max8907c mfd: Add wake irq capability

This change allows the max8907c to wake the system when receiving an
irq.  It also masks all non-wake conditions from causing an irq when
going into suspend and unmasks these conditions when resuming to not
cause spurious wake-up events.

Change-Id: I5eadb929ff4aded8a6ec11426ab424f0f692c042
Reviewed-on: http://git-master/r/20100
Tested-by: Thomas Cherry <tcherry@nvidia.com>
Reviewed-by: Sachin Nikam <snikam@nvidia.com>
Reviewed-by: Bharat Nihalani <bnihalani@nvidia.com>

diff --git a/drivers/mfd/max8907c-irq.c b/drivers/mfd/max8907c-irq.c
index e9773c0fe00e5f64eb40188bbe80bf97b8dec6b4..c018e6601f67bcbbcd82c227cebb79fa1676c5e7 100644 (file)
--- a/drivers/mfd/max8907c-irq.c
+++ b/drivers/mfd/max8907c-irq.c
@@ -24,6 +24,7 @@ struct max8907c_irq_data {
        int     enable;         /* enable or not */
        int     offs;           /* bit offset in mask register */
        bool    is_rtc;
+       int     wake;
 };
 
 static struct max8907c_irq_data max8907c_irqs[] = {
@@ -190,19 +191,12 @@ static void max8907c_irq_sync_unlock(unsigned int irq)
 {
        struct max8907c *chip = get_irq_chip_data(irq);
        struct max8907c_irq_data *irq_data;
-       static unsigned char cache_chg[2] = {0xff, 0xff};
-       static unsigned char cache_on[2] = {0xff, 0xff};
-       static unsigned char cache_rtc = 0xff;
        unsigned char irq_chg[2], irq_on[2];
        unsigned char irq_rtc;
        int i;
 
-       /* Load cached value. In initial, all IRQs are masked */
-       irq_chg[0] = cache_chg[0];
-       irq_chg[1] = cache_chg[1];
-       irq_on[0] = cache_on[0];
-       irq_on[1] = cache_on[1];
-       irq_rtc = cache_rtc;
+       irq_chg[0] = irq_chg[1] = irq_on[0] = irq_on[1] = irq_rtc = 0xFF;
+
        for (i = 0; i < ARRAY_SIZE(max8907c_irqs); i++) {
                irq_data = &max8907c_irqs[i];
                /* 1 -- disable, 0 -- enable */
@@ -228,28 +222,28 @@ static void max8907c_irq_sync_unlock(unsigned int irq)
                }
        }
        /* update mask into registers */
-       if (cache_chg[0] != irq_chg[0]) {
-               cache_chg[0] = irq_chg[0];
+       if (chip->cache_chg[0] != irq_chg[0]) {
+               chip->cache_chg[0] = irq_chg[0];
                max8907c_reg_write(chip->i2c_power, MAX8907C_REG_CHG_IRQ1_MASK,
                        irq_chg[0]);
        }
-       if (cache_chg[1] != irq_chg[1]) {
-               cache_chg[1] = irq_chg[1];
+       if (chip->cache_chg[1] != irq_chg[1]) {
+               chip->cache_chg[1] = irq_chg[1];
                max8907c_reg_write(chip->i2c_power, MAX8907C_REG_CHG_IRQ2_MASK,
                        irq_chg[1]);
        }
-       if (cache_on[0] != irq_on[0]) {
-               cache_on[0] = irq_on[0];
+       if (chip->cache_on[0] != irq_on[0]) {
+               chip->cache_on[0] = irq_on[0];
                max8907c_reg_write(chip->i2c_power, MAX8907C_REG_ON_OFF_IRQ1_MASK,
                                irq_on[0]);
        }
-       if (cache_on[1] != irq_on[1]) {
-               cache_on[1] = irq_on[1];
+       if (chip->cache_on[1] != irq_on[1]) {
+               chip->cache_on[1] = irq_on[1];
                max8907c_reg_write(chip->i2c_power, MAX8907C_REG_ON_OFF_IRQ2_MASK,
                                irq_on[1]);
        }
-       if (cache_rtc != irq_rtc) {
-               cache_rtc = irq_rtc;
+       if (chip->cache_rtc != irq_rtc) {
+               chip->cache_rtc = irq_rtc;
                max8907c_reg_write(chip->i2c_rtc, MAX8907C_REG_RTC_IRQ_MASK,
                                   irq_rtc);
        }
@@ -270,12 +264,25 @@ static void max8907c_irq_disable(unsigned int irq)
        max8907c_irqs[irq - chip->irq_base].enable = 0;
 }
 
+static int max8907c_irq_set_wake(unsigned int irq, unsigned int on)
+{
+       struct max8907c *chip = get_irq_chip_data(irq);
+       if (on) {
+               max8907c_irqs[irq - chip->irq_base].wake
+                       = max8907c_irqs[irq - chip->irq_base].enable;
+       } else {
+               max8907c_irqs[irq - chip->irq_base].wake = 0;
+       }
+       return 0;
+}
+
 static struct irq_chip max8907c_irq_chip = {
        .name           = "max8907c",
        .bus_lock       = max8907c_irq_lock,
        .bus_sync_unlock = max8907c_irq_sync_unlock,
        .enable         = max8907c_irq_enable,
        .disable        = max8907c_irq_disable,
+       .set_wake       = max8907c_irq_set_wake,
 };
 
 int max8907c_irq_init(struct max8907c *chip, int irq, int irq_base)
@@ -304,6 +311,10 @@ int max8907c_irq_init(struct max8907c *chip, int irq, int irq_base)
        max8907c_reg_write(chip->i2c_power, MAX8907C_REG_ON_OFF_IRQ2_MASK, 0xff);
        max8907c_reg_write(chip->i2c_rtc, MAX8907C_REG_RTC_IRQ_MASK, 0xff);
 
