From: Jun Gao <jun.gao@xxxxxxxxxxxx>
This function is needed by i2c_get_dma_safe_msg_buf() potentially.
It is used to free DMA safe buffer when DMA operation fails.
Signed-off-by: Jun Gao <jun.gao@xxxxxxxxxxxx>
---
drivers/i2c/i2c-core-base.c | 14 ++++++++++++++
include/linux/i2c.h | 1 +
2 files changed, 15 insertions(+)
diff --git a/drivers/i2c/i2c-core-base.c b/drivers/i2c/i2c-core-base.c
index 31d16ad..2b518ea 100644
--- a/drivers/i2c/i2c-core-base.c
+++ b/drivers/i2c/i2c-core-base.c
@@ -2288,6 +2288,20 @@ void i2c_release_dma_safe_msg_buf(struct i2c_msg *msg, u8 *buf)
}
EXPORT_SYMBOL_GPL(i2c_release_dma_safe_msg_buf);
+/**
+ * i2c_free_dma_safe_msg_buf - free DMA safe buffer
+ * @msg: the message related to DMA safe buffer
+ * @buf: the buffer obtained from i2c_get_dma_safe_msg_buf(). May be NULL.
+ */
+void i2c_free_dma_safe_msg_buf(struct i2c_msg *msg, u8 *buf)
+{
+ if (!buf || buf == msg->buf)
+ return;
+
+ kfree(buf);
+}
+EXPORT_SYMBOL_GPL(i2c_free_dma_safe_msg_buf);
+
MODULE_AUTHOR("Simon G. Vogl <simon@xxxxxxxxxxxxxxxxx>");
MODULE_DESCRIPTION("I2C-Bus main module");
MODULE_LICENSE("GPL");
diff --git a/include/linux/i2c.h b/include/linux/i2c.h
index 254cd34..6d62f93 100644
--- a/include/linux/i2c.h
+++ b/include/linux/i2c.h
@@ -860,6 +860,7 @@ static inline u8 i2c_8bit_addr_from_msg(const struct i2c_msg *msg)
u8 *i2c_get_dma_safe_msg_buf(struct i2c_msg *msg, unsigned int threshold);
void i2c_release_dma_safe_msg_buf(struct i2c_msg *msg, u8 *buf);
+void i2c_free_dma_safe_msg_buf(struct i2c_msg *msg, u8 *buf);
int i2c_handle_smbus_host_notify(struct i2c_adapter *adap, unsigned short addr);
/**
--
1.8.1.1
