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-rw-r--r--drivers/i2c/i2c-core.h90
1 files changed, 90 insertions, 0 deletions
diff --git a/drivers/i2c/i2c-core.h b/drivers/i2c/i2c-core.h
new file mode 100644
index 000000000..ec28024a6
--- /dev/null
+++ b/drivers/i2c/i2c-core.h
@@ -0,0 +1,90 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * i2c-core.h - interfaces internal to the I2C framework
+ */
+
+#include <linux/kconfig.h>
+#include <linux/rwsem.h>
+
+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;
+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);
+
+/*
+ * 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!
+ */
+static inline bool i2c_in_atomic_xfer_mode(void)
+{
+ return system_state > SYSTEM_RUNNING &&
+ (IS_ENABLED(CONFIG_PREEMPT_COUNT) ? !preemptible() : irqs_disabled());
+}
+
+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);
+#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)
+{
+ 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;