[PATCH] iio: stm32 trigger: Add support for TRGO2 triggers

Benjamin Gaignard benjamin.gaignard at linaro.org
Wed Apr 26 04:55:39 EDT 2017


2017-04-26 10:17 GMT+02:00 Fabrice Gasnier <fabrice.gasnier at st.com>:
> Add support for TRGO2 trigger that can be found on STM32F7.
> Add additional master modes supported by TRGO2.
> Register additional "tim[1/8]_trgo2" triggers for timer1 & timer8.
> Detect TRGO2 timer capability (master mode selection 2).
>
> Signed-off-by: Fabrice Gasnier <fabrice.gasnier at st.com>
> ---
>  .../ABI/testing/sysfs-bus-iio-timer-stm32          |  15 +++
>  drivers/iio/trigger/stm32-timer-trigger.c          | 113 ++++++++++++++++++---
>  include/linux/iio/timer/stm32-timer-trigger.h      |   2 +
>  include/linux/mfd/stm32-timers.h                   |   2 +
>  4 files changed, 118 insertions(+), 14 deletions(-)
>
> diff --git a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32 b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
> index 230020e..47647b4 100644
> --- a/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
> +++ b/Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
> @@ -16,6 +16,21 @@ Description:
>                 - "OC2REF"    : OC2REF signal is used as trigger output.
>                 - "OC3REF"    : OC3REF signal is used as trigger output.
>                 - "OC4REF"    : OC4REF signal is used as trigger output.
> +               Additional modes (on TRGO2 only):
> +               - "OC5REF"    : OC5REF signal is used as trigger output.
> +               - "OC6REF"    : OC6REF signal is used as trigger output.
> +               - "compare_pulse_OC4REF":
> +                 OC4REF rising or falling edges generate pulses.
> +               - "compare_pulse_OC6REF":
> +                 OC6REF rising or falling edges generate pulses.
> +               - "compare_pulse_OC4REF_r_or_OC6REF_r":
> +                 OC4REF or OC6REF rising edges generate pulses.
> +               - "compare_pulse_OC4REF_r_or_OC6REF_f":
> +                 OC4REF rising or OC6REF falling edges generate pulses.
> +               - "compare_pulse_OC5REF_r_or_OC6REF_r":
> +                 OC5REF or OC6REF rising edges generate pulses.
> +               - "compare_pulse_OC5REF_r_or_OC6REF_f":
> +                 OC5REF rising or OC6REF falling edges generate pulses.
>
>  What:          /sys/bus/iio/devices/triggerX/master_mode
>  KernelVersion: 4.11
> diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c
> index 0f1a2cf..a0031b7 100644
> --- a/drivers/iio/trigger/stm32-timer-trigger.c
> +++ b/drivers/iio/trigger/stm32-timer-trigger.c
> @@ -14,19 +14,19 @@
>  #include <linux/module.h>
>  #include <linux/platform_device.h>
>
> -#define MAX_TRIGGERS 6
> +#define MAX_TRIGGERS 7
>  #define MAX_VALIDS 5
>
>  /* List the triggers created by each timer */
>  static const void *triggers_table[][MAX_TRIGGERS] = {
> -       { TIM1_TRGO, TIM1_CH1, TIM1_CH2, TIM1_CH3, TIM1_CH4,},
> +       { TIM1_TRGO, TIM1_TRGO2, TIM1_CH1, TIM1_CH2, TIM1_CH3, TIM1_CH4,},
>         { TIM2_TRGO, TIM2_CH1, TIM2_CH2, TIM2_CH3, TIM2_CH4,},
>         { TIM3_TRGO, TIM3_CH1, TIM3_CH2, TIM3_CH3, TIM3_CH4,},
>         { TIM4_TRGO, TIM4_CH1, TIM4_CH2, TIM4_CH3, TIM4_CH4,},
>         { TIM5_TRGO, TIM5_CH1, TIM5_CH2, TIM5_CH3, TIM5_CH4,},
>         { TIM6_TRGO,},
>         { TIM7_TRGO,},
> -       { TIM8_TRGO, TIM8_CH1, TIM8_CH2, TIM8_CH3, TIM8_CH4,},
> +       { TIM8_TRGO, TIM8_TRGO2, TIM8_CH1, TIM8_CH2, TIM8_CH3, TIM8_CH4,},
>         { TIM9_TRGO, TIM9_CH1, TIM9_CH2,},
>         { }, /* timer 10 */
