On Wednesday, July 22, 2015 at 06:25:20 PM, Cyrille Pitchen wrote: > Hi Marek, > > Le 22/07/2015 15:41, Marek Vasut a écrit : > > On Wednesday, July 22, 2015 at 03:17:06 PM, Cyrille Pitchen wrote: > >> Once the Quad SPI mode has been enabled on a Micron flash memory, this > >> device expects ALL the following commands to use the SPI 4-4-4 protocol. > >> The (Q)SPI controller needs to be notified about the protocol change so > >> it can adapt and keep on dialoging with the Micron memory. > >> > >> Signed-off-by: Cyrille Pitchen <cyrille.pitchen@xxxxxxxxx> > >> --- > >> > >> drivers/mtd/spi-nor/spi-nor.c | 17 +++++++++++++++++ > >> include/linux/mtd/spi-nor.h | 13 +++++++++++++ > >> 2 files changed, 30 insertions(+) > >> > >> diff --git a/drivers/mtd/spi-nor/spi-nor.c > >> b/drivers/mtd/spi-nor/spi-nor.c index d78831b4422b..93627d4e6be8 100644 > >> --- a/drivers/mtd/spi-nor/spi-nor.c > >> +++ b/drivers/mtd/spi-nor/spi-nor.c > >> @@ -163,6 +163,18 @@ static inline int write_disable(struct spi_nor > >> *nor) > >> > >> return nor->write_reg(nor, SPINOR_OP_WRDI, NULL, 0, 0); > >> > >> } > >> > >> +/* > >> + * Notify the (Q)SPI controller about the new protocol to be used. > > > > Hi! > > > > Can you please just reword this a little, so that it is absolutelly clear > > even to the less bright of us (like me) that this is a notification > > coming from the upper layers (ie. the spi-nor framework) toward the > > hardware ? > > Sure, no problem! what about the following? > > /* > * Let the spi-nor framework notify lower layers, especially the driver of > the * (Q)SPI controller, about the new protocol to be used. Indeed, once > the * spi-nor framework has sent manufacturer specific commands to a > memory to * enable its Quad SPI mode, it should immediately after tell the > QSPI * controller to use the very same Quad SPI protocol as expected by > the memory. */ Sure, excellent, thanks ! :-) -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
