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authorLinus Torvalds <torvalds@linux-foundation.org>2012-10-10 20:15:24 +0900
committerLinus Torvalds <torvalds@linux-foundation.org>2012-10-10 20:15:24 +0900
commit2474542f64432398f503373f53bdf620491bcfa8 (patch)
tree3c9744b138c2158757530814b35c23eed31cf6ce /include/linux
parentc7a6ced9d8e8411bdafe83998474d185a79badc3 (diff)
parent85f8879ca4f3d26a7f473522101fb74a79bda3f2 (diff)
Merge tag 'for-3.7-rc1' of git://gitorious.org/linux-pwm/linux-pwm
Pull pwm changes from Thierry Reding: "All legacy PWM providers have now been moved to the PWM subsystem. The plan for 3.8 is to adapt all board files to provide a lookup table for PWM devices in order to get rid of the global namespace. Subsequently, users of the legacy pwm_request() and pwm_free() functions can be migrated to the new pwm_get() and pwm_put() functions. Once this has been completed, the legacy API and the compatibility code in the core can be removed. In addition to the above, these changes also add support for configuring the polarity of a PWM signal (currently only supported on ECAP and EHRPWM) and include a much needed rework of the i.MX driver. Managed functions to obtain and release a PWM device (devm_pwm_get() and devm_pwm_put()) have been added and the pwm-backlight driver has been updated to use them. If the PWM subsystem hasn't been enabled, dummy functions are provided that allow the subsystem to safely compile out. Some common checks on input parameters have been moved to the core and removed from the drivers. Finally, a small fix corrects the description of the PWM specifier's second cell in the device tree representation." * tag 'for-3.7-rc1' of git://gitorious.org/linux-pwm/linux-pwm: (23 commits) pwm: dt: Fix description of second PWM cell pwm: Check for negative duty-cycle and period pwm: Add Ingenic JZ4740 support MIPS: JZ4740: Export timer API pwm: Move PUV3 PWM driver to PWM framework unicore32: pwm: Use managed resource allocations unicore32: pwm: Remove unnecessary indirection unicore32: pwm: Use module_platform_driver() unicore32: pwm: Properly remap memory-mapped registers pwm-backlight: Use devm_pwm_get() instead of pwm_get() pwm: Move AB8500 PWM driver to PWM framework pwm: Fix compilation error when CONFIG_PWM is not defined pwm: i.MX: fix clock lookup pwm: i.MX: use per clock unconditionally pwm: i.MX: add devicetree support pwm: i.MX: Use module_platform_driver pwm: i.MX: add functions to enable/disable pwm. pwm: i.MX: remove unnecessary if in pwm_[en|dis]able pwm: i.MX: factor out SoC specific functions pwm: pwm-tiehrpwm: Add support for configuring polarity of PWM ...
Diffstat (limited to 'include/linux')
-rw-r--r--include/linux/pwm.h108
1 files changed, 106 insertions, 2 deletions
diff --git a/include/linux/pwm.h b/include/linux/pwm.h
index 21d076c5089..112b3143684 100644
--- a/include/linux/pwm.h
+++ b/include/linux/pwm.h
@@ -1,11 +1,13 @@
#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
*/
@@ -30,10 +32,47 @@ 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
-#ifdef CONFIG_PWM
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,
@@ -61,11 +100,17 @@ 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
@@ -79,6 +124,9 @@ struct pwm_ops {
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,
@@ -113,6 +161,7 @@ struct pwm_chip {
unsigned int of_pwm_n_cells;
};
+#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);
@@ -125,6 +174,57 @@ struct pwm_device *pwm_request_from_chip(struct pwm_chip *chip,
struct pwm_device *pwm_get(struct device *dev, const char *consumer);
void pwm_put(struct pwm_device *pwm);
+struct pwm_device *devm_pwm_get(struct device *dev, const char *consumer);
+void devm_pwm_put(struct device *dev, 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 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 void devm_pwm_put(struct device *dev, struct pwm_device *pwm)
+{
+}
+#endif
+
struct pwm_lookup {
struct list_head list;
const char *provider;
@@ -141,8 +241,12 @@ struct pwm_lookup {
.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 */