From: Peng Fan peng.fan@nxp.com
[ Upstream commit a30be40bf1d4437646b6885e7e4e71530e6f82c1 ]
Kernel warns about mutable irq_chips: "not an immutable chip, please consider fixing!"
Constify grgpio_irq_chip, flag the irq_chip as IRQCHIP_IMMUTABLE, add the new helper functions, and call the appropriate gpiolib functions.
Signed-off-by: Peng Fan peng.fan@nxp.com Reviewed-by: Linus Walleij linus.walleij@linaro.org Link: https://lore.kernel.org/r/20250509-gpio-v1-2-639377c98288@nxp.com Signed-off-by: Bartosz Golaszewski bartosz.golaszewski@linaro.org Signed-off-by: Sasha Levin sashal@kernel.org ---
Now let me analyze this commit against stable backporting criteria: **YES** ## Analysis: ### 1. Bug Fix Nature This commit fixes a kernel warning about mutable irq_chips with the message "not an immutable chip, please consider fixing!" This is clearly a bug fix that addresses a runtime warning that affects users. ### 2. Code Changes Analysis The changes are minimal and well-contained within the grgpio driver: - **Line 173**: Added `gpiochip_disable_irq(&priv->gc, d->hwirq);` call in `grgpio_irq_mask()` function - **Line 183**: Added `gpiochip_enable_irq(&priv->gc, d->hwirq);` call in `grgpio_irq_unmask()` function - **Line 191**: Made `grgpio_irq_chip` struct `const` (immutable) - **Lines 196-197**: Added `IRQCHIP_IMMUTABLE` flag and `GPIOCHIP_IRQ_RESOURCE_HELPERS` macro ### 3. Pattern Consistency with Similar Commits This commit follows the exact same pattern as the approved backport commits in the reference examples: - **Similar to gpio-104-idio-16** (Status: YES): Same pattern of making irq_chip const, adding IRQCHIP_IMMUTABLE flag, and adding gpiochip_enable/disable_irq calls - **Similar to gpio-vf610** (Status: YES): Identical changes - const irq_chip, IRQCHIP_IMMUTABLE, and proper helper function calls - **Similar to gpio-104-dio-48e** (Status: YES): Same transformation pattern ### 4. Risk Assessment - **Low Risk**: Changes are mechanical transformations following established GPIO subsystem patterns - **No Architectural Changes**: The commit doesn't modify core logic, just adapts to new GPIO framework requirements - **Well-Tested Pattern**: This exact change pattern has been applied across multiple GPIO drivers successfully ### 5. Stable Tree Compliance - **Important Bug Fix**: Eliminates kernel warnings that users encounter - **Minimal Risk**: The changes follow well-established patterns already proven in other GPIO drivers - **Contained Changes**: All modifications are within a single driver file with no cross-subsystem impact - **No New Features**: This is purely a compliance fix for the GPIO framework requirements ### 6. Framework Compliance The commit brings the grgpio driver into compliance with the modern GPIO framework's requirements for immutable irq_chips, which is a necessary change to prevent kernel warnings and ensure proper resource management. The changes are essential for maintaining driver functionality in current kernels and preventing user-visible warnings, making this an ideal candidate for stable tree backporting.
drivers/gpio/gpio-grgpio.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-)
diff --git a/drivers/gpio/gpio-grgpio.c b/drivers/gpio/gpio-grgpio.c index 30a0522ae735f..68cca7751c0e5 100644 --- a/drivers/gpio/gpio-grgpio.c +++ b/drivers/gpio/gpio-grgpio.c @@ -170,6 +170,8 @@ static void grgpio_irq_mask(struct irq_data *d) grgpio_set_imask(priv, offset, 0);
raw_spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags); + + gpiochip_disable_irq(&priv->gc, d->hwirq); }
static void grgpio_irq_unmask(struct irq_data *d) @@ -178,6 +180,7 @@ static void grgpio_irq_unmask(struct irq_data *d) int offset = d->hwirq; unsigned long flags;
+ gpiochip_enable_irq(&priv->gc, d->hwirq); raw_spin_lock_irqsave(&priv->gc.bgpio_lock, flags);
grgpio_set_imask(priv, offset, 1); @@ -185,11 +188,13 @@ static void grgpio_irq_unmask(struct irq_data *d) raw_spin_unlock_irqrestore(&priv->gc.bgpio_lock, flags); }
-static struct irq_chip grgpio_irq_chip = { +static const struct irq_chip grgpio_irq_chip = { .name = "grgpio", .irq_mask = grgpio_irq_mask, .irq_unmask = grgpio_irq_unmask, .irq_set_type = grgpio_irq_set_type, + .flags = IRQCHIP_IMMUTABLE, + GPIOCHIP_IRQ_RESOURCE_HELPERS, };
static irqreturn_t grgpio_irq_handler(int irq, void *dev)