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linux/drivers/pwm/sysfs.c

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pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Get rid of pwm->lock PWM devices are not protected against concurrent accesses. The lock in struct pwm_device might let PWM users think it is, but it's actually only protecting the enabled state. Removing this lock should be fine as long as all PWM users are aware that accesses to the PWM device have to be serialized, which seems to be the case for all of them except the sysfs interface. Patch the sysfs code by adding a lock to the pwm_export struct and making sure it's taken for all relevant accesses to the exported PWM device. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-30 22:03:27 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Make use of the DEVICE_ATTR_[RW][WO] macro's For the npwm property the PWM sysfs interface already made use of the DEVICE_ATTR_RO macro. This patch expands this to the other sysfs properties so that the code base is concise and makes use of this helpful macro. This has the advantage of slightly reducing the code size, improving readability and no longer using magic values for permissions. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-26 22:32:37 +01:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Make use of the DEVICE_ATTR_[RW][WO] macro's For the npwm property the PWM sysfs interface already made use of the DEVICE_ATTR_RO macro. This patch expands this to the other sysfs properties so that the code base is concise and makes use of this helpful macro. This has the advantage of slightly reducing the code size, improving readability and no longer using magic values for permissions. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-26 22:32:37 +01:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Get rid of pwm->lock PWM devices are not protected against concurrent accesses. The lock in struct pwm_device might let PWM users think it is, but it's actually only protecting the enabled state. Removing this lock should be fine as long as all PWM users are aware that accesses to the PWM device have to be serialized, which seems to be the case for all of them except the sysfs interface. Patch the sysfs code by adding a lock to the pwm_export struct and making sure it's taken for all relevant accesses to the exported PWM device. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-30 22:03:27 +02:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Get rid of pwm->lock PWM devices are not protected against concurrent accesses. The lock in struct pwm_device might let PWM users think it is, but it's actually only protecting the enabled state. Removing this lock should be fine as long as all PWM users are aware that accesses to the PWM device have to be serialized, which seems to be the case for all of them except the sysfs interface. Patch the sysfs code by adding a lock to the pwm_export struct and making sure it's taken for all relevant accesses to the exported PWM device. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-30 22:03:27 +02:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Get rid of pwm->lock PWM devices are not protected against concurrent accesses. The lock in struct pwm_device might let PWM users think it is, but it's actually only protecting the enabled state. Removing this lock should be fine as long as all PWM users are aware that accesses to the PWM device have to be serialized, which seems to be the case for all of them except the sysfs interface. Patch the sysfs code by adding a lock to the pwm_export struct and making sure it's taken for all relevant accesses to the exported PWM device. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-30 22:03:27 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Make use of the DEVICE_ATTR_[RW][WO] macro's For the npwm property the PWM sysfs interface already made use of the DEVICE_ATTR_RO macro. This patch expands this to the other sysfs properties so that the code base is concise and makes use of this helpful macro. This has the advantage of slightly reducing the code size, improving readability and no longer using magic values for permissions. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-26 22:32:37 +01:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Make use of the DEVICE_ATTR_[RW][WO] macro's For the npwm property the PWM sysfs interface already made use of the DEVICE_ATTR_RO macro. This patch expands this to the other sysfs properties so that the code base is concise and makes use of this helpful macro. This has the advantage of slightly reducing the code size, improving readability and no longer using magic values for permissions. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-26 22:32:37 +01:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Get rid of pwm->lock PWM devices are not protected against concurrent accesses. The lock in struct pwm_device might let PWM users think it is, but it's actually only protecting the enabled state. Removing this lock should be fine as long as all PWM users are aware that accesses to the PWM device have to be serialized, which seems to be the case for all of them except the sysfs interface. Patch the sysfs code by adding a lock to the pwm_export struct and making sure it's taken for all relevant accesses to the exported PWM device. