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* i2c: smbus: Send alert notifications to all devices if source not foundGuenter Roeck2024-08-041-3/+35
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a SMBus alert is received and the originating device is not found, the reason may be that the address reported on the SMBus alert address is corrupted, for example because multiple devices asserted alert and do not correctly implement SMBus arbitration. If this happens, call alert handlers on all devices connected to the given I2C bus, in the hope that this cleans up the situation. This change reliably fixed the problem on a system with multiple devices on a single bus. Example log where the device on address 0x18 (ADM1021) and on address 0x4c (ADT7461A) both had the alert line asserted: smbus_alert 3-000c: SMBALERT# from dev 0x0c, flag 0 smbus_alert 3-000c: no driver alert()! smbus_alert 3-000c: SMBALERT# from dev 0x0c, flag 0 smbus_alert 3-000c: no driver alert()! lm90 3-0018: temp1 out of range, please check! lm90 3-0018: Disabling ALERT# lm90 3-0029: Everything OK lm90 3-002a: Everything OK lm90 3-004c: temp1 out of range, please check! lm90 3-004c: temp2 out of range, please check! lm90 3-004c: Disabling ALERT# Fixes: b5527a7766f0 ("i2c: Add SMBus alert support") Signed-off-by: Guenter Roeck <linux@roeck-us.net> [wsa: fixed a typo in the commit message] Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
* i2c: smbus: Improve handling of stuck alertsGuenter Roeck2024-07-291-7/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The following messages were observed while testing alert functionality on systems with multiple I2C devices on a single bus if alert was active on more than one chip. smbus_alert 3-000c: SMBALERT# from dev 0x0c, flag 0 smbus_alert 3-000c: no driver alert()! and: smbus_alert 3-000c: SMBALERT# from dev 0x28, flag 0 Once it starts, this message repeats forever at high rate. There is no device at any of the reported addresses. Analysis shows that this is seen if multiple devices have the alert pin active. Apparently some devices do not support SMBus arbitration correctly. They keep sending address bits after detecting an address collision and handle the collision not at all or too late. Specifically, address 0x0c is seen with ADT7461A at address 0x4c and ADM1021 at address 0x18 if alert is active on both chips. Address 0x28 is seen with ADT7483 at address 0x2a and ADT7461 at address 0x4c if alert is active on both chips. Once the system is in bad state (alert is set by more than one chip), it often only recovers by power cycling. To reduce the impact of this problem, abort the endless loop in smbus_alert() if the same address is read more than once and not handled by a driver. Fixes: b5527a7766f0 ("i2c: Add SMBus alert support") Signed-off-by: Guenter Roeck <linux@roeck-us.net> [wsa: it also fixed an interrupt storm in one of my experiments] Tested-by: Wolfram Sang <wsa+renesas@sang-engineering.com> [wsa: rebased, moved a comment as well, improved the 'invalid' value] Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
* i2c: smbus: remove i801 assumptions from SPD probingThomas Weißschuh2024-07-201-11/+4
| | | | | | | | | | | | | | | The check and warning are very specific to the SPD usage of the i801 driver. That was fine as long as i801 was the only caller of i2c_register_spd(). Now that piix4 will be added as another user of that function, the check and warning are not accurate anymore. Instead of introducing a more complicated calling protocol only to print a warning, drop the warning. Even in cases where not all slots can be probed, then at least probe the 8 slots that can be. Signed-off-by: Thomas Weißschuh <linux@weissschuh.net> Reviewed-by: Heiner Kallweit <hkallweit1@gmail.com> Signed-off-by: Andi Shyti <andi.shyti@kernel.org>
* Merge tag 'i2c-for-6.11-rc1-try2' of ↵Linus Torvalds2024-07-191-1/+1
