diff options
Diffstat (limited to 'drivers/i2c/i2c-core-smbus.c')
| -rw-r--r-- | drivers/i2c/i2c-core-smbus.c | 55 |
1 files changed, 55 insertions, 0 deletions
diff --git a/drivers/i2c/i2c-core-smbus.c b/drivers/i2c/i2c-core-smbus.c index 10f00a82ec9d..4bb9927afd01 100644 --- a/drivers/i2c/i2c-core-smbus.c +++ b/drivers/i2c/i2c-core-smbus.c @@ -17,6 +17,7 @@ #include <linux/device.h> #include <linux/err.h> #include <linux/i2c.h> +#include <linux/i2c-smbus.h> #define CREATE_TRACE_POINTS #include <trace/events/smbus.h> @@ -592,3 +593,57 @@ s32 i2c_smbus_read_i2c_block_data_or_emulated(const struct i2c_client *client, return i; } EXPORT_SYMBOL(i2c_smbus_read_i2c_block_data_or_emulated); + +/** + * i2c_setup_smbus_alert - Setup SMBus alert support + * @adapter: the target adapter + * @setup: setup data for the SMBus alert handler + * Context: can sleep + * + * Setup handling of the SMBus alert protocol on a given I2C bus segment. + * + * Handling can be done either through our IRQ handler, or by the + * adapter (from its handler, periodic polling, or whatever). + * + * NOTE that if we manage the IRQ, we *MUST* know if it's level or + * edge triggered in order to hand it to the workqueue correctly. + * If triggering the alert seems to wedge the system, you probably + * should have said it's level triggered. + * + * This returns the ara client, which should be saved for later use with + * i2c_handle_smbus_alert() and ultimately i2c_unregister_device(); or NULL + * to indicate an error. + */ +struct i2c_client *i2c_setup_smbus_alert(struct i2c_adapter *adapter, + struct i2c_smbus_alert_setup *setup) +{ + struct i2c_board_info ara_board_info = { + I2C_BOARD_INFO("smbus_alert", 0x0c), + .platform_data = setup, + }; + + return i2c_new_device(adapter, &ara_board_info); +} +EXPORT_SYMBOL_GPL(i2c_setup_smbus_alert); + +#if IS_ENABLED(CONFIG_I2C_SMBUS) && IS_ENABLED(CONFIG_OF) +int of_i2c_setup_smbus_alert(struct i2c_adapter *adapter) +{ + struct i2c_client *client; + int irq; + + irq = of_property_match_string(adapter->dev.of_node, "interrupt-names", + "smbus_alert"); + if (irq == -EINVAL || irq == -ENODATA) + return 0; + else if (irq < 0) + return irq; + + client = i2c_setup_smbus_alert(adapter, NULL); + if (!client) + return -ENODEV; + + return 0; +} +EXPORT_SYMBOL_GPL(of_i2c_setup_smbus_alert); +#endif |