diff --git a/drivers/gpio/gpio-mockup.c b/drivers/gpio/gpio-mockup.c index 6a50f9f59c90..154d959e8993 100644 --- a/drivers/gpio/gpio-mockup.c +++ b/drivers/gpio/gpio-mockup.c @@ -47,6 +47,7 @@ enum { struct gpio_mockup_line_status { int dir; int value; + int pull; }; struct gpio_mockup_chip { @@ -54,12 +55,13 @@ struct gpio_mockup_chip { struct gpio_mockup_line_status *lines; struct irq_sim irqsim; struct dentry *dbg_dir; + struct mutex lock; }; struct gpio_mockup_dbgfs_private { struct gpio_mockup_chip *chip; struct gpio_desc *desc; - int offset; + unsigned int offset; }; static int gpio_mockup_ranges[GPIO_MOCKUP_MAX_RANGES]; @@ -82,29 +84,66 @@ static int gpio_mockup_range_ngpio(unsigned int index) return gpio_mockup_ranges[index * 2 + 1]; } -static int gpio_mockup_get(struct gpio_chip *gc, unsigned int offset) +static int __gpio_mockup_get(struct gpio_mockup_chip *chip, + unsigned int offset) { - struct gpio_mockup_chip *chip = gpiochip_get_data(gc); - return chip->lines[offset].value; } +static int gpio_mockup_get(struct gpio_chip *gc, unsigned int offset) +{ + struct gpio_mockup_chip *chip = gpiochip_get_data(gc); + int val; + + mutex_lock(&chip->lock); + val = __gpio_mockup_get(chip, offset); + mutex_unlock(&chip->lock); + + return val; +} + +static int gpio_mockup_get_multiple(struct gpio_chip *gc, + unsigned long *mask, unsigned long *bits) +{ + struct gpio_mockup_chip *chip = gpiochip_get_data(gc); + unsigned int bit, val; + + mutex_lock(&chip->lock); + for_each_set_bit(bit, mask, gc->ngpio) { + val = __gpio_mockup_get(chip, bit); + __assign_bit(bit, bits, val); + } + mutex_unlock(&chip->lock); + + return 0; +} + +static void __gpio_mockup_set(struct gpio_mockup_chip *chip, + unsigned int offset, int value) +{ + chip->lines[offset].value = !!value; +} + static void gpio_mockup_set(struct gpio_chip *gc, - unsigned int offset, int value) + unsigned int offset, int value) { struct gpio_mockup_chip *chip = gpiochip_get_data(gc); - chip->lines[offset].value = !!value; + mutex_lock(&chip->lock); + __gpio_mockup_set(chip, offset, value); + mutex_unlock(&chip->lock); } static void gpio_mockup_set_multiple(struct gpio_chip *gc, unsigned long *mask, unsigned long *bits) { + struct gpio_mockup_chip *chip = gpiochip_get_data(gc); unsigned int bit; + mutex_lock(&chip->lock); for_each_set_bit(bit, mask, gc->ngpio) - gpio_mockup_set(gc, bit, test_bit(bit, bits)); - + __gpio_mockup_set(chip, bit, test_bit(bit, bits)); + mutex_unlock(&chip->lock); } static int gpio_mockup_dirout(struct gpio_chip *gc, @@ -112,8 +151,10 @@ static int gpio_mockup_dirout(struct gpio_chip *gc, { struct gpio_mockup_chip *chip = gpiochip_get_data(gc); - gpio_mockup_set(gc, offset, value); + mutex_lock(&chip->lock); chip->lines[offset].dir = GPIO_MOCKUP_DIR_OUT; + __gpio_mockup_set(chip, offset, value); + mutex_unlock(&chip->lock); return 0; } @@ -122,7 +163,9 @@ static int gpio_mockup_dirin(struct gpio_chip *gc, unsigned int offset) { struct gpio_mockup_chip *chip = gpiochip_get_data(gc); + mutex_lock(&chip->lock); chip->lines[offset].dir = GPIO_MOCKUP_DIR_IN; + mutex_unlock(&chip->lock); return 0; } @@ -130,8 +173,13 @@ static int gpio_mockup_dirin(struct gpio_chip *gc, unsigned int offset) static int gpio_mockup_get_direction(struct gpio_chip *gc, unsigned int offset) { struct gpio_mockup_chip *chip = gpiochip_get_data(gc); + int direction; - return !chip->lines[offset].dir; + mutex_lock(&chip->lock); + direction = !chip->lines[offset].dir; + mutex_unlock(&chip->lock); + + return