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df7b4d6f7d
Atomic transfers are not only about sending messages like the original wording suggested. Speak of 'accessing' now like in i2c.h. Reported-by: Michał Mirosław <mirq-linux@rere.qmqm.pl> Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com> Signed-off-by: Wolfram Sang <wsa@kernel.org>
98 lines
2.9 KiB
C
98 lines
2.9 KiB
C
/* SPDX-License-Identifier: GPL-2.0-or-later */
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/*
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* i2c-core.h - interfaces internal to the I2C framework
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*/
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#include <linux/rwsem.h>
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struct i2c_devinfo {
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struct list_head list;
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int busnum;
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struct i2c_board_info board_info;
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};
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/* board_lock protects board_list and first_dynamic_bus_num.
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* only i2c core components are allowed to use these symbols.
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*/
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extern struct rw_semaphore __i2c_board_lock;
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extern struct list_head __i2c_board_list;
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extern int __i2c_first_dynamic_bus_num;
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int i2c_check_7bit_addr_validity_strict(unsigned short addr);
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int i2c_dev_irq_from_resources(const struct resource *resources,
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unsigned int num_resources);
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/*
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* We only allow atomic transfers for very late communication, e.g. to access a
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* PMIC when powering down. Atomic transfers are a corner case and not for
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* generic use!
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*/
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static inline bool i2c_in_atomic_xfer_mode(void)
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{
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return system_state > SYSTEM_RUNNING && irqs_disabled();
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}
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static inline int __i2c_lock_bus_helper(struct i2c_adapter *adap)
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{
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int ret = 0;
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if (i2c_in_atomic_xfer_mode()) {
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WARN(!adap->algo->master_xfer_atomic && !adap->algo->smbus_xfer_atomic,
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"No atomic I2C transfer handler for '%s'\n", dev_name(&adap->dev));
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ret = i2c_trylock_bus(adap, I2C_LOCK_SEGMENT) ? 0 : -EAGAIN;
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} else {
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i2c_lock_bus(adap, I2C_LOCK_SEGMENT);
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}
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return ret;
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}
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static inline int __i2c_check_suspended(struct i2c_adapter *adap)
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{
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if (test_bit(I2C_ALF_IS_SUSPENDED, &adap->locked_flags)) {
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if (!test_and_set_bit(I2C_ALF_SUSPEND_REPORTED, &adap->locked_flags))
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dev_WARN(&adap->dev, "Transfer while suspended\n");
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return -ESHUTDOWN;
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}
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return 0;
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}
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#ifdef CONFIG_ACPI
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const struct acpi_device_id *
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i2c_acpi_match_device(const struct acpi_device_id *matches,
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struct i2c_client *client);
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void i2c_acpi_register_devices(struct i2c_adapter *adap);
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int i2c_acpi_get_irq(struct i2c_client *client);
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#else /* CONFIG_ACPI */
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static inline void i2c_acpi_register_devices(struct i2c_adapter *adap) { }
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static inline const struct acpi_device_id *
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i2c_acpi_match_device(const struct acpi_device_id *matches,
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struct i2c_client *client)
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{
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return NULL;
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}
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static inline int i2c_acpi_get_irq(struct i2c_client *client)
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{
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return 0;
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}
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#endif /* CONFIG_ACPI */
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extern struct notifier_block i2c_acpi_notifier;
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#ifdef CONFIG_ACPI_I2C_OPREGION
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int i2c_acpi_install_space_handler(struct i2c_adapter *adapter);
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void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter);
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#else /* CONFIG_ACPI_I2C_OPREGION */
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static inline int i2c_acpi_install_space_handler(struct i2c_adapter *adapter) { return 0; }
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static inline void i2c_acpi_remove_space_handler(struct i2c_adapter *adapter) { }
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#endif /* CONFIG_ACPI_I2C_OPREGION */
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#ifdef CONFIG_OF
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void of_i2c_register_devices(struct i2c_adapter *adap);
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#else
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static inline void of_i2c_register_devices(struct i2c_adapter *adap) { }
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#endif
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extern struct notifier_block i2c_of_notifier;
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