mfd: pm8921: Implement irq_get_irqchip_state

Implement irq_chip->irq_get_irqchip_state to make it possible for PMIC
block drivers to access the IRQ real time status bits. The status bits
are used for various kinds of input signals, e.g. GPIO.

Signed-off-by: Bjorn Andersson <bjorn.andersson@sonymobile.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/mfd/pm8921-core.c

@@ -236,11 +236,49 @@ static int pm8xxx_irq_set_type(struct irq_data *d, unsigned int flow_type)
 	return pm8xxx_config_irq(chip, block, config);
 }
 
+static int pm8xxx_irq_get_irqchip_state(struct irq_data *d,
+					enum irqchip_irq_state which,
+					bool *state)
+{
+	struct pm_irq_chip *chip = irq_data_get_irq_chip_data(d);
+	unsigned int pmirq = irqd_to_hwirq(d);
+	unsigned int bits;
+	int irq_bit;
+	u8 block;
+	int rc;
+
+	if (which != IRQCHIP_STATE_LINE_LEVEL)
+		return -EINVAL;
+
+	block = pmirq / 8;
+	irq_bit = pmirq % 8;
+
+	spin_lock(&chip->pm_irq_lock);
+	rc = regmap_write(chip->regmap, SSBI_REG_ADDR_IRQ_BLK_SEL, block);
+	if (rc) {
+		pr_err("Failed Selecting Block %d rc=%d\n", block, rc);
+		goto bail;
+	}
+
+	rc = regmap_read(chip->regmap, SSBI_REG_ADDR_IRQ_RT_STATUS, &bits);
+	if (rc) {
+		pr_err("Failed Reading Status rc=%d\n", rc);
+		goto bail;
+	}
+
+	*state = !!(bits & BIT(irq_bit));
+bail:
+	spin_unlock(&chip->pm_irq_lock);
+
+	return rc;
+}
+
 static struct irq_chip pm8xxx_irq_chip = {
 	.name		= "pm8xxx",
 	.irq_mask_ack	= pm8xxx_irq_mask_ack,
 	.irq_unmask	= pm8xxx_irq_unmask,
 	.irq_set_type	= pm8xxx_irq_set_type,
+	.irq_get_irqchip_state = pm8xxx_irq_get_irqchip_state,
 	.flags		= IRQCHIP_MASK_ON_SUSPEND | IRQCHIP_SKIP_SET_WAKE,
 };