gpio: mpc8xxx: Add ls1028a device specify function.

There is a device specify register(named GPIO_IBE)
on ls1028a need to enable in initial stage.

Signed-off-by: Song Hui <hui.song_1@nxp.com>
Link: https://lore.kernel.org/r/20190718094902.15562-2-hui.song_1@nxp.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 31 insertions, 0 deletions

diff --git a/drivers/gpio/gpio-mpc8xxx.c b/drivers/gpio/gpio-mpc8xxx.c
index c8673a5d9412..1a680aa28769 100644
--- a/drivers/gpio/gpio-mpc8xxx.c
+++ b/drivers/gpio/gpio-mpc8xxx.c
@@ -32,6 +32,7 @@
 #define GPIO_IMR                0x10
 #define GPIO_ICR                0x14
 #define GPIO_ICR2               0x18
+#define GPIO_IBE                0x18
 
 struct mpc8xxx_gpio_chip {
         struct gpio_chip        gc;
@@ -45,6 +46,27 @@ struct mpc8xxx_gpio_chip {
         unsigned int irqn;
 };
 
+/* The GPIO Input Buffer Enable register(GPIO_IBE) is used to
+ * control the input enable of each individual GPIO port.
+ * When an individual GPIO port’s direction is set to
+ * input (GPIO_GPDIR[DRn=0]), the associated input enable must be
+ * set (GPIOxGPIE[IEn]=1) to propagate the port value to the GPIO
+ * Data Register.
+ */
+static int ls1028a_gpio_dir_in_init(struct gpio_chip *gc)
+{
+        unsigned long flags;
+        struct mpc8xxx_gpio_chip *mpc8xxx_gc = gpiochip_get_data(gc);
+
+        spin_lock_irqsave(&gc->bgpio_lock, flags);
+
+        gc->write_reg(mpc8xxx_gc->regs + GPIO_IBE, 0xffffffff);
+
+        spin_unlock_irqrestore(&gc->bgpio_lock, flags);
+
+        return 0;
+}
+
 /*
  * This hardware has a big endian bit assignment such that GPIO line 0 is
  * connected to bit 31, line 1 to bit 30 ... line 31 to bit 0.
@@ -261,6 +283,7 @@ static const struct irq_domain_ops mpc8xxx_gpio_irq_ops = {
 };
 
 struct mpc8xxx_gpio_devtype {
+        int (*gpio_dir_in_init)(struct gpio_chip *chip);
         int (*gpio_dir_out)(struct gpio_chip *, unsigned int, int);
         int (*gpio_get)(struct gpio_chip *, unsigned int);
         int (*irq_set_type)(struct irq_data *, unsigned int);
@@ -271,6 +294,10 @@ static const struct mpc8xxx_gpio_devtype mpc512x_gpio_devtype = {
         .irq_set_type = mpc512x_irq_set_type,
 };
 
+static const struct mpc8xxx_gpio_devtype ls1028a_gpio_devtype = {
+        .gpio_dir_in_init = ls1028a_gpio_dir_in_init,
+};
+
 static const struct mpc8xxx_gpio_devtype mpc5125_gpio_devtype = {
         .gpio_dir_out = mpc5125_gpio_dir_out,
         .irq_set_type = mpc512x_irq_set_type,
@@ -291,6 +318,7 @@ static const struct of_device_id mpc8xxx_gpio_ids[] = {
         { .compatible = "fsl,mpc5121-gpio", .data = &mpc512x_gpio_devtype, },
         { .compatible = "fsl,mpc5125-gpio", .data = &mpc5125_gpio_devtype, },
         { .compatible = "fsl,pq3-gpio",     },
+        { .compatible = "fsl,ls1028a-gpio", .data = &ls1028a_gpio_devtype, },
         { .compatible = "fsl,qoriq-gpio",   },
         {}
 };
@@ -376,6 +404,9 @@ static int mpc8xxx_probe(struct platform_device *pdev)
         /* ack and mask all irqs */
         gc->write_reg(mpc8xxx_gc->regs + GPIO_IER, 0xffffffff);
         gc->write_reg(mpc8xxx_gc->regs + GPIO_IMR, 0);
+        /* enable input buffer  */
+        if (devtype->gpio_dir_in_init)
+                devtype->gpio_dir_in_init(gc);
 
         irq_set_chained_handler_and_data(mpc8xxx_gc->irqn,
                                          mpc8xxx_gpio_irq_cascade, mpc8xxx_gc);