kernel/drivers/pwm/sysfs.c, branch linux-6.9.y

pwm: Provide an inline function to get the parent device of a given chip

2024-02-15T11:37:29Z

Currently a pwm_chip stores in its struct device *dev member a pointer to the parent device. Preparing a change that embeds a full struct device in struct pwm_chip, this accessor function should be used in all drivers directly accessing chip->dev now. This way struct pwm_chip and this new function can be changed without having to touch all drivers in the same change set. Make use of this function in the framework's core sources. Reviewed-by: Greg Kroah-Hartman Link: https://lore.kernel.org/r/cc30090d2f9762bed9854a55612144bccc910781.1707900770.git.u.kleine-koenig@pengutronix.de Signed-off-by: Uwe Kleine-König

pwm: Rename pwm_apply_state() to pwm_apply_might_sleep()

2023-12-20T15:07:04Z

In order to introduce a pwm api which can be used from atomic context, we will need two functions for applying pwm changes: int pwm_apply_might_sleep(struct pwm *, struct pwm_state *); int pwm_apply_atomic(struct pwm *, struct pwm_state *); This commit just deals with renaming pwm_apply_state(), a following commit will introduce the pwm_apply_atomic() function. Acked-by: Uwe Kleine-König Acked-by: Guenter Roeck Acked-by: Mark Brown Acked-by: Dmitry Torokhov # for input Acked-by: Hans de Goede Acked-by: Jani Nikula Acked-by: Lee Jones Signed-off-by: Sean Young Signed-off-by: Thierry Reding

pwm: Replace PWM chip unique base by unique ID

2023-12-20T15:04:12Z

Traditionally each PWM device had a unique ID stored in the "pwm" member of struct pwm_device. However this number was hardly used and dropped in the previous commit. To identify a certain PWM you're supposed to use the chip's ID and the hwpwm of the PWM device now. With the PWM chip base gone PWM chips can get their IDs better and simpler using an idr. This is expected to change the numbering of PWM chips, but nothing should rely on the numbering anyhow. Other than that the side effects are: - The PWM chip IDs are smaller and in most cases consecutive. - The ordering in /sys/kernel/debug/pwm is ordered by ascending PWM chip ID. Signed-off-by: Uwe Kleine-König Signed-off-by: Thierry Reding

pwm: sysfs: Do not apply state to already disabled PWMs

2023-06-23T13:42:58Z

If the PWM is exported but not enabled, do not call pwm_class_apply_state(). First of all, in this case, period may still be unconfigured and this would make pwm_class_apply_state() return -EINVAL, and then suspend would fail. Second, it makes little sense to apply state onto PWM that is not enabled before suspend. Failing case: " $ echo 1 > /sys/class/pwm/pwmchip4/export $ echo mem > /sys/power/state ... pwm pwmchip4: PM: dpm_run_callback(): pwm_class_suspend+0x1/0xa8 returns -22 pwm pwmchip4: PM: failed to suspend: error -22 PM: Some devices failed to suspend, or early wake event detected " Working case: " $ echo 1 > /sys/class/pwm/pwmchip4/export $ echo 100 > /sys/class/pwm/pwmchip4/pwm1/period $ echo 10 > /sys/class/pwm/pwmchip4/pwm1/duty_cycle $ echo mem > /sys/power/state ... " Do not call pwm_class_apply_state() in case the PWM is disabled to fix this issue. Fixes: 7fd4edc57bbae ("pwm: sysfs: Add suspend/resume support") Signed-off-by: Marek Vasut Fixes: ef2bf4997f7d ("pwm: Improve args checking in pwm_apply_state()") Reviewed-by: Brian Norris Reviewed-by: Uwe Kleine-König Signed-off-by: Thierry Reding

drivers: remove struct module * setting from struct class

2023-03-17T14:16:27Z

There is no need to manually set the owner of a struct class, as the registering function does it automatically, so remove all of the explicit settings from various drivers that did so as it is unneeded. This allows us to remove this pointer entirely from this structure going forward. Cc: "Rafael J. Wysocki" Link: https://lore.kernel.org/r/20230313181843.1207845-2-gregkh@linuxfoundation.org Signed-off-by: Greg Kroah-Hartman

pwm: sysfs: Replace sprintf() with sysfs_emit()

