[PATCH 2/9] gpio: siox: Convert to immutable irq_chip

From: Linus Walleij
Date: Mon Mar 20 2023 - 05:55:43 EST


Convert the driver to immutable irq-chip with a bit of
intuition.

In this case I had to figure out a way to get to the
struct gpio_chip that would work even when the irq_chip
is not part of the driver state container. I did this by
just doing what most other GPIO drivers do and pass
the state struct as data to devm_gpiochip_add_data()
and rewrite accordingly.

Cc: Marc Zyngier <maz@xxxxxxxxxx>
Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx>
---
drivers/gpio/gpio-siox.c | 75 ++++++++++++++++++++++++------------------------
1 file changed, 38 insertions(+), 37 deletions(-)

diff --git a/drivers/gpio/gpio-siox.c b/drivers/gpio/gpio-siox.c
index f8c5e9fc4bac..051bc99bdfb2 100644
--- a/drivers/gpio/gpio-siox.c
+++ b/drivers/gpio/gpio-siox.c
@@ -10,7 +10,6 @@

struct gpio_siox_ddata {
struct gpio_chip gchip;
- struct irq_chip ichip;
struct mutex lock;
u8 setdata[1];
u8 getdata[3];
@@ -97,9 +96,8 @@ static int gpio_siox_get_data(struct siox_device *sdevice, const u8 buf[])

static void gpio_siox_irq_ack(struct irq_data *d)
{
- struct irq_chip *ic = irq_data_get_irq_chip(d);
- struct gpio_siox_ddata *ddata =
- container_of(ic, struct gpio_siox_ddata, ichip);
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct gpio_siox_ddata *ddata = gpiochip_get_data(gc);

raw_spin_lock(&ddata->irqlock);
ddata->irq_status &= ~(1 << d->hwirq);
@@ -108,21 +106,21 @@ static void gpio_siox_irq_ack(struct irq_data *d)

static void gpio_siox_irq_mask(struct irq_data *d)
{
- struct irq_chip *ic = irq_data_get_irq_chip(d);
- struct gpio_siox_ddata *ddata =
- container_of(ic, struct gpio_siox_ddata, ichip);
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct gpio_siox_ddata *ddata = gpiochip_get_data(gc);

raw_spin_lock(&ddata->irqlock);
ddata->irq_enable &= ~(1 << d->hwirq);
raw_spin_unlock(&ddata->irqlock);
+ gpiochip_disable_irq(gc, irqd_to_hwirq(d));
}

static void gpio_siox_irq_unmask(struct irq_data *d)
{
- struct irq_chip *ic = irq_data_get_irq_chip(d);
- struct gpio_siox_ddata *ddata =
- container_of(ic, struct gpio_siox_ddata, ichip);
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct gpio_siox_ddata *ddata = gpiochip_get_data(gc);

+ gpiochip_enable_irq(gc, irqd_to_hwirq(d));
raw_spin_lock(&ddata->irqlock);
ddata->irq_enable |= 1 << d->hwirq;
raw_spin_unlock(&ddata->irqlock);
@@ -130,9 +128,8 @@ static void gpio_siox_irq_unmask(struct irq_data *d)

static int gpio_siox_irq_set_type(struct irq_data *d, u32 type)
{
- struct irq_chip *ic = irq_data_get_irq_chip(d);
- struct gpio_siox_ddata *ddata =
- container_of(ic, struct gpio_siox_ddata, ichip);
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct gpio_siox_ddata *ddata = gpiochip_get_data(gc);

raw_spin_lock(&ddata->irqlock);
ddata->irq_type[d->hwirq] = type;
@@ -143,8 +140,7 @@ static int gpio_siox_irq_set_type(struct irq_data *d, u32 type)

static int gpio_siox_get(struct gpio_chip *chip, unsigned int offset)
{
- struct gpio_siox_ddata *ddata =
- container_of(chip, struct gpio_siox_ddata, gchip);
+ struct gpio_siox_ddata *ddata = gpiochip_get_data(chip);
int ret;

mutex_lock(&ddata->lock);
@@ -167,8 +163,7 @@ static int gpio_siox_get(struct gpio_chip *chip, unsigned int offset)
static void gpio_siox_set(struct gpio_chip *chip,
unsigned int offset, int value)
{
- struct gpio_siox_ddata *ddata =
- container_of(chip, struct gpio_siox_ddata, gchip);
+ struct gpio_siox_ddata *ddata = gpiochip_get_data(chip);
u8 mask = 1 << (19 - offset);

mutex_lock(&ddata->lock);
@@ -208,11 +203,22 @@ static int gpio_siox_get_direction(struct gpio_chip *chip, unsigned int offset)
return GPIO_LINE_DIRECTION_OUT;
}

+static const struct irq_chip gpio_siox_irq_chip = {
+ .name = "siox-gpio",
+ .irq_ack = gpio_siox_irq_ack,
+ .irq_mask = gpio_siox_irq_mask,
+ .irq_unmask = gpio_siox_irq_unmask,
+ .irq_set_type = gpio_siox_irq_set_type,
+ .flags = IRQCHIP_IMMUTABLE,
+ GPIOCHIP_IRQ_RESOURCE_HELPERS,
+};
+
static int gpio_siox_probe(struct siox_device *sdevice)
{
struct gpio_siox_ddata *ddata;
struct gpio_irq_chip *girq;
struct device *dev = &sdevice->dev;
+ struct gpio_chip *gc;
int ret;

ddata = devm_kzalloc(dev, sizeof(*ddata), GFP_KERNEL);
@@ -224,30 +230,25 @@ static int gpio_siox_probe(struct siox_device *sdevice)
mutex_init(&ddata->lock);
raw_spin_lock_init(&ddata->irqlock);

- ddata->gchip.base = -1;
- ddata->gchip.can_sleep = 1;
- ddata->gchip.parent = dev;
- ddata->gchip.owner = THIS_MODULE;
- ddata->gchip.get = gpio_siox_get;
- ddata->gchip.set = gpio_siox_set;
- ddata->gchip.direction_input = gpio_siox_direction_input;
- ddata->gchip.direction_output = gpio_siox_direction_output;
- ddata->gchip.get_direction = gpio_siox_get_direction;
- ddata->gchip.ngpio = 20;
-
- ddata->ichip.name = "siox-gpio";
- ddata->ichip.irq_ack = gpio_siox_irq_ack;
- ddata->ichip.irq_mask = gpio_siox_irq_mask;
- ddata->ichip.irq_unmask = gpio_siox_irq_unmask;
- ddata->ichip.irq_set_type = gpio_siox_irq_set_type;
-
- girq = &ddata->gchip.irq;
- girq->chip = &ddata->ichip;
+ gc = &ddata->gchip;
+ gc->base = -1;
+ gc->can_sleep = 1;
+ gc->parent = dev;
+ gc->owner = THIS_MODULE;
+ gc->get = gpio_siox_get;
+ gc->set = gpio_siox_set;
+ gc->direction_input = gpio_siox_direction_input;
+ gc->direction_output = gpio_siox_direction_output;
+ gc->get_direction = gpio_siox_get_direction;
+ gc->ngpio = 20;
+
+ girq = &gc->irq;
+ gpio_irq_chip_set_chip(girq, &gpio_siox_irq_chip);
girq->default_type = IRQ_TYPE_NONE;
girq->handler = handle_level_irq;
girq->threaded = true;

- ret = devm_gpiochip_add_data(dev, &ddata->gchip, NULL);
+ ret = devm_gpiochip_add_data(dev, gc, ddata);
if (ret)
dev_err(dev, "Failed to register gpio chip (%d)\n", ret);


--
2.34.1