linux-spi.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Brian Niebuhr <bniebuhr3-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
To: spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@public.gmane.org
Cc: david-b-yBeKhBN/0LDR7s880joybQ@public.gmane.org
Subject: [PATCH] spi: bitbang: reinitialize transfer parameters for every message
Date: Fri,  2 Jul 2010 10:30:17 -0500	[thread overview]
Message-ID: <1278084617-23027-1-git-send-email-bniebuhr@efjohnson.com> (raw)

This patch fixes the setup_transfer logic to account for the case where
multiple messages to different SPI devices are in the queue simultaneously.
With the current logic, the second message in the queue will end up
using the transfer parameters for the previous message in the queue.

The fix is to reinitialize the transfer parameters for each message
rather than only once on the first message.

Signed-off-by: Brian Niebuhr <bniebuhr-JaPwekKOx1yaMJb+Lgu22Q@public.gmane.org>
---
 drivers/spi/spi_bitbang.c |    9 +++------
 1 files changed, 3 insertions(+), 6 deletions(-)

diff --git a/drivers/spi/spi_bitbang.c b/drivers/spi/spi_bitbang.c
index 5265330..8b55724 100644
--- a/drivers/spi/spi_bitbang.c
+++ b/drivers/spi/spi_bitbang.c
@@ -259,7 +259,6 @@ static void bitbang_work(struct work_struct *work)
 	struct spi_bitbang	*bitbang =
 		container_of(work, struct spi_bitbang, work);
 	unsigned long		flags;
-	int			do_setup = -1;
 	int			(*setup_transfer)(struct spi_device *,
 					struct spi_transfer *);
 
@@ -275,6 +274,7 @@ static void bitbang_work(struct work_struct *work)
 		unsigned		tmp;
 		unsigned		cs_change;
 		int			status;
+		int			do_setup = -1;
 
 		m = container_of(bitbang->queue.next, struct spi_message,
 				queue);
@@ -307,6 +307,8 @@ static void bitbang_work(struct work_struct *work)
 				status = setup_transfer(spi, t);
 				if (status < 0)
 					break;
+				if (do_setup == -1)
+					do_setup = 0;
 			}
 
 			/* set up default clock polarity, and activate chip;
@@ -367,11 +369,6 @@ static void bitbang_work(struct work_struct *work)
 		m->status = status;
 		m->complete(m->context);
 
-		/* restore speed and wordsize if it was overridden */
-		if (do_setup == 1)
-			setup_transfer(spi, NULL);
-		do_setup = 0;
-
 		/* normally deactivate chipselect ... unless no error and
 		 * cs_change has hinted that the next message will probably
 		 * be for this chip too.
-- 
1.6.3.3


------------------------------------------------------------------------------
This SF.net email is sponsored by Sprint
What will you do first with EVO, the first 4G phone?
Visit sprint.com/first -- http://p.sf.net/sfu/sprint-com-first

             reply	other threads:[~2010-07-02 15:30 UTC|newest]

Thread overview: 3+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2010-07-02 15:30 Brian Niebuhr [this message]
     [not found] ` <1278084617-23027-1-git-send-email-bniebuhr-JaPwekKOx1yaMJb+Lgu22Q@public.gmane.org>
2010-07-02 15:37   ` [PATCH] spi: bitbang: reinitialize transfer parameters for every message Brian Niebuhr
2010-07-04  5:01   ` Grant Likely

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=1278084617-23027-1-git-send-email-bniebuhr@efjohnson.com \
    --to=bniebuhr3-re5jqeeqqe8avxtiumwx3w@public.gmane.org \
    --cc=david-b-yBeKhBN/0LDR7s880joybQ@public.gmane.org \
    --cc=spi-devel-general-5NWGOfrQmneRv+LV9MX5uipxlwaOVQ5f@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).