diff options
| author | Uwe Kleine-König <u.kleine-koenig@pengutronix.de> | 2021-07-27 14:42:26 +0200 |
|---|---|---|
| committer | Mark Brown <broonie@kernel.org> | 2021-08-03 01:45:10 +0100 |
| commit | 6e95b23a5b2d1fcbe5a84a362170a4871a3d5731 (patch) | |
| tree | a56c70506cd3295dfb20b9b8d22ec98357609ab4 /drivers/spi/spi-imx.c | |
| parent | e3aa9acc71778266cc4743217ff1a1a53caf15d6 (diff) | |
spi: imx: Implement support for CS_WORD
This only works when the native chipselect is in use. On a board with a
Ti ADS7950 8 channel ADC. This patch reduces the time to read out all
channels once from 280 us to 20 us.
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20210727124226.5571-1-u.kleine-koenig@pengutronix.de
Signed-off-by: Mark Brown <broonie@kernel.org>
Diffstat (limited to 'drivers/spi/spi-imx.c')
| -rw-r--r-- | drivers/spi/spi-imx.c | 10 |
1 files changed, 10 insertions, 0 deletions
diff --git a/drivers/spi/spi-imx.c b/drivers/spi/spi-imx.c index 593b63be73de..340fd1245bc2 100644 --- a/drivers/spi/spi-imx.c +++ b/drivers/spi/spi-imx.c @@ -1176,6 +1176,7 @@ static int spi_imx_setupxfer(struct spi_device *spi, * dynamic_burst in that case. */ if (spi_imx->devtype_data->dynamic_burst && !spi_imx->slave_mode && + !(spi->mode & SPI_CS_WORD) && (spi_imx->bits_per_word == 8 || spi_imx->bits_per_word == 16 || spi_imx->bits_per_word == 32)) { @@ -1611,6 +1612,15 @@ static int spi_imx_probe(struct platform_device *pdev) is_imx53_ecspi(spi_imx)) spi_imx->bitbang.master->mode_bits |= SPI_LOOP | SPI_READY; + if (is_imx51_ecspi(spi_imx) && + device_property_read_u32(&pdev->dev, "cs-gpios", NULL)) + /* + * When using HW-CS implementing SPI_CS_WORD can be done by just + * setting the burst length to the word size. This is + * considerably faster than manually controlling the CS. + */ + spi_imx->bitbang.master->mode_bits |= SPI_CS_WORD; + spi_imx->spi_drctl = spi_drctl; init_completion(&spi_imx->xfer_done); |