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 3e490ee7f275be30447ce5a3030f7872da634695..da60f268f74ced9078e3e5528322546297b854dc 100644 (file)
--- 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 @@ static void mpc512x_psc_spi_activate_cs(struct spi_device *spi)
        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 @@ static void mpc512x_psc_spi_deactivate_cs(struct spi_device *spi)
 {
        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 @@ static int mpc512x_psc_spi_setup(struct spi_device *spi)
        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 @@ static int mpc512x_psc_spi_setup(struct spi_device *spi)
                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 int mpc512x_psc_spi_transfer(struct spi_device *spi,
 
 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 @@ static irqreturn_t mpc512x_psc_spi_isr(int irq, void *dev_id)
        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 @@ static int mpc512x_psc_spi_do_probe(struct device *dev, u32 regaddr,
        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;