kernel/linux.git/include/linux/i2c-smbus.h, branch v6.19.11

i2c: smbus: introduce Write Disable-aware SPD instantiating functions

2025-05-19T20:23:57+00:00

Some SMBus controllers may restrict writes to addresses where SPD sensors may reside. This may lead to some SPD sensors not functioning correctly, and might need extra handling. Introduce new SPD-instantiating functions that are aware of this, and use them instead. Signed-off-by: Yo-Jung Lin (Leo) Reviewed-by: Guenter Roeck Link: https://lore.kernel.org/r/20250430-for-upstream-i801-spd5118-no-instantiate-v2-1-2f54d91ae2c7@canonical.com Signed-off-by: Andi Shyti

i2c: don't expose function which is only used internally

2022-02-15T08:58:57+00:00

i2c_setup_smbus_alert() is only needed within the I2C core, so no need to expose it to other modules. Signed-off-by: Wolfram Sang Reviewed-by: Niklas Söderlund Signed-off-by: Wolfram Sang

i2c: smbus: Use device_() functions instead of of_()

2022-01-28T20:56:34+00:00

Change of_*() functions to device_*() for firmware agnostic usage. This allows to have the smbus_alert interrupt without any changes in the controller drivers using the ACPI table. Signed-off-by: Akhil R Reviewed-by: Andy Shevchenko Signed-off-by: Wolfram Sang

i2c: smbus: add core function handling SMBus host-notify

2020-09-09T08:38:28+00:00

SMBus Host-Notify protocol, from the adapter point of view consist of receiving a message from a client, including the client address and some other data. It can be simply handled by creating a new slave device and registering a callback performing the parsing of the message received from the client. This commit introduces two new core functions * i2c_new_slave_host_notify_device * i2c_free_slave_host_notify_device that take care of registration of the new slave device and callback and will call i2c_handle_smbus_host_notify once a Host-Notify event is received. Signed-off-by: Alain Volmat Reviewed-by: Pierre-Yves MORDRET Signed-off-by: Wolfram Sang

i2c: smbus: Add a way to instantiate SPD EEPROMs automatically

2020-05-29T10:53:04+00:00

In simple cases we can instantiate SPD EEPROMs on the SMBus automatically. Start with just DDR2, DDR3 and DDR4 on x86 for now, and only for systems with no more than 4 memory slots. These limitations may be lifted later. Signed-off-by: Jean Delvare [wsa: minor change for new API] Signed-off-by: Wolfram Sang

i2c: smbus: remove outdated references to irq level triggers

2020-03-10T11:20:04+00:00

IRQ levels are now handled within the IRQ core. Remove the forgotten references from the documentation. Fixes: 9b9f2b8bc2ac ("i2c: i2c-smbus: Use threaded irq for smbalert") Signed-off-by: Wolfram Sang Reviewed-by: Luca Ceresoli Signed-off-by: Wolfram Sang

i2c: convert SMBus alert setup function to return an ERRPTR

2020-03-10T11:19:52+00:00

Only few drivers use this call, so drivers and I2C core are converted at once with this patch. By simply using i2c_new_client_device() instead of i2c_new_device(), we easily can return an ERRPTR for this function as well. To make out of tree users aware that something changed, the function is renamed to i2c_new_smbus_alert_device(). Signed-off-by: Wolfram Sang Reviewed-by: Luca Ceresoli Signed-off-by: Wolfram Sang

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 1

2019-05-21T09:28:39+00:00

Based on 2 normalized pattern(s): this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 51 franklin street fifth floor boston ma 02110 1301 usa this program is free software you can redistribute it and or modify it under the terms of the gnu general public license as published by the free software foundation either version 2 of the license or at your option [no]_[pad]_[ctrl] any later version this program is distributed in the hope that it will be useful but without any warranty without even the implied warranty of merchantability or fitness for a particular purpose see the gnu general public license for more details you should have received a copy of the gnu general public license along with this program if not write to the free software foundation inc 51 franklin street fifth floor boston ma 02110 1301 usa extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 176 file(s). Signed-off-by: Thomas Gleixner Reviewed-by: Jilayne Lovejoy Reviewed-by: Steve Winslow Reviewed-by: Allison Randal Reviewed-by: Kate Stewart Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190519154040.652910950@linutronix.de Signed-off-by: Greg Kroah-Hartman

i2c: i2c-smbus: add of_i2c_setup_smbus_alert

2017-10-28T21:42:47+00:00

This commit adds of_i2c_setup_smbus_alert which allows the smbalert driver to be attached to an i2c adapter via the device tree. Signed-off-by: Phil Reid Acked-by: Rob Herring Signed-off-by: Wolfram Sang

i2c: i2c-smbus: Use threaded irq for smbalert

2017-10-28T21:42:26+00:00

Prior to this commit the smbalert_irq was handling in the hard irq context. This change switch to using a thread irq which avoids the need for the work thread. Using threaded irq also removes the need for the edge_triggered flag as the enabling / disabling of the hard irq for level triggered interrupts will be handled by the irq core. Without this change have an irq connected to something like an i2c gpio resulted in a null ptr deferences. Specifically handle_nested_irq calls the threaded irq handler. There are currently 3 in tree drivers affected by this change. i2c-parport driver calls i2c_handle_smbus_alert in a hard irq context. This driver use edge trigger interrupts which skip the enable / disable calls. But it still need to handle the smbus transaction on a thread. So the work thread is kept for this driver. i2c-parport-light & i2c-thunderx-pcidrv provide the irq number in the setup which will result in the thread irq being used. i2c-parport-light is edge trigger so the enable / disable call was skipped as well. i2c-thunderx-pcidrv is getting the edge / level trigger setting from of data and was setting the flag as required. However the irq core should handle this automatically. Signed-off-by: Phil Reid Reviewed-by: Benjamin Tissoires Signed-off-by: Wolfram Sang