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-rw-r--r--drivers/gpio/gpio-crystalcove.c2
-rw-r--r--drivers/gpio/gpio-lpc32xx.c1
-rw-r--r--drivers/gpio/gpio-tangier.c9
-rw-r--r--drivers/gpio/gpio-tegra186.c20
-rw-r--r--drivers/gpio/gpio-wcove.c2
-rw-r--r--drivers/gpio/gpiolib-cdev.c66
-rw-r--r--drivers/gpio/gpiolib.c61
-rw-r--r--drivers/gpio/gpiolib.h17
8 files changed, 118 insertions, 60 deletions
diff --git a/drivers/gpio/gpio-crystalcove.c b/drivers/gpio/gpio-crystalcove.c
index 1ee62cd58582..25db014494a4 100644
--- a/drivers/gpio/gpio-crystalcove.c
+++ b/drivers/gpio/gpio-crystalcove.c
@@ -92,7 +92,7 @@ static inline int to_reg(int gpio, enum ctrl_register reg_type)
case 0x5e:
return GPIOPANELCTL;
default:
- return -EOPNOTSUPP;
+ return -ENOTSUPP;
}
}
diff --git a/drivers/gpio/gpio-lpc32xx.c b/drivers/gpio/gpio-lpc32xx.c
index 5ef8af824980..c097e310c9e8 100644
--- a/drivers/gpio/gpio-lpc32xx.c
+++ b/drivers/gpio/gpio-lpc32xx.c
@@ -529,6 +529,7 @@ static const struct of_device_id lpc32xx_gpio_of_match[] = {
{ .compatible = "nxp,lpc3220-gpio", },
{ },
};
+MODULE_DEVICE_TABLE(of, lpc32xx_gpio_of_match);
static struct platform_driver lpc32xx_gpio_driver = {
.driver = {
diff --git a/drivers/gpio/gpio-tangier.c b/drivers/gpio/gpio-tangier.c
index b75e0b12087a..4b29abafecf6 100644
--- a/drivers/gpio/gpio-tangier.c
+++ b/drivers/gpio/gpio-tangier.c
@@ -195,7 +195,8 @@ static int tng_gpio_set_config(struct gpio_chip *chip, unsigned int offset,
static void tng_irq_ack(struct irq_data *d)
{
- struct tng_gpio *priv = irq_data_get_irq_chip_data(d);
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct tng_gpio *priv = gpiochip_get_data(gc);
irq_hw_number_t gpio = irqd_to_hwirq(d);
void __iomem *gisr;
u8 shift;
@@ -227,7 +228,8 @@ static void tng_irq_unmask_mask(struct tng_gpio *priv, u32 gpio, bool unmask)
static void tng_irq_mask(struct irq_data *d)
{
- struct tng_gpio *priv = irq_data_get_irq_chip_data(d);
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct tng_gpio *priv = gpiochip_get_data(gc);
irq_hw_number_t gpio = irqd_to_hwirq(d);
tng_irq_unmask_mask(priv, gpio, false);
@@ -236,7 +238,8 @@ static void tng_irq_mask(struct irq_data *d)
static void tng_irq_unmask(struct irq_data *d)
{
- struct tng_gpio *priv = irq_data_get_irq_chip_data(d);
+ struct gpio_chip *gc = irq_data_get_irq_chip_data(d);
+ struct tng_gpio *priv = gpiochip_get_data(gc);
irq_hw_number_t gpio = irqd_to_hwirq(d);
gpiochip_enable_irq(&priv->chip, gpio);
diff --git a/drivers/gpio/gpio-tegra186.c b/drivers/gpio/gpio-tegra186.c
index d87dd06db40d..9130c691a2dd 100644
--- a/drivers/gpio/gpio-tegra186.c
+++ b/drivers/gpio/gpio-tegra186.c
@@ -36,12 +36,6 @@
#define TEGRA186_GPIO_SCR_SEC_REN BIT(27)
#define TEGRA186_GPIO_SCR_SEC_G1W BIT(9)
#define TEGRA186_GPIO_SCR_SEC_G1R BIT(1)
-#define TEGRA186_GPIO_FULL_ACCESS (TEGRA186_GPIO_SCR_SEC_WEN | \
- TEGRA186_GPIO_SCR_SEC_REN | \
- TEGRA186_GPIO_SCR_SEC_G1R | \
- TEGRA186_GPIO_SCR_SEC_G1W)
-#define TEGRA186_GPIO_SCR_SEC_ENABLE (TEGRA186_GPIO_SCR_SEC_WEN | \
- TEGRA186_GPIO_SCR_SEC_REN)
/* control registers */
#define TEGRA186_GPIO_ENABLE_CONFIG 0x00
@@ -177,10 +171,18 @@ static inline bool tegra186_gpio_is_accessible(struct tegra_gpio *gpio, unsigned
value = __raw_readl(secure + TEGRA186_GPIO_SCR);
- if ((value & TEGRA186_GPIO_SCR_SEC_ENABLE) == 0)
- return true;
+ /*
+ * When SCR_SEC_[R|W]EN is unset, then we have full read/write access to all the
+ * registers for given GPIO pin.
