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-rw-r--r--drivers/gpio/Kconfig7
-rw-r--r--drivers/gpio/Makefile1
-rw-r--r--drivers/gpio/gpio-mlxbf2.c335
-rw-r--r--drivers/gpio/gpio-mockup.c2
-rw-r--r--drivers/gpio/gpio-pxa.c4
-rw-r--r--drivers/gpio/gpio-rcar.c4
-rw-r--r--drivers/gpio/gpio-siox.c28
-rw-r--r--drivers/gpio/gpio-uniphier.c2
-rw-r--r--drivers/gpio/gpio-wcd934x.c9
-rw-r--r--drivers/gpio/gpiolib-of.c139
-rw-r--r--drivers/gpio/gpiolib-of.h2
-rw-r--r--drivers/gpio/gpiolib.c383
-rw-r--r--drivers/gpio/gpiolib.h4
-rw-r--r--include/asm-generic/gpio.h4
-rw-r--r--include/linux/gpio.h2
-rw-r--r--include/linux/gpio/consumer.h5
-rw-r--r--include/linux/kfifo.h73
-rw-r--r--include/linux/of_gpio.h9
-rw-r--r--include/uapi/linux/gpio.h30
-rw-r--r--tools/gpio/.gitignore1
-rw-r--r--tools/gpio/Build1
-rw-r--r--tools/gpio/Makefile11
-rw-r--r--tools/gpio/gpio-watch.c99
23 files changed, 1014 insertions, 141 deletions
diff --git a/drivers/gpio/Kconfig b/drivers/gpio/Kconfig
index b8013cf90064..6234ccc90e7e 100644
--- a/drivers/gpio/Kconfig
+++ b/drivers/gpio/Kconfig
@@ -1399,6 +1399,13 @@ config GPIO_MLXBF
help
Say Y here if you want GPIO support on Mellanox BlueField SoC.
+config GPIO_MLXBF2
+ tristate "Mellanox BlueField 2 SoC GPIO"
+ depends on (MELLANOX_PLATFORM && ARM64 && ACPI) || (64BIT && COMPILE_TEST)
+ select GPIO_GENERIC
+ help
+ Say Y here if you want GPIO support on Mellanox BlueField 2 SoC.
+
config GPIO_ML_IOH
tristate "OKI SEMICONDUCTOR ML7213 IOH GPIO support"
depends on X86 || COMPILE_TEST
diff --git a/drivers/gpio/Makefile b/drivers/gpio/Makefile
index 0b571264ddbc..b2cfc21a97f3 100644
--- a/drivers/gpio/Makefile
+++ b/drivers/gpio/Makefile
@@ -93,6 +93,7 @@ obj-$(CONFIG_GPIO_MENZ127) += gpio-menz127.o
obj-$(CONFIG_GPIO_MERRIFIELD) += gpio-merrifield.o
obj-$(CONFIG_GPIO_ML_IOH) += gpio-ml-ioh.o
obj-$(CONFIG_GPIO_MLXBF) += gpio-mlxbf.o
+obj-$(CONFIG_GPIO_MLXBF2) += gpio-mlxbf2.o
obj-$(CONFIG_GPIO_MM_LANTIQ) += gpio-mm-lantiq.o
obj-$(CONFIG_GPIO_MOCKUP) += gpio-mockup.o
obj-$(CONFIG_GPIO_MOXTET) += gpio-moxtet.o
diff --git a/drivers/gpio/gpio-mlxbf2.c b/drivers/gpio/gpio-mlxbf2.c
new file mode 100644
index 000000000000..7b7085050219
--- /dev/null
+++ b/drivers/gpio/gpio-mlxbf2.c
@@ -0,0 +1,335 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/acpi.h>
+#include <linux/bitfield.h>
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/gpio/driver.h>
+#include <linux/io.h>
+#include <linux/ioport.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/pm.h>
+#include <linux/resource.h>
+#include <linux/spinlock.h>
+#include <linux/types.h>
+#include <linux/version.h>
+
+/*
+ * There are 3 YU GPIO blocks:
+ * gpio[0]: HOST_GPIO0->HOST_GPIO31
+ * gpio[1]: HOST_GPIO32->HOST_GPIO63
+ * gpio[2]: HOST_GPIO64->HOST_GPIO69
+ */
+#define MLXBF2_GPIO_MAX_PINS_PER_BLOCK 32
+
+/*
+ * arm_gpio_lock register:
+ * bit[31] lock status: active if set
+ * bit[15:0] set lock
+ * The lock is enabled only if 0xd42f is written to this field
+ */
+#define YU_ARM_GPIO_LOCK_ADDR 0x2801088
+#define YU_ARM_GPIO_LOCK_SIZE 0x8
+#define YU_LOCK_ACTIVE_BIT(val) (val >> 31)
+#define YU_ARM_GPIO_LOCK_ACQUIRE 0xd42f
+#define YU_ARM_GPIO_LOCK_RELEASE 0x0
+
+/*
+ * gpio[x] block registers and their offset
+ */
+#define YU_GPIO_DATAIN 0x04
+#define YU_GPIO_MODE1 0x08
+#define YU_GPIO_MODE0 0x0c
+#define YU_GPIO_DATASET 0x14
+#define YU_GPIO_DATACLEAR 0x18
+#define YU_GPIO_MODE1_CLEAR 0x50
+#define YU_GPIO_MODE0_SET 0x54
+#define YU_GPIO_MODE0_CLEAR 0x58
+
+#ifdef CONFIG_PM
+struct mlxbf2_gpio_context_save_regs {
+ u32 gpio_mode0;
+ u32 gpio_mode1;
+};
+#endif
+
+/* BlueField-2 gpio block context structure. */
+struct mlxbf2_gpio_context {
+ struct gpio_chip gc;
+
+ /* YU GPIO blocks address */
+ void __iomem *gpio_io;
+
+#ifdef CONFIG_PM
+ struct mlxbf2_gpio_context_save_regs *csave_regs;
+#endif
+};
+
+/* BlueField-2 gpio shared structure. */
+struct mlxbf2_gpio_param {
+ void __iomem *io;
+ struct resource *res;
+ struct mutex *lock;
+};
+
+static struct resource yu_arm_gpio_lock_res = {
+ .start = YU_ARM_GPIO_LOCK_ADDR,
+ .end = YU_ARM_GPIO_LOCK_ADDR + YU_ARM_GPIO_LOCK_SIZE - 1,
+ .name = "YU_ARM_GPIO_LOCK",
+};
+
+static DEFINE_MUTEX(yu_arm_gpio_lock_mutex);
+
+static struct mlxbf2_gpio_param yu_arm_gpio_lock_param = {
+ .res = &yu_arm_gpio_lock_res,
+ .lock = &yu_arm_gpio_lock_mutex,
+};
+
+/* Request memory region and map yu_arm_gpio_lock resource */
+static int mlxbf2_gpio_get_lock_res(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct resource *res;
+ resource_size_t size;
+ int ret = 0;
+
+ mutex_lock(yu_arm_gpio_lock_param.lock);
+
+ /* Check if the memory map already exists */
+ if (yu_arm_gpio_lock_param.io)
+ goto exit;
+
+ res = yu_arm_gpio_lock_param.res;
+ size = resource_size(res);
+
+ if (!devm_request_mem_region(dev, res->start, size, res->name)) {
+ ret = -EFAULT;
+ goto exit;
+ }
+
+ yu_arm_gpio_lock_param.io = devm_ioremap(dev, res->start, size);
+ if (IS_ERR(yu_arm_gpio_lock_param.io))
+ ret = PTR_ERR(yu_arm_gpio_lock_param.io);
+
+exit:
+ mutex_unlock(yu_arm_gpio_lock_param.lock);
+
+ return ret;
+}
+
+/*
+ * Acquire the YU arm_gpio_lock to be able to change the direction
+ * mode. If the lock_active bit is already set, return an error.
+ */
+static int mlxbf2_gpio_lock_acquire(struct mlxbf2_gpio_context *gs)
+{
+ u32 arm_gpio_lock_val;
+
+ spin_lock(&gs->gc.bgpio_lock);
+ mutex_lock(yu_arm_gpio_lock_param.lock);
+
+ arm_gpio_lock_val = readl(yu_arm_gpio_lock_param.io);
+
+ /*
+ * When lock active bit[31] is set, ModeX is write enabled
+ */
+ if (YU_LOCK_ACTIVE_BIT(arm_gpio_lock_val)) {
+ mutex_unlock(yu_arm_gpio_lock_param.lock);
+ spin_unlock(&gs->gc.bgpio_lock);
+ return -EINVAL;
+ }
+
+ writel(YU_ARM_GPIO_LOCK_ACQUIRE, yu_arm_gpio_lock_param.io);
+
+ return 0;
+}
+
+/*
+ * Release the YU arm_gpio_lock after changing the direction mode.