>         { }, /* timer 11 */
> @@ -56,9 +56,16 @@ struct stm32_timer_trigger {
>         u32 max_arr;
>         const void *triggers;
>         const void *valids;
> +       bool has_trgo2;
>  };
>
> +static bool stm32_timer_is_trgo2_name(const char *name)
> +{
> +       return !!strstr(name, "trgo2");
> +}
> +
>  static int stm32_timer_start(struct stm32_timer_trigger *priv,
> +                            struct iio_trigger *trig,
>                              unsigned int frequency)
>  {
>         unsigned long long prd, div;
> @@ -102,7 +109,12 @@ static int stm32_timer_start(struct stm32_timer_trigger *priv,
>         regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, TIM_CR1_ARPE);
>
>         /* Force master mode to update mode */
> -       regmap_update_bits(priv->regmap, TIM_CR2, TIM_CR2_MMS, 0x20);
> +       if (stm32_timer_is_trgo2_name(trig->name))
> +               regmap_update_bits(priv->regmap, TIM_CR2, TIM_CR2_MMS2,
> +                                  0x2 << TIM_CR2_MMS2_SHIFT);
> +       else
> +               regmap_update_bits(priv->regmap, TIM_CR2, TIM_CR2_MMS,
> +                                  0x2 << TIM_CR2_MMS_SHIFT);
>
>         /* Make sure that registers are updated */
>         regmap_update_bits(priv->regmap, TIM_EGR, TIM_EGR_UG, TIM_EGR_UG);
> @@ -150,7 +162,7 @@ static ssize_t stm32_tt_store_frequency(struct device *dev,
>         if (freq == 0) {
>                 stm32_timer_stop(priv);
>         } else {
> -               ret = stm32_timer_start(priv, freq);
> +               ret = stm32_timer_start(priv, trig, freq);
>                 if (ret)
>                         return ret;
>         }
> @@ -183,6 +195,9 @@ static IIO_DEV_ATTR_SAMP_FREQ(0660,
>                               stm32_tt_read_frequency,
>                               stm32_tt_store_frequency);
>
> +#define MASTER_MODE_MAX                7
> +#define MASTER_MODE2_MAX       15
> +
>  static char *master_mode_table[] = {
>         "reset",
>         "enable",
> @@ -191,7 +206,16 @@ static IIO_DEV_ATTR_SAMP_FREQ(0660,
>         "OC1REF",
>         "OC2REF",
>         "OC3REF",
> -       "OC4REF"
> +       "OC4REF",
> +       /* Master mode selection 2 only */
> +       "OC5REF",
> +       "OC6REF",
> +       "compare_pulse_OC4REF",
> +       "compare_pulse_OC6REF",
> +       "compare_pulse_OC4REF_r_or_OC6REF_r",
> +       "compare_pulse_OC4REF_r_or_OC6REF_f",
> +       "compare_pulse_OC5REF_r_or_OC6REF_r",
> +       "compare_pulse_OC5REF_r_or_OC6REF_f",
>  };
>
>  static ssize_t stm32_tt_show_master_mode(struct device *dev,
> @@ -199,10 +223,15 @@ static ssize_t stm32_tt_show_master_mode(struct device *dev,
>                                          char *buf)
>  {
>         struct stm32_timer_trigger *priv = dev_get_drvdata(dev);
> +       struct iio_trigger *trig = to_iio_trigger(dev);
>         u32 cr2;
>
>         regmap_read(priv->regmap, TIM_CR2, &cr2);
> -       cr2 = (cr2 & TIM_CR2_MMS) >> TIM_CR2_MMS_SHIFT;
> +
> +       if (stm32_timer_is_trgo2_name(trig->name))
> +               cr2 = (cr2 & TIM_CR2_MMS2) >> TIM_CR2_MMS2_SHIFT;
> +       else
> +               cr2 = (cr2 & TIM_CR2_MMS) >> TIM_CR2_MMS_SHIFT;
>
>         return snprintf(buf, PAGE_SIZE, "%s\n", master_mode_table[cr2]);
>  }
> @@ -212,13 +241,25 @@ static ssize_t stm32_tt_store_master_mode(struct device *dev,
>                                           const char *buf, size_t len)
>  {
>         struct stm32_timer_trigger *priv = dev_get_drvdata(dev);
> +       struct iio_trigger *trig = to_iio_trigger(dev);
