clk: pwm: Convert to platform remove callback returning void

The .remove() callback for a platform driver returns an int which makes
many driver authors wrongly assume it's possible to do error handling by
returning an error code. However the value returned is (mostly) ignored
and this typically results in resource leaks. To improve here there is a
quest to make the remove callback return void. In the first step of this
quest all drivers are converted to .remove_new() which already returns
void.

Trivially convert this driver from always returning zero in the remove
callback to the void returning variant.

Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20230312161512.2715500-14-u.kleine-koenig@pengutronix.de
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: pwm: drop of_match_ptr from of_device_id table

The driver can match only via the DT table so the table should be always
used and the of_match_ptr does not have any sense (this also allows ACPI
matching via PRP0001, even though it might be not relevant here). This
fixes compile warning (!CONFIG_OF && !CONFIG_MODULES):

drivers/clk/clk-pwm.c:139:34: warning:
‘clk_pwm_dt_ids’ defined but not used [-Wunused-const-variable=]

Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Link: https://lore.kernel.org/r/20201103162435.13689-1-krzk@kernel.org
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: pwm: Use 64-bit division function

Since the PWM framework is switching struct pwm_args.period's datatype
to u64, prepare for this transition by using div64_u64() to handle a
64-bit divisor.

Also ensure that divide-by-zero (with fixed_rate as denominator) does
not happen with an explicit check with probe failure as a consequence.

Signed-off-by: Guru Das Srinagesh <gurus@codeaurora.org>
Acked-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 500

Based on 2 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-only

has been chosen to replace the boilerplate/reference in 4122 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

clk: pwm: implement the .get_duty_cycle callback

Commit 9fba738a53dda2 ("clk: add duty cycle support") added support for
getting and setting the duty cycle of a clock. This implements the
get_duty_cycle callback for PWM based clocks so the duty cycle is shown
in the debugfs output (/sys/kernel/debug/clk/clk_summary).

Signed-off-by: Martin Blumenstingl <martin.blumenstingl@googlemail.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: Remove CLK_IS_BASIC clk flag

This flag was historically used to indicate that a clk is a "basic" type
of clk like a mux, divider, gate, etc. This never turned out to be very
useful though because it was hard to cleanly split "basic" clks from
other clks in a system. This one flag was a way for type introspection
and it just didn't scale. If anything, it was used by the TI clk driver
to indicate that a clk_hw wasn't contained in the SoC specific clk
structure. We can get rid of this define now that TI is finding those
clks a different way.

Cc: Tero Kristo <t-kristo@ti.com>
Cc: Ralf Baechle <ralf@linux-mips.org>
Cc: Paul Burton <paul.burton@mips.com>
Cc: James Hogan <jhogan@kernel.org>
Cc: <linux-mips@vger.kernel.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Kevin Hilman <khilman@baylibre.com>
Cc: <linux-pwm@vger.kernel.org>
Cc: <linux-amlogic@lists.infradead.org>
Acked-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>

clk: pwm: Migrate to clk_hw based OF and registration APIs

Now that we have clk_hw based provider APIs to register clks, we
can get rid of struct clk pointers while registering clks in
these drivers, allowing us to move closer to a clear split of
consumer and provider clk APIs.

Cc: Janusz Uzycki <j.uzycki@elproma.com.pl>
Cc: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: pwm: Use pwm_get_args() where appropriate

The PWM framework has clarified the concept of reference PWM config (the
platform dependent config retrieved from the DT or the PWM lookup table)
and real PWM state.

Use pwm_get_args() when the PWM user wants to retrieve this reference
config and not the current state.

This is part of the rework allowing the PWM framework to support
hardware readout and expose real PWM state even when the PWM has just
been requested (before the user calls pwm_config/enable/disable()).

Signed-off-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Acked-by: Stephen Boyd <sboyd@codeaurora.org>
Signed-off-by: Thierry Reding <thierry.reding@gmail.com>

clk: pwm: Remove CLK_IS_ROOT

This flag is a no-op now. Remove usage of the flag.

Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>

clk: Add PWM clock driver

Some board designers, when running out of clock output pads, decide to
(mis)use PWM output pads to provide a clock to external components.
This driver supports this practice by providing an adapter between the
PWM and clock bindings in the device tree. As the PWM bindings specify
the period in the device tree, this is a fixed clock.

Tested-by: Janusz Uzycki <j.uzycki@elproma.com.pl>
Signed-off-by: Philipp Zabel <p.zabel@pengutronix.de>
Signed-off-by: Michael Turquette <mturquette@linaro.org>