diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/iio/trigger/stm32-timer-trigger.c | 917 |
1 files changed, 917 insertions, 0 deletions
diff --git a/drivers/iio/trigger/stm32-timer-trigger.c b/drivers/iio/trigger/stm32-timer-trigger.c new file mode 100644 index 000000000..e38671b41 --- /dev/null +++ b/drivers/iio/trigger/stm32-timer-trigger.c @@ -0,0 +1,917 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Copyright (C) STMicroelectronics 2016 + * + * Author: Benjamin Gaignard <benjamin.gaignard@st.com> + * + */ + +#include <linux/iio/iio.h> +#include <linux/iio/sysfs.h> +#include <linux/iio/timer/stm32-timer-trigger.h> +#include <linux/iio/trigger.h> +#include <linux/mfd/stm32-timers.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/of_device.h> + +#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_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_TRGO2, TIM8_CH1, TIM8_CH2, TIM8_CH3, TIM8_CH4,}, + { TIM9_TRGO, TIM9_CH1, TIM9_CH2,}, + { TIM10_OC1,}, + { TIM11_OC1,}, + { TIM12_TRGO, TIM12_CH1, TIM12_CH2,}, + { TIM13_OC1,}, + { TIM14_OC1,}, + { TIM15_TRGO,}, + { TIM16_OC1,}, + { TIM17_OC1,}, +}; + +/* List the triggers accepted by each timer */ +static const void *valids_table[][MAX_VALIDS] = { + { TIM5_TRGO, TIM2_TRGO, TIM3_TRGO, TIM4_TRGO,}, + { TIM1_TRGO, TIM8_TRGO, TIM3_TRGO, TIM4_TRGO,}, + { TIM1_TRGO, TIM2_TRGO, TIM5_TRGO, TIM4_TRGO,}, + { TIM1_TRGO, TIM2_TRGO, TIM3_TRGO, TIM8_TRGO,}, + { TIM2_TRGO, TIM3_TRGO, TIM4_TRGO, TIM8_TRGO,}, + { }, /* timer 6 */ + { }, /* timer 7 */ + { TIM1_TRGO, TIM2_TRGO, TIM4_TRGO, TIM5_TRGO,}, + { TIM2_TRGO, TIM3_TRGO, TIM10_OC1, TIM11_OC1,}, + { }, /* timer 10 */ + { }, /* timer 11 */ + { TIM4_TRGO, TIM5_TRGO, TIM13_OC1, TIM14_OC1,}, +}; + +static const void *stm32h7_valids_table[][MAX_VALIDS] = { + { TIM15_TRGO, TIM2_TRGO, TIM3_TRGO, TIM4_TRGO,}, + { TIM1_TRGO, TIM8_TRGO, TIM3_TRGO, TIM4_TRGO,}, + { TIM1_TRGO, TIM2_TRGO, TIM15_TRGO, TIM4_TRGO,}, + { TIM1_TRGO, TIM2_TRGO, TIM3_TRGO, TIM8_TRGO,}, + { TIM1_TRGO, TIM8_TRGO, TIM3_TRGO, TIM4_TRGO,}, + { }, /* timer 6 */ + { }, /* timer 7 */ + { TIM1_TRGO, TIM2_TRGO, TIM4_TRGO, TIM5_TRGO,}, + { }, /* timer 9 */ + { }, /* timer 10 */ + { }, /* timer 11 */ + { TIM4_TRGO, TIM5_TRGO, TIM13_OC1, TIM14_OC1,}, + { }, /* timer 13 */ + { }, /* timer 14 */ + { TIM1_TRGO, TIM3_TRGO, TIM16_OC1, TIM17_OC1,}, + { }, /* timer 16 */ + { }, /* timer 17 */ +}; + +struct stm32_timer_trigger_regs { + u32 cr1; + u32 cr2; + u32 psc; + u32 arr; + u32 cnt; + u32 smcr; +}; + +struct stm32_timer_trigger { + struct device *dev; + struct regmap *regmap; + struct clk *clk; + bool enabled; + u32 max_arr; + const void *triggers; + const void *valids; + bool has_trgo2; + struct mutex lock; /* concurrent sysfs configuration */ + struct list_head tr_list; + struct stm32_timer_trigger_regs bak; +}; + +struct stm32_timer_trigger_cfg { + const void *(*valids_table)[MAX_VALIDS]; + const unsigned int num_valids_table; +}; + +static bool stm32_timer_is_trgo2_name(const char *name) +{ + return !!strstr(name, "trgo2"); +} + +static bool stm32_timer_is_trgo_name(const char *name) +{ + return (!!strstr(name, "trgo") && !