+ */
+static void mlxbf2_gpio_lock_release(struct mlxbf2_gpio_context *gs)
+{
+ writel(YU_ARM_GPIO_LOCK_RELEASE, yu_arm_gpio_lock_param.io);
+ mutex_unlock(yu_arm_gpio_lock_param.lock);
+ spin_unlock(&gs->gc.bgpio_lock);
+}
+
+/*
+ * mode0 and mode1 are both locked by the gpio_lock field.
+ *
+ * Together, mode0 and mode1 define the gpio Mode dependeing also
+ * on Reg_DataOut.
+ *
+ * {mode1,mode0}:{Reg_DataOut=0,Reg_DataOut=1}->{DataOut=0,DataOut=1}
+ *
+ * {0,0}:Reg_DataOut{0,1}->{Z,Z} Input PAD
+ * {0,1}:Reg_DataOut{0,1}->{0,1} Full drive Output PAD
+ * {1,0}:Reg_DataOut{0,1}->{0,Z} 0-set PAD to low, 1-float
+ * {1,1}:Reg_DataOut{0,1}->{Z,1} 0-float, 1-set PAD to high
+ */
+
+/*
+ * Set input direction:
+ * {mode1,mode0} = {0,0}
+ */
+static int mlxbf2_gpio_direction_input(struct gpio_chip *chip,
+ unsigned int offset)
+{
+ struct mlxbf2_gpio_context *gs = gpiochip_get_data(chip);
+ int ret;
+
+ /*
+ * Although the arm_gpio_lock was set in the probe function, check again
+ * if it is still enabled to be able to write to the ModeX registers.
+ */
+ ret = mlxbf2_gpio_lock_acquire(gs);
+ if (ret < 0)
+ return ret;
+
+ writel(BIT(offset), gs->gpio_io + YU_GPIO_MODE0_CLEAR);
+ writel(BIT(offset), gs->gpio_io + YU_GPIO_MODE1_CLEAR);
+
+ mlxbf2_gpio_lock_release(gs);
+
+ return ret;
+}
+
+/*
+ * Set output direction:
+ * {mode1,mode0} = {0,1}
+ */
+static int mlxbf2_gpio_direction_output(struct gpio_chip *chip,
+ unsigned int offset,
+ int value)
+{
+ struct mlxbf2_gpio_context *gs = gpiochip_get_data(chip);
+ int ret = 0;
+
+ /*
+ * Although the arm_gpio_lock was set in the probe function,
+ * check again it is still enabled to be able to write to the
+ * ModeX registers.
+ */
+ ret = mlxbf2_gpio_lock_acquire(gs);
+ if (ret < 0)
+ return ret;
+
+ writel(BIT(offset), gs->gpio_io + YU_GPIO_MODE1_CLEAR);
+ writel(BIT(offset), gs->gpio_io + YU_GPIO_MODE0_SET);
+
+ mlxbf2_gpio_lock_release(gs);
+
+ return ret;
+}
+
+/* BlueField-2 GPIO driver initialization routine. */
+static int
+mlxbf2_gpio_probe(struct platform_device *pdev)
+{
+ struct mlxbf2_gpio_context *gs;
+ struct device *dev = &pdev->dev;
+ struct gpio_chip *gc;
+ struct resource *res;
+ unsigned int npins;
+ int ret;
+
+ gs = devm_kzalloc(dev, sizeof(*gs), GFP_KERNEL);
+ if (!gs)
+ return -ENOMEM;
+
+ /* YU GPIO block address */
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+
+ gs->gpio_io = devm_ioremap(dev, res->start, resource_size(res));
+ if (!gs->gpio_io)
+ return -ENOMEM;
+
+ ret = mlxbf2_gpio_get_lock_res(pdev);
+ if (ret) {
+ dev_err(dev, "Failed to get yu_arm_gpio_lock resource\n");
+ return ret;
+ }
+
+ if (device_property_read_u32(dev, "npins", &npins))
+ npins = MLXBF2_GPIO_MAX_PINS_PER_BLOCK;
+
+ gc = &gs->gc;
+
+ ret = bgpio_init(gc, dev, 4,
+ gs->gpio_io + YU_GPIO_DATAIN,
+ gs->gpio_io + YU_GPIO_DATASET,
+ gs->gpio_io + YU_GPIO_DATACLEAR,
+ NULL,
+ NULL,
+ 0);
+
+ gc->direction_input = mlxbf2_gpio_direction_input;
+ gc->direction_output = mlxbf2_gpio_direction_output;
+ gc->ngpio = npins;
+ gc->owner = THIS_MODULE;
+
+ platform_set_drvdata(pdev, gs);
+
+ ret = devm_gpiochip_add_data(dev, &gs->gc, gs);
+ if (ret) {
+ dev_err(dev, "Failed adding memory mapped gpiochip\n");
+ return ret;
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int mlxbf2_gpio_suspend(struct platform_device *pdev,
+ pm_message_t state)
+{
+ struct mlxbf2_gpio_context *gs = platform_get_drvdata(pdev);
+
+ gs->csave_regs->gpio_mode0 = readl(gs->gpio_io +
+ YU_GPIO_MODE0);
+ gs->csave_regs->gpio_mode1 = readl(gs->gpio_io +
+ YU_GPIO_MODE1);
+
+ return 0;
+}
+
+static int mlxbf2_gpio_resume(struct platform_device *pdev)
+{
+ struct mlxbf2_gpio_context *gs = platform_get_drvdata(pdev);
+
+ writel(gs->csave_regs->gpio_mode0, gs->gpio_io +
+ YU_GPIO_MODE0);
+ writel(gs->csave_regs->gpio_mode1, gs->gpio_io +
+ YU_GPIO_MODE1);
+
+ return 0;
+}
+#endif
+
+static const struct acpi_device_id mlxbf2_gpio_acpi_match[] = {
+ { "MLNXBF22", 0 },
+ {},
+};
+MODULE_DEVICE_TABLE(acpi, mlxbf2_gpio_acpi_match);
+
+static struct platform_driver mlxbf2_gpio_driver = {
+ .driver = {
+ .name = "mlxbf2_gpio",
+ .acpi_match_table = ACPI_PTR(mlxbf2_gpio_acpi_match),
+ },
+ .probe = mlxbf2_gpio_probe,
+#ifdef CONFIG_PM
+ .suspend = mlxbf2_gpio_suspend,
+ .resume = mlxbf2_gpio_resume,
+#endif
+};
+
+module_platform_driver(mlxbf2_gpio_driver);
+
+MODULE_DESCRIPTION("Mellanox BlueField-2 GPIO Driver");
+MODULE_AUTHOR("Mellanox Technologies");
+MODULE_LICENSE("GPL v2");
diff --git a/drivers/gpio/gpio-mockup.c b/drivers/gpio/gpio-mockup.c
index 7d343bea784a..3eb94f3740d1 100644
--- a/drivers/gpio/gpio-mockup.c
+++ b/drivers/gpio/gpio-mockup.c
@@ -171,7 +171,7 @@ static int gpio_mockup_apply_pull(struct gpio_mockup_chip *chip,
/* Change the value unless we're actively driving the line. */
if (!test_bit(FLAG_REQUESTED, &desc->flags) ||
- !test_bit(FLAG_IS_OUT, &desc->flags))
+ !test_bit(FLAG_IS_OUT, &desc->flags))
__gpio_mockup_set(chip, offset, value);
out:
diff --git a/drivers/gpio/gpio-pxa.c b/drivers/gpio/gpio-pxa.c
index 9888b62f37af..567742d962ae 100644
--- a/drivers/gpio/gpio-pxa.c
+++ b/drivers/gpio/gpio-pxa.c
@@ -652,8 +652,8 @@ static int pxa_gpio_probe(struct platform_device *pdev)
if (!pchip->irqdomain)
return -ENOMEM;
- irq0 = platform_get_irq_byname(pdev, "gpio0");
- irq1 = platform_get_irq_byname(pdev, "gpio1");
+ irq0 = platform_get_irq_byname_optional(pdev, "gpio0");
+ irq1 = platform_get_irq_byname_optional(pdev, "gpio1");
irq_mux = platform_get_irq_byname(pdev, "gpio_mux");
if ((irq0 > 0 && irq1 <= 0) || (irq0 <= 0 && irq1 > 0)
|| (irq_mux <= 0))
diff --git a/drivers/gpio/gpio-rcar.c b/drivers/gpio/gpio-rcar.c