2022-09-28T15:52:02Z

While the uses in this code are unproblematic, it's generally safer for sysfs outputs to use the new sysfs_emit() helper instead of raw calls to sprintf() and friends. This also has the benefit of annotating the uses, which makes them easier to audit and potentially use them to generate sysfs documentation from them. This patch replaces existing sprintf() calls straightforwardly with the new helper. Signed-off-by: Andy Shevchenko Reviewed-by: Uwe Kleine-König Signed-off-by: Thierry Reding

pwm: sysfs: Switch to DEFINE_SIMPLE_DEV_PM_OPS() and pm_sleep_ptr()

2022-09-28T12:07:53Z

Using these newer macros allows the compiler to remove the unused structure and functions when !CONFIG_PM_SLEEP + removes the need to mark pm functions __maybe_unused. Signed-off-by: Andy Shevchenko Reviewed-by: Uwe Kleine-König Signed-off-by: Thierry Reding

pwm: Allow store 64-bit duty cycle from sysfs interface

2020-09-24T07:18:14Z

PWM core was converted to u64 by the commit a9d887dc1c60 ("pwm: Convert period and duty cycle to u64") but did not change the duty_cycle_store() so it will error out if trying to pass a numeric string bigger than 2^32-1. Fix this by using u64 and kstrtou64() in duty_cycle_store(). Signed-off-by: Jarkko Nikula Acked-by: Guru Das Srinagesh Acked-by: Uwe Kleine-König Signed-off-by: Thierry Reding

pwm: Convert period and duty cycle to u64

2020-06-17T18:42:11Z

Because period and duty cycle are defined as ints with units of nanoseconds, the maximum time duration that can be set is limited to ~2.147 seconds. Change their definitions to u64 in the structs of the PWM framework so that higher durations may be set. Also use the right format specifiers in debug prints in both core.c, pwm-stm32-lp.c as well as video/fbdev/ssd1307fb.c. Reported-by: kbuild test robot Signed-off-by: Guru Das Srinagesh Acked-by: Uwe Kleine-König Signed-off-by: Thierry Reding

Merge tag 'pwm/for-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm

2019-07-09T15:57:45Z

Pull pwm updates from Thierry Reding: "This set of changes contains a new driver for SiFive SoCs as well as enhancements to the core (device links are used to track dependencies between PWM providers and consumers, support for PWM controllers via ACPI, sysfs will now suspend/resume PWMs that it has claimed) and various existing drivers" * tag 'pwm/for-5.3-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/thierry.reding/linux-pwm: (37 commits) pwm: fsl-ftm: Make sure to unlock mutex on failure pwm: fsl-ftm: Use write protection for prescaler & polarity pwm: fsl-ftm: More relaxed permissions for updating period pwm: atmel-hlcdc: Add compatible for SAM9X60 HLCDC's PWM pwm: bcm2835: Improve precision of PWM leds: pwm: Support ACPI via firmware-node framework pwm: Add support referencing PWMs from ACPI pwm: rcar: Remove suspend/resume support pwm: sysfs: Add suspend/resume support pwm: Add power management descriptions pwm: meson: Add documentation to the driver pwm: meson: Add support PWM_POLARITY_INVERSED when disabling pwm: meson: Don't cache struct pwm_state internally pwm: meson: Read the full hardware state in meson_pwm_get_state() pwm: meson: Simplify the calculation of the pre-divider and count pwm: meson: Move pwm_set_chip_data() to meson_pwm_request() pwm: meson: Add the per-channel register offsets and bits in a struct pwm: meson: Add the meson_pwm_channel data to struct meson_pwm pwm: meson: Pass struct pwm_device to meson_pwm_calc() pwm: meson: Don't duplicate the polarity internally ...