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counter: stm32-timer-cnt: introduce clock signal

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Introduce the internal clock signal, used to count when in simple rising
function. Also add the "frequency" extension to the clock signal.

With this patch, signal action reports a consistent state when "increase"
function is used, and the counting frequency:
    $ echo increase > function
    $ grep -H "" signal*_action
    signal0_action:none
    signal1_action:none
    signal2_action:rising edge
    $ echo 1 > enable
    $ cat count
    25425
    $ cat count
    44439
    $ cat ../signal2/frequency
    208877930

Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com>
Link: https://lore.kernel.org/r/20240307133306.383045-5-fabrice.gasnier@foss.st.com
Signed-off-by: William Breathitt Gray <william.gray@linaro.org>
This commit is contained in:
Fabrice Gasnier 2024-03-07 14:33:00 +01:00 committed by William Breathitt Gray
parent 5679d5f76c
commit 7a6c69f2be
1 changed files with 49 additions and 4 deletions
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53
drivers/counter/stm32-timer-cnt.c
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@ -23,6 +23,7 @@
#define STM32_CH1_SIG 0
#define STM32_CH2_SIG 1
#define STM32_CLOCK_SIG 2
struct stm32_timer_regs {
u32 cr1;
@ -226,6 +227,10 @@ static struct counter_comp stm32_count_ext[] = {
stm32_count_ceiling_write),
};
static const enum counter_synapse_action stm32_clock_synapse_actions[] = {
COUNTER_SYNAPSE_ACTION_RISING_EDGE,
};
static const enum counter_synapse_action stm32_synapse_actions[] = {
COUNTER_SYNAPSE_ACTION_NONE,
COUNTER_SYNAPSE_ACTION_BOTH_EDGES
@ -246,7 +251,10 @@ static int stm32_action_read(struct counter_device *counter,
switch (function) {
case COUNTER_FUNCTION_INCREASE:
/* counts on internal clock when CEN=1 */
*action = COUNTER_SYNAPSE_ACTION_NONE;
if (synapse->signal->id == STM32_CLOCK_SIG)
*action = COUNTER_SYNAPSE_ACTION_RISING_EDGE;
else
*action = COUNTER_SYNAPSE_ACTION_NONE;
return 0;
case COUNTER_FUNCTION_QUADRATURE_X2_A:
/* counts up/down on TI1FP1 edge depending on TI2FP2 level */
@ -264,7 +272,10 @@ static int stm32_action_read(struct counter_device *counter,
return 0;
case COUNTER_FUNCTION_QUADRATURE_X4:
/* counts up/down on both TI1FP1 and TI2FP2 edges */
*action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
if (synapse->signal->id == STM32_CH1_SIG || synapse->signal->id == STM32_CH2_SIG)
*action = COUNTER_SYNAPSE_ACTION_BOTH_EDGES;
else
*action = COUNTER_SYNAPSE_ACTION_NONE;
return 0;
default:
return -EINVAL;
@ -279,7 +290,30 @@ static const struct counter_ops stm32_timer_cnt_ops = {
.action_read = stm32_action_read,
};
static int stm32_count_clk_get_freq(struct counter_device *counter,
struct counter_signal *signal, u64 *freq)
{
struct stm32_timer_cnt *const priv = counter_priv(counter);
*freq = clk_get_rate(priv->clk);
return 0;
}
static struct counter_comp stm32_count_clock_ext[] = {
COUNTER_COMP_FREQUENCY(stm32_count_clk_get_freq),
};
static struct counter_signal stm32_signals[] = {
/*
* Need to declare all the signals as a static array, and keep the signals order here,
* even if they're unused or unexisting on some timer instances. It's an abstraction,
* e.g. high level view of the counter features.
*
* Userspace programs may rely on signal0 to be "Channel 1", signal1 to be "Channel 2",
* and so on. When a signal is unexisting, the COUNTER_SYNAPSE_ACTION_NONE can be used,
* to indicate that a signal doesn't affect the counter.
*/
{
.id = STM32_CH1_SIG,
.name = "Channel 1"
@ -287,7 +321,13 @@ static struct counter_signal stm32_signals[] = {
{
.id = STM32_CH2_SIG,
.name = "Channel 2"
}
},
{
.id = STM32_CLOCK_SIG,
.name = "Clock",
.ext = stm32_count_clock_ext,
.num_ext = ARRAY_SIZE(stm32_count_clock_ext),
},
};
static struct counter_synapse stm32_count_synapses[] = {
@ -300,7 +340,12 @@ static struct counter_synapse stm32_count_synapses[] = {
.actions_list = stm32_synapse_actions,
.num_actions = ARRAY_SIZE(stm32_synapse_actions),
.signal = &stm32_signals[STM32_CH2_SIG]
}
},
{
.actions_list = stm32_clock_synapse_actions,
.num_actions = ARRAY_SIZE(stm32_clock_synapse_actions),
.signal = &stm32_signals[STM32_CLOCK_SIG]
},
};
static struct counter_count stm32_counts = {