counter: stm32-timer-cnt: introduce channels

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 <william.gray@linaro.org>
Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Link: https://lore.kernel.org/r/20240307133306.383045-8-fabrice.gasnier@foss.st.com


Signed-off-by: William Breathitt Gray <william.gray@linaro.org>

drivers/counter/stm32-timer-cnt.c

@@ -25,6 +25,8 @@
 #define STM32_CH1_SIG		0
 #define STM32_CH2_SIG		1
 #define STM32_CLOCK_SIG		2
+#define STM32_CH3_SIG		3
+#define STM32_CH4_SIG		4
 
 struct stm32_timer_regs {
 	u32 cr1;
@@ -365,6 +367,14 @@ static struct counter_signal stm32_signals[] = {
 		.ext = stm32_count_clock_ext,
 		.num_ext = ARRAY_SIZE(stm32_count_clock_ext),
 	},
+	{
+		.id = STM32_CH3_SIG,
+		.name = "Channel 3"
+	},
+	{
+		.id = STM32_CH4_SIG,
+		.name = "Channel 4"
+	},
 };
 
 static struct counter_synapse stm32_count_synapses[] = {
@@ -383,6 +393,16 @@ static struct counter_synapse stm32_count_synapses[] = {
 		.num_actions = ARRAY_SIZE(stm32_clock_synapse_actions),
 		.signal = &stm32_signals[STM32_CLOCK_SIG]
 	},
+	{
+		.actions_list = stm32_synapse_actions,
+		.num_actions = ARRAY_SIZE(stm32_synapse_actions),
+		.signal = &stm32_signals[STM32_CH3_SIG]
+	},
+	{
+		.actions_list = stm32_synapse_actions,
+		.num_actions = ARRAY_SIZE(stm32_synapse_actions),
+		.signal = &stm32_signals[STM32_CH4_SIG]
+	},
 };
 
 static struct counter_count stm32_counts = {