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2024-07-20Merge tag 'char-misc-6.11-rc1' of ↵Linus Torvalds1-36/+54
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc Pull char / misc and other driver updates from Greg KH: "Here is the "big" set of char/misc and other driver subsystem changes for 6.11-rc1. Nothing major in here, just loads of new drivers and updates. Included in here are: - IIO api updates and new drivers added - wait_interruptable_timeout() api cleanups for some drivers - MODULE_DESCRIPTION() additions for loads of drivers - parport out-of-bounds fix - interconnect driver updates and additions - mhi driver updates and additions - w1 driver fixes - binder speedups and fixes - eeprom driver updates - coresight driver updates - counter driver update - new misc driver additions - other minor api updates All of these, EXCEPT for the final Kconfig build fix for 32bit systems, have been in linux-next for a while with no reported issues. The Kconfig fixup went in 29 hours ago, so might have missed the latest linux-next, but was acked by everyone involved" * tag 'char-misc-6.11-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (330 commits) misc: Kconfig: exclude mrvl-cn10k-dpi compilation for 32-bit systems misc: delete Makefile.rej binder: fix hang of unregistered readers misc: Kconfig: add a new dependency for MARVELL_CN10K_DPI virtio: add missing MODULE_DESCRIPTION() macro agp: uninorth: add missing MODULE_DESCRIPTION() macro spmi: add missing MODULE_DESCRIPTION() macros dev/parport: fix the array out-of-bounds risk samples: configfs: add missing MODULE_DESCRIPTION() macro misc: mrvl-cn10k-dpi: add Octeon CN10K DPI administrative driver misc: keba: Fix missing AUXILIARY_BUS dependency slimbus: Fix struct and documentation alignment in stream.c MAINTAINERS: CC dri-devel list on Qualcomm FastRPC patches misc: fastrpc: use coherent pool for untranslated Compute Banks misc: fastrpc: support complete DMA pool access to the DSP misc: fastrpc: add missing MODULE_DESCRIPTION() macro misc: fastrpc: Add missing dev_err newlines misc: fastrpc: Use memdup_user() nvmem: core: Implement force_ro sysfs attribute nvmem: Use sysfs_emit() for type attribute ...
2024-07-05nvmem: core: Implement force_ro sysfs attributeMarek Vasut1-0/+43
Implement "force_ro" sysfs attribute to allow users to set read-write devices as read-only and back to read-write from userspace. The choice of the name is based on MMC core 'force_ro' attribute. This solves a situation where an AT24 I2C EEPROM with GPIO based nWP signal may have to be occasionally updated. Such I2C EEPROM device is usually set as read-only during most of the regular system operation, but in case it has to be updated in a controlled manner, it could be unlocked using this new "force_ro" sysfs attribute and then re-locked again. The "read-only" DT property and config->read_only configuration is respected and is used to set default state of the device, read-only or read-write, for devices which do implement .reg_write function. For devices which do not implement .reg_write function, the device is unconditionally read-only and the "force_ro" attribute is not visible. Signed-off-by: Marek Vasut <marex@denx.de> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20240705074852.423202-16-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05nvmem: Use sysfs_emit() for type attributeMarek Vasut1-1/+1
Use sysfs_emit() instead of sprintf() to follow best practice per Documentation/filesystems/sysfs.rst " show() should only use sysfs_emit()... " Signed-off-by: Marek Vasut <marex@denx.de> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20240705074852.423202-15-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05nvmem: core: drop unnecessary range checks in sysfs callbacksThomas Weißschuh1-14/+0
The same checks have already been done in sysfs_kf_bin_write() and sysfs_kf_bin_read() just before the callbacks are invoked. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20240705074852.423202-12-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05nvmem: core: remove global nvmem_cells_groupThomas Weißschuh1-16/+10
nvmem_cells_groups is a global variable that is also mutated. This is complicated and error-prone. Instead use a normal stack variable. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20240705074852.423202-11-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-05nvmem: core: add single sysfs groupThomas Weißschuh1-6/+1
The sysfs core provides a function to easily register a single group. Use it and remove the now unnecessary nvmem_cells_groups array. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20240705074852.423202-10-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-03nvmem: core: limit cell sysfs permissions to main attribute onesThomas Weißschuh1-1/+1
The cell sysfs attribute should not provide more access to the nvmem data than the main attribute itself. For example if nvme_config::root_only was set, the cell attribute would still provide read access to everybody. Mask out permissions not available on the main attribute. Fixes: 0331c611949f ("nvmem: core: Expose cells through sysfs") Cc: stable@vger.kernel.org Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20240628113704.13742-5-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-07-03nvmem: core: only change name to fram for current attributeThomas Weißschuh1-3/+2
bin_attr_nvmem_eeprom_compat is the template from which all future compat attributes are created. Changing it means to change all subsquent compat attributes, too. Instead only use the "fram" name for the currently registered attribute. Fixes: fd307a4ad332 ("nvmem: prepare basics for FRAM support") Cc: stable@vger.kernel.org Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20240628113704.13742-4-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-05-03nvmem: core: switch to use device_add_groups()Greg Kroah-Hartman1-1/+1
