linux-spi.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>
To: linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
Cc: Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>,
	Andy Shevchenko
	<andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>,
	Mark Brown <broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
Subject: [PATCH] spi: dw: Disable clock after unregistering the host
Date: Tue, 18 Apr 2017 20:09:06 +0200	[thread overview]
Message-ID: <20170418180906.29844-1-marex@denx.de> (raw)

The dw_mmio driver disables the block clock before unregistering
the host. The code unregistering the host may access the SPI block
registers. If register access happens with block clock disabled,
this may lead to a bus hang. Disable the clock after unregistering
the host to prevent such situation.

This bug was observed on Altera Cyclone V SoC.

Signed-off-by: Marek Vasut <marex-ynQEQJNshbs@public.gmane.org>
Cc: Andy Shevchenko <andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org>
Cc: Mark Brown <broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
---
 drivers/spi/spi-dw-mmio.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/spi/spi-dw-mmio.c b/drivers/spi/spi-dw-mmio.c
index 447497e9124c..d25cc4037e23 100644
--- a/drivers/spi/spi-dw-mmio.c
+++ b/drivers/spi/spi-dw-mmio.c
@@ -115,8 +115,8 @@ static int dw_spi_mmio_remove(struct platform_device *pdev)
 {
 	struct dw_spi_mmio *dwsmmio = platform_get_drvdata(pdev);
 
-	clk_disable_unprepare(dwsmmio->clk);
 	dw_spi_remove_host(&dwsmmio->dws);
+	clk_disable_unprepare(dwsmmio->clk);
 
 	return 0;
 }
-- 
2.11.0

--
To unsubscribe from this list: send the line "unsubscribe linux-spi" in
the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html

             reply	other threads:[~2017-04-18 18:09 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-04-18 18:09 Marek Vasut [this message]
     [not found] ` <20170418180906.29844-1-marex-ynQEQJNshbs@public.gmane.org>
2017-04-18 18:17   ` Applied "spi: dw: Disable clock after unregistering the host" to the spi tree Mark Brown

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20170418180906.29844-1-marex@denx.de \
    --to=marex-ynqeqjnshbs@public.gmane.org \
    --cc=andriy.shevchenko-VuQAYsv1563Yd54FQh9/CA@public.gmane.org \
    --cc=broonie-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org \
    --cc=linux-spi-u79uwXL29TY76Z2rM5mHXA@public.gmane.org \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).