+ * When SCR_SEC[R|W]EN is set, then there is need to further check the accompanying
+ * SCR_SEC_G1[R|W] bit to determine read/write access to all the registers for given
+ * GPIO pin.
+ */
- if ((value & TEGRA186_GPIO_FULL_ACCESS) == TEGRA186_GPIO_FULL_ACCESS)
+ if (((value & TEGRA186_GPIO_SCR_SEC_REN) == 0 ||
+ ((value & TEGRA186_GPIO_SCR_SEC_REN) && (value & TEGRA186_GPIO_SCR_SEC_G1R))) &&
+ ((value & TEGRA186_GPIO_SCR_SEC_WEN) == 0 ||
+ ((value & TEGRA186_GPIO_SCR_SEC_WEN) && (value & TEGRA186_GPIO_SCR_SEC_G1W))))
return true;
return false;
diff --git a/drivers/gpio/gpio-wcove.c b/drivers/gpio/gpio-wcove.c
index c18b6b47384f..94ca9d03c094 100644
--- a/drivers/gpio/gpio-wcove.c
+++ b/drivers/gpio/gpio-wcove.c
@@ -104,7 +104,7 @@ static inline int to_reg(int gpio, enum ctrl_register type)
unsigned int reg = type == CTRL_IN ? GPIO_IN_CTRL_BASE : GPIO_OUT_CTRL_BASE;
if (gpio >= WCOVE_GPIO_NUM)
- return -EOPNOTSUPP;
+ return -ENOTSUPP;
return reg + gpio;
}
diff --git a/drivers/gpio/gpiolib-cdev.c b/drivers/gpio/gpiolib-cdev.c
index fa9635610251..9dad67ea2597 100644
--- a/drivers/gpio/gpiolib-cdev.c
+++ b/drivers/gpio/gpiolib-cdev.c
@@ -728,6 +728,25 @@ static u32 line_event_id(int level)
GPIO_V2_LINE_EVENT_FALLING_EDGE;
}
+static inline char *make_irq_label(const char *orig)
+{
+ char *new;
+
+ if (!orig)
+ return NULL;
+
+ new = kstrdup_and_replace(orig, '/', ':', GFP_KERNEL);
+ if (!new)
+ return ERR_PTR(-ENOMEM);
+
+ return new;
+}
+
+static inline void free_irq_label(const char *label)
+{
+ kfree(label);
+}
+
#ifdef CONFIG_HTE
static enum hte_return process_hw_ts_thread(void *p)
@@ -1015,6 +1034,7 @@ static int debounce_setup(struct line *line, unsigned int debounce_period_us)
{
unsigned long irqflags;
int ret, level, irq;
+ char *label;
/* try hardware */
ret = gpiod_set_debounce(line->desc, debounce_period_us);
@@ -1037,11 +1057,17 @@ static int debounce_setup(struct line *line, unsigned int debounce_period_us)
if (irq < 0)
return -ENXIO;
+ label = make_irq_label(line->req->label);
+ if (IS_ERR(label))
+ return -ENOMEM;
+
irqflags = IRQF_TRIGGER_FALLING | IRQF_TRIGGER_RISING;
ret = request_irq(irq, debounce_irq_handler, irqflags,
- line->req->label, line);
- if (ret)
+ label, line);
+ if (ret) {
+ free_irq_label(label);
return ret;
+ }
line->irq = irq;
} else {
ret = hte_edge_setup(line, GPIO_V2_LINE_FLAG_EDGE_BOTH);
@@ -1083,16 +1109,6 @@ static u32 gpio_v2_line_config_debounce_period(struct gpio_v2_line_config *lc,
return 0;
}
-static inline char *make_irq_label(const char *orig)
-{
- return kstrdup_and_replace(orig, '/', ':', GFP_KERNEL);
-}
-
-static inline void free_irq_label(const char *label)
-{
- kfree(label);
-}
-
static void edge_detector_stop(struct line *line)