devm_device_add_groups() is being removed from the kernel, so move the nvmem driver to use device_add_groups() instead. The logic is identical, when the device is removed the driver core will properly clean up and remove the groups, and the memory used by the attribute groups will be freed because it was created with dev_* calls, so this is functionally identical overall. Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Link: https://lore.kernel.org/r/20240430084921.33387-7-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-03-07nvmem: core: Print error on wrong bits DT propertyMarkus Schneider-Pargmann1-0/+5
The algorithms in nvmem core are built with the constraint that bit_offset < 8. If bit_offset is greater the results are wrong. Print an error if the devicetree 'bits' property is outside of the valid range and abort parsing. Signed-off-by: Markus Schneider-Pargmann <msp@baylibre.com> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20240224114516.86365-12-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-02-14nvmem: include bit index in cell sysfs file nameArnd Bergmann1-2/+3
Creating sysfs files for all Cells caused a boot failure for linux-6.8-rc1 on Apple M1, which (in downstream dts files) has multiple nvmem cells that use the same byte address. This causes the device probe to fail with [ 0.605336] sysfs: cannot create duplicate filename '/devices/platform/soc@200000000/2922bc000.efuse/apple_efuses_nvmem0/cells/efuse@a10' [ 0.605347] CPU: 7 PID: 1 Comm: swapper/0 Tainted: G S 6.8.0-rc1-arnd-5+ #133 [ 0.605355] Hardware name: Apple Mac Studio (M1 Ultra, 2022) (DT) [ 0.605362] Call trace: [ 0.605365] show_stack+0x18/0x2c [ 0.605374] dump_stack_lvl+0x60/0x80 [ 0.605383] dump_stack+0x18/0x24 [ 0.605388] sysfs_warn_dup+0x64/0x80 [ 0.605395] sysfs_add_bin_file_mode_ns+0xb0/0xd4 [ 0.605402] internal_create_group+0x268/0x404 [ 0.605409] sysfs_create_groups+0x38/0x94 [ 0.605415] devm_device_add_groups+0x50/0x94 [ 0.605572] nvmem_populate_sysfs_cells+0x180/0x1b0 [ 0.605682] nvmem_register+0x38c/0x470 [ 0.605789] devm_nvmem_register+0x1c/0x6c [ 0.605895] apple_efuses_probe+0xe4/0x120 [ 0.606000] platform_probe+0xa8/0xd0 As far as I can tell, this is a problem for any device with multiple cells on different bits of the same address. Avoid the issue by changing the file name to include the first bit number. Fixes: 0331c611949f ("nvmem: core: Expose cells through sysfs") Link: https://github.com/AsahiLinux/linux/blob/bd0a1a7d4/arch/arm64/boot/dts/apple/t600x-dieX.dtsi#L156 Cc: <regressions@lists.linux.dev> Cc: Miquel Raynal <miquel.raynal@bootlin.com> Cc: Rafał Miłecki <rafal@milecki.pl> Cc: Chen-Yu Tsai <wenst@chromium.org> Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: <asahi@lists.linux.dev> Cc: Sven Peter <sven@svenpeter.dev> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Reviewed-by: Eric Curtin <ecurtin@redhat.com> Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/r/20240209163454.98051-1-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-04nvmem: core: add nvmem_dev_size() helperRafał Miłecki1-0/+13
This is required by layouts that need to read whole NVMEM content. It's especially useful for NVMEM devices without hardcoded layout (like U-Boot environment data block). Signed-off-by: Rafał Miłecki <rafal@milecki.pl> Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com> Link: https://lore.kernel.org/r/20231221173421.13737-2-zajec5@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-04nvmem: drop nvmem_layout_get_match_data()Rafał Miłecki1-13/+0
Thanks for layouts refactoring we now have "struct device" associated with layout. Also its OF pointer points directly to the "nvmem-layout" DT node. All it takes to get match data is a generic of_device_get_match_data(). Signed-off-by: Rafał Miłecki <rafal@milecki.pl> Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com> Reviewed-by: Michael Walle <michael@walle.cc> Link: https://lore.kernel.org/r/20231219120104.3422-2-zajec5@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2024-01-04nvmem: layouts: refactor .add_cells() callback argumentsRafał Miłecki1-1/+1
Simply pass whole "struct nvmem_layout" instead of single variables. There is nothing in "struct nvmem_layout" that we have to hide from layout drivers. They also access it during .probe() and .remove(). Thanks to this change: 1. API gets more consistent All layouts drivers callbacks get the same argument 2. Layouts get correct device Before this change NVMEM core code was passing NVMEM device instead of layout device. That resulted in: * Confusing prints * Calling devm_*() helpers on wrong device * Helpers like of_device_get_match_data() dereferencing NULLs 3. It gets possible to get match data First of all nvmem_layout_get_match_data() requires passing "struct nvmem_layout" which .add_cells() callback didn't have before this. It doesn't matter much as it's rather useless now anyway (and will be dropped). What's more important however is that of_device_get_match_data() can be used now thanks to owning a proper device pointer. Signed-off-by: Rafał Miłecki <rafal@milecki.pl> Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com> Reviewed-by: Michael Walle <michael@walle.cc> Link: https://lore.kernel.org/r/20231219120104.3422-1-zajec5@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-15nvmem: core: Expose cells through sysfsMiquel Raynal1-1/+134
