On the Axiado AX3000 platform, pinmux and pin configuration (such as
direction and output enable) are configured by the hardware/firmware
at boot time before Linux boots.
To prevent conflicts, introduce a platform-specific quirk triggered by
the "axiado,ax3000-gpio" compatible string.
When this quirk is active, the driver will skip its default
initialization of pinmux configuration and direction settings during
probe.
Co-developed-by: Tzu-Hao Wei <twei@axiado.com>
Signed-off-by: Tzu-Hao Wei <twei@axiado.com>
Signed-off-by: Swark Yang <syang@axiado.com>
Signed-off-by: Prasad Bolisetty <pbolisetty@axiado.com>
---
drivers/gpio/gpio-cadence.c | 53 +++++++++++++++++++++++++++++++++++----------
1 file changed, 42 insertions(+), 11 deletions(-)
diff --git a/drivers/gpio/gpio-cadence.c b/drivers/gpio/gpio-cadence.c
index b75734ca22dd..b9f39566b0f9 100644
--- a/drivers/gpio/gpio-cadence.c
+++ b/drivers/gpio/gpio-cadence.c
@@ -6,6 +6,9 @@
* Authors:
* Jan Kotas <jank@cadence.com>
* Boris Brezillon <boris.brezillon@free-electrons.com>
+ *
+ * Copyright (C) 2025 Axiado Corporation.
+ *
*/
#include <linux/cleanup.h>
@@ -31,12 +34,18 @@
#define CDNS_GPIO_IRQ_VALUE 0x28
#define CDNS_GPIO_IRQ_ANY_EDGE 0x2c
+#define CDNS_GPIO_QUIRKS_SKIP_PINMUX_CFG BIT(1)
+
struct cdns_gpio_chip {
struct gpio_generic_chip gen_gc;
void __iomem *regs;
u32 bypass_orig;
};
+struct cdns_platform_data {
+ u32 quirks;
+};
+
static int cdns_gpio_request(struct gpio_chip *chip, unsigned int offset)
{
struct cdns_gpio_chip *cgpio = gpiochip_get_data(chip);
@@ -141,6 +150,16 @@ static const struct irq_chip cdns_gpio_irqchip = {
GPIOCHIP_IRQ_RESOURCE_HELPERS,
};
+static const struct cdns_platform_data ax3000_gpio_def = {
+ .quirks = CDNS_GPIO_QUIRKS_SKIP_PINMUX_CFG, };
+
+static const struct of_device_id cdns_of_ids[] = {
+ { .compatible = "axiado,ax3000-gpio", .data = &ax3000_gpio_def },
+ { .compatible = "cdns,gpio-r1p02" },
+ { /* sentinel */ },
+};
+MODULE_DEVICE_TABLE(of, cdns_of_ids);
+
static int cdns_gpio_probe(struct platform_device *pdev)
{
struct gpio_generic_chip_config config = { };
@@ -148,6 +167,8 @@ static int cdns_gpio_probe(struct platform_device *pdev)
int ret, irq;
u32 dir_prev;
u32 num_gpios = 32;
+ bool skip_pinmux_cfg = false;
+ const struct of_device_id *match;
struct clk *clk;
cgpio = devm_kzalloc(&pdev->dev, sizeof(*cgpio), GFP_KERNEL);
@@ -165,6 +186,13 @@ static int cdns_gpio_probe(struct platform_device *pdev)
return -EINVAL;
}
+ match = of_match_node(cdns_of_ids, pdev->dev.of_node);
+ if (match && match->data) {
+ const struct cdns_platform_data *data = match->data;
+
+ skip_pinmux_cfg = data->quirks & CDNS_GPIO_QUIRKS_SKIP_PINMUX_CFG;
+ }
+
/*
* Set all pins as inputs by default, otherwise:
* gpiochip_lock_as_irq:
@@ -173,8 +201,15 @@ static int cdns_gpio_probe(struct platform_device *pdev)
* so it needs to be changed before gpio_generic_chip_init() is called.
*/
dir_prev = ioread32(cgpio->regs + CDNS_GPIO_DIRECTION_MODE);
- iowrite32(GENMASK(num_gpios - 1, 0),
- cgpio->regs + CDNS_GPIO_DIRECTION_MODE);
+
+ /*
+ * The AX3000 platform performs the required configuration at boot time
+ * before Linux boots, so this quirk disables pinmux initialization.