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux Pull i2c fixes from Wolfram Sang: "The I2C core gains documentation updates for the testunit, a cleanup regarding unneeded 'driver_data' and more sanity checks in the char device. For the host drivers, this release includes significant updates, with the primary change being the renaming from "master/slave" to "controller/target" to adhere to I2C v7 and SMBus 3.2 standards. New Support: - Added support for Intel Arrow Lake-H - Added I2C support in the Arioha SoC by linking the Mediatek I2C controller Cleanups: - Added the MODULE_DESCRIPTION() macro, resolving a modpost warning in the ALi 1563 Southbridge driver. - Constified the regmap_config declaration in the i2c-designware driver. - Improved the coding style in the Renesas R-Car driver by removing unnecessary semicolons after brackets. General improvements: - In the OMAP device, replaced NOIRQ_SYSTEM_SLEEP_PM_OPS with RUNTIME_PM_OPS to enable waking up the controller during suspend() before suspend_noirq() kicks in. - Improved logging in the Xilinx driver. - Added a warning (WARN()) in the Renesas R-Car driver for spurious interrupts. DTS Changes: - Removed address-cell and size-cell from the Atmel at91sam, nVidia Tegra 20, and Samsung S3c2410 devices. - Fixed Texas Instruments OMAP4 I2C controller to comply with the i2c-controller.yaml schema. - Improved indentation in DTS examples for several I2C devices. - Converted the NXP LPC1788 binding to the dt-schema. - Added documentation for the compatible string thead,th1520-i2c. - Added the "power-domains" property for the Meson I2C driver. AT24 EEPROM driver changes: - add support for two new Microchip models - document even more new models in DT bindings (those use fallback compatibles so no code changes)" * tag 'i2c-for-6.11-rc1-try2' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: (87 commits) i2c: document new callbacks in i2c_algorithm dt-bindings: i2c: amlogic,meson6-i2c: add optional power-domains dt-bindings: i2c: at91: Add sama7d65 compatible string i2c: st: reword according to newest specification i2c: cpm: reword according to newest specification i2c: virtio: reword according to newest specification i2c: nvidia-gpu: reword according to newest specification i2c: viai2c: reword according to newest specification i2c: viperboard: reword according to newest specification i2c: uniphier: reword according to newest specification i2c: uniphier-f: reword according to newest specification i2c: tiny-usb: reword according to newest specification i2c: thunderx-pcidrv: reword according to newest specification i2c: tegra-bpmp: reword according to newest specification i2c: taos-evm: reword according to newest specification i2c: sun6i-p2wi: reword according to newest specification i2c: stm32f4: reword according to newest specification i2c: sprd: reword according to newest specification i2c: sis5595: reword according to newest specification i2c: rzv2m: reword according to newest specification ...
| * i2c: Drop explicit initialization of struct i2c_device_id::driver_data to 0Uwe Kleine-König2024-06-261-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | These drivers don't use the driver_data member of struct i2c_device_id, so don't explicitly initialize this member. This prepares putting driver_data in an anonymous union which requires either no initialization or named designators. But it's also a nice cleanup on its own. While add it, also remove a comma after the sentinel entry. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@baylibre.com> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
* | i2c: smbus: Support DDR5 and LPDDR5 SPD EEPROMsGuenter Roeck2024-06-101-1/+5
|/ | | | | | | | | | | Detect (LP)DDR5 memory and instantiate the SPD5118 driver automatically. Suggested-by: Thomas Weißschuh <linux@weissschuh.net> Cc: Wolfram Sang <wsa+renesas@sang-engineering.com> Acked-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Reviewed-by: Armin Wolf <W_Armin@gmx.de> Reviewed-by: Thomas Weißschuh <linux@weissschuh.net> Signed-off-by: Guenter Roeck <linux@roeck-us.net>
* i2c: smbus: Prepare i2c_register_spd for usage on muxed segmentsHeiner Kallweit2024-03-041-7/+12
| | | | | | | | | | | | | | | If this is an adapter on a muxed bus segment, assume that each segment is connected to a subset of the (> 8) overall memory slots. In this case let's probe the maximum of 8 slots, however stop if the number of overall populated slots is reached. If we're not on a muxed segment and the total number of slots is > 8, then warn because then not all SPD eeproms can be addressed. Presumably the bus is muxed, but the mux config is missing. Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com> [wsa: removed a superfluous printout] Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
* i2c: smbus: Support up to 8 SPD EEPROMsJean Delvare2024-01-181-4/+4
