linux.git/drivers/clk/stm32, branch v6.7

clk: stm32: Fix a signedness issue in clk_stm32_composite_determine_rate()

2023-10-13T00:30:54+00:00

The divider_ro_round_rate() function could potentially return -EINVAL on
error but the error handling doesn't work because "rate" is unsigned.
It should be a type long.

Fixes: 06ed0fc0fbac ("clk: stm32: composite: Switch to determine_rate")
Signed-off-by: Dan Carpenter 
Link: https://lore.kernel.org/r/d9a78453-9b40-48c1-830e-00751ba3ecb8@kili.mountain
Acked-by: Maxime Ripard 
Signed-off-by: Stephen Boyd

clk: stm32: composite: Switch to determine_rate

2023-06-09T01:39:35+00:00

The STM32 composite clocks implements a mux with a set_parent hook, but
doesn't provide a determine_rate implementation.

This is a bit odd, since set_parent() is there to, as its name implies,
change the parent of a clock. However, the most likely candidate to
trigger that parent change is a call to clk_set_rate(), with
determine_rate() figuring out which parent is the best suited for a
given rate.

The other trigger would be a call to clk_set_parent(), but it's far less
used, and it doesn't look like there's any obvious user for that clock.

So, the set_parent hook is effectively unused, possibly because of an
oversight. However, it could also be an explicit decision by the
original author to avoid any reparenting but through an explicit call to
clk_set_parent().

The driver does implement round_rate() though, which means that we can
change the rate of the clock, but we will never get to change the
parent.

However, It's hard to tell whether it's been done on purpose or not.

Since we'll start mandating a determine_rate() implementation, let's
convert the round_rate() implementation to a determine_rate(), which
will also make the current behavior explicit. And if it was an
oversight, the clock behaviour can be adjusted later on.

Cc: Alexandre Torgue 
Cc: Maxime Coquelin 
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-stm32@st-md-mailman.stormreply.com
Signed-off-by: Maxime Ripard 
Link: https://lore.kernel.org/r/20221018-clk-range-checks-fixes-v4-63-971d5077e7d2@cerno.tech
Signed-off-by: Stephen Boyd

clk: stm32: core: Add a determine_rate hook

2023-06-09T01:39:30+00:00

The STM32 mux clock implements a mux with a set_parent hook, but
doesn't provide a determine_rate implementation.

This is a bit odd, since set_parent() is there to, as its name implies,
change the parent of a clock. However, the most likely candidate to
trigger that parent change is a call to clk_set_rate(), with
determine_rate() figuring out which parent is the best suited for a
given rate.

The other trigger would be a call to clk_set_parent(), but it's far less
used, and it doesn't look like there's any obvious user for that clock.

So, the set_parent hook is effectively unused, possibly because of an
oversight. However, it could also be an explicit decision by the
original author to avoid any reparenting but through an explicit call to
clk_set_parent().

The latter case would be equivalent to setting the flag
CLK_SET_RATE_NO_REPARENT, together with setting our determine_rate hook
to __clk_mux_determine_rate(). Indeed, if no determine_rate
implementation is provided, clk_round_rate() (through
clk_core_round_rate_nolock()) will call itself on the parent if
CLK_SET_RATE_PARENT is set, and will not change the clock rate
otherwise.

And if it was an oversight, then we are at least explicit about our
behavior now and it can be further refined down the line.

Since the CLK_SET_RATE_NO_REPARENT flag was already set though, it seems
unlikely.

Cc: Alexandre Torgue 
Cc: Maxime Coquelin 
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-stm32@st-md-mailman.stormreply.com
Signed-off-by: Maxime Ripard 
Link: https://lore.kernel.org/r/20221018-clk-range-checks-fixes-v4-33-971d5077e7d2@cerno.tech
Signed-off-by: Stephen Boyd

clk: stm32: Convert to platform remove callback returning void

2023-03-29T02:31:44+00:00

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 
Link: https://lore.kernel.org/r/20230312161512.2715500-26-u.kleine-koenig@pengutronix.de
Signed-off-by: Stephen Boyd

clk: stm32: rcc_reset: Fix missing spin_lock_init()

2022-06-09T22:34:08+00:00

The driver allocates the spinlock but not initialize it.
Use spin_lock_init() on it to initialize it correctly.

Fixes: 637cee5ffc71 ("clk: stm32: Introduce STM32MP13 RCC drivers (Reset Clock Controller)")
Reported-by: Hulk Robot 
Signed-off-by: Wei Yongjun 
Link: https://lore.kernel.org/r/20220608021154.990347-1-weiyongjun1@huawei.com
Tested-by: Gabriel Fernandez 
Reviewed-by: Gabriel Fernandez 
Signed-off-by: Stephen Boyd

clk: stm32mp13: add safe mux management

2022-05-21T04:07:49+00:00

Some muxes need to set a the safe position when clock is off.

Signed-off-by: Gabriel Fernandez 
Link: https://lore.kernel.org/r/20220516070600.7692-12-gabriel.fernandez@foss.st.com
Signed-off-by: Stephen Boyd

clk: stm32mp13: add multi mux function

2022-05-21T04:07:49+00:00

Some RCC muxes can manages two output clocks with same register.

Signed-off-by: Gabriel Fernandez 
Link: https://lore.kernel.org/r/20220516070600.7692-11-gabriel.fernandez@foss.st.com
Signed-off-by: Stephen Boyd

clk: stm32mp13: add all STM32MP13 kernel clocks

2022-05-21T04:07:49+00:00

Complete all kernel clocks of stm32mp13.

Signed-off-by: Gabriel Fernandez 
Link: https://lore.kernel.org/r/20220516070600.7692-10-gabriel.fernandez@foss.st.com
Signed-off-by: Stephen Boyd

clk: stm32mp13: add all STM32MP13 peripheral clocks

2022-05-21T04:07:49+00:00

All peripheral clocks are mainly based on stm32_gate clock.

Signed-off-by: Gabriel Fernandez 
Link: https://lore.kernel.org/r/20220516070600.7692-9-gabriel.fernandez@foss.st.com
Signed-off-by: Stephen Boyd

clk: stm32mp13: manage secured clocks

2022-05-21T04:07:49+00:00

Don't register a clock if this clock is secured.

Signed-off-by: Gabriel Fernandez 
Link: https://lore.kernel.org/r/20220516070600.7692-8-gabriel.fernandez@foss.st.com
Signed-off-by: Stephen Boyd