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-30 22:03:27 +02:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Get rid of pwm->lock PWM devices are not protected against concurrent accesses. The lock in struct pwm_device might let PWM users think it is, but it's actually only protecting the enabled state. Removing this lock should be fine as long as all PWM users are aware that accesses to the PWM device have to be serialized, which seems to be the case for all of them except the sysfs interface. Patch the sysfs code by adding a lock to the pwm_export struct and making sure it's taken for all relevant accesses to the exported PWM device. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-30 22:03:27 +02:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Get rid of pwm->lock PWM devices are not protected against concurrent accesses. The lock in struct pwm_device might let PWM users think it is, but it's actually only protecting the enabled state. Removing this lock should be fine as long as all PWM users are aware that accesses to the PWM device have to be serialized, which seems to be the case for all of them except the sysfs interface. Patch the sysfs code by adding a lock to the pwm_export struct and making sure it's taken for all relevant accesses to the exported PWM device. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-30 22:03:27 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Make use of the DEVICE_ATTR_[RW][WO] macro's For the npwm property the PWM sysfs interface already made use of the DEVICE_ATTR_RO macro. This patch expands this to the other sysfs properties so that the code base is concise and makes use of this helpful macro. This has the advantage of slightly reducing the code size, improving readability and no longer using magic values for permissions. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-26 22:32:37 +01:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Make use of the DEVICE_ATTR_[RW][WO] macro's For the npwm property the PWM sysfs interface already made use of the DEVICE_ATTR_RO macro. This patch expands this to the other sysfs properties so that the code base is concise and makes use of this helpful macro. This has the advantage of slightly reducing the code size, improving readability and no longer using magic values for permissions. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-26 22:32:37 +01:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Get rid of pwm->lock PWM devices are not protected against concurrent accesses. The lock in struct pwm_device might let PWM users think it is, but it's actually only protecting the enabled state. Removing this lock should be fine as long as all PWM users are aware that accesses to the PWM device have to be serialized, which seems to be the case for all of them except the sysfs interface. Patch the sysfs code by adding a lock to the pwm_export struct and making sure it's taken for all relevant accesses to the exported PWM device. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-30 22:03:27 +02:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Get rid of pwm->lock PWM devices are not protected against concurrent accesses. The lock in struct pwm_device might let PWM users think it is, but it's actually only protecting the enabled state. Removing this lock should be fine as long as all PWM users are aware that accesses to the PWM device have to be serialized, which seems to be the case for all of them except the sysfs interface. Patch the sysfs code by adding a lock to the pwm_export struct and making sure it's taken for all relevant accesses to the exported PWM device. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-30 22:03:27 +02:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Get return value from pwm_apply_state() This patch adds to check the return value from pwm_apply_state() used in enable_store(). The error of enable_store() doesn't work if the return value doesn't received. Signed-off-by: Ryo Kodama <ryo.kodama.vz@renesas.com> Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com> Fixes: 39100ceea79f ("pwm: Switch to the atomic API") Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-06-08 10:58:23 +09:00
pwm: Get rid of pwm->lock PWM devices are not protected against concurrent accesses. The lock in struct pwm_device might let PWM users think it is, but it's actually only protecting the enabled state. Removing this lock should be fine as long as all PWM users are aware that accesses to the PWM device have to be serialized, which seems to be the case for all of them except the sysfs interface. Patch the sysfs code by adding a lock to the pwm_export struct and making sure it's taken for all relevant accesses to the exported PWM device. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-30 22:03:27 +02:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Make use of the DEVICE_ATTR_[RW][WO] macro's For the npwm property the PWM sysfs interface already made use of the DEVICE_ATTR_RO macro. This patch expands this to the other sysfs properties so that the code base is concise and makes use of this helpful macro. This has the advantage of slightly reducing the code size, improving readability and no longer using magic values for permissions. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-26 22:32:37 +01:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Properly convert from enum to string The current code will check for polarity in a boolean way. While it is correct that polarity is either normal or inversed, make it more obvious that it's an enumeration by using a switch statement and explicit matches on the enumeration values. Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-07-20 09:56:05 +02:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: sysfs: Properly convert from enum to string The current code will check for polarity in a boolean way. While it is correct that polarity is either normal or inversed, make it more obvious that it's an enumeration by using a switch statement and explicit matches on the enumeration values. Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-07-20 09:56:05 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Make use of the DEVICE_ATTR_[RW][WO] macro's For the npwm property the PWM sysfs interface already made use of the DEVICE_ATTR_RO macro. This patch expands this to the other sysfs properties so that the code base is concise and makes use of this helpful macro. This has the advantage of slightly reducing the code size, improving readability and no longer using magic values for permissions. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-26 22:32:37 +01:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Get rid of pwm->lock PWM devices are not protected against concurrent accesses. The lock in struct pwm_device might let PWM users think it is, but it's actually only protecting the enabled state. Removing this lock should be fine as long as all PWM users are aware that accesses to the PWM device have to be serialized, which seems to be the case for all of them except the sysfs interface. Patch the sysfs code by adding a lock to the pwm_export struct and making sure it's taken for all relevant accesses to the exported PWM device. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-30 22:03:27 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Get rid of pwm->lock PWM devices are not protected against concurrent accesses. The lock in struct pwm_device might let PWM users think it is, but it's actually only protecting the enabled state. Removing this lock should be fine as long as all PWM users are aware that accesses to the PWM device have to be serialized, which seems to be the case for all of them except the sysfs interface. Patch the sysfs code by adding a lock to the pwm_export struct and making sure it's taken for all relevant accesses to the exported PWM device. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-30 22:03:27 +02:00
pwm: Switch to the atomic API Replace legacy pwm_get/set_xxx() and pwm_config/enable/disable() calls by pwm_get/apply_state(). Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-04-14 21:17:43 +02:00
pwm: Get rid of pwm->lock PWM devices are not protected against concurrent accesses. The lock in struct pwm_device might let PWM users think it is, but it's actually only protecting the enabled state. Removing this lock should be fine as long as all PWM users are aware that accesses to the PWM device have to be serialized, which seems to be the case for all of them except the sysfs interface. Patch the sysfs code by adding a lock to the pwm_export struct and making sure it's taken for all relevant accesses to the exported PWM device. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-30 22:03:27 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Add PWM capture support Allow a user to read PWM capture results from sysfs. To start a capture and read the result, simply read the file: $ cat $PWMCHIP/capture The output format is "<period> <duty cycle>". Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-06-08 10:21:25 +01:00
pwm: sysfs: Make use of the DEVICE_ATTR_[RW][WO] macro's For the npwm property the PWM sysfs interface already made use of the DEVICE_ATTR_RO macro. This patch expands this to the other sysfs properties so that the code base is concise and makes use of this helpful macro. This has the advantage of slightly reducing the code size, improving readability and no longer using magic values for permissions. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-26 22:32:37 +01:00
pwm: sysfs: Add PWM capture support Allow a user to read PWM capture results from sysfs. To start a capture and read the result, simply read the file: $ cat $PWMCHIP/capture The output format is "<period> <duty cycle>". Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-06-08 10:21:25 +01:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Add PWM capture support Allow a user to read PWM capture results from sysfs. To start a capture and read the result, simply read the file: $ cat $PWMCHIP/capture The output format is "<period> <duty cycle>". Signed-off-by: Lee Jones <lee.jones@linaro.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-06-08 10:21:25 +01:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Convert to use ATTRIBUTE_GROUPS macro Use new ATTRIBUTE_GROUPS macro to reduce the number of lines of code. Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-12-04 18:29:53 +08:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Get rid of pwm->lock PWM devices are not protected against concurrent accesses. The lock in struct pwm_device might let PWM users think it is, but it's actually only protecting the enabled state. Removing this lock should be fine as long as all PWM users are aware that accesses to the PWM device have to be serialized, which seems to be the case for all of them except the sysfs interface. Patch the sysfs code by adding a lock to the pwm_export struct and making sure it's taken for all relevant accesses to the exported PWM device. Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-03-30 22:03:27 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Convert to use ATTRIBUTE_GROUPS macro Use new ATTRIBUTE_GROUPS macro to reduce the number of lines of code. Signed-off-by: Axel Lin <axel.lin@ingics.