The driver should select what CRC algorithm is required
when performing a checksum on the firmware.
rt61pci & rt73usb require crc-itu-t
rt2800pci & rt2800usb require crc-ccitt
Legacy 2800pci/usb driver uses crc-itu-t + bit order reversion,
but that is just inefficient especially since the end result is
the same as a different algorithm which is also available as library. ;)
Signed-off-by: Ivo van Doorn <IvDoorn@xxxxxxxxx>
---
drivers/net/wireless/rt2x00/Kconfig | 1 +
drivers/net/wireless/rt2x00/rt2x00.h | 2 +
drivers/net/wireless/rt2x00/rt2x00dev.c | 8 ++---
drivers/net/wireless/rt2x00/rt2x00firmware.c | 41 ++++++++++++++++++++------
drivers/net/wireless/rt2x00/rt61pci.c | 3 +-
drivers/net/wireless/rt2x00/rt73usb.c | 3 +-
6 files changed, 42 insertions(+), 16 deletions(-)
diff --git a/drivers/net/wireless/rt2x00/Kconfig b/drivers/net/wireless/rt2x00/Kconfig
index da05b1f..28f3e5e 100644
--- a/drivers/net/wireless/rt2x00/Kconfig
+++ b/drivers/net/wireless/rt2x00/Kconfig
@@ -28,6 +28,7 @@ config RT2X00_LIB_USB
config RT2X00_LIB_FIRMWARE
boolean
depends on RT2X00_LIB
+ select CRC_CCITT
select CRC_ITU_T
select FW_LOADER
diff --git a/drivers/net/wireless/rt2x00/rt2x00.h b/drivers/net/wireless/rt2x00/rt2x00.h
index 14668f0..d5b9a3c 100644
--- a/drivers/net/wireless/rt2x00/rt2x00.h
+++ b/drivers/net/wireless/rt2x00/rt2x00.h
@@ -555,6 +555,8 @@ enum rt2x00_flags {
* Driver features
*/
DRIVER_REQUIRE_FIRMWARE,
+ DRIVER_REQUIRE_FIRMWARE_CRC_ITU_T,
+ DRIVER_REQUIRE_FIRMWARE_CCITT,
DRIVER_REQUIRE_BEACON_GUARD,
DRIVER_REQUIRE_ATIM_QUEUE,
diff --git a/drivers/net/wireless/rt2x00/rt2x00dev.c b/drivers/net/wireless/rt2x00/rt2x00dev.c
index 9c4ebb0..7089808 100644
--- a/drivers/net/wireless/rt2x00/rt2x00dev.c
+++ b/drivers/net/wireless/rt2x00/rt2x00dev.c
@@ -983,11 +983,9 @@ int rt2x00lib_start(struct rt2x00_dev *rt2x00dev)
* If this is the first interface which is added,
* we should load the firmware now.
*/
- if (test_bit(DRIVER_REQUIRE_FIRMWARE, &rt2x00dev->flags)) {
- retval = rt2x00lib_load_firmware(rt2x00dev);
- if (retval)
- return retval;
- }
+ retval = rt2x00lib_load_firmware(rt2x00dev);
+ if (retval)
+ return retval;
/*
* Initialize the device.
diff --git a/drivers/net/wireless/rt2x00/rt2x00firmware.c b/drivers/net/wireless/rt2x00/rt2x00firmware.c
index 442ff80..4f9fe56 100644
--- a/drivers/net/wireless/rt2x00/rt2x00firmware.c
+++ b/drivers/net/wireless/rt2x00/rt2x00firmware.c
@@ -23,6 +23,7 @@
Abstract: rt2x00 firmware loading routines.
*/
+#include <linux/crc-ccitt.h>
#include <linux/crc-itu-t.h>
#include <linux/kernel.h>
#include <linux/module.h>
@@ -37,7 +38,6 @@ static int rt2x00lib_request_firmware(struct rt2x00_dev *rt2x00dev)
char *fw_name;
int retval;
u16 crc;
- u16 tmp;
/*
* Read correct firmware from harddisk.
@@ -64,17 +64,37 @@ static int rt2x00lib_request_firmware(struct rt2x00_dev *rt2x00dev)
}
/*
- * Validate the firmware using 16 bit CRC.
