spi: s3c64xx: consider the case when the CS line is not connected
When the CS line is not connected, it is not needed to enable or
disable the chip selection functionality from the s3c64xx
devices in order to perform a transfer.
Set the CS controller logically always enabled already during
initialization (by writing '0' in the S3C64XX_SPI_SLAVE_SEL
register) and never disable it.
Signed-off-by: Andi Shyti <andi.shyti@samsung.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 972367d..14269b0 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -315,6 +315,9 @@
struct s3c64xx_spi_driver_data *sdd =
spi_master_get_devdata(spi->master);
+ if (sdd->cntrlr_info->no_cs)
+ return;
+
if (enable) {
if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) {
writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
@@ -960,7 +963,9 @@
sdd->cur_speed = 0;
- if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
+ if (sci->no_cs)
+ writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
+ else if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
/* Disable Interrupts - we use Polling if not DMA mode */
@@ -1015,6 +1020,8 @@
sci->num_cs = temp;
}
+ sci->no_cs = of_property_read_bool(dev->of_node, "broken-cs");
+
return sci;
}
#else