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| author |   Bartosz Golaszewski <brgl@bgdev.pl> | 2017-11-27 22:06:13 +0100 |
|---|---|---|
| committer | Bartosz Golaszewski <brgl@bgdev.pl> | 2017-11-29 15:22:24 +0100 |
| commit | 5478e478eee3b096b8d998d4ed445da30da2dfbc (patch) | |
| tree | e1652fdf308cef6a7cedc152dc519897a822b88a /drivers/misc | |
| parent | Linux 4.15-rc1 (diff) | |
| download | linux-dev-5478e478eee3b096b8d998d4ed445da30da2dfbc.tar.xz linux-dev-5478e478eee3b096b8d998d4ed445da30da2dfbc.zip | |
eeprom: at24: correctly set the size for at24mac402
There's an ilog2() expansion in AT24_DEVICE_MAGIC() which rounds down
the actual size of EUI-48 byte array in at24mac402 eeproms to 4 from 6,
making it impossible to read it all.
Fix it by manually adjusting the value in probe().
This patch contains a temporary fix that is suitable for stable
branches. Eventually we'll probably remove the call to ilog2() while
converting the magic values to actual structs.
Cc: stable@vger.kernel.org
Fixes: 0b813658c115 ("eeprom: at24: add support for at24mac series")
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Reviewed-by: Andy Shevchenko <andy.shevchenko@gmail.com>
Diffstat (limited to 'drivers/misc')
| -rw-r--r-- | drivers/misc/eeprom/at24.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/misc/eeprom/at24.c b/drivers/misc/eeprom/at24.c index e0b4b36ef010..783244b485cc 100644 --- a/drivers/misc/eeprom/at24.c +++ b/drivers/misc/eeprom/at24.c @@ -730,6 +730,16 @@ static int at24_probe(struct i2c_client *client, const struct i2c_device_id *id) dev_warn(&client->dev, "page_size looks suspicious (no power of 2)!\n"); + /* + * REVISIT: the size of the EUI-48 byte array is 6 in at24mac402, while + * the call to ilog2() in AT24_DEVICE_MAGIC() rounds it down to 4. + * + * Eventually we'll get rid of the magic values altoghether in favor of + * real structs, but for now just manually set the right size. + */ + if (chip.flags & AT24_FLAG_MAC && chip.byte_len == 4) + chip.byte_len = 6; + /* Use I2C operations unless we're stuck with SMBus extensions. */ if (!i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) { if (chip.flags & AT24_FLAG_ADDR16) |