diff options
| author | Clark Wang | 2018-12-07 02:50:38 +0000 |
|---|---|---|
| committer | Mark Brown | 2018-12-13 11:57:28 +0000 |
| commit | cf86874bb9bdb99ba3620428b59b0408fbc703d0 (patch) | |
| tree | ff44f80e499856282f2c9395fdff9d13b901dfca | |
| parent | bcd87317aae26b9ac497cbc1232783aaea1aeed4 (diff) | |
spi: lpspi: Let watermark change with send data length
Configure watermark to change with the length of the sent data.
Support LPSPI sending message shorter than tx/rxfifosize.
Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
| -rw-r--r-- | drivers/spi/spi-fsl-lpspi.c | 11 |
1 files changed, 9 insertions, 2 deletions
diff --git a/drivers/spi/spi-fsl-lpspi.c b/drivers/spi/spi-fsl-lpspi.c index cbf165e7bd17..08dcc3c22e88 100644 --- a/drivers/spi/spi-fsl-lpspi.c +++ b/drivers/spi/spi-fsl-lpspi.c @@ -89,6 +89,7 @@ struct fsl_lpspi_data { void (*rx)(struct fsl_lpspi_data *); u32 remain; + u8 watermark; u8 txfifosize; u8 rxfifosize; @@ -235,7 +236,7 @@ static void fsl_lpspi_set_watermark(struct fsl_lpspi_data *fsl_lpspi) { u32 temp; - temp = fsl_lpspi->txfifosize >> 1 | (fsl_lpspi->rxfifosize >> 1) << 16; + temp = fsl_lpspi->watermark >> 1 | (fsl_lpspi->watermark >> 1) << 16; writel(temp, fsl_lpspi->base + IMX7ULP_FCR); @@ -261,7 +262,8 @@ static int fsl_lpspi_set_bitrate(struct fsl_lpspi_data *fsl_lpspi) if (prescale == 8 && scldiv >= 256) return -EINVAL; - writel(scldiv, fsl_lpspi->base + IMX7ULP_CCR); + writel(scldiv | (scldiv << 8) | ((scldiv >> 1) << 16), + fsl_lpspi->base + IMX7ULP_CCR); dev_dbg(fsl_lpspi->dev, "perclk=%d, speed=%d, prescale =%d, scldiv=%d\n", perclk_rate, config.speed_hz, prescale, scldiv); @@ -329,6 +331,11 @@ static void fsl_lpspi_setup_transfer(struct spi_device *spi, fsl_lpspi->tx = fsl_lpspi_buf_tx_u32; } + if (t->len <= fsl_lpspi->txfifosize) + fsl_lpspi->watermark = t->len; + else + fsl_lpspi->watermark = fsl_lpspi->txfifosize; + fsl_lpspi_config(fsl_lpspi); } |