From patchwork Fri Mar 23 14:24:34 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mike Looijmans X-Patchwork-Id: 890000 Return-Path: X-Original-To: incoming-dt@patchwork.ozlabs.org Delivered-To: patchwork-incoming-dt@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=devicetree-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=none (p=none dis=none) header.from=topic.nl Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 4075Qk0kYzz9s0w for ; Sat, 24 Mar 2018 01:24:46 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751658AbeCWOYo (ORCPT ); Fri, 23 Mar 2018 10:24:44 -0400 Received: from atl4mhob13.registeredsite.com ([209.17.115.51]:47496 "EHLO atl4mhob13.registeredsite.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751541AbeCWOYn (ORCPT ); Fri, 23 Mar 2018 10:24:43 -0400 Received: from mailpod.hostingplatform.com (atl4qobmail02.registeredsite.com [10.30.71.204]) by atl4mhob13.registeredsite.com (8.14.4/8.14.4) with ESMTP id w2NEOdLh013755 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-GCM-SHA384 bits=256 verify=FAIL) for ; Fri, 23 Mar 2018 10:24:39 -0400 Received: (qmail 1310 invoked by uid 0); 23 Mar 2018 14:24:39 -0000 X-TCPREMOTEIP: 37.74.225.130 X-Authenticated-UID: mike@milosoftware.com Received: from unknown (HELO mikebuntu.TOPIC.LOCAL) (mike@milosoftware.com@37.74.225.130) by 0 with ESMTPA; 23 Mar 2018 14:24:38 -0000 From: Mike Looijmans To: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org, devicetree@vger.kernel.org, andrew@lunn.ch, f.fainelli@gmail.com, robh+dt@kernel.org, frowand.list@gmail.com, Mike Looijmans Subject: [PATCH] of_net: Implement of_get_nvmem_mac_address helper Date: Fri, 23 Mar 2018 15:24:34 +0100 Message-Id: <1521815074-30424-1-git-send-email-mike.looijmans@topic.nl> X-Mailer: git-send-email 1.9.1 Sender: devicetree-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: devicetree@vger.kernel.org It's common practice to store MAC addresses for network interfaces into nvmem devices. However the code to actually do this in the kernel lacks, so this patch adds of_get_nvmem_mac_address() for drivers to obtain the address from an nvmem cell provider. This is particulary useful on devices where the ethernet interface cannot be configured by the bootloader, for example because it's in an FPGA. Tested by adapting the cadence macb driver to call this instead of of_get_mac_address(). Signed-off-by: Mike Looijmans --- drivers/of/of_net.c | 48 ++++++++++++++++++++++++++++++++++++++++++++++++ include/linux/of_net.h | 6 ++++++ 2 files changed, 54 insertions(+) diff --git a/drivers/of/of_net.c b/drivers/of/of_net.c index d820f3e..316a537 100644 --- a/drivers/of/of_net.c +++ b/drivers/of/of_net.c @@ -7,6 +7,7 @@ */ #include #include +#include #include #include #include @@ -80,3 +81,50 @@ const void *of_get_mac_address(struct device_node *np) return of_get_mac_addr(np, "address"); } EXPORT_SYMBOL(of_get_mac_address); + +/** + * Search the device tree for a MAC address, by calling of_get_mac_address + * and if that doesn't provide an address, fetch it from an nvmem provider + * using the name 'mac-address'. + * On success, copies the new address is into memory pointed to by addr and + * returns 0. Returns a negative error code otherwise. + * @dev: Pointer to the device containing the device_node + * @addr: Pointer to receive the MAC address using ether_addr_copy() + */ +int of_get_nvmem_mac_address(struct device *dev, char *addr) +{ + const char *mac; + struct nvmem_cell *cell; + size_t len; + int ret; + + mac = of_get_mac_address(dev->of_node); + if (mac) { + ether_addr_copy(addr, mac); + return 0; + } + + cell = nvmem_cell_get(dev, "mac-address"); + if (IS_ERR(cell)) + return PTR_ERR(cell); + + mac = (const char *)nvmem_cell_read(cell, &len); + + nvmem_cell_put(cell); + + if (IS_ERR(mac)) + return PTR_ERR(mac); + + if (len < 6 || !is_valid_ether_addr(mac)) { + dev_err(dev, "MAC address from NVMEM is invalid\n"); + ret = -EINVAL; + } else { + ether_addr_copy(addr, mac); + ret = 0; + } + + kfree(mac); + + return ret; +} +EXPORT_SYMBOL(of_get_nvmem_mac_address); diff --git a/include/linux/of_net.h b/include/linux/of_net.h index 9cd72aa..0d52e1d 100644 --- a/include/linux/of_net.h +++ b/include/linux/of_net.h @@ -13,6 +13,7 @@ struct net_device; extern int of_get_phy_mode(struct device_node *np); extern const void *of_get_mac_address(struct device_node *np); +extern int of_get_nvmem_mac_address(struct device *dev, char *addr); extern struct net_device *of_find_net_device_by_node(struct device_node *np); #else static inline int of_get_phy_mode(struct device_node *np) @@ -25,6 +26,11 @@ static inline const void *of_get_mac_address(struct device_node *np) return NULL; } +static inline int of_get_nvmem_mac_address(struct device *dev, char *addr) +{ + return -ENODEV; +} + static inline struct net_device *of_find_net_device_by_node(struct device_node *np) { return NULL;