[PATCH fixes 2/2] extcon: max77693: Fix always masked MUIC interrupts

[Krzysztof Kozlowski <k.kozlowski@samsung.com>]

All interrupts coming from MUIC were ignored because interrupt source
register was masked.

The Maxim 77693 has a "interrupt source" - a separate register and interrupts
which give information about PMIC block triggering the individual
interrupt (charger, topsys, MUIC, flash LED).

By default bootloader could initialize this register to "mask all"
value. In such case (observed on Trats2 board) MUIC interrupts won't be
generated regardless of their mask status. Regmap irq chip was unmasking
individual MUIC interrupts but the source was masked

Before introducing regmap irq chip this interrupt source was unmasked,
read and acked. Reading and acking is not necessary but unmasking is. Do
it in extcon driver.

Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Cc: <stable@vger.kernel.org>
Fixes: 342d669c1ee4 ("mfd: max77693: Handle IRQs using regmap")
---
 drivers/extcon/extcon-max77693.c     | 16 ++++++++++++++++
 include/linux/mfd/max77693-private.h |  5 +++++
 2 files changed, 21 insertions(+)

diff --git a/drivers/extcon/extcon-max77693.c b/drivers/extcon/extcon-max77693.c
index 490e27475bac..d3adacf3187f 100644
--- a/drivers/extcon/extcon-max77693.c
+++ b/drivers/extcon/extcon-max77693.c
@@ -1176,6 +1176,22 @@ static int max77693_muic_probe(struct platform_device *pdev)
 		}
 	}
 
+	if (i) {
+		/*
+		 * i>0, at least one MUIC interrupt requested so need to unmask
+		 * MUIC interrupt in INTSRC register. Without that MUIC
+		 * interrupts will not be reported.
+		 */
+		ret = regmap_update_bits(max77693->regmap,
+				MAX77693_PMIC_REG_INTSRC_MASK, SRC_IRQ_MUIC,
+				~SRC_IRQ_MUIC);
+		if (ret < 0) {
+			dev_err(&pdev->dev, "Could not unmask MUIC interrupt in INTSRC: %d\n",
+					ret);
+			return ret;
+		}
+	}
+
 	/* Initialize extcon device */
 	info->edev = devm_extcon_dev_allocate(&pdev->dev,
 					      max77693_extcon_cable);
diff --git a/include/linux/mfd/max77693-private.h b/include/linux/mfd/max77693-private.h
index e1b2b61285b9..4f1a80b66ecf 100644
--- a/include/linux/mfd/max77693-private.h
+++ b/include/linux/mfd/max77693-private.h
@@ -438,6 +438,11 @@ enum max77693_irq_source {
 	MAX77693_IRQ_GROUP_NR,
 };
 
+#define SRC_IRQ_CHARGER			BIT(0)
+#define SRC_IRQ_TOP			BIT(1)
+#define SRC_IRQ_FLASH			BIT(2)
+#define SRC_IRQ_MUIC			BIT(3)
+
 #define LED_IRQ_FLED2_OPEN		BIT(0)
 #define LED_IRQ_FLED2_SHORT		BIT(1)
 #define LED_IRQ_FLED1_OPEN		BIT(2)
-- 
1.9.1