[PATCH 3/3] mfd: stmfx: disable irq in suspend to avoid spurious interrupt

From: Amelie Delaunay
Date: Wed Apr 22 2020 - 05:08:53 EST


When STMFX supply is stopped, spurious interrupt can occur. To avoid that,
disable the interrupt in suspend before disabling the regulator and
re-enable it at the end of resume.

Fixes: 06252ade9156 ("mfd: Add ST Multi-Function eXpander (STMFX) core driver")
Signed-off-by: Amelie Delaunay <amelie.delaunay@xxxxxx>
---
drivers/mfd/stmfx.c | 6 ++++++
include/linux/mfd/stmfx.h | 1 +
2 files changed, 7 insertions(+)

diff --git a/drivers/mfd/stmfx.c b/drivers/mfd/stmfx.c
index 1977fe95f876..711979afd90a 100644
--- a/drivers/mfd/stmfx.c
+++ b/drivers/mfd/stmfx.c
@@ -296,6 +296,8 @@ static int stmfx_irq_init(struct i2c_client *client)
if (ret)
goto irq_exit;

+ stmfx->irq = client->irq;
+
return 0;

irq_exit:
@@ -486,6 +488,8 @@ static int stmfx_suspend(struct device *dev)
if (ret)
return ret;

+ disable_irq(stmfx->irq);
+
if (stmfx->vdd)
return regulator_disable(stmfx->vdd);

@@ -529,6 +533,8 @@ static int stmfx_resume(struct device *dev)
if (ret)
return ret;

+ enable_irq(stmfx->irq);
+
return 0;
}
#endif
diff --git a/include/linux/mfd/stmfx.h b/include/linux/mfd/stmfx.h
index 3c67983678ec..744dce63946e 100644
--- a/include/linux/mfd/stmfx.h
+++ b/include/linux/mfd/stmfx.h
@@ -109,6 +109,7 @@ struct stmfx {
struct device *dev;
struct regmap *map;
struct regulator *vdd;
+ int irq;
struct irq_domain *irq_domain;
struct mutex lock; /* IRQ bus lock */
u8 irq_src;
--
2.17.1