direction; } static int gpio_mockup_to_irq(struct gpio_chip *gc, unsigned int offset) @@ -141,15 +189,56 @@ static int gpio_mockup_to_irq(struct gpio_chip *gc, unsigned int offset) return irq_sim_irqnum(&chip->irqsim, offset); } -static ssize_t gpio_mockup_event_write(struct file *file, - const char __user *usr_buf, - size_t size, loff_t *ppos) +static void gpio_mockup_free(struct gpio_chip *gc, unsigned int offset) +{ + struct gpio_mockup_chip *chip = gpiochip_get_data(gc); + + __gpio_mockup_set(chip, offset, chip->lines[offset].pull); +} + +static ssize_t gpio_mockup_debugfs_read(struct file *file, + char __user *usr_buf, + size_t size, loff_t *ppos) { struct gpio_mockup_dbgfs_private *priv; struct gpio_mockup_chip *chip; struct seq_file *sfile; + struct gpio_chip *gc; + char buf[3]; + int val, rv; + + if (*ppos != 0) + return 0; + + sfile = file->private_data; + priv = sfile->private; + chip = priv->chip; + gc = &chip->gc; + + val = gpio_mockup_get(gc, priv->offset); + snprintf(buf, sizeof(buf), "%d\n", val); + + rv = copy_to_user(usr_buf, buf, sizeof(buf)); + if (rv) + return rv; + + return sizeof(buf) - 1; +} + +static ssize_t gpio_mockup_debugfs_write(struct file *file, + const char __user *usr_buf, + size_t size, loff_t *ppos) +{ + struct gpio_mockup_dbgfs_private *priv; + int rv, val, curr, irq, irq_type; + struct gpio_mockup_chip *chip; + struct seq_file *sfile; struct gpio_desc *desc; - int rv, val; + struct gpio_chip *gc; + struct irq_sim *sim; + + if (*ppos != 0) + return -EINVAL; rv = kstrtoint_from_user(usr_buf, size, 0, &val); if (rv) @@ -159,24 +248,70 @@ static ssize_t gpio_mockup_event_write(struct file *file, sfile = file->private_data; priv = sfile->private; - desc = priv->desc; chip = priv->chip; + gc = &chip->gc; + desc = &gc->gpiodev->descs[priv->offset]; + sim = &chip->irqsim; - gpiod_set_value_cansleep(desc, val); - irq_sim_fire(&chip->irqsim, priv->offset); + mutex_lock(&chip->lock); + + if (test_bit(FLAG_REQUESTED, &desc->flags) && + !test_bit(FLAG_IS_OUT, &desc->flags)) { + curr = __gpio_mockup_get(chip, priv->offset); + if (curr == val) + goto out; + + irq = irq_sim_irqnum(sim, priv->offset); + irq_type = irq_get_trigger_type(irq); + + if ((val == 1 && (irq_type & IRQ_TYPE_EDGE_RISING)) || + (val == 0 && (irq_type & IRQ_TYPE_EDGE_FALLING))) + irq_sim_fire(sim, priv->offset); + } + + /* Change the value unless we're actively driving the line. */ + if (!test_bit(FLAG_REQUESTED, &desc->flags) || + !test_bit(FLAG_IS_OUT, &desc->flags)) + __gpio_mockup_set(chip, priv->offset, val); + +out: + chip->lines[priv->offset].pull = val; + mutex_unlock(&chip->lock); return size; } -static int gpio_mockup_event_open(struct inode *inode, struct file *file) +static int gpio_mockup_debugfs_open(struct inode *inode, struct file *file) { return single_open(file, NULL, inode->i_private); } -static const struct file_operations gpio_mockup_event_ops = { +/* + * Each mockup chip is represented by a directory named after the chip's device + * name under /sys/kernel/debug/gpio-mockup/. Each line is represented by + * a file using the line's offset as the name under the chip's directory. + * + * Reading from the line's file yields the current *value*, writing to the + * line's file changes the current *pull*. Default pull for mockup lines is + * down. + * + * Examples: + * - when a line pulled down is requested in output mode and driven high, its + * value will return to 0 once it's released + * - when the line is requested in output mode and