The Enhanced Capture (ECAP) module can be used to timestamp events
detected on signal input pin. It can be used for time measurements
of pulse train signals.
ECAP module includes 4 timestamp capture registers. For all 4 sequenced
timestamp capture events (0->1->2->3->0->...), edge polarity (falling/rising
edge) can be selected.
This driver leverages counter subsystem to :
- select edge polarity for all 4 capture events (event mode)
- log timestamps for each capture event
Event polarity, and CAP0/1/2/3 timestamps give all the information
about the input pulse train. Further information can easily be computed :
period and/or duty cycle if frequency is constant, elapsed time between
pulses, etc...
Modifications since v5:
- Fix descriptions for capture items in sysfs-bus-counter ABI file
- Modify TI_ECAP_CAPTURE help in Kconfig file
- Replace ecap_event_id enum with defines
- Add callbacks to reset nb_ovf & TSCNT
- Modify action_read callback to serve both clock and input signals
- Modify watch_validate callback
- Replace 'count_cumul' with 'num_overflows' & 'ceiling' components
- Replace one-based index with zero-based index for polarityX & captureX
- Reverse clock & input signal order (0/1)
- Move the check for overflow outside of the for-loop (in ISR)
- Push each CAPx event to respective counter event channels (in ISR)
Userspace commands :
### CLOCK SIGNAL ###
cd /sys/bus/counter/devices/counter0/signal0
# Get frequency
cat frequency
### INPUT SIGNAL ###
cd /sys/bus/counter/devices/counter0/signal1
# Get available polarities for each capture event
cat polarity0_available
cat polarity1_available
cat polarity2_available
cat polarity3_available
# Get polarity for each capture event
cat polarity0
cat polarity1
cat polarity2
cat polarity3
# Set polarity for each capture event
echo rising edge > polarity0
echo falling edge > polarity1
echo rising edge > polarity2
echo falling edge > polarity3
### COUNT ###
cd /sys/bus/counter/devices/counter0/count0
# Get ceiling (counter max value)
cat ceiling
# Reset number of overflows & current timebase counter value
echo 0 > num_overflows
echo 0 > count
# Run ECAP
echo 1 > enable
# Get number of overflows & current timebase counter value
cat num_overflows
cat count
# Get captured timestamps
cat capture0
cat capture1
cat capture2
cat capture3
# Note that counter watches can also be used to get
# data from userspace application
# -> see tools/counter/counter_example.c
# Pause ECAP
echo 0 > enable
Julien Panis (3):
dt-bindings: counter: add ti,am62-ecap-capture.yaml
Documentation: ABI: sysfs-bus-counter: add capture items
counter: ti-ecap-capture: capture driver support for ECAP
Documentation/ABI/testing/sysfs-bus-counter | 45 ++
.../counter/ti,am62-ecap-capture.yaml | 61 ++
drivers/counter/Kconfig | 15 +
drivers/counter/Makefile | 1 +
drivers/counter/ti-ecap-capture.c | 653 ++++++++++++++++++
include/uapi/linux/counter.h | 2 +
6 files changed, 777 insertions(+)
create mode 100644 Documentation/devicetree/bindings/counter/ti,am62-ecap-capture.yaml
create mode 100644 drivers/counter/ti-ecap-capture.c
--
2.37.3
This commit adds capture items to counter ABI file
(e.g. TI ECAP used in capture operating mode).
Signed-off-by: Julien Panis <[email protected]>
---
Documentation/ABI/testing/sysfs-bus-counter | 45 +++++++++++++++++++++
1 file changed, 45 insertions(+)
diff --git a/Documentation/ABI/testing/sysfs-bus-counter b/Documentation/ABI/testing/sysfs-bus-counter
index 06c2b3e27e0b..1e8f88f67a3f 100644
--- a/Documentation/ABI/testing/sysfs-bus-counter
+++ b/Documentation/ABI/testing/sysfs-bus-counter
@@ -203,6 +203,19 @@ Description:
both edges:
Any state transition.
+What: /sys/bus/counter/devices/counterX/countY/num_overflows
+KernelVersion: 6.0
+Contact: [email protected]
+Description:
+ This attribute indicates the number of overflows since count Y start.
