i2c: tiny-usb: do not use stack as URB transfer_buffer
Patch fixes i2c-tiny-usb not to use stack as URB transfer_buffer. URB buffers
need to be DMA-able, which stack is not.
Patch is only compile tested.
Signed-off-by: Jussi Kivilinna <jussi.kivilinna@iki.fi>
Signed-off-by: Wolfram Sang <wsa@the-dreams.de>
diff --git a/drivers/i2c/busses/i2c-tiny-usb.c b/drivers/i2c/busses/i2c-tiny-usb.c
index 0510636..e7d3b75 100644
--- a/drivers/i2c/busses/i2c-tiny-usb.c
+++ b/drivers/i2c/busses/i2c-tiny-usb.c
@@ -54,12 +54,16 @@
static int usb_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num)
{
- unsigned char status;
+ unsigned char *pstatus;
struct i2c_msg *pmsg;
- int i;
+ int i, ret;
dev_dbg(&adapter->dev, "master xfer %d messages:\n", num);
+ pstatus = kmalloc(sizeof(*pstatus), GFP_KERNEL);
+ if (!pstatus)
+ return -ENOMEM;
+
for (i = 0 ; i < num ; i++) {
int cmd = CMD_I2C_IO;
@@ -84,7 +88,8 @@
pmsg->buf, pmsg->len) != pmsg->len) {
dev_err(&adapter->dev,
"failure reading data\n");
- return -EREMOTEIO;
+ ret = -EREMOTEIO;
+ goto out;
}
} else {
/* write data */
@@ -93,36 +98,50 @@
pmsg->buf, pmsg->len) != pmsg->len) {
dev_err(&adapter->dev,
"failure writing data\n");
- return -EREMOTEIO;
+ ret = -EREMOTEIO;
+ goto out;
}
}
/* read status */
- if (usb_read(adapter, CMD_GET_STATUS, 0, 0, &status, 1) != 1) {
+ if (usb_read(adapter, CMD_GET_STATUS, 0, 0, pstatus, 1) != 1) {
dev_err(&adapter->dev, "failure reading status\n");
- return -EREMOTEIO;
+ ret = -EREMOTEIO;
+ goto out;
}
- dev_dbg(&adapter->dev, " status = %d\n", status);
- if (status == STATUS_ADDRESS_NAK)
- return -EREMOTEIO;
+ dev_dbg(&adapter->dev, " status = %d\n", *pstatus);
+ if (*pstatus == STATUS_ADDRESS_NAK) {
+ ret = -EREMOTEIO;
+ goto out;
+ }
}
- return i;
+ ret = i;
+out:
+ kfree(pstatus);
+ return ret;
}
static u32 usb_func(struct i2c_adapter *adapter)
{
- __le32 func;
+ __le32 *pfunc;
+ u32 ret;
+
+ pfunc = kmalloc(sizeof(*pfunc), GFP_KERNEL);
/* get functionality from adapter */
- if (usb_read(adapter, CMD_GET_FUNC, 0, 0, &func, sizeof(func)) !=
- sizeof(func)) {
+ if (!pfunc || usb_read(adapter, CMD_GET_FUNC, 0, 0, pfunc,
+ sizeof(*pfunc)) != sizeof(*pfunc)) {
dev_err(&adapter->dev, "failure reading functionality\n");
- return 0;
+ ret = 0;
+ goto out;
}
- return le32_to_cpu(func);
+ ret = le32_to_cpup(pfunc);
+out:
+ kfree(pfunc);
+ return ret;
}
/* This is the actual algorithm we define */