index f800b250971c..7284473c9fe3 100644
--- a/drivers/gpio/gpio-rcar.c
+++ b/drivers/gpio/gpio-rcar.c
@@ -116,7 +116,7 @@ static void gpio_rcar_config_interrupt_input_mode(struct gpio_rcar_priv *p,
spin_lock_irqsave(&p->lock, flags);
- /* Configure postive or negative logic in POSNEG */
+ /* Configure positive or negative logic in POSNEG */
gpio_rcar_modify_bit(p, POSNEG, hwirq, !active_high_rising_edge);
/* Configure edge or level trigger in EDGLEVEL */
@@ -228,7 +228,7 @@ static void gpio_rcar_config_general_input_output_mode(struct gpio_chip *chip,
spin_lock_irqsave(&p->lock, flags);
- /* Configure postive logic in POSNEG */
+ /* Configure positive logic in POSNEG */
gpio_rcar_modify_bit(p, POSNEG, gpio, false);
/* Select "General Input/Output Mode" in IOINTSEL */
diff --git a/drivers/gpio/gpio-siox.c b/drivers/gpio/gpio-siox.c
index 311f66757b92..26e1fe092304 100644
--- a/drivers/gpio/gpio-siox.c
+++ b/drivers/gpio/gpio-siox.c
@@ -15,7 +15,7 @@ struct gpio_siox_ddata {
u8 setdata[1];
u8 getdata[3];
- spinlock_t irqlock;
+ raw_spinlock_t irqlock;
u32 irq_enable;
u32 irq_status;
u32 irq_type[20];
@@ -44,7 +44,7 @@ static int gpio_siox_get_data(struct siox_device *sdevice, const u8 buf[])
mutex_lock(&ddata->lock);
- spin_lock_irq(&ddata->irqlock);
+ raw_spin_lock_irq(&ddata->irqlock);
for (offset = 0; offset < 12; ++offset) {
unsigned int bitpos = 11 - offset;
@@ -66,7 +66,7 @@ static int gpio_siox_get_data(struct siox_device *sdevice, const u8 buf[])
trigger = ddata->irq_status & ddata->irq_enable;
- spin_unlock_irq(&ddata->irqlock);
+ raw_spin_unlock_irq(&ddata->irqlock);
ddata->getdata[0] = buf[0];
ddata->getdata[1] = buf[1];
@@ -84,9 +84,9 @@ static int gpio_siox_get_data(struct siox_device *sdevice, const u8 buf[])
* handler of the irq chip. But it doesn't, so we have
* to clean the irq_status here.
*/
- spin_lock_irq(&ddata->irqlock);
+ raw_spin_lock_irq(&ddata->irqlock);
ddata->irq_status &= ~(1 << offset);
- spin_unlock_irq(&ddata->irqlock);
+ raw_spin_unlock_irq(&ddata->irqlock);
handle_nested_irq(irq);
}
@@ -101,9 +101,9 @@ static void gpio_siox_irq_ack(struct irq_data *d)
struct gpio_siox_ddata *ddata =
container_of(ic, struct gpio_siox_ddata, ichip);
- spin_lock_irq(&ddata->irqlock);
+ raw_spin_lock(&ddata->irqlock);
ddata->irq_status &= ~(1 << d->hwirq);
- spin_unlock_irq(&ddata->irqlock);
+ raw_spin_unlock(&ddata->irqlock);
}
static void gpio_siox_irq_mask(struct irq_data *d)
@@ -112,9 +112,9 @@ static void gpio_siox_irq_mask(struct irq_data *d)
struct gpio_siox_ddata *ddata =
container_of(ic, struct gpio_siox_ddata, ichip);
- spin_lock_irq(&ddata->irqlock);
+ raw_spin_lock(&ddata->irqlock);
ddata->irq_enable &= ~(1 << d->hwirq);
- spin_unlock_irq(&ddata->irqlock);
+ raw_spin_unlock(&ddata->irqlock);
}
static void gpio_siox_irq_unmask(struct irq_data *d)
@@ -123,9 +123,9 @@ static void gpio_siox_irq_unmask(struct irq_data *d)
struct gpio_siox_ddata *ddata =
container_of(ic, struct gpio_siox_ddata, ichip);
- spin_lock_irq(&ddata->irqlock);
+ raw_spin_lock(&ddata->irqlock);
ddata->irq_enable |= 1 << d->hwirq;
- spin_unlock_irq(&ddata->irqlock);
+ raw_spin_unlock(&ddata->irqlock);
}
static int gpio_siox_irq_set_type(struct irq_data *d, u32 type)
@@ -134,9 +134,9 @@ static int gpio_siox_irq_set_type(struct irq_data *d, u32 type)
struct gpio_siox_ddata *ddata =
container_of(ic, struct gpio_siox_ddata, ichip);
- spin_lock_irq(&ddata->irqlock);
+ raw_spin_lock(&ddata->irqlock);
ddata->irq_type[d->hwirq] = type;
- spin_unlock_irq(&ddata->irqlock);
+ raw_spin_unlock(&ddata->irqlock);
return 0;
}
@@ -222,7 +222,7 @@ static int gpio_siox_probe(struct siox_device *sdevice)
dev_set_drvdata(dev, ddata);
mutex_init(&ddata->lock);
- spin_lock_init(&ddata->irqlock);
+ raw_spin_lock_init(&ddata->irqlock);
ddata->gchip.base = -1;
ddata->gchip.can_sleep = 1;
diff --git a/drivers/gpio/gpio-uniphier.c b/drivers/gpio/gpio-uniphier.c
index 7ec97499b7f7..f99f3c10bed0 100644
--- a/drivers/gpio/gpio-uniphier.c
+++ b/drivers/gpio/gpio-uniphier.c
@@ -30,7 +30,7 @@ struct uniphier_gpio_priv {
struct irq_domain *domain;
void __iomem *regs;
spinlock_t lock;
- u32 saved_vals[0];
+ u32 saved_vals[];
};
static unsigned int uniphier_gpio_bank_to_reg(unsigned int bank)
diff --git a/drivers/gpio/gpio-wcd934x.c b/drivers/gpio/gpio-wcd934x.c
index 74913f2e5697..1cbce5990855 100644
--- a/drivers/gpio/gpio-wcd934x.c
+++ b/drivers/gpio/gpio-wcd934x.c
@@ -57,16 +57,19 @@ static int wcd_gpio_direction_output(struct gpio_chip *chip, unsigned int pin,
static int wcd_gpio_get(struct gpio_chip *chip, unsigned int pin)
{
struct wcd_gpio_data *data = gpiochip_get_data(chip);
- int value;
+ unsigned int value;
regmap_read(data->map, WCD_REG_VAL_CTL_OFFSET, &value);
- return !!(value && WCD_PIN_MASK(pin));
+ return !!(value & WCD_PIN_MASK(pin));
}
static void wcd_gpio_set(struct gpio_chip *chip, unsigned int pin, int val)
{
- wcd_gpio_direction_output(chip, pin, val);
+ struct wcd_gpio_data *data = gpiochip_get_data(chip);
+
+ regmap_update_bits(data->map, WCD_REG_VAL_CTL_OFFSET,
+ WCD_PIN_MASK(pin), val ? WCD_PIN_MASK(pin) : 0);
}
static int wcd_gpio_probe(struct platform_device *pdev)
diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c
index c6d30f73df07..ccc449df3792 100644
--- a/drivers/gpio/gpiolib-of.c
+++ b/drivers/gpio/gpiolib-of.c
@@ -605,6 +605,39 @@ static struct gpio_desc *of_parse_own_gpio(struct device_node *np,
}
/**
+ * of_gpiochip_add_hog - Add all hogs in a hog device node
+ * @chip: gpio chip to act on
+ * @hog: device node describing the hogs
+ *
+ * Returns error if it fails otherwise 0 on success.