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-12-04 18:29:53 +08:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Make use of the DEVICE_ATTR_[RW][WO] macro's For the npwm property the PWM sysfs interface already made use of the DEVICE_ATTR_RO macro. This patch expands this to the other sysfs properties so that the code base is concise and makes use of this helpful macro. This has the advantage of slightly reducing the code size, improving readability and no longer using magic values for permissions. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-26 22:32:37 +01:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Make use of the DEVICE_ATTR_[RW][WO] macro's For the npwm property the PWM sysfs interface already made use of the DEVICE_ATTR_RO macro. This patch expands this to the other sysfs properties so that the code base is concise and makes use of this helpful macro. This has the advantage of slightly reducing the code size, improving readability and no longer using magic values for permissions. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-26 22:32:37 +01:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Make use of the DEVICE_ATTR_[RW][WO] macro's For the npwm property the PWM sysfs interface already made use of the DEVICE_ATTR_RO macro. This patch expands this to the other sysfs properties so that the code base is concise and makes use of this helpful macro. This has the advantage of slightly reducing the code size, improving readability and no longer using magic values for permissions. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-26 22:32:37 +01:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Make use of the DEVICE_ATTR_[RW][WO] macro's For the npwm property the PWM sysfs interface already made use of the DEVICE_ATTR_RO macro. This patch expands this to the other sysfs properties so that the code base is concise and makes use of this helpful macro. This has the advantage of slightly reducing the code size, improving readability and no longer using magic values for permissions. Signed-off-by: Olliver Schinagl <oliver@schinagl.nl> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-10-26 22:32:37 +01:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: convert class code to use dev_groups The dev_attrs field of struct class is going away soon, dev_groups should be used instead. This converts the PWM class code to use the correct field. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-07-24 15:05:39 -07:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: convert class code to use dev_groups The dev_attrs field of struct class is going away soon, dev_groups should be used instead. This converts the PWM class code to use the correct field. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-07-24 15:05:39 -07:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: convert class code to use dev_groups The dev_attrs field of struct class is going away soon, dev_groups should be used instead. This converts the PWM class code to use the correct field. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-07-24 15:05:39 -07:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: convert class code to use dev_groups The dev_attrs field of struct class is going away soon, dev_groups should be used instead. This converts the PWM class code to use the correct field. Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-07-24 15:05:39 -07:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: sysfs: Remove unnecessary padding Padding initializers so that assignment operators align is bound to lead to inconsistencies or churn. Single spaces around the assignment is just fine. Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2015-07-20 09:58:09 +02:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00
pwm: Unexport children before chip removal Exported pwm channels aren't removed before the pwmchip and are leaked. This results in invalid sysfs files. This fix removes all exported pwm channels before chip removal. Signed-off-by: David Hsu <davidhsu@google.com> Fixes: 76abbdde2d95 ("pwm: Add sysfs interface") Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-08-09 14:57:46 -07:00
pwm: Fix device reference leak Make sure to drop the reference to the parent device taken by class_find_device() after "unexporting" any children when deregistering a PWM chip. Fixes: 0733424c9ba9 ("pwm: Unexport children before chip removal") Signed-off-by: Johan Hovold <johan@kernel.org> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-11-01 11:46:39 +01:00
pwm: Unexport children before chip removal Exported pwm channels aren't removed before the pwmchip and are leaked. This results in invalid sysfs files. This fix removes all exported pwm channels before chip removal. Signed-off-by: David Hsu <davidhsu@google.com> Fixes: 76abbdde2d95 ("pwm: Add sysfs interface") Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2016-08-09 14:57:46 -07:00
pwm: Add sysfs interface Add a simple sysfs interface to the generic PWM framework. /sys/class/pwm/ `-- pwmchipN/ for each PWM chip |-- export (w/o) ask the kernel to export a PWM channel |-- npwm (r/o) number of PWM channels in this PWM chip |-- pwmX/ for each exported PWM channel | |-- duty_cycle (r/w) duty cycle (in nanoseconds) | |-- enable (r/w) enable/disable PWM | |-- period (r/w) period (in nanoseconds) | `-- polarity (r/w) polarity of PWM (normal/inversed) `-- unexport (w/o) return a PWM channel to the kernel Based on work by Lars Poeschel. Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lars Poeschel <poeschel@lemonage.de> Cc: Ryan Mallon <rmallon@gmail.com> Cc: Rob Landley <rob@landley.net> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2013-06-11 10:38:59 -07:00