kernel/linux.git/include/linux/i2c.h, branch v6.6.131

i2c: core: Lock address during client device instantiation

2024-10-10T09:58:01+00:00

[ Upstream commit 8d3cefaf659265aa82b0373a563fdb9d16a2b947 ] Krzysztof reported an issue [0] which is caused by parallel attempts to instantiate the same I2C client device. This can happen if driver supports auto-detection, but certain devices are also instantiated explicitly. The original change isn't actually wrong, it just revealed that I2C core isn't prepared yet to handle this scenario. Calls to i2c_new_client_device() can be nested, therefore we can't use a simple mutex here. Parallel instantiation of devices at different addresses is ok, so we just have to prevent parallel instantiation at the same address. We can use a bitmap with one bit per 7-bit I2C client address, and atomic bit operations to set/check/clear bits. Now a parallel attempt to instantiate a device at the same address will result in -EBUSY being returned, avoiding the "sysfs: cannot create duplicate filename" splash. Note: This patch version includes small cosmetic changes to the Tested-by version, only functional change is that address locking is supported for slave addresses too. [0] https://lore.kernel.org/linux-i2c/9479fe4e-eb0c-407e-84c0-bd60c15baf74@ans.pl/T/#m12706546e8e2414d8f1a0dc61c53393f731685cc Fixes: caba40ec3531 ("eeprom: at24: Probe for DDR3 thermal sensor in the SPD case") Cc: stable@vger.kernel.org Tested-by: Krzysztof Piotr Oledzki Signed-off-by: Heiner Kallweit Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin

i2c: create debugfs entry per adapter

2024-10-10T09:58:01+00:00

[ Upstream commit 73febd775bdbdb98c81255ff85773ac410ded5c4 ] Two drivers already implement custom debugfs handling for their i2c_adapter and more will come. So, let the core create a debugfs directory per adapter and pass that to drivers for their debugfs files. Signed-off-by: Wolfram Sang Signed-off-by: Wolfram Sang Stable-dep-of: 8d3cefaf6592 ("i2c: core: Lock address during client device instantiation") Signed-off-by: Sasha Levin

i2c: Use IS_REACHABLE() for substituting empty ACPI functions

2024-09-08T05:54:49+00:00

commit 71833e79a42178d8a50b5081c98c78ace9325628 upstream. Replace IS_ENABLED() with IS_REACHABLE() to substitute empty stubs for: i2c_acpi_get_i2c_resource() i2c_acpi_client_count() i2c_acpi_find_bus_speed() i2c_acpi_new_device_by_fwnode() i2c_adapter *i2c_acpi_find_adapter_by_handle() i2c_acpi_waive_d0_probe() commit f17c06c6608a ("i2c: Fix conditional for substituting empty ACPI functions") partially fixed this conditional to depend on CONFIG_I2C, but used IS_ENABLED(), which is wrong since CONFIG_I2C is tristate. CONFIG_ACPI is boolean but let's also change it to use IS_REACHABLE() to future-proof it against becoming tristate. Somehow despite testing various combinations of CONFIG_I2C and CONFIG_ACPI we missed the combination CONFIG_I2C=m, CONFIG_ACPI=y. Signed-off-by: Richard Fitzgerald Fixes: f17c06c6608a ("i2c: Fix conditional for substituting empty ACPI functions") Reported-by: kernel test robot Closes: https://lore.kernel.org/oe-kbuild-all/202408141333.gYnaitcV-lkp@intel.com/ Reviewed-by: Takashi Iwai Signed-off-by: Wolfram Sang Signed-off-by: Greg Kroah-Hartman

i2c: Fix conditional for substituting empty ACPI functions

2024-09-08T05:54:31+00:00

[ Upstream commit f17c06c6608ad4ecd2ccf321753fb511812d821b ] Add IS_ENABLED(CONFIG_I2C) to the conditional around a bunch of ACPI functions. The conditional around these functions depended only on CONFIG_ACPI. But the functions are implemented in I2C core, so are only present if CONFIG_I2C is enabled. Signed-off-by: Richard Fitzgerald Signed-off-by: Wolfram Sang Signed-off-by: Sasha Levin

i2c: Drop legacy callback .probe_new()

