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2025-05-23Merge tag 'i2c-host-6.16' of ↵Wolfram Sang
git://git.kernel.org/pub/scm/linux/kernel/git/andi.shyti/linux into i2c/for-mergewindow i2c-host updates for v6.16 Cleanups and refactorings - Many drivers switched to dev_err_probe() - Generic cleanups applied to designware, iproc, ismt, mlxbf, npcm7xx, qcom-geni, pasemi, and thunderx - davinci: declare I2C mangling support among I2C features - designware: clean up DTS handling - designware: fix PM runtime on driver unregister - imx: improve error logging during probe - lpc2k: improve checks in probe error path - xgene-slimpro: improve PCC shared memory handling - pasemi: improve error handling in reset, smbus clear, timeouts - tegra: validate buffer length during transfers - wmt: convert binding to YAML format Improvements and extended support: - microchip-core: add SMBus support - mlxbf: add support for repeated start in block transfers - mlxbf: improve timer configuration - npcm: attempt clock toggle recovery before failing init - octeon: add support for block mode operations - pasemi: add support for unjam device feature - riic: add support for bus recovery New device support: - MediaTek Dimensity 1200 (MT6893) - Sophgo SG2044 - Renesas RZ/V2N (R9A09G056) - Rockchip RK3528 - AMD ISP (new driver) Misc changes: - core: add support for Write Disable-aware SPD
2025-05-22i2c: atr: add passthrough flagCosmin Tanislav
Some I2C ATRs can have other I2C ATRs as children. The I2C messages of the child ATRs need to be forwarded as-is if the parent I2C ATR can only do static mapping. In the case of GMSL, the deserializer I2C ATR actually doesn't have I2C address remapping hardware capabilities, but it is able to select which GMSL link to talk to, allowing it to change the address of the serializer. The child ATRs need to have their alias pools defined in such a way to prevent overlapping addresses between them, but there's no way around this without orchestration between multiple ATR instances. To allow for this use-case, add a flag that allows unmapped addresses to be passed through, since they are already remapped by the child ATRs. There's no case where an address that has not been remapped by the child ATR will hit the parent ATR. Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com> Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Reviewed-by: Romain Gantois <romain.gantois@bootlin.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2025-05-22i2c: atr: add static flagCosmin Tanislav
Some I2C ATRs do not support dynamic remapping, only static mapping of direct children. Mappings will only be added or removed as a result of devices being added or removed from a child bus. The ATR pool will have to be big enough to accommodate all devices expected to be added to the child buses. Add a new flag that prevents old mappings to be replaced or new mappings to be created in the alias finding code paths. That mens adding a flags parameter to i2c_atr_new() and an i2c_atr_flags enum. Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com> Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Reviewed-by: Romain Gantois <romain.gantois@bootlin.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2025-05-22i2c: atr: allow replacing mappings in attach_addr()Cosmin Tanislav
It is possible for aliases to be exhausted while we are still attaching children. Allow replacing mapping on attach by calling i2c_atr_replace_mapping_by_addr() if i2c_atr_create_mapping_by_addr() fails. Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com> Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2025-05-22i2c: atr: deduplicate logic in attach_addr()Cosmin Tanislav
This is the same logic as in i2c_atr_create_mapping_by_addr(). Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com> Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Reviewed-by: Romain Gantois <romain.gantois@bootlin.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2025-05-22i2c: atr: do not create mapping in detach_addr()Cosmin Tanislav
It is useless to create a new mapping just to detach it immediately. Use the newly added i2c_atr_find_mapping_by_addr() function to avoid it, and exit without logging an error if not found. Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com> Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2025-05-22i2c: atr: split up i2c_atr_get_mapping_by_addr()Cosmin Tanislav
The i2c_atr_get_mapping_by_addr() function handles three separate usecases: finding an existing mapping, creating a new mapping, or replacing an existing mapping if a new mapping cannot be created because there aren't enough aliases available. Split up the function into three different functions handling its individual usecases to prepare for better usage of each one. Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com> Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2025-05-22i2c: atr: find_mapping() -> get_mapping()Cosmin Tanislav
A find operation implies that a null result is not an error. Use get naming to clarify things and to prepare for splitting up the logic inside this function. Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com> Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2025-05-22i2c: atr: Fix lockdep for nested ATRsTomi Valkeinen