driven high, writing 0 to + * the corresponding debugfs file will change the pull to down but the + * reported value will still be 1 until the line is released + * - line requested in input mode always reports the same value as its pull + * configuration + * - when the line is requested in input mode and monitored for events, writing + * the same value to the debugfs file will be a noop, while writing the + * opposite value will generate a dummy interrupt with an appropriate edge + */ +static const struct file_operations gpio_mockup_debugfs_ops = { .owner = THIS_MODULE, - .open = gpio_mockup_event_open, - .write = gpio_mockup_event_write, + .open = gpio_mockup_debugfs_open, + .read = gpio_mockup_debugfs_read, + .write = gpio_mockup_debugfs_write, .llseek = no_llseek, }; @@ -184,7 +319,7 @@ static void gpio_mockup_debugfs_setup(struct device *dev, struct gpio_mockup_chip *chip) { struct gpio_mockup_dbgfs_private *priv; - struct dentry *evfile, *link; + struct dentry *evfile; struct gpio_chip *gc; const char *devname; char *name; @@ -197,10 +332,6 @@ static void gpio_mockup_debugfs_setup(struct device *dev, if (IS_ERR_OR_NULL(chip->dbg_dir)) goto err; - link = debugfs_create_symlink(gc->label, gpio_mockup_dbg_dir, devname); - if (IS_ERR_OR_NULL(link)) - goto err; - for (i = 0; i < gc->ngpio; i++) { name = devm_kasprintf(dev, GFP_KERNEL, "%d", i); if (!name) @@ -215,7 +346,7 @@ static void gpio_mockup_debugfs_setup(struct device *dev, priv->desc = &gc->gpiodev->descs[i]; evfile = debugfs_create_file(name, 0200, chip->dbg_dir, priv, - &gpio_mockup_event_ops); + &gpio_mockup_debugfs_ops); if (IS_ERR_OR_NULL(evfile)) goto err; } @@ -223,7 +354,7 @@ static void gpio_mockup_debugfs_setup(struct device *dev, return; err: - dev_err(dev, "error creating debugfs event files\n"); + dev_err(dev, "error creating debugfs files\n"); } static int gpio_mockup_name_lines(struct device *dev, @@ -283,6 +414,8 @@ static int gpio_mockup_probe(struct platform_device *pdev) return -ENOMEM; } + mutex_init(&chip->lock); + gc = &chip->gc; gc->base = base; gc->ngpio = ngpio; @@ -291,11 +424,13 @@ static int gpio_mockup_probe(struct platform_device *pdev) gc->parent = dev; gc->get = gpio_mockup_get; gc->set = gpio_mockup_set; + gc->get_multiple = gpio_mockup_get_multiple; gc->set_multiple = gpio_mockup_set_multiple; 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; + gc->free = gpio_mockup_free; chip->lines = devm_kcalloc(dev, gc->ngpio, sizeof(*chip->lines), GFP_KERNEL); @@ -369,7 +504,7 @@ static int __init gpio_mockup_init(void) return -EINVAL; } - gpio_mockup_dbg_dir = debugfs_create_dir("gpio-mockup-event", NULL); + gpio_mockup_dbg_dir = debugfs_create_dir("gpio-mockup", NULL); if (IS_ERR_OR_NULL(gpio_mockup_dbg_dir)) gpio_mockup_err("error creating debugfs directory\n"); diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c index 98a20e1594ce..b992f88c5613 100644 --- a/kernel/irq/irq_sim.c +++ b/kernel/irq/irq_sim.c @@ -25,10 +25,22 @@ static void irq_sim_irqunmask(struct irq_data *data) irq_ctx->enabled = true; } +static int irq_sim_set_type(struct irq_data *data, unsigned int type) +{ + /* We only support rising and falling edge trigger types. */ + if (type & ~IRQ_TYPE_EDGE_BOTH) + return -EINVAL; + + irqd_set_trigger_type(data, type); + + return 0; +} + static struct irq_chip irq_sim_irqchip = { .name = "irq_sim", .irq_mask = irq_sim_irqmask, .irq_unmask = irq_sim_irqunmask, + .irq_set_type = irq_sim_set_type, }; static void irq_sim_handle_irq(struct irq_work *work)