----- Original Message ----- From: "Andrew Morton" <[EMAIL PROTECTED]> To: "Madhusudhan Chikkature" <[EMAIL PROTECTED]> Cc: <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]>; <[email protected]> Sent: Monday, October 13, 2008 9:23 PM Subject: Re: [PATCH 1/5] HDQ Driver for OMAP2430/3430
>> On Mon, 13 Oct 2008 18:55:43 +0530 "Madhusudhan Chikkature" <[EMAIL >> PROTECTED]> wrote: >> >> ----- Original Message ----- >> From: "Andrew Morton" <[EMAIL PROTECTED]> >> To: "Gadiyar, Anand" <[EMAIL PROTECTED]> >> Cc: <[EMAIL PROTECTED]>; <[EMAIL PROTECTED]>; <[email protected]>; >> <[EMAIL PROTECTED]> >> Sent: Saturday, October 11, 2008 2:08 AM >> Subject: Re: [PATCH 1/5] HDQ Driver for OMAP2430/3430 >> >> >> >> + /* 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? > > Yes. > Yes. It is desired to return an error if the condition in the wait is not met. I need to change the check for return value to check for zero and neg value. I spent some time to test this perticular scenario.I could not really see any impact of hitting ^C when an application is transfering data in the background. When the h/w is programmed to transfer data and the driver issues a wait, I see that TXCOMPLETE interrupt comes immediately and wakes up as expected. So guess I am unable to hit ^C exactly when the driver is waiting in wait_event_interruptible_timeout(before the condition is met) for it to catch the signal. Is it generally suggested to use wait_event_timeout so that ^C signal is not caught? Regards, Madhu -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