+ */
+ if (!skip_pinmux_cfg) {
+ iowrite32(GENMASK(num_gpios - 1, 0),
+ cgpio->regs + CDNS_GPIO_DIRECTION_MODE);
+ }
config.dev = &pdev->dev;
config.sz = 4;
@@ -240,9 +275,11 @@ static int cdns_gpio_probe(struct platform_device *pdev)
/*
* Enable gpio outputs, ignored for input direction
*/
- iowrite32(GENMASK(num_gpios - 1, 0),
- cgpio->regs + CDNS_GPIO_OUTPUT_EN);
- iowrite32(0, cgpio->regs + CDNS_GPIO_BYPASS_MODE);
+ if (!skip_pinmux_cfg) {
+ iowrite32(GENMASK(num_gpios - 1, 0),
+ cgpio->regs + CDNS_GPIO_OUTPUT_EN);
+ iowrite32(0, cgpio->regs + CDNS_GPIO_BYPASS_MODE);
+ }
platform_set_drvdata(pdev, cgpio);
return 0;
@@ -260,12 +297,6 @@ static void cdns_gpio_remove(struct platform_device *pdev)
iowrite32(cgpio->bypass_orig, cgpio->regs + CDNS_GPIO_BYPASS_MODE);
}
-static const struct of_device_id cdns_of_ids[] = {
- { .compatible = "cdns,gpio-r1p02" },
- { /* sentinel */ },
-};
-MODULE_DEVICE_TABLE(of, cdns_of_ids);
-
static struct platform_driver cdns_gpio_driver = {
.driver = {
.name = "cdns-gpio",
--
2.25.1Hi Swark,
thanks for your patch!
On Tue, Dec 23, 2025 at 8:30 AM Swark Yang <syang@axiado.com> wrote:
> On the Axiado AX3000 platform, pinmux and pin configuration (such as
> direction and output enable) are configured by the hardware/firmware
> at boot time before Linux boots.
>
> To prevent conflicts, introduce a platform-specific quirk triggered by
> the "axiado,ax3000-gpio" compatible string.
>
> When this quirk is active, the driver will skip its default
> initialization of pinmux configuration and direction settings during
> probe.
>
> Co-developed-by: Tzu-Hao Wei <twei@axiado.com>
> Signed-off-by: Tzu-Hao Wei <twei@axiado.com>
> Signed-off-by: Swark Yang <syang@axiado.com>
> Signed-off-by: Prasad Bolisetty <pbolisetty@axiado.com>
> +#define CDNS_GPIO_QUIRKS_SKIP_PINMUX_CFG BIT(1)
This is just using bits and copying stuff unnecessarily.
Do this:
struct cdns_gpio_quirks {
bool skip_init;
};
> struct cdns_gpio_chip {
> struct gpio_generic_chip gen_gc;
> void __iomem *regs;
> u32 bypass_orig;
In this struct add:
struct cdns_gpio_quirks *quirks;
And assign it in probe.
> +struct cdns_platform_data {
> + u32 quirks;
> +};
Skip this double-translated thing.
> static int cdns_gpio_request(struct gpio_chip *chip, unsigned int offset)
> {
> struct cdns_gpio_chip *cgpio = gpiochip_get_data(chip);
> @@ -141,6 +150,16 @@ static const struct irq_chip cdns_gpio_irqchip = {
> GPIOCHIP_IRQ_RESOURCE_HELPERS,
> };
>
> +static const struct cdns_platform_data ax3000_gpio_def = {
> + .quirks = CDNS_GPIO_QUIRKS_SKIP_PINMUX_CFG, };
static const struct cdns_gpio_quirks cdns_default_quirks = {
.skip_init = true,
};
static const struct cdns_gpio_quirks ax300_gpio_quirks = {
.skip_init = true,
};
> +static const struct of_device_id cdns_of_ids[] = {
> + { .compatible = "axiado,ax3000-gpio", .data = &ax3000_gpio_def },
.data = &ax3000_gpio_quirks,
> + { .compatible = "cdns,gpio-r1p02" },
.data = &cdns_default_quirks,
This becomes more manageable, as I know there is *at least* one
more variant arriving, which is for CIX semiconductors and who knows
how many quirks we will have to carry in the future.
> static int cdns_gpio_probe(struct platform_device *pdev)
> {
> struct gpio_generic_chip_config config = { };
> @@ -148,6 +167,8 @@ static int cdns_gpio_probe(struct platform_device *pdev)
> int ret, irq;
> u32 dir_prev;
> u32 num_gpios = 32;
> + bool skip_pinmux_cfg = false;
Nah, just reference the quirk.