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; + int prescaler = 0; + u32 ccer; + + /* Period and prescaler values depends of clock rate */ + div = (unsigned long long)clk_get_rate(priv->clk); + + do_div(div, frequency); + + prd = div; + + /* + * Increase prescaler value until we get a result that fit + * with auto reload register maximum value. + */ + while (div > priv->max_arr) { + prescaler++; + div = prd; + do_div(div, (prescaler + 1)); + } + prd = div; + + if (prescaler > MAX_TIM_PSC) { + dev_err(priv->dev, "prescaler exceeds the maximum value\n"); + return -EINVAL; + } + + /* Check if nobody else use the timer */ + regmap_read(priv->regmap, TIM_CCER, &ccer); + if (ccer & TIM_CCER_CCXE) + return -EBUSY; + + mutex_lock(&priv->lock); + if (!priv->enabled) { + priv->enabled = true; + clk_enable(priv->clk); + } + + regmap_write(priv->regmap, TIM_PSC, prescaler); + regmap_write(priv->regmap, TIM_ARR, prd - 1); + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, TIM_CR1_ARPE); + + /* Force master mode to update mode */ + 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); + + /* Enable controller */ + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, TIM_CR1_CEN); + mutex_unlock(&priv->lock); + + return 0; +} + +static void stm32_timer_stop(struct stm32_timer_trigger *priv, + struct iio_trigger *trig) +{ + u32 ccer; + + regmap_read(priv->regmap, TIM_CCER, &ccer); + if (ccer & TIM_CCER_CCXE) + return; + + mutex_lock(&priv->lock); + /* Stop timer */ + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, 0); + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0); + regmap_write(priv->regmap, TIM_PSC, 0); + regmap_write(priv->regmap, TIM_ARR, 0); + + /* Force disable master mode */ + if (stm32_timer_is_trgo2_name(trig->name)) + regmap_update_bits(priv->regmap, TIM_CR2, TIM_CR2_MMS2, 0); + else + regmap_update_bits(priv->regmap, TIM_CR2, TIM_CR2_MMS, 0); + + /* Make sure that registers are updated */ + regmap_update_bits(priv->regmap, TIM_EGR, TIM_EGR_UG, TIM_EGR_UG); + + if (priv->enabled) { + priv->enabled = false; + clk_disable(priv->clk); + } + mutex_unlock(&priv->lock); +} + +static ssize_t stm32_tt_store_frequency(struct device *dev, + struct device_attribute *attr, + const char *buf, size_t len) +{ + struct iio_trigger *trig = to_iio_trigger(dev); + struct stm32_timer_trigger *priv = iio_trigger_get_drvdata(trig); + unsigned int freq; + int ret; + + ret = kstrtouint(buf, 10, &freq); + if (ret) + return ret; + + if (freq == 0) { + stm32_timer_stop(priv, trig); + } else { + ret = stm32_timer_start(priv, trig, freq); + if (ret) + return ret; + } + + return len; +} + +static ssize_t stm32_tt_read_frequency(struct device *dev, + struct device_attribute *attr, char *buf) +{ + struct iio_trigger *trig = to_iio_trigger(dev); + struct stm32_timer_trigger *priv = iio_trigger_get_drvdata(trig); + u32 psc, arr, cr1; + unsigned long long freq = 0; + + regmap_read(priv->regmap, TIM_CR1, &cr1); + regmap_read(priv->regmap, TIM_PSC, &psc); + regmap_read(priv->regmap, TIM_ARR, &arr); + + if (cr1 & TIM_CR1_CEN) { + freq = (unsigned long long)clk_get_rate(priv->clk); + do_div(freq, psc + 1); + do_div(freq, arr + 1); + } + + return sprintf(buf, "%d\n", (unsigned int)freq); +} + +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", + "update", + "compare_pulse", + "OC1REF", + "OC2REF", + "OC3REF", + "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, + struct device_attribute *attr, + 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); + + 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]); +} + +static ssize_t stm32_tt_store_master_mode(struct device *dev, + struct device_attribute *attr, + 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; + + 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]))) { + mutex_lock(&priv->lock); + if (!priv->enabled) { + /* Clock should be enabled first */ + priv->enabled = true; + clk_enable(priv->clk); + } + regmap_update_bits(priv->regmap, TIM_CR2, mask, + i << shift); + mutex_unlock(&priv->lock); + return len; + } + } + + return -EINVAL; +} + +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, + stm32_tt_store_master_mode, + 0); + +static struct attribute *stm32_trigger_attrs[] = { + &iio_dev_attr_sampling_frequency.dev_attr.attr, + &iio_dev_attr_master_mode.dev_attr.attr, + &iio_dev_attr_master_mode_available.dev_attr.attr, + NULL, +}; + +static const struct attribute_group stm32_trigger_attr_group = { + .attrs = stm32_trigger_attrs, +}; + +static const struct attribute_group *stm32_trigger_attr_groups[] = { + &stm32_trigger_attr_group, + NULL, +}; + +static const struct iio_trigger_ops timer_trigger_ops = { +}; + +static void stm32_unregister_iio_triggers(struct stm32_timer_trigger *priv) +{ + struct iio_trigger *tr; + + list_for_each_entry(tr, &priv->tr_list, alloc_list) + iio_trigger_unregister(tr); +} + +static int stm32_register_iio_triggers(struct stm32_timer_trigger *priv) +{ + int ret; + const char * const *cur = priv->triggers; + + INIT_LIST_HEAD(&priv->tr_list); + + while (cur && *cur) { + struct iio_trigger *trig; + bool cur_is_trgo = stm32_timer_is_trgo_name(*cur); + 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) + return -ENOMEM; + + trig->dev.parent = priv->dev->parent; + trig->ops = &timer_trigger_ops; + + /* + * sampling frequency and master mode attributes + * should only be available on trgo/trgo2 triggers + */ + if (cur_is_trgo || cur_is_trgo2) + trig->dev.groups = stm32_trigger_attr_groups; + + iio_trigger_set_drvdata(trig, priv); + + ret = iio_trigger_register(trig); + if (ret) { + stm32_unregister_iio_triggers(priv); + return ret; + } + + list_add_tail(&trig->alloc_list, &priv->tr_list); + cur++; + } + + return 0; +} + +static int stm32_counter_read_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int *val, int *val2, long mask) +{ + struct stm32_timer_trigger *priv = iio_priv(indio_dev); + u32 dat; + + switch (mask) { + case IIO_CHAN_INFO_RAW: + regmap_read(priv->regmap, TIM_CNT, &dat); + *val = dat; + return IIO_VAL_INT; + + case IIO_CHAN_INFO_ENABLE: + regmap_read(priv->regmap, TIM_CR1, &dat); + *val = (dat & TIM_CR1_CEN) ? 1 : 0; + return IIO_VAL_INT; + + case IIO_CHAN_INFO_SCALE: + regmap_read(priv->regmap, TIM_SMCR, &dat); + dat &= TIM_SMCR_SMS; + + *val = 1; + *val2 = 0; + + /* in quadrature case scale = 0.25 */ + if (dat == 3) + *val2 = 2; + + return IIO_VAL_FRACTIONAL_LOG2; + } + + return -EINVAL; +} + +static int stm32_counter_write_raw(struct iio_dev *indio_dev, + struct iio_chan_spec const *chan, + int val, int val2, long mask) +{ + struct stm32_timer_trigger *priv = iio_priv(indio_dev); + + switch (mask) { + case IIO_CHAN_INFO_RAW: + return regmap_write(priv->regmap, TIM_CNT, val); + + case IIO_CHAN_INFO_SCALE: + /* fixed scale */ + return -EINVAL; + + case IIO_CHAN_INFO_ENABLE: + mutex_lock(&priv->lock); + if (val) { + if (!priv->enabled) { + priv->enabled = true; + clk_enable(priv->clk); + } + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, + TIM_CR1_CEN); + } else { + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, + 0); + if (priv->enabled) { + priv->enabled = false; + clk_disable(priv->clk); + } + } + mutex_unlock(&priv->lock); + return 0; + } + + return -EINVAL; +} + +static int stm32_counter_validate_trigger(struct iio_dev *indio_dev, + struct iio_trigger *trig) +{ + struct stm32_timer_trigger *priv = iio_priv(indio_dev); + const char * const *cur = priv->valids; + unsigned int i = 0; + + if (!is_stm32_timer_trigger(trig)) + return -EINVAL; + + while (cur && *cur) { + if (!strncmp(trig->name, *cur, strlen(trig->name))) { + regmap_update_bits(priv->regmap, + TIM_SMCR, TIM_SMCR_TS, + i << TIM_SMCR_TS_SHIFT); + return 0; + } + cur++; + i++; + } + + return -EINVAL; +} + +static const struct iio_info stm32_trigger_info = { + .validate_trigger = stm32_counter_validate_trigger, + .read_raw = stm32_counter_read_raw, + .write_raw = stm32_counter_write_raw +}; + +static const char *const stm32_trigger_modes[] = { + "trigger", +}; + +static int stm32_set_trigger_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + unsigned int mode) +{ + struct stm32_timer_trigger *priv = iio_priv(indio_dev); + + regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, TIM_SMCR_SMS); + + return 0; +} + +static int stm32_get_trigger_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan) +{ + struct stm32_timer_trigger *priv = iio_priv(indio_dev); + u32 smcr; + + regmap_read(priv->regmap, TIM_SMCR, &smcr); + + return (smcr & TIM_SMCR_SMS) == TIM_SMCR_SMS ? 0 : -EINVAL; +} + +static const struct iio_enum stm32_trigger_mode_enum = { + .items = stm32_trigger_modes, + .num_items = ARRAY_SIZE(stm32_trigger_modes), + .set = stm32_set_trigger_mode, + .get = stm32_get_trigger_mode +}; + +static const char *const stm32_enable_modes[] = { + "always", + "gated", + "triggered", +}; + +static int stm32_enable_mode2sms(int mode) +{ + switch (mode) { + case 0: + return 0; + case 1: + return 5; + case 2: + return 6; + } + + return -EINVAL; +} + +static int stm32_set_enable_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan, + unsigned int mode) +{ + struct stm32_timer_trigger *priv = iio_priv(indio_dev); + int sms = stm32_enable_mode2sms(mode); + + if (sms < 0) + return sms; + /* + * Triggered mode sets CEN bit automatically by hardware. So, first + * enable counter clock, so it can use it. Keeps it in sync with CEN. + */ + mutex_lock(&priv->lock); + if (sms == 6 && !priv->enabled) { + clk_enable(priv->clk); + priv->enabled = true; + } + mutex_unlock(&priv->lock); + + regmap_update_bits(priv->regmap, TIM_SMCR, TIM_SMCR_SMS, sms); + + return 0; +} + +static int stm32_sms2enable_mode(int mode) +{ + switch (mode) { + case 0: + return 0; + case 5: + return 1; + case 6: + return 2; + } + + return -EINVAL; +} + +static int stm32_get_enable_mode(struct iio_dev *indio_dev, + const struct iio_chan_spec *chan) +{ + struct stm32_timer_trigger *priv = iio_priv(indio_dev); + u32 smcr; + + regmap_read(priv->regmap, TIM_SMCR, &smcr); + smcr &= TIM_SMCR_SMS; + + return stm32_sms2enable_mode(smcr); +} + +static const struct iio_enum stm32_enable_mode_enum = { + .items = stm32_enable_modes, + .num_items = ARRAY_SIZE(stm32_enable_modes), + .set = stm32_set_enable_mode, + .get = stm32_get_enable_mode +}; + +static ssize_t stm32_count_get_preset(struct iio_dev *indio_dev, + uintptr_t private, + const struct iio_chan_spec *chan, + char *buf) +{ + struct stm32_timer_trigger *priv = iio_priv(indio_dev); + u32 arr; + + regmap_read(priv->regmap, TIM_ARR, &arr); + + return snprintf(buf, PAGE_SIZE, "%u\n", arr); +} + +static ssize_t stm32_count_set_preset(struct iio_dev *indio_dev, + uintptr_t private, + const struct iio_chan_spec *chan, + const char *buf, size_t len) +{ + struct stm32_timer_trigger *priv = iio_priv(indio_dev); + unsigned int preset; + int ret; + + ret = kstrtouint(buf, 0, &preset); + if (ret) + return ret; + + /* TIMx_ARR register shouldn't be buffered (ARPE=0) */ + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_ARPE, 0); + regmap_write(priv->regmap, TIM_ARR, preset); + + return len; +} + +static const struct iio_chan_spec_ext_info stm32_trigger_count_info[] = { + { + .name = "preset", + .shared = IIO_SEPARATE, + .read = stm32_count_get_preset, + .write = stm32_count_set_preset + }, + IIO_ENUM("enable_mode", IIO_SEPARATE, &stm32_enable_mode_enum), + IIO_ENUM_AVAILABLE("enable_mode", &stm32_enable_mode_enum), + IIO_ENUM("trigger_mode", IIO_SEPARATE, &stm32_trigger_mode_enum), + IIO_ENUM_AVAILABLE("trigger_mode", &stm32_trigger_mode_enum), + {} +}; + +static const struct iio_chan_spec stm32_trigger_channel = { + .type = IIO_COUNT, + .channel = 0, + .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | + BIT(IIO_CHAN_INFO_ENABLE) | + BIT(IIO_CHAN_INFO_SCALE), + .ext_info = stm32_trigger_count_info, + .indexed = 1 +}; + +static struct stm32_timer_trigger *stm32_setup_counter_device(struct device *dev) +{ + struct iio_dev *indio_dev; + int ret; + + indio_dev = devm_iio_device_alloc(dev, + sizeof(struct stm32_timer_trigger)); + if (!indio_dev) + return NULL; + + indio_dev->name = dev_name(dev); + indio_dev->info = &stm32_trigger_info; + indio_dev->modes = INDIO_HARDWARE_TRIGGERED; + indio_dev->num_channels = 1; + indio_dev->channels = &stm32_trigger_channel; + + ret = devm_iio_device_register(dev, indio_dev); + if (ret) + return NULL; + + return iio_priv(indio_dev); +} + +/** + * is_stm32_timer_trigger + * @trig: trigger to be checked + * + * return true if the trigger is a valid stm32 iio timer trigger + * either return false + */ +bool is_stm32_timer_trigger(struct iio_trigger *trig) +{ + return (trig->ops == &timer_trigger_ops); +} +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; + struct stm32_timer_trigger *priv; + struct stm32_timers *ddata = dev_get_drvdata(pdev->dev.parent); + const struct stm32_timer_trigger_cfg *cfg; + unsigned int index; + int ret; + + if (of_property_read_u32(dev->of_node, "reg", &index)) + return -EINVAL; + + cfg = (const struct stm32_timer_trigger_cfg *) + of_match_device(dev->driver->of_match_table, dev)->data; + + if (index >= ARRAY_SIZE(triggers_table) || + index >= cfg->num_valids_table) + return -EINVAL; + + /* Create an IIO device only if we have triggers to be validated */ + if (*cfg->valids_table[index]) + priv = stm32_setup_counter_device(dev); + else + priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); + + if (!priv) + return -ENOMEM; + + priv->dev = dev; + priv->regmap = ddata->regmap; + priv->clk = ddata->clk; + priv->max_arr = ddata->max_arr; + priv->triggers = triggers_table[index]; + priv->valids = cfg->valids_table[index]; + stm32_timer_detect_trgo2(priv); + mutex_init(&priv->lock); + + ret = stm32_register_iio_triggers(priv); + if (ret) + return ret; + + platform_set_drvdata(pdev, priv); + + return 0; +} + +static int stm32_timer_trigger_remove(struct platform_device *pdev) +{ + struct stm32_timer_trigger *priv = platform_get_drvdata(pdev); + u32 val; + + /* Unregister triggers before everything can be safely turned off */ + stm32_unregister_iio_triggers(priv); + + /* Check if nobody else use the timer, then disable it */ + regmap_read(priv->regmap, TIM_CCER, &val); + if (!(val & TIM_CCER_CCXE)) + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0); + + if (priv->enabled) + clk_disable(priv->clk); + + return 0; +} + +static int __maybe_unused stm32_timer_trigger_suspend(struct device *dev) +{ + struct stm32_timer_trigger *priv = dev_get_drvdata(dev); + + /* Only take care of enabled timer: don't disturb other MFD child */ + if (priv->enabled) { + /* Backup registers that may get lost in low power mode */ + regmap_read(priv->regmap, TIM_CR1, &priv->bak.cr1); + regmap_read(priv->regmap, TIM_CR2, &priv->bak.cr2); + regmap_read(priv->regmap, TIM_PSC, &priv->bak.psc); + regmap_read(priv->regmap, TIM_ARR, &priv->bak.arr); + regmap_read(priv->regmap, TIM_CNT, &priv->bak.cnt); + regmap_read(priv->regmap, TIM_SMCR, &priv->bak.smcr); + + /* Disable the timer */ + regmap_update_bits(priv->regmap, TIM_CR1, TIM_CR1_CEN, 0); + clk_disable(priv->clk); + } + + return 0; +} + +static int __maybe_unused stm32_timer_trigger_resume(struct device *dev) +{ + struct stm32_timer_trigger *priv = dev_get_drvdata(dev); + int ret; + + if (priv->enabled) { + ret = clk_enable(priv->clk); + if (ret) + return ret; + + /* restore master/slave modes */ + regmap_write(priv->regmap, TIM_SMCR, priv->bak.smcr); + regmap_write(priv->regmap, TIM_CR2, priv->bak.cr2); + + /* restore sampling_frequency (trgo / trgo2 triggers) */ + regmap_write(priv->regmap, TIM_PSC, priv->bak.psc); + regmap_write(priv->regmap, TIM_ARR, priv->bak.arr); + regmap_write(priv->regmap, TIM_CNT, priv->bak.cnt); + + /* Also re-enables the timer */ + regmap_write(priv->regmap, TIM_CR1, priv->bak.cr1); + } + + return 0; +} + +static SIMPLE_DEV_PM_OPS(stm32_timer_trigger_pm_ops, + stm32_timer_trigger_suspend, + stm32_timer_trigger_resume); + +static const struct stm32_timer_trigger_cfg stm32_timer_trg_cfg = { + .valids_table = valids_table, + .num_valids_table = ARRAY_SIZE(valids_table), +}; + +static const struct stm32_timer_trigger_cfg stm32h7_timer_trg_cfg = { + .valids_table = stm32h7_valids_table, + .num_valids_table = ARRAY_SIZE(stm32h7_valids_table), +}; + +static const struct of_device_id stm32_trig_of_match[] = { + { + .compatible = "st,stm32-timer-trigger", + .data = (void *)&stm32_timer_trg_cfg, + }, { + .compatible = "st,stm32h7-timer-trigger", + .data = (void *)&stm32h7_timer_trg_cfg, + }, + { /* end node */ }, +}; +MODULE_DEVICE_TABLE(of, stm32_trig_of_match); + +static struct platform_driver stm32_timer_trigger_driver = { + .probe = stm32_timer_trigger_probe, + .remove = stm32_timer_trigger_remove, + .driver = { + .name = "stm32-timer-trigger", + .of_match_table = stm32_trig_of_match, + .pm = &stm32_timer_trigger_pm_ops, + }, +}; +module_platform_driver(stm32_timer_trigger_driver); + +MODULE_ALIAS("platform:stm32-timer-trigger"); +MODULE_DESCRIPTION("STMicroelectronics STM32 Timer Trigger driver"); +MODULE_LICENSE("GPL v2"); |