From patchwork Mon Aug 26 15:42:52 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dinh Nguyen X-Patchwork-Id: 11114963 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 941E91800 for ; Mon, 26 Aug 2019 15:45:12 +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 718CE20874 for ; Mon, 26 Aug 2019 15:45:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="sNYxYOW7"; dkim=fail reason="signature verification failed" (1024-bit key) header.d=kernel.org header.i=@kernel.org header.b="IZJ1OOsq" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 718CE20874 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+patchwork-linux-arm=patchwork.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=jpzcqIl8+2f/XsatsmyV2WwkhQ4IXckIIyK8o6LOZis=; b=sNYxYOW7f8pXiI XBl78/QiX+dNcFKFDNKDZYpwxU/p9gcx8Kig81nS+c8JJlpgmCTvsXTBtLYe4nIhV2xsLiOJoT9T+ 5QSZsJEuwJ6R7uB0yv19I5aR68fhTgJzubxlmiNKQo3YTAKfhPw09OzyDiL6yY67YL0W3v/bTq2c5 GTyIDzG0xmQab1xB1lJvefWlO7cgjLjLF1U+hd41BZkId2dlkydw0DNkpw3KE8bZJDdd5ugkEtYoy UL9EZGo1gehXtSnf57ktBPiTbc60xNQwQWLL/W+o+cnFTUr54ZeQDbGjC0savTbUH/RGvFX1WxR+u /p+4jqMcEkA/twss3WXg==; 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 1i2HB7-00006E-Ts; Mon, 26 Aug 2019 15:45:10 +0000 Received: from mail.kernel.org ([198.145.29.99]) by bombadil.infradead.org with esmtps (Exim 4.92 #3 (Red Hat Linux)) id 1i2H98-0007eQ-DK for linux-arm-kernel@lists.infradead.org; Mon, 26 Aug 2019 15:43:08 +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 A973520874; Mon, 26 Aug 2019 15:43:04 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1566834185; bh=IrvkLc5Ov+J/f8CttzyyWurWNwwmFftVjPaVQ+/Erqs=; h=From:To:Cc:Subject:Date:From; b=IZJ1OOsq+OVzE855bSAuMug6lB/iT8i5Ri6k3jzoxm0k9fjMH806zFUSijzubbxKx LWomNqyfpbzl/CajzHjJWwaZq1q2RieGA+rpC7ChH9xgyUAyuEAZKLEWq+Jmq/KAuC Hb1Pf9685vzxvdY3JJR7i48sLMFOfRvQBREZpqjU= From: Dinh Nguyen To: linux-kernel@vger.kernel.org Subject: [PATCHv5] drivers/amba: add reset control to amba bus probe Date: Mon, 26 Aug 2019 10:42:52 -0500 Message-Id: <20190826154252.22952-1-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-20190826_084306_528401_F53453C9 X-CRM114-Status: GOOD ( 15.22 ) X-Spam-Score: -5.2 (-----) X-Spam-Report: SpamAssassin version 3.4.2 on bombadil.infradead.org summary: Content analysis details: (-5.2 points) pts rule name description ---- ---------------------- -------------------------------------------------- -5.0 RCVD_IN_DNSWL_HI RBL: Sender listed at https://www.dnswl.org/, high trust [198.145.29.99 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 SPF_HELO_NONE SPF: HELO does not publish an SPF Record -0.1 DKIM_VALID Message has at least one valid DKIM or DK signature 0.1 DKIM_SIGNED Message has a DKIM or DK signature, not necessarily valid -0.1 DKIM_VALID_AU Message has a valid DKIM or DK signature from author's domain -0.1 DKIM_VALID_EF Message has a valid DKIM or DK signature from envelope-from domain -0.0 DKIMWL_WL_HIGH DKIMwl.org - Whitelisted High sender 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 Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+patchwork-linux-arm=patchwork.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 --- 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 | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) diff --git a/drivers/amba/bus.c b/drivers/amba/bus.c index 100e798a5c82..f8a7cb74c3cf 100644 --- a/drivers/amba/bus.c +++ b/drivers/amba/bus.c @@ -18,6 +18,7 @@ #include #include #include +#include #include @@ -401,6 +402,24 @@ 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; + int count; + struct reset_control *rstc; + + /* + * Find reset control(s) of the amba bus and de-assert them. + */ + count = reset_control_get_count(&dev->dev); + while (count > 0) { + 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); + count--; + } /* * Read pid and cid based on size of resource