spi: spi-mpc512x-psc: add support for gpio chip selects
Currently the driver only uses one internal chip select.
Add support for gpio chip selects configured by cs-gpios
DT binding.
Signed-off-by: Anatolij Gustschin <agust@denx.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
diff --git a/drivers/spi/spi-mpc512x-psc.c b/drivers/spi/spi-mpc512x-psc.c
index 3e490ee..da60f26 100644
--- a/drivers/spi/spi-mpc512x-psc.c
+++ b/drivers/spi/spi-mpc512x-psc.c
@@ -28,6 +28,7 @@
#include <linux/clk.h>
#include <linux/spi/spi.h>
#include <linux/fsl_devices.h>
+#include <linux/gpio.h>
#include <asm/mpc52xx_psc.h>
struct mpc512x_psc_spi {
@@ -113,7 +114,7 @@
out_be32(&psc->ccr, ccr);
mps->bits_per_word = cs->bits_per_word;
- if (mps->cs_control)
+ if (mps->cs_control && gpio_is_valid(spi->cs_gpio))
mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 1 : 0);
}
@@ -121,7 +122,7 @@
{
struct mpc512x_psc_spi *mps = spi_master_get_devdata(spi->master);
- if (mps->cs_control)
+ if (mps->cs_control && gpio_is_valid(spi->cs_gpio))
mps->cs_control(spi, (spi->mode & SPI_CS_HIGH) ? 0 : 1);
}
@@ -278,6 +279,7 @@
struct mpc512x_psc_spi *mps = spi_master_get_devdata(spi->master);
struct mpc512x_psc_spi_cs *cs = spi->controller_state;
unsigned long flags;
+ int ret;
if (spi->bits_per_word % 8)
return -EINVAL;
@@ -286,6 +288,19 @@
cs = kzalloc(sizeof *cs, GFP_KERNEL);
if (!cs)
return -ENOMEM;
+
+ if (gpio_is_valid(spi->cs_gpio)) {
+ ret = gpio_request(spi->cs_gpio, dev_name(&spi->dev));
+ if (ret) {
+ dev_err(&spi->dev, "can't get CS gpio: %d\n",
+ ret);
+ kfree(cs);
+ return ret;
+ }
+ gpio_direction_output(spi->cs_gpio,
+ spi->mode & SPI_CS_HIGH ? 0 : 1);
+ }
+
spi->controller_state = cs;
}
@@ -319,6 +334,8 @@
static void mpc512x_psc_spi_cleanup(struct spi_device *spi)
{
+ if (gpio_is_valid(spi->cs_gpio))
+ gpio_free(spi->cs_gpio);
kfree(spi->controller_state);
}
@@ -405,6 +422,11 @@
return IRQ_NONE;
}
+static void mpc512x_spi_cs_control(struct spi_device *spi, bool onoff)
+{
+ gpio_set_value(spi->cs_gpio, onoff);
+}
+
/* bus_num is used only for the case dev->platform_data == NULL */
static int mpc512x_psc_spi_do_probe(struct device *dev, u32 regaddr,
u32 size, unsigned int irq,
@@ -425,12 +447,9 @@
mps->irq = irq;
if (pdata == NULL) {
- dev_err(dev, "probe called without platform data, no "
- "cs_control function will be called\n");
- mps->cs_control = NULL;
+ mps->cs_control = mpc512x_spi_cs_control;
mps->sysclk = 0;
master->bus_num = bus_num;
- master->num_chipselect = 255;
} else {
mps->cs_control = pdata->cs_control;
mps->sysclk = pdata->sysclk;