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| author |   Boris Brezillon <boris.brezillon@bootlin.com> | 2018-09-17 16:31:30 +0200 |
|---|---|---|
| committer | Boris Brezillon <boris.brezillon@bootlin.com> | 2018-09-18 10:17:48 +0200 |
| commit | 4a3e85f2674cbfb81052059107d0165269778e2f (patch) | |
| tree | 88e32db1e0460c11dda408086e7f3d9c1399ef43 /drivers/mtd | |
| parent | mtd: partitions: fix unbalanced of_node_get/put() (diff) | |
| download | linux-dev-4a3e85f2674cbfb81052059107d0165269778e2f.tar.xz linux-dev-4a3e85f2674cbfb81052059107d0165269778e2f.zip | |
mtd: devices: m25p80: Make sure the buffer passed in op is DMA-able
As documented in spi-mem.h, spi_mem_op->data.buf.{in,out} must be
DMA-able, and commit 4120f8d158ef ("mtd: spi-nor: Use the spi_mem_xx()
API") failed to follow this rule as buffers passed to
->{read,write}_reg() are usually placed on the stack.
Fix that by allocating a scratch buffer and copying the data around.
Fixes: 4120f8d158ef ("mtd: spi-nor: Use the spi_mem_xx() API")
Reported-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Boris Brezillon <boris.brezillon@bootlin.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Reviewed-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Diffstat (limited to 'drivers/mtd')
| -rw-r--r-- | drivers/mtd/devices/m25p80.c | 26 |
1 files changed, 23 insertions, 3 deletions
diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c index cbfafc453274..270d3c9580c5 100644 --- a/drivers/mtd/devices/m25p80.c +++ b/drivers/mtd/devices/m25p80.c @@ -39,13 +39,23 @@ static int m25p80_read_reg(struct spi_nor *nor, u8 code, u8 *val, int len) struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(code, 1), SPI_MEM_OP_NO_ADDR, SPI_MEM_OP_NO_DUMMY, - SPI_MEM_OP_DATA_IN(len, val, 1)); + SPI_MEM_OP_DATA_IN(len, NULL, 1)); + void *scratchbuf; int ret; + scratchbuf = kmalloc(len, GFP_KERNEL); + if (!scratchbuf) + return -ENOMEM; + + op.data.buf.in = scratchbuf; ret = spi_mem_exec_op(flash->spimem, &op); if (ret < 0) dev_err(&flash->spimem->spi->dev, "error %d reading %x\n", ret, code); + else + memcpy(val, scratchbuf, len); + + kfree(scratchbuf); return ret; } @@ -56,9 +66,19 @@ static int m25p80_write_reg(struct spi_nor *nor, u8 opcode, u8 *buf, int len) struct spi_mem_op op = SPI_MEM_OP(SPI_MEM_OP_CMD(opcode, 1), SPI_MEM_OP_NO_ADDR, SPI_MEM_OP_NO_DUMMY, - SPI_MEM_OP_DATA_OUT(len, buf, 1)); + SPI_MEM_OP_DATA_OUT(len, NULL, 1)); + void *scratchbuf; + int ret; - return spi_mem_exec_op(flash->spimem, &op); + scratchbuf = kmemdup(buf, len, GFP_KERNEL); + if (!scratchbuf) + return -ENOMEM; + + op.data.buf.out = scratchbuf; + ret = spi_mem_exec_op(flash->spimem, &op); + kfree(scratchbuf); + + return ret; } static ssize_t m25p80_write(struct spi_nor *nor, loff_t to, size_t len, |