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| author | Leilk Liu <leilk.liu@mediatek.com> | 2015-09-07 19:37:57 +0800 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2015-09-07 17:26:39 +0100 |
| commit | 6583d2032d57df9f1c00c753ca58e1a822901bf0 (patch) | |
| tree | b6721f9a52e34679452377bdcaa591bd79a830f3 | |
| parent | c5992f610f78e6c9d0a78e8fef1066ad640e17e8 (diff) | |
| download | linux-6583d2032d57df9f1c00c753ca58e1a822901bf0.tar.gz linux-6583d2032d57df9f1c00c753ca58e1a822901bf0.tar.bz2 linux-6583d2032d57df9f1c00c753ca58e1a822901bf0.zip | |
spi: mediatek: fix spi cs polarity error
Mediatek spi HW can't set cs inactive(keep cs high) directly.
Instead, it supplies pause mode to do it indirectly. If driver
unsets SPI_CMD_PAUSE_MODE in CMD_REG, it also needs to reset
internal state machine to let cs inactive at once.
Signed-off-by: Leilk Liu <leilk.liu@mediatek.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
| -rw-r--r-- | drivers/spi/spi-mt65xx.c | 27 |
1 files changed, 7 insertions, 20 deletions
diff --git a/drivers/spi/spi-mt65xx.c b/drivers/spi/spi-mt65xx.c index 5f6315c47920..b6073bbff8d9 100644 --- a/drivers/spi/spi-mt65xx.c +++ b/drivers/spi/spi-mt65xx.c @@ -173,22 +173,6 @@ static void mtk_spi_config(struct mtk_spi *mdata, writel(mdata->pad_sel, mdata->base + SPI_PAD_SEL_REG); } -static int mtk_spi_prepare_hardware(struct spi_master *master) -{ - struct spi_transfer *trans; - struct mtk_spi *mdata = spi_master_get_devdata(master); - struct spi_message *msg = master->cur_msg; - - trans = list_first_entry(&msg->transfers, struct spi_transfer, - transfer_list); - if (!trans->cs_change) { - mdata->state = MTK_SPI_IDLE; - mtk_spi_reset(mdata); - } - - return 0; -} - static int mtk_spi_prepare_message(struct spi_master *master, struct spi_message *msg) { @@ -228,11 +212,15 @@ static void mtk_spi_set_cs(struct spi_device *spi, bool enable) struct mtk_spi *mdata = spi_master_get_devdata(spi->master); reg_val = readl(mdata->base + SPI_CMD_REG); - if (!enable) + if (!enable) { reg_val |= SPI_CMD_PAUSE_EN; - else + writel(reg_val, mdata->base + SPI_CMD_REG); + } else { reg_val &= ~SPI_CMD_PAUSE_EN; - writel(reg_val, mdata->base + SPI_CMD_REG); + writel(reg_val, mdata->base + SPI_CMD_REG); + mdata->state = MTK_SPI_IDLE; + mtk_spi_reset(mdata); + } } static void mtk_spi_prepare_transfer(struct spi_master *master, @@ -509,7 +497,6 @@ static int mtk_spi_probe(struct platform_device *pdev) master->mode_bits = SPI_CPOL | SPI_CPHA; master->set_cs = mtk_spi_set_cs; - master->prepare_transfer_hardware = mtk_spi_prepare_hardware; master->prepare_message = mtk_spi_prepare_message; master->transfer_one = mtk_spi_transfer_one; master->can_dma = mtk_spi_can_dma; |