+ */
+static int of_gpiochip_add_hog(struct gpio_chip *chip, struct device_node *hog)
+{
+ enum gpiod_flags dflags;
+ struct gpio_desc *desc;
+ unsigned long lflags;
+ const char *name;
+ unsigned int i;
+ int ret;
+
+ for (i = 0;; i++) {
+ desc = of_parse_own_gpio(hog, chip, i, &name, &lflags, &dflags);
+ if (IS_ERR(desc))
+ break;
+
+ ret = gpiod_hog(desc, name, lflags, dflags);
+ if (ret < 0)
+ return ret;
+
+#ifdef CONFIG_OF_DYNAMIC
+ desc->hog = hog;
+#endif
+ }
+
+ return 0;
+}
+
+/**
* of_gpiochip_scan_gpios - Scan gpio-controller for gpio definitions
* @chip: gpio chip to act on
*
@@ -614,35 +647,109 @@ static struct gpio_desc *of_parse_own_gpio(struct device_node *np,
*/
static int of_gpiochip_scan_gpios(struct gpio_chip *chip)
{
- struct gpio_desc *desc = NULL;
struct device_node *np;
- const char *name;
- unsigned long lflags;
- enum gpiod_flags dflags;
- unsigned int i;
int ret;
for_each_available_child_of_node(chip->of_node, np) {
if (!of_property_read_bool(np, "gpio-hog"))
continue;
- for (i = 0;; i++) {
- desc = of_parse_own_gpio(np, chip, i, &name, &lflags,
- &dflags);
- if (IS_ERR(desc))
- break;
-
- ret = gpiod_hog(desc, name, lflags, dflags);
- if (ret < 0) {
- of_node_put(np);
- return ret;
- }
+ ret = of_gpiochip_add_hog(chip, np);
+ if (ret < 0) {
+ of_node_put(np);
+ return ret;
}
+
+ of_node_set_flag(np, OF_POPULATED);
}
return 0;
}
+#ifdef CONFIG_OF_DYNAMIC
+/**
+ * of_gpiochip_remove_hog - Remove all hogs in a hog device node
+ * @chip: gpio chip to act on
+ * @hog: device node describing the hogs
+ */
+static void of_gpiochip_remove_hog(struct gpio_chip *chip,
+ struct device_node *hog)
+{
+ struct gpio_desc *descs = chip->gpiodev->descs;
+ unsigned int i;
+
+ for (i = 0; i < chip->ngpio; i++) {
+ if (test_bit(FLAG_IS_HOGGED, &descs[i].flags) &&
+ descs[i].hog == hog)
+ gpiochip_free_own_desc(&descs[i]);
+ }
+}
+
+static int of_gpiochip_match_node(struct gpio_chip *chip, void *data)
+{
+ return chip->gpiodev->dev.of_node == data;
+}
+
+static struct gpio_chip *of_find_gpiochip_by_node(struct device_node *np)
+{
+ return gpiochip_find(np, of_gpiochip_match_node);
+}
+
+static int of_gpio_notify(struct notifier_block *nb, unsigned long action,
+ void *arg)
+{
+ struct of_reconfig_data *rd = arg;
+ struct gpio_chip *chip;
+ int ret;
+
+ /*
+ * This only supports adding and removing complete gpio-hog nodes.
+ * Modifying an existing gpio-hog node is not supported (except for
+ * changing its "status" property, which is treated the same as
+ * addition/removal).
+ */
+ switch (of_reconfig_get_state_change(action, arg)) {
+ case OF_RECONFIG_CHANGE_ADD:
+ if (!of_property_read_bool(rd->dn, "gpio-hog"))
+ return NOTIFY_OK; /* not for us */
+
+ if (of_node_test_and_set_flag(rd->dn, OF_POPULATED))
+ return NOTIFY_OK;
+
+ chip = of_find_gpiochip_by_node(rd->dn->parent);
+ if (chip == NULL)
+ return NOTIFY_OK; /* not for us */
+
+ ret = of_gpiochip_add_hog(chip, rd->dn);
+ if (ret < 0) {
+ pr_err("%s: failed to add hogs for %pOF\n", __func__,
+ rd->dn);
+ of_node_clear_flag(rd->dn, OF_POPULATED);
+ return notifier_from_errno(ret);
+ }
+ break;
+
+ case OF_RECONFIG_CHANGE_REMOVE:
+ if (!of_node_check_flag(rd->dn, OF_POPULATED))
+ return NOTIFY_OK; /* already depopulated */
+
+ chip = of_find_gpiochip_by_node(rd->dn->parent);
+ if (chip == NULL)
+ return NOTIFY_OK; /* not for us */
+
+ of_gpiochip_remove_hog(chip, rd->dn);
+ of_node_clear_flag(rd->dn, OF_POPULATED);
+ break;
+ }
+
+ return NOTIFY_OK;
+}
+
+struct notifier_block gpio_of_notifier = {
+ .notifier_call = of_gpio_notify,
+};
+#endif /* CONFIG_OF_DYNAMIC */
+
/**
* of_gpio_simple_xlate - translate gpiospec to the GPIO number and flags
* @gc: pointer to the gpio_chip structure
diff --git a/drivers/gpio/gpiolib-of.h b/drivers/gpio/gpiolib-of.h
index 9768831b1fe2..ed26664f1537 100644
--- a/drivers/gpio/gpiolib-of.h
+++ b/drivers/gpio/gpiolib-of.h
@@ -35,4 +35,6 @@ static inline bool of_gpio_need_valid_mask(const struct gpio_chip *gc)
}
#endif /* CONFIG_OF_GPIO */
+extern struct notifier_block gpio_of_notifier;
+
#endif /* GPIOLIB_OF_H */
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 753283486037..02f8b2b81199 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -546,6 +546,9 @@ static long linehandle_set_config(struct linehandle_state *lh,
if (ret)
return ret;
}
+
+ atomic_notifier_call_chain(&desc->gdev->notifier,
+ GPIOLINE_CHANGED_CONFIG, desc);
}
return 0;
}
@@ -787,8 +790,6 @@ out_free_lh:
* @irq: the interrupt that trigger in response to events on this GPIO
* @wait: wait queue that handles blocking reads of events
* @events: KFIFO for the GPIO events
- * @read_lock: mutex lock to protect reads from colliding with adding
- * new events to the FIFO
* @timestamp: cache for the timestamp storing it between hardirq
* and IRQ thread, used to bring the timestamp close to the actual
* event
@@ -801,7 +802,6 @@ struct lineevent_state {
int irq;
wait_queue_head_t wait;
DECLARE_KFIFO(events, struct gpioevent_data, 16);
- struct mutex read_lock;
u64 timestamp;
};
@@ -817,7 +817,7 @@ static __poll_t lineevent_poll(struct file *filep,
poll_wait(filep, &le->wait, wait);
- if (!kfifo_is_empty(&le->events))
+ if (!kfifo_is_empty_spinlocked_noirqsave(&le->events, &le->wait.lock))
events = EPOLLIN | EPOLLRDNORM;
return events;
@@ -830,43 +830,52 @@ static ssize_t lineevent_read(struct file *filep,
loff_t *f_ps)
{
struct lineevent_state *le = filep->private_data;
- unsigned int copied;
+ struct gpioevent_data ge;
+ ssize_t bytes_read = 0;
int ret;
- if (count < sizeof(struct gpioevent_data))
+ if (count < sizeof(ge))
return -EINVAL;
do {
+ spin_lock(&le->wait.lock);
if (kfifo_is_empty(&le->events)) {
- if (filep->f_flags & O_NONBLOCK)
+ if (bytes_read) {
+ spin_unlock(&le->wait.lock);
+ return bytes_read;
+ }
+
+ if (filep->f_flags & O_NONBLOCK) {
+ spin_unlock(&le->wait.lock);
return -EAGAIN;
+ }
- ret = wait_event_interruptible(le->wait,
+ ret = wait_event_interruptible_locked(le->wait,
!kfifo_is_empty(&le->events));
- if (ret)
+ if (ret) {
+ spin_unlock(&le->wait.lock);
return ret;
+ }
}
- if (mutex_lock_interruptible(&le->read_lock))
- return -ERESTARTSYS;
- ret = kfifo_to_user(&le->events, buf, count, &copied);
- mutex_unlock(&le->read_lock);
-
- if (ret)
- return ret;
-
- /*
- * If we couldn't read anything from the fifo (a different
- * thread might have been faster) we either return -EAGAIN if
- * the file descriptor is non-blocking, otherwise we go back to
- * sleep and wait for more data to arrive.
- */
- if (copied == 0 && (filep->f_flags & O_NONBLOCK))
- return -EAGAIN;
+ ret = kfifo_out(&le->events, &ge, 1);
+ spin_unlock(&le->wait.lock);
+ if (ret != 1) {
+ /*
+ * This should never happen - we were holding the lock
+ * from the moment we learned the fifo is no longer
+ * empty until now.
+ */
+ ret = -EIO;
+ break;
+ }
- } while (copied == 0);
+ if (copy_to_user(buf + bytes_read, &ge, sizeof(ge)))
+ return -EFAULT;
+ bytes_read += sizeof(ge);
+ } while (count >= bytes_read + sizeof(ge));
- return copied;
+ return bytes_read;
}
static int lineevent_release(struct inode *inode, struct file *filep)
@@ -945,7 +954,7 @@ static irqreturn_t lineevent_irq_thread(int irq, void *p)
* we didn't get the timestamp from lineevent_irq_handler().