{
if (line->irq) {
@@ -1158,8 +1174,8 @@ static int edge_detector_setup(struct line *line,
irqflags |= IRQF_ONESHOT;
label = make_irq_label(line->req->label);
- if (!label)
- return -ENOMEM;
+ if (IS_ERR(label))
+ return PTR_ERR(label);
/* Request a thread to read the events */
ret = request_threaded_irq(irq, edge_irq_handler, edge_irq_thread,
@@ -1177,6 +1193,8 @@ static int edge_detector_update(struct line *line,
struct gpio_v2_line_config *lc,
unsigned int line_idx, u64 edflags)
{
+ u64 eflags;
+ int ret;
u64 active_edflags = READ_ONCE(line->edflags);
unsigned int debounce_period_us =
gpio_v2_line_config_debounce_period(lc, line_idx);
@@ -1188,6 +1206,18 @@ static int edge_detector_update(struct line *line,
/* sw debounced and still will be...*/
if (debounce_period_us && READ_ONCE(line->sw_debounced)) {
line_set_debounce_period(line, debounce_period_us);
+ /*
+ * ensure event fifo is initialised if edge detection
+ * is now enabled.
+ */
+ eflags = edflags & GPIO_V2_LINE_EDGE_FLAGS;
+ if (eflags && !kfifo_initialized(&line->req->events)) {
+ ret = kfifo_alloc(&line->req->events,
+ line->req->event_buffer_size,
+ GFP_KERNEL);
+ if (ret)
+ return ret;
+ }
return 0;
}
@@ -2217,8 +2247,8 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
goto out_free_le;
label = make_irq_label(le->label);
- if (!label) {
- ret = -ENOMEM;
+ if (IS_ERR(label)) {
+ ret = PTR_ERR(label);
goto out_free_le;
}
@@ -2335,7 +2365,7 @@ static void gpio_desc_to_lineinfo(struct gpio_desc *desc,
dflags = READ_ONCE(desc->flags);
- scoped_guard(srcu, &desc->srcu) {
+ scoped_guard(srcu, &desc->gdev->desc_srcu) {
label = gpiod_get_label(desc);
if (label && test_bit(FLAG_REQUESTED, &dflags))
strscpy(info->consumer, label,
@@ -2783,11 +2813,11 @@ static int gpio_chrdev_release(struct inode *inode, struct file *file)
struct gpio_chardev_data *cdev = file->private_data;
struct gpio_device *gdev = cdev->gdev;
- bitmap_free(cdev->watched_lines);
blocking_notifier_chain_unregister(&gdev->device_notifier,
&cdev->device_unregistered_nb);
blocking_notifier_chain_unregister(&gdev->line_state_notifier,
&cdev->lineinfo_changed_nb);
+ bitmap_free(cdev->watched_lines);
gpio_device_put(gdev);
kfree(cdev);
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 59ccf9a3e153..fa50db0c3605 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -101,6 +101,7 @@ static bool gpiolib_initialized;
const char *gpiod_get_label(struct gpio_desc *desc)
{
+ struct gpio_desc_label *label;
unsigned long flags;
flags = READ_ONCE(desc->flags);
@@ -108,23 +109,36 @@ const char *gpiod_get_label(struct gpio_desc *desc)
!test_bit(FLAG_REQUESTED, &flags))
return "interrupt";
- return test_bit(FLAG_REQUESTED, &flags) ?
