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    SubjectRe: [PATCH 1/5] HDQ Driver for OMAP2430/3430
    Hi.

    On Mon, Oct 13, 2008 at 06:55:43PM +0530, Madhusudhan Chikkature (madhu.cr@ti.com) wrote:
    > >> +static int hdq_write_byte(struct hdq_data *hdq_data, u8 val, u8 *status)
    > >> +{
    > >> + int ret;
    > >> + u8 tmp_status;
    > >> + unsigned long irqflags;
    > >> +
    > >> + *status = 0;
    > >> +
    > >> + spin_lock_irqsave(&hdq_data->hdq_spinlock, irqflags);
    > >> + /* clear interrupt flags via a dummy read */
    > >> + hdq_reg_in(hdq_data, OMAP_HDQ_INT_STATUS);
    > >> + /* ISR loads it with new INT_STATUS */
    > >> + hdq_data->hdq_irqstatus = 0;
    > >> + spin_unlock_irqrestore(&hdq_data->hdq_spinlock, irqflags);
    > >> +
    > >> + hdq_reg_out(hdq_data, OMAP_HDQ_TX_DATA, val);
    > >> +
    > >> + /* set the GO bit */
    > >> + hdq_reg_merge(hdq_data, OMAP_HDQ_CTRL_STATUS, OMAP_HDQ_CTRL_STATUS_GO,
    > >> + OMAP_HDQ_CTRL_STATUS_DIR | OMAP_HDQ_CTRL_STATUS_GO);
    > >> + /* wait for the TXCOMPLETE bit */
    > >> + ret = wait_event_interruptible_timeout(hdq_wait_queue,
    > >> + hdq_data->hdq_irqstatus, OMAP_HDQ_TIMEOUT);
    > >> + if (ret < 0) {
    > >> + dev_dbg(hdq_data->dev, "wait interrupted");
    > >> + return -EINTR;
    > >> + }
    > >
    > > Is this desirable? The user hits ^C and the driver bails out?
    > >
    > > I assume so, but was this tested?
    >
    > Andrew, What is the test scenario you mean here? A user hitting ^C when the driver is waiting for the TXCOMPLETE bit?

    Just plain return looks suspicious, is there some kind of a race between
    calling code (which for example frees hdq_data) and the path, which sets
    the bit and wakes up this thread?

    --
    Evgeniy Polyakov


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