| Message ID | 20231220145726.640627-9-fabrice.gasnier@foss.st.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | counter: Add stm32 timer events support | expand |
On Wed, Dec 20, 2023 at 03:57:24PM +0100, Fabrice Gasnier wrote: > 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. > > Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com> > --- > Changes in v3: > - New patch split from: > "counter: stm32-timer-cnt: populate capture channels and check encoder" > --- > drivers/counter/stm32-timer-cnt.c | 17 +++++++++++++++++ > 1 file changed, 17 insertions(+) > > diff --git a/drivers/counter/stm32-timer-cnt.c b/drivers/counter/stm32-timer-cnt.c > index 55eb6af34750..b5dc4378fecf 100644 > --- a/drivers/counter/stm32-timer-cnt.c > +++ b/drivers/counter/stm32-timer-cnt.c > @@ -43,6 +43,7 @@ struct stm32_timer_cnt { > struct stm32_timer_regs bak; > bool has_encoder; > u32 idx; > + unsigned int nchannels; > }; > > static const enum counter_function stm32_count_functions[] = { > @@ -417,6 +418,20 @@ static struct counter_count stm32_counts = { > .num_ext = ARRAY_SIZE(stm32_count_ext) > }; > > +static void stm32_timer_cnt_detect_channels(struct platform_device *pdev, Like stm32_timer_cnt_probe_encoder() in one of the previous patches, this function uses 'pdev' only to access 'dev'. Pass a reference to 'dev' directly instead. William Breathitt Gray
diff --git a/drivers/counter/stm32-timer-cnt.c b/drivers/counter/stm32-timer-cnt.c index 55eb6af34750..b5dc4378fecf 100644 --- a/drivers/counter/stm32-timer-cnt.c +++ b/drivers/counter/stm32-timer-cnt.c @@ -43,6 +43,7 @@ struct stm32_timer_cnt { struct stm32_timer_regs bak; bool has_encoder; u32 idx; + unsigned int nchannels; }; static const enum counter_function stm32_count_functions[] = { @@ -417,6 +418,20 @@ static struct counter_count stm32_counts = { .num_ext = ARRAY_SIZE(stm32_count_ext) }; +static void stm32_timer_cnt_detect_channels(struct platform_device *pdev, + struct stm32_timer_cnt *priv) +{ + u32 ccer, ccer_backup; + + regmap_read(priv->regmap, TIM_CCER, &ccer_backup); + regmap_set_bits(priv->regmap, TIM_CCER, TIM_CCER_CCXE); + regmap_read(priv->regmap, TIM_CCER, &ccer); + regmap_write(priv->regmap, TIM_CCER, ccer_backup); + priv->nchannels = hweight32(ccer & TIM_CCER_CCXE); + + dev_dbg(&pdev->dev, "has %d cc channels\n", priv->nchannels); +} + /* encoder supported on TIM1 TIM2 TIM3 TIM4 TIM5 TIM8 */ #define STM32_TIM_ENCODER_SUPPORTED (BIT(0) | BIT(1) | BIT(2) | BIT(3) | BIT(4) | BIT(7)) @@ -484,6 +499,8 @@ static int stm32_timer_cnt_probe(struct platform_device *pdev) if (ret) return ret; + stm32_timer_cnt_detect_channels(pdev, priv); + counter->name = dev_name(dev); counter->parent = dev; counter->ops = &stm32_timer_cnt_ops;
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. Signed-off-by: Fabrice Gasnier <fabrice.gasnier@foss.st.com> --- Changes in v3: - New patch split from: "counter: stm32-timer-cnt: populate capture channels and check encoder" --- drivers/counter/stm32-timer-cnt.c | 17 +++++++++++++++++ 1 file changed, 17 insertions(+)