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rt2x00: Driver requiring firmware should select crc algo 

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@gmail.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>
This commit is contained in:
Ivo van Doorn 2008-02-03 15:48:38 +01:00 committed by John W. Linville
parent adfdbb79c0
commit 9404ef34e4
6 changed files with 42 additions and 16 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

1
drivers/net/wireless/rt2x00/Kconfig
View File

@ -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

2
drivers/net/wireless/rt2x00/rt2x00.h
View File

@ -551,6 +551,8 @@ 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,

8
drivers/net/wireless/rt2x00/rt2x00dev.c
View File

@ -1017,11 +1017,9 @@ 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.

41
drivers/net/wireless/rt2x00/rt2x00firmware.c
View File

@ -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)

3
drivers/net/wireless/rt2x00/rt61pci.c
View File

@ -2258,9 +2258,10 @@ 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.

3
drivers/net/wireless/rt2x00/rt73usb.c
View File

@ -1849,9 +1849,10 @@ 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.