From patchwork Fri Oct  2 15:23:02 2020
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From: Christian Eggers <ceggers@arri.de>
To: Oleksij Rempel <linux@rempel-privat.de>,
 Shawn Guo <shawnguo@kernel.org>, Sascha Hauer <s.hauer@pengutronix.de>, 
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CC: Pengutronix Kernel Team <kernel@pengutronix.de>,
 NXP Linux Team <linux-imx@nxp.com>, <linux-i2c@vger.kernel.org>,
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Subject: [PATCH v2 0/3] i2c: imx: Fix handling of arbitration loss
Date: Fri, 2 Oct 2020 17:23:02 +0200
Message-ID: <20201002152305.4963-1-ceggers@arri.de>
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Changes in v2:
---------------
- Don't accidently clear additional status flags on Vybrid
  (reported by Uwe Kleine-Koenig)


On my (noisy) system, I2C arbitration losses happen quite often. In it's
current implementation, the IAL flag is partly handled, but has a
number of shortcomings:

1. The driver runs unnecessarily in a timeout when waiting for an
interrupt.

2. The driver performs 500 ms busy-waiting without any value.

3. Arbitration loss errors may be reported one transfer later than they
occured.

Best regards
Christian