+       chip->cache_chg[0] = chip->cache_chg[1] =
+               chip->cache_on[0] = chip->cache_on[1] =
+               chip->cache_rtc = 0xFF;
+
        mutex_init(&chip->irq_lock);
        chip->core_irq = irq;
        chip->irq_base = irq_base;
@@ -330,23 +341,75 @@ int max8907c_irq_init(struct max8907c *chip, int irq, int irq_base)
                chip->core_irq = 0;
        }
 
+       device_init_wakeup(chip->dev, 1);
+
        return ret;
 }
 
 int max8907c_suspend(struct i2c_client *i2c, pm_message_t state)
 {
-       struct max8907c *max8907c = i2c_get_clientdata(i2c);
+       struct max8907c *chip = i2c_get_clientdata(i2c);
 
-       disable_irq(max8907c->core_irq);
+       struct max8907c_irq_data *irq_data;
+       unsigned char irq_chg[2], irq_on[2];
+       unsigned char irq_rtc;
+       int i;
+
+       irq_chg[0] = irq_chg[1] = irq_on[0] = irq_on[1] = irq_rtc = 0xFF;
+
+       for (i = 0; i < ARRAY_SIZE(max8907c_irqs); i++) {
+               irq_data = &max8907c_irqs[i];
+               /* 1 -- disable, 0 -- enable */
+               switch (irq_data->mask_reg) {
+               case MAX8907C_REG_CHG_IRQ1_MASK:
+                       irq_chg[0] &= ~irq_data->wake;
+                       break;
+               case MAX8907C_REG_CHG_IRQ2_MASK:
+                       irq_chg[1] &= ~irq_data->wake;
+                       break;
+               case MAX8907C_REG_ON_OFF_IRQ1_MASK:
+                       irq_on[0] &= ~irq_data->wake;
+                       break;
+               case MAX8907C_REG_ON_OFF_IRQ2_MASK:
+                       irq_on[1] &= ~irq_data->wake;
+                       break;
+               case MAX8907C_REG_RTC_IRQ_MASK:
+                       irq_rtc &= ~irq_data->wake;
+                       break;
+               default:
+                       dev_err(chip->dev, "wrong IRQ\n");
+                       break;
+               }
+       }
+
+       max8907c_reg_write(chip->i2c_power, MAX8907C_REG_CHG_IRQ1_MASK, irq_chg[0]);
+       max8907c_reg_write(chip->i2c_power, MAX8907C_REG_CHG_IRQ2_MASK, irq_chg[1]);
+       max8907c_reg_write(chip->i2c_power, MAX8907C_REG_ON_OFF_IRQ1_MASK, irq_on[0]);
+       max8907c_reg_write(chip->i2c_power, MAX8907C_REG_ON_OFF_IRQ2_MASK, irq_on[1]);
+       max8907c_reg_write(chip->i2c_rtc, MAX8907C_REG_RTC_IRQ_MASK, irq_rtc);
+
+       if (device_may_wakeup(chip->dev))
+               enable_irq_wake(chip->core_irq);
+       else
+               disable_irq(chip->core_irq);
 
        return 0;
 }
 
 int max8907c_resume(struct i2c_client *i2c)
 {
-       struct max8907c *max8907c = i2c_get_clientdata(i2c);
+       struct max8907c *chip = i2c_get_clientdata(i2c);
+
+       if (device_may_wakeup(chip->dev))
+               disable_irq_wake(chip->core_irq);
+       else
+               enable_irq(chip->core_irq);
 
-       enable_irq(max8907c->core_irq);
+       max8907c_reg_write(chip->i2c_power, MAX8907C_REG_CHG_IRQ1_MASK, chip->cache_chg[0]);
+       max8907c_reg_write(chip->i2c_power, MAX8907C_REG_CHG_IRQ2_MASK, chip->cache_chg[1]);
+       max8907c_reg_write(chip->i2c_power, MAX8907C_REG_ON_OFF_IRQ1_MASK, chip->cache_on[0]);
+       max8907c_reg_write(chip->i2c_power, MAX8907C_REG_ON_OFF_IRQ2_MASK, chip->cache_on[1]);
+       max8907c_reg_write(chip->i2c_rtc, MAX8907C_REG_RTC_IRQ_MASK, chip->cache_rtc);
 
        return 0;
 }

diff --git a/include/linux/mfd/max8907c.h b/include/linux/mfd/max8907c.h
index d4d62d4a64216a9a73e915d1ba80bc1455d6f9c1..d77ac500da29a29b9723593b1ab16269e45f0b58 100644 (file)
--- a/include/linux/mfd/max8907c.h
+++ b/include/linux/mfd/max8907c.h
@@ -200,6 +200,11 @@ struct max8907c {
        struct i2c_client       *i2c_rtc;
        int                     irq_base;
        int                     core_irq;
+
+       unsigned char           cache_chg[2];
+       unsigned char           cache_on[2];
+       unsigned char           cache_rtc;
+
 };
 
 struct max8907c_platform_data {