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Diffstat (limited to 'drivers/i2c/i2c-core-smbus.c')
-rw-r--r--drivers/i2c/i2c-core-smbus.c35
1 files changed, 25 insertions, 10 deletions
diff --git a/drivers/i2c/i2c-core-smbus.c b/drivers/i2c/i2c-core-smbus.c
index 132119112596..3ac426a8ab5a 100644
--- a/drivers/i2c/i2c-core-smbus.c
+++ b/drivers/i2c/i2c-core-smbus.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Linux I2C core SMBus and SMBus emulation code
*
@@ -8,11 +9,6 @@
* All SMBus-related things are written by Frodo Looijaard <frodol@dds.nl>
* SMBus 2.0 support by Mark Studebaker <mdsxyz123@yahoo.com> and
* Jean Delvare <jdelvare@suse.de>
- *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU General Public License as published by the Free
- * Software Foundation; either version 2 of the License, or (at your option)
- * any later version.
*/
#include <linux/device.h>
#include <linux/err.h>
@@ -20,6 +16,8 @@
#include <linux/i2c-smbus.h>
#include <linux/slab.h>
+#include "i2c-core.h"
+
#define CREATE_TRACE_POINTS
#include <trace/events/smbus.h>
@@ -530,7 +528,10 @@ s32 i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
{
s32 res;
- i2c_lock_bus(adapter, I2C_LOCK_SEGMENT);
+ res = __i2c_lock_bus_helper(adapter);
+ if (res)
+ return res;
+
res = __i2c_smbus_xfer(adapter, addr, flags, read_write,
command, protocol, data);
i2c_unlock_bus(adapter, I2C_LOCK_SEGMENT);
@@ -543,10 +544,17 @@ s32 __i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
unsigned short flags, char read_write,
u8 command, int protocol, union i2c_smbus_data *data)
{
+ int (*xfer_func)(struct i2c_adapter *adap, u16 addr,
+ unsigned short flags, char read_write,
+ u8 command, int size, union i2c_smbus_data *data);
unsigned long orig_jiffies;
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.
*/
@@ -557,13 +565,20 @@ s32 __i2c_smbus_xfer(struct i2c_adapter *adapter, u16 addr,
flags &= I2C_M_TEN | I2C_CLIENT_PEC | I2C_CLIENT_SCCB;
- if (adapter->algo->smbus_xfer) {
+ xfer_func = adapter->algo->smbus_xfer;
+ if (i2c_in_atomic_xfer_mode()) {
+ if (adapter->algo->smbus_xfer_atomic)
+ xfer_func = adapter->algo->smbus_xfer_atomic;
+ else if (adapter->algo->master_xfer_atomic)
+ xfer_func = NULL; /* fallback to I2C emulation */
+ }
+
+ if (xfer_func) {
/* Retry automatically on arbitration loss */
orig_jiffies = jiffies;
for (res = 0, try = 0; try <= adapter->retries; try++) {
- res = adapter->algo->smbus_xfer(adapter, addr, flags,
- read_write, command,
- protocol, data);
+ res = xfer_func(adapter, addr, flags, read_write,
+ command, protocol, data);
if (res != -EAGAIN)
break;
if (time_after(jiffies,