kernel/linux.git/include/linux/spi/spi.h, branch v5.15.97

spi: Fix deadlock when adding SPI controllers on SPI buses

2021-10-14T11:47:29+00:00

Currently we have a global spi_add_lock which we take when adding new devices so that we can check that we're not trying to reuse a chip select that's already controlled. This means that if the SPI device is itself a SPI controller and triggers the instantiation of further SPI devices we trigger a deadlock as we try to register and instantiate those devices while in the process of doing so for the parent controller and hence already holding the global spi_add_lock. Since we only care about concurrency within a single SPI bus move the lock to be per controller, avoiding the deadlock. This can be easily triggered in the case of spi-mux. Reported-by: Uwe Kleine-König Signed-off-by: Mark Brown

spi: modify set_cs_timing parameter

2021-08-05T15:42:54+00:00

This patch modified set_cs_timing parameter, no need pass in spi_delay to set_cs_timing callback. By the way, we modified the mediatek and tegra114 spi driver to fix build err. In mediatek spi driver, We have support set absolute time not clk_count, and call this function in prepare_message not user's API. Signed-off-by: Mason Zhang Link: https://lore.kernel.org/r/20210804133746.6742-1-Mason.Zhang@mediatek.com Signed-off-by: Mark Brown

spi: move cs spi_delay to spi_device

2021-08-05T15:42:53+00:00

As we know, spi core layer has removed spi_set_cs_timing() API. So this patch moved spi_delay for cs_timing from spi_controller to spi_device, because cs timing should be set by spi_device but not controller. Signed-off-by: Mason Zhang Link: https://lore.kernel.org/r/20210804133716.32040-1-Mason.Zhang@mediatek.com Signed-off-by: Mark Brown

spi: : add missing struct kernel-doc entry

2021-07-11T22:51:44+00:00

Fix kernel-doc warning in spi.h by adding the missing kernel-doc entry and also correct the original comment so that they both indicate the correct polarity of the flag. ../include/linux/spi/spi.h:673: warning: Function parameter or member 'devm_allocated' not described in 'spi_controller' Fixes: 794aaf01444d ("spi: Fix use-after-free with devm_spi_alloc_*") Signed-off-by: Randy Dunlap Cc: William A. Kennington III Cc: Mark Brown Cc: linux-spi@vger.kernel.org Cc: Lukas Wunner Reviewed-by: Lukas Wunner Link: https://lore.kernel.org/r/20210628210520.5712-1-rdunlap@infradead.org Signed-off-by: Mark Brown

spi: core: add dma_map_dev for dma device

2021-06-25T11:26:49+00:00

Some controllers like qcom geni need the parent device to be used for dma mapping, so add a dma_map_dev field and let drivers fill this to be used as mapping device Signed-off-by: Vinod Koul Link: https://lore.kernel.org/r/20210625052213.32260-4-vkoul@kernel.org Signed-off-by: Mark Brown

spi: add ancillary device support

2021-06-22T11:54:59+00:00

Introduce support for ancillary devices, similar to existing implementation for I2C. This is useful for devices having multiple chip-selects, for example some microcontrollers provide a normal SPI interface and a flashing SPI interface. Signed-off-by: Sebastian Reichel Link: https://lore.kernel.org/r/20210621175359.126729-2-sebastian.reichel@collabora.com Signed-off-by: Mark Brown

spi: remove spi_set_cs_timing()

2021-06-09T10:55:46+00:00

No one seems to be using this global and exported function, so remove it as it is no longer needed. Cc: Mark Brown Signed-off-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/20210609071918.2852069-1-gregkh@linuxfoundation.org Signed-off-by: Mark Brown

spi: Switch to signed types for *_native_cs SPI controller fields

2021-05-11T09:05:40+00:00

While fixing undefined behaviour the commit f60d7270c8a3 ("spi: Avoid undefined behaviour when counting unused native CSs") missed the case when all CSs are GPIOs and thus unused_native_cs will be evaluated to -1 in unsigned representation. This will falsely trigger a condition in the spi_get_gpio_descs(). Switch to signed types for *_native_cs SPI controller fields to fix above. Fixes: f60d7270c8a3 ("spi: Avoid undefined behaviour when counting unused native CSs") Signed-off-by: Andy Shevchenko Link: https://lore.kernel.org/r/20210510131242.49455-1-andriy.shevchenko@linux.intel.com Signed-off-by: Mark Brown

Merge branch 'for-5.12' of https://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi into spi-5.13

2021-04-15T18:29:40+00:00

spi: Fix use-after-free with devm_spi_alloc_*

2021-04-08T14:08:53+00:00

We can't rely on the contents of the devres list during spi_unregister_controller(), as the list is already torn down at the time we perform devres_find() for devm_spi_release_controller. This causes devices registered with devm_spi_alloc_{master,slave}() to be mistakenly identified as legacy, non-devm managed devices and have their reference counters decremented below 0. ------------[ cut here ]------------ WARNING: CPU: 1 PID: 660 at lib/refcount.c:28 refcount_warn_saturate+0x108/0x174 [] (refcount_warn_saturate) from [] (kobject_put+0x90/0x98) [] (kobject_put) from [] (put_device+0x20/0x24) r4:b6700140 [] (put_device) from [] (devm_spi_release_controller+0x3c/0x40) [] (devm_spi_release_controller) from [] (release_nodes+0x84/0xc4) r5:b6700180 r4:b6700100 [] (release_nodes) from [] (devres_release_all+0x5c/0x60) r8:b1638c54 r7:b117ad94 r6:b1638c10 r5:b117ad94 r4:b163dc10 [] (devres_release_all) from [] (__device_release_driver+0x144/0x1ec) r5:b117ad94 r4:b163dc10 [] (__device_release_driver) from [] (device_driver_detach+0x84/0xa0) r9:00000000 r8:00000000 r7:b117ad94 r6:b163dc54 r5:b1638c10 r4:b163dc10 [] (device_driver_detach) from [] (unbind_store+0xe4/0xf8) Instead, determine the devm allocation state as a flag on the controller which is guaranteed to be stable during cleanup. Fixes: 5e844cc37a5c ("spi: Introduce device-managed SPI controller allocation") Signed-off-by: William A. Kennington III Link: https://lore.kernel.org/r/20210407095527.2771582-1-wak@google.com Signed-off-by: Mark Brown