lkml.org 
[lkml]   [2017]   [Dec]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    From
    Subject[PATCH 4.9 21/38] eeprom: at24: correctly set the size for at24mac402
    Date
    4.9-stable review patch.  If anyone has any objections, please let me know.

    ------------------

    From: Bartosz Golaszewski <brgl@bgdev.pl>

    commit 5478e478eee3b096b8d998d4ed445da30da2dfbc upstream.

    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.

    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>
    Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    ---
    drivers/misc/eeprom/at24.c | 10 ++++++++++
    1 file changed, 10 insertions(+)

    --- a/drivers/misc/eeprom/at24.c
    +++ b/drivers/misc/eeprom/at24.c
    @@ -639,6 +639,16 @@ static int at24_probe(struct i2c_client
    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)

    \
     
     \ /
      Last update: 2017-12-04 17:34    [W:3.736 / U:0.008 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site