mfd: Clear twl6030 IRQ status register only once
[linux-flexiantxendom0.git] / drivers / mfd / twl6030-irq.c
index 3b9c775..83f4988 100644 (file)
  */
 
 #include <linux/init.h>
+#include <linux/export.h>
 #include <linux/interrupt.h>
 #include <linux/irq.h>
 #include <linux/kthread.h>
 #include <linux/i2c/twl.h>
 #include <linux/platform_device.h>
+#include <linux/suspend.h>
 
 #include "twl-core.h"
 
@@ -76,15 +78,55 @@ static int twl6030_interrupt_mapping[24] = {
        USBOTG_INTR_OFFSET,     /* Bit 18       ID                      */
        USB_PRES_INTR_OFFSET,   /* Bit 19       VBUS                    */
        CHARGER_INTR_OFFSET,    /* Bit 20       CHRG_CTRL               */
-       CHARGER_INTR_OFFSET,    /* Bit 21       EXT_CHRG                */
-       CHARGER_INTR_OFFSET,    /* Bit 22       INT_CHRG                */
+       CHARGERFAULT_INTR_OFFSET,       /* Bit 21       EXT_CHRG        */
+       CHARGERFAULT_INTR_OFFSET,       /* Bit 22       INT_CHRG        */
        RSV_INTR_OFFSET,        /* Bit 23       Reserved                */
 };
 /*----------------------------------------------------------------------*/
 
 static unsigned twl6030_irq_base;
+static int twl_irq;
+static bool twl_irq_wake_enabled;
 
 static struct completion irq_event;
+static atomic_t twl6030_wakeirqs = ATOMIC_INIT(0);
+
+static int twl6030_irq_pm_notifier(struct notifier_block *notifier,
+                                  unsigned long pm_event, void *unused)
+{
+       int chained_wakeups;
+
+       switch (pm_event) {
+       case PM_SUSPEND_PREPARE:
+               chained_wakeups = atomic_read(&twl6030_wakeirqs);
+
+               if (chained_wakeups && !twl_irq_wake_enabled) {
+                       if (enable_irq_wake(twl_irq))
+                               pr_err("twl6030 IRQ wake enable failed\n");
+                       else
+                               twl_irq_wake_enabled = true;
+               } else if (!chained_wakeups && twl_irq_wake_enabled) {
+                       disable_irq_wake(twl_irq);
+                       twl_irq_wake_enabled = false;
+               }
+
+               disable_irq(twl_irq);
+               break;
+
+       case PM_POST_SUSPEND:
+               enable_irq(twl_irq);
+               break;
+
+       default:
+               break;
+       }
+
+       return NOTIFY_DONE;
+}
+
+static struct notifier_block twl6030_irq_pm_notifier_block = {
+       .notifier_call = twl6030_irq_pm_notifier,
+};
 
 /*
  * This thread processes interrupts reported by the Primary Interrupt Handler.
@@ -145,8 +187,17 @@ static int twl6030_irq_thread(void *data)
                        }
                local_irq_enable();
                }
-               ret = twl_i2c_write(TWL_MODULE_PIH, sts.bytes,
-                               REG_INT_STS_A, 3); /* clear INT_STS_A */
+
+               /*
+                * NOTE:
+                * Simulation confirms that documentation is wrong w.r.t the
+                * interrupt status clear operation. A single *byte* write to
+                * any one of STS_A to STS_C register results in all three
+                * STS registers being reset. Since it does not matter which
+                * value is written, all three registers are cleared on a
+                * single byte write, so we just use 0x0 to clear.
+                */
+               ret = twl_i2c_write_u8(TWL_MODULE_PIH, 0x00, REG_INT_STS_A);
                if (ret)
                        pr_warning("twl6030: I2C error in clearing PIH ISR\n");
 
@@ -183,10 +234,20 @@ static inline void activate_irq(int irq)
        set_irq_flags(irq, IRQF_VALID);
 #else
        /* same effect on other architectures */
-       set_irq_noprobe(irq);
+       irq_set_noprobe(irq);
 #endif
 }
 
