gpio: dwapb: Call directly into the gpiochip to read value

We were going out through the (legacy) gpio API to read the value
of a line to set up polarity inversion. This is abusive. Do something
less abusive by looking up the actual struct gpio_chip *
instance and calling .get() directly on it.

Acked-by: Hoan Tran <hotran@apm.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/gpio/gpio-dwapb.c b/drivers/gpio/gpio-dwapb.c
index 677988f2136906e6caa7f301470d48a957d9d1be..b0704a8835130e0d84c62fc22cb2bcdfea1d4c12 100644 (file)
--- a/drivers/gpio/gpio-dwapb.c
+++ b/drivers/gpio/gpio-dwapb.c
@@ -9,8 +9,6 @@
  */
 #include <linux/acpi.h>
 #include <linux/gpio/driver.h>
-/* FIXME: for gpio_get_value(), replace this with direct register read */
-#include <linux/gpio.h>
 #include <linux/err.h>
 #include <linux/init.h>
 #include <linux/interrupt.h>
@@ -153,16 +151,40 @@ static int dwapb_gpio_to_irq(struct gpio_chip *gc, unsigned offset)
        return irq_find_mapping(gpio->domain, offset);
 }
 
+static struct dwapb_gpio_port *dwapb_offs_to_port(struct dwapb_gpio *gpio, unsigned int offs)
+{
+       struct dwapb_gpio_port *port;
+       int i;
+
+       for (i = 0; i < gpio->nr_ports; i++) {
+               port = &gpio->ports[i];
+               if (port->idx == offs / 32)
+                       return port;
+       }
+
+       return NULL;
+}
+
 static void dwapb_toggle_trigger(struct dwapb_gpio *gpio, unsigned int offs)
 {
-       u32 v = dwapb_read(gpio, GPIO_INT_POLARITY);
+       struct dwapb_gpio_port *port = dwapb_offs_to_port(gpio, offs);
+       struct gpio_chip *gc;
+       u32 pol;
+       int val;
+
+       if (!port)
+               return;
+       gc = &port->gc;
 
-       if (gpio_get_value(gpio->ports[0].gc.base + offs))
-               v &= ~BIT(offs);
+       pol = dwapb_read(gpio, GPIO_INT_POLARITY);
+       /* Just read the current value right out of the data register */
+       val = gc->get(gc, offs % 32);
+       if (val)
+               pol &= ~BIT(offs);
        else
-               v |= BIT(offs);
+               pol |= BIT(offs);
 
-       dwapb_write(gpio, GPIO_INT_POLARITY, v);
+       dwapb_write(gpio, GPIO_INT_POLARITY, pol);
 }
 
 static u32 dwapb_do_irq(struct dwapb_gpio *gpio)
@@ -481,6 +503,7 @@ static int dwapb_gpio_add_port(struct dwapb_gpio *gpio,
        dirout = gpio->regs + GPIO_SWPORTA_DDR +
                (pp->idx * GPIO_SWPORT_DDR_STRIDE);
 
+       /* This registers 32 GPIO lines per port */
        err = bgpio_init(&port->gc, gpio->dev, 4, dat, set, NULL, dirout,
                         NULL, 0);
        if (err) {