The binary content of nvmem devices is available to the user so in the easiest cases, finding the content of a cell is rather easy as it is just a matter of looking at a known and fixed offset. However, nvmem layouts have been recently introduced to cope with more advanced situations, where the offset and size of the cells is not known in advance or is dynamic. When using layouts, more advanced parsers are used by the kernel in order to give direct access to the content of each cell, regardless of its position/size in the underlying device. Unfortunately, these information are not accessible by users, unless by fully re-implementing the parser logic in userland. Let's expose the cells and their content through sysfs to avoid these situations. Of course the relevant NVMEM sysfs Kconfig option must be enabled for this support to be available. Not all nvmem devices expose cells. Indeed, the .bin_attrs attribute group member will be filled at runtime only when relevant and will remain empty otherwise. In this case, as the cells attribute group will be empty, it will not lead to any additional folder/file creation. Exposed cells are read-only. There is, in practice, everything in the core to support a write path, but as I don't see any need for that, I prefer to keep the interface simple (and probably safer). The interface is documented as being in the "testing" state which means we can later add a write attribute if though relevant. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Tested-by: Rafał Miłecki <rafal@milecki.pl> Tested-by: Chen-Yu Tsai <wenst@chromium.org> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20231215111536.316972-9-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-15nvmem: core: Rework layouts to become regular devicesMiquel Raynal1-109/+61
Current layout support was initially written without modules support in mind. When the requirement for module support rose, the existing base was improved to adopt modularization support, but kind of a design flaw was introduced. With the existing implementation, when a storage device registers into NVMEM, the core tries to hook a layout (if any) and populates its cells immediately. This means, if the hardware description expects a layout to be hooked up, but no driver was provided for that, the storage medium will fail to probe and try later from scratch. Even if we consider that the hardware description shall be correct, we could still probe the storage device (especially if it contains the rootfs). One way to overcome this situation is to consider the layouts as devices, and leverage the native notifier mechanism. When a new NVMEM device is registered, we can populate its nvmem-layout child, if any, and wait for the matching to be done in order to get the cells (the waiting can be easily done with the NVMEM notifiers). If the layout driver is compiled as a module, it should automatically be loaded. This way, there is no strong order to enforce, any NVMEM device creation or NVMEM layout driver insertion will be observed as a new event which may lead to the creation of additional cells, without disturbing the probes with costly (and sometimes endless) deferrals. In order to achieve that goal we create a new bus for the nvmem-layouts with minimal logic to match nvmem-layout devices with nvmem-layout drivers. All this infrastructure code is created in the layouts.c file. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Tested-by: Rafał Miłecki <rafal@milecki.pl> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20231215111536.316972-7-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-15nvmem: Move and rename ->fixup_cell_info()Miquel Raynal1-3/+3
This hook is meant to be used by any provider and instantiating a layout just for this is useless. Let's instead move this hook to the nvmem device and add it to the config structure to be easily shared by the providers. While at moving this hook, rename it ->fixup_dt_cell_info() to clarify its main intended purpose. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20231215111536.316972-6-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-15nvmem: Simplify the ->add_cells() hookMiquel Raynal1-1/+1
The layout entry is not used and will anyway be made useless by the new layout bus infrastructure coming next, so drop it. While at it, clarify the kdoc entry. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20231215111536.316972-5-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-15nvmem: Create a header for internal sharingMiquel Raynal1-23/+1
Before adding all the NVMEM layout bus infrastructure to the core, let's move the main nvmem_device structure in an internal header, only available to the core. This way all the additional code can be added in a dedicated file in order to keep the current core file tidy. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20231215111536.316972-4-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-15nvmem: Move of_nvmem_layout_get_container() in another headerMiquel Raynal1-8/+0
nvmem-consumer.h is included by consumer devices, extracting data from NVMEM devices whereas nvmem-provider.h is included by devices providing NVMEM content. The only users of of_nvmem_layout_get_container() outside of the core are layout drivers, so better move its prototype to nvmem-provider.h. While we do so, we also move the kdoc associated with the function to the header rather than the .c file. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20231215111536.316972-3-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-12-07nvmem: Do not expect fixed layouts to grab a layout driverMiquel Raynal1-0/+6
