[PATCH 5/5] gpio: mockup: don't access internal GPIOLIB structures

From: Bartosz Golaszewski
Date: Thu Sep 07 2023 - 11:30:05 EST


From: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>

Don't include gpiolib.h. Track the request status of lines locally
instead. In order to retrieve the device name use the fact that
gpio-mockup supports only a single GPIO device per platform device and
call device_find_any_child().

Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx>
---
drivers/gpio/gpio-mockup.c | 39 +++++++++++++++++++++++++++++---------
1 file changed, 30 insertions(+), 9 deletions(-)

diff --git a/drivers/gpio/gpio-mockup.c b/drivers/gpio/gpio-mockup.c
index 44684ff4462f..4870e267a402 100644
--- a/drivers/gpio/gpio-mockup.c
+++ b/drivers/gpio/gpio-mockup.c
@@ -11,6 +11,7 @@

#include <linux/cleanup.h>
#include <linux/debugfs.h>
+#include <linux/device.h>
#include <linux/gpio/driver.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
@@ -25,8 +26,6 @@
#include <linux/string_helpers.h>
#include <linux/uaccess.h>

-#include "gpiolib.h"
-
#define GPIO_MOCKUP_MAX_GC 10
/*
* We're storing two values per chip: the GPIO base and the number
@@ -42,11 +41,13 @@
* @value: Configures status of the gpio as 0(low) or 1(high)
* @pull: Configures the current pull of the GPIO as 0 (pull-down) or
* 1 (pull-up)
+ * @requested: Request status of this GPIO
*/
struct gpio_mockup_line_status {
int dir;
int value;
int pull;
+ bool requested;
};

struct gpio_mockup_chip {
@@ -146,14 +147,12 @@ static void gpio_mockup_set_multiple(struct gpio_chip *gc,
static int gpio_mockup_apply_pull(struct gpio_mockup_chip *chip,
unsigned int offset, int value)
{
- struct gpio_chip *gc = &chip->gc;
- struct gpio_desc *desc = gpiochip_get_desc(gc, offset);
+ struct gpio_mockup_line_status *line = &chip->lines[offset];
int curr, irq, irq_type, ret = 0;

guard(mutex)(&chip->lock);

- if (test_bit(FLAG_REQUESTED, &desc->flags) &&
- !test_bit(FLAG_IS_OUT, &desc->flags)) {
+ if (line->requested && line->dir == GPIO_LINE_DIRECTION_IN) {
curr = __gpio_mockup_get(chip, offset);
if (curr == value)
goto out;
@@ -181,8 +180,7 @@ static int gpio_mockup_apply_pull(struct gpio_mockup_chip *chip,

set_value:
/* Change the value unless we're actively driving the line. */
- if (!test_bit(FLAG_REQUESTED, &desc->flags) ||
- !test_bit(FLAG_IS_OUT, &desc->flags))
+ if (!line->requested || line->dir == GPIO_LINE_DIRECTION_IN)
__gpio_mockup_set(chip, offset, value);

out:
@@ -247,10 +245,23 @@ static int gpio_mockup_to_irq(struct gpio_chip *gc, unsigned int offset)
return irq_create_mapping(chip->irq_sim_domain, offset);
}

+static int gpio_mockup_request(struct gpio_chip *gc, unsigned int offset)
+{
+ struct gpio_mockup_chip *chip = gpiochip_get_data(gc);
+
+ scoped_guard(mutex, &chip->lock)
+ chip->lines[offset].requested = true;
+
+ return 0;
+}
+
static void gpio_mockup_free(struct gpio_chip *gc, unsigned int offset)
{
struct gpio_mockup_chip *chip = gpiochip_get_data(gc);

+ guard(mutex)(&chip->lock);
+
+ chip->lines[offset].requested = false;
__gpio_mockup_set(chip, offset, chip->lines[offset].pull);
}

@@ -343,6 +354,7 @@ static const struct file_operations gpio_mockup_debugfs_ops = {
static void gpio_mockup_debugfs_setup(struct device *dev,
struct gpio_mockup_chip *chip)
{
+ struct device *child __free(put_device) = NULL;
struct gpio_mockup_dbgfs_private *priv;
struct gpio_chip *gc;
const char *devname;
@@ -350,8 +362,16 @@ static void gpio_mockup_debugfs_setup(struct device *dev,
int i;

gc = &chip->gc;
- devname = dev_name(&gc->gpiodev->dev);

+ /*
+ * There can only be a single GPIO device per platform device in
+ * gpio-mockup so using device_find_any_child() is OK.
+ */
+ child = device_find_any_child(dev);
+ if (!child)
+ return;
+
+ devname = dev_name(child);
chip->dbg_dir = debugfs_create_dir(devname, gpio_mockup_dbg_dir);

for (i = 0; i < gc->ngpio; i++) {
@@ -435,6 +455,7 @@ static int gpio_mockup_probe(struct platform_device *pdev)
gc->get_direction = gpio_mockup_get_direction;
gc->set_config = gpio_mockup_set_config;
gc->to_irq = gpio_mockup_to_irq;
+ gc->request = gpio_mockup_request;
gc->free = gpio_mockup_free;

chip->lines = devm_kcalloc(dev, gc->ngpio,
--
2.39.2