From patchwork Wed Jul 27 14:24:04 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Caesar Wang X-Patchwork-Id: 9249887 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 4EBD160757 for ; Wed, 27 Jul 2016 14:26:26 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3E24925223 for ; Wed, 27 Jul 2016 14:26:26 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 320F126D08; Wed, 27 Jul 2016 14:26:26 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-4.2 required=2.0 tests=BAYES_00, RCVD_IN_DNSWL_MED autolearn=unavailable version=3.3.1 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.9]) (using TLSv1.2 with cipher AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id A8EC325223 for ; Wed, 27 Jul 2016 14:26:25 +0000 (UTC) Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.85_2 #1 (Red Hat Linux)) id 1bSPlM-0002gj-0Z; Wed, 27 Jul 2016 14:24:44 +0000 Received: from mail-pa0-f68.google.com ([209.85.220.68]) by bombadil.infradead.org with esmtps (Exim 4.85_2 #1 (Red Hat Linux)) id 1bSPlI-0002dc-Hg; Wed, 27 Jul 2016 14:24:41 +0000 Received: by mail-pa0-f68.google.com with SMTP id q2so1859356pap.0; Wed, 27 Jul 2016 07:24:20 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:from:to:cc:subject:date:message-id; bh=5uKI81r+7apL65JE8n+1ZLksfvjbcgxnAwq7CosHo/o=; b=c27Bat+rfBj23qiV1xR/ZWDy5ENjSPRry1YKcpf/bDKZBEv40nysiMPMLmkDWw7pf+ //RGTuniG/El2izGb7rXjLVH1ji/QYv3lZKbEK4cF/1AFTrN7D/0ph6xpsgpYocpVdUz TBkW84tHasU5SEGApwTPjaxSFvXcEeNbEKkYByZn3Ah30OAAjNd2saJjFtBe74MJCOWP gL14yNDNI061l/x1hHbATYtUxcelXSBhf3iuhIWkjHqEHAfi3qp7nTsj+rBPHF+Iu8n/ tv9EA9Acg7uzPi/XFhxfnYYXom0eVcznRi7l4YeDAtwJQrWEwqBXFbiIpgSS63/yMzEe dGcA== X-Gm-Message-State: AEkoouvWzd4wBUVY6q49KB3CgLMz7EiEg4y3Qru9QJdaPF6DSpHOde6dWO8VOczuQ/8UDA== X-Received: by 10.66.43.234 with SMTP id z10mr49756373pal.137.1469629459942; Wed, 27 Jul 2016 07:24:19 -0700 (PDT) Received: from localhost.localdomain ([103.29.142.67]) by smtp.gmail.com with ESMTPSA id yv9sm9884892pab.0.2016.07.27.07.24.16 (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Wed, 27 Jul 2016 07:24:19 -0700 (PDT) From: Caesar Wang To: jic23@kernel.org, heiko@sntech.de Subject: [PATCH v3 1/4] iio: adc: rockchip_saradc: reset saradc controller before programming it Date: Wed, 27 Jul 2016 22:24:04 +0800 Message-Id: <1469629447-544-1-git-send-email-wxt@rock-chips.com> X-Mailer: git-send-email 1.9.1 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20160727_072440_615981_9242D51C X-CRM114-Status: GOOD ( 15.90 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: devicetree@vger.kernel.org, linux-iio@vger.kernel.org, linux-kernel@vger.kernel.org, dianders@chromium.org, linux-rockchip@lists.infradead.org, robh+dt@kernel.org, john@metanate.com, linux-arm-kernel@lists.infradead.org, linux@roeck-us.net, Caesar Wang MIME-Version: 1.0 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.kernel.org@lists.infradead.org X-Virus-Scanned: ClamAV using ClamSMTP SARADC controller needs to be reset before programming it, otherwise it will not function properly. Signed-off-by: Caesar Wang Cc: Jonathan Cameron Cc: Heiko Stuebner Cc: Rob Herring Cc: linux-iio@vger.kernel.org Cc: linux-rockchip@lists.infradead.org Tested-by: Guenter Roeck Reviewed-by: Guenter Roeck Acked-by: Rob Herring Acked-by: Rob Herring Acked-by: Jonathan Cameron --- Changes in v3: - %s/devm_reset_control_get_optional()/devm_reset_control_get() - add Guente's test tag. Changes in