[PATCH AUTOSEL 6.6 51/66] gpio: pxa: Make irq_chip immutable

[PATCH AUTOSEL 6.6 51/66] gpio: pxa: Make irq_chip immutable

[Sasha Levin]

From: Peng Fan <peng.fan@nxp.com>

[ Upstream commit 20117cf426b677e7aced4e7a1b2b37f6080a46dc ]

Kernel warns about mutable irq_chips:
"not an immutable chip, please consider fixing!"

Constify pxa_muxed_gpio_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-v1-9-639377c98288@nxp.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

**YES** This commit should be backported to stable kernel trees. Here's
my extensive analysis: ## Backport Analysis: gpio: pxa: Make irq_chip
immutable ### Code Changes Analysis The commit makes three key changes
to `drivers/gpio/gpio-pxa.c`: 1. **Makes irq_chip structure const**:
Changes `static struct irq_chip pxa_muxed_gpio_chip` to `static const
struct irq_chip pxa_muxed_gpio_chip` 2. **Adds IRQCHIP_IMMUTABLE flag**:
Includes `.flags = IRQCHIP_IMMUTABLE` in the irq_chip structure 3.
**Adds resource helper macros**: Includes
`GPIOCHIP_IRQ_RESOURCE_HELPERS` macro 4. **Updates mask/unmask
functions**: Adds proper `gpiochip_disable_irq()` and
`gpiochip_enable_irq()` calls in the mask and unmask functions
respectively ### Why This Should Be Backported **1. Follows Established
Pattern** This commit follows the exact same pattern as the reference
commits marked "YES" for backporting: - Similar to gpio-vf610 (commit
e6ef4f8ede09) which was backported - Identical to gpio-104-idio-16
(commit 410a5041aa60) which was backported - Same transformation pattern
as dozens of other GPIO drivers **2. Fixes Kernel Warning** The commit
explicitly addresses a kernel warning: "not an immutable chip, please
consider fixing!" This is the same warning addressed in all the
reference "YES" commits. **3. Small, Contained Changes** - Only modifies
one file (`drivers/gpio/gpio-pxa.c`) - Changes are minimal and
mechanical - No architectural changes or new features - Low risk of
introducing regressions **4. Important Bug Fix for Users** - Eliminates
annoying kernel warnings that users encounter - Brings driver in
compliance with modern kernel IRQ subsystem requirements - Improves
system reliability by preventing dynamic modification of irq_chip
callbacks **5. No Side Effects** - The changes are purely structural
improvements - Maintains identical functionality - Does not change the
driver's external behavior - Only makes the irq_chip structure immutable
for safety **6. Critical Subsystem Compliance** - GPIO subsystem
actively enforces immutable irq_chips - This is part of a kernel-wide
migration to improve memory safety - Prevents potential security issues
from dynamic irq_chip modification **7. Hardware Support Impact** The
PXA GPIO driver supports widely-used ARM processors: - Intel PXA25x,
PXA26x, PXA27x, PXA3xx series - Marvell PXA93x, MMP, MMP2, PXA1928
series - These are found in many embedded systems and IoT devices ###
Comparison with Current Tree The analysis shows that in the current
kernel tree (`/home/sasha/linux/`), the gpio-pxa.c driver still has the
old mutable irq_chip structure (line 523: `static struct irq_chip
pxa_muxed_gpio_chip`), while the target directory shows it has already
been converted. This confirms this is a legitimate conversion commit
that needs backporting. ### Risk Assessment **Very Low Risk:** -
Mechanical transformation following established pattern - No functional
changes to GPIO operations - Extensive precedent from similar successful
backports - Changes are compile-time enforced (const keyword) This
commit represents a straightforward compliance fix that eliminates user-
visible warnings while improving code safety, making it an ideal
candidate for stable tree backporting.

