[ARM] 4768/2: ixp4xx: Button and LED updates for the nas100d board

[firefly-linux-kernel-4.4.55.git] / arch / arm / mach-ixp4xx / nas100d-power.c

diff --git a/arch/arm/mach-ixp4xx/nas100d-power.c b/arch/arm/mach-ixp4xx/nas100d-power.c
index 29aa98d3a7faeb4993213e29aee093fe0f389f88..4c1c01bb3fe20ef3310bb85790ac9ed6f4c2caea 100644 (file)
--- a/arch/arm/mach-ixp4xx/nas100d-power.c
+++ b/arch/arm/mach-ixp4xx/nas100d-power.c
@@ -21,15 +21,59 @@
 #include <linux/irq.h>
 #include <linux/module.h>
 #include <linux/reboot.h>
+#include <linux/jiffies.h>
+#include <linux/timer.h>
 
+#include <asm/gpio.h>
 #include <asm/mach-types.h>
 
-static irqreturn_t nas100d_reset_handler(int irq, void *dev_id)
+/* This is used to make sure the power-button pusher is serious.  The button
+ * must be held until the value of this counter reaches zero.
+ */
+static int power_button_countdown;
+
+/* Must hold the button down for at least this many counts to be processed */
+#define PBUTTON_HOLDDOWN_COUNT 4 /* 2 secs */
+
+static void nas100d_power_handler(unsigned long data);
+static DEFINE_TIMER(nas100d_power_timer, nas100d_power_handler, 0, 0);
+
+static void nas100d_power_handler(unsigned long data)
 {
-       /* Signal init to do the ctrlaltdel action, this will bypass init if
-        * it hasn't started and do a kernel_restart.
+       /* This routine is called twice per second to check the
+        * state of the power button.
         */
-       ctrl_alt_del();
+
+       if (gpio_get_value(NAS100D_PB_GPIO)) {
+
+               /* IO Pin is 1 (button pushed) */
+               if (power_button_countdown > 0)
+                       power_button_countdown--;
+
+       } else {
+
+               /* Done on button release, to allow for auto-power-on mods. */
+               if (power_button_countdown == 0) {
+                       /* Signal init to do the ctrlaltdel action,
+                        * this will bypass init if it hasn't started
+                        * and do a kernel_restart.
+                        */
+                       ctrl_alt_del();
+
+                       /* Change the state of the power LED to "blink" */
+                       gpio_line_set(NAS100D_LED_PWR_GPIO, IXP4XX_GPIO_LOW);
+               } else {
+                       power_button_countdown = PBUTTON_HOLDDOWN_COUNT;
+               }
+       }
+
+       mod_timer(&nas100d_power_timer, jiffies + msecs_to_jiffies(500));
+}
+
+static irqreturn_t nas100d_reset_handler(int irq, void *dev_id)
+{
+       /* This is the paper-clip reset, it shuts the machine down directly. */
+       machine_power_off();
 
        return IRQ_HANDLED;
 }
@@ -39,17 +83,30 @@ static int __init nas100d_power_init(void)
        if (!(machine_is_nas100d()))
                return 0;
 
-       set_irq_type(NAS100D_RB_IRQ, IRQT_LOW);
+       set_irq_type(gpio_to_irq(NAS100D_RB_GPIO), IRQT_LOW);
 
-       if (request_irq(NAS100D_RB_IRQ, &nas100d_reset_handler,
+       if (request_irq(gpio_to_irq(NAS100D_RB_GPIO), &nas100d_reset_handler,
                IRQF_DISABLED, "NAS100D reset button", NULL) < 0) {
 
                printk(KERN_DEBUG "Reset Button IRQ %d not available\n",
-                       NAS100D_RB_IRQ);
+                       gpio_to_irq(NAS100D_RB_GPIO));
 
                return -EIO;
        }
 
+       /* The power button on the Iomega NAS100d is on GPIO 14, but
+        * it cannot handle interrupts on that GPIO line.  So we'll
+        * have to poll it with a kernel timer.
+        */
+
+       /* Make sure that the power button GPIO is set up as an input */
+       gpio_line_config(NAS100D_PB_GPIO, IXP4XX_GPIO_IN);
+
+       /* Set the initial value for the power button IRQ handler */
+       power_button_countdown = PBUTTON_HOLDDOWN_COUNT;
+
+       mod_timer(&nas100d_power_timer, jiffies + msecs_to_jiffies(500));
+
        return 0;
 }
 
@@ -58,7 +115,9 @@ static void __exit nas100d_power_exit(void)
        if (!(machine_is_nas100d()))
                return;
 
-       free_irq(NAS100D_RB_IRQ, NULL);
+       del_timer_sync(&nas100d_power_timer);
+
+       free_irq(gpio_to_irq(NAS100D_RB_GPIO), NULL);
 }
 
 module_init(nas100d_power_init);