2023-09-13T08:48:48+00:00

Now that all drivers are converted to the (new) .probe() callback, the temporary .probe_new() can go away. \o/ Link: https://lore.kernel.org/linux-i2c/20230626094548.559542-1-u.kleine-koenig@pengutronix.de Reviewed-by: Javier Martinez Canillas Reviewed-by: Jean Delvare Signed-off-by: Uwe Kleine-König Signed-off-by: Wolfram Sang

i2c: Add i2c_get_match_data()

2023-06-09T15:30:47+00:00

Add i2c_get_match_data() to get match data for I2C, ACPI and DT-based matching, so that we can optimize the driver code. Suggested-by: Geert Uytterhoeven Signed-off-by: Biju Das [wsa: simplified var initialization] Signed-off-by: Wolfram Sang

i2c: gxp: fix build failure without CONFIG_I2C_SLAVE

2023-05-03T15:27:29+00:00

The gxp_i2c_slave_irq_handler() is hidden in an #ifdef, but the caller uses an IS_ENABLED() check: drivers/i2c/busses/i2c-gxp.c: In function 'gxp_i2c_irq_handler': drivers/i2c/busses/i2c-gxp.c:467:29: error: implicit declaration of function 'gxp_i2c_slave_irq_handler'; did you mean 'gxp_i2c_irq_handler'? [-Werror=implicit-function-declaration] It has to consistently use one method or the other to avoid warnings, so move to IS_ENABLED() here for readability and build coverage, and move the #ifdef in linux/i2c.h to allow building it as dead code. Fixes: 4a55ed6f89f5 ("i2c: Add GXP SoC I2C Controller") Signed-off-by: Arnd Bergmann Reviewed-by: Nick Hawkins Signed-off-by: Wolfram Sang

i2c: Switch .probe() to not take an id parameter

2023-03-09T20:59:11+00:00

Commit b8a1a4cd5a98 ("i2c: Provide a temporary .probe_new() call-back type") introduced a new probe callback to convert i2c init routines to not take an i2c_device_id parameter. Now that all in-tree drivers are converted to the temporary .probe_new() callback, .probe() can be modified to match the desired prototype. Now that .probe() and .probe_new() have the same semantic, they can be defined as members of an anonymous union to save some memory and simplify the core code a bit. Signed-off-by: Uwe Kleine-König Signed-off-by: Wolfram Sang

i2c: add fwnode APIs

2023-01-17T08:29:59+00:00

Add fwnode APIs for finding and getting I2C adapters, which will be used by the SFP code. These are passed the fwnode corresponding to the adapter, and return the I2C adapter. It is the responsibility of the caller to find the appropriate fwnode. We keep the DT and ACPI interfaces, but where appropriate, recode them to use the fwnode interfaces internally. Reviewed-by: Mika Westerberg Signed-off-by: Russell King (Oracle) Signed-off-by: Wolfram Sang

i2c: core: Introduce i2c_client_get_device_id helper function

2022-11-14T19:49:33+00:00

Introduces new helper function to aid in .probe_new() refactors. In order to use existing i2c_get_device_id() on the probe callback, the device match table needs to be accessible in that function, which would require bigger refactors in some drivers using the deprecated .probe callback. This issue was discussed in more detail in the IIO mailing list. Link: https://lore.kernel.org/all/20221023132302.911644-11-u.kleine-koenig@pengutronix.de/ Suggested-by: Nuno Sá Suggested-by: Andy Shevchenko Suggested-by: Jonathan Cameron Signed-off-by: Angel Iglesias Reviewed-by: Andy Shevchenko Reviewed-by: Jonathan Cameron Signed-off-by: Wolfram Sang