+
+What: /sys/bus/counter/devices/counterX/countY/captureZ
+KernelVersion: 6.0
+Contact: [email protected]
+Description:
+ This read-only attributes is a historical capture of the Count Y count data
+ where Z (if present) is the respective capture buffer element offset.
+
What: /sys/bus/counter/devices/counterX/countY/ceiling_component_id
What: /sys/bus/counter/devices/counterX/countY/floor_component_id
What: /sys/bus/counter/devices/counterX/countY/count_mode_component_id
@@ -213,11 +226,15 @@ What: /sys/bus/counter/devices/counterX/countY/prescaler_component_id
What: /sys/bus/counter/devices/counterX/countY/preset_component_id
What: /sys/bus/counter/devices/counterX/countY/preset_enable_component_id
What: /sys/bus/counter/devices/counterX/countY/signalZ_action_component_id
+What: /sys/bus/counter/devices/counterX/countY/num_overflows_component_id
+What: /sys/bus/counter/devices/counterX/countY/captureZ_component_id
What: /sys/bus/counter/devices/counterX/signalY/cable_fault_component_id
What: /sys/bus/counter/devices/counterX/signalY/cable_fault_enable_component_id
What: /sys/bus/counter/devices/counterX/signalY/filter_clock_prescaler_component_id
What: /sys/bus/counter/devices/counterX/signalY/index_polarity_component_id
What: /sys/bus/counter/devices/counterX/signalY/synchronous_mode_component_id
+What: /sys/bus/counter/devices/counterX/signalY/polarityZ_component_id
+What: /sys/bus/counter/devices/counterX/signalY/frequency_component_id
KernelVersion: 5.16
Contact: [email protected]
Description:
@@ -345,3 +362,31 @@ Description:
via index_polarity. The index function (as enabled via
preset_enable) is performed synchronously with the
quadrature clock on the active level of the index input.
+
+What: /sys/bus/counter/devices/counterX/signalY/polarityZ
+KernelVersion: 6.0
+Contact: [email protected]
+Description:
+ Select the signal Y edge polarity where Z (if present) is the
+ respective polarity sequence position. The following polarities
+ are available:
+
+ rising edge:
+ Low state transitions to high state.
+
+ falling edge:
+ High state transitions to low state.
+
+What: /sys/bus/counter/devices/counterX/signalY/polarityZ_available
+KernelVersion: 6.0
+Contact: [email protected]
+Description:
+ Discrete set of available values for the respective polarity Z
+ configuration are listed in this file. Values are delimited by
+ newline characters.
+
+What: /sys/bus/counter/devices/counterX/signalY/frequency
+KernelVersion: 6.0
+Contact: [email protected]
+Description:
+ Read-only attribute that indicates the signal Y frequency, in Hz.
--
2.37.3
ECAP hardware on TI AM62x SoC supports capture feature. It can be used
to timestamp events (falling/rising edges) detected on input signal.
This commit adds capture driver support for ECAP hardware on AM62x SoC.
In the ECAP hardware, capture pin can also be configured to be in
PWM mode. Current implementation only supports capture operating mode.
Hardware also supports timebase sync between multiple instances, but
this driver supports simple independent capture functionality.
Signed-off-by: Julien Panis <[email protected]>
---
drivers/counter/Kconfig | 15 +
drivers/counter/Makefile | 1 +
drivers/counter/ti-ecap-capture.c | 653 ++++++++++++++++++++++++++++++
include/uapi/linux/counter.h | 2 +
4 files changed, 671 insertions(+)
create mode 100644 drivers/counter/ti-ecap-capture.c
diff --git a/drivers/counter/Kconfig b/drivers/counter/Kconfig
index 5edd155f1911..d388bf26f4dc 100644
--- a/drivers/counter/Kconfig
+++ b/drivers/counter/Kconfig
@@ -101,4 +101,19 @@ config INTEL_QEP
To compile this driver as a module, choose M here: the module
will be called intel-qep.
+config TI_ECAP_CAPTURE
+ tristate "TI eCAP capture driver"
+ depends on ARCH_OMAP2PLUS || ARCH_DAVINCI_DA8XX || ARCH_KEYSTONE || ARCH_K3 || COMPILE_TEST
+ depends on HAS_IOMEM
+ select REGMAP_MMIO
+ help
+ Select this option to enable the Texas Instruments Enhanced Capture
+ (eCAP) driver in input mode.
