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2022-09-19pwm: core: Get rid of unused devm_of_pwm_get()Andy Shevchenko1-2/+1
The devm_of_pwm_get() has recently lost its single user, drop the dead API as well. Note, the new code should use either plain pwm_get() or managed devm_pwm_get() or devm_fwnode_pwm_get() APIs. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Acked-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Link: https://lore.kernel.org/r/20220826172642.16404-2-andriy.shevchenko@linux.intel.com Signed-off-by: Guenter Roeck <linux@roeck-us.net>
2022-05-20pwm: Document that the pinstate of a disabled PWM isn't reliableUwe Kleine-König1-0/+6
Some (most?) drivers emit the inactive state when the PWM is disabled. However there are exceptions, so document that a consumer better doesn't depend on this behaviour. Some known exceptions: - imx27 emits 0 independent of the configured polarity - mxs just drives the output to the last emitted state. - iqs620a makes the output tristated on disable, so an external pull-down would be required. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Acked-by: Alexander Stein <alexander.stein@ew.tq-group.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-30pwm: core: Remove unused devm_pwm_put()Andy Shevchenko1-1/+2
There are no users and seems no will come of the devm_pwm_put(). Remove the function. While at it, slightly update documentation. Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-06-04pwm: core: Support new usage_power setting in PWM stateClemens Gruber1-0/+4
If usage_power is set, the PWM driver is only required to maintain the power output but has more freedom regarding signal form. If supported, the signal can be optimized, for example to improve EMI by phase shifting individual channels. Signed-off-by: Clemens Gruber <clemens.gruber@pqgruber.com> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-04-26pwm: Reword docs about pwm_apply_state()Uwe Kleine-König1-5/+5
The main issue is that the current documentation talks about the non-existent function pwm_get_last_applied_state. (This was right in the context of https://lore.kernel.org/linux-pwm/20210406073036.26857-1-u.kleine-koenig@pengutronix.de/ but was then missed to adapt when this patch was reduced to a documentation update.) While at is also clarify "last applied PWM state" to "PWM state that was passed to the last invocation of pwm_apply_state()" to better distinguish to the last actually implemented state and reword to drop a word repetition. Fixes: 1a7a6e8072ea ("pwm: Clarify which state pwm_get_state() returns") Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2021-04-09pwm: Clarify which state pwm_get_state() returnsUwe Kleine-König1-1/+5
Given that lowlevel drivers usually cannot implement exactly what a consumer requests with pwm_apply_state() there is some rounding involved. pwm_get_state() returns the setting that was requested most recently by the consumer (opposed to what was actually implemented in hardware in reply to the last request). Clarify this in the function kerneldoc. Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de> Signed-off-by: Thierry Reding <thierry.reding@gmail.com>
2019-07-15docs: driver-api: add a series of orphaned documentsMauro Carvalho Chehab1-0/+165
There are lots of documents under Documentation/*.txt and a few other orphan documents elsehwere that belong to the driver-API book. Move them to their right place. Reviewed-by: Cornelia Huck <cohuck@redhat.com> # vfio-related parts Acked-by: Logan Gunthorpe <logang@deltatee.com> # switchtec Signed-off-by: Mauro Carvalho Chehab <mchehab+samsung@kernel.org>