When we have an ATR, and another ATR as a subdevice of the first ATR, we get lockdep warnings for the i2c_atr.lock and i2c_atr_chan.orig_addrs_lock. This is because lockdep uses a static key for the locks, and doesn't see the locks of the separate ATR instances as separate. Fix this by generating a dynamic lock key per lock instance. Signed-off-by: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com> Signed-off-by: Cosmin Tanislav <demonsingur@gmail.com> Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2025-05-02i2c: atr: Fix end of loop test in i2c_atr_find_mapping_by_addr()Dan Carpenter
When the list_for_each_entry_reverse() exits without hitting a break then the list cursor points to invalid memory. So this check for if (c2a->fixed) is checking bogus memory. Fix it by using a "found" variable to track if we found what we were looking for or not. The list head (i2c_atr_chan.alias_pairs) is not a full entry, it's just a struct list_head. When the for loop runs to completion, c2a doesn't point to a struct i2c_atr_alias_pair, so you can't access c2a->fixed. Fixes: c3f55241882b ("i2c: Support dynamic address translation") Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org> Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> Reviewed-by: Romain Gantois <romain.gantois@bootlin.com> Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2025-04-18i2c: Support dynamic address translationRomain Gantois
The i2c-atr module keeps a list of associations between I2C client aliases and I2C addresses. This represents the address translation table which is programmed into an ATR channel at any given time. This list is only updated when a new client is bound to the channel. However in some cases, an ATR channel can have more downstream clients than available aliases. One example of this is an SFP module that is bound to an FPC202 port. The FPC202 port can only access up to two logical I2C addresses. However, the SFP module may expose up to three logical I2C addresses: its EEPROM on 7-bit addresses 0x50 and 0x51, and a PHY transceiver on address 0x56. In cases like these, it is necessary to reconfigure the channel's translation table on the fly, so that all three I2C addresses can be accessed when needed. As there are currently no known ATR's which do not support dynamic address translation, this feature can be enabled by default without breaking existing use cases. Modify the i2c-atr module to provide on-the-fly address translation. This is achieved by modifying an ATR channel's translation table whenever an I2C transaction with unmapped clients is requested. Add a mutex to protect alias_list. This prevents i2c_atr_dynamic_attach/detach_addr from racing with the bus notifier handler to modify alias_list. Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> Signed-off-by: Romain Gantois <romain.gantois@bootlin.com> Acked-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2025-04-18i2c: support per-channel ATR alias poolsRomain Gantois
Some I2C address translators (ATRs) assign each of their remote peripheral aliases to a specific channel. To properly handle these devices, add support for having separate alias pools for each ATR channel. This is achieved by allowing callers of i2c_atr_add_adapter to pass an optional alias list. If present, this list will be used to populate the channel's alias pool. Otherwise, the common alias pool will be used. Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> Signed-off-by: Romain Gantois <romain.gantois@bootlin.com> Acked-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2025-04-18i2c: rename field 'alias_list' of struct i2c_atr_chan to 'alias_pairs'Romain Gantois
The "alias_list" field of struct i2c_atr_chan describes translation table entries programmed in the ATR channel. This terminology will become more confusing when per-channel alias pool support is introduced, as struct i2c_atr_chan will gain a new field called "alias_pool", which will describe aliases which are available to the ATR channel. Rename the "alias_list" field to "alias_pairs" to clearly distinguish it from the future "alias_pool" field. No functional change is intended. Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> Signed-off-by: Romain Gantois <romain.gantois@bootlin.com> Acked-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2025-04-18i2c: move ATR alias pool to a separate structRomain Gantois
Each I2C address translator (ATR) has a pool of client aliases which can be used as translation targets. Some ATRs have a single alias pool shared by all downstream channels, while others have a separate alias pool for each channel. Currently, this alias pool is represented by the "aliases", "num_aliases", and "use_mask" fields of struct i2c_atr. In preparation for adding per-channel alias pool support, move the "aliases", "num_aliases", "use_mask" and associated lock to a new struct called "struct alias_pool". Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> Signed-off-by: Romain Gantois <romain.gantois@bootlin.com> Acked-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2025-04-18i2c: use client addresses directly in ATR interfaceRomain Gantois