+
+ It can be used to timestamp events (falling/rising edges) detected
+ on ECAP input signal.
+
+ To compile this driver as a module, choose M here: the module
+ will be called ti-ecap-capture.
+
endif # COUNTER
diff --git a/drivers/counter/Makefile b/drivers/counter/Makefile
index 8fde6c100ebc..b9a369e0d4fc 100644
--- a/drivers/counter/Makefile
+++ b/drivers/counter/Makefile
@@ -14,3 +14,4 @@ obj-$(CONFIG_TI_EQEP) += ti-eqep.o
obj-$(CONFIG_FTM_QUADDEC) += ftm-quaddec.o
obj-$(CONFIG_MICROCHIP_TCB_CAPTURE) += microchip-tcb-capture.o
obj-$(CONFIG_INTEL_QEP) += intel-qep.o
+obj-$(CONFIG_TI_ECAP_CAPTURE) += ti-ecap-capture.o
diff --git a/drivers/counter/ti-ecap-capture.c b/drivers/counter/ti-ecap-capture.c
new file mode 100644
index 000000000000..d04bece77f18
--- /dev/null
+++ b/drivers/counter/ti-ecap-capture.c
@@ -0,0 +1,653 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * ECAP Capture driver
+ *
+ * Copyright (C) 2022 Julien Panis <[email protected]>
+ */
+
+#include <linux/atomic.h>
+#include <linux/clk.h>
+#include <linux/counter.h>
+#include <linux/err.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
+#include <linux/regmap.h>
+
+#define ECAP_DRV_NAME "ecap"
+
+/* ECAP event IDs */
+#define ECAP_CEVT1 0
+#define ECAP_CEVT2 1
+#define ECAP_CEVT3 2
+#define ECAP_CEVT4 3
+#define ECAP_CNTOVF 4
+
+#define ECAP_CEVT_LAST ECAP_CEVT4
+#define ECAP_NB_CEVT (ECAP_CEVT_LAST + 1)
+
+#define ECAP_EVT_LAST ECAP_CNTOVF
+#define ECAP_NB_EVT (ECAP_EVT_LAST + 1)
+
+/* Registers */
+#define ECAP_TSCNT_REG 0x00
+
+#define ECAP_CAP_REG(i) (((i) << 2) + 0x08)
+
+#define ECAP_ECCTL_REG 0x28
+#define ECAP_CAPPOL_BIT(i) BIT((i) << 1)
+#define ECAP_EV_MODE_MASK GENMASK(7, 0)
+#define ECAP_CAPLDEN_BIT BIT(8)
+#define ECAP_CONT_ONESHT_BIT BIT(16)
+#define ECAP_STOPVALUE_MASK GENMASK(18, 17)
+#define ECAP_TSCNTSTP_BIT BIT(20)
+#define ECAP_SYNCO_DIS_MASK GENMASK(23, 22)
+#define ECAP_CAP_APWM_BIT BIT(25)
+#define ECAP_ECCTL_EN_MASK (ECAP_CAPLDEN_BIT | ECAP_TSCNTSTP_BIT)
+#define ECAP_ECCTL_CFG_MASK (ECAP_SYNCO_DIS_MASK | ECAP_STOPVALUE_MASK \
+ | ECAP_ECCTL_EN_MASK | ECAP_CAP_APWM_BIT \
+ | ECAP_CONT_ONESHT_BIT)
+
+#define ECAP_ECINT_EN_FLG_REG 0x2c
+#define ECAP_EVT_EN_MASK GENMASK(ECAP_NB_EVT, ECAP_NB_CEVT)
+#define ECAP_EVT_FLG_BIT(i) BIT((i) + 17)
+
+#define ECAP_ECINT_CLR_FRC_REG 0x30
+#define ECAP_INT_CLR_BIT BIT(0)
+#define ECAP_EVT_CLR_BIT(i) BIT((i) + 1)
+#define ECAP_EVT_CLR_MASK GENMASK(ECAP_NB_EVT, 0)
+
+#define ECAP_PID_REG 0x5c
+
+/*
+ * Event modes
+ * One bit for each CAPx register : 1 = falling edge / 0 = rising edge
+ * e.g. mode = 13 = 0xd = 0b1101
+ * -> falling edge for CAP1-3-4 / rising edge for CAP2
+ */
+#define ECAP_EV_MODE_BIT(i) BIT(i)
+
+/* ECAP signals */
+#define ECAP_CLOCK_SIG 0
+#define ECAP_INPUT_SIG 1
+
+static const struct regmap_config ecap_cnt_regmap_config = {
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ .max_register = ECAP_PID_REG,
+};
+
+/**
+ * struct ecap_cnt_dev - device private data structure
+ * @enabled: device state
+ * @clk: device clock
+ * @regmap: device register map
+ * @nb_ovf: number of overflows since capture start
+ * @pm_ctx: device context for PM operations
+ */
+struct ecap_cnt_dev {
+ bool enabled;
+ struct clk *clk;
+ struct regmap *regmap;
+ atomic_t nb_ovf;
+ struct {
+ u8 ev_mode;
+ u64 time_cntr;
+ } pm_ctx;
+};
+
