From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935622AbcCQK0e (ORCPT ); Thu, 17 Mar 2016 06:26:34 -0400 Received: from mail-wm0-f42.google.com ([74.125.82.42]:33082 "EHLO mail-wm0-f42.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935501AbcCQK0b (ORCPT ); Thu, 17 Mar 2016 06:26:31 -0400 Subject: Re: [PATCH] ARM: davinci: only use NVMEM when available To: Arnd Bergmann , Greg Kroah-Hartman References: <1458077705-408437-1-git-send-email-arnd@arndb.de> Cc: Sekhar Nori , Kevin Hilman , Andrew Lunn , Wolfram Sang , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org From: Srinivas Kandagatla Message-ID: <56EA8654.5070100@linaro.org> Date: Thu, 17 Mar 2016 10:26:28 +0000 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:38.0) Gecko/20100101 Thunderbird/38.6.0 MIME-Version: 1.0 In-Reply-To: <1458077705-408437-1-git-send-email-arnd@arndb.de> Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Thanks for the patch, On 15/03/16 21:34, Arnd Bergmann wrote: > The davinci platform contains code that calls into the nvmem > subsystem, but that might be a loadable module, causing a > link error: > > arch/arm/mach-davinci/built-in.o: In function `davinci_get_mac_addr': > :(.text+0x1088): undefined reference to `nvmem_device_read' > arch/arm/mach-davinci/built-in.o: In function `read_factory_config': > :(.text+0x214c): undefined reference to `nvmem_device_read' > This fix does not look correct to me. IMO, This is a issue with incorrect dependencies in the Kconfig, we should not attempt to fix it in the code, rather fix the kconfig dependencies in the mach-davnici or the EEPROM_AT24 kconfig itself. one of them should select the NVMEM. thanks, srini > Also, when NVMEM is completely disabled, the functions fail with > nonobvious error messages. > > This ensures we only call the API functions when the code is actually > reachable from the board file, and otherwise prints a unique log > message. > > Signed-off-by: Arnd Bergmann > Fixes: bec3c11bad0e ("misc: at24: replace memory_accessor with nvmem_device_read") > --- > > Hi Greg, > > The commit that introduced this is currently in the char-misc tree, > please apply this fixup on top if you haven't already sent it to Linus. > > arch/arm/mach-davinci/board-mityomapl138.c | 5 +++++ > arch/arm/mach-davinci/common.c | 5 +++++ > 2 files changed, 10 insertions(+) > > diff --git a/arch/arm/mach-davinci/board-mityomapl138.c b/arch/arm/mach-davinci/board-mityomapl138.c > index d97c588550ad..bc4e63fa9808 100644 > --- a/arch/arm/mach-davinci/board-mityomapl138.c > +++ b/arch/arm/mach-davinci/board-mityomapl138.c > @@ -121,6 +121,11 @@ static void read_factory_config(struct nvmem_device *nvmem, void *context) > const char *partnum = NULL; > struct davinci_soc_info *soc_info = &davinci_soc_info; > > + if (!IS_BUILTIN(CONFIG_NVMEM)) { > + pr_warn("Factory Config not available without CONFIG_NVMEM\n"); > + goto bad_config; > + } > + > ret = nvmem_device_read(nvmem, 0, sizeof(factory_config), > &factory_config); > if (ret != sizeof(struct factory_config)) { > diff --git a/arch/arm/mach-davinci/common.c b/arch/arm/mach-davinci/common.c > index f55ef2ef2f92..742133b7266a 100644 > --- a/arch/arm/mach-davinci/common.c > +++ b/arch/arm/mach-davinci/common.c > @@ -33,6 +33,11 @@ void davinci_get_mac_addr(struct nvmem_device *nvmem, void *context) > char *mac_addr = davinci_soc_info.emac_pdata->mac_addr; > off_t offset = (off_t)context; > > + if (!IS_BUILTIN(CONFIG_NVMEM)) { > + pr_warn("Cannot read MAC addr from EEPROM without CONFIG_NVMEM\n"); > + return; > + } > + > /* Read MAC addr from EEPROM */ > if (nvmem_device_read(nvmem, offset, ETH_ALEN, mac_addr) == ETH_ALEN) > pr_info("Read MAC addr from EEPROM: %pM\n", mac_addr); >