Two series lived in parallel for some time, which led to this situation: - The nvmem-layout container is used for dynamic layouts - We now expect fixed layouts to also use the nvmem-layout container but this does not require any additional driver, the support is built-in the nvmem core. Ensure we don't refuse to probe for wrong reasons. Fixes: 27f699e578b1 ("nvmem: core: add support for fixed cells *layout*") Cc: stable@vger.kernel.org Reported-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Tested-by: Rafał Miłecki <rafal@milecki.pl> Tested-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Link: https://lore.kernel.org/r/20231124193814.360552-1-miquel.raynal@bootlin.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-27Revert "nvmem: add new config option"Rafał Miłecki1-1/+1
This reverts commit 517f14d9cf3533d5ab4fded195ab6f80a92e378f. Config option "no_of_node" is no longer needed since adding a more explicit and targeted option "add_legacy_fixed_of_cells". That "no_of_node" config option was needed *earlier* to help mtd's case. DT nodes of MTD partitions (that are also NVMEM devices) may contain subnodes. Those SHOULD NOT be treated as NVMEM fixed cells. To prevent NVMEM core code from parsing subnodes a "no_of_node" option was added (and set to true in mtd) to make for_each_child_of_node() in NVMEM a no-op. That was a bit hacky because it was messing with "of_node" pointer to achieve some side-effect. With the introduction of "add_legacy_fixed_of_cells" config option things got more explicit. MTD subsystem simply tells NVMEM when to look for fixed cells and there is no need to hack "of_node" pointer anymore. Signed-off-by: Rafał Miłecki <rafal@milecki.pl> Reviewed-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20231023102759.31529-1-zajec5@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-10-21nvmem: add explicit config option to read old syntax fixed OF cellsRafał Miłecki1-3/+5
Binding for fixed NVMEM cells defined directly as NVMEM device subnodes has been deprecated. It has been replaced by the "fixed-layout" NVMEM layout binding. New syntax is meant to be clearer and should help avoiding imprecise bindings. NVMEM subsystem already supports the new binding. It should be a good idea to limit support for old syntax to existing drivers that actually support & use it (we can't break backward compatibility!). That way we additionally encourage new bindings & drivers to ignore deprecated binding. It wasn't clear (to me) if rtc and w1 code actually uses old syntax fixed cells. I enabled them to don't risk any breakage. Signed-off-by: Rafał Miłecki <rafal@milecki.pl> [for meson-{efuse,mx-efuse}.c] Acked-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com> [for mtk-efuse.c, nvmem/core.c, nvmem-provider.h] Reviewed-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> [MT8192, MT8195 Chromebooks] Tested-by: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com> [for microchip-otpc.c] Reviewed-by: Claudiu Beznea <claudiu.beznea@microchip.com> [SAMA7G5-EK] Tested-by: Claudiu Beznea <claudiu.beznea@microchip.com> Acked-by: Jernej Skrabec <jernej.skrabec@gmail.com> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20231020105545.216052-3-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-23nvmem: core: Notify when a new layout is registeredMiquel Raynal1-0/+4
Tell listeners a new layout was introduced and is now available. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230823132744.350618-23-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-23nvmem: core: Do not open-code existing functionsMiquel Raynal1-2/+2
Use of_nvmem_layout_get_container() instead of hardcoding it. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Reviewed-by: Michael Walle <michael@walle.cc> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230823132744.350618-22-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-23nvmem: core: Create all cells before adding the nvmem deviceMiquel Raynal1-5/+5
Let's pack all the cells creation in one place, so they are all created before we add the nvmem device. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Reviewed-by: Michael Walle <michael@walle.cc> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230823132744.350618-20-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-23nvmem: Explicitly include correct DT includesRob Herring1-1/+0
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 <robh@kernel.org> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230823132744.350618-14-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-06-15nvmem: core: add support for fixed cells *layout*Rafał Miłecki1-3/+29
This adds support for the "fixed-layout" NVMEM layout binding. It allows defining NVMEM cells in a layout DT node named "nvmem-layout". While NVMEM subsystem supports layout drivers it has been discussed that "fixed-layout" may actually be supperted internally. It's because: 1. It's a very basic layout 2. It allows sharing code with legacy syntax parsing 3. It's safer for soc_device_match() due to -EPROBE_DEFER 4. This will make the syntax transition easier Signed-off-by: Rafał Miłecki <rafal@milecki.pl> Reviewed-by: Michael Walle <michael@walle.cc> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Message-ID: <20230611140330.154222-26-srinivas.kandagatla@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-28Merge tag 'modules-6.4-rc1' of ↵Linus Torvalds1-1/+0
