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    Subject[PATCH 1/1] i2c: sh_mobile: eliminate a misreported warning
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    The warning is caused by the branches "if (pd->pos == -1)" and
    "if (pd->pos == 0)", because they appear after "real_pos = pd->pos - 2",
    so the compiler doesn't known the value of real_pos is negative through
    these two branches.

    To avoid this warning, eliminate the middleman "data".

    drivers/i2c/busses/i2c-sh_mobile.c: In function ‘sh_mobile_i2c_isr’:
    drivers/i2c/busses/i2c-sh_mobile.c:396:26: warning: ‘data’ may be used uninitialized in this function [-Wmaybe-uninitialized]
    pd->msg->buf[real_pos] = data;
    ^
    drivers/i2c/busses/i2c-sh_mobile.c:369:16: note: ‘data’ was declared here
    unsigned char data;

    Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
    ---
    drivers/i2c/busses/i2c-sh_mobile.c | 7 ++-----
    1 file changed, 2 insertions(+), 5 deletions(-)

    diff --git a/drivers/i2c/busses/i2c-sh_mobile.c b/drivers/i2c/busses/i2c-sh_mobile.c
    index d83ca4028fa0..2cca1b21e26e 100644
    --- a/drivers/i2c/busses/i2c-sh_mobile.c
    +++ b/drivers/i2c/busses/i2c-sh_mobile.c
    @@ -366,7 +366,6 @@ static int sh_mobile_i2c_isr_tx(struct sh_mobile_i2c_data *pd)

    static int sh_mobile_i2c_isr_rx(struct sh_mobile_i2c_data *pd)
    {
    - unsigned char data;
    int real_pos;

    /* switch from TX (address) to RX (data) adds two interrupts */
    @@ -387,13 +386,11 @@ static int sh_mobile_i2c_isr_rx(struct sh_mobile_i2c_data *pd)
    if (real_pos < 0)
    i2c_op(pd, OP_RX_STOP);
    else
    - data = i2c_op(pd, OP_RX_STOP_DATA);
    + pd->msg->buf[real_pos] = i2c_op(pd, OP_RX_STOP_DATA);
    } else if (real_pos >= 0) {
    - data = i2c_op(pd, OP_RX);
    + pd->msg->buf[real_pos] = i2c_op(pd, OP_RX);
    }

    - if (real_pos >= 0)
    - pd->msg->buf[real_pos] = data;
    done:
    pd->pos++;
    return pd->pos == (pd->msg->len + 2);
    --
    2.26.0.106.g9fadedd

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