i2c: core: apply 'is_suspended' check for SMBus, too

We checked I2C calls, but not SMBus. Refactor the helper to an inline
function and use it for both, I2C and SMBus.

Fixes: 9ac6cb5f ("i2c: add suspended flag and accessors for i2c adapters")
Reported-by: NPeter Rosin <peda@axentia.se>
Signed-off-by: NWolfram Sang <wsa+renesas@sang-engineering.com>
Reviewed-by: NSimon Horman <horms+renesas@verge.net.au>
Signed-off-by: NWolfram Sang <wsa@the-dreams.de>

drivers/i2c/i2c-core-base.c

@@ -1867,11 +1867,10 @@ int __i2c_transfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
 
 	if (WARN_ON(!msgs || num < 1))
 		return -EINVAL;
-	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;
-	}
+
+	ret = __i2c_check_suspended(adap);
+	if (ret)
+		return ret;
 
 	if (adap->quirks && i2c_check_for_quirks(adap, msgs, num))
 		return -EOPNOTSUPP;

drivers/i2c/i2c-core-smbus.c

@@ -555,6 +555,10 @@ s32 __i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
 	int try;
 	s32 res;
 
+	res = __i2c_check_suspended(adapter);
+	if (res)
+		return res;
+
 	/* If enabled, the following two tracepoints are conditional on
 	 * read_write and protocol.
 	 */

drivers/i2c/i2c-core.h

@@ -54,6 +54,17 @@ static inline int __i2c_lock_bus_helper(struct i2c_adapter *adap)
 	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
 const struct acpi_device_id *
 i2c_acpi_match_device(const struct acpi_device_id *matches,