first commit

1 files changed, 281 insertions, 0 deletions

diff --git a/include/linux/pwm.h b/include/linux/pwm.h
new file mode 100644
index 000000000..a4df2042b
--- /dev/null
+++ b/include/linux/pwm.h
@@ -0,0 +1,281 @@
+#ifndef __LINUX_PWM_H
+#define __LINUX_PWM_H
+
+#include <linux/err.h>
+#include <linux/of.h>
+
+struct pwm_device;
+struct seq_file;
+
+#if IS_ENABLED(CONFIG_PWM) || IS_ENABLED(CONFIG_HAVE_PWM)
+/*
+ * pwm_request - request a PWM device
+ */
+struct pwm_device *pwm_request(int pwm_id, const char *label);
+
+/*
+ * pwm_free - free a PWM device
+ */
+void pwm_free(struct pwm_device *pwm);
+
+/*
+ * pwm_config - change a PWM device configuration
+ */
+int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns);
+
+/*
+ * pwm_enable - start a PWM output toggling
+ */
+int pwm_enable(struct pwm_device *pwm);
+
+/*
+ * pwm_disable - stop a PWM output toggling
+ */
+void pwm_disable(struct pwm_device *pwm);
+#else
+static inline struct pwm_device *pwm_request(int pwm_id, const char *label)
+{
+	return ERR_PTR(-ENODEV);
+}
+
+static inline void pwm_free(struct pwm_device *pwm)
+{
+}
+
+static inline int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
+{
+	return -EINVAL;
+}
+
+static inline int pwm_enable(struct pwm_device *pwm)
+{
+	return -EINVAL;
+}
+
+static inline void pwm_disable(struct pwm_device *pwm)
+{
+}
+#endif
+
+struct pwm_chip;
+
+/**
+ * enum pwm_polarity - polarity of a PWM signal
+ * @PWM_POLARITY_NORMAL: a high signal for the duration of the duty-
+ * cycle, followed by a low signal for the remainder of the pulse
+ * period
+ * @PWM_POLARITY_INVERSED: a low signal for the duration of the duty-
+ * cycle, followed by a high signal for the remainder of the pulse
+ * period
+ */
+enum pwm_polarity {
+	PWM_POLARITY_NORMAL,
+	PWM_POLARITY_INVERSED,
+};
+
+enum {
+	PWMF_REQUESTED = 1 << 0,
+	PWMF_ENABLED = 1 << 1,
+};
+
+struct pwm_device {
+	const char		*label;
+	unsigned long		flags;
+	unsigned int		hwpwm;
+	unsigned int		pwm;
+	struct pwm_chip		*chip;
+	void			*chip_data;
+
+	unsigned int		period; /* in nanoseconds */
+};
+
+static inline void pwm_set_period(struct pwm_device *pwm, unsigned int period)
+{
+	if (pwm)
+		pwm->period = period;
+}
+
+static inline unsigned int pwm_get_period(struct pwm_device *pwm)
+{
+	return pwm ? pwm->period : 0;
+}
+
+/*
+ * pwm_set_polarity - configure the polarity of a PWM signal
+ */
+int pwm_set_polarity(struct pwm_device *pwm, enum pwm_polarity polarity);
+
+/**
+ * struct pwm_ops - PWM controller operations
+ * @request: optional hook for requesting a PWM
+ * @free: optional hook for freeing a PWM
+ * @config: configure duty cycles and period length for this PWM
+ * @set_polarity: configure the polarity of 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 {
+	int			(*request)(struct pwm_chip *chip,
+					   struct pwm_device *pwm);
+	void			(*free)(struct pwm_chip *chip,
+					struct pwm_device *pwm);
+	int			(*config)(struct pwm_chip *chip,
+					  struct pwm_device *pwm,
+					  int duty_ns, int period_ns);
+	int			(*set_polarity)(struct pwm_chip *chip,
+					  struct pwm_device *pwm,
+					  enum pwm_polarity polarity);
+	int			(*enable)(struct pwm_chip *chip,
+					  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;
+};
+
+/**
+ * struct pwm_chip - abstract a PWM controller
+ * @dev: device providing the PWMs
+ * @list: list node for internal use
