From mboxrd@z Thu Jan 1 00:00:00 1970 From: Michal Suchanek Subject: [PATCH 2/3] MTD: spi-nor: check for short writes in spi_nor_write. Date: Thu, 30 Apr 2015 15:38:50 +0200 Message-ID: <50c40ef17ab6566f35ef5a4426bf23567f896db7.1430403750.git.hramrach@gmail.com> References: Reply-To: hramrach-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Return-path: In-Reply-To: List-Post: , List-Help: , List-Archive: , List-Unsubscribe: , To: linux-sunxi-/JYPxA39Uh5TLH3MbocFFw@public.gmane.org, Rob Herring , Pawel Moll , Mark Rutland , Ian Campbell , Kumar Gala , David Woodhouse , Brian Norris , Marek Vasut , Huang Shijie , Michal Suchanek , Ben Hutchings , Alison Chaiken , Mika Westerberg , "grmoore-EIB2kfCEclfQT0dZR+AlfA@public.gmane.org" , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-mtd-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: devicetree@vger.kernel.org My SPI controller driver does not support DMA so writes are truncated to FIFO size. Check the amount of data actually written by the driver. Signed-off-by: Michal Suchanek --- drivers/mtd/spi-nor/spi-nor.c | 42 +++++++++++++++++------------------------- 1 file changed, 17 insertions(+), 25 deletions(-) diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c index 14a5d23..75904b5 100644 --- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -807,7 +807,7 @@ static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len, size_t *retlen, const u_char *buf) { struct spi_nor *nor = mtd_to_spi_nor(mtd); - u32 page_offset, page_size, i; + u32 page_offset, page_remainder, page_size, i; int ret; dev_dbg(nor->dev, "to 0x%08x, len %zd\n", (u32)to, len); @@ -816,36 +816,28 @@ static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len, if (ret) return ret; - write_enable(nor); - - page_offset = to & (nor->page_size - 1); - - /* do all the bytes fit onto one page? */ - if (page_offset + len <= nor->page_size) { - nor->write(nor, to, len, retlen, buf); - } else { - /* the size of data remaining on the first page */ - page_size = nor->page_size - page_offset; - nor->write(nor, to, page_size, retlen, buf); + /* write everything in nor->page_size chunks */ + /* check the size of data actually written */ + for (i = 0; i < len; i += *retlen) { + page_size = len - i; + page_offset = (to + i) & (nor->page_size - 1); + page_remainder = nor->page_size - page_offset; + if (page_size > nor->page_size) + page_size = nor->page_size; + if (page_remainder && (page_size > page_remainder)) + page_size = page_remainder; - /* write everything in nor->page_size chunks */ - for (i = page_size; i < len; i += page_size) { - page_size = len - i; - if (page_size > nor->page_size) - page_size = nor->page_size; - - ret = spi_nor_wait_till_ready(nor); - if (ret) - goto write_err; + write_enable(nor); - write_enable(nor); + nor->write(nor, to + i, page_size, retlen, buf + i); - nor->write(nor, to + i, page_size, retlen, buf + i); - } + ret = spi_nor_wait_till_ready(nor); + if (ret) + goto write_err; } - ret = spi_nor_wait_till_ready(nor); write_err: + *retlen = i; spi_nor_unlock_and_unprep(nor, SPI_NOR_OPS_WRITE); return ret; } -- 2.1.4