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    SubjectRe: [PATCH v2 1/5] mtd: spi-nor: notify (Q)SPI controller about protocol change
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    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@atmel.com>
    > >> ---
    > >>
    > >> 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 ! :-)


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