[PATCH] spi: s3c64xx: group the CS signalling writes in a single function

From: Andi Shyti
Date: Mon Jun 27 2016 - 22:41:11 EST


To enable/disable the CS line, the driver performs a writel in
the S3C64XX_SPI_SLAVE_SEL registers. Group the register's
configuration in a single function.

Signed-off-by: Andi Shyti <andi.shyti@xxxxxxxxxxx>
Signed-off-by: Mark Brown <broonie@xxxxxxxxxx>
---
drivers/spi/spi-s3c64xx.c | 36 ++++++++++++++++++++++++++----------
1 file changed, 26 insertions(+), 10 deletions(-)

diff --git a/drivers/spi/spi-s3c64xx.c b/drivers/spi/spi-s3c64xx.c
index 5a76a50063b5..972367d5c7f2 100644
--- a/drivers/spi/spi-s3c64xx.c
+++ b/drivers/spi/spi-s3c64xx.c
@@ -310,6 +310,28 @@ static void prepare_dma(struct s3c64xx_spi_dma_data *dma,
dma_async_issue_pending(dma->ch);
}

+static void s3c64xx_spi_set_cs(struct spi_device *spi, bool enable)
+{
+ struct s3c64xx_spi_driver_data *sdd =
+ spi_master_get_devdata(spi->master);
+
+ if (enable) {
+ if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO)) {
+ writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
+ } else {
+ u32 ssel = readl(sdd->regs + S3C64XX_SPI_SLAVE_SEL);
+
+ ssel |= (S3C64XX_SPI_SLAVE_AUTO |
+ S3C64XX_SPI_SLAVE_NSC_CNT_2);
+ writel(ssel, 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);
+ }
+}
+
static int s3c64xx_spi_prepare_transfer(struct spi_master *spi)
{
struct s3c64xx_spi_driver_data *sdd = spi_master_get_devdata(spi);
@@ -706,12 +728,7 @@ static int s3c64xx_spi_transfer_one(struct spi_master *master,
enable_datapath(sdd, spi, xfer, use_dma);

/* Start the signals */
- if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
- writel(0, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
- else
- writel(readl(sdd->regs + S3C64XX_SPI_SLAVE_SEL)
- | S3C64XX_SPI_SLAVE_AUTO | S3C64XX_SPI_SLAVE_NSC_CNT_2,
- sdd->regs + S3C64XX_SPI_SLAVE_SEL);
+ s3c64xx_spi_set_cs(spi, true);

spin_unlock_irqrestore(&sdd->lock, flags);

@@ -861,16 +878,15 @@ static int s3c64xx_spi_setup(struct spi_device *spi)

pm_runtime_mark_last_busy(&sdd->pdev->dev);
pm_runtime_put_autosuspend(&sdd->pdev->dev);
- if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
- writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
+ s3c64xx_spi_set_cs(spi, false);
+
return 0;

setup_exit:
pm_runtime_mark_last_busy(&sdd->pdev->dev);
pm_runtime_put_autosuspend(&sdd->pdev->dev);
/* setup() returns with device de-selected */
- if (!(sdd->port_conf->quirks & S3C64XX_SPI_QUIRK_CS_AUTO))
- writel(S3C64XX_SPI_SLAVE_SIG_INACT, sdd->regs + S3C64XX_SPI_SLAVE_SEL);
+ s3c64xx_spi_set_cs(spi, false);

if (gpio_is_valid(spi->cs_gpio))
gpio_free(spi->cs_gpio);
--
2.8.1