From 60e2bf46784ebbd30ff29b3d3c7c97e56b11e86a Mon Sep 17 00:00:00 2001 From: Weijie Gao Date: Fri, 26 Apr 2019 17:22:19 +0800 Subject: [PATCH] mtd: spi-nor: fix page program issue when using spi-mem driver Some SPI controllers can't write nor->page_size bytes in a single step because their TX FIFO is too small, but when that happens we should make sure a WRITE_EN command before each write access and READ_SR command after each write access is issued. We should allow nor->write() to return a size that is smaller than the requested write size to gracefully handle this case. Also, the spi_nor_write_data() should return the actual number of bytes that were written during the spi_mem_exec_op() operation. This patch is a combination of two commits backported from kernel: commit 630d6bd8a3b4 ("mtd: spi-nor: Support controllers with limit ...") commit 3baa8ec88c2f ("mtd: devices: m25p80: Make sure WRITE_EN is ...") Cc: Vignesh R Signed-off-by: Weijie Gao Acked-by: Vignesh R Tested-by: Shyam Saini # microzed Acked-by: Jagan Teki --- drivers/mtd/spi/spi-nor-core.c | 27 ++++++++------------------- 1 file changed, 8 insertions(+), 19 deletions(-) diff --git a/drivers/mtd/spi/spi-nor-core.c b/drivers/mtd/spi/spi-nor-core.c index c4e2f6a..1acff74 100644 --- a/drivers/mtd/spi/spi-nor-core.c +++ b/drivers/mtd/spi/spi-nor-core.c @@ -116,7 +116,6 @@ static ssize_t spi_nor_write_data(struct spi_nor *nor, loff_t to, size_t len, SPI_MEM_OP_ADDR(nor->addr_width, to, 1), SPI_MEM_OP_NO_DUMMY, SPI_MEM_OP_DATA_OUT(len, buf, 1)); - size_t remaining = len; int ret; /* get transfer protocols. */ @@ -127,22 +126,16 @@ static ssize_t spi_nor_write_data(struct spi_nor *nor, loff_t to, size_t len, if (nor->program_opcode == SPINOR_OP_AAI_WP && nor->sst_write_second) op.addr.nbytes = 0; - while (remaining) { - op.data.nbytes = remaining < UINT_MAX ? remaining : UINT_MAX; - ret = spi_mem_adjust_op_size(nor->spi, &op); - if (ret) - return ret; - - ret = spi_mem_exec_op(nor->spi, &op); - if (ret) - return ret; + ret = spi_mem_adjust_op_size(nor->spi, &op); + if (ret) + return ret; + op.data.nbytes = len < op.data.nbytes ? len : op.data.nbytes; - op.addr.val += op.data.nbytes; - remaining -= op.data.nbytes; - op.data.buf.out += op.data.nbytes; - } + ret = spi_mem_exec_op(nor->spi, &op); + if (ret) + return ret; - return len; + return op.data.nbytes; } /* @@ -1101,10 +1094,6 @@ static int spi_nor_write(struct mtd_info *mtd, loff_t to, size_t len, goto write_err; *retlen += written; i += written; - if (written != page_remain) { - ret = -EIO; - goto write_err; - } } write_err: -- 2.7.4