From patchwork Sun May 10 09:50:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Serge Semin X-Patchwork-Id: 11539113 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 877DB912 for ; Sun, 10 May 2020 09:50:32 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7339B24955 for ; Sun, 10 May 2020 09:50:32 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728786AbgEJJuc (ORCPT ); Sun, 10 May 2020 05:50:32 -0400 Received: from mail.baikalelectronics.com ([87.245.175.226]:45846 "EHLO mail.baikalelectronics.ru" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726863AbgEJJub (ORCPT ); Sun, 10 May 2020 05:50:31 -0400 Received: from localhost (unknown [127.0.0.1]) by mail.baikalelectronics.ru (Postfix) with ESMTP id 77A0E80307CB; Sun, 10 May 2020 09:50:24 +0000 (UTC) X-Virus-Scanned: amavisd-new at baikalelectronics.ru Received: from mail.baikalelectronics.ru ([127.0.0.1]) by localhost (mail.baikalelectronics.ru [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id fTddCm_mLQ0g; Sun, 10 May 2020 12:50:23 +0300 (MSK) From: Serge Semin To: Jarkko Nikula CC: Serge Semin , Serge Semin , Alexey Malahov , Maxim Kaurkin , Pavel Parkhomenko , Ramil Zaripov , Ekaterina Skachko , Vadim Vlasov , Alexey Kolotnikov , Thomas Bogendoerfer , Paul Burton , Ralf Baechle , Andy Shevchenko , Mika Westerberg , Rob Herring , Wolfram Sang , , , , Subject: [PATCH v2 00/12] i2c: designeware: Add Baikal-T1 System I2C support Date: Sun, 10 May 2020 12:50:06 +0300 Message-ID: <20200510095019.20981-1-Sergey.Semin@baikalelectronics.ru> In-Reply-To: <20200306132001.1B875803087C@mail.baikalelectronics.ru> References: <20200306132001.1B875803087C@mail.baikalelectronics.ru> MIME-Version: 1.0 X-ClientProxiedBy: MAIL.baikal.int (192.168.51.25) To mail (192.168.51.25) Sender: linux-mips-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-mips@vger.kernel.org Initially this has been a small patchset which embedded the Baikal-T1 System I2C support into the DW APB I2C driver as is by using a simplest way. After a short discussion with Andy we decided to implement what he suggested (introduce regmap-based accessors and create a glue driver) and even more than that to provide some cleanups of the code. So here is what this patchset consists of. First of all we've found out that current implementation of scripts/dtc didn't support i2c dt nodes with 10bit and slave flags set in the reg property. You'll see an error if you try to dt_binding_check it. So the very first patch fixes the problem by adding these flags support into the check_i2c_bus_reg() method. Traditionally we converted the plain text-based DT binding to the DT schema and added Baikal-T1 System I2C device support there. This required to mark the reg property redundant for Baikal-T1 I2C since its reg-space is indirectly accessed by means of the System Controller cmd/read/write registers. Then as Andy suggested we replaced the Synopsys DW APB I2C common driver registers IO accessors into the regmap API methods. This doesn't change the code logic much, though in two places we managed to replace some bulky peaces of code with a ready-to-use regmap methods. Additionally before adding the glue layer API we initiated a set of cleanups: - Define components of the multi-object drivers (like i2c-designware-core.o and i2c-designware-paltform.o) with using `-y` suffixed makefile variables instead of `-objs` suffixed one. This is encouraged by Documentation/kbuild/makefiles.rst text since `-objs` is supposed to be used to build host programs. - Make DW I2C slave driver depended on the DW I2C core code instead of the platform one, which it really is. - Move Intel Baytrail semaphore feature to the platform if-clause of the kernel config. After this we finally can introduce the glue layer API for the DW APB I2C platform driver. So there are three methods exported from the driver: i2c_dw_plat_setup(), i2c_dw_plat_clear(), &i2c_dw_plat_dev_pm_ops to setup, cleanup and add PM operations to the glue driven I2C device. Before setting the platform DW I2C device up the glue probe code is supposed to create an instance of DW I2C device generic object and pre-initialize its `struct device` pointer together with optional platform-specific flags. In addition to that we converted the MSCC Ocelot SoC I2C specific code into the glue layer seeing it's really too specific and, which is more important, isn't that complicated so we could unpin it without much of worrying to break something. Meanwhile we discovered that MODEL_CHERRYTRAIL and MODEL_MASK actually were no longer used in the code. MODEL_MSCC flag has been discarded since the MSCC