From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from relay4-d.mail.gandi.net (relay4-d.mail.gandi.net [217.70.183.196]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6EC61135A69; Thu, 15 Feb 2024 16:52:34 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.70.183.196 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708015959; cv=none; b=ntSoplI8ZbvLiLNj5dxpP5Q7XRJMr0ykUWScXooa6h9pWTsrMebalIVH8p0UEF8j5C8GTl0sptIAaqu41xGw19+ero2A28kBSQV7L+nr1ZCy9yw/opEjS/673OcDr/CBlipyFYeiWHXbzFAM1fMi3ZsMfpi+N5TONK7QKN2X0yQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1708015959; c=relaxed/simple; bh=uz+Np8+G4qWw8PU0VSBJNfx1oM1lJAFehJiEej4mz+4=; h=From:Subject:Date:Message-Id:MIME-Version:Content-Type:To:Cc; b=LZOe9xyq8VaKynrlMAj0g8i7GCtf3E4Vy9M/zagA9SwUeypNyonlmmYsoXno7ErZAbTsWMujpFjFDPIM5gVBOXfLmqeyCsPoc/o0eZw4yYjxcI4zauXKcTjD5/ITS+6wvIjj24GVbk3lG+rrs+ovCP4JneLD+UtAIqTGmcRVkek= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com; spf=pass smtp.mailfrom=bootlin.com; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b=jtRPtvNb; arc=none smtp.client-ip=217.70.183.196 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=bootlin.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=bootlin.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=bootlin.com header.i=@bootlin.com header.b="jtRPtvNb" Received: by mail.gandi.net (Postfix) with ESMTPSA id CDF77E0011; Thu, 15 Feb 2024 16:52:31 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=bootlin.com; s=gm1; t=1708015953; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=jQzNaC4fbX9njWrN3MZ96SWXHEvPGyukJ/MJUgb0Ufw=; b=jtRPtvNbikaavwuAwhIXCTXCvi72i/3fzBPBJgxgqtcU72jRmj4Gnvu88GQzqS5ktzDtUv Szm8DiTfA/Jgk2Q8EZb86VnPARemwTMraYVwkBLbfapJA9fQhOV5QIPDaVtn2LSF3k42Fn JPpRIVV5cGmnmJKfdMRzurQuzVBb853IcPg03oiVTAryYNZ/p0DrgWgGaQoyiuTtH9Ir5m kAtEhNWN3ap9+kCzJVnild5PYp5M974xw67+I3X25MV7QiYnUxzTmOdyJYLI5wiDq2OPha lqmeQFwK0crtd7nRXenqGH4Pex8d9fqvPEYTgRyqmDuDjS+CNTQVzf69px69Iw== From: =?utf-8?q?Th=C3=A9o_Lebrun?= Subject: [PATCH 00/13] Add Mobileye EyeQ5 support to the Nomadik I2C controller & use hrtimers for timeouts Date: Thu, 15 Feb 2024 17:52:07 +0100 Message-Id: <20240215-mbly-i2c-v1-0-19a336e91dca@bootlin.com> Precedence: bulk X-Mailing-List: devicetree@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 8bit X-B4-Tracking: v=1; b=H4sIADhBzmUC/6tWKk4tykwtVrJSqFYqSi3LLM7MzwNyDHUUlJIzE vPSU3UzU4B8JSMDI2NDINbNTcqp1M00StY1TzZKS0pKMjSytExTAiovKEpNy6wAGxUdW1sLAHn jwDRaAAAA To: Linus Walleij , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Thomas Bogendoerfer Cc: linux-arm-kernel@lists.infradead.org, linux-i2c@vger.kernel.org, devicetree@vger.kernel.org, linux-kernel@vger.kernel.org, linux-mips@vger.kernel.org, Gregory Clement , Vladimir Kondratiev , Thomas Petazzoni , Tawfik Bayouk , =?utf-8?q?Th=C3=A9o_Lebrun?= , Jean Delvare , Guenter Roeck , linux-hwmon@vger.kernel.org X-Mailer: b4 0.12.4 X-GND-Sasl: theo.lebrun@bootlin.com Hi, This series adds two tangent features to the Nomadik I2C controller: - Add a new compatible to support Mobileye EyeQ5 which uses the same IP block as Nomadik. It has two quirks to be handled: - The memory bus only supports 32-bit accesses. A writeb() is used which we avoid. - We must write a value into a shared register region (OLB, "Other Logic Block") depending on the I2C bus speed. - Allow xfer