diff options
Diffstat (limited to 'drivers/spi/spi-omap2-mcspi.c')
| -rw-r--r-- | drivers/spi/spi-omap2-mcspi.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/drivers/spi/spi-omap2-mcspi.c b/drivers/spi/spi-omap2-mcspi.c index 3d09e0b69..1f8903d35 100644 --- a/drivers/spi/spi-omap2-mcspi.c +++ b/drivers/spi/spi-omap2-mcspi.c @@ -1217,6 +1217,33 @@ out: return status; } +static int omap2_mcspi_prepare_message(struct spi_master *master, + struct spi_message *msg) +{ + struct omap2_mcspi *mcspi = spi_master_get_devdata(master); + struct omap2_mcspi_regs *ctx = &mcspi->ctx; + struct omap2_mcspi_cs *cs; + + /* Only a single channel can have the FORCE bit enabled + * in its chconf0 register. + * Scan all channels and disable them except the current one. + * A FORCE can remain from a last transfer having cs_change enabled + */ + list_for_each_entry(cs, &ctx->cs, node) { + if (msg->spi->controller_state == cs) + continue; + + if ((cs->chconf0 & OMAP2_MCSPI_CHCONF_FORCE)) { + cs->chconf0 &= ~OMAP2_MCSPI_CHCONF_FORCE; + writel_relaxed(cs->chconf0, + cs->base + OMAP2_MCSPI_CHCONF0); + readl_relaxed(cs->base + OMAP2_MCSPI_CHCONF0); + } + } + + return 0; +} + static int omap2_mcspi_transfer_one(struct spi_master *master, struct spi_device *spi, struct spi_transfer *t) { @@ -1344,6 +1371,7 @@ static int omap2_mcspi_probe(struct platform_device *pdev) master->bits_per_word_mask = SPI_BPW_RANGE_MASK(4, 32); master->setup = omap2_mcspi_setup; master->auto_runtime_pm = true; + master->prepare_message = omap2_mcspi_prepare_message; master->transfer_one = omap2_mcspi_transfer_one; master->set_cs = omap2_mcspi_set_cs; master->cleanup = omap2_mcspi_cleanup; |