[PATCH v3] i2c: tegra: Don't mark devices with pins as IRQ safe

[Mikko Perttunen]

I2C devices with associated pinctrl states (DPAUX I2C controllers)
will change pinctrl state during runtime PM. This requires taking
a mutex, so these devices cannot be marked as IRQ safe.

Add PINCTRL as dependency to avoid build errors.

Signed-off-by: Mikko Perttunen <mperttunen@xxxxxxxxxx>
---
Changes in v3:
- Moved PINCTRL dependency to its own line, and added clarifying
  comment.
- Link to v2: https://lore.kernel.org/r/20260217-i2c-dpaux-irqsafe-v2-1-635a4c43b1a7@xxxxxxxxxx

Changes in v2:
- Removed incorrect reference to lockdep in commit message.
- Added PINCTRL dependency when building for COMPILE_TEST.
  Tegra platforms already globally select PINCTRL, but COMPILE_TEST
  configurations may not.
- Link to v1: https://lore.kernel.org/r/20260202-i2c-dpaux-irqsafe-v1-1-5b1847e8bc97@xxxxxxxxxx
---
 drivers/i2c/busses/Kconfig     | 2 ++
 drivers/i2c/busses/i2c-tegra.c | 5 ++++-
 2 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
index e11d50750e63..7cb6b9b864a7 100644
--- a/drivers/i2c/busses/Kconfig
+++ b/drivers/i2c/busses/Kconfig
@@ -1213,6 +1213,8 @@ config I2C_TEGRA
 	tristate "NVIDIA Tegra internal I2C controller"
 	depends on ARCH_TEGRA || (COMPILE_TEST && (ARC || ARM || ARM64 || M68K || RISCV || SUPERH || SPARC))
 	# COMPILE_TEST needs architectures with readsX()/writesX() primitives
+	depends on PINCTRL
+	# ARCH_TEGRA implies PINCTRL, but the COMPILE_TEST side doesn't.
 	help
 	  If you say yes to this option, support will be included for the
 	  I2C controller embedded in NVIDIA Tegra SOCs
diff --git a/drivers/i2c/busses/i2c-tegra.c b/drivers/i2c/busses/i2c-tegra.c
index bec619b9af4e..4eaeb395d5db 100644
--- a/drivers/i2c/busses/i2c-tegra.c
+++ b/drivers/i2c/busses/i2c-tegra.c
@@ -2047,8 +2047,11 @@ static int tegra_i2c_probe(struct platform_device *pdev)
 	 *
 	 * VI I2C device shouldn't be marked as IRQ-safe because VI I2C won't
 	 * be used for atomic transfers. ACPI device is not IRQ safe also.
+	 *
+	 * Devices with pinctrl states cannot be marked IRQ-safe as the pinctrl
+	 * state transitions during runtime PM require mutexes.
 	 */
-	if (!IS_VI(i2c_dev) && !has_acpi_companion(i2c_dev->dev))
+	if (!IS_VI(i2c_dev) && !has_acpi_companion(i2c_dev->dev) && !i2c_dev->dev->pins)
 		pm_runtime_irq_safe(i2c_dev->dev);
 
 	pm_runtime_enable(i2c_dev->dev);

---
base-commit: 4f938c7d3b25d87b356af4106c2682caf8c835a2
change-id: 20260202-i2c-dpaux-irqsafe-edc04628b401