> + const struct of_device_id *match;
> struct clk *clk;
>
> cgpio = devm_kzalloc(&pdev->dev, sizeof(*cgpio), GFP_KERNEL);
> @@ -165,6 +186,13 @@ static int cdns_gpio_probe(struct platform_device *pdev)
> return -EINVAL;
> }
>
> + match = of_match_node(cdns_of_ids, pdev->dev.of_node);
> + if (match && match->data) {
> + const struct cdns_platform_data *data = match->data;
> +
> + skip_pinmux_cfg = data->quirks & CDNS_GPIO_QUIRKS_SKIP_PINMUX_CFG;
> + }
Instead do:
cgpio->quirks = device_get_match_data() like Bartosz suggests.
> dir_prev = ioread32(cgpio->regs + CDNS_GPIO_DIRECTION_MODE);
> - iowrite32(GENMASK(num_gpios - 1, 0),
> - cgpio->regs + CDNS_GPIO_DIRECTION_MODE);
> +
> + /*
> + * The AX3000 platform performs the required configuration at boot time
> + * before Linux boots, so this quirk disables pinmux initialization.
> + */
> + if (!skip_pinmux_cfg) {
Here:
if (cgpio->quirks->skip_init) {
> + iowrite32(GENMASK(num_gpios - 1, 0),
> + cgpio->regs + CDNS_GPIO_DIRECTION_MODE);
> + }
>
> config.dev = &pdev->dev;
> config.sz = 4;
> @@ -240,9 +275,11 @@ static int cdns_gpio_probe(struct platform_device *pdev)
> /*
> * Enable gpio outputs, ignored for input direction
> */
> - iowrite32(GENMASK(num_gpios - 1, 0),
> - cgpio->regs + CDNS_GPIO_OUTPUT_EN);
> - iowrite32(0, cgpio->regs + CDNS_GPIO_BYPASS_MODE);
> + if (!skip_pinmux_cfg) {
if (cgpio->quirks->skip_init) {
> + iowrite32(GENMASK(num_gpios - 1, 0),
> + cgpio->regs + CDNS_GPIO_OUTPUT_EN);
This has nothing to do with pinmux whatsoever so it is better to call
this quirk "skip_init"
> + iowrite32(0, cgpio->regs + CDNS_GPIO_BYPASS_MODE);
This affects the pinmuxing though. But the muxing happens outside
of the GPIO block itself.
Yours,
Linus Walleij
On Tue, Dec 23, 2025 at 8:30 AM Swark Yang <syang@axiado.com> wrote:
>
> On the Axiado AX3000 platform, pinmux and pin configuration (such as
> direction and output enable) are configured by the hardware/firmware
> at boot time before Linux boots.
>
> To prevent conflicts, introduce a platform-specific quirk triggered by
> the "axiado,ax3000-gpio" compatible string.
>
> When this quirk is active, the driver will skip its default
> initialization of pinmux configuration and direction settings during
> probe.
>
> Co-developed-by: Tzu-Hao Wei <twei@axiado.com>
> Signed-off-by: Tzu-Hao Wei <twei@axiado.com>
> Signed-off-by: Swark Yang <syang@axiado.com>
> Signed-off-by: Prasad Bolisetty <pbolisetty@axiado.com>
> ---
> drivers/gpio/gpio-cadence.c | 53 +++++++++++++++++++++++++++++++++++----------
> 1 file changed, 42 insertions(+), 11 deletions(-)
>
> diff --git a/drivers/gpio/gpio-cadence.c b/drivers/gpio/gpio-cadence.c
> index b75734ca22dd..b9f39566b0f9 100644
> --- a/drivers/gpio/gpio-cadence.c
> +++ b/drivers/gpio/gpio-cadence.c
> @@ -6,6 +6,9 @@
> * Authors:
> * Jan Kotas <jank@cadence.com>
> * Boris Brezillon <boris.brezillon@free-electrons.com>
> + *
> + * Copyright (C) 2025 Axiado Corporation.
Move this to where the original copyright is.