git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux Pull module updates from Luis Chamberlain: "The summary of the changes for this pull requests is: - Song Liu's new struct module_memory replacement - Nick Alcock's MODULE_LICENSE() removal for non-modules - My cleanups and enhancements to reduce the areas where we vmalloc module memory for duplicates, and the respective debug code which proves the remaining vmalloc pressure comes from userspace. Most of the changes have been in linux-next for quite some time except the minor fixes I made to check if a module was already loaded prior to allocating the final module memory with vmalloc and the respective debug code it introduces to help clarify the issue. Although the functional change is small it is rather safe as it can only *help* reduce vmalloc space for duplicates and is confirmed to fix a bootup issue with over 400 CPUs with KASAN enabled. I don't expect stable kernels to pick up that fix as the cleanups would have also had to have been picked up. Folks on larger CPU systems with modules will want to just upgrade if vmalloc space has been an issue on bootup. Given the size of this request, here's some more elaborate details: The functional change change in this pull request is the very first patch from Song Liu which replaces the 'struct module_layout' with a new 'struct module_memory'. The old data structure tried to put together all types of supported module memory types in one data structure, the new one abstracts the differences in memory types in a module to allow each one to provide their own set of details. This paves the way in the future so we can deal with them in a cleaner way. If you look at changes they also provide a nice cleanup of how we handle these different memory areas in a module. This change has been in linux-next since before the merge window opened for v6.3 so to provide more than a full kernel cycle of testing. It's a good thing as quite a bit of fixes have been found for it. Jason Baron then made dynamic debug a first class citizen module user by using module notifier callbacks to allocate / remove module specific dynamic debug information. Nick Alcock has done quite a bit of work cross-tree to remove module license tags from things which cannot possibly be module at my request so to: a) help him with his longer term tooling goals which require a deterministic evaluation if a piece a symbol code could ever be part of a module or not. But quite recently it is has been made clear that tooling is not the only one that would benefit. Disambiguating symbols also helps efforts such as live patching, kprobes and BPF, but for other reasons and R&D on this area is active with no clear solution in sight. b) help us inch closer to the now generally accepted long term goal of automating all the MODULE_LICENSE() tags from SPDX license tags In so far as a) is concerned, although module license tags are a no-op for non-modules, tools which would want create a mapping of possible modules can only rely on the module license tag after the commit 8b41fc4454e ("kbuild: create modules.builtin without Makefile.modbuiltin or tristate.conf"). Nick has been working on this *for years* and AFAICT I was the only one to suggest two alternatives to this approach for tooling. The complexity in one of my suggested approaches lies in that we'd need a possible-obj-m and a could-be-module which would check if the object being built is part of any kconfig build which could ever lead to it being part of a module, and if so define a new define -DPOSSIBLE_MODULE [0]. A more obvious yet theoretical approach I've suggested would be to have a tristate in kconfig imply the same new -DPOSSIBLE_MODULE as well but that means getting kconfig symbol names mapping to modules always, and I don't think that's the case today. I am not aware of Nick or anyone exploring either of these options. Quite recently Josh Poimboeuf has pointed out that live patching, kprobes and BPF would benefit from resolving some part of the disambiguation as well but for other reasons. The function granularity KASLR (fgkaslr) patches were mentioned but Joe Lawrence has clarified this effort has been dropped with no clear solution in sight [1]. In the meantime removing module license tags from code which could never be modules is welcomed for both objectives mentioned above. Some developers have also welcomed these changes as it has helped clarify when a module was never possible and they forgot to clean this up, and so you'll see quite a bit of Nick's patches in other pull requests for this merge window. I just picked up the stragglers after rc3. LWN has good coverage on the motivation behind this work [2] and the typical cross-tree issues he ran into along the way. The only concrete blocker issue he ran into was that we should not remove the MODULE_LICENSE() tags from files which have no SPDX tags yet, even if they can never be modules. Nick ended up giving up on his efforts due to having to do this vetting and backlash he ran into from folks who really did *not understand* the core of the issue nor were providing any alternative / guidance. I've gone through his changes and dropped the patches which dropped the module license tags where an SPDX license tag was missing, it only consisted of 11 drivers. To see if a pull request deals with a file which lacks SPDX tags you can just use: ./scripts/spdxcheck.py -f \ $(git diff --name-only commid-id | xargs echo) You'll see a core module file in this pull request for the above, but that's not related to his changes. WE just need to add the SPDX license tag for the kernel/module/kmod.c file in the future but it demonstrates the effectiveness of the script. Most of Nick's changes were spread out through different trees, and I just picked up the slack after rc3 for the last kernel was out. Those changes have been in linux-next for over two weeks. The cleanups, debug code I added and final fix I added for modules were motivated by David Hildenbrand's report of boot failing on a systems with over 400 CPUs when KASAN was enabled due to running out of virtual memory space. Although the functional change only consists of 3 lines in the patch "module: avoid allocation if module is already present and ready", proving that this was the best we can do on the modules side took quite a bit of effort and new debug code. The initial cleanups I did on the modules side of things has been in linux-next since around rc3 of