- srcu_dereference(desc->label, &desc->srcu) : NULL;
+ if (!test_bit(FLAG_REQUESTED, &flags))
+ return NULL;
+
+ label = srcu_dereference_check(desc->label, &desc->gdev->desc_srcu,
+ srcu_read_lock_held(&desc->gdev->desc_srcu));
+
+ return label->str;
+}
+
+static void desc_free_label(struct rcu_head *rh)
+{
+ kfree(container_of(rh, struct gpio_desc_label, rh));
}
static int desc_set_label(struct gpio_desc *desc, const char *label)
{
- const char *new = NULL, *old;
+ struct gpio_desc_label *new = NULL, *old;
if (label) {
- new = kstrdup_const(label, GFP_KERNEL);
+ new = kzalloc(struct_size(new, str, strlen(label) + 1),
+ GFP_KERNEL);
if (!new)
return -ENOMEM;
+
+ strcpy(new->str, label);
}
old = rcu_replace_pointer(desc->label, new, 1);
- synchronize_srcu(&desc->srcu);
- kfree_const(old);
+ if (old)
+ call_srcu(&desc->gdev->desc_srcu, &old->rh, desc_free_label);
return 0;
}
@@ -695,10 +709,10 @@ EXPORT_SYMBOL_GPL(gpiochip_line_is_valid);
static void gpiodev_release(struct device *dev)
{
struct gpio_device *gdev = to_gpio_device(dev);
- unsigned int i;
- for (i = 0; i < gdev->ngpio; i++)
- cleanup_srcu_struct(&gdev->descs[i].srcu);
+ /* Call pending kfree()s for descriptor labels. */
+ synchronize_srcu(&gdev->desc_srcu);
+ cleanup_srcu_struct(&gdev->desc_srcu);
ida_free(&gpio_ida, gdev->id);
kfree_const(gdev->label);
@@ -975,6 +989,10 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
if (ret)
goto err_remove_from_list;
+ ret = init_srcu_struct(&gdev->desc_srcu);
+ if (ret)
+ goto err_cleanup_gdev_srcu;
+
#ifdef CONFIG_PINCTRL
INIT_LIST_HEAD(&gdev->pin_ranges);
#endif
@@ -982,23 +1000,19 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
if (gc->names) {
ret = gpiochip_set_desc_names(gc);
if (ret)
- goto err_cleanup_gdev_srcu;
+ goto err_cleanup_desc_srcu;
}
ret = gpiochip_set_names(gc);
if (ret)
- goto err_cleanup_gdev_srcu;
+ goto err_cleanup_desc_srcu;
ret = gpiochip_init_valid_mask(gc);
if (ret)
- goto err_cleanup_gdev_srcu;
+ goto err_cleanup_desc_srcu;
for (desc_index = 0; desc_index < gc->ngpio; desc_index++) {
struct gpio_desc *desc = &gdev->descs[desc_index];
- ret = init_srcu_struct(&desc->srcu);
- if (ret)
- goto err_cleanup_desc_srcu;
-
if (gc->get_direction && gpiochip_line_is_valid(gc, desc_index)) {
assign_bit(FLAG_IS_OUT,
&desc->flags, !gc->get_direction(gc, desc_index));
@@ -1010,7 +1024,7 @@ int gpiochip_add_data_with_key(struct gpio_chip *gc, void *data,
ret = of_gpiochip_add(gc);
if (ret)
- goto err_cleanup_desc_srcu;
+ goto err_free_valid_mask;
ret = gpiochip_add_pin_ranges(gc);
if (ret)
@@ -1057,10 +1071,10 @@ err_free_hogs:
gpiochip_remove_pin_ranges(gc);
err_remove_of_chip:
of_gpiochip_remove(gc);
-err_cleanup_desc_srcu:
- while (desc_index--)
- cleanup_srcu_struct(&gdev->descs[desc_index].srcu);
+err_free_valid_mask:
gpiochip_free_valid_mask(gc);
+err_cleanup_desc_srcu:
+ cleanup_srcu_struct(&gdev->desc_srcu);
err_cleanup_gdev_srcu:
cleanup_srcu_struct(&gdev->srcu);
err_remove_from_list:
@@ -1175,6 +1189,9 @@ struct gpio_device *gpio_device_find(const void *data,
list_for_each_entry_srcu(gdev, &gpio_devices, list,
srcu_read_lock_held(&gpio_devices_srcu)) {
+ if (!device_is_registered(&gdev->dev))
+ continue;
+
guard(srcu)(&gdev->srcu);
gc = srcu_dereference(gdev->chip, &gdev->srcu);
@@ -2387,7 +2404,7 @@ char *gpiochip_dup_line_label(struct gpio_chip *gc, unsigned int offset)
if (!test_bit(FLAG_REQUESTED, &desc->flags))
return NULL;
- guard(srcu)(&desc->srcu);
+ guard(srcu)(&desc->gdev->desc_srcu);
label = kstrdup(gpiod_get_label(desc), GFP_KERNEL);
if (!label)
@@ -4778,7 +4795,7 @@ static void gpiolib_dbg_show(struct seq_file *s, struct gpio_device *gdev)
}
for_each_gpio_desc(gc, desc) {
- guard(srcu)(&desc->srcu);
+ guard(srcu)(&desc->gdev->desc_srcu);
if (test_bit(FLAG_REQUESTED, &desc->flags)) {
gpiod_get_direction(desc);
is_out = test_bit(FLAG_IS_OUT, &desc->flags);
diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h
index f67d5991ab1c..8e0e211ebf08 100644
--- a/drivers/gpio/gpiolib.h
+++ b/drivers/gpio/gpiolib.h
@@ -31,6 +31,7 @@
* @chip: pointer to the corresponding gpiochip, holding static
* data for this device
* @descs: array of ngpio descriptors.