The I2C Address Translator (ATR) module defines mappings from i2c_client structs to aliases. However, only the physical address of each i2c_client struct is actually relevant to the workings of the ATR module. Moreover, some drivers require address translation functionality but do not allocate i2c_client structs, accessing the adapter directly instead. The SFP subsystem is an example of this. Replace the "i2c_client" field of the i2c_atr_alias_pair struct with a u16 "addr" field. Rewrite helper functions and callbacks as needed. Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> Tested-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> Signed-off-by: Romain Gantois <romain.gantois@bootlin.com> Acked-by: Andi Shyti <andi.shyti@kernel.org> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2025-04-16i2c: atr: Fix wrong includeAndy Shevchenko
The fwnode.h is not supposed to be used by the drivers as it has the definitions for the core parts for different device property provider implementations. Drop it. Note, that fwnode API for drivers is provided in property.h which is included here. Fixes: a076a860acae ("media: i2c: add I2C Address Translator (ATR) support") Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Mukesh Kumar Savaliya <quic_msavaliy@quicinc.com> Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Reviewed-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> [wsa: reworded subject] Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2025-01-09i2c: atr: Fix client detachTomi Valkeinen
i2c-atr catches the BUS_NOTIFY_DEL_DEVICE event on the bus and removes the translation by calling i2c_atr_detach_client(). However, BUS_NOTIFY_DEL_DEVICE happens when the device is about to be removed from this bus, i.e. before removal, and thus before calling .remove() on the driver. If the driver happens to do any i2c transactions in its remove(), they will fail. Fix this by catching BUS_NOTIFY_REMOVED_DEVICE instead, thus removing the translation only after the device is actually removed. Fixes: a076a860acae ("media: i2c: add I2C Address Translator (ATR) support") Cc: stable@vger.kernel.org Signed-off-by: Tomi Valkeinen <tomi.valkeinen+renesas@ideasonboard.com> Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> Reviewed-by: Romain Gantois <romain.gantois@bootlin.com> Tested-by: Romain Gantois <romain.gantois@bootlin.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
2024-12-02module: Convert symbol namespace to string literalPeter Zijlstra
Clean up the existing export namespace code along the same lines of commit 33def8498fdd ("treewide: Convert macro and uses of __section(foo) to __section("foo")") and for the same reason, it is not desired for the namespace argument to be a macro expansion itself. Scripted using git grep -l -e MODULE_IMPORT_NS -e EXPORT_SYMBOL_NS | while read file; do awk -i inplace ' /^#define EXPORT_SYMBOL_NS/ { gsub(/__stringify\(ns\)/, "ns"); print; next; } /^#define MODULE_IMPORT_NS/ { gsub(/__stringify\(ns\)/, "ns"); print; next; } /MODULE_IMPORT_NS/ { $0 = gensub(/MODULE_IMPORT_NS\(([^)]*)\)/, "MODULE_IMPORT_NS(\"\\1\")", "g"); } /EXPORT_SYMBOL_NS/ { if ($0 ~ /(EXPORT_SYMBOL_NS[^(]*)\(([^,]+),/) { if ($0 !~ /(EXPORT_SYMBOL_NS[^(]*)\(([^,]+), ([^)]+)\)/ && $0 !~ /(EXPORT_SYMBOL_NS[^(]*)\(\)/ && $0 !~ /^my/) { getline line; gsub(/[[:space:]]*\\$/, ""); gsub(/[[:space:]]/, "", line); $0 = $0 " " line; } $0 = gensub(/(EXPORT_SYMBOL_NS[^(]*)\(([^,]+), ([^)]+)\)/, "\\1(\\2, \"\\3\")", "g"); } } { print }' $file; done Requested-by: Masahiro Yamada <masahiroy@kernel.org> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Link: https://mail.google.com/mail/u/2/#inbox/FMfcgzQXKWgMmjdFwwdsfgxzKpVHWPlc Acked-by: Greg KH <gregkh@linuxfoundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2023-09-24i2c: Annotate struct i2c_atr with __counted_byKees Cook
Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct i2c_atr. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Signed-off-by: Wolfram Sang <wsa@kernel.org>
2023-07-14media: i2c: add I2C Address Translator (ATR) supportLuca Ceresoli
An ATR is a device that looks similar to an i2c-mux: it has an I2C slave "upstream" port and N master "downstream" ports, and forwards transactions from upstream to the appropriate downstream port. But it is different in that the forwarded transaction has a different slave address. The address used on the upstream bus is called the "alias" and is (potentially) different from the physical slave address of the downstream chip. Add a helper file (just like i2c-mux.c for a mux or switch) to allow implementing ATR features in a device driver. The helper takes care of adapter creation/destruction and translates addresses at each transaction. Signed-off-by: Luca Ceresoli <luca@lucaceresoli.net> Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ideasonboard.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Wolfram Sang <wsa@kernel.org> Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com> Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>