2012-11-16 03:05:58

by Jun Chen

Subject: [PATCH] serial: ifx6x60: ifx_spi_write don't need to do mrdy_assert when fifo is not empty.

This patch check whether the fifo lenth is empty before writing new data to fifo.If condition
is true,ifx_spi_write need to trigger one mrdy_assert. If condition is false,the mrdy_assert
will be trigger by the next ifx_spi_io.
Cc: Bi Chao <[email protected]>
Signed-off-by: Chen Jun <[email protected]>
---
drivers/tty/serial/ifx6x60.c | 14 +++++++++++---
1 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/drivers/tty/serial/ifx6x60.c b/drivers/tty/serial/ifx6x60.c
index 5b9bc19..aa01989 100644
--- a/drivers/tty/serial/ifx6x60.c
+++ b/drivers/tty/serial/ifx6x60.c
@@ -469,9 +469,17 @@ static int ifx_spi_write(struct tty_struct *tty, const unsigned char *buf,
{
struct ifx_spi_device *ifx_dev = tty->driver_data;
unsigned char *tmp_buf = (unsigned char *)buf;
- int tx_count = kfifo_in_locked(&ifx_dev->tx_fifo, tmp_buf, count,
- &ifx_dev->fifo_lock);
- mrdy_assert(ifx_dev);
+ int tx_count;
+ unsigned long flags;
+ bool is_fifo_empty;
+
+ spin_lock_irqsave(&ifx_dev->fifo_lock, flags);
+ is_fifo_empty = kfifo_is_empty(&ifx_dev->tx_fifo);
+ tx_count = kfifo_in(&ifx_dev->tx_fifo, tmp_buf, count);
+ spin_unlock_irqrestore(&ifx_dev->fifo_lock, flags);
+ if (is_fifo_empty)
+ mrdy_assert(ifx_dev);
+
return tx_count;
}

--
1.7.4.1

2012-11-16 12:37:47

by Greg Kroah-Hartman

Subject: Re: [PATCH] serial: ifx6x60: ifx_spi_write don't need to do mrdy_assert when fifo is not empty.

On Fri, Nov 16, 2012 at 06:08:37AM -0500, Jun Chen wrote:
>
> This patch check whether the fifo lenth is empty before writing new data to fifo.If condition
> is true,ifx_spi_write need to trigger one mrdy_assert. If condition is false,the mrdy_assert
> will be trigger by the next ifx_spi_io.
>
> Cc: Bi Chao <[email protected]>
> Signed-off-by: Chen Jun <[email protected]>
> ---
> drivers/tty/serial/ifx6x60.c | 14 +++++++++++---
> 1 files changed, 11 insertions(+), 3 deletions(-)

What tree did you make this against? It doesn't apply to my tty-next
tree at all :(

greg k-h

2012-11-18 03:14:35

by Jun Chen

Subject: RE: [PATCH] serial: ifx6x60: ifx_spi_write don't need to do mrdy_assert when fifo is not empty.

Hi,
I make this patch on your tty-next tree, Do I need to make it on the branch 3.7-rc6 against?

-----Original Message-----
From: Greg KH [mailto:[email protected]]
Sent: Friday, November 16, 2012 8:39 PM
To: Chen, Jun D
Cc: Alan Cox; Bi, Chao; serial; Gorby, Russ; [email protected]; Wu, Fengguang
Subject: Re: [PATCH] serial: ifx6x60: ifx_spi_write don't need to do mrdy_assert when fifo is not empty.

On Fri, Nov 16, 2012 at 06:08:37AM -0500, Jun Chen wrote:
>
> This patch check whether the fifo lenth is empty before writing new
> data to fifo.If condition is true,ifx_spi_write need to trigger one
> mrdy_assert. If condition is false,the mrdy_assert will be trigger by the next ifx_spi_io.
>
> Cc: Bi Chao <[email protected]>
> Signed-off-by: Chen Jun <[email protected]>
> ---
> drivers/tty/serial/ifx6x60.c | 14 +++++++++++---
> 1 files changed, 11 insertions(+), 3 deletions(-)

What tree did you make this against? It doesn't apply to my tty-next tree at all :(

greg k-h

2012-11-18 03:29:20

by Greg Kroah-Hartman

Subject: Re: [PATCH] serial: ifx6x60: ifx_spi_write don't need to do mrdy_assert when fifo is not empty.

http://daringfireball.net/2007/07/on_top

On Sun, Nov 18, 2012 at 03:14:28AM +0000, Chen, Jun D wrote:
> Hi,
> I make this patch on your tty-next tree, Do I need to make it on the branch 3.7-rc6 against?

No, my tty-next branch. But something is odd, it didn't apply at all.
Please try again.

thanks,

greg k-h