*/
if (!le->timestamp)
- ge.timestamp = ktime_get_real_ns();
+ ge.timestamp = ktime_get_ns();
else
ge.timestamp = le->timestamp;
@@ -968,9 +977,12 @@ static irqreturn_t lineevent_irq_thread(int irq, void *p)
return IRQ_NONE;
}
- ret = kfifo_put(&le->events, ge);
+ ret = kfifo_in_spinlocked_noirqsave(&le->events, &ge,
+ 1, &le->wait.lock);
if (ret)
wake_up_poll(&le->wait, EPOLLIN);
+ else
+ pr_debug_ratelimited("event FIFO is full - event dropped\n");
return IRQ_HANDLED;
}
@@ -983,7 +995,7 @@ static irqreturn_t lineevent_irq_handler(int irq, void *p)
* Just store the timestamp in hardirq context so we get it as
* close in time as possible to the actual event.
*/
- le->timestamp = ktime_get_real_ns();
+ le->timestamp = ktime_get_ns();
return IRQ_WAKE_THREAD;
}
@@ -1083,7 +1095,6 @@ static int lineevent_create(struct gpio_device *gdev, void __user *ip)
INIT_KFIFO(le->events);
init_waitqueue_head(&le->wait);
- mutex_init(&le->read_lock);
/* Request a thread to read the events */
ret = request_threaded_irq(le->irq,
@@ -1139,14 +1150,79 @@ out_free_le:
return ret;
}
+static void gpio_desc_to_lineinfo(struct gpio_desc *desc,
+ struct gpioline_info *info)
+{
+ struct gpio_chip *chip = desc->gdev->chip;
+ unsigned long flags;
+
+ spin_lock_irqsave(&gpio_lock, flags);
+
+ if (desc->name) {
+ strncpy(info->name, desc->name, sizeof(info->name));
+ info->name[sizeof(info->name) - 1] = '\0';
+ } else {
+ info->name[0] = '\0';
+ }
+
+ if (desc->label) {
+ strncpy(info->consumer, desc->label, sizeof(info->consumer));
+ info->consumer[sizeof(info->consumer) - 1] = '\0';
+ } else {
+ info->consumer[0] = '\0';
+ }
+
+ /*
+ * Userspace only need to know that the kernel is using this GPIO so
+ * it can't use it.
+ */
+ info->flags = 0;
+ if (test_bit(FLAG_REQUESTED, &desc->flags) ||
+ test_bit(FLAG_IS_HOGGED, &desc->flags) ||
+ test_bit(FLAG_USED_AS_IRQ, &desc->flags) ||
+ test_bit(FLAG_EXPORT, &desc->flags) ||
+ test_bit(FLAG_SYSFS, &desc->flags) ||
+ !pinctrl_gpio_can_use_line(chip->base + info->line_offset))
+ info->flags |= GPIOLINE_FLAG_KERNEL;
+ if (test_bit(FLAG_IS_OUT, &desc->flags))
+ info->flags |= GPIOLINE_FLAG_IS_OUT;
+ if (test_bit(FLAG_ACTIVE_LOW, &desc->flags))
+ info->flags |= GPIOLINE_FLAG_ACTIVE_LOW;
+ if (test_bit(FLAG_OPEN_DRAIN, &desc->flags))
+ info->flags |= (GPIOLINE_FLAG_OPEN_DRAIN |
+ GPIOLINE_FLAG_IS_OUT);
+ if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
+ info->flags |= (GPIOLINE_FLAG_OPEN_SOURCE |
+ GPIOLINE_FLAG_IS_OUT);
+ if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
+ info->flags |= GPIOLINE_FLAG_BIAS_DISABLE;
+ if (test_bit(FLAG_PULL_DOWN, &desc->flags))
+ info->flags |= GPIOLINE_FLAG_BIAS_PULL_DOWN;
+ if (test_bit(FLAG_PULL_UP, &desc->flags))
+ info->flags |= GPIOLINE_FLAG_BIAS_PULL_UP;
+
+ spin_unlock_irqrestore(&gpio_lock, flags);
+}
+
+struct gpio_chardev_data {
+ struct gpio_device *gdev;
+ wait_queue_head_t wait;
+ DECLARE_KFIFO(events, struct gpioline_info_changed, 32);
+ struct notifier_block lineinfo_changed_nb;
+ unsigned long *watched_lines;
+};
+
/*
* gpio_ioctl() - ioctl handler for the GPIO chardev
*/
static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
- struct gpio_device *gdev = filp->private_data;
+ struct gpio_chardev_data *priv = filp->private_data;
+ struct gpio_device *gdev = priv->gdev;
struct gpio_chip *chip = gdev->chip;
void __user *ip = (void __user *)arg;
+ struct gpio_desc *desc;
+ __u32 offset;
/* We fail any subsequent ioctl():s when the chip is gone */
if (!chip)
@@ -1168,9 +1244,9 @@ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
if (copy_to_user(ip, &chipinfo, sizeof(chipinfo)))
return -EFAULT;
return 0;
- } else if (cmd == GPIO_GET_LINEINFO_IOCTL) {
+ } else if (cmd == GPIO_GET_LINEINFO_IOCTL ||
+ cmd == GPIO_GET_LINEINFO_WATCH_IOCTL) {
struct gpioline_info lineinfo;
- struct gpio_desc *desc;
if (copy_from_user(&lineinfo, ip, sizeof(lineinfo)))
return -EFAULT;
@@ -1179,57 +1255,29 @@ static long gpio_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
if (IS_ERR(desc))
return PTR_ERR(desc);
- if (desc->name) {
- strncpy(lineinfo.name, desc->name,
- sizeof(lineinfo.name));
- lineinfo.name[sizeof(lineinfo.name)-1] = '\0';
- } else {
- lineinfo.name[0] = '\0';
- }
- if (desc->label) {
- strncpy(lineinfo.consumer, desc->label,
- sizeof(lineinfo.consumer));
- lineinfo.consumer[sizeof(lineinfo.consumer)-1] = '\0';
- } else {
- lineinfo.consumer[0] = '\0';
- }
-
- /*
- * Userspace only need to know that the kernel is using
- * this GPIO so it can't use it.
