plat-nomadik: add custom dbg_show for GPIO

Signed-off-by: Rabin Vincent <rabin.vincent@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

1 files changed, 92 insertions, 0 deletions

diff --git a/arch/arm/plat-nomadik/gpio.c b/arch/arm/plat-nomadik/gpio.c
index 30bb92a746e1..5b5fd1ee3c04 100644
--- a/arch/arm/plat-nomadik/gpio.c
+++ b/arch/arm/plat-nomadik/gpio.c
@@ -604,6 +604,97 @@ static int nmk_gpio_to_irq(struct gpio_chip *chip, unsigned offset)
         return NOMADIK_GPIO_TO_IRQ(nmk_chip->chip.base) + offset;
 }
 
+#ifdef CONFIG_DEBUG_FS
+
+#include <linux/seq_file.h>
+
+static void nmk_gpio_dbg_show(struct seq_file *s, struct gpio_chip *chip)
+{
+        int mode;
+        unsigned                i;
+        unsigned                gpio = chip->base;
+        int                     is_out;
+        struct nmk_gpio_chip *nmk_chip =
+                container_of(chip, struct nmk_gpio_chip, chip);
+        const char *modes[] = {
+                [NMK_GPIO_ALT_GPIO]     = "gpio",
+                [NMK_GPIO_ALT_A]        = "altA",
+                [NMK_GPIO_ALT_B]        = "altB",
+                [NMK_GPIO_ALT_C]        = "altC",
+        };
+
+        for (i = 0; i < chip->ngpio; i++, gpio++) {
+                const char *label = gpiochip_is_requested(chip, i);
+                bool pull;
+                u32 bit = 1 << i;
+
+                if (!label)
+                        continue;
+
+                is_out = readl(nmk_chip->addr + NMK_GPIO_DIR) & bit;
+                pull = !(readl(nmk_chip->addr + NMK_GPIO_PDIS) & bit);
+                mode = nmk_gpio_get_mode(gpio);
+                seq_printf(s, " gpio-%-3d (%-20.20s) %s %s %s %s",
+                        gpio, label,
+                        is_out ? "out" : "in ",
+                        chip->get
+                                ? (chip->get(chip, i) ? "hi" : "lo")
+                                : "?  ",
+                        (mode < 0) ? "unknown" : modes[mode],
+                        pull ? "pull" : "none");
+
+                if (!is_out) {
+                        int             irq = gpio_to_irq(gpio);
+                        struct irq_desc *desc = irq_to_desc(irq);
+
+                        /* This races with request_irq(), set_irq_type(),
+                         * and set_irq_wake() ... but those are "rare".
+                         *
+                         * More significantly, trigger type flags aren't
+                         * currently maintained by genirq.
+                         */
+                        if (irq >= 0 && desc->action) {
+                                char *trigger;
+
+                                switch (desc->status & IRQ_TYPE_SENSE_MASK) {
+                                case IRQ_TYPE_NONE:
+                                        trigger = "(default)";
+                                        break;
+                                case IRQ_TYPE_EDGE_FALLING:
+                                        trigger = "edge-falling";
+                                        break;
+                                case IRQ_TYPE_EDGE_RISING:
+                                        trigger = "edge-rising";
+                                        break;
+                                case IRQ_TYPE_EDGE_BOTH:
+                                        trigger = "edge-both";
+                                        break;
+                                case IRQ_TYPE_LEVEL_HIGH:
+                                        trigger = "level-high";
+                                        break;
+                                case IRQ_TYPE_LEVEL_LOW:
+                                        trigger = "level-low";
+                                        break;
+                                default:
+                                        trigger = "?trigger?";
+                                        break;
+                                }
+
+                                seq_printf(s, " irq-%d %s%s",
+                                        irq, trigger,
+                                        (desc->status & IRQ_WAKEUP)
+                                                ? " wakeup" : "");
+                        }
+                }
+
+                seq_printf(s, "\n");
+        }
+}
+
+#else
+#define nmk_gpio_dbg_show       NULL
+#endif
+
 /* This structure is replicated for each GPIO block allocated at probe time */
 static struct gpio_chip nmk_gpio_template = {
         .direction_input        = nmk_gpio_make_input,
@@ -611,6 +702,7 @@ static struct gpio_chip nmk_gpio_template = {
         .direction_output       = nmk_gpio_make_output,
         .set                    = nmk_gpio_set_output,
         .to_irq                 = nmk_gpio_to_irq,
+        .dbg_show               = nmk_gpio_dbg_show,
         .can_sleep              = 0,
 };