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path: root/drivers/gpio/gpiolib.c
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Diffstat (limited to 'drivers/gpio/gpiolib.c')
-rw-r--r--drivers/gpio/gpiolib.c78
1 files changed, 55 insertions, 23 deletions
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 21062cb6b85f..f0777a7a4305 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -206,6 +206,14 @@ int gpiod_get_direction(struct gpio_desc *desc)
chip = gpiod_to_chip(desc);
offset = gpio_chip_hwgpio(desc);
+ /*
+ * Open drain emulation using input mode may incorrectly report
+ * input here, fix that up.
+ */
+ if (test_bit(FLAG_OPEN_DRAIN, &desc->flags) &&
+ test_bit(FLAG_IS_OUT, &desc->flags))
+ return 0;
+
if (!chip->get_direction)
return status;
@@ -444,12 +452,23 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip)
struct linehandle_state *lh;
struct file *file;
int fd, i, count = 0, ret;
+ u32 lflags;
if (copy_from_user(&handlereq, ip, sizeof(handlereq)))
return -EFAULT;
if ((handlereq.lines == 0) || (handlereq.lines > GPIOHANDLES_MAX))
return -EINVAL;
+ lflags = handlereq.flags;
+
+ /*
+ * Do not allow both INPUT & OUTPUT flags to be set as they are
+ * contradictory.
+ */
+ if ((lflags & GPIOHANDLE_REQUEST_INPUT) &&
+ (lflags & GPIOHANDLE_REQUEST_OUTPUT))
+ return -EINVAL;
+
lh = kzalloc(sizeof(*lh), GFP_KERNEL);
if (!lh)
return -ENOMEM;
@@ -470,7 +489,6 @@ static int linehandle_create(struct gpio_device *gdev, void __user *ip)
/* Request each GPIO */
for (i = 0; i < handlereq.lines; i++) {
u32 offset = handlereq.lineoffsets[i];
- u32 lflags = handlereq.flags;
struct gpio_desc *desc;
if (offset >= gdev->ngpio) {
@@ -805,7 +823,9 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
}
/* This is just wrong: we don't look for events on output lines */
- if (lflags & GPIOHANDLE_REQUEST_OUTPUT) {
+ if ((lflags & GPIOHANDLE_REQUEST_OUTPUT) ||
+ (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN) ||
+ (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)) {
ret = -EINVAL;
goto out_free_label;
}
@@ -819,10 +839,6 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
if (lflags & GPIOHANDLE_REQUEST_ACTIVE_LOW)
set_bit(FLAG_ACTIVE_LOW, &desc->flags);
- if (lflags & GPIOHANDLE_REQUEST_OPEN_DRAIN)
- set_bit(FLAG_OPEN_DRAIN, &desc->flags);
- if (lflags & GPIOHANDLE_REQUEST_OPEN_SOURCE)
- set_bit(FLAG_OPEN_SOURCE, &desc->flags);
ret = gpiod_direction_input(desc);
if (ret)
@@ -835,9 +851,11 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
}
if (eflags & GPIOEVENT_REQUEST_RISING_EDGE)
- irqflags |= IRQF_TRIGGER_RISING;
+ irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
+ IRQF_TRIGGER_FALLING : IRQF_TRIGGER_RISING;
if (eflags & GPIOEVENT_REQUEST_FALLING_EDGE)
- irqflags |= IRQF_TRIGGER_FALLING;
+ irqflags |= test_bit(FLAG_ACTIVE_LOW, &desc->flags) ?