- */
- lineinfo.flags = 0;
- if (test_bit(FLAG_REQUESTED, &desc->flags) ||
- test_bit(FLAG_IS_HOGGED, &desc->flags) ||
- test_bit(FLAG_USED_AS_IRQ, &desc->flags) ||
- test_bit(FLAG_EXPORT, &desc->flags) ||
- test_bit(FLAG_SYSFS, &desc->flags) ||
- !pinctrl_gpio_can_use_line(chip->base + lineinfo.line_offset))
- lineinfo.flags |= GPIOLINE_FLAG_KERNEL;
- if (test_bit(FLAG_IS_OUT, &desc->flags))
- lineinfo.flags |= GPIOLINE_FLAG_IS_OUT;
- 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 |
- GPIOLINE_FLAG_IS_OUT);
- if (test_bit(FLAG_OPEN_SOURCE, &desc->flags))
- lineinfo.flags |= (GPIOLINE_FLAG_OPEN_SOURCE |
- GPIOLINE_FLAG_IS_OUT);
- if (test_bit(FLAG_BIAS_DISABLE, &desc->flags))
- lineinfo.flags |= GPIOLINE_FLAG_BIAS_DISABLE;
- if (test_bit(FLAG_PULL_DOWN, &desc->flags))
- lineinfo.flags |= GPIOLINE_FLAG_BIAS_PULL_DOWN;
- if (test_bit(FLAG_PULL_UP, &desc->flags))
- lineinfo.flags |= GPIOLINE_FLAG_BIAS_PULL_UP;
+ gpio_desc_to_lineinfo(desc, &lineinfo);
if (copy_to_user(ip, &lineinfo, sizeof(lineinfo)))
return -EFAULT;
+
+ if (cmd == GPIO_GET_LINEINFO_WATCH_IOCTL)
+ set_bit(gpio_chip_hwgpio(desc), priv->watched_lines);
+
return 0;
} else if (cmd == GPIO_GET_LINEHANDLE_IOCTL) {
return linehandle_create(gdev, ip);
} else if (cmd == GPIO_GET_LINEEVENT_IOCTL) {
return lineevent_create(gdev, ip);
+ } else if (cmd == GPIO_GET_LINEINFO_UNWATCH_IOCTL) {
+ if (copy_from_user(&offset, ip, sizeof(offset)))
+ return -EFAULT;
+
+ desc = gpiochip_get_desc(chip, offset);
+ if (IS_ERR(desc))
+ return PTR_ERR(desc);
+
+ clear_bit(gpio_chip_hwgpio(desc), priv->watched_lines);
+ return 0;
}
return -EINVAL;
}
@@ -1242,6 +1290,101 @@ static long gpio_ioctl_compat(struct file *filp, unsigned int cmd,
}
#endif
+static struct gpio_chardev_data *
+to_gpio_chardev_data(struct notifier_block *nb)
+{
+ return container_of(nb, struct gpio_chardev_data, lineinfo_changed_nb);
+}
+
+static int lineinfo_changed_notify(struct notifier_block *nb,
+ unsigned long action, void *data)
+{
+ struct gpio_chardev_data *priv = to_gpio_chardev_data(nb);
+ struct gpioline_info_changed chg;
+ struct gpio_desc *desc = data;
+ int ret;
+
+ if (!test_bit(gpio_chip_hwgpio(desc), priv->watched_lines))
+ return NOTIFY_DONE;
+
+ memset(&chg, 0, sizeof(chg));
+ chg.info.line_offset = gpio_chip_hwgpio(desc);
+ chg.event_type = action;
+ chg.timestamp = ktime_get_ns();
+ gpio_desc_to_lineinfo(desc, &chg.info);
+
+ ret = kfifo_in_spinlocked(&priv->events, &chg, 1, &priv->wait.lock);
+ if (ret)
+ wake_up_poll(&priv->wait, EPOLLIN);
+ else
+ pr_debug_ratelimited("lineinfo event FIFO is full - event dropped\n");
+
+ return NOTIFY_OK;
+}
+
+static __poll_t lineinfo_watch_poll(struct file *filep,
+ struct poll_table_struct *pollt)
+{
+ struct gpio_chardev_data *priv = filep->private_data;
+ __poll_t events = 0;
+
+ poll_wait(filep, &priv->wait, pollt);
+
+ if (!kfifo_is_empty_spinlocked_noirqsave(&priv->events,
+ &priv->wait.lock))
+ events = EPOLLIN | EPOLLRDNORM;
+
+ return events;
+}
+
+static ssize_t lineinfo_watch_read(struct file *filep, char __user *buf,
+ size_t count, loff_t *off)
+{
+ struct gpio_chardev_data *priv = filep->private_data;
+ struct gpioline_info_changed event;
+ ssize_t bytes_read = 0;
+ int ret;
+
+ if (count < sizeof(event))
+ return -EINVAL;
+
+ do {
+ spin_lock(&priv->wait.lock);
+ if (kfifo_is_empty(&priv->events)) {
+ if (bytes_read) {
+ spin_unlock(&priv->wait.lock);
+ return bytes_read;
+ }
+
+ if (filep->f_flags & O_NONBLOCK) {
+ spin_unlock(&priv->wait.lock);
+ return -EAGAIN;
+ }
+
+ ret = wait_event_interruptible_locked(priv->wait,
+ !kfifo_is_empty(&priv->events));
+ if (ret) {
+ spin_unlock(&priv->wait.lock);
+ return ret;
+ }
+ }
+
+ ret = kfifo_out(&priv->events, &event, 1);
+ spin_unlock(&priv->wait.lock);
+ if (ret != 1) {
+ ret = -EIO;
+ break;
+ /* We should never get here. See lineevent_read(). */
+ }
+
+ if (copy_to_user(buf + bytes_read, &event, sizeof(event)))
+ return -EFAULT;
+ bytes_read += sizeof(event);
+ } while (count >= bytes_read + sizeof(event));
+
+ return bytes_read;
+}
+
/**
* gpio_chrdev_open() - open the chardev for ioctl operations
* @inode: inode for this chardev
@@ -1252,14 +1395,48 @@ static int gpio_chrdev_open(struct inode *inode, struct file *filp)
{
struct gpio_device *gdev = container_of(inode->i_cdev,
struct gpio_device, chrdev);
+ struct gpio_chardev_data *priv;
+ int ret = -ENOMEM;
/* Fail on open if the backing gpiochip is gone */
if (!gdev->chip)
return -ENODEV;
+
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->watched_lines = bitmap_zalloc(gdev->chip->ngpio, GFP_KERNEL);
+ if (!priv->watched_lines)
+ goto out_free_priv;
+
+ init_waitqueue_head(&priv->wait);
+ INIT_KFIFO(priv->events);
+ priv->gdev = gdev;
+
+ priv->lineinfo_changed_nb.notifier_call = lineinfo_changed_notify;
+ ret = atomic_notifier_chain_register(&gdev->notifier,
+ &priv->lineinfo_changed_nb);
+ if (ret)
+ goto out_free_bitmap;
+
get_device(&gdev->dev);
- filp->private_data = gdev;
+ filp->private_data = priv;
+
+ ret = nonseekable_open(inode, filp);
+ if (ret)
+ goto out_unregister_notifier;
- return nonseekable_open(inode, filp);
+ return ret;
+
+out_unregister_notifier:
+ atomic_notifier_chain_unregister(&gdev->notifier,
+ &priv->lineinfo_changed_nb);
+out_free_bitmap:
+ bitmap_free(priv->watched_lines);
+out_free_priv:
+ kfree(priv);
+ return ret;
}
/**
@@ -1270,17 +1447,23 @@ static int gpio_chrdev_open(struct inode *inode, struct file *filp)
*/
static int gpio_chrdev_release(struct inode *inode, struct file *filp)
{
- struct gpio_device *gdev = container_of(inode->i_cdev,
- struct gpio_device, chrdev);
+ struct gpio_chardev_data *priv = filp->private_data;
+ struct gpio_device *gdev = priv->gdev;
+ bitmap_free(priv->watched_lines);
+ atomic_notifier_chain_unregister(&gdev->notifier,
+ &priv->lineinfo_changed_nb);
put_device(&gdev->dev);
+ kfree(priv);
+
return 0;
}
-
static const struct file_operations gpio_fileops = {
.release = gpio_chrdev_release,
.open = gpio_chrdev_open,
+ .poll = lineinfo_watch_poll,
+ .read = lineinfo_watch_read,
.owner = THIS_MODULE,
.llseek = no_llseek,
.unlocked_ioctl = gpio_ioctl,
@@ -1491,6 +1674,8 @@ int gpiochip_add_data_with_key(struct gpio_chip *chip, void *data,
spin_unlock_irqrestore(&gpio_lock, flags);
+ ATOMIC_INIT_NOTIFIER_HEAD(&gdev->notifier);
+
#ifdef CONFIG_PINCTRL
INIT_LIST_HEAD(&gdev->pin_ranges);
#endif
@@ -1612,10 +1797,8 @@ EXPORT_SYMBOL_GPL(gpiochip_get_data);
void gpiochip_remove(struct gpio_chip *chip)
{
struct gpio_device *gdev = chip->gpiodev;
- struct gpio_desc *desc;
unsigned long flags;
- unsigned i;
- bool requested = false;
+ unsigned int i;