the last kernel, the actual final fix for and debug code however have only been in linux-next for about a week or so but I think it is worth getting that code in for this merge window as it does help fix / prove / evaluate the issues reported with larger number of CPUs. Userspace is not yet fixed as it is taking a bit of time for folks to understand the crux of the issue and find a proper resolution. Worst come to worst, I have a kludge-of-concept [3] of how to make kernel_read*() calls for modules unique / converge them, but I'm currently inclined to just see if userspace can fix this instead" Link: https://lore.kernel.org/all/Y/kXDqW+7d71C4wz@bombadil.infradead.org/ [0] Link: https://lkml.kernel.org/r/025f2151-ce7c-5630-9b90-98742c97ac65@redhat.com [1] Link: https://lwn.net/Articles/927569/ [2] Link: https://lkml.kernel.org/r/20230414052840.1994456-3-mcgrof@kernel.org [3] * tag 'modules-6.4-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux: (121 commits) module: add debugging auto-load duplicate module support module: stats: fix invalid_mod_bytes typo module: remove use of uninitialized variable len module: fix building stats for 32-bit targets module: stats: include uapi/linux/module.h module: avoid allocation if module is already present and ready module: add debug stats to help identify memory pressure module: extract patient module check into helper modules/kmod: replace implementation with a semaphore Change DEFINE_SEMAPHORE() to take a number argument module: fix kmemleak annotations for non init ELF sections module: Ignore L0 and rename is_arm_mapping_symbol() module: Move is_arm_mapping_symbol() to module_symbol.h module: Sync code of is_arm_mapping_symbol() scripts/gdb: use mem instead of core_layout to get the module address interconnect: remove module-related code interconnect: remove MODULE_LICENSE in non-modules zswap: remove MODULE_LICENSE in non-modules zpool: remove MODULE_LICENSE in non-modules x86/mm/dump_pagetables: remove MODULE_LICENSE in non-modules ...
2023-04-13nvmem: core: remove MODULE_LICENSE in non-modulesNick Alcock1-1/+0
Since commit 8b41fc4454e ("kbuild: create modules.builtin without Makefile.modbuiltin or tristate.conf"), MODULE_LICENSE declarations are used to identify modules. As a consequence, uses of the macro in non-modules will cause modprobe to misidentify their containing object file as a module when it is not (false positives), and modprobe might succeed rather than failing with a suitable error message. So remove it in the files in this commit, none of which can be built as modules. Signed-off-by: Nick Alcock <nick.alcock@oracle.com> Suggested-by: Luis Chamberlain <mcgrof@kernel.org> Cc: Luis Chamberlain <mcgrof@kernel.org> Cc: linux-modules@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: Hitomi Hasegawa <hasegawa-hitomi@fujitsu.com> Cc: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Signed-off-by: Luis Chamberlain <mcgrof@kernel.org>
2023-04-05nvmem: core: support specifying both: cell raw data & post read lengthsRafał Miłecki1-4/+7
Callback .read_post_process() is designed to modify raw cell content before providing it to the consumer. So far we were dealing with modifications that didn't affect cell size (length). In some cases however cell content needs to be reformatted and resized. It's required e.g. to provide properly formatted MAC address in case it's stored in a non-binary format (e.g. using ASCII). There were few discussions how to optimally handle that. Following possible solutions were considered: 1. Allow .read_post_process() to realloc (resize) content buffer 2. Allow .read_post_process() to adjust (decrease) just buffer length 3. Register NVMEM cells using post-read sizes The preferred solution was the last one. The problem is that simply adjusting "bytes" in NVMEM providers would result in core code NOT passing whole raw data to .read_post_process() callbacks. It means callback functions couldn't do their job without somehow manually reading original cell content on their own. This patch deals with that by registering NVMEM cells with both lengths: raw content one and post read one. It allows: 1. Core code to read whole raw cell content 2. Callbacks to return content they want Signed-off-by: Rafał Miłecki <rafal@milecki.pl> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230404172148.82422-35-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-05nvmem: core: provide own priv pointer in post process callbackMichael Walle1-1/+3
It doesn't make any more sense to have a opaque pointer set up by the nvmem device. Usually, the layout isn't associated with a particular nvmem device. Instead, let the caller who set the post process callback provide the priv pointer. Signed-off-by: Michael Walle <michael@walle.cc> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230404172148.82422-21-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-05nvmem: cell: drop global cell_post_processMichael Walle1-9/+0
There are no users anymore for the global cell_post_process callback anymore. New users should use proper nvmem layouts. Signed-off-by: Michael Walle <michael@walle.cc> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230404172148.82422-20-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-05nvmem: core: allow to modify a cell before adding itMichael Walle1-0/+4
Provide a way to modify a cell before it will get added. This is useful to attach a custom post processing hook via a layout. Signed-off-by: Michael Walle <michael@walle.cc> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230404172148.82422-18-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-05nvmem: core: add per-cell post processingMichael Walle1-0/+17
