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[36.2.101.155]) by smtp.gmail.com with ESMTPSA id z4-20020a17090a66c400b001f94d25bfabsm9257936pjl.28.2022.12.19.07.12.53 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 19 Dec 2022 07:12:56 -0800 (PST) Message-ID: Date: Tue, 20 Dec 2022 00:12:52 +0900 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.13.1 From: Tokunori Ikegami Subject: Re: [PATCH] mtd: cfi: allow building spi-intel standalone To: Arnd Bergmann , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra Cc: Arnd Bergmann , Lee Jones , Mauro Lima , Tudor Ambarus , Mika Westerberg , Boris Brezillon , linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org References: <20221215163950.649791-1-arnd@kernel.org> Content-Language: en-US In-Reply-To: <20221215163950.649791-1-arnd@kernel.org> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20221219_071316_756791_35CEC995 X-CRM114-Status: GOOD ( 20.97 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: base64 Content-Type: text/plain; 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[36.2.101.155]) by smtp.gmail.com with ESMTPSA id z4-20020a17090a66c400b001f94d25bfabsm9257936pjl.28.2022.12.19.07.12.53 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Mon, 19 Dec 2022 07:12:56 -0800 (PST) Message-ID: Date: Tue, 20 Dec 2022 00:12:52 +0900 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:91.0) Gecko/20100101 Thunderbird/91.13.1 From: Tokunori Ikegami Subject: Re: [PATCH] mtd: cfi: allow building spi-intel standalone To: Arnd Bergmann , Miquel Raynal , Richard Weinberger , Vignesh Raghavendra Cc: Arnd Bergmann , Lee Jones , Mauro Lima , Tudor Ambarus , Mika Westerberg , Boris Brezillon , linux-mtd@lists.infradead.org, linux-kernel@vger.kernel.org References: <20221215163950.649791-1-arnd@kernel.org> Content-Language: en-US In-Reply-To: <20221215163950.649791-1-arnd@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 2022/12/16 1:39, Arnd Bergmann wrote: > From: Arnd Bergmann > > When MTD or MTD_CFI_GEOMETRY is disabled, the spi-intel driver > fails to build, as it includes the shared CFI header: The header file linux/mtd/cfi.h is included by the head file linux/mtd/spi-nor.h so seems the warning caused. Is it really necessary to inculude linux/mtd/cfi.h from linux/mtd/spi-nor.h? (It seems that it can be resolved the issue by removing the including cfi.h from spi-nor.h if unnecessary.) > > include/linux/mtd/cfi.h:62:2: error: #warning No CONFIG_MTD_CFI_Ix selected. No NOR chip support can work. [-Werror=cpp] > 62 | #warning No CONFIG_MTD_CFI_Ix selected. No NOR chip support can work. > > Use an #ifdef here to guard the settings so the header can be included > in all configurations. > > Fixes: e23e5a05d1fd ("mtd: spi-nor: intel-spi: Convert to SPI MEM") > Signed-off-by: Arnd Bergmann > --- > include/linux/mtd/cfi.h | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/include/linux/mtd/cfi.h b/include/linux/mtd/cfi.h > index d88bb56c18e2..0e87b6e2faad 100644 > --- a/include/linux/mtd/cfi.h > +++ b/include/linux/mtd/cfi.h > @@ -15,6 +15,7 @@ > #include > #include > > +#if IS_ENABLED(CONFIG_MTD) Is it enough to check only CONFIG_MTD here as not necessary to check if MTD_CFI_GEOMETRY also? By the way it seems also that it is needed to use #ifdef only for the cfi_interleave warning checking as below. #if IS_ENABLED(CONFIG_MTD) && IS_ENABLED(CONFIG_MTD_CFI_GEOMETRY) #ifndef cfi_interleave #warning No CONFIG_MTD_CFI_Ix selected. No NOR chip support can work. static inline int cfi_interleave(void *cfi) {     BUG();     return 0; } #endif /* cfi_interleave */ #endif /* IS_ENABLED(CONFIG_MTD) && IS_ENABLED(CONFIG_MTD_CFI_GEOMETRY) */ Note: The cfi_interleave warning checking was implemented by the following commit.   241651d04d67 ("[MTD] Fix CFI build error when no map width or interleave supported") > #ifdef CONFIG_MTD_CFI_I1 > #define cfi_interleave(cfi) 1 > #define cfi_interleave_is_1(cfi) (cfi_interleave(cfi) == 1) > @@ -88,7 +89,7 @@ static inline int cfi_interleave_supported(int i) > return 0; > } > } > - > +#endif > > /* NB: these values must represents the number of bytes needed to meet the > * device type (x8, x16, x32). Eg. a 32 bit device is 4 x 8 bytes.