lkml.org 
[lkml]   [2011]   [Nov]   [3]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    Patch in this message
    /
    Date
    From
    Subject[PATCH] lis3lv02d: Avoid zero-division
    In some weird situation, HP DriveGuard chip can't read ODR value
    correctly, and it results in a zero-division Oops in lis3lv02d driver.
    This patch fixes the Oops by checking the value appopriately, and skips
    if any weird value is read.

    Cc: <stable@kernel.org>
    Signed-off-by: Takashi Iwai <tiwai@suse.de>
    ---
    drivers/misc/lis3lv02d/lis3lv02d.c | 14 +++++++++++---
    1 files changed, 11 insertions(+), 3 deletions(-)

    diff --git a/drivers/misc/lis3lv02d/lis3lv02d.c b/drivers/misc/lis3lv02d/lis3lv02d.c
    index 8b51cd6..c4eb2f3 100644
    --- a/drivers/misc/lis3lv02d/lis3lv02d.c
    +++ b/drivers/misc/lis3lv02d/lis3lv02d.c
    @@ -228,6 +228,14 @@ static int lis3lv02d_set_odr(int rate)
    return -EINVAL;
    }

    +static void lis3lv02d_power_delay(struct lis3lv02d *lis3)
    +{
    + int odr = lis3lv02d_get_odr();
    + if (odr <= 0)
    + return;
    + msleep(lis3->pwron_delay / odr);
    +}
    +
    static int lis3lv02d_selftest(struct lis3lv02d *lis3, s16 results[3])
    {
    u8 ctlreg, reg;
    @@ -266,7 +274,7 @@ static int lis3lv02d_selftest(struct lis3lv02d *lis3, s16 results[3])

    lis3->read(lis3, ctlreg, &reg);
    lis3->write(lis3, ctlreg, (reg | selftest));
    - msleep(lis3->pwron_delay / lis3lv02d_get_odr());
    + lis3lv02d_power_delay(lis3);

    /* Read directly to avoid axis remap */
    x = lis3->read_data(lis3, OUTX);
    @@ -275,7 +283,7 @@ static int lis3lv02d_selftest(struct lis3lv02d *lis3, s16 results[3])

    /* back to normal settings */
    lis3->write(lis3, ctlreg, reg);
    - msleep(lis3->pwron_delay / lis3lv02d_get_odr());
    + lis3lv02d_power_delay(lis3);

    results[0] = x - lis3->read_data(lis3, OUTX);
    results[1] = y - lis3->read_data(lis3, OUTY);
    @@ -385,7 +393,7 @@ void lis3lv02d_poweron(struct lis3lv02d *lis3)
    }

    /* LIS3 power on delay is quite long */
    - msleep(lis3->pwron_delay / lis3lv02d_get_odr());
    + lis3lv02d_power_delay(lis3);

    if (lis3->reg_ctrl)
    lis3_context_restore(lis3);
    --
    1.7.7


    \
     
     \ /
      Last update: 2011-11-03 13:11    [W:0.022 / U:30.988 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site