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 <tudor.amba...@microchip.com>
---
v2: drop GFP_DMA, rename buf, add comment
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 04a1c5b825e6..458ca8321999 100644
--- a/drivers/mtd/spi-nor/spi-nor.c
+++ b/drivers/mtd/spi-nor/spi-nor.c
@@ -2161,7 +2161,7 @@ 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.
*/
@@ -2868,11 +2868,17 @@ 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;
@@ -2890,7 +2896,7 @@ 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;
@@ -2900,7 +2906,7 @@ 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);
}
/*
@@ -2931,6 +2937,7 @@ 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;
--
2.9.4