+ IRQF_TRIGGER_RISING : IRQF_TRIGGER_FALLING;
irqflags |= IRQF_ONESHOT;
irqflags |= IRQF_SHARED;
@@ -969,9 +987,11 @@ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
lineinfo.flags |= GPIOLINE_FLAG_ACTIVE_LOW;
if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
- lineinfo.flags |= GPIOLINE_FLAG_OPEN_DRAIN;
+ lineinfo.flags |= (GPIOLINE_FLAG_OPEN_DRAIN |
+ GPIOLINE_FLAG_IS_OUT);
if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
- lineinfo.flags |= GPIOLINE_FLAG_OPEN_SOURCE;
+ lineinfo.flags |= (GPIOLINE_FLAG_OPEN_SOURCE |
+ GPIOLINE_FLAG_IS_OUT);
if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))
return -EFAULT;
@@ -2317,8 +2337,10 @@ static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value)
if (!ret)
goto set_output_value;
/* Emulate open drain by not actively driving the line high */
- if (val)
- return gpiod_direction_input(desc);
+ if (val) {
+ ret = gpiod_direction_input(desc);
+ goto set_output_flag;
+ }
}
else if (test_bit(FLAG_OPEN_SOURCE, &desc->flags)) {
ret = gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc),
@@ -2326,8 +2348,10 @@ static int _gpiod_direction_output_raw(struct gpio_desc *desc, int value)
if (!ret)
goto set_output_value;
/* Emulate open source by not actively driving the line low */
- if (!val)
- return gpiod_direction_input(desc);
+ if (!val) {
+ ret = gpiod_direction_input(desc);
+ goto set_output_flag;
+ }
} else {
gpio_set_drive_single_ended(gc, gpio_chip_hwgpio(desc),
PIN_CONFIG_DRIVE_PUSH_PULL);
@@ -2347,6 +2371,17 @@ set_output_value:
trace_gpio_value(desc_to_gpio(desc), 0, val);
trace_gpio_direction(desc_to_gpio(desc), 0, ret);
return ret;
+
+set_output_flag:
+ /*
+ * When emulating open-source or open-drain functionalities by not
+ * actively driving the line (setting mode to input) we still need to
+ * set the IS_OUT flag or otherwise we won't be able to set the line
+ * value anymore.
+ */
+ if (ret == 0)
+ set_bit(FLAG_IS_OUT, &desc->flags);
+ return ret;
}
/**
@@ -2480,7 +2515,7 @@ static int _gpiod_get_raw_value(const struct gpio_desc *desc)
int gpiod_get_raw_value(const struct gpio_desc *desc)
{
VALIDATE_DESC(desc);
- /* Should be using gpio_get_value_cansleep() */
+ /* Should be using gpiod_get_raw_value_cansleep() */
WARN_ON(desc->gdev->chip->can_sleep);
return _gpiod_get_raw_value(desc);
}
@@ -2501,7 +2536,7 @@ int gpiod_get_value(const struct gpio_desc *desc)
int value;
VALIDATE_DESC(desc);
- /* Should be using gpio_get_value_cansleep() */
+ /* Should be using gpiod_get_value_cansleep() */
WARN_ON(desc->gdev->chip->can_sleep);
value = _gpiod_get_raw_value(desc);
@@ -2528,8 +2563,6 @@ static void _gpio_set_open_drain_value(struct gpio_desc *desc, bool value)
if (value) {
err = chip->direction_input(chip, offset);
- if (!err)
- clear_bit(FLAG_IS_OUT, &desc->flags);
} else {
err = chip->direction_output(chip, offset, 0);
if (!err)
@@ -2559,8 +2592,6 @@ static void _gpio_set_open_source_value(struct gpio_desc *desc, bool value)
set_bit(FLAG_IS_OUT, &desc->flags);
} else {
err = chip->direction_input(chip, offset);
- if (!err)
- clear_bit(FLAG_IS_OUT, &desc->flags);
}
trace_gpio_direction(desc_to_gpio(desc), !value, err);
if (err < 0)
@@ -2670,7 +2701,7 @@ void gpiod_set_array_value_complex(bool raw, bool can_sleep,
void gpiod_set_raw_value(struct gpio_desc *desc, int value)
{
VALIDATE_DESC_VOID(desc);
- /* Should be using gpiod_set_value_cansleep() */
+ /* Should be using gpiod_set_raw_value_cansleep() */
WARN_ON(desc->gdev->chip->can_sleep);
_gpiod_set_raw_value(desc, value);
}
@@ -3136,8 +3167,9 @@ static struct gpio_desc *gpiod_find(struct device *dev, const char *con_id,
if (chip->ngpio <= p->chip_hwnum) {
dev_err(dev,
- "requested GPIO %d is out of range [0..%d] for chip %s\n",
- idx, chip->ngpio, chip->label);
+ "requested GPIO %u (%u) is out of range [0..%u] for chip %s\n",
+ idx, p->chip_hwnum, chip->ngpio - 1,
+ chip->label);
return ERR_PTR(-EINVAL);
}
generated by cgit v1.2.3 (git 2.0.4) at 2024-05-30 05:46:25 +0000