V4L/DVB: media: dvb/af9015, implement eeprom hashing

This will be useful for matching of IR tables later.

We read the eeprom anyway for dumping. Switch the dumping to
print_hex_dump_bytes and compute hash above that by
hash = 0;
for (u32 VAL) in (eeprom):
  hash *= GOLDEN_RATIO_PRIME_32
  hash += VAL; // while preserving endinaness

The computation is moved earlier to the flow, namely from
af9015_af9013_frontend_attach to af9015_read_config, so that
we can access the sum in af9015_read_config already.

Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Acked-by: Antti Palosaari <crope@iki.fi>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
This commit is contained in:
Jiri Slaby 2010-01-22 12:10:52 -03:00 committed by Mauro Carvalho Chehab
parent 0b32d65cd7
commit 6c614044ff
2 changed files with 44 additions and 22 deletions

View file

@ -21,6 +21,8 @@
*
*/
#include <linux/hash.h>
#include "af9015.h"
#include "af9013.h"
#include "mt2060.h"
@ -553,26 +555,45 @@ exit:
return ret;
}
/* dump eeprom */
static int af9015_eeprom_dump(struct dvb_usb_device *d)
/* hash (and dump) eeprom */
static int af9015_eeprom_hash(struct usb_device *udev)
{
u8 reg, val;
static const unsigned int eeprom_size = 256;
unsigned int reg;
int ret;
u8 val, *eeprom;
struct req_t req = {READ_I2C, AF9015_I2C_EEPROM, 0, 0, 1, 1, &val};
for (reg = 0; ; reg++) {
if (reg % 16 == 0) {
if (reg)
deb_info(KERN_CONT "\n");
deb_info(KERN_DEBUG "%02x:", reg);
}
if (af9015_read_reg_i2c(d, AF9015_I2C_EEPROM, reg, &val) == 0)
deb_info(KERN_CONT " %02x", val);
else
deb_info(KERN_CONT " --");
if (reg == 0xff)
break;
eeprom = kmalloc(eeprom_size, GFP_KERNEL);
if (eeprom == NULL)
return -ENOMEM;
for (reg = 0; reg < eeprom_size; reg++) {
req.addr = reg;
ret = af9015_rw_udev(udev, &req);
if (ret)
goto free;
eeprom[reg] = val;
}
deb_info(KERN_CONT "\n");
return 0;
if (dvb_usb_af9015_debug & 0x01)
print_hex_dump_bytes("", DUMP_PREFIX_OFFSET, eeprom,
eeprom_size);
BUG_ON(eeprom_size % 4);
af9015_config.eeprom_sum = 0;
for (reg = 0; reg < eeprom_size / sizeof(u32); reg++) {
af9015_config.eeprom_sum *= GOLDEN_RATIO_PRIME_32;
af9015_config.eeprom_sum += le32_to_cpu(((u32 *)eeprom)[reg]);
}
deb_info("%s: eeprom sum=%.8x\n", __func__, af9015_config.eeprom_sum);
ret = 0;
free:
kfree(eeprom);
return ret;
}
static int af9015_download_ir_table(struct dvb_usb_device *d)
@ -728,6 +749,11 @@ static int af9015_read_config(struct usb_device *udev)
}
if (ret)
goto error;
ret = af9015_eeprom_hash(udev);
if (ret)
goto error;
deb_info("%s: IR mode:%d\n", __func__, val);
for (i = 0; i < af9015_properties_count; i++) {
if (val == AF9015_IR_MODE_DISABLED) {
@ -1125,11 +1151,6 @@ static int af9015_af9013_frontend_attach(struct dvb_usb_adapter *adap)
deb_info("%s: init I2C\n", __func__);
ret = af9015_i2c_init(adap->dev);
/* dump eeprom (debug) */
ret = af9015_eeprom_dump(adap->dev);
if (ret)
return ret;
} else {
/* select I2C adapter */
i2c_adap = &state->i2c_adap;

View file

@ -107,6 +107,7 @@ struct af9015_config {
u16 mt2060_if1[2];
u16 firmware_size;
u16 firmware_checksum;
u32 eeprom_sum;
u8 *ir_table;
u16 ir_table_size;
};