linux-i2c.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Nicola Corna <nicola@corna.info>
To: Wolfram Sang <wsa@the-dreams.de>,
	Stephen Warren <swarren@wwwdotorg.org>,
	Lee Jones <lee@kernel.org>, Eric Anholt <eric@anholt.net>,
	Jonathan Cameron <jic23@kernel.org>
Cc: Nicola Corna <nicola@corna.info>,
	Lars-Peter Clausen <lars@metafoo.de>,
	linux-iio@vger.kernel.org, linux-i2c@vger.kernel.org,
	Peter Meerwald <pmeerw@pmeerw.net>,
	Hartmut Knaack <knaack.h@gmx.de>,
	linux-arm-kernel@lists.infradead.org,
	linux-rpi-kernel@lists.infradead.org
Subject: [PATCH v2 3/5] i2c: add I2C_AQ_NO_CLK_STRETCH to i2c-bcm2835.c
Date: Thu, 29 Oct 2015 12:34:25 +0100	[thread overview]
Message-ID: <1446118467-26453-3-git-send-email-nicola@corna.info> (raw)
In-Reply-To: <1446118467-26453-1-git-send-email-nicola@corna.info>

As reported here
http://www.advamation.com/knowhow/raspberrypi/rpi-i2c-bug.html
and confirmed here
https://www.raspberrypi.org/forums/viewtopic.php?p=146272
the BCM2835 has a hardware bug in its i2c module which prevents a correct
clock stretching. This patch adds the I2C_AQ_NO_CLK_STRETCH quirk flag
to i2c-bcm2835.

Signed-off-by: Nicola Corna <nicola@corna.info>
---
 drivers/i2c/busses/i2c-bcm2835.c | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/drivers/i2c/busses/i2c-bcm2835.c b/drivers/i2c/busses/i2c-bcm2835.c
index 3032b89..38d7102 100644
--- a/drivers/i2c/busses/i2c-bcm2835.c
+++ b/drivers/i2c/busses/i2c-bcm2835.c
@@ -222,6 +222,10 @@ static const struct i2c_algorithm bcm2835_i2c_algo = {
 	.functionality	= bcm2835_i2c_func,
 };
 
+static const struct i2c_adapter_quirks bcm2835_i2c_quirks = {
+	.flags = I2C_AQ_NO_CLK_STRETCH,
+};
+
 static int bcm2835_i2c_probe(struct platform_device *pdev)
 {
 	struct bcm2835_i2c_dev *i2c_dev;
@@ -293,6 +297,7 @@ static int bcm2835_i2c_probe(struct platform_device *pdev)
 	adap->algo = &bcm2835_i2c_algo;
 	adap->dev.parent = &pdev->dev;
 	adap->dev.of_node = pdev->dev.of_node;
+	adap->quirks = &bcm2835_i2c_quirks;
 
 	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_C, 0);
 
-- 
2.6.1

  parent reply	other threads:[~2015-10-29 11:34 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-10-27 20:11 [PATCH 1/4] i2c: added i2c quirk flag for unsupported clock stretching Nicola Corna
2015-10-27 20:11 ` [PATCH 2/4] i2c: added I2C_AQ_NO_CLK_STRETCH to i2c-algo-bit.c Nicola Corna
2015-10-27 20:11 ` [PATCH 3/4] i2c: added I2C_AQ_NO_CLK_STRETCH to i2c-bcm2835.c Nicola Corna
     [not found]   ` <1445976718-7449-3-git-send-email-nicola-V0pQiMyom5mh6J55Ss3d3w@public.gmane.org>
2015-10-28 19:16     ` Eric Anholt
2015-10-29  4:10   ` Stephen Warren
2015-10-27 20:11 ` [PATCH v3 4/4] iio: humidity: si7020: added No Hold read mode Nicola Corna
2015-10-27 23:30   ` Wolfram Sang
2015-10-28  6:46   ` Nicola Corna
2015-10-28  6:58     ` [PATCH v4 " Nicola Corna
     [not found]       ` <1446015506-21371-1-git-send-email-nicola-V0pQiMyom5mh6J55Ss3d3w@public.gmane.org>
2015-10-28  9:38         ` Lars-Peter Clausen
2015-10-28 18:35       ` Nicola Corna
2015-10-28 18:46         ` Lars-Peter Clausen
2015-10-28 20:17         ` Nicola Corna
     [not found]         ` <563117FB.5030506-Qo5EllUWu/uELgA04lAiVw@public.gmane.org>
2015-10-28 20:19           ` Nicola Corna
2015-10-29  9:17             ` Lars-Peter Clausen
2015-10-29 11:34 ` [PATCH v2 1/5] i2c: add i2c quirk flag for unsupported clock stretching Nicola Corna
2015-10-29 11:34   ` [PATCH v2 2/5] i2c: add I2C_AQ_NO_CLK_STRETCH to i2c-algo-bit.c Nicola Corna
     [not found]     ` <1446118467-26453-2-git-send-email-nicola-V0pQiMyom5mh6J55Ss3d3w@public.gmane.org>
2015-11-30 17:26       ` Wolfram Sang
2015-10-29 11:34   ` Nicola Corna [this message]
2015-11-30 17:27     ` [PATCH v2 3/5] i2c: add I2C_AQ_NO_CLK_STRETCH to i2c-bcm2835.c Wolfram Sang
2015-10-29 11:34   ` [PATCH 4/5] i2c: add i2c_check_quirks helper function Nicola Corna
     [not found]     ` <1446118467-26453-4-git-send-email-nicola-V0pQiMyom5mh6J55Ss3d3w@public.gmane.org>
2015-10-31 10:18       ` Jonathan Cameron
     [not found]         ` <56349581.8070900-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
2015-11-30 17:28           ` Wolfram Sang
2015-11-30 17:30     ` Wolfram Sang
2015-10-29 11:34   ` [PATCH v5 5/5] iio: humidity: si7020: add No Hold read mode Nicola Corna
2015-10-31 10:21     ` Jonathan Cameron
     [not found]       ` <56349644.2060308-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org>
2015-11-30 17:33         ` Wolfram Sang
2015-12-05 18:24           ` Jonathan Cameron
2015-12-05 19:01             ` Wolfram Sang
2015-11-30 17:24   ` [PATCH v2 1/5] i2c: add i2c quirk flag for unsupported clock stretching Wolfram Sang

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=1446118467-26453-3-git-send-email-nicola@corna.info \
    --to=nicola@corna.info \
    --cc=eric@anholt.net \
    --cc=jic23@kernel.org \
    --cc=knaack.h@gmx.de \
    --cc=lars@metafoo.de \
    --cc=lee@kernel.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-i2c@vger.kernel.org \
    --cc=linux-iio@vger.kernel.org \
    --cc=linux-rpi-kernel@lists.infradead.org \
    --cc=pmeerw@pmeerw.net \
    --cc=swarren@wwwdotorg.org \
    --cc=wsa@the-dreams.de \
    /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).