 drivers/gpio/gpio-pxa.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/gpio/gpio-pxa.c b/drivers/gpio/gpio-pxa.c
index cae9661862fe1..0e9f3baf1bd31 100644
--- a/drivers/gpio/gpio-pxa.c
+++ b/drivers/gpio/gpio-pxa.c
@@ -497,6 +497,8 @@ static void pxa_mask_muxed_gpio(struct irq_data *d)
 	gfer = readl_relaxed(base + GFER_OFFSET) & ~GPIO_bit(gpio);
 	writel_relaxed(grer, base + GRER_OFFSET);
 	writel_relaxed(gfer, base + GFER_OFFSET);
+
+	gpiochip_disable_irq(&pchip->chip, gpio);
 }
 
 static int pxa_gpio_set_wake(struct irq_data *d, unsigned int on)
@@ -516,17 +518,21 @@ static void pxa_unmask_muxed_gpio(struct irq_data *d)
 	unsigned int gpio = irqd_to_hwirq(d);
 	struct pxa_gpio_bank *c = gpio_to_pxabank(&pchip->chip, gpio);
 
+	gpiochip_enable_irq(&pchip->chip, gpio);
+
 	c->irq_mask |= GPIO_bit(gpio);
 	update_edge_detect(c);
 }
 
-static struct irq_chip pxa_muxed_gpio_chip = {
+static const struct irq_chip pxa_muxed_gpio_chip = {
 	.name		= "GPIO",
 	.irq_ack	= pxa_ack_muxed_gpio,
 	.irq_mask	= pxa_mask_muxed_gpio,
 	.irq_unmask	= pxa_unmask_muxed_gpio,
 	.irq_set_type	= pxa_gpio_irq_type,
 	.irq_set_wake	= pxa_gpio_set_wake,
+	.flags = IRQCHIP_IMMUTABLE,
+	GPIOCHIP_IRQ_RESOURCE_HELPERS,
 };
 
 static int pxa_gpio_nums(struct platform_device *pdev)
-- 
2.39.5

[PATCH AUTOSEL 6.6 52/66] gpio: grgpio: Make irq_chip immutable

[Sasha Levin]

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 637a4d45f8c77..243a28cfbd990 100644
--- a/drivers/gpio/gpio-grgpio.c
+++ b/drivers/gpio/gpio-grgpio.c
@@ -169,6 +169,8 @@ 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)
@@ -177,6 +179,7 @@ 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);
@@ -184,11 +187,13 @@ 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)
-- 
2.39.5

[PATCH AUTOSEL 6.6 53/66] gpio: xgene-sb: Make irq_chip immutable

[Sasha Levin]

From: Peng Fan <peng.fan@nxp.com>

[ Upstream commit 580b3264cb252cae00fa62d58443af09c25f7d61 ]

Kernel warns about mutable irq_chips:
"not an immutable chip, please consider fixing!"

Constify xgene_gpio_sb_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-v1-7-639377c98288@nxp.com
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