> +       u32 mask, shift, master_mode_max;
>         int i;
>
> -       for (i = 0; i < ARRAY_SIZE(master_mode_table); i++) {
> +       if (stm32_timer_is_trgo2_name(trig->name)) {
> +               mask = TIM_CR2_MMS2;
> +               shift = TIM_CR2_MMS2_SHIFT;
> +               master_mode_max = MASTER_MODE2_MAX;
> +       } else {
> +               mask = TIM_CR2_MMS;
> +               shift = TIM_CR2_MMS_SHIFT;
> +               master_mode_max = MASTER_MODE_MAX;
> +       }
> +
> +       for (i = 0; i <= master_mode_max; i++) {
>                 if (!strncmp(master_mode_table[i], buf,
>                              strlen(master_mode_table[i]))) {
> -                       regmap_update_bits(priv->regmap, TIM_CR2,
> -                                          TIM_CR2_MMS, i << TIM_CR2_MMS_SHIFT);
> +                       regmap_update_bits(priv->regmap, TIM_CR2, mask,
> +                                          i << shift);
>                         /* Make sure that registers are updated */
>                         regmap_update_bits(priv->regmap, TIM_EGR,
>                                            TIM_EGR_UG, TIM_EGR_UG);
> @@ -229,8 +270,31 @@ static ssize_t stm32_tt_store_master_mode(struct device *dev,
>         return -EINVAL;
>  }
>
> -static IIO_CONST_ATTR(master_mode_available,
> -       "reset enable update compare_pulse OC1REF OC2REF OC3REF OC4REF");
> +static ssize_t stm32_tt_show_master_mode_avail(struct device *dev,
> +                                              struct device_attribute *attr,
> +                                              char *buf)
> +{
> +       struct iio_trigger *trig = to_iio_trigger(dev);
> +       unsigned int i, master_mode_max;
> +       size_t len = 0;
> +
> +       if (stm32_timer_is_trgo2_name(trig->name))
> +               master_mode_max = MASTER_MODE2_MAX;
> +       else
> +               master_mode_max = MASTER_MODE_MAX;
> +
> +       for (i = 0; i <= master_mode_max; i++)
> +               len += scnprintf(buf + len, PAGE_SIZE - len,
> +                       "%s ", master_mode_table[i]);
> +
> +       /* replace trailing space by newline */
> +       buf[len - 1] = '\n';
> +
> +       return len;
> +}
> +
> +static IIO_DEVICE_ATTR(master_mode_available, 0444,
> +                      stm32_tt_show_master_mode_avail, NULL, 0);
>
>  static IIO_DEVICE_ATTR(master_mode, 0660,
>                        stm32_tt_show_master_mode,
> @@ -240,7 +304,7 @@ static IIO_DEVICE_ATTR(master_mode, 0660,
>  static struct attribute *stm32_trigger_attrs[] = {
>         &iio_dev_attr_sampling_frequency.dev_attr.attr,
>         &iio_dev_attr_master_mode.dev_attr.attr,
> -       &iio_const_attr_master_mode_available.dev_attr.attr,
> +       &iio_dev_attr_master_mode_available.dev_attr.attr,
>         NULL,
>  };
>
> @@ -264,6 +328,12 @@ static int stm32_setup_iio_triggers(struct stm32_timer_trigger *priv)
>
>         while (cur && *cur) {
>                 struct iio_trigger *trig;
> +               bool cur_is_trgo2 = stm32_timer_is_trgo2_name(*cur);
> +
> +               if (cur_is_trgo2 && !priv->has_trgo2) {
> +                       cur++;
> +                       continue;
> +               }
>
>                 trig = devm_iio_trigger_alloc(priv->dev, "%s", *cur);
>                 if  (!trig)
> @@ -277,7 +347,7 @@ static int stm32_setup_iio_triggers(struct stm32_timer_trigger *priv)
>                  * should only be available on trgo trigger which
>                  * is always the first in the list.
