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    SubjectRe: [PATCHv2] drivers: spi: Add qspi flash controller
    Hi,

    Alright, so I spent some time looking at the SPI framework and :

    On Tue, Jul 02, 2013 at 02:26:39PM +0530, Sourav Poddar wrote:
    > +static int dra7xxx_qspi_start_transfer_one(struct spi_master *master,
    > + struct spi_message *m)
    > +{
    > + struct dra7xxx_qspi *qspi = spi_master_get_devdata(master);
    > + struct spi_device *spi = m->spi;
    > + struct spi_transfer *t;
    > + int status = 0;
    > + int flags = 0;
    > +
    > + /* setup command reg */
    > + qspi->cmd = 0;
    > + qspi->cmd |= QSPI_WLEN(8);

    this m->spi->bits_per_word;

    > + qspi->cmd |= QSPI_EN_CS(0);

    this should be m->spi->chip_select;

    > + qspi->cmd |= 0xfff;

    this will be a little tricky to count... because, I believe it should be
    something like:

    int count = 0;

    list_for_each_entry(t, &m->transfers, transfer_list)
    count += t->len;

    frame_length = DIV_ROUND_UP(count, m->spi->bits_per_word);

    /* up to 4096 words */
    frame_length = clamp(frame_length, 4096);

    qspi->cmd |= QSPI_FRAME_LENGTH(DIV_ROUND_UP(count,
    frame_length));

    Now, it would've been better if SPI framework would already give us
    some sort of total_length field in struct spi_message which would be the
    sum of all spi_transfers.

    > + /* setup device control reg */
    > + qspi->dc = 0;
    > +
    > + if (spi->mode & SPI_CPHA)
    > + qspi->dc |= QSPI_CKPHA(0);
    > + if (spi->mode & SPI_CPOL)
    > + qspi->dc |= QSPI_CKPOL(0);
    > + if (spi->mode & SPI_CS_HIGH)
    > + qspi->dc |= QSPI_CSPOL(0);

    all of these zeroes being passed to these macros should be
    m->spi->chip_select

    --
    balbi
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