- * The last 2 bytes of the firmware are the CRC
- * so substract those 2 bytes from the CRC checksum,
- * and set those 2 bytes to 0 when calculating CRC.
+ * Perform crc validation on the firmware.
+ * The last 2 bytes in the firmware array are the crc checksum itself,
+ * this means that we should never pass those 2 bytes to the crc
+ * algorithm.
*/
- tmp = 0;
- crc = crc_itu_t(0, fw->data, fw->size - 2);
- crc = crc_itu_t(crc, (u8 *)&tmp, 2);
+ if (test_bit(DRIVER_REQUIRE_FIRMWARE_CRC_ITU_T, &rt2x00dev->flags)) {
+ /*
+ * Use the crc itu-t algorithm.
+ * Use 0 for the last 2 bytes to complete the checksum.
+ */
+ crc = crc_itu_t(0, fw->data, fw->size - 2);
+ crc = crc_itu_t_byte(crc, 0);
+ crc = crc_itu_t_byte(crc, 0);
+ } else if (test_bit(DRIVER_REQUIRE_FIRMWARE_CCITT, &rt2x00dev->flags)) {
+ /*
+ * Use the crc ccitt algorithm.
+ * This will return the same value as the legacy driver which
+ * used bit ordering reversion on the both the firmware bytes
+ * before input input as well as on the final output.
+ * Obviously using crc ccitt directly is much more efficient.
+ */
+ crc = crc_ccitt(~0, fw->data, fw->size - 2);
+ } else {
+ ERROR(rt2x00dev, "No checksum algorithm selected "
+ "for firmware validation.\n");
+ retval = -ENOENT;
+ goto exit;
+ }
if (crc != (fw->data[fw->size - 2] << 8 | fw->data[fw->size - 1])) {
- ERROR(rt2x00dev, "Firmware CRC error.\n");
+ ERROR(rt2x00dev, "Firmware checksum error.\n");
retval = -ENOENT;
goto exit;
}
@@ -96,6 +116,9 @@ int rt2x00lib_load_firmware(struct rt2x00_dev *rt2x00dev)
{
int retval;
+ if (!test_bit(DRIVER_REQUIRE_FIRMWARE, &rt2x00dev->flags))
+ return 0;
+
if (!rt2x00dev->fw) {
retval = rt2x00lib_request_firmware(rt2x00dev);
if (retval)
diff --git a/drivers/net/wireless/rt2x00/rt61pci.c b/drivers/net/wireless/rt2x00/rt61pci.c
index fc5acdf..6c97361 100644
--- a/drivers/net/wireless/rt2x00/rt61pci.c
+++ b/drivers/net/wireless/rt2x00/rt61pci.c
@@ -2255,9 +2255,10 @@ static int rt61pci_probe_hw(struct rt2x00_dev *rt2x00dev)
rt61pci_probe_hw_mode(rt2x00dev);
/*
- * This device requires firmware
+ * This device requires firmware.
*/
__set_bit(DRIVER_REQUIRE_FIRMWARE, &rt2x00dev->flags);
+ __set_bit(DRIVER_REQUIRE_FIRMWARE_CRC_ITU_T, &rt2x00dev->flags);
/*
* Set the rssi offset.
diff --git a/drivers/net/wireless/rt2x00/rt73usb.c b/drivers/net/wireless/rt2x00/rt73usb.c
index 2231557..01c020b 100644
--- a/drivers/net/wireless/rt2x00/rt73usb.c
+++ b/drivers/net/wireless/rt2x00/rt73usb.c
@@ -1846,9 +1846,10 @@ static int rt73usb_probe_hw(struct rt2x00_dev *rt2x00dev)
rt73usb_probe_hw_mode(rt2x00dev);
/*
- * This device requires firmware
+ * This device requires firmware.
*/
__set_bit(DRIVER_REQUIRE_FIRMWARE, &rt2x00dev->flags);
+ __set_bit(DRIVER_REQUIRE_FIRMWARE_CRC_ITU_T, &rt2x00dev->flags);
/*
* Set the rssi offset.
--
1.5.3.8
-
To unsubscribe from this list: send the line "unsubscribe linux-wireless" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
