From patchwork Tue Oct 18 01:45:09 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Shawn Lin X-Patchwork-Id: 9381007 X-Patchwork-Delegate: bhelgaas@google.com 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 3C8AE60487 for ; Tue, 18 Oct 2016 01:39:58 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 3107D28CBC for ; Tue, 18 Oct 2016 01:39:58 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 25D0C291A0; Tue, 18 Oct 2016 01:39:58 +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=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id CD80028CBC for ; Tue, 18 Oct 2016 01:39:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757006AbcJRBj4 (ORCPT ); Mon, 17 Oct 2016 21:39:56 -0400 Received: from lucky1.263xmail.com ([211.157.147.131]:49652 "EHLO lucky1.263xmail.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756564AbcJRBj1 (ORCPT ); Mon, 17 Oct 2016 21:39:27 -0400 Received: from shawn.lin?rock-chips.com (unknown [192.168.167.87]) by lucky1.263xmail.com (Postfix) with ESMTP id 667378ED45; Tue, 18 Oct 2016 09:39:23 +0800 (CST) X-263anti-spam: KSV:0; X-MAIL-GRAY: 1 X-MAIL-DELIVERY: 0 X-KSVirus-check: 0 X-ABS-CHECKED: 4 X-ADDR-CHECKED4: 1 Received: from localhost.localdomain (localhost [127.0.0.1]) by smtp.263.net (Postfix) with ESMTP id BB7B23B9; Tue, 18 Oct 2016 09:39:20 +0800 (CST) X-RL-SENDER: shawn.lin@rock-chips.com X-FST-TO: bhelgaas@google.com X-SENDER-IP: 58.22.7.114 X-LOGIN-NAME: shawn.lin@rock-chips.com X-UNIQUE-TAG: <55bd730cad6055cee8155e8c71e65b90> X-ATTACHMENT-NUM: 0 X-SENDER: lintao@rock-chips.com X-DNS-TYPE: 0 Received: from unknown (unknown [58.22.7.114]) by smtp.263.net (Postfix) whith SMTP id 738839GRZD; Tue, 18 Oct 2016 09:39:22 +0800 (CST) From: Shawn Lin To: Bjorn Helgaas , Rob Herring Cc: linux-pci@vger.kernel.org, linux-rockchip@lists.infradead.org, Wenrui Li , Brian Norris , devicetree@vger.kernel.org, Shawn Lin Subject: [PATCH v8 2/3] of/pci: Add helper function to parse max-link-speed from dt Date: Tue, 18 Oct 2016 09:45:09 +0800 Message-Id: <1476755110-22647-2-git-send-email-shawn.lin@rock-chips.com> X-Mailer: git-send-email 1.8.0 In-Reply-To: <1476755110-22647-1-git-send-email-shawn.lin@rock-chips.com> References: <1476755110-22647-1-git-send-email-shawn.lin@rock-chips.com> Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP This new helper function could be used by host drivers to get the limitaion of max link speed provided by dt. If the property isn't assigned or is invalid, it will return -EINVAL to the caller. Signed-off-by: Shawn Lin Acked-by: Rob Herring --- Changes in v8: None Changes in v7: - rename the function name and using of_property_read_u32 suggested by Rob Changes in v6: None Changes in v5: None Changes in v4: None Changes in v3: None Changes in v2: None drivers/of/of_pci.c | 21 +++++++++++++++++++++ include/linux/of_pci.h | 7 +++++++ 2 files changed, 28 insertions(+) diff --git a/drivers/of/of_pci.c b/drivers/of/of_pci.c index 589b30c..0c566ca 100644 --- a/drivers/of/of_pci.c +++ b/drivers/of/of_pci.c @@ -120,6 +120,27 @@ int of_get_pci_domain_nr(struct device_node *node) EXPORT_SYMBOL_GPL(of_get_pci_domain_nr); /** + * This function will try to find the limitation of link speed by finding + * a property called "max-link-speed" of the given device node. + * + * @node: device tree node with the max link speed information + * + * Returns the associated max link speed from DT, or a negative value if the + * required property is not found or is invalid. + */ +int of_pci_get_max_link_speed(struct device_node *node) +{ + u32 max_link_speed; + + if (of_property_read_u32(node, "max-link-speed", &max_link_speed) || + max_link_speed > 4) + return -EINVAL; + + return max_link_speed; +} +EXPORT_SYMBOL_GPL(of_pci_get_max_link_speed); + +/** * of_pci_check_probe_only - Setup probe only mode if linux,pci-probe-only * is present and valid */ diff --git a/include/linux/of_pci.h b/include/linux/of_pci.h index b969e94..2e668e3 100644 --- a/include/linux/of_pci.h +++ b/include/linux/of_pci.h @@ -16,6 +16,7 @@ int of_pci_get_devfn(struct device_node *np); int of_irq_parse_and_map_pci(const struct pci_dev *dev, u8 slot, u8 pin); int of_pci_parse_bus_range(struct device_node *node, struct resource *res); int of_get_pci_domain_nr(struct device_node *node); +int of_pci_get_max_link_speed(struct device_node *node); void of_pci_check_probe_only(void); #else static inline int of_irq_parse_pci(const struct pci_dev *pdev, struct of_phandle_args *out_irq) @@ -52,6 +53,12 @@ of_get_pci_domain_nr(struct device_node *node) return -1; } +static inline int +of_pci_get_max_link_speed(struct device_node *node) +{ + return -EINVAL; +} + static inline void of_pci_check_probe_only(void) { } #endif