> + *
> */
>
> #include <linux/cleanup.h>
> @@ -31,12 +34,18 @@
> #define CDNS_GPIO_IRQ_VALUE 0x28
> #define CDNS_GPIO_IRQ_ANY_EDGE 0x2c
>
> +#define CDNS_GPIO_QUIRKS_SKIP_PINMUX_CFG BIT(1)
> +
> struct cdns_gpio_chip {
> struct gpio_generic_chip gen_gc;
> void __iomem *regs;
> u32 bypass_orig;
> };
>
> +struct cdns_platform_data {
> + u32 quirks;
> +};
> +
> static int cdns_gpio_request(struct gpio_chip *chip, unsigned int offset)
> {
> struct cdns_gpio_chip *cgpio = gpiochip_get_data(chip);
> @@ -141,6 +150,16 @@ static const struct irq_chip cdns_gpio_irqchip = {
> GPIOCHIP_IRQ_RESOURCE_HELPERS,
> };
>
> +static const struct cdns_platform_data ax3000_gpio_def = {
> + .quirks = CDNS_GPIO_QUIRKS_SKIP_PINMUX_CFG, };
Didn't checkpatch complain about the trailing bracket? Please move it
to the next line.
> +
> +static const struct of_device_id cdns_of_ids[] = {
> + { .compatible = "axiado,ax3000-gpio", .data = &ax3000_gpio_def },
> + { .compatible = "cdns,gpio-r1p02" },
> + { /* sentinel */ },
> +};
> +MODULE_DEVICE_TABLE(of, cdns_of_ids);
> +
> static int cdns_gpio_probe(struct platform_device *pdev)
> {
> struct gpio_generic_chip_config config = { };
> @@ -148,6 +167,8 @@ static int cdns_gpio_probe(struct platform_device *pdev)
> int ret, irq;
> u32 dir_prev;
> u32 num_gpios = 32;
> + bool skip_pinmux_cfg = false;
> + const struct of_device_id *match;
> struct clk *clk;
>
> cgpio = devm_kzalloc(&pdev->dev, sizeof(*cgpio), GFP_KERNEL);
> @@ -165,6 +186,13 @@ static int cdns_gpio_probe(struct platform_device *pdev)
> return -EINVAL;
> }
>
> + match = of_match_node(cdns_of_ids, pdev->dev.of_node);
Just use device_get_match_data().
> + if (match && match->data) {
> + const struct cdns_platform_data *data = match->data;
> +
> + skip_pinmux_cfg = data->quirks & CDNS_GPIO_QUIRKS_SKIP_PINMUX_CFG;
> + }
> +
> /*
> * Set all pins as inputs by default, otherwise:
> * gpiochip_lock_as_irq:
> @@ -173,8 +201,15 @@ static int cdns_gpio_probe(struct platform_device *pdev)
> * so it needs to be changed before gpio_generic_chip_init() is called.
> */
> dir_prev = ioread32(cgpio->regs + CDNS_GPIO_DIRECTION_MODE);
> - iowrite32(GENMASK(num_gpios - 1, 0),
> - cgpio->regs + CDNS_GPIO_DIRECTION_MODE);
> +
> + /*
> + * The AX3000 platform performs the required configuration at boot time
> + * before Linux boots, so this quirk disables pinmux initialization.
> + */
> + if (!skip_pinmux_cfg) {
> + iowrite32(GENMASK(num_gpios - 1, 0),
> + cgpio->regs + CDNS_GPIO_DIRECTION_MODE);
> + }
>
> config.dev = &pdev->dev;
> config.sz = 4;
> @@ -240,9 +275,11 @@ static int cdns_gpio_probe(struct platform_device *pdev)
> /*
> * Enable gpio outputs, ignored for input direction
> */
> - iowrite32(GENMASK(num_gpios - 1, 0),
> - cgpio->regs + CDNS_GPIO_OUTPUT_EN);
> - iowrite32(0, cgpio->regs + CDNS_GPIO_BYPASS_MODE);
> + if (!skip_pinmux_cfg) {
> + iowrite32(GENMASK(num_gpios - 1, 0),
> + cgpio->regs + CDNS_GPIO_OUTPUT_EN);
> + iowrite32(0, cgpio->regs + CDNS_GPIO_BYPASS_MODE);
> + }
>
> platform_set_drvdata(pdev, cgpio);
> return 0;
> @@ -260,12 +297,6 @@ static void cdns_gpio_remove(struct platform_device *pdev)
> iowrite32(cgpio->bypass_orig, cgpio->regs + CDNS_GPIO_BYPASS_MODE);
> }
>
> -static const struct of_device_id cdns_of_ids[] = {
> - { .compatible = "cdns,gpio-r1p02" },
> - { /* sentinel */ },
> -};
> -MODULE_DEVICE_TABLE(of, cdns_of_ids);
> -
> static struct platform_driver cdns_gpio_driver = {
> .driver = {
> .name = "cdns-gpio",
>
> --
> 2.25.1
>
Bart
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