linux/drivers/i2c/i2c-core.h

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treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 157 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>
2019-05-27 06:55:06 +00:00
/* SPDX-License-Identifier: GPL-2.0-or-later */
i2c: Add i2c_board_info and i2c_new_device() This provides partial support for new-style I2C driver binding. It builds on "struct i2c_board_info" declarations that identify I2C devices on a given board. This is needed on systems with I2C devices that can't be fully probed and/or autoconfigured, such as many embedded Linux configurations where the way a given I2C device is wired may affect how it must be used. There are two models for declaring such devices: * LATE -- using a public function i2c_new_device(). This lets modules declare I2C devices found *AFTER* a given I2C adapter becomes available. For example, a PCI card could create adapters giving access to utility chips on that card, and this would be used to associate those chips with those adapters. * EARLY -- from arch_initcall() level code, using a non-exported function i2c_register_board_info(). This copies the declarations *BEFORE* such an i2c_adapter becomes available, arranging that i2c_new_device() will be called later when i2c-core registers the relevant i2c_adapter. For example, arch/.../.../board-*.c files would declare the I2C devices along with their platform data, and I2C devices would behave much like PNPACPI devices. (That is, both enumerate from board-specific tables.) To match the exported i2c_new_device(), the previously-private function i2c_unregister_device() is now exported. Pending later patches using these new APIs, this is effectively a NOP. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-05-01 21:26:31 +00:00
/*
* i2c-core.h - interfaces internal to the I2C framework
*/
#include <linux/kconfig.h>
#include <linux/rwsem.h>
i2c: Add i2c_board_info and i2c_new_device() This provides partial support for new-style I2C driver binding. It builds on "struct i2c_board_info" declarations that identify I2C devices on a given board. This is needed on systems with I2C devices that can't be fully probed and/or autoconfigured, such as many embedded Linux configurations where the way a given I2C device is wired may affect how it must be used. There are two models for declaring such devices: * LATE -- using a public function i2c_new_device(). This lets modules declare I2C devices found *AFTER* a given I2C adapter becomes available. For example, a PCI card could create adapters giving access to utility chips on that card, and this would be used to associate those chips with those adapters. * EARLY -- from arch_initcall() level code, using a non-exported function i2c_register_board_info(). This copies the declarations *BEFORE* such an i2c_adapter becomes available, arranging that i2c_new_device() will be called later when i2c-core registers the relevant i2c_adapter. For example, arch/.../.../board-*.c files would declare the I2C devices along with their platform data, and I2C devices would behave much like PNPACPI devices. (That is, both enumerate from board-specific tables.) To match the exported i2c_new_device(), the previously-private function i2c_unregister_device() is now exported. Pending later patches using these new APIs, this is effectively a NOP. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-05-01 21:26:31 +00:00
struct i2c_devinfo {
struct list_head list;
int busnum;
struct i2c_board_info board_info;
};
/* board_lock protects board_list and first_dynamic_bus_num.
* only i2c core components are allowed to use these symbols.
*/
extern struct rw_semaphore __i2c_board_lock;
i2c: Add i2c_board_info and i2c_new_device() This provides partial support for new-style I2C driver binding. It builds on "struct i2c_board_info" declarations that identify I2C devices on a given board. This is needed on systems with I2C devices that can't be fully probed and/or autoconfigured, such as many embedded Linux configurations where the way a given I2C device is wired may affect how it must be used. There are two models for declaring such devices: * LATE -- using a public function i2c_new_device(). This lets modules declare I2C devices found *AFTER* a given I2C adapter becomes available. For example, a PCI card could create adapters giving access to utility chips on that card, and this would be used to associate those chips with those adapters. * EARLY -- from arch_initcall() level code, using a non-exported function i2c_register_board_info(). This copies the declarations *BEFORE* such an i2c_adapter becomes available, arranging that i2c_new_device() will be called later when i2c-core registers the relevant i2c_adapter. For example, arch/.../.../board-*.c files would declare the I2C devices along with their platform data, and I2C devices would behave much like PNPACPI devices. (That is, both enumerate from board-specific tables.) To match the exported i2c_new_device(), the previously-private function i2c_unregister_device() is now exported. Pending later patches using these new APIs, this is effectively a NOP. Signed-off-by: David Brownell <dbrownell@users.sourceforge.net> Signed-off-by: Jean Delvare <khali@linux-fr.org>
2007-05-01 21:26:31 +00:00
extern struct list_head __i2c_board_list;
extern int __i2c_first_dynamic_bus_num;
int i2c_check_7bit_addr_validity_strict(unsigned short addr);
int i2c_dev_irq_from_resources(const struct resource *resources,
unsigned int num_resources);
2019-04-03 12:40:08 +00:00
/*
* We only allow atomic transfers for very late communication, e.g. to access a
* PMIC when powering down. Atomic transfers are a corner case and not for
* generic use!
2019-04-03 12:40:08 +00:00
*/
static inline bool i2c_in_atomic_xfer_mode(void)
{
return system_state > SYSTEM_RUNNING &&
(IS_ENABLED(CONFIG_PREEMPT_COUNT) ? !preemptible() : irqs_disabled());
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}
static inline int __i2c_lock_bus_helper(struct i2c_adapter *adap)
{
int ret = 0;
if (i2c_in_atomic_xfer_mode()) {
WARN(!adap->algo->master_xfer_atomic && !adap->algo->smbus_xfer_atomic,
"No atomic I2C transfer handler for '%s'\n", dev_name(&adap->dev));
ret = i2c_trylock_bus(adap, I2C_LOCK_SEGMENT) ? 0 : -EAGAIN;
} else {
i2c_lock_bus(adap, I2C_LOCK_SEGMENT);
}
return ret;
}
static inline int __i2c_check_suspended(struct i2c_adapter *adap)
{
if (test_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags)) {
if (!test_and_set_bit(I2C_ALF_SUSPEND_REPORTED, &adap->locked_flags))
dev_WARN(&adap->dev, "Transfer while suspended\n");
return -ESHUTDOWN;
}
return 0;
}
#ifdef CONFIG_ACPI
void i2c_acpi_register_devices(struct i2c_adapter *adap);
int i2c_acpi_get_irq(struct i2c_client *client, bool *wake_capable);
#else /* CONFIG_ACPI */
static inline void i2c_acpi_register_devices(struct i2c_adapter *adap) { }
static inline int i2c_acpi_get_irq(struct i2c_client *client, bool *wake_capable)
{
return 0;
}
#endif /* CONFIG_ACPI */
extern struct notifier_block i2c_acpi_notifier;
#ifdef CONFIG_ACPI_I2C_OPREGION
int i2c_acpi_install_space_handler(struct i2c_adapter *adapter);
void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter);
#else /* CONFIG_ACPI_I2C_OPREGION */
static inline int i2c_acpi_install_space_handler(struct i2c_adapter *adapter) { return 0; }
static inline void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter) { }
#endif /* CONFIG_ACPI_I2C_OPREGION */
#ifdef CONFIG_OF
void of_i2c_register_devices(struct i2c_adapter *adap);
#else
static inline void of_i2c_register_devices(struct i2c_adapter *adap) { }
#endif
extern struct notifier_block i2c_of_notifier;
#if IS_ENABLED(CONFIG_I2C_SMBUS)
int i2c_setup_smbus_alert(struct i2c_adapter *adap);
#else
static inline int i2c_setup_smbus_alert(struct i2c_adapter *adap)
{
return 0;
}
#endif