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author | Jean Delvare <khali@linux-fr.org> | 2010-04-01 15:55:46 -0700 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-04-01 15:55:46 -0700 |
commit | d8d6782349be3b550ebe438794c327b7373ce54e (patch) | |
tree | d7f9702669f2173cff860cf9e628dc6ca57b5888 | |
parent | 8859bd1aef1f4030afe5aac41b685e13f31c60fb (diff) | |
download | lwn-d8d6782349be3b550ebe438794c327b7373ce54e.tar.gz lwn-d8d6782349be3b550ebe438794c327b7373ce54e.zip |
i2c-tiny-usb: Fix on big-endian systems
commit 1c010ff8912cbc08d80e865aab9c32b6b00c527d upstream.
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
Acked-by: Jean Delvare <jdelvare@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r-- | drivers/i2c/busses/i2c-tiny-usb.c | 12 |
1 files changed, 6 insertions, 6 deletions
diff --git a/drivers/i2c/busses/i2c-tiny-usb.c b/drivers/i2c/busses/i2c-tiny-usb.c index b1c050ff311d..e29b6d5ba8ef 100644 --- a/drivers/i2c/busses/i2c-tiny-usb.c +++ b/drivers/i2c/busses/i2c-tiny-usb.c @@ -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; |