v2: - Make the reset as an optional property, since it should work with old devicetrees as well. .../bindings/iio/adc/rockchip-saradc.txt | 7 +++++ drivers/iio/adc/Kconfig | 1 + drivers/iio/adc/rockchip_saradc.c | 30 ++++++++++++++++++++++ 3 files changed, 38 insertions(+) diff --git a/Documentation/devicetree/bindings/iio/adc/rockchip-saradc.txt b/Documentation/devicetree/bindings/iio/adc/rockchip-saradc.txt index bf99e2f..205593f 100644 --- a/Documentation/devicetree/bindings/iio/adc/rockchip-saradc.txt +++ b/Documentation/devicetree/bindings/iio/adc/rockchip-saradc.txt @@ -16,6 +16,11 @@ Required properties: - vref-supply: The regulator supply ADC reference voltage. - #io-channel-cells: Should be 1, see ../iio-bindings.txt +Optional properties: +- resets: Must contain an entry for each entry in reset-names if need support + this option. See ../reset/reset.txt for details. +- reset-names: Must include the name "saradc-apb". + Example: saradc: saradc@2006c000 { compatible = "rockchip,saradc"; @@ -23,6 +28,8 @@ Example: interrupts = ; clocks = <&cru SCLK_SARADC>, <&cru PCLK_SARADC>; clock-names = "saradc", "apb_pclk"; + resets = <&cru SRST_SARADC>; + reset-names = "saradc-apb"; #io-channel-cells = <1>; vref-supply = <&vcc18>; }; diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig index 1de31bd..7675772 100644 --- a/drivers/iio/adc/Kconfig +++ b/drivers/iio/adc/Kconfig @@ -389,6 +389,7 @@ config QCOM_SPMI_VADC config ROCKCHIP_SARADC tristate "Rockchip SARADC driver" depends on ARCH_ROCKCHIP || (ARM && COMPILE_TEST) + depends on RESET_CONTROLLER help Say yes here to build support for the SARADC found in SoCs from Rockchip. diff --git a/drivers/iio/adc/rockchip_saradc.c b/drivers/iio/adc/rockchip_saradc.c index f9ad6c2..85d7012 100644 --- a/drivers/iio/adc/rockchip_saradc.c +++ b/drivers/iio/adc/rockchip_saradc.c @@ -21,6 +21,8 @@ #include #include #include +#include +#include #include #include @@ -53,6 +55,7 @@ struct rockchip_saradc { struct clk *clk; struct completion completion; struct regulator *vref; + struct reset_control *reset; const struct rockchip_saradc_data *data; u16 last_val; }; @@ -190,6 +193,16 @@ static const struct of_device_id rockchip_saradc_match[] = { }; MODULE_DEVICE_TABLE(of, rockchip_saradc_match); +/** + * Reset SARADC Controller. + */ +static void rockchip_saradc_reset_controller(struct reset_control *reset) +{ + reset_control_assert(reset); + usleep_range(10, 20); + reset_control_deassert(reset); +} + static int rockchip_saradc_probe(struct platform_device *pdev) { struct rockchip_saradc *info = NULL; @@ -218,6 +231,20 @@ static int rockchip_saradc_probe(struct platform_device *pdev) if (IS_ERR(info->regs)) return PTR_ERR(info->regs); + /* + * The reset should be an optional property, as it should work + * with old devicetrees as well + */ + info->reset = devm_reset_control_get(&pdev->dev, "saradc-apb"); + if (IS_ERR(info->reset)) { + ret = PTR_ERR(info->reset); + if (ret != -ENOENT) + return ret; + + dev_dbg(&pdev->dev, "no reset control found\n"); + info->reset = NULL; + } + init_completion(&info->completion); irq = platform_get_irq(pdev, 0); @@ -252,6 +279,9 @@ static int rockchip_saradc_probe(struct platform_device *pdev) return PTR_ERR(info->vref); } + if (info->reset) + rockchip_saradc_reset_controller(info->reset); + /* * Use a default value for the converter clock. * This may become user-configurable in the future.