irqchip/renesas-rzv2h: Prevent TINT spurious interrupt during resume

irqchip/renesas-rzv2h: Prevent TINT spurious interrupt during resume

[ Upstream commit cd4a3ced4d1cdb14ffe905657b98a91e9d239dfb ]

A glitch in the edge detection circuit can cause a spurious interrupt. The
hardware manual recommends clearing the status flag after setting the
ICU_TSSRk register as a countermeasure.

Currently, a spurious interrupt is generated on the resume path of s2idle
for the PMIC RTC TINT interrupt due to a glitch related to unnecessary
enabling/disabling of the TINT enable bit.

Fix this issue by not setting TSSR(TINT Source) and TITSR(TINT Detection
Method Selection) registers if the values are the same as those set
in these registers.

Fixes: 0d7605e75ac2 ("irqchip: Add RZ/V2H(P) Interrupt Control Unit (ICU) driver")
Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com>
Signed-off-by: Thomas Gleixner <tglx@kernel.org>
Cc: stable@vger.kernel.org
Link: https://patch.msgid.link/20260113125315.359967-2-biju.das.jz@bp.renesas.com
[tm: Added field_get() to avoid build error]
Signed-off-by: Tommaso Merciai <tommaso.merciai.xr@bp.renesas.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>