spmi: spmi-pmic-arb: Fix hw_irq overflow

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.

---
 drivers/spmi/spmi-pmic-arb.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

index de844b4..bbbd311 100644
@@ -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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Quoting Subbaraman Narayanamurthy (2021-02-08 11:33:04)

Applied to spmi-next