Instead of relying on the name the consumer is using for the cell, like it is done for the nvmem .cell_post_process configuration parameter, provide a per-cell post processing hook. This can then be populated by the NVMEM provider (or the NVMEM layout) when adding the cell. Signed-off-by: Michael Walle <michael@walle.cc> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230404172148.82422-17-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-05nvmem: core: request layout modules loadingMiquel Raynal1-0/+8
When a storage device like an eeprom or an mtd device probes, it registers an nvmem device if the nvmem subsystem has been enabled (bool symbol). During nvmem registration, if the device is using layouts to expose dynamic nvmem cells, the core will first try to get a reference over the layout driver callbacks. In practice there is not relationship that can be described between the storage driver and the nvmem layout. So there is no way we can enforce both drivers will be built-in or both will be modules. If the storage device driver is built-in but the layout is built as a module, instead of badly failing with an endless probe deferral loop, lets just make a modprobe call in case the driver was made available in an initramfs with of_device_node_request_module(), and offer a fully functional system to the user. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Tested-by: Michael Walle <michael@walle.cc> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230404172148.82422-16-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-05nvmem: core: handle the absence of expected layoutsMiquel Raynal1-1/+9
Make nvmem_layout_get() return -EPROBE_DEFER while the expected layout is not available. This condition cannot be triggered today as nvmem layout drivers are initialed as part of an early init call, but soon these drivers will be converted into modules and be initialized with a standard priority, so the unavailability of the drivers might become a reality that must be taken care of. Let's anticipate this by telling the caller the layout might not yet be available. A probe deferral is requested in this case. Please note this does not affect any nvmem device not using layouts, because an early check against the "nvmem-layout" container presence will return NULL in this case. Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Tested-by: Michael Walle <michael@walle.cc> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230404172148.82422-15-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-05nvmem: core: introduce NVMEM layoutsMichael Walle1-0/+120
NVMEM layouts are used to generate NVMEM cells during runtime. Think of an EEPROM with a well-defined conent. For now, the content can be described by a device tree or a board file. But this only works if the offsets and lengths are static and don't change. One could also argue that putting the layout of the EEPROM in the device tree is the wrong place. Instead, the device tree should just have a specific compatible string. Right now there are two use cases: (1) The NVMEM cell needs special processing. E.g. if it only specifies a base MAC address offset and you need to add an offset, or it needs to parse a MAC from ASCII format or some proprietary format. (Post processing of cells is added in a later commit). (2) u-boot environment parsing. The cells don't have a particular offset but it needs parsing the content to determine the offsets and length. Co-developed-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Miquel Raynal <miquel.raynal@bootlin.com> Signed-off-by: Michael Walle <michael@walle.cc> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230404172148.82422-14-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-10nvmem: core: return -ENOENT if nvmem cell is not foundMichael Walle1-1/+1
Prior to commit 5d8e6e6c10a3 ("nvmem: core: add an index parameter to the cell") of_nvmem_cell_get() would return -ENOENT if the cell wasn't found. Particularly, if of_property_match_string() returned -EINVAL, that return code was passed as the index to of_parse_phandle(), which then detected it as invalid and returned NULL. That led to an return code of -ENOENT. With the new code, the negative index will lead to an -EINVAL of of_parse_phandle_with_optional_args() which pass straight to the caller and break those who expect an -ENOENT. Fix it by always returning -ENOENT. Fixes: 5d8e6e6c10a3 ("nvmem: core: add an index parameter to the cell") Reported-by: Alexander Stein <alexander.stein@ew.tq-group.com> Link: https://lore.kernel.org/r/2143916.GUh0CODmnK@steina-w/ Signed-off-by: Michael Walle <michael@walle.cc> Tested-by: Alexander Stein <alexander.stein@ew.tq-group.com> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230310094845.139400-1-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-06nvmem: core: use nvmem_add_one_cell() in nvmem_add_cells_from_of()Michael Walle1-31/+14
Convert nvmem_add_cells_from_of() to use the new nvmem_add_one_cell(). This will remove duplicate code and it will make it possible to add a hook to a nvmem layout in between, which can change fields before the cell is finally added. Signed-off-by: Michael Walle <michael@walle.cc> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230206134356.839737-17-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-06nvmem: core: add nvmem_add_one_cell()Michael Walle1-24/+35
Add a new function to add exactly one cell. This will be used by the nvmem layout drivers to add custom cells. In contrast to the nvmem_add_cells(), this has the advantage that we don't have to assemble a list of cells on runtime. Signed-off-by: Michael Walle <michael@walle.cc> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230206134356.839737-16-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-06nvmem: core: drop the removal of the cells in nvmem_add_cells()Michael Walle1-10/+4