+int twl6030_irq_set_wake(struct irq_data *d, unsigned int on)
+{
+       if (on)
+               atomic_inc(&twl6030_wakeirqs);
+       else
+               atomic_dec(&twl6030_wakeirqs);
+
+       return 0;
+}
+
 /*----------------------------------------------------------------------*/
 
 static unsigned twl6030_irq_next;
@@ -229,7 +290,7 @@ int twl6030_mmc_card_detect_config(void)
        twl6030_interrupt_unmask(TWL6030_MMCDETECT_INT_MASK,
                                                REG_INT_MSK_STS_B);
        /*
-        * Intially Configuring MMC_CTRL for receving interrupts &
+        * Initially Configuring MMC_CTRL for receiving interrupts &
         * Card status on TWL6030 for MMC1
         */
        ret = twl_i2c_read_u8(TWL6030_MODULE_ID0, &reg_val, TWL6030_MMCCTRL);
@@ -275,7 +336,7 @@ int twl6030_mmc_card_detect(struct device *dev, int slot)
                /* TWL6030 provide's Card detect support for
                 * only MMC1 controller.
                 */
-               pr_err("Unkown MMC controller %d in %s\n", pdev->id, __func__);
+               pr_err("Unknown MMC controller %d in %s\n", pdev->id, __func__);
                return ret;
        }
        /*
@@ -318,10 +379,12 @@ int twl6030_init_irq(int irq_num, unsigned irq_base, unsigned irq_end)
        twl6030_irq_chip = dummy_irq_chip;
        twl6030_irq_chip.name = "twl6030";
        twl6030_irq_chip.irq_set_type = NULL;
+       twl6030_irq_chip.irq_set_wake = twl6030_irq_set_wake;
 
        for (i = irq_base; i < irq_end; i++) {
-               set_irq_chip_and_handler(i, &twl6030_irq_chip,
-                               handle_simple_irq);
+               irq_set_chip_and_handler(i, &twl6030_irq_chip,
+                                        handle_simple_irq);
+               irq_set_chip_data(i, (void *)irq_num);
                activate_irq(i);
        }
 
@@ -331,6 +394,14 @@ int twl6030_init_irq(int irq_num, unsigned irq_base, unsigned irq_end)
 
        /* install an irq handler to demultiplex the TWL6030 interrupt */
        init_completion(&irq_event);
+
+       status = request_irq(irq_num, handle_twl6030_pih, 0,
+                               "TWL6030-PIH", &irq_event);
+       if (status < 0) {
+               pr_err("twl6030: could not claim irq%d: %d\n", irq_num, status);
+               goto fail_irq;
+       }
+
        task = kthread_run(twl6030_irq_thread, (void *)irq_num, "twl6030-irq");
        if (IS_ERR(task)) {
                pr_err("twl6030: could not create irq %d thread!\n", irq_num);
@@ -338,24 +409,22 @@ int twl6030_init_irq(int irq_num, unsigned irq_base, unsigned irq_end)
                goto fail_kthread;
        }
 
-       status = request_irq(irq_num, handle_twl6030_pih, IRQF_DISABLED,
-                               "TWL6030-PIH", &irq_event);
-       if (status < 0) {
-               pr_err("twl6030: could not claim irq%d: %d\n", irq_num, status);
-               goto fail_irq;
-       }
+       twl_irq = irq_num;
+       register_pm_notifier(&twl6030_irq_pm_notifier_block);
        return status;
-fail_irq:
-       free_irq(irq_num, &irq_event);
 
 fail_kthread:
+       free_irq(irq_num, &irq_event);
+
+fail_irq:
        for (i = irq_base; i < irq_end; i++)
-               set_irq_chip_and_handler(i, NULL, NULL);
+               irq_set_chip_and_handler(i, NULL, NULL);
        return status;
 }
 
 int twl6030_exit_irq(void)
 {
+       unregister_pm_notifier(&twl6030_irq_pm_notifier_block);
 
        if (twl6030_irq_base) {
                pr_err("twl6030: can't yet clean up IRQs?\n");