+static u8 ecap_cnt_capture_get_evmode(struct counter_device *counter)
+{
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter);
+ u8 ev_mode = 0;
+ unsigned int regval;
+ int i;
+
+ pm_runtime_get_sync(counter->parent);
+ regmap_read(ecap_dev->regmap, ECAP_ECCTL_REG, ®val);
+ pm_runtime_put_sync(counter->parent);
+
+ for (i = 0 ; i < ECAP_NB_CEVT ; i++) {
+ if (regval & ECAP_CAPPOL_BIT(i))
+ ev_mode |= ECAP_EV_MODE_BIT(i);
+ }
+
+ return ev_mode;
+}
+
+static void ecap_cnt_capture_set_evmode(struct counter_device *counter, u8 ev_mode)
+{
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter);
+ unsigned int regval = 0;
+ int i;
+
+ for (i = 0 ; i < ECAP_NB_CEVT ; i++) {
+ if (ev_mode & ECAP_EV_MODE_BIT(i))
+ regval |= ECAP_CAPPOL_BIT(i);
+ }
+
+ pm_runtime_get_sync(counter->parent);
+ regmap_update_bits(ecap_dev->regmap, ECAP_ECCTL_REG, ECAP_EV_MODE_MASK, regval);
+ pm_runtime_put_sync(counter->parent);
+}
+
+static void ecap_cnt_capture_enable(struct counter_device *counter)
+{
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter);
+
+ pm_runtime_get_sync(counter->parent);
+
+ /* Enable interrupts on events */
+ regmap_update_bits(ecap_dev->regmap, ECAP_ECINT_EN_FLG_REG,
+ ECAP_EVT_EN_MASK, ECAP_EVT_EN_MASK);
+
+ /* Run counter */
+ regmap_update_bits(ecap_dev->regmap, ECAP_ECCTL_REG, ECAP_ECCTL_CFG_MASK,
+ ECAP_SYNCO_DIS_MASK | ECAP_STOPVALUE_MASK | ECAP_ECCTL_EN_MASK);
+}
+
+static void ecap_cnt_capture_disable(struct counter_device *counter)
+{
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter);
+
+ /* Disable interrupts on events */
+ regmap_update_bits(ecap_dev->regmap, ECAP_ECINT_EN_FLG_REG, ECAP_EVT_EN_MASK, 0);
+
+ /* Stop counter */
+ regmap_update_bits(ecap_dev->regmap, ECAP_ECCTL_REG, ECAP_ECCTL_EN_MASK, 0);
+
+ pm_runtime_put_sync(counter->parent);
+}
+
+static int ecap_cnt_count_get_val(struct counter_device *counter, unsigned int reg, u64 *val)
+{
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter);
+ unsigned int regval;
+
+ pm_runtime_get_sync(counter->parent);
+ regmap_read(ecap_dev->regmap, reg, ®val);
+ pm_runtime_put_sync(counter->parent);
+
+ *val = regval;
+
+ return 0;
+}
+
+static int ecap_cnt_count_set_val(struct counter_device *counter, unsigned int reg, u64 val)
+{
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter);
+
+ pm_runtime_get_sync(counter->parent);
+ regmap_write(ecap_dev->regmap, reg, val);
+ pm_runtime_put_sync(counter->parent);
+
+ return 0;
+}
+
+static inline int ecap_cnt_count_read(struct counter_device *counter,
+ struct counter_count *count, u64 *val)
+{
+ return ecap_cnt_count_get_val(counter, ECAP_TSCNT_REG, val);
+}
+
+static int ecap_cnt_count_write(struct counter_device *counter,
+ struct counter_count *count, u64 val)
+{
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter);
+
+ if (ecap_dev->enabled)
+ return -EBUSY;
+ if (val > 0)
+ return -EINVAL;
+
+ return ecap_cnt_count_set_val(counter, ECAP_TSCNT_REG, val);
+}
+
+static int ecap_cnt_function_read(struct counter_device *counter,
+ struct counter_count *count,
+ enum counter_function *function)
+{
+ *function = COUNTER_FUNCTION_INCREASE;
+
+ return 0;
+}
+
+static int ecap_cnt_action_read(struct counter_device *counter,
+ struct counter_count *count,
+ struct counter_synapse *synapse,
+ enum counter_synapse_action *action)
+{
+ *action = (synapse->signal->id == ECAP_CLOCK_SIG) ?