If nvmem_add_cells() fails, the whole nvmem_register() will fail and the cells will then be removed anyway. This is a preparation to introduce a nvmem_add_one_cell() which can then be used by nvmem_add_cells(). This is then the same to what nvmem_add_cells_from_table() and nvmem_add_cells_from_of() do. Signed-off-by: Michael Walle <michael@walle.cc> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230206134356.839737-15-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-06nvmem: core: add an index parameter to the cellMichael Walle1-11/+26
Sometimes a cell can represend multiple values. For example, a base ethernet address stored in the NVMEM can be expanded into multiple discreet ones by adding an offset. For this use case, introduce an index parameter which is then used to distiguish between values. This parameter will then be passed to the post process hook which can then use it to create different values during reading. At the moment, there is only support for the device tree path. You can add the index to the phandle, e.g. &net { nvmem-cells = <&base_mac_address 2>; nvmem-cell-names = "mac-address"; }; &nvmem_provider { base_mac_address: base-mac-address@0 { #nvmem-cell-cells = <1>; reg = <0 6>; }; }; Signed-off-by: Michael Walle <michael@walle.cc> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230206134356.839737-13-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-06nvmem: core: remove spurious white spaceRussell King (Oracle)1-1/+1
Remove a spurious white space in for the ida_alloc() call. Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230206134356.839737-8-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-28nvmem: core: fix return valueRussell King (Oracle)1-0/+1
Dan Carpenter points out that the return code was not set in commit 60c8b4aebd8e ("nvmem: core: fix cleanup after dev_set_name()"), but this is not the only issue - we also need to zero wp_gpio to prevent gpiod_put() being called on an error value. Fixes: 560181d3ace6 ("nvmem: core: fix cleanup after dev_set_name()") Cc: stable@vger.kernel.org Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230127104015.23839-10-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-28nvmem: core: fix cell removal on errorMichael Walle1-2/+1
nvmem_add_cells() could return an error after some cells are already added to the provider. In this case, the added cells are not removed. Remove any registered cells if nvmem_add_cells() fails. Fixes: fa72d847d68d7 ("nvmem: check the return value of nvmem_add_cells()") Cc: stable@vger.kernel.org Signed-off-by: Michael Walle <michael@walle.cc> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230127104015.23839-9-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-28nvmem: core: fix device node refcountingMichael Walle1-3/+8
In of_nvmem_cell_get(), of_get_next_parent() is used on cell_np. This will decrement the refcount on cell_np, but cell_np is still used later in the code. Use of_get_parent() instead and of_node_put() in the appropriate places. Fixes: 69aba7948cbe ("nvmem: Add a simple NVMEM framework for consumers") Fixes: 7ae6478b304b ("nvmem: core: rework nvmem cell instance creation") Cc: stable@vger.kernel.org Signed-off-by: Michael Walle <michael@walle.cc> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230127104015.23839-8-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-28nvmem: core: fix registration vs use raceRussell King (Oracle)1-10/+8
The i.MX6 CPU frequency driver sometimes fails to register at boot time due to nvmem_cell_read_u32() sporadically returning -ENOENT. This happens because there is a window where __nvmem_device_get() in of_nvmem_cell_get() is able to return the nvmem device, but as cells have been setup, nvmem_find_cell_entry_by_node() returns NULL. The occurs because the nvmem core registration code violates one of the fundamental principles of kernel programming: do not publish data structures before their setup is complete. Fix this by making nvmem core code conform with this principle. Fixes: eace75cfdcf7 ("nvmem: Add a simple NVMEM framework for nvmem providers") Cc: stable@vger.kernel.org Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230127104015.23839-7-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-28nvmem: core: fix cleanup after dev_set_name()Russell King (Oracle)1-12/+10
If dev_set_name() fails, we leak nvmem->wp_gpio as the cleanup does not put this. While a minimal fix for this would be to add the gpiod_put() call, we can do better if we split device_register(), and use the tested nvmem_release() cleanup code by initialising the device early, and putting the device. This results in a slightly larger fix, but results in clear code. Note: this patch depends on "nvmem: core: initialise nvmem->id early" and "nvmem: core: remove nvmem_config wp_gpio". Fixes: 5544e90c8126 ("nvmem: core: add error handling for dev_set_name") Cc: stable@vger.kernel.org Reported-by: kernel test robot <lkp@intel.com> Reported-by: Dan Carpenter <error27@gmail.com> Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> [Srini: Fixed subject line and error code handing with wp_gpio while applying.] Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230127104015.23839-6-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-28nvmem: core: remove nvmem_config wp_gpioRussell King (Oracle)1-3/+1
No one provides wp_gpio, so let's remove it to avoid issues with the nvmem core putting this gpio. Cc: stable@vger.kernel.org Signed-off-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk> Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@linaro.org> Link: https://lore.kernel.org/r/20230127104015.23839-5-srinivas.kandagatla@linaro.org Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>