timeouts below one jiffy by using a workqueue and hrtimers instead of a completion. The situation to be addressed is: - Many devices on the same I2C bus. - One xfer to each device is sent at regular interval. - One device gets stuck and does not answer. - With long timeouts, following devices won't get their message. A shorter timeout ensures we can still talk to the following devices. This clashes a bit with the current i2c_adapter timeout field that stores a jiffies amount. We cannot rely on it and therefore we take a value from devicetree as a µs value. If the timeout is less than a jiffy duration, we switch from standard jiffies timeout to hrtimers. There is one patch targeting a hwmon dt-bindings file: Documentation/devicetree/bindings/hwmon/lm75.yaml. The rest is touching the I2C bus driver, its bindings and platform devicetrees. About dependencies: - The series is based upon v6.8-rc4. - For testing on EyeQ5 hardware and devicetree patches, we need the base platform series from Grégory [0]. - The last commit (adding DT phandles for resets), we need the syscon series [1] that provides the reset controller node. I think there are discussions to be had about: - The handling of timeouts. Having a non-jiffy value is not driver specific. Should this change be done at the subsystem layer? The subsystem could even fetch the value from devicetree and auto-fill timeout, with a default given by the driver. Not many drivers seem to use the i2c_adapter timeout field from my quick grepping. - The DT prop for timeout. I've picked "timeout-usecs". Some drivers use vendor prefixes, but this is not vendor-specific and only a software implementation detail. - The shape of this series. Initially it was split in two. However I brought them together as they cannot be applied independently. Please tell me if a better approach is to be preferred. Those are thoughts, I'm sure people will have feedback on this. Have a nice day, Théo Lebrun [0]: https://lore.kernel.org/lkml/20240205153503.574468-1-gregory.clement@bootlin.com/ [1]: https://lore.kernel.org/lkml/20240212-mbly-clk-v6-0-c46fa1f93839@bootlin.com/ Signed-off-by: Théo Lebrun --- Théo Lebrun (13): dt-bindings: i2c: nomadik: add timeout-usecs property bindings dt-bindings: i2c: nomadik: add mobileye,eyeq5-i2c bindings and example dt-bindings: hwmon: lm75: add label property i2c: nomadik: rename private struct pointers from dev to priv i2c: nomadik: simplify IRQ masking logic i2c: nomadik: use bitops helpers i2c: nomadik: support short xfer timeouts using waitqueue & hrtimer i2c: nomadik: replace jiffies by ktime for FIFO flushing timeout i2c: nomadik: fetch timeout-usecs property from devicetree i2c: nomadik: support Mobileye EyeQ5 I2C controller MIPS: mobileye: eyeq5: add 5 I2C controller nodes MIPS: mobileye: eyeq5: add evaluation board I2C temp sensor MIPS: mobileye: eyeq5: add resets to I2C controllers Documentation/devicetree/bindings/hwmon/lm75.yaml | 4 + .../devicetree/bindings/i2c/st,nomadik-i2c.yaml | 49 +- arch/mips/boot/dts/mobileye/eyeq5-epm5.dts | 8 + arch/mips/boot/dts/mobileye/eyeq5.dtsi | 75 +++ drivers/i2c/busses/i2c-nomadik.c | 710 ++++++++++++--------- 5 files changed, 534 insertions(+), 312 deletions(-) --- base-commit: d55aa725e32849f709b61eab3b7a50b810a71a84 change-id: 20231023-mbly-i2c-7c2fbbb1299f Best regards, -- Théo Lebrun