From patchwork Sat Dec 4 19:57:52 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Sam Protsenko X-Patchwork-Id: 520735 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 627FEC433FE for ; Sat, 4 Dec 2021 19:58:04 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1351074AbhLDUB1 (ORCPT ); Sat, 4 Dec 2021 15:01:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49400 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344972AbhLDUB1 (ORCPT ); Sat, 4 Dec 2021 15:01:27 -0500 Received: from mail-wr1-x42f.google.com (mail-wr1-x42f.google.com [IPv6:2a00:1450:4864:20::42f]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0EB08C061751 for ; Sat, 4 Dec 2021 11:58:01 -0800 (PST) Received: by mail-wr1-x42f.google.com with SMTP id q3so13305726wru.5 for ; Sat, 04 Dec 2021 11:58:00 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=5Tae7shI/erDBK4JbFqL57PR9dNyL7JXb+7DeAlnpbE=; b=HYbAMkZQ7OyhNh+oJ+o26au8HLeEYXjmkei/adv8/PCYcWI3IKBVgGPM3+yw6nJ9tq y88Kv2DVc2HfYedBiSmrcsS5KhwHV04zoFQpgf/zhB7jewv63yH4O7cXMViNRPyyU3HM +gWQNlDfAWwyBFvoPVsHKRhirK9leTz7pKic/sHhCuLVsIHkmraUl+6AEdCPvybPxylm 872i28hbddCHq/BTH+RahXxsA6k2muhrWaze1KjveMtx7M4TGLI2nSQvoj0qQVfQbw62 nb8l+UgNLjjUav+pqqccAGAlKAxeDmhDauEf4lE3zzMWe9kBnnsF4bwlxCUs58E6Ub/N 4a3Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=5Tae7shI/erDBK4JbFqL57PR9dNyL7JXb+7DeAlnpbE=; b=GhN9VICsD6hGuRNTiENskfP3DyIrBmxv6C3QjsBNKfd/B6o7U2NzXGWg7Uas5BOpYB JXI+Nln+wGh4yIZmJWuwpU5bFsRGhGfptGNvpSFhprf5TrVPFF/MLT9ROUztkoZJeOLU 6kGkF7//cr2scH/NnrVrM5Hg8ZFxkABqi1g3rtOXiSSQc8t1eifWVLBoRWGlHCn1IYFc 2U2bc3Qf1gdN7AV1qYLL8DEu3ORpUllTm7cZGm8vgiA+oTogDC43W8zuoViw0FJAH5Nh 98OTNrVYsZmT7WWIOavrRSYngO/WFU2T6EAtEDYNffUVzdR84e8HPtboD45co5cSL9gr OFhQ== X-Gm-Message-State: AOAM530jMfwF50ypg0A+d1417dE44/Pq3GQjHK30QIIJ4K7pJYlDT6TV MSO4KJ9j/9bmr8Zl/LMnALXnpg== X-Google-Smtp-Source: ABdhPJxwjIqYxZ/dHI2yVxue6xSU9HkKtY/F4RcR68UF2cflsf4OPRwRK95eY5hT0ZZNFe3+ydy2ng== X-Received: by 2002:a5d:404d:: with SMTP id w13mr30057082wrp.293.1638647879454; Sat, 04 Dec 2021 11:57:59 -0800 (PST) Received: from localhost ([31.134.121.151]) by smtp.gmail.com with ESMTPSA id m14sm9185932wrp.28.2021.12.04.11.57.58 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sat, 04 Dec 2021 11:57:58 -0800 (PST) From: Sam Protsenko To: Krzysztof Kozlowski , Rob Herring , Greg Kroah-Hartman Cc: Jaewon Kim , Chanho Park , David Virag , Youngmin Nam , devicetree@vger.kernel.org, linux-serial@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-samsung-soc@vger.kernel.org Subject: [PATCH v3 0/5] soc: samsung: Add USI driver Date: Sat, 4 Dec 2021 21:57:52 +0200 Message-Id: <20211204195757.8600-1-semen.protsenko@linaro.org> X-Mailer: git-send-email 2.30.2 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-samsung-soc@vger.kernel.org USIv2 IP-core provides selectable serial protocol (UART, SPI or High-Speed I2C); only one can be chosen at a time. This series implements USIv2 driver, which allows one to select particular USI function in device tree, and also performs USI block initialization. With that driver implemented, it's not needed to do USI initialization in protocol drivers anymore, so that code is removed from the serial driver. Because USI driver is tristate (can be built as a module), serial driver was reworked so it's possible to use its console part as a module too. This way we can load serial driver module from user space and still have serial console functional. Design features: - "reg" property contains USI registers start address (0xc0 offset); it's used in the driver to access USI_CON and USI_OPTION registers. This way all USI initialization (reset, HWACG, etc) can be done in USIv2 driver separately, rather than duplicating that code over UART/SPI/I2C drivers - System Register (system controller node) and its SW_CONF register offset are provided in "samsung,sysreg" property; it's used to select USI function (protocol to be used) - USI function is specified in "samsung,mode" property; integer value is used to simplify parsing - there is "samsung,clkreq-on" bool property, which makes driver disable HWACG control (needed for UART to work properly) - PCLK and IPCLK clocks are both provided to USI node; apparently both need to be enabled to access USI registers - protocol nodes are embedded (as a child nodes) in USI node; it allows correct init order, and reflects HW properly - USI driver is a tristate: can be also useful from Android GKI requirements point of view - driver functions are implemented with further development in mind: - we might want to add some DebugFs interface later - some functions might need to be revealed to serial drivers with EXPORT_SYMBOL(), and provide somehow pointer to needed USI driver instance - another USI revisions could be added (like USIv1) Changes in v3: - Renamed compatible from samsung,exynos-usi-v2 to samsung,exynos850-usi - Used clk_bulk API instead of handling each clock separately - Spell check fixes and coding style fixes - Improved dt-bindings doc Changes in v2: - Renamed all 'usi_v2' wording to just 'usi' everywhere - Removed patches adding dependency on EXYNOS_USI for UART/I2C/SPI drivers - Added patch: "tty: serial: samsung: Fix console registration from module" - Combined dt-bindings doc and dt-bindings header patches - Reworked USI driver to be ready for USIv1 addition - Improved dt-bindings - Added USI_V2_NONE mode value Sam Protsenko (5): dt-bindings: soc: samsung: Add Exynos USI bindings soc: samsung: Add USI driver tty: serial: samsung: Remove USI initialization tty: serial: samsung: Enable console as module tty: serial: samsung: Fix console registration from module .../bindings/soc/samsung/exynos-usi.yaml | 159 ++++++++++ drivers/soc/samsung/Kconfig | 14 + drivers/soc/samsung/Makefile | 2 + drivers/soc/samsung/exynos-usi.c | 285 ++++++++++++++++++ drivers/tty/serial/Kconfig | 2 +- drivers/tty/serial/samsung_tty.c | 78 ++--- include/dt-bindings/soc/samsung,exynos-usi.h | 17 ++ include/linux/serial_s3c.h | 9 - 8 files changed, 518 insertions(+), 48 deletions(-) create mode 100644 Documentation/devicetree/bindings/soc/samsung/exynos-usi.yaml create mode 100644 drivers/soc/samsung/exynos-usi.c create mode 100644 include/dt-bindings/soc/samsung,exynos-usi.h