>                  */
> -               if (cur == priv->triggers)
> +               if (cur == priv->triggers || cur_is_trgo2)
>                         trig->dev.groups = stm32_trigger_attr_groups;
>
>                 iio_trigger_set_drvdata(trig, priv);
> @@ -584,6 +654,20 @@ bool is_stm32_timer_trigger(struct iio_trigger *trig)
>  }
>  EXPORT_SYMBOL(is_stm32_timer_trigger);
>
> +static void stm32_timer_detect_trgo2(struct stm32_timer_trigger *priv)
> +{
> +       u32 val;
> +
> +       /*
> +        * Master mode selection 2 bits can only be written and read back when
> +        * timer supports it.
> +        */
> +       regmap_update_bits(priv->regmap, TIM_CR2, TIM_CR2_MMS2, TIM_CR2_MMS2);
> +       regmap_read(priv->regmap, TIM_CR2, &val);
> +       regmap_update_bits(priv->regmap, TIM_CR2, TIM_CR2_MMS2, 0);
> +       priv->has_trgo2 = !!val;
> +}
> +
>  static int stm32_timer_trigger_probe(struct platform_device *pdev)
>  {
>         struct device *dev = &pdev->dev;
> @@ -614,6 +698,7 @@ static int stm32_timer_trigger_probe(struct platform_device *pdev)
>         priv->max_arr = ddata->max_arr;
>         priv->triggers = triggers_table[index];
>         priv->valids = valids_table[index];
> +       stm32_timer_detect_trgo2(priv);
>
>         ret = stm32_setup_iio_triggers(priv);
>         if (ret)
> diff --git a/include/linux/iio/timer/stm32-timer-trigger.h b/include/linux/iio/timer/stm32-timer-trigger.h
> index 55535ae..fa7d786 100644
> --- a/include/linux/iio/timer/stm32-timer-trigger.h
> +++ b/include/linux/iio/timer/stm32-timer-trigger.h
> @@ -10,6 +10,7 @@
>  #define _STM32_TIMER_TRIGGER_H_
>
>  #define TIM1_TRGO      "tim1_trgo"
> +#define TIM1_TRGO2     "tim1_trgo2"
>  #define TIM1_CH1       "tim1_ch1"
>  #define TIM1_CH2       "tim1_ch2"
>  #define TIM1_CH3       "tim1_ch3"
> @@ -44,6 +45,7 @@
>  #define TIM7_TRGO      "tim7_trgo"
>
>  #define TIM8_TRGO      "tim8_trgo"
> +#define TIM8_TRGO2     "tim8_trgo2"
>  #define TIM8_CH1       "tim8_ch1"
>  #define TIM8_CH2       "tim8_ch2"
>  #define TIM8_CH3       "tim8_ch3"
> diff --git a/include/linux/mfd/stm32-timers.h b/include/linux/mfd/stm32-timers.h
> index 4a0abbc..ce7346e 100644
> --- a/include/linux/mfd/stm32-timers.h
> +++ b/include/linux/mfd/stm32-timers.h
> @@ -34,6 +34,7 @@
>  #define TIM_CR1_DIR    BIT(4)  /* Counter Direction       */
>  #define TIM_CR1_ARPE   BIT(7)  /* Auto-reload Preload Ena */
>  #define TIM_CR2_MMS    (BIT(4) | BIT(5) | BIT(6)) /* Master mode selection */
> +#define TIM_CR2_MMS2   GENMASK(23, 20) /* Master mode selection 2 */
>  #define TIM_SMCR_SMS   (BIT(0) | BIT(1) | BIT(2)) /* Slave mode selection */
>  #define TIM_SMCR_TS    (BIT(4) | BIT(5) | BIT(6)) /* Trigger selection */
>  #define TIM_DIER_UIE   BIT(0)  /* Update interrupt        */
> @@ -60,6 +61,7 @@
>
>  #define MAX_TIM_PSC            0xFFFF
>  #define TIM_CR2_MMS_SHIFT      4
> +#define TIM_CR2_MMS2_SHIFT     20
>  #define TIM_SMCR_TS_SHIFT      4
>  #define TIM_BDTR_BKF_MASK      0xF
>  #define TIM_BDTR_BKF_SHIFT     16
> --
> 1.9.1
>

Acked-by: Benjamin Gaiganrd <benjamin.gaignard at linaro.org>



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