linux-toradex.git/drivers/counter/stm32-timer-cnt.c, branch v7.1

counter: stm32-timer-cnt: add support for stm32mp25

2025-05-15T00:20:12+00:00

Add support for STM32MP25 SoC. There are new counter modes that may be
implemented in later. Still, use newly introduced compatible to handle
this new HW variant and avoid being blocked with existing compatible
in SoC dtsi file. Modes supported currently still remains compatible.
New timer 20 has encoder capability, add it to the list.

Signed-off-by: Fabrice Gasnier 
Link: https://lore.kernel.org/r/20250110091922.980627-4-fabrice.gasnier@foss.st.com
Signed-off-by: William Breathitt Gray

module: Convert symbol namespace to string literal

2024-12-02T19:34:44+00:00

Clean up the existing export namespace code along the same lines of
commit 33def8498fdd ("treewide: Convert macro and uses of __section(foo)
to __section("foo")") and for the same reason, it is not desired for the
namespace argument to be a macro expansion itself.

Scripted using

  git grep -l -e MODULE_IMPORT_NS -e EXPORT_SYMBOL_NS | while read file;
  do
    awk -i inplace '
      /^#define EXPORT_SYMBOL_NS/ {
        gsub(/__stringify\(ns\)/, "ns");
        print;
        next;
      }
      /^#define MODULE_IMPORT_NS/ {
        gsub(/__stringify\(ns\)/, "ns");
        print;
        next;
      }
      /MODULE_IMPORT_NS/ {
        $0 = gensub(/MODULE_IMPORT_NS\(([^)]*)\)/, "MODULE_IMPORT_NS(\"\\1\")", "g");
      }
      /EXPORT_SYMBOL_NS/ {
        if ($0 ~ /(EXPORT_SYMBOL_NS[^(]*)\(([^,]+),/) {
  	if ($0 !~ /(EXPORT_SYMBOL_NS[^(]*)\(([^,]+), ([^)]+)\)/ &&
  	    $0 !~ /(EXPORT_SYMBOL_NS[^(]*)\(\)/ &&
  	    $0 !~ /^my/) {
  	  getline line;
  	  gsub(/[[:space:]]*\\$/, "");
  	  gsub(/[[:space:]]/, "", line);
  	  $0 = $0 " " line;
  	}

  	$0 = gensub(/(EXPORT_SYMBOL_NS[^(]*)\(([^,]+), ([^)]+)\)/,
  		    "\\1(\\2, \"\\3\")", "g");
        }
      }
      { print }' $file;
  done

Requested-by: Masahiro Yamada 
Signed-off-by: Peter Zijlstra (Intel) 
Link: https://mail.google.com/mail/u/2/#inbox/FMfcgzQXKWgMmjdFwwdsfgxzKpVHWPlc
Acked-by: Greg KH 
Signed-off-by: Linus Torvalds

counter: stm32-timer-cnt: Add check for clk_enable()

2024-11-05T00:15:20+00:00

Add check for the return value of clk_enable() in order to catch the
potential exception.

Fixes: c5b8425514da ("counter: stm32-timer-cnt: add power management support")
Fixes: ad29937e206f ("counter: Add STM32 Timer quadrature encoder")
Signed-off-by: Jiasheng Jiang 
Link: https://lore.kernel.org/r/20241104191825.40155-1-jiashengjiangcool@gmail.com
Signed-off-by: William Breathitt Gray

counter: stm32-timer-cnt: fix device_node handling in probe_encoder()

2024-11-01T04:46:54+00:00

Device nodes accessed via of_get_compatible_child() require
of_node_put() to be called when the node is no longer required to avoid
leaving a reference to the node behind, leaking the resource.

In this case, the usage of 'tnode' is straightforward and there are no
error paths, allowing for a single of_node_put() when 'tnode' is no
longer required.

Cc: stable@vger.kernel.org
Fixes: 29646ee33cc3 ("counter: stm32-timer-cnt: add checks on quadrature encoder capability")
Signed-off-by: Javier Carrasco 
Link: https://lore.kernel.org/r/20241027-stm32-timer-cnt-of_node_put-v1-1-ebd903cdf7ac@gmail.com
Signed-off-by: William Breathitt Gray

counter: stm32-timer-cnt: Use TIM_DIER_CCxIE(x) instead of TIM_DIER_CCxIE(x)

2024-06-26T15:09:55+00:00

These two defines have the same purpose and this change doesn't
introduce any differences in drivers/counter/stm32-timer-cnt.o.

