On Sunday, September 28, 2014 at 03:59:42 AM, bpqw wrote: > For Micron spi norflash,you can enable > Quad spi transfer by clear EVCR(Enhanced > Volatile Configuration Register) Quad I/O > protocol bit.
OK, this information is nice and all, but what does this patch do? I can't learn this information from the commit message as it is, can I ? And , the purpose of the commit message is exactly to summarize the change the patch implements. > Signed-off-by: bean huo <[email protected]> > --- > v1-v2:modified to that capture wait_till_ready() > return value,if error,directly return its > the value. > > drivers/mtd/spi-nor/spi-nor.c | 46 > +++++++++++++++++++++++++++++++++++++++++ include/linux/mtd/spi-nor.h | > 6 ++++++ > 2 files changed, 52 insertions(+) > > diff --git a/drivers/mtd/spi-nor/spi-nor.c b/drivers/mtd/spi-nor/spi-nor.c > index b5ad6be..0c3b4fd 100644 > --- a/drivers/mtd/spi-nor/spi-nor.c > +++ b/drivers/mtd/spi-nor/spi-nor.c > @@ -878,6 +878,45 @@ static int spansion_quad_enable(struct spi_nor *nor) > return 0; > } > > +static int micron_quad_enable(struct spi_nor *nor) > +{ > + int ret, val; > + > + ret = nor->read_reg(nor, SPINOR_OP_RD_EVCR, &val, 1); > + if (ret < 0) { > + dev_err(nor->dev, "error %d reading EVCR\n", ret); > + return -EINVAL; > + } > + > + write_enable(nor); > + > + /* set EVCR ,enable quad I/O */ > + nor->cmd_buf[0] = val & ~EVCR_QUAD_EN_MICRON; > + ret = nor->write_reg(nor, SPINOR_OP_WD_EVCR, nor->cmd_buf, 1, 0); > + if (ret < 0) { > + dev_err(nor->dev, > + "error while writing EVCR register\n"); > + return -EINVAL; Why not just "return ret;" ? [...] -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
