[PATCH] spmi: spmi-pmic-arb: Fix hw_irq overflow

[Subbaraman Narayanamurthy]

Currently, when handling the SPMI summary interrupt, the hw_irq
number is calculated based on SID, Peripheral ID, IRQ index and
APID. This is then passed to irq_find_mapping() to see if a
mapping exists for this hw_irq and if available, invoke the
interrupt handler. Since the IRQ index uses an "int" type, hw_irq
which is of unsigned long data type can take a large value when
SID has its MSB set to 1 and the type conversion happens. Because
of this, irq_find_mapping() returns 0 as there is no mapping
for this hw_irq. This ends up invoking cleanup_irq() as if
the interrupt is spurious whereas it is actually a valid
interrupt. Fix this by using the proper data type (u32) for id.

Signed-off-by: Subbaraman Narayanamurthy <subbaram@xxxxxxxxxxxxxx>
---
 drivers/spmi/spmi-pmic-arb.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/drivers/spmi/spmi-pmic-arb.c b/drivers/spmi/spmi-pmic-arb.c
index de844b4..bbbd311 100644
--- a/drivers/spmi/spmi-pmic-arb.c
+++ b/drivers/spmi/spmi-pmic-arb.c
@@ -1,6 +1,6 @@
 // SPDX-License-Identifier: GPL-2.0-only
 /*
- * Copyright (c) 2012-2015, 2017, The Linux Foundation. All rights reserved.
+ * Copyright (c) 2012-2015, 2017, 2021, The Linux Foundation. All rights reserved.
  */
 #include <linux/bitmap.h>
 #include <linux/delay.h>
@@ -505,8 +505,7 @@ static void cleanup_irq(struct spmi_pmic_arb *pmic_arb, u16 apid, int id)
 static void periph_interrupt(struct spmi_pmic_arb *pmic_arb, u16 apid)
 {
 	unsigned int irq;
-	u32 status;
-	int id;
+	u32 status, id;
 	u8 sid = (pmic_arb->apid_data[apid].ppid >> 8) & 0xF;
 	u8 per = pmic_arb->apid_data[apid].ppid & 0xFF;
 
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