| | | | | | | | | | | | | | | | | I originally restricted i2c_register_spd() to only support systems with up to 4 memory slots, so that we can experiment with it on a limited numbers of systems. It's been more than 3 years and it seems to work just fine, so the time has come to lift this arbitrary limitation. The maximum number of memory slots which can be connected to a single I2C segment is 8, so support that many SPD EEPROMs. Any system with more than 8 memory slots would have either multiple SMBus channels or SMBus multiplexing, so it would need dedicated care. We'll get to that later as needed. Signed-off-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Wolfram Sang <wsa@kernel.org>
* i2c: Convert drivers to new .probe() callbackUwe Kleine-König2023-03-091-1/+1
| | | | | | | | | | Now that .probe() was changed not to get the id parameter, drivers can be converted back to that with the eventual goal to drop .probe_new(). Implement that for the i2c drivers that are part of the i2c core. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Wolfram Sang <wsa@kernel.org>
* drivers/i2c: use simple i2c probeStephen Kitt2022-12-051-3/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | All these drivers have an i2c probe function which doesn't use the "struct i2c_device_id *id" parameter, so they can trivially be converted to the "probe_new" style of probe with a single argument. This is part of an ongoing transition to single-argument i2c probe functions. Old-style probe functions involve a call to i2c_match_id: in drivers/i2c/i2c-core-base.c, /* * When there are no more users of probe(), * rename probe_new to probe. */ if (driver->probe_new) status = driver->probe_new(client); else if (driver->probe) status = driver->probe(client, i2c_match_id(driver->id_table, client)); else status = -EINVAL; Drivers which don't need the second parameter can be declared using probe_new instead, avoiding the call to i2c_match_id. Drivers which do can still be converted to probe_new-style, calling i2c_match_id themselves (as is done currently for of_match_id). This change was done using the following Coccinelle script, and fixed up for whitespace changes: @ rule1 @ identifier fn; identifier client, id; @@ - static int fn(struct i2c_client *client, const struct i2c_device_id *id) + static int fn(struct i2c_client *client) { ...when != id } @ rule2 depends on rule1 @ identifier rule1.fn; identifier driver; @@ struct i2c_driver driver = { - .probe + .probe_new = ( fn | - &fn + fn ) , }; Signed-off-by: Stephen Kitt <steve@sk2.org> Signed-off-by: Wolfram Sang <wsa@kernel.org>
* i2c: smbus: add DDR support for SPDCorentin Labbe2022-12-011-0/+6
| | | | | | | | | | | | | | | | | | On my x05 laptop I got: Memory type 0x12 not supported yet, not instantiating SPD Adding the 0x12 case lead to a successful instantiated SPD AT24 EEPROM. i801_smbus 0000:00:1f.3: SMBus using polling i2c i2c-6: 2/2 memory slots populated (from DMI) at24 6-0050: 256 byte spd EEPROM, read-only i2c i2c-6: Successfully instantiated SPD at 0x50 at24 6-0051: 256 byte spd EEPROM, read-only And then, I decoded it successfully via decode-dimms. Signed-off-by: Corentin Labbe <clabbe@baylibre.com> Reviewed-by: Jean Delvare <jdelvare@suse.de> Signed-off-by: Wolfram Sang <wsa@kernel.org>
* i2c: Make remove callback return voidUwe Kleine-König2022-08-161-2/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The value returned by an i2c driver's remove function is mostly ignored. (Only an error message is printed if the value is non-zero that the error is ignored.) So change the prototype of the remove function to return no value. This way driver authors are not tempted to assume that passing an error to the upper layer is a good idea. All drivers are adapted accordingly. There is no intended change of behaviour, all callbacks were prepared to return 0 before. Reviewed-by: Peter Senna Tschudin <peter.senna@gmail.com> Reviewed-by: Jeremy Kerr <jk@codeconstruct.com.au> Reviewed-by: Benjamin Mugnier <benjamin.mugnier@foss.st.com> Reviewed-by: Javier Martinez Canillas <javierm@redhat.com> Reviewed-by: Crt Mori <cmo@melexis.com> Reviewed-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Acked-by: Marek Behún <kabel@kernel.org> # for leds-turris-omnia Acked-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Petr Machata <petrm@nvidia.com> # for mlxsw Reviewed-by: Maximilian Luz <luzmaximilian@gmail.com> # for surface3_power Acked-by: Srinivas Pandruvada <srinivas.pandruvada@linux.intel.com> # for bmc150-accel-i2c + kxcjk-1013 Reviewed-by: Hans Verkuil <hverkuil-cisco@xs4all.nl> # for media/* + staging/media/* Acked-by: Miguel Ojeda <ojeda@kernel.org> # for auxdisplay/ht16k33 + auxdisplay/lcd2s Reviewed-by: Luca Ceresoli <luca.ceresoli@bootlin.com> # for versaclock5 Reviewed-by: Ajay Gupta <ajayg@nvidia.com> # for ucsi_ccg Acked-by: Jonathan Cameron <Jonathan.Cameron@huawei.com> # for iio Acked-by: Peter Rosin <peda@axentia.se> # for i2c-mux-*, max9860 Acked-by: Adrien Grassein <adrien.grassein@gmail.com> # for lontium-lt8912b Reviewed-by: Jean Delvare <jdelvare@suse.de> # for hwmon, i2c-core and i2c/muxes Acked-by: Corey Minyard <cminyard@mvista.com> # for IPMI Reviewed-by: Vladimir Oltean <olteanv@gmail.com> Acked-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Acked-by: Sebastian Reichel <sebastian.reichel@collabora.com> # for drivers/power Acked-by: Krzysztof Hałasa <khalasa@piap.pl> Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Wolfram Sang <wsa@kernel.org>
