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From: b32955@freescale•com (Huang Shijie)
To: linux-arm-kernel@lists•infradead.org
Subject: [PATCH 1/5] serial: imx: remove unneeded imx_transmit_buffer() from imx_start_tx()
Date: Mon, 12 May 2014 14:30:50 +0800	[thread overview]
Message-ID: <53706A9A.6060707@freescale.com> (raw)
In-Reply-To: <53706014.8010203@de.bosch.com>

? 2014?05?12? 13:45, Dirk Behme ??:
> On 12.05.2014 05:40, Huang Shijie wrote:
>> ? 2014?05?09? 23:19, dean_jenkins at mentor.com ??:
>>> Use imx_start_tx() just to enable the TX interrupt. It's the job of the
>>> TX interrupt ISR to fill the transmit buffer, then. If the transmit 
>>> buffer
 From the Documentation/serial/driver, we can see:
   -----------------------------------------
    start_tx(port)
     Start transmitting characters.
    -----------------------------------------

It tells us we can transmit data in the imx_start_tx.

But this patch moves it to the interrupt handler, this patch makes the 
interrupt handler do more jobs.




>>> is empty, the TX interrupt should be executed as soon as the start_tx()
>>> enables the interrupt, so there is no reason for the extra
>>> imx_transmit_buffer() call, here. Remove it.
>> I don't know why this patch needed?
>> What problem this patch fix or improve?
>
> As stated in the commit message, the call of imx_transmit_buffer() 
> isn't needed there, so it can be removed. I.e. remove unneeded code.

>
> In the end, this cleans up the possible locking path, so that in the 
> third patch the locking issue can be easily fixed.
>
The lock issue had been fixed already. Please try the latest linux-next.
see my comment in the third patch.


thanks
Huang Shijie

  reply	other threads:[~2014-05-12  6:30 UTC|newest]

Thread overview: 18+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-05-09 15:19 [PATCH 0/5] serial: imx: fixes dean_jenkins at mentor.com
2014-05-09 15:19 ` [PATCH 1/5] serial: imx: remove unneeded imx_transmit_buffer() from imx_start_tx() dean_jenkins at mentor.com
2014-05-12  3:40   ` Huang Shijie
2014-05-12  5:45     ` Dirk Behme
2014-05-12  6:30       ` Huang Shijie [this message]
2014-05-12  6:40         ` Dirk Behme
2014-05-12  6:53           ` Huang Shijie
2014-05-12  8:03             ` Dean Jenkins
2014-05-12  8:17               ` Huang Shijie
2014-05-09 15:19 ` [PATCH 2/5] serial: imx: remove uart_write_wakeup() from imx_transmit_buffer() dean_jenkins at mentor.com
2014-05-09 15:19 ` [PATCH 3/5] serial: imx: avoid spinlock recursion deadlock dean_jenkins at mentor.com
2014-05-12  3:12   ` Huang Shijie
2014-05-14 16:24     ` Dean Jenkins
2014-05-09 15:19 ` [PATCH 4/5] serial: imx: move imx_transmit_buffer() into imx_txint() dean_jenkins at mentor.com
2014-05-09 15:19 ` [PATCH 5/5] serial: imx: clean up imx_poll_get_char() dean_jenkins at mentor.com
2014-05-28 19:34 ` [PATCH 0/5] serial: imx: fixes Greg KH
2014-05-29  4:58   ` Dirk Behme
2014-05-29  4:14     ` Huang Shijie

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