Hello, On 29 March 2016 at 07:46, Vignesh R <vigne...@ti.com> wrote: > Certain SPI controllers may provide accelerated hardware interface to > read from m25p80 type flash devices in order to provide better read > performance. SPI core supports such devices with spi_flash_read() API. > Call spi_flash_read(), if supported, to make use of such interface. > > Signed-off-by: Vignesh R <vigne...@ti.com> > --- > > Resend v5: > Rebased on top of v4.6-rc1 > v5: http://www.spinics.net/lists/devicetree/msg106696.html > > drivers/mtd/devices/m25p80.c | 20 ++++++++++++++++++++ > 1 file changed, 20 insertions(+) > > diff --git a/drivers/mtd/devices/m25p80.c b/drivers/mtd/devices/m25p80.c > index c9c3b7fa3051..7730e633d7d3 100644 > --- a/drivers/mtd/devices/m25p80.c > +++ b/drivers/mtd/devices/m25p80.c > @@ -131,6 +131,26 @@ static int m25p80_read(struct spi_nor *nor, loff_t from, > size_t len, > /* convert the dummy cycles to the number of bytes */ > dummy /= 8; > > + if (spi_flash_read_supported(spi)) { > + struct spi_flash_read_message msg; > + int ret; > + > + msg.buf = buf; > + msg.from = from; > + msg.len = len; > + msg.read_opcode = nor->read_opcode; > + msg.addr_width = nor->addr_width; > + msg.dummy_bytes = dummy; > + /* TODO: Support other combinations */ > + msg.opcode_nbits = SPI_NBITS_SINGLE; > + msg.addr_nbits = SPI_NBITS_SINGLE; > + msg.data_nbits = m25p80_rx_nbits(nor); > + > + ret = spi_flash_read(spi, &msg); > + *retlen = msg.retlen;
This is wrong. The previous retlen is never passed into msg so it must be added and not assigned as is seen a few lines below: ret = m.actual_length - m25p_cmdsz(nor) - dummy; if (ret < 0) return -EIO; *retlen += ret; This interface with odd design and poor documentation will be hopefully weeded out with mtd: spi-nor: stop passing around retlen so there is probably no need to patch this separately. Thanks Michal