+ * @desc_srcu: ensures consistent state of GPIO descriptors exposed to users
* @ngpio: the number of GPIO lines on this GPIO device, equal to the size
* of the @descs array.
* @can_sleep: indicate whether the GPIO chip driver's callbacks can sleep
@@ -61,6 +62,7 @@ struct gpio_device {
struct module *owner;
struct gpio_chip __rcu *chip;
struct gpio_desc *descs;
+ struct srcu_struct desc_srcu;
int base;
u16 ngpio;
bool can_sleep;
@@ -137,6 +139,11 @@ int gpiod_set_transitory(struct gpio_desc *desc, bool transitory);
void gpiod_line_state_notify(struct gpio_desc *desc, unsigned long action);
+struct gpio_desc_label {
+ struct rcu_head rh;
+ char str[];
+};
+
/**
* struct gpio_desc - Opaque descriptor for a GPIO
*
@@ -145,7 +152,6 @@ void gpiod_line_state_notify(struct gpio_desc *desc, unsigned long action);
* @label: Name of the consumer
* @name: Line name
* @hog: Pointer to the device node that hogs this line (if any)
- * @srcu: SRCU struct protecting the label pointer.
*
* These are obtained using gpiod_get() and are preferable to the old
* integer-based handles.
@@ -177,13 +183,12 @@ struct gpio_desc {
#define FLAG_EVENT_CLOCK_HTE 19 /* GPIO CDEV reports hardware timestamps in events */
/* Connection label */
- const char __rcu *label;
+ struct gpio_desc_label __rcu *label;
/* Name of the GPIO */
const char *name;
#ifdef CONFIG_OF_DYNAMIC
struct device_node *hog;
#endif
- struct srcu_struct srcu;
};
#define gpiod_not_found(desc) (IS_ERR(desc) && PTR_ERR(desc) == -ENOENT)
@@ -251,7 +256,7 @@ static inline int gpio_chip_hwgpio(const struct gpio_desc *desc)
#define gpiod_err(desc, fmt, ...) \
do { \
- scoped_guard(srcu, &desc->srcu) { \
+ scoped_guard(srcu, &desc->gdev->desc_srcu) { \
pr_err("gpio-%d (%s): " fmt, desc_to_gpio(desc), \
gpiod_get_label(desc) ? : "?", ##__VA_ARGS__); \
} \
@@ -259,7 +264,7 @@ do { \
#define gpiod_warn(desc, fmt, ...) \
do { \
- scoped_guard(srcu, &desc->srcu) { \
+ scoped_guard(srcu, &desc->gdev->desc_srcu) { \
pr_warn("gpio-%d (%s): " fmt, desc_to_gpio(desc), \
gpiod_get_label(desc) ? : "?", ##__VA_ARGS__); \
} \
@@ -267,7 +272,7 @@ do { \
#define gpiod_dbg(desc, fmt, ...) \
do { \
- scoped_guard(srcu, &desc->srcu) { \
+ scoped_guard(srcu, &desc->gdev->desc_srcu) { \
pr_debug("gpio-%d (%s): " fmt, desc_to_gpio(desc), \
gpiod_get_label(desc) ? : "?", ##__VA_ARGS__); \
} \