gpio: mockup: add a dummy irqchip

Setup a dummy irqchip that will allow us to inject line events for
testing purposes.

Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
This commit is contained in:
Bartosz Golaszewski 2017-02-06 15:11:07 +01:00 committed by Linus Walleij
parent 8a68ea00a6
commit e2ff740895
2 changed files with 81 additions and 0 deletions

View File

@ -298,6 +298,8 @@ config GPIO_MOCKUP
tristate "GPIO Testing Driver"
depends on GPIOLIB && SYSFS
select GPIO_SYSFS
select GPIOLIB_IRQCHIP
select IRQ_WORK
help
This enables GPIO Testing driver, which provides a way to test GPIO
subsystem through sysfs(or char device) and debugfs. GPIO_SYSFS

View File

@ -16,6 +16,9 @@
#include <linux/gpio/driver.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/irq_work.h>
#define GPIO_MOCKUP_NAME "gpio-mockup"
#define GPIO_MOCKUP_MAX_GC 10
@ -35,9 +38,15 @@ struct gpio_mockup_line_status {
bool value;
};
struct gpio_mockup_irq_context {
struct irq_work work;
int irq;
};
struct gpio_mockup_chip {
struct gpio_chip gc;
struct gpio_mockup_line_status *lines;
struct gpio_mockup_irq_context irq_ctx;
};
static int gpio_mockup_ranges[GPIO_MOCKUP_MAX_GC << 1];
@ -115,6 +124,57 @@ static int gpio_mockup_name_lines(struct device *dev,
return 0;
}
static int gpio_mockup_to_irq(struct gpio_chip *chip, unsigned int offset)
{
return chip->irq_base + offset;
}
/*
* While we should generally support irqmask and irqunmask, this driver is
* for testing purposes only so we don't care.
*/
static void gpio_mockup_irqmask(struct irq_data *d) { }
static void gpio_mockup_irqunmask(struct irq_data *d) { }
static struct irq_chip gpio_mockup_irqchip = {
.name = GPIO_MOCKUP_NAME,
.irq_mask = gpio_mockup_irqmask,
.irq_unmask = gpio_mockup_irqunmask,
};
static void gpio_mockup_handle_irq(struct irq_work *work)
{
struct gpio_mockup_irq_context *irq_ctx;
irq_ctx = container_of(work, struct gpio_mockup_irq_context, work);
handle_simple_irq(irq_to_desc(irq_ctx->irq));
}
static int gpio_mockup_irqchip_setup(struct device *dev,
struct gpio_mockup_chip *chip)
{
struct gpio_chip *gc = &chip->gc;
int irq_base, i;
irq_base = irq_alloc_descs(-1, 0, gc->ngpio, 0);
if (irq_base < 0)
return irq_base;
gc->irq_base = irq_base;
gc->irqchip = &gpio_mockup_irqchip;
for (i = 0; i < gc->ngpio; i++) {
irq_set_chip(irq_base + i, gc->irqchip);
irq_set_handler(irq_base + i, &handle_simple_irq);
irq_modify_status(irq_base + i,
IRQ_NOREQUEST | IRQ_NOAUTOEN, IRQ_NOPROBE);
}
init_irq_work(&chip->irq_ctx.work, gpio_mockup_handle_irq);
return 0;
}
static int gpio_mockup_add(struct device *dev,
struct gpio_mockup_chip *chip,
const char *name, int base, int ngpio)
@ -132,6 +192,7 @@ static int gpio_mockup_add(struct device *dev,
gc->direction_output = gpio_mockup_dirout;
gc->direction_input = gpio_mockup_dirin;
gc->get_direction = gpio_mockup_get_direction;
gc->to_irq = gpio_mockup_to_irq;
chip->lines = devm_kzalloc(dev, sizeof(*chip->lines) * gc->ngpio,
GFP_KERNEL);
@ -144,6 +205,10 @@ static int gpio_mockup_add(struct device *dev,
return ret;
}
ret = gpio_mockup_irqchip_setup(dev, chip);
if (ret)
return ret;
return devm_gpiochip_add_data(dev, &chip->gc, chip);
}
@ -200,11 +265,25 @@ static int gpio_mockup_probe(struct platform_device *pdev)
return 0;
}
static int gpio_mockup_remove(struct platform_device *pdev)
{
struct gpio_mockup_chip *chips;
int i;
chips = platform_get_drvdata(pdev);
for (i = 0; i < gpio_mockup_params_nr >> 1; i++)
irq_free_descs(chips[i].gc.irq_base, chips[i].gc.ngpio);
return 0;
}
static struct platform_driver gpio_mockup_driver = {
.driver = {
.name = GPIO_MOCKUP_NAME,
},
.probe = gpio_mockup_probe,
.remove = gpio_mockup_remove,
};
static struct platform_device *pdev;