kernel/linux.git/Documentation/spi, branch v6.12.80

spi: Enable controllers to extend the SPI protocol with MOSI idle configuration

2024-07-29T00:19:51+00:00

The behavior of an SPI controller data output line (SDO or MOSI or COPI (Controller Output Peripheral Input) for disambiguation) is usually not specified when the controller is not clocking out data on SCLK edges. However, there do exist SPI peripherals that require specific MOSI line state when data is not being clocked out of the controller. Conventional SPI controllers may set the MOSI line on SCLK edges then bring it low when no data is going out or leave the line the state of the last transfer bit. More elaborated controllers are capable to set the MOSI idle state according to different configurable levels and thus are more suitable for interfacing with demanding peripherals. Add SPI mode bits to allow peripherals to request explicit MOSI idle state when needed. When supporting a particular MOSI idle configuration, the data output line state is expected to remain at the configured level when the controller is not clocking out data. When a device that needs a specific MOSI idle state is identified, its driver should request the MOSI idle configuration by setting the proper SPI mode bit. Acked-by: Nuno Sa Reviewed-by: Jonathan Cameron Reviewed-by: David Lechner Tested-by: David Lechner Signed-off-by: Marcelo Schmitt Link: https://patch.msgid.link/9802160b5e5baed7f83ee43ac819cb757a19be55.1720810545.git.marcelo.schmitt@analog.com Signed-off-by: Mark Brown

spi: pxa2xx: Drop the stale entry in documentation TOC

2024-05-07T14:53:21+00:00

The documentation had been removed, so should TOC entry. Reported-by: Stephen Rothwell Fixes: 2d069c11e822 ("spi: pxa2xx: Remove outdated documentation") Signed-off-by: Andy Shevchenko Closes: https://lore.kernel.org/r/20240507163131.183813ee@canb.auug.org.au Link: https://lore.kernel.org/r/20240507132002.71938-1-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown

spi: pxa2xx: Remove outdated documentation

2024-05-03T02:11:34+00:00

The documentation is referring to the legacy enumeration of the SPI host controllers and target devices. It has nothing to do with the modern way, which is the only supported in kernel right now. Hence, remove outdated documentation file. Signed-off-by: Andy Shevchenko Reviewed-by: Linus Walleij Link: https://lore.kernel.org/r/20240417110334.2671228-5-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown

spi: docs: drop driver owner initialization

2024-04-02T14:55:35+00:00

Core in spi_register_driver() already sets the .owner, so driver does not need to. Signed-off-by: Krzysztof Kozlowski Link: https://msgid.link/r/20240328203927.156184-1-krzysztof.kozlowski@linaro.org Signed-off-by: Mark Brown

spi: pxa2xx: Clean up linux/spi/pxa2xx_spi.h

2024-03-26T11:46:40+00:00

Merge series from Andy Shevchenko : A couple of cleanups against linux/spi/pxa2xx_spi.h. I'm sending this as v3 to land in the SPI subsystem. Meanwhile I'm preparing an update to make linux/spi/pxa2xx_spi.h private to the subsystem (PXA2xx driver). But the second part will be presented later on (likely after v6.9-rc1). That said, this can be routed either via SoC tree or SPI, up to respective maintainers.

spi: remove struct spi_message::is_dma_mapped

2024-03-25T20:30:07+00:00

There are no more users of the deprecated is_dma_mapped in struct spi_message so it can be removed. References in documentation and comments are also removed. A few similar checks if xfer->tx_dma or xfer->rx_dma are not NULL are also removed since these are now guaranteed to be NULL because they were previously set only if is_dma_mapped was true. Signed-off-by: David Lechner Link: https://msgid.link/r/20240325-spi-remove-is_dma_mapped-v2-1-d08d62b61f1c@baylibre.com Signed-off-by: Mark Brown

spi: pxa2xx: Make num_chipselect 8-bit in the struct pxa2xx_spi_controller

2024-03-25T00:49:16+00:00

There is no use for whole 16-bit for the number of chip select pins. Drop it to 8 bits. Acked-by: Arnd Bergmann Signed-off-by: Andy Shevchenko Link: https://msgid.link/r/20240307195056.4059864-3-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown

spi: docs: spidev: fix echo command format

2024-03-19T18:37:55+00:00

The two example echo commands for binding the spidev driver were being rendered as one line in the HTML output. This patch makes use of the restructured text :: to format the commands as a code block instead which preserves the line break. Signed-off-by: David Lechner Link: https://msgid.link/r/20240319183344.2106335-1-dlechner@baylibre.com Signed-off-by: Mark Brown

spi: lm70llp: fix links in doc and comments

2024-03-18T15:55:12+00:00

Update links in the documentation and in-code comments which point to the datasheet and schematic. The current links don't work because National Semiconductor (which is the manufacturer of this board and lm70) has been a part of Texas Instruments since 2011 and hence http://www.national.com/ doesn't work anymore. Fixes: 78961a574037 ("spi_lm70llp parport adapter driver") Fixes: 2b7300513b98 ("hwmon: (lm70) Code streamlining and cleanup") Signed-off-by: Kousik Sanagavarapu Link: https://msgid.link/r/20240318154540.90613-2-five231003@gmail.com Signed-off-by: Mark Brown

spi: spi-summary.rst: fix underline length

2024-02-19T13:21:58+00:00

The change to use "target" requires an underline to be extended by one more character to fix a documentation build warning: Documentation/spi/spi-summary.rst:274: WARNING: Title underline too short. Declare target Devices ^^^^^^^^^^^^^^^^^^^^^ Fixes: hash ("spi: Update the "master/slave" terminology in documentation") Signed-off-by: Randy Dunlap Cc: Dhruva Gole Cc: Mark Brown Cc: linux-spi@vger.kernel.org Reviewed-by: Dhruva Gole Link: https://msgid.link/r/20240216051637.10920-1-rdunlap@infradead.org Signed-off-by: Mark Brown