+ COUNTER_SYNAPSE_ACTION_RISING_EDGE :
+ COUNTER_SYNAPSE_ACTION_NONE;
+
+ return 0;
+}
+
+static int ecap_cnt_watch_validate(struct counter_device *counter,
+ const struct counter_watch *watch)
+{
+ if ((watch->channel <= ECAP_CEVT_LAST && watch->event == COUNTER_EVENT_CAPTURE) ||
+ (watch->channel == ECAP_CNTOVF && watch->event == COUNTER_EVENT_OVERFLOW))
+ return 0;
+
+ return -EINVAL;
+}
+
+static int ecap_cnt_clk_get_freq(struct counter_device *counter,
+ struct counter_signal *signal, u64 *freq)
+{
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter);
+
+ *freq = clk_get_rate(ecap_dev->clk);
+
+ return 0;
+}
+
+static int ecap_cnt_cap_get_pol(struct counter_device *counter,
+ struct counter_signal *signal,
+ u8 inst, u32 *pol)
+{
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter);
+
+ pm_runtime_get_sync(counter->parent);
+ *pol = regmap_test_bits(ecap_dev->regmap, ECAP_ECCTL_REG, ECAP_CAPPOL_BIT(inst));
+ pm_runtime_put_sync(counter->parent);
+
+ return 0;
+}
+
+static int ecap_cnt_cap_set_pol(struct counter_device *counter,
+ struct counter_signal *signal,
+ u8 inst, u32 pol)
+{
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter);
+
+ if (ecap_dev->enabled)
+ return -EBUSY;
+
+ pm_runtime_get_sync(counter->parent);
+ if (pol)
+ regmap_set_bits(ecap_dev->regmap, ECAP_ECCTL_REG, ECAP_CAPPOL_BIT(inst));
+ else
+ regmap_clear_bits(ecap_dev->regmap, ECAP_ECCTL_REG, ECAP_CAPPOL_BIT(inst));
+ pm_runtime_put_sync(counter->parent);
+
+ return 0;
+}
+
+static inline int ecap_cnt_cap_read(struct counter_device *counter,
+ struct counter_count *count,
+ u8 inst, u64 *cap)
+{
+ return ecap_cnt_count_get_val(counter, ECAP_CAP_REG(inst), cap);
+}
+
+#define ECAP_CAP_GET_POL(i) int ecap_cnt_cap##i##_get_pol(struct counter_device *counter, \
+ struct counter_signal *signal, \
+ u32 *pol) \
+{ \
+ return ecap_cnt_cap_get_pol(counter, signal, i, pol); \
+}
+
+#define ECAP_CAP_SET_POL(i) int ecap_cnt_cap##i##_set_pol(struct counter_device *counter, \
+ struct counter_signal *signal, \
+ u32 pol) \
+{ \
+ return ecap_cnt_cap_set_pol(counter, signal, i, pol); \
+}
+
+#define ECAP_CAP_READ(i) int ecap_cnt_cap##i##_read(struct counter_device *counter, \
+ struct counter_count *count, \
+ u64 *cap) \
+{ \
+ return ecap_cnt_cap_read(counter, count, i, cap); \
+}
+
+static inline ECAP_CAP_GET_POL(0)
+static inline ECAP_CAP_GET_POL(1)
+static inline ECAP_CAP_GET_POL(2)
+static inline ECAP_CAP_GET_POL(3)
+static inline ECAP_CAP_SET_POL(0)
+static inline ECAP_CAP_SET_POL(1)
+static inline ECAP_CAP_SET_POL(2)
+static inline ECAP_CAP_SET_POL(3)
+static inline ECAP_CAP_READ(0)
+static inline ECAP_CAP_READ(1)
