by: Rob Herring Acked-by: Uwe Kleine-König Link: https://lore.kernel.org/r/20230310144727.1545699-1-robh@kernel.org Signed-off-by: Greg Kroah-Hartman