* i2c: move core from strlcpy to strscpyWolfram Sang2022-08-111-1/+1
| | | | | | | | | | Follow the advice of the below link and prefer 'strscpy'. Conversion is easy because no code used the return value. It has been done with a simple sed invocation. Link: https://lore.kernel.org/r/CAHk-=wgfRnXz0W3D37d01q3JFkr_i_uTL=V6A6G1oUZcprmknw@mail.gmail.com/ Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
* i2c: smbus: Use device_*() functions instead of of_*()Akhil R2022-01-281-2/+3
| | | | | | | | | | 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 <akhilrajeev@nvidia.com> Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
* i2c: smbus: add core function handling SMBus host-notifyAlain Volmat2020-09-091-0/+107
| | | | | | | | | | | | | | | | | | | | | 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 <alain.volmat@st.com> Reviewed-by: Pierre-Yves MORDRET <pierre-yves.mordret@st.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
* i2c: smbus: Add a way to instantiate SPD EEPROMs automaticallyJean Delvare2020-05-291-1/+103
| | | | | | | | | | | 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 <jdelvare@suse.de> [wsa: minor change for new API] Signed-off-by: Wolfram Sang <wsa@kernel.org>
* i2c: convert SMBus alert setup function to return an ERRPTRWolfram Sang2020-03-101-1/+1
| | | | | | | | | | | | 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 <wsa+renesas@sang-engineering.com> Reviewed-by: Luca Ceresoli <luca@lucaceresoli.net> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: smbus: Don't filter out duplicate alertsCorey Minyard2019-11-251-7/+0
| | | | | | | | | | | | | | Getting the same alert twice in a row is legal and normal, especially on a fast device (like running in qemu). Kind of like interrupts. So don't report duplicate alerts, and deliver them normally. [JD: Fixed subject] Signed-off-by: Corey Minyard <cminyard@mvista.com> Signed-off-by: Jean Delvare <jdelvare@suse.de> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157Thomas Gleixner2019-05-301-10/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Based on 3 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 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 [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] 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 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 [author] [graeme] [gregory] [gg]@[slimlogic] [co] [uk] [author] [kishon] [vijay] [abraham] [i] [kishon]@[ti] [com] [based] [on] [twl6030]_[usb] [c] [author] [hema] [hk] [hemahk]@[ti] [com] 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 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-or-later has been chosen to replace the boilerplate/reference in 1105 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Allison Randal <allison@lohutok.net> Reviewed-by: Richard Fontana <rfontana@redhat.com> Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190527070033.202006027@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* i2c: i2c-smbus: add of_i2c_setup_smbus_alertPhil Reid2017-10-281-1/+9
| | | | | | | | | 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 <preid@electromag.com.au> Acked-by: Rob Herring <robh@kernel.org> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: i2c-smbus: Move i2c_setup_smbus_alert from i2c-smbus to i2c-core-smbusPhil Reid2017-10-281-32/+0