Based on my analysis of the commit and the kernel context, here is my
determination: **YES** This commit should be backported to stable kernel
trees. Here's my extensive analysis: ## Analysis of the Commit ### 1.
**Purpose and Nature of the Change** The commit addresses a kernel
warning about mutable irq_chips by converting the
`xgene_gpio_sb_irq_chip` to be immutable. This is a **bug fix** that
eliminates runtime warnings, not a new feature or architectural change.
### 2. **Code Changes Analysis** The changes are minimal and follow an
established pattern: **Key Changes:** - **Made struct const**: `static
struct irq_chip` → `static const struct irq_chip` - **Added
IRQCHIP_IMMUTABLE flag**: Prevents runtime modification of the irq_chip
- **Added resource helpers**: `GPIOCHIP_IRQ_RESOURCE_HELPERS` macro -
**Replaced direct parent calls with wrapper functions**: -
`irq_chip_mask_parent` → `xgene_gpio_sb_irq_mask` (which calls
`gpiochip_disable_irq` then `irq_chip_mask_parent`) -
`irq_chip_unmask_parent` → `xgene_gpio_sb_irq_unmask` (which calls
`gpiochip_enable_irq` then `irq_chip_unmask_parent`) ### 3. **Comparison
with Similar Commits** This commit follows **exactly the same pattern**
as the similar commits marked "YES" for backporting: - **gpio: vf610:
make irq_chip immutable** (Status: YES) - **gpio: 104-idio-16: Make
irq_chip immutable** (Status: YES) The changes are nearly identical in
structure and purpose to these approved backports. ### 4. **Risk
Assessment** **Very Low Risk:** - **Contained change**: Only affects the
xgene-sb GPIO driver - **Follows established pattern**: The
IRQCHIP_IMMUTABLE pattern has been widely adopted across GPIO drivers
since kernel v5.19 - **No functional behavior change**: The GPIO
operations work exactly the same way - **Well-tested pattern**: Multiple
GPIO drivers have successfully adopted this pattern ### 5. **Backport
Criteria Evaluation** ✅ **Fixes a bug**: Eliminates kernel warning about
mutable irq_chips ✅ **Small and contained**: Only 20 lines changed in a
single driver ✅ **No side effects**: Change is purely about chip
mutability, not functionality ✅ **No architectural changes**: Uses
existing infrastructure introduced in v5.19 ✅ **Follows stable rules**:
Important bugfix with minimal regression risk ✅ **Critical subsystem
consideration**: GPIO is used widely, but change is driver-specific ###
6. **Historical Context** The IRQCHIP_IMMUTABLE pattern and supporting
infrastructure were introduced in linux-kernel v5.19** (commit
36b78aae4bfe). This commit uses the same established APIs
(`gpiochip_enable_irq`, `gpiochip_disable_irq`,
`GPIOCHIP_IRQ_RESOURCE_HELPERS`) that have been stable since then. ###
7. **Warning Elimination** The commit specifically addresses the kernel
warning "not an immutable chip, please consider fixing!" which can be
disruptive in production environments. Eliminating such warnings
improves system stability and reduces noise in kernel logs. ###
Conclusion This is a straightforward bugfix that follows a well-
established, low-risk pattern adopted by numerous GPIO drivers. It
eliminates kernel warnings without changing functional behavior, making
it an ideal candidate for stable tree backporting.

 drivers/gpio/gpio-xgene-sb.c | 26 +++++++++++++++++++++++---
 1 file changed, 23 insertions(+), 3 deletions(-)

diff --git a/drivers/gpio/gpio-xgene-sb.c b/drivers/gpio/gpio-xgene-sb.c
index a809609ee9570..6b799c17902c9 100644
--- a/drivers/gpio/gpio-xgene-sb.c
+++ b/drivers/gpio/gpio-xgene-sb.c
@@ -102,12 +102,32 @@ static int xgene_gpio_sb_irq_set_type(struct irq_data *d, unsigned int type)
 		return irq_chip_set_type_parent(d, IRQ_TYPE_LEVEL_HIGH);
 }
 
-static struct irq_chip xgene_gpio_sb_irq_chip = {
+static void xgene_gpio_sb_irq_mask(struct irq_data *d)
+{
+	struct xgene_gpio_sb *priv = irq_data_get_irq_chip_data(d);
+
+	irq_chip_mask_parent(d);
+
+	gpiochip_disable_irq(&priv->gc, d->hwirq);
+}
+
+static void xgene_gpio_sb_irq_unmask(struct irq_data *d)
+{
+	struct xgene_gpio_sb *priv = irq_data_get_irq_chip_data(d);
+
+	gpiochip_enable_irq(&priv->gc, d->hwirq);
+
+	irq_chip_unmask_parent(d);
+}
+
+static const struct irq_chip xgene_gpio_sb_irq_chip = {
 	.name           = "sbgpio",
 	.irq_eoi	= irq_chip_eoi_parent,
-	.irq_mask       = irq_chip_mask_parent,
-	.irq_unmask     = irq_chip_unmask_parent,
+	.irq_mask       = xgene_gpio_sb_irq_mask,
+	.irq_unmask     = xgene_gpio_sb_irq_unmask,
 	.irq_set_type   = xgene_gpio_sb_irq_set_type,
+	.flags = IRQCHIP_IMMUTABLE,
+	GPIOCHIP_IRQ_RESOURCE_HELPERS,
 };
 
 static int xgene_gpio_sb_to_irq(struct gpio_chip *gc, u32 gpio)
-- 
2.39.5

[PATCH AUTOSEL 6.6 65/66] gpio: ds4520: don't check the 'ngpios' property in the driver

[Sasha Levin]

From: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>

[ Upstream commit df1540f8f311a8b2ef0e450e7e40710784acc8c7 ]

This is already done by the gpio-regmap abstraction by calling
gpiochip_get_ngpios(). We don't need to do this at the driver level.