Ocelot I2C code conversion to the glue driver. So now we can get rid of all the MODEL-specific flags. Finally we introduced a glue driver with Baikal-T1 System I2C device support. The driver probe tries to find a syscon regmap, creates the DW APB I2C regmap based on it and passes it further to the DW I2C device descriptor. Then it does normal DW APB I2C platform setup by calling a generic setup method. Cleanup is straightforward. It's just calling a generic DW APB I2C clean method. This patchset is rebased and tested on the mainline Linux kernel 5.6-rc4: base-commit: 0e698dfa2822 ("Linux 5.7-rc4") tag: v5.7-rc4 Note new vendor prefix for Baikal-T1 System I2C device will be added in the framework of the next patchset: https://lkml.org/lkml/2020/5/6/1047 Signed-off-by: Serge Semin Cc: Alexey Malahov Cc: Maxim Kaurkin Cc: Pavel Parkhomenko Cc: Ramil Zaripov Cc: Ekaterina Skachko Cc: Vadim Vlasov Cc: Alexey Kolotnikov Cc: Thomas Bogendoerfer Cc: Paul Burton Cc: Ralf Baechle Cc: Andy Shevchenko Cc: Mika Westerberg Cc: Rob Herring Cc: Wolfram Sang Cc: linux-mips@vger.kernel.org Cc: linux-i2c@vger.kernel.org Cc: devicetree@vger.kernel.org Cc: linux-kernel@vger.kernel.org --- Changelog v2: - Fix the SoB tags. - Use a shorter summary describing the bindings convertion patch. - Patch "i2c: designware: Detect the FIFO size in the common code" has been acked by Jarkko and applied by Wolfram to for-next so drop it from the set. - Patch "i2c: designware: Discard i2c_dw_read_comp_param() function" has been acked by Jarkko and applied by Wolfram to for-next so drop it from the set. - Make sure that "mscc,ocelot-i2c" compatible node may have up to two registers space defined in the DT node, while normal DW I2C controller will have only one registers space. - Add "mscc,ocelot-i2c" DT schema example to test the previous fix. - Declare "unevaluatedProperties" property instead of "additionalProperties" one in the DT schema. - Due to the previous fix we can now discard the dummy boolean properties declaration, since the proper type evaluation will be performed by the generic i2c-controller.yaml schema. - Refactor the DW I2C APB driver related series to address the Andies notes. - Convert DW APB I2C driver to using regmap instead of handwritten accessors. - Use `-y` to build multi-object DW APB drivers. - Fix DW APB I2C slave code dependency. It should depend on I2C_DESIGNWARE_CORE instead I2C_DESIGNWARE_PLATFORM. - Move Baytrail semaphore config to the platform if-clause. - Introduce a glue-layer platform driver API. - Unpin Microsemi Ocelot I2C code into a glue driver. - Remove MODEL_CHERRYTRAIL and MODEL_MASK as no longer needed. - Add support for custom regmap passed from glue driver. - Add Baikal-T1 System I2C support in a dedicated glue layer driver. Serge Semin (12): scripts/dtc: check: Add 10bit/slave i2c reg flags support dt-bindings: i2c: Convert DW I2C binding to DT schema dt-bindings: i2c: dw: Add Baikal-T1 SoC I2C controller i2c: designware: Convert driver to using regmap API i2c: designware: Use `-y` to build multi-object modules i2c: designware: slave: Set DW I2C core module dependency i2c: designware: Move Baytrail sem config to the platform if-clause i2c: designware: Introduce platform drivers glue layer interface i2c: designware: Unpin Microsemi Ocelot I2C into a glue driver i2c: designware: Discard Cherry Trail model flag i2c: designware: Use provided regmap instead of reg resource i2c: designware: Add Baikal-T1 System I2C glue driver .../bindings/i2c/i2c-designware.txt | 73 ------- .../bindings/i2c/snps,designware-i2c.yaml | 164 ++++++++++++++++ drivers/i2c/busses/Kconfig | 56 ++++-- drivers/i2c/busses/Makefile | 19 +- drivers/i2c/busses/i2c-designware-bt1.c | 129 +++++++++++++ drivers/i2c/busses/i2c-designware-common.c | 178 +++++++++++++----- drivers/i2c/busses/i2c-designware-core.h | 26 ++- drivers/i2c/busses/i2c-designware-master.c | 125 ++++++------ drivers/i2c/busses/i2c-designware-mscc.c | 83 ++++++++ drivers/i2c/busses/i2c-designware-pcidrv.c | 1 - drivers/i2c/busses/i2c-designware-platdrv.c | 132 ++++++------- drivers/i2c/busses/i2c-designware-platdrv.h | 16 ++ drivers/i2c/busses/i2c-designware-slave.c | 77 ++++---- scripts/dtc/checks.c | 13 +- 14 files changed, 759 insertions(+), 333 deletions(-) delete mode 100644 Documentation/devicetree/bindings/i2c/i2c-designware.txt create mode 100644 Documentation/devicetree/bindings/i2c/snps,designware-i2c.yaml create mode 100644 drivers/i2c/busses/i2c-designware-bt1.c create mode 100644 drivers/i2c/busses/i2c-designware-mscc.c create mode 100644 drivers/i2c/busses/i2c-designware-platdrv.h