spi: dw: introduce support of loopback mode

For testing purposes it's good to have a loopback mode enabled. The patch adds
necessary bits for that.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
This commit is contained in:
Andy Shevchenko 2014-09-18 20:08:56 +03:00 committed by Mark Brown
parent 8e45ef682c
commit c3ce15bf2a

View File

@ -591,6 +591,9 @@ static int dw_spi_setup(struct spi_device *spi)
| (spi->mode << SPI_MODE_OFFSET)
| (chip->tmode << SPI_TMOD_OFFSET);
if (spi->mode & SPI_LOOP)
chip->cr0 |= 1 << SPI_SRL_OFFSET;
if (gpio_is_valid(spi->cs_gpio)) {
ret = gpio_direction_output(spi->cs_gpio,
!(spi->mode & SPI_CS_HIGH));
@ -652,7 +655,7 @@ int dw_spi_add_host(struct device *dev, struct dw_spi *dws)
goto err_free_master;
}
master->mode_bits = SPI_CPOL | SPI_CPHA;
master->mode_bits = SPI_CPOL | SPI_CPHA | SPI_LOOP;
master->bits_per_word_mask = SPI_BPW_MASK(8) | SPI_BPW_MASK(16);
master->bus_num = dws->bus_num;
master->num_chipselect = dws->num_cs;