+static inline ECAP_CAP_READ(2)
+static inline ECAP_CAP_READ(3)
+
+static int ecap_cnt_nb_ovf_read(struct counter_device *counter,
+ struct counter_count *count, u64 *val)
+{
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter);
+
+ *val = atomic_read(&ecap_dev->nb_ovf);
+
+ return 0;
+}
+
+static int ecap_cnt_nb_ovf_write(struct counter_device *counter,
+ struct counter_count *count, u64 val)
+{
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter);
+
+ if (ecap_dev->enabled)
+ return -EBUSY;
+ if (val > 0)
+ return -EINVAL;
+
+ atomic_set(&ecap_dev->nb_ovf, val);
+
+ return 0;
+}
+
+static int ecap_cnt_ceiling_read(struct counter_device *counter,
+ struct counter_count *count, u64 *val)
+{
+ *val = U32_MAX;
+
+ return 0;
+}
+
+static int ecap_cnt_enable_read(struct counter_device *counter,
+ struct counter_count *count, u8 *enable)
+{
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter);
+
+ *enable = ecap_dev->enabled;
+
+ return 0;
+}
+
+static int ecap_cnt_enable_write(struct counter_device *counter,
+ struct counter_count *count, u8 enable)
+{
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter);
+
+ if (enable == ecap_dev->enabled)
+ return 0;
+ if (enable)
+ ecap_cnt_capture_enable(counter);
+ else
+ ecap_cnt_capture_disable(counter);
+ ecap_dev->enabled = enable;
+
+ return 0;
+}
+
+static const struct counter_ops ecap_cnt_ops = {
+ .count_read = ecap_cnt_count_read,
+ .count_write = ecap_cnt_count_write,
+ .function_read = ecap_cnt_function_read,
+ .action_read = ecap_cnt_action_read,
+ .watch_validate = ecap_cnt_watch_validate,
+};
+
+static const enum counter_function ecap_cnt_functions[] = {
+ COUNTER_FUNCTION_INCREASE,
+};
+
+static const enum counter_synapse_action ecap_cnt_clock_actions[] = {
+ COUNTER_SYNAPSE_ACTION_RISING_EDGE,
+};
+
+static const enum counter_synapse_action ecap_cnt_input_actions[] = {
+ COUNTER_SYNAPSE_ACTION_NONE,
+};
+
+static const char *const ecap_cnt_cap_polarities[] = {
+ "rising edge",
+ "falling edge",
+};
+
+static DEFINE_COUNTER_ENUM(ecap_cnt_cap_avail_pol, ecap_cnt_cap_polarities);
+
+static struct counter_comp ecap_cnt_clock_ext[] = {
+ COUNTER_COMP_SIGNAL_U64("frequency", ecap_cnt_clk_get_freq, NULL),
+};
+
+static struct counter_comp ecap_cnt_signal_ext[] = {
+ COUNTER_COMP_SIGNAL_ENUM("polarity0", ecap_cnt_cap0_get_pol,
+ ecap_cnt_cap0_set_pol, ecap_cnt_cap_avail_pol),
+ COUNTER_COMP_SIGNAL_ENUM("polarity1", ecap_cnt_cap1_get_pol,
+ ecap_cnt_cap1_set_pol, ecap_cnt_cap_avail_pol),
+ COUNTER_COMP_SIGNAL_ENUM("polarity2", ecap_cnt_cap2_get_pol,
+ ecap_cnt_cap2_set_pol, ecap_cnt_cap_avail_pol),