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Link: https://lore.kernel.org/r/20250408-gpio-regmap-ngpios-v2-1-26f254014f57@linaro.org
Signed-off-by: Bartosz Golaszewski <brgl@bgdev.pl>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---

NO This commit should NOT be backported to stable kernel trees.
**Analysis:** This commit removes driver-level handling of the 'ngpios'
property in the ds4520 GPIO driver, relying instead on the gpio-regmap
abstraction layer to handle this automatically via
`gpiochip_get_ngpios()`. **Reasons this should NOT be backported:** 1.
**Code cleanup, not a bugfix**: The commit message explicitly states
"This is already done by the gpio-regmap abstraction by calling
gpiochip_get_ngpios(). We don't need to do this at the driver level."
This indicates the change removes redundant code rather than fixing a
functional issue. 2. **No user-visible impact**: Both the before and
after code achieve the same functionality - reading the 'ngpios'
property and configuring the GPIO count. The driver worked correctly
before this change. 3. **Architectural cleanup**: The change moves
responsibility from the driver level to the abstraction layer, which is
a code organization improvement rather than a critical fix. 4. **Missing
infrastructure dependencies**: Looking at the code in
`/home/sasha/linux/drivers/gpio/gpio-regmap.c:274-278`, the automatic
ngpios handling was added in commit db305161880a "gpio: regmap: Allow
ngpio to be read from the property". Without this infrastructure change
being backported first, this commit would break the ds4520 driver in
stable trees. 5. **Similar commits marked NO**: The reference commits
show that code organization changes (#1, #4, #5) are marked as NO for
backporting, while actual bugfixes (#2, #3) are marked as YES. 6. **No
stable tree indicators**: The commit message contains no "Fixes:" tag,
"Cc: stable" notation, or indication that this addresses a user-
impacting issue. 7. **Risk vs benefit**: The change removes 6 lines of
working code (lines 28, 36-38, 47 in the original) without fixing any
reported issues. The risk of regression outweighs any benefit for stable
trees. The ds4520 driver was relatively new (first commit 659ad5f7efec)
and this cleanup came shortly after, making it an optimization rather
than a critical fix requiring backport.

 drivers/gpio/gpio-ds4520.c | 6 ------
 1 file changed, 6 deletions(-)

diff --git a/drivers/gpio/gpio-ds4520.c b/drivers/gpio/gpio-ds4520.c
index 1903deaef3e9b..f52ecae382a45 100644
--- a/drivers/gpio/gpio-ds4520.c
+++ b/drivers/gpio/gpio-ds4520.c
@@ -25,7 +25,6 @@ static int ds4520_gpio_probe(struct i2c_client *client)
 	struct gpio_regmap_config config = { };
 	struct device *dev = &client->dev;
 	struct regmap *regmap;
-	u32 ngpio;
 	u32 base;
 	int ret;
 
@@ -33,10 +32,6 @@ static int ds4520_gpio_probe(struct i2c_client *client)
 	if (ret)
 		return dev_err_probe(dev, ret, "Missing 'reg' property.\n");
 
-	ret = device_property_read_u32(dev, "ngpios", &ngpio);
-	if (ret)
-		return dev_err_probe(dev, ret, "Missing 'ngpios' property.\n");
-
 	regmap = devm_regmap_init_i2c(client, &ds4520_regmap_config);
 	if (IS_ERR(regmap))
 		return dev_err_probe(dev, PTR_ERR(regmap),
@@ -44,7 +39,6 @@ static int ds4520_gpio_probe(struct i2c_client *client)
 
 	config.regmap = regmap;
 	config.parent = dev;
-	config.ngpio = ngpio;
 
 	config.reg_dat_base = base + DS4520_IO_STATUS0;
 	config.reg_set_base = base + DS4520_PULLUP0;
-- 
2.39.5