| | | | | | | | | In preparation to adding of_i2c_setup_smbus_alert() move i2c_setup_smbus_alert() to core module. of_i2c_setup_smbus_alert() will call i2c_setup_smbus_alert() and this avoid module dependecy issues. Signed-off-by: Phil Reid <preid@electromag.com.au> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: i2c-smbus: Use threaded irq for smbalertPhil Reid2017-10-281-24/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 <preid@electromag.com.au> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: use an IRQ to report Host Notify events, not alertBenjamin Tissoires2016-11-241-102/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The current SMBus Host Notify implementation relies on .alert() to relay its notifications. However, the use cases where SMBus Host Notify is needed currently is to signal data ready on touchpads. This is closer to an IRQ than a custom API through .alert(). Given that the 2 touchpad manufacturers (Synaptics and Elan) that use SMBus Host Notify don't put any data in the SMBus payload, the concept actually matches one to one. Benefits are multiple: - simpler code and API: the client will just have an IRQ, and nothing needs to be added in the adapter beside internally enabling it. - no more specific workqueue, the threading is handled by IRQ core directly (when required) - no more races when removing the device (the drivers are already required to disable irq on remove) - simpler handling for drivers: use plain regular IRQs - no more dependency on i2c-smbus for i2c-i801 (and any other adapter) - the IRQ domain is created automatically when the adapter exports the Host Notify capability - the IRQ are assign only if ACPI, OF and the caller did not assign one already - the domain is automatically destroyed on remove - fewer lines of code (minus 20, yeah!) Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: i2c-smbus: fix i2c_handle_smbus_host_notify documentationJean Delvare2016-07-181-2/+2
| | | | | | | | | The parameter description is from a previous implementation, update it to describe the actual implementation. Signed-off-by: Jean Delvare <jdelvare@suse.de> Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: smbus: add SMBus Host Notify supportBenjamin Tissoires2016-06-171-5/+108
| | | | | | | | | | | | | | | | | | SMBus Host Notify allows a slave device to act as a master on a bus to notify the host of an interrupt. On Intel chipsets, the functionality is directly implemented in the firmware. We just need to export a function to call .alert() on the proper device driver. i2c_handle_smbus_host_notify() behaves like i2c_handle_smbus_alert(). When called, it schedules a task that will be able to sleep to go through the list of devices attached to the adapter. The current implementation allows one Host Notification to be scheduled while an other is running. Tested-by: Andrew Duggan <aduggan@synaptics.com> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: add a protocol parameter to the alert callbackBenjamin Tissoires2016-06-171-1/+2
| | | | | | | | | | | | | | | | | | .alert() is meant to be generic, but there is currently no way for the device driver to know which protocol generated the alert. Add a parameter in .alert() to help the device driver to understand what is given in data. This patch is required to have the support of SMBus Host Notify protocol through .alert(). Tested-by: Andrew Duggan <aduggan@synaptics.com> For hwmon: Acked-by: Guenter Roeck <linux@roeck-us.net> For IPMI: Acked-by: Corey Minyard <cminyard@mvista.com> Signed-off-by: Benjamin Tissoires <benjamin.tissoires@redhat.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: i2c-smbus: sort includesWolfram Sang2016-02-201-4/+4
| | | | | | | I request this for drivers, so the core should adhere to sorted includes as well. Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: smbus: fix typo in commetShailendra Verma2015-06-011-1/+1
| | | | | Signed-off-by: Shailendra Verma <shailendra.capricorn@gmail.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: remove FSF addressWolfram Sang2014-11-071-5/+0
| | | | | | | We have a central copy of the GPL for that. Some addresses were already outdated. Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
* Update Jean Delvare's e-mail addressJean Delvare2014-01-291-2/+2
| | | | Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c: Remove redundant 'driver' field from the i2c_client structLars-Peter Clausen2013-10-031-4/+6
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The 'driver' field of the i2c_client struct is redundant. The same data can be accessed through to_i2c_driver(client->dev.driver). The generated code for both approaches in more or less the same. E.g. on ARM the expression client->driver->command(...) generates ... ldr r3, [r0, #28] ldr r3, [r3, #32] blx r3 ... and the expression to_i2c_driver(client->dev.driver)->command(...) generates ... ldr r3, [r0, #160] ldr r3, [r3, #-4] blx r3 ... Other architectures will generate similar code. All users of the 'driver' field outside of the I2C core have already been converted. So this only leaves the core itself. This patch converts the remaining few users in the I2C core and then removes the 'driver' field from the i2c_client struct. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c: use dev_get_platdata()Jingoo Han2013-08-191-1/+1
