diff --git a/drivers/pwm/core.c b/drivers/pwm/core.c index a447be128328..aadc1d797449 100644 --- a/drivers/pwm/core.c +++ b/drivers/pwm/core.c @@ -27,6 +27,8 @@ #include #include #include +#include +#include #define MAX_PWMS 1024 @@ -338,3 +340,91 @@ void pwm_disable(struct pwm_device *pwm) pwm->chip->ops->disable(pwm->chip, pwm); } EXPORT_SYMBOL_GPL(pwm_disable); + +#ifdef CONFIG_DEBUG_FS +static void pwm_dbg_show(struct pwm_chip *chip, struct seq_file *s) +{ + unsigned int i; + + for (i = 0; i < chip->npwm; i++) { + struct pwm_device *pwm = &chip->pwms[i]; + + seq_printf(s, " pwm-%-3d (%-20.20s):", i, pwm->label); + + if (test_bit(PWMF_REQUESTED, &pwm->flags)) + seq_printf(s, " requested"); + + if (test_bit(PWMF_ENABLED, &pwm->flags)) + seq_printf(s, " enabled"); + + seq_printf(s, "\n"); + } +} + +static void *pwm_seq_start(struct seq_file *s, loff_t *pos) +{ + mutex_lock(&pwm_lock); + s->private = ""; + + return seq_list_start(&pwm_chips, *pos); +} + +static void *pwm_seq_next(struct seq_file *s, void *v, loff_t *pos) +{ + s->private = "\n"; + + return seq_list_next(v, &pwm_chips, pos); +} + +static void pwm_seq_stop(struct seq_file *s, void *v) +{ + mutex_unlock(&pwm_lock); +} + +static int pwm_seq_show(struct seq_file *s, void *v) +{ + struct pwm_chip *chip = list_entry(v, struct pwm_chip, list); + + seq_printf(s, "%s%s/%s, %d PWM device%s\n", (char *)s->private, + chip->dev->bus ? chip->dev->bus->name : "no-bus", + dev_name(chip->dev), chip->npwm, + (chip->npwm != 1) ? "s" : ""); + + if (chip->ops->dbg_show) + chip->ops->dbg_show(chip, s); + else + pwm_dbg_show(chip, s); + + return 0; +} + +static const struct seq_operations pwm_seq_ops = { + .start = pwm_seq_start, + .next = pwm_seq_next, + .stop = pwm_seq_stop, + .show = pwm_seq_show, +}; + +static int pwm_seq_open(struct inode *inode, struct file *file) +{ + return seq_open(file, &pwm_seq_ops); +} + +static const struct file_operations pwm_debugfs_ops = { + .owner = THIS_MODULE, + .open = pwm_seq_open, + .read = seq_read, + .llseek = seq_lseek, + .release = seq_release, +}; + +static int __init pwm_debugfs_init(void) +{ + debugfs_create_file("pwm", S_IFREG | S_IRUGO, NULL, NULL, + &pwm_debugfs_ops); + + return 0; +} + +subsys_initcall(pwm_debugfs_init); +#endif /* CONFIG_DEBUG_FS */ diff --git a/include/linux/pwm.h b/include/linux/pwm.h index 57103911f4c7..047cd5351a3b 100644 --- a/include/linux/pwm.h +++ b/include/linux/pwm.h @@ -2,6 +2,7 @@ #define __LINUX_PWM_H struct pwm_device; +struct seq_file; /* * pwm_request - request a PWM device @@ -65,6 +66,7 @@ static inline unsigned int pwm_get_period(struct pwm_device *pwm) * @config: configure duty cycles and period length for this PWM * @enable: enable PWM output toggling * @disable: disable PWM output toggling + * @dbg_show: optional routine to show contents in debugfs * @owner: helps prevent removal of modules exporting active PWMs */ struct pwm_ops { @@ -79,6 +81,10 @@ struct pwm_ops { struct pwm_device *pwm); void (*disable)(struct pwm_chip *chip, struct pwm_device *pwm); +#ifdef CONFIG_DEBUG_FS + void (*dbg_show)(struct pwm_chip *chip, + struct seq_file *s); +#endif struct module *owner; };