redonkable/remarkable-linux
redonkable/remarkable-linux
1
0
Fork 0
Code Releases Activity

i2c-tiny-usb: Fix on big-endian systems

Browse source 
The functionality bit vector is always returned as a little-endian
32-bit number by the device, so it must be byte-swapped to the host
endianness.

On the other hand, the delay value is handled by the USB stack, so no
byte swapping is needed on our side.

This fixes bug #15105:
http://bugzilla.kernel.org/show_bug.cgi?id=15105

Reported-by: Jens Richter <jens@richter-stutensee.de>
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Tested-by: Jens Richter <jens@richter-stutensee.de>
Cc: Till Harbaum <till@harbaum.org>
Cc: stable@kernel.org
This commit is contained in:
Jean Delvare 2010-02-05 17:48:13 +01:00
parent fc76be434d
commit 1c010ff891
1 changed files with 6 additions and 6 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

12
drivers/i2c/busses/i2c-tiny-usb.c
View file

@ -13,6 +13,7 @@
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/types.h>
/* include interfaces to usb layer */
#include <linux/usb.h>
@ -31,8 +32,8 @@
#define CMD_I2C_IO_END (1<<1)
/* i2c bit delay, default is 10us -> 100kHz */
static int delay = 10;
module_param(delay, int, 0);
static unsigned short delay = 10;
module_param(delay, ushort, 0);
MODULE_PARM_DESC(delay, "bit delay in microseconds, "
"e.g. 10 for 100kHz (default is 100kHz)");
@ -109,7 +110,7 @@ static int usb_xfer(struct i2c_adapter *adapter, struct i2c_msg *msgs, int num)
static u32 usb_func(struct i2c_adapter *adapter)
{
u32 func;
__le32 func;
/* get functionality from adapter */
if (usb_read(adapter, CMD_GET_FUNC, 0, 0, &func, sizeof(func)) !=
@ -118,7 +119,7 @@ static u32 usb_func(struct i2c_adapter *adapter)
return 0;
}
return func;
return le32_to_cpu(func);
}
/* This is the actual algorithm we define */
@ -216,8 +217,7 @@ static int i2c_tiny_usb_probe(struct usb_interface *interface,
"i2c-tiny-usb at bus %03d device %03d",
dev->usb_dev->bus->busnum, dev->usb_dev->devnum);
if (usb_write(&dev->adapter, CMD_SET_DELAY,
cpu_to_le16(delay), 0, NULL, 0) != 0) {
if (usb_write(&dev->adapter, CMD_SET_DELAY, delay, 0, NULL, 0) != 0) {
dev_err(&dev->adapter.dev,
"failure setting delay to %dus\n", delay);
retval = -EIO;