/* FIXME: should the legacy sysfs handling be moved to gpio_device? */
gpiochip_sysfs_unregister(gdev);
@@ -1635,13 +1818,12 @@ void gpiochip_remove(struct gpio_chip *chip)
spin_lock_irqsave(&gpio_lock, flags);
for (i = 0; i < gdev->ngpio; i++) {
- desc = &gdev->descs[i];
- if (test_bit(FLAG_REQUESTED, &desc->flags))
- requested = true;
+ if (gpiochip_is_requested(chip, i))
+ break;
}
spin_unlock_irqrestore(&gpio_lock, flags);
- if (requested)
+ if (i != gdev->ngpio)
dev_crit(&gdev->dev,
"REMOVING GPIOCHIP WITH GPIOS STILL REQUESTED\n");
@@ -2823,6 +3005,8 @@ static int gpiod_request_commit(struct gpio_desc *desc, const char *label)
}
done:
spin_unlock_irqrestore(&gpio_lock, flags);
+ atomic_notifier_call_chain(&desc->gdev->notifier,
+ GPIOLINE_CHANGED_REQUESTED, desc);
return ret;
}
@@ -2916,10 +3100,16 @@ static bool gpiod_free_commit(struct gpio_desc *desc)
clear_bit(FLAG_PULL_DOWN, &desc->flags);
clear_bit(FLAG_BIAS_DISABLE, &desc->flags);
clear_bit(FLAG_IS_HOGGED, &desc->flags);
+#ifdef CONFIG_OF_DYNAMIC
+ desc->hog = NULL;
+#endif
ret = true;
}
spin_unlock_irqrestore(&gpio_lock, flags);
+ atomic_notifier_call_chain(&desc->gdev->notifier,
+ GPIOLINE_CHANGED_RELEASED, desc);
+
return ret;
}
@@ -2953,7 +3143,9 @@ const char *gpiochip_is_requested(struct gpio_chip *chip, unsigned offset)
if (offset >= chip->ngpio)
return NULL;
- desc = &chip->gpiodev->descs[offset];
+ desc = gpiochip_get_desc(chip, offset);
+ if (IS_ERR(desc))
+ return NULL;
if (test_bit(FLAG_REQUESTED, &desc->flags) == 0)
return NULL;
@@ -5089,10 +5281,15 @@ static int __init gpiolib_dev_init(void)
if (ret < 0) {
pr_err("gpiolib: failed to allocate char dev region\n");
bus_unregister(&gpio_bus_type);
- } else {
- gpiolib_initialized = true;
- gpiochip_setup_devs();
+ return ret;
}
+
+ gpiolib_initialized = true;
+ gpiochip_setup_devs();
+
+ if (IS_ENABLED(CONFIG_OF_DYNAMIC))
+ WARN_ON(of_reconfig_notifier_register(&gpio_of_notifier));
+
return ret;
}
core_initcall(gpiolib_dev_init);
diff --git a/drivers/gpio/gpiolib.h b/drivers/gpio/gpiolib.h
index 3e0aab2945d8..853ce681b4a4 100644
--- a/drivers/gpio/gpiolib.h
+++ b/drivers/gpio/gpiolib.h
@@ -56,6 +56,7 @@ struct gpio_device {
const char *label;
void *data;
struct list_head list;
+ struct atomic_notifier_head notifier;
#ifdef CONFIG_PINCTRL
/*
@@ -119,6 +120,9 @@ struct gpio_desc {
const char *label;
/* Name of the GPIO */
const char *name;
+#ifdef CONFIG_OF_DYNAMIC
+ struct device_node *hog;
+#endif
};
int gpiod_request(struct gpio_desc *desc, const char *label);
diff --git a/include/asm-generic/gpio.h b/include/asm-generic/gpio.h
index 19eadac415c4..aea9aee1f3e9 100644
--- a/include/asm-generic/gpio.h
+++ b/include/asm-generic/gpio.h
@@ -2,10 +2,8 @@
#ifndef _ASM_GENERIC_GPIO_H
#define _ASM_GENERIC_GPIO_H
-#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/errno.h>
-#include <linux/of.h>
#ifdef CONFIG_GPIOLIB
@@ -140,6 +138,8 @@ static inline void gpio_unexport(unsigned gpio)
#else /* !CONFIG_GPIOLIB */
+#include <linux/kernel.h>
+
static inline bool gpio_is_valid(int number)
{
/* only non-negative numbers are valid */
diff --git a/include/linux/gpio.h b/include/linux/gpio.h
index 2157717c2136..008ad3ee56b7 100644
--- a/include/linux/gpio.h
+++ b/include/linux/gpio.h
@@ -102,11 +102,9 @@ void devm_gpio_free(struct device *dev, unsigned int gpio);
#include <linux/kernel.h>
#include <linux/types.h>
#include <linux/bug.h>
-#include <linux/pinctrl/pinctrl.h>
struct device;
struct gpio_chip;
-struct pinctrl_dev;
static inline bool gpio_is_valid(int number)
{
diff --git a/include/linux/gpio/consumer.h b/include/linux/gpio/consumer.h
index bf2d017dd7b7..0a72fccf60ff 100644
--- a/include/linux/gpio/consumer.h
+++ b/include/linux/gpio/consumer.h
@@ -2,9 +2,10 @@
#ifndef __LINUX_GPIO_CONSUMER_H
#define __LINUX_GPIO_CONSUMER_H
+#include <linux/bits.h>
#include <linux/bug.h>
+#include <linux/compiler_types.h>
#include <linux/err.h>
-#include <linux/kernel.h>
struct device;
@@ -189,6 +190,8 @@ struct gpio_desc *devm_fwnode_gpiod_get_index(struct device *dev,
#else /* CONFIG_GPIOLIB */
+#include <linux/kernel.h>
+
static inline int gpiod_count(struct device *dev, const char *con_id)
{
return 0;
diff --git a/include/linux/kfifo.h b/include/linux/kfifo.h
index fc4b0b10210f..86249476b57f 100644
--- a/include/linux/kfifo.h
+++ b/include/linux/kfifo.h
@@ -247,6 +247,37 @@ __kfifo_int_must_check_helper(int val)
})
/**
+ * kfifo_is_empty_spinlocked - returns true if the fifo is empty using
+ * a spinlock for locking
+ * @fifo: address of the fifo to be used
+ * @lock: spinlock to be used for locking
+ */
+#define kfifo_is_empty_spinlocked(fifo, lock) \
+({ \
+ unsigned long __flags; \
+ bool __ret; \
+ spin_lock_irqsave(lock, __flags); \
+ __ret = kfifo_is_empty(fifo); \
+ spin_unlock_irqrestore(lock, __flags); \
+ __ret; \
+})
+
+/**
+ * kfifo_is_empty_spinlocked_noirqsave - returns true if the fifo is empty
+ * using a spinlock for locking, doesn't disable interrupts
+ * @fifo: address of the fifo to be used
+ * @lock: spinlock to be used for locking
+ */
+#define kfifo_is_empty_spinlocked_noirqsave(fifo, lock) \
+({ \
+ bool __ret; \
+ spin_lock(lock); \
+ __ret = kfifo_is_empty(fifo); \
+ spin_unlock(lock); \
+ __ret; \
+})
+
+/**
* kfifo_is_full - returns true if the fifo is full
* @fifo: address of the fifo to be used
*/
@@ -517,6 +548,26 @@ __kfifo_uint_must_check_helper( \
__ret; \
})
+/**
+ * kfifo_in_spinlocked_noirqsave - put data into fifo using a spinlock for
+ * locking, don't disable interrupts
+ * @fifo: address of the fifo to be used
+ * @buf: the data to be added
+ * @n: number of elements to be added
+ * @lock: pointer to the spinlock to use for locking
+ *
+ * This is a variant of kfifo_in_spinlocked() but uses spin_lock/unlock()
+ * for locking and doesn't disable interrupts.
+ */
+#define kfifo_in_spinlocked_noirqsave(fifo, buf, n, lock) \
+({ \
+ unsigned int __ret; \
+ spin_lock(lock); \
+ __ret = kfifo_in(fifo, buf, n); \
+ spin_unlock(lock); \
+ __ret; \
+})
+
/* alias for kfifo_in_spinlocked, will be removed in a future release */
#define kfifo_in_locked(fifo, buf, n, lock) \
kfifo_in_spinlocked(fifo, buf, n, lock)
@@ -569,6 +620,28 @@ __kfifo_uint_must_check_helper( \
}) \
)
+/**
+ * kfifo_out_spinlocked_noirqsave - get data from the fifo using a spinlock
+ * for locking, don't disable interrupts
+ * @fifo: address of the fifo to be used
+ * @buf: pointer to the storage buffer
+ * @n: max. number of elements to get
+ * @lock: pointer to the spinlock to use for locking
+ *
+ * This is a variant of kfifo_out_spinlocked() which uses spin_lock/unlock()
+ * for locking and doesn't disable interrupts.
