From 1d5ceff25aa1edcaf84e7ee26fdcc746cb245af8 Mon Sep 17 00:00:00 2001 From: "Tudor.Ambarus@microchip.com" Date: Fri, 9 Nov 2018 16:56:54 +0000 Subject: [PATCH] mtd: spi_nor: pass DMA-able buffer to spi_nor_read_raw() spi_nor_read_raw() calls nor->read() which might be implemented by the m25p80 driver. m25p80 uses the spi-mem layer which requires DMA-able in/out buffers. Pass kmalloc'ed dma buffer to spi_nor_read_raw(). Fixes: b038e8e3be72 ("mtd: spi-nor: parse SFDP Sector Map Parameter Table") Signed-off-by: Tudor Ambarus Signed-off-by: Boris Brezillon --- drivers/mtd/spi-nor/spi-nor.c | 15 +++++++++++---- 1 file changed, 11 insertions(+), 4 deletions(-) diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c index 7f03be9b54bc..eb7bb596416b 100644 --- a/drivers/mtd/spi-nor/spi-nor.c +++ b/drivers/mtd/spi-nor/spi-nor.c @@ -2156,7 +2156,7 @@ spi_nor_set_pp_settings(struct spi_nor_pp_command *pp, * @nor: pointer to a 'struct spi_nor' * @addr: offset in the serial flash memory * @len: number of bytes to read - * @buf: buffer where the data is copied into + * @buf: buffer where the data is copied into (dma-safe memory) * * Return: 0 on success, -errno otherwise. */ @@ -2863,11 +2863,17 @@ static const u32 *spi_nor_get_map_in_use(struct spi_nor *nor, const u32 *smpt, u8 smpt_len) { const u32 *ret; + u8 *buf; u32 addr; int err; u8 i; u8 addr_width, read_opcode, read_dummy; - u8 read_data_mask, data_byte, map_id; + u8 read_data_mask, map_id; + + /* Use a kmalloc'ed bounce buffer to guarantee it is DMA-able. */ + buf = kmalloc(sizeof(*buf), GFP_KERNEL); + if (!buf) + return ERR_PTR(-ENOMEM); addr_width = nor->addr_width; read_dummy = nor->read_dummy; @@ -2885,7 +2891,7 @@ static const u32 *spi_nor_get_map_in_use(struct spi_nor *nor, const u32 *smpt, nor->read_opcode = SMPT_CMD_OPCODE(smpt[i]); addr = smpt[i + 1]; - err = spi_nor_read_raw(nor, addr, 1, &data_byte); + err = spi_nor_read_raw(nor, addr, 1, buf); if (err) { ret = ERR_PTR(err); goto out; @@ -2895,7 +2901,7 @@ static const u32 *spi_nor_get_map_in_use(struct spi_nor *nor, const u32 *smpt, * Build an index value that is used to select the Sector Map * Configuration that is currently in use. */ - map_id = map_id << 1 | !!(data_byte & read_data_mask); + map_id = map_id << 1 | !!(*buf & read_data_mask); } /* @@ -2926,6 +2932,7 @@ static const u32 *spi_nor_get_map_in_use(struct spi_nor *nor, const u32 *smpt, /* fall through */ out: + kfree(buf); nor->addr_width = addr_width; nor->read_dummy = read_dummy; nor->read_opcode = read_opcode; -- 2.45.2