The only difference between the two is that

	TIM_DIER_CC_IE(1) == TIM_DIER_CC2IE

while

	TIM_DIER_CCxIE(1) == TIM_DIER_CC1IE

. That makes it necessary to have an explicit "+ 1" in the user code,
but IMHO this is a good thing as this is the code locatation that
"knows" that for software channel 1 you have to use TIM_DIER_CC2IE
(because software guys start counting at 0, while the relevant hardware
designer started at 1).

Signed-off-by: Uwe Kleine-König 
Acked-by: William Breathitt Gray 
Link: https://lore.kernel.org/r/126bd153a03f39e42645573eecf44ffab5354fc7.1718791090.git.u.kleine-koenig@baylibre.com
Signed-off-by: Lee Jones

counter: stm32-timer-cnt: add support for capture events

2024-04-02T17:10:34+00:00

Add support for capture events. Captured counter value for each channel
can be retrieved through CCRx register.
STM32 timers can have up to 4 capture channels (on input channel 1 to
channel 4), hence need to check the number of channels before reading
the capture data.
The capture configuration is hard-coded to capture signals on both edges
(non-inverted). Interrupts are used to report events independently for
each channel.

Reviewed-by: William Breathitt Gray 
Acked-by: Lee Jones 
Signed-off-by: Fabrice Gasnier 
Link: https://lore.kernel.org/r/20240307133306.383045-11-fabrice.gasnier@foss.st.com
Signed-off-by: William Breathitt Gray

counter: stm32-timer-cnt: add support for overflow events

2024-04-02T17:10:34+00:00

Add support overflow events. Also add the related validation and
configuration routine. Register and enable interrupts to push events.
STM32 Timers can have either 1 global interrupt, or 4 dedicated interrupt
lines. Request only the necessary interrupt, e.g. either global interrupt
that can report all event types, or update interrupt only for overflow
event.

Reviewed-by: William Breathitt Gray 
Signed-off-by: Fabrice Gasnier 
Link: https://lore.kernel.org/r/20240307133306.383045-10-fabrice.gasnier@foss.st.com
Signed-off-by: William Breathitt Gray

counter: stm32-timer-cnt: probe number of channels from registers

2024-04-02T17:10:34+00:00

Probe the number of capture compare channels, by writing CCER register bits
and read them back. Take care to restore the register original value.

This is a precursor patch to support capture channels.

Reviewed-by: William Breathitt Gray 
Signed-off-by: Fabrice Gasnier 
Link: https://lore.kernel.org/r/20240307133306.383045-9-fabrice.gasnier@foss.st.com
Signed-off-by: William Breathitt Gray

counter: stm32-timer-cnt: introduce channels

2024-04-02T17:10:34+00:00

Simply add channels 3 and 4 that can be used for capture. Statically
add them, despite some timers doesn't have them. Rather rely on
stm32_action_read that will report "none" action for these currently.

Reviewed-by: William Breathitt Gray 
Signed-off-by: Fabrice Gasnier 
Link: https://lore.kernel.org/r/20240307133306.383045-8-fabrice.gasnier@foss.st.com
Signed-off-by: William Breathitt Gray

counter: stm32-timer-cnt: add checks on quadrature encoder capability

2024-04-02T17:10:34+00:00

This is a precursor patch to support capture channels on all possible
channels and stm32 timer types. Original driver was intended to be used
only as quadrature encoder and simple counter on internal clock.

So, add a check on encoder capability, so the driver may be probed for
timer instances without encoder feature. This way, all timers may be used
as simple counter on internal clock, starting from here.

Encoder capability is retrieved by using the timer index (originally in
stm32-timer-trigger driver and dt-bindings). The need to keep backward
compatibility with existing device tree lead to parse aside trigger node.

Reviewed-by: William Breathitt Gray 
Signed-off-by: Fabrice Gasnier 
Link: https://lore.kernel.org/r/20240307133306.383045-7-fabrice.gasnier@foss.st.com
Signed-off-by: William Breathitt Gray