+ * @ops: callbacks for this PWM controller
+ * @base: number of first PWM controlled by this chip
+ * @npwm: number of PWMs controlled by this chip
+ * @pwms: array of PWM devices allocated by the framework
+ * @can_sleep: must be true if the .config(), .enable() or .disable()
+ *             operations may sleep
+ */
+struct pwm_chip {
+	struct device		*dev;
+	struct list_head	list;
+	const struct pwm_ops	*ops;
+	int			base;
+	unsigned int		npwm;
+
+	struct pwm_device	*pwms;
+
+	struct pwm_device *	(*of_xlate)(struct pwm_chip *pc,
+					    const struct of_phandle_args *args);
+	unsigned int		of_pwm_n_cells;
+	bool			can_sleep;
+};
+
+#if IS_ENABLED(CONFIG_PWM)
+int pwm_set_chip_data(struct pwm_device *pwm, void *data);
+void *pwm_get_chip_data(struct pwm_device *pwm);
+
+int pwmchip_add(struct pwm_chip *chip);
+int pwmchip_remove(struct pwm_chip *chip);
+struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip,
+					 unsigned int index,
+					 const char *label);
+
+struct pwm_device *of_pwm_xlate_with_flags(struct pwm_chip *pc,
+		const struct of_phandle_args *args);
+
+struct pwm_device *pwm_get(struct device *dev, const char *con_id);
+struct pwm_device *of_pwm_get(struct device_node *np, const char *con_id);
+void pwm_put(struct pwm_device *pwm);
+
+struct pwm_device *devm_pwm_get(struct device *dev, const char *con_id);
+struct pwm_device *devm_of_pwm_get(struct device *dev, struct device_node *np,
+				   const char *con_id);
+void devm_pwm_put(struct device *dev, struct pwm_device *pwm);
+
+bool pwm_can_sleep(struct pwm_device *pwm);
+#else
+static inline int pwm_set_chip_data(struct pwm_device *pwm, void *data)
+{
+	return -EINVAL;
+}
+
+static inline void *pwm_get_chip_data(struct pwm_device *pwm)
+{
+	return NULL;
+}
+
+static inline int pwmchip_add(struct pwm_chip *chip)
+{
+	return -EINVAL;
+}
+
+static inline int pwmchip_remove(struct pwm_chip *chip)
+{
+	return -EINVAL;
+}
+
+static inline struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip,
+						       unsigned int index,
+						       const char *label)
+{
+	return ERR_PTR(-ENODEV);
+}
+
+static inline struct pwm_device *pwm_get(struct device *dev,
+					 const char *consumer)
+{
+	return ERR_PTR(-ENODEV);
+}
+
+static inline struct pwm_device *of_pwm_get(struct device_node *np,
+					    const char *con_id)
+{
+	return ERR_PTR(-ENODEV);
+}
+
+static inline void pwm_put(struct pwm_device *pwm)
+{
+}
+
+static inline struct pwm_device *devm_pwm_get(struct device *dev,
+					      const char *consumer)
+{
+	return ERR_PTR(-ENODEV);
+}
+
+static inline struct pwm_device *devm_of_pwm_get(struct device *dev,
+						 struct device_node *np,
+						 const char *con_id)
+{
+	return ERR_PTR(-ENODEV);
+}
+
+static inline void devm_pwm_put(struct device *dev, struct pwm_device *pwm)
+{
+}
+
+static inline bool pwm_can_sleep(struct pwm_device *pwm)
+{
+	return false;
+}
+#endif
+
+struct pwm_lookup {
+	struct list_head list;
+	const char *provider;
+	unsigned int index;
+	const char *dev_id;
+	const char *con_id;
+};
+
+#define PWM_LOOKUP(_provider, _index, _dev_id, _con_id)	\
+	{						\
+		.provider = _provider,			\
+		.index = _index,			\
+		.dev_id = _dev_id,			\
+		.con_id = _con_id,			\
+	}
+
+#if IS_ENABLED(CONFIG_PWM)
+void pwm_add_table(struct pwm_lookup *table, size_t num);
+#else
+static inline void pwm_add_table(struct pwm_lookup *table, size_t num)
+{
+}
+#endif
+
+#endif /* __LINUX_PWM_H */