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Diffstat (limited to 'drivers/i2c/i2c-core-smbus.c')
-rw-r--r--drivers/i2c/i2c-core-smbus.c55
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