+ */
+#define kfifo_out_spinlocked_noirqsave(fifo, buf, n, lock) \
+__kfifo_uint_must_check_helper( \
+({ \
+ unsigned int __ret; \
+ spin_lock(lock); \
+ __ret = kfifo_out(fifo, buf, n); \
+ spin_unlock(lock); \
+ __ret; \
+}) \
+)
+
/* alias for kfifo_out_spinlocked, will be removed in a future release */
#define kfifo_out_locked(fifo, buf, n, lock) \
kfifo_out_spinlocked(fifo, buf, n, lock)
diff --git a/include/linux/of_gpio.h b/include/linux/of_gpio.h
index 16967390a3fe..f821095218b0 100644
--- a/include/linux/of_gpio.h
+++ b/include/linux/of_gpio.h
@@ -11,9 +11,8 @@
#define __LINUX_OF_GPIO_H
#include <linux/compiler.h>
-#include <linux/kernel.h>
-#include <linux/errno.h>
-#include <linux/gpio.h>
+#include <linux/gpio/driver.h>
+#include <linux/gpio.h> /* FIXME: Shouldn't be here */
#include <linux/of.h>
struct device_node;
@@ -34,6 +33,8 @@ enum of_gpio_flags {
#ifdef CONFIG_OF_GPIO
+#include <linux/kernel.h>
+
/*
* OF GPIO chip for memory mapped banks
*/
@@ -63,6 +64,8 @@ extern void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc);
#else /* CONFIG_OF_GPIO */
+#include <linux/errno.h>
+
/* Drivers may not strictly depend on the GPIO support, so let them link. */
static inline int of_get_named_gpio_flags(struct device_node *np,
const char *list_name, int index, enum of_gpio_flags *flags)
diff --git a/include/uapi/linux/gpio.h b/include/uapi/linux/gpio.h
index 799cf823d493..dca320764e4d 100644
--- a/include/uapi/linux/gpio.h
+++ b/include/uapi/linux/gpio.h
@@ -59,6 +59,34 @@ struct gpioline_info {
/* Maximum number of requested handles */
#define GPIOHANDLES_MAX 64
+/* Possible line status change events */
+enum {
+ GPIOLINE_CHANGED_REQUESTED = 1,
+ GPIOLINE_CHANGED_RELEASED,
+ GPIOLINE_CHANGED_CONFIG,
+};
+
+/**
+ * struct gpioline_info_changed - Information about a change in status
+ * of a GPIO line
+ * @info: updated line information
+ * @timestamp: estimate of time of status change occurrence, in nanoseconds
+ * and GPIOLINE_CHANGED_CONFIG
+ * @event_type: one of GPIOLINE_CHANGED_REQUESTED, GPIOLINE_CHANGED_RELEASED
+ *
+ * Note: struct gpioline_info embedded here has 32-bit alignment on its own,
+ * but it works fine with 64-bit alignment too. With its 72 byte size, we can
+ * guarantee there are no implicit holes between it and subsequent members.
+ * The 20-byte padding at the end makes sure we don't add any implicit padding
+ * at the end of the structure on 64-bit architectures.
+ */
+struct gpioline_info_changed {
+ struct gpioline_info info;
+ __u64 timestamp;
+ __u32 event_type;
+ __u32 padding[5]; /* for future use */
+};
+
/* Linerequest flags */
#define GPIOHANDLE_REQUEST_INPUT (1UL << 0)
#define GPIOHANDLE_REQUEST_OUTPUT (1UL << 1)
@@ -176,6 +204,8 @@ struct gpioevent_data {
#define GPIO_GET_CHIPINFO_IOCTL _IOR(0xB4, 0x01, struct gpiochip_info)
#define GPIO_GET_LINEINFO_IOCTL _IOWR(0xB4, 0x02, struct gpioline_info)
+#define GPIO_GET_LINEINFO_WATCH_IOCTL _IOWR(0xB4, 0x0b, struct gpioline_info)
+#define GPIO_GET_LINEINFO_UNWATCH_IOCTL _IOWR(0xB4, 0x0c, __u32)
#define GPIO_GET_LINEHANDLE_IOCTL _IOWR(0xB4, 0x03, struct gpiohandle_request)
#define GPIO_GET_LINEEVENT_IOCTL _IOWR(0xB4, 0x04, struct gpioevent_request)
diff --git a/tools/gpio/.gitignore b/tools/gpio/.gitignore
index a94c0e83b209..eab36c6d7751 100644
--- a/tools/gpio/.gitignore
+++ b/tools/gpio/.gitignore
@@ -1,4 +1,5 @@
gpio-event-mon
gpio-hammer
+gpio-watch
lsgpio
include/linux/gpio.h
diff --git a/tools/gpio/Build b/tools/gpio/Build
index 4141f35837db..67c7b7f6a717 100644
--- a/tools/gpio/Build
+++ b/tools/gpio/Build
@@ -2,3 +2,4 @@ gpio-utils-y += gpio-utils.o
lsgpio-y += lsgpio.o gpio-utils.o
gpio-hammer-y += gpio-hammer.o gpio-utils.o
gpio-event-mon-y += gpio-event-mon.o gpio-utils.o
+gpio-watch-y += gpio-watch.o
diff --git a/tools/gpio/Makefile b/tools/gpio/Makefile
index 6080de58861f..842287e42c83 100644
--- a/tools/gpio/Makefile
+++ b/tools/gpio/Makefile
@@ -18,7 +18,7 @@ MAKEFLAGS += -r
override CFLAGS += -O2 -Wall -g -D_GNU_SOURCE -I$(OUTPUT)include
-ALL_TARGETS := lsgpio gpio-hammer gpio-event-mon
+ALL_TARGETS := lsgpio gpio-hammer gpio-event-mon gpio-watch
ALL_PROGRAMS := $(patsubst %,$(OUTPUT)%,$(ALL_TARGETS))
all: $(ALL_PROGRAMS)
@@ -66,6 +66,15 @@ $(GPIO_EVENT_MON_IN): prepare FORCE $(OUTPUT)gpio-utils-in.o
$(OUTPUT)gpio-event-mon: $(GPIO_EVENT_MON_IN)
$(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $< -o $@
+#
+# gpio-watch
+#
+GPIO_WATCH_IN := $(OUTPUT)gpio-watch-in.o
+$(GPIO_WATCH_IN): prepare FORCE
+ $(Q)$(MAKE) $(build)=gpio-watch
+$(OUTPUT)gpio-watch: $(GPIO_WATCH_IN)
+ $(QUIET_LINK)$(CC) $(CFLAGS) $(LDFLAGS) $< -o $@
+
clean:
rm -f $(ALL_PROGRAMS)
rm -f $(OUTPUT)include/linux/gpio.h
diff --git a/tools/gpio/gpio-watch.c b/tools/gpio/gpio-watch.c
new file mode 100644
index 000000000000..5cea24fddfa7
--- /dev/null
+++ b/tools/gpio/gpio-watch.c
@@ -0,0 +1,99 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * gpio-watch - monitor unrequested lines for property changes using the
+ * character device
+ *
+ * Copyright (C) 2019 BayLibre SAS
+ * Author: Bartosz Golaszewski <bgolaszewski@baylibre.com>
+ */
+
+#include <ctype.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <linux/gpio.h>
+#include <poll.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/ioctl.h>
+#include <unistd.h>
+
+int main(int argc, char **argv)
+{
+ struct gpioline_info_changed chg;
+ struct gpioline_info req;
+ struct pollfd pfd;
+ int fd, i, j, ret;
+ char *event, *end;
+ ssize_t rd;
+
+ if (argc < 3)
+ goto err_usage;
+
+ fd = open(argv[1], O_RDWR | O_CLOEXEC);
+ if (fd < 0) {
+ perror("unable to open gpiochip");
+ return EXIT_FAILURE;
+ }
+
+ for (i = 0, j = 2; i < argc - 2; i++, j++) {
+ memset(&req, 0, sizeof(req));
+
+ req.line_offset = strtoul(argv[j], &end, 0);
+ if (*end != '\0')
+ goto err_usage;
+
+ ret = ioctl(fd, GPIO_GET_LINEINFO_WATCH_IOCTL, &req);
+ if (ret) {
+ perror("unable to set up line watch");
+ return EXIT_FAILURE;
+ }
+ }
+
+ pfd.fd = fd;
+ pfd.events = POLLIN | POLLPRI;
+
+ for (;;) {
+ ret = poll(&pfd, 1, 5000);
+ if (ret < 0) {
+ perror("error polling the linechanged fd");
+ return EXIT_FAILURE;
+ } else if (ret > 0) {
+ memset(&chg, 0, sizeof(chg));
+ rd = read(pfd.fd, &chg, sizeof(chg));
+ if (rd < 0 || rd != sizeof(chg)) {
+ if (rd != sizeof(chg))
+ errno = EIO;
+
+ perror("error reading line change event");
+ return EXIT_FAILURE;
+ }
+
+ switch (chg.event_type) {
+ case GPIOLINE_CHANGED_REQUESTED:
+ event = "requested";
+ break;
+ case GPIOLINE_CHANGED_RELEASED:
+ event = "released";
+ break;
+ case GPIOLINE_CHANGED_CONFIG:
+ event = "config changed";
+ break;
+ default:
+ fprintf(stderr,
+ "invalid event type received from the kernel\n");
+ return EXIT_FAILURE;
+ }
+
+ printf("line %u: %s at %llu\n",
+ chg.info.line_offset, event, chg.timestamp);
+ }
+ }
+
+ return 0;
+
+err_usage:
+ printf("%s: <gpiochip> <line0> <line1> ...\n", argv[0]);
+ return EXIT_FAILURE;
+}