| | | | | | | | Use the wrapper function for retrieving the platform data instead of accessing dev->platform_data directly. Signed-off-by: Jingoo Han <jg1.han@samsung.com> Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
* i2c-smbus: Convert kzalloc to devm_kzallocJulia Lawall2012-10-051-7/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Converting kzalloc to devm_kzalloc simplifies the code and ensures that the result, alert, is freed after the irq allocated by the subsequent devm_request_irq. This in turn ensures that when an interrupt can be triggered, the alert structure is still available. The problem of a free after a devm_request_irq was found using the following semantic match (http://coccinelle.lip6.fr/) // <smpl> @r exists@ expression e1,e2,x,a,b,c,d; identifier free; position p1,p2; @@ devm_request_irq@p1(e1,e2,...,x) ... when any when != e2 = a when != x = b if (...) { ... when != e2 = c when != x = d free@p2(...,x,...); ... return ...; } // </smpl> Signed-off-by: Julia Lawall <Julia.Lawall@lip6.fr> Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c-smbus: Use module_i2c_driver()Fabio Estevam2012-07-241-12/+1
| | | | | | | Using module_i2c_driver() makes the code smaller and cleaner. Signed-off-by: Fabio Estevam <fabio.estevam@freescale.com> Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c: Update the FSF addressJean Delvare2012-03-261-1/+2
| | | | Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c: Remove all i2c_set_clientdata(client, NULL) in driversWolfram Sang2010-06-031-1/+0
| | | | | | | | | | | | | | | | | | | | | I2C drivers can use the clientdata-pointer to point to private data. As I2C devices are not really unregistered, but merely detached from their driver, it used to be the drivers obligation to clear this pointer during remove() or a failed probe(). As a couple of drivers forgot to do this, it was agreed that it was cleaner if the i2c-core does this clearance when appropriate, as there is no guarantee for the lifetime of the clientdata-pointer after remove() anyhow. This feature was added to the core with commit e4a7b9b04de15f6b63da5ccdd373ffa3057a3681 to fix the faulty drivers. As there is no need anymore to clear the clientdata-pointer, remove all current occurrences in the drivers to simplify the code and prevent confusion. Signed-off-by: Wolfram Sang <w.sang@pengutronix.de> Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com> Acked-by: Greg Kroah-Hartman <gregkh@suse.de> Acked-by: Richard Purdie <rpurdie@linux.intel.com> Acked-by: Dmitry Torokhov <dtor@mail.ru> Signed-off-by: Jean Delvare <khali@linux-fr.org>
* include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo2010-03-301-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
* i2c-smbus: Use device_lock/device_unlockStephen Rothwell2010-03-131-3/+2
| | | | | | | Use the new device locking/unlocking API. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Signed-off-by: Jean Delvare <khali@linux-fr.org>
* i2c: Add SMBus alert supportJean Delvare2010-03-021-0/+263
SMBus alert support. The SMBus alert protocol allows several SMBus slave devices to share a single interrupt pin on the SMBus master, while still allowing the master to know which slave triggered the interrupt. This is based on preliminary work by David Brownell. The key difference between David's implementation and mine is that his was part of i2c-core, while mine is split into a separate, standalone module named i2c-smbus. The i2c-smbus module is meant to include support for all SMBus extensions to the I2C protocol in the future. The benefit of this approach is a zero cost for I2C bus segments which do not need SMBus alert support. Where David's implementation increased the size of struct i2c_adapter by 7% (40 bytes on i386), mine doesn't touch it. Where David's implementation added over 150 lines of code to i2c-core (+10%), mine doesn't touch it. The only change that touches all the users of the i2c subsystem is a new callback in struct i2c_driver (common to both implementations.) I seem to remember Trent was worried about the footprint of David'd implementation, hopefully mine addresses the issue. Signed-off-by: Jean Delvare <khali@linux-fr.org> Acked-by: Jonathan Cameron <jic23@cam.ac.uk> Cc: David Brownell <dbrownell@users.sourceforge.net> Cc: Trent Piepho <tpiepho@freescale.com>