From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-10.0 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE, SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 8CF79C3A5A3 for ; Tue, 27 Aug 2019 14:13:42 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 5F79B214DA for ; Tue, 27 Aug 2019 14:13:42 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="GDV0R5ok"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="NBcLeWKj" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 5F79B214DA Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:MIME-Version:Message-Id:Date:Subject:To :From:Reply-To:Content-ID:Content-Description:Resent-Date:Resent-From: Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID:In-Reply-To:References: List-Owner; bh=oq2AZPUXraiUDc6Mac70oUtNXnszzcHPRtI4HSNJbhM=; b=GDV0R5ok7LAub2 3zkLWVWHfcKqXWBTKi/GeyM2N7uVRSXhLBI8YW1deDabENhHlWOBFPyI8Mk6EhGPJSkiumJS1/ytP 9/Z5FxAMajy1bX3IRvmmdzd6wWug73TWCIHhQ7rQkEo9sMKerHoCFiyiHEca16naHwiEMdQLJjrVj vvJdKgrgGoFnyb6g0WsUyOgl5IS/EetyjBWOx1/DBKSyaE7iEIOPHmSgJNqnpA4j8XzYi4VQeLRnk 4Izo53PVX3pmUhxxeTJCWNX16KkzxtBQ3XnnFs/pDZiGDjm+aPDsHWmcSvQ1APWJl4NhlQB7aQCc1 VrttT8rkyHpxr8KS49tQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92 #3 (Red Hat Linux)) id 1i2cDz-0007wR-Ku; Tue, 27 Aug 2019 14:13:31 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92 #3 (Red Hat Linux)) id 1i2cDw-0007vi-SM for linux-arm-kernel@lists.infradead.org; Tue, 27 Aug 2019 14:13:30 +0000 Received: from localhost.localdomain (cpe-70-114-128-244.austin.res.rr.com [70.114.128.244]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 4CB52214DA; Tue, 27 Aug 2019 14:13:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566915208; bh=pl2trC3SUKLOMkiq8cJFVya7N1BiXPCf1NJhGvJLSMw=; h=From:To:Cc:Subject:Date:From; b=NBcLeWKjodp6DLvUNoe/GG4H9KDx7NsTp+DJ7tH/ydWrFedw9eck+AcxxEJbK+nDk uEikpV6cGeBlB14TQPMBjzRXXPL1ki0eVbmOTI9WmOyFlsMkkN/C6O5dfciw4m7/qw vVhaq7mVFhCnlTK277nOfy12FBpandzq+VL1mXY8= From: Dinh Nguyen To: linux-kernel@vger.kernel.org Subject: [PATCHv6] drivers/amba: add reset control to amba bus probe Date: Tue, 27 Aug 2019 09:11:53 -0500 Message-Id: <20190827141153.20254-1-dinguyen@kernel.org> X-Mailer: git-send-email 2.20.0 MIME-Version: 1.0 X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20190827_071328_938763_1B3C1F46 X-CRM114-Status: GOOD ( 14.81 ) X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: robh@kernel.org, daniel.thompson@linaro.org, tony.luck@intel.com, manivannan.sadhasivam@linaro.org, keescook@chromium.org, devicetree@vger.kernel.org, linus.walleij@linaro.org, anton@enomsg.org, linux@armlinux.org.uk, dinguyen@kernel.org, p.zabel@pengutronix.de, ccross@android.com, frowand.list@gmail.com, linux-arm-kernel@lists.infradead.org Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+infradead-linux-arm-kernel=archiver.kernel.org@lists.infradead.org The primecell controller on some SoCs, i.e. SoCFPGA, is held in reset by default. Until recently, the DMA controller was brought out of reset by the bootloader(i.e. U-Boot). But a recent change in U-Boot, the peripherals that are not used are held in reset and are left to Linux to bring them out of reset. Add a mechanism for getting the reset property and de-assert the primecell module from reset if found. This is a not a hard fail if the reset properti is not present in the device tree node, so the driver will continue to probe. Because there are different variants of the controller that may have multiple reset signals, the code will find all reset(s) specified and de-assert them. Signed-off-by: Dinh Nguyen Reviewed-by: Rob Herring --- v6: remove the need to reset_control_get_count as of_reset_control_array_get_optional_shared is already doing that v5: use of_reset_control_array_get_optional_shared() v4: cleaned up indentation in loop fix up a few checkpatch warnings add Reviewed-by: v3: add a reset_control_put() add error handling v2: move reset control to bus code find all reset properties and de-assert them --- drivers/amba/bus.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+) diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c index 100e798a5c82..f39f075abff9 100644 --- a/drivers/amba/bus.c +++ b/drivers/amba/bus.c @@ -18,6 +18,7 @@ #include #include #include +#include #include @@ -401,6 +402,19 @@ static int amba_device_try_add(struct amba_device *dev, struct resource *parent) ret = amba_get_enable_pclk(dev); if (ret == 0) { u32 pid, cid; + struct reset_control *rstc; + + /* + * Find reset control(s) of the amba bus and de-assert them. + */ + rstc = of_reset_control_array_get_optional_shared(dev->dev.of_node); + if (IS_ERR(rstc)) { + if (PTR_ERR(rstc) != -EPROBE_DEFER) + dev_err(&dev->dev, "Can't get amba reset!\n"); + return PTR_ERR(rstc); + } + reset_control_deassert(rstc); + reset_control_put(rstc); /* * Read pid and cid based on size of resource -- 2.20.0 _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel