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iio: stm32 trigger: Add support for TRGO2 triggers

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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@st.com>
Acked-by: Benjamin Gaignard <benjamin.gaignard@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>
This commit is contained in:
Fabrice Gasnier 2017-05-02 14:33:45 +02:00 committed by Jonathan Cameron
parent f80ac400ee
commit 6fb34812c2
4 changed files with 151 additions and 14 deletions
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48
Documentation/ABI/testing/sysfs-bus-iio-timer-stm32
View file

@ -16,6 +16,54 @@ 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.
+-----------+ +-------------+ +---------+
| Prescaler +-> | Counter | +-> | Master | TRGO(2)
+-----------+ +--+--------+-+ |-> | Control +-->
| | || +---------+
+--v--------+-+ OCxREF || +---------+
| Chx compare +----------> | Output | ChX
+-----------+-+ | | Control +-->
. | | +---------+
. | | .
+-----------v-+ OC6REF | .
| Ch6 compare +---------+>
+-------------+
Example with: "compare_pulse_OC4REF_r_or_OC6REF_r":
X
X X
X . . X
X . . X
X . . X
count X . . . . X
. . . .
. . . .
+---------------+
OC4REF | . . |
+-+ . . +-+
. +---+ .
OC6REF . | | .
+-------+ +-------+
+-+ +-+
TRGO2 | | | |
+-+ +---+ +---------+
What: /sys/bus/iio/devices/triggerX/master_mode
KernelVersion: 4.11

113
drivers/iio/trigger/stm32-timer-trigger.c
View file

@ -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 char *master_mode_table[] = {
"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)

2
include/linux/iio/timer/stm32-timer-trigger.h
View file

@ -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"

2
include/linux/mfd/stm32-timers.h
View file

@ -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