+ COUNTER_COMP_SIGNAL_ENUM("polarity3", ecap_cnt_cap3_get_pol,
+ ecap_cnt_cap3_set_pol, ecap_cnt_cap_avail_pol),
+};
+
+static struct counter_signal ecap_cnt_signals[] = {
+ {
+ .id = ECAP_CLOCK_SIG,
+ .name = "Clock Signal",
+ .ext = ecap_cnt_clock_ext,
+ .num_ext = ARRAY_SIZE(ecap_cnt_clock_ext),
+ },
+ {
+ .id = ECAP_INPUT_SIG,
+ .name = "Input Signal",
+ .ext = ecap_cnt_signal_ext,
+ .num_ext = ARRAY_SIZE(ecap_cnt_signal_ext),
+ },
+};
+
+static struct counter_synapse ecap_cnt_synapses[] = {
+ {
+ .actions_list = ecap_cnt_clock_actions,
+ .num_actions = ARRAY_SIZE(ecap_cnt_clock_actions),
+ .signal = &ecap_cnt_signals[ECAP_CLOCK_SIG],
+ },
+ {
+ .actions_list = ecap_cnt_input_actions,
+ .num_actions = ARRAY_SIZE(ecap_cnt_input_actions),
+ .signal = &ecap_cnt_signals[ECAP_INPUT_SIG],
+ },
+};
+
+static struct counter_comp ecap_cnt_count_ext[] = {
+ COUNTER_COMP_COUNT_U64("capture0", ecap_cnt_cap0_read, NULL),
+ COUNTER_COMP_COUNT_U64("capture1", ecap_cnt_cap1_read, NULL),
+ COUNTER_COMP_COUNT_U64("capture2", ecap_cnt_cap2_read, NULL),
+ COUNTER_COMP_COUNT_U64("capture3", ecap_cnt_cap3_read, NULL),
+ COUNTER_COMP_COUNT_U64("num_overflows", ecap_cnt_nb_ovf_read, ecap_cnt_nb_ovf_write),
+ COUNTER_COMP_CEILING(ecap_cnt_ceiling_read, NULL),
+ COUNTER_COMP_ENABLE(ecap_cnt_enable_read, ecap_cnt_enable_write),
+};
+
+static struct counter_count ecap_cnt_counts[] = {
+ {
+ .id = 0,
+ .name = "Timestamp Counter",
+ .functions_list = ecap_cnt_functions,
+ .num_functions = ARRAY_SIZE(ecap_cnt_functions),
+ .synapses = ecap_cnt_synapses,
+ .num_synapses = ARRAY_SIZE(ecap_cnt_synapses),
+ .ext = ecap_cnt_count_ext,
+ .num_ext = ARRAY_SIZE(ecap_cnt_count_ext),
+ },
+};
+
+static irqreturn_t ecap_cnt_isr(int irq, void *dev_id)
+{
+ struct counter_device *counter_dev = dev_id;
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter_dev);
+ unsigned int clr = 0;
+ unsigned int flg;
+ int i;
+
+ regmap_read(ecap_dev->regmap, ECAP_ECINT_EN_FLG_REG, &flg);
+
+ /* Check capture events */
+ for (i = 0 ; i < ECAP_NB_CEVT ; i++) {
+ if (flg & ECAP_EVT_FLG_BIT(i)) {
+ counter_push_event(counter_dev, COUNTER_EVENT_CAPTURE, i);
+ clr |= ECAP_EVT_CLR_BIT(i);
+ }
+ }
+
+ /* Check counter overflow */
+ if (flg & ECAP_EVT_FLG_BIT(ECAP_CNTOVF)) {
+ atomic_inc(&ecap_dev->nb_ovf);
+ counter_push_event(counter_dev, COUNTER_EVENT_OVERFLOW, ECAP_CNTOVF);
+ clr |= ECAP_EVT_CLR_BIT(ECAP_CNTOVF);
+ }
+
+ clr |= ECAP_INT_CLR_BIT;
+ regmap_update_bits(ecap_dev->regmap, ECAP_ECINT_CLR_FRC_REG, ECAP_EVT_CLR_MASK, clr);
+
+ return IRQ_HANDLED;
+}
+
+static void ecap_cnt_pm_disable(void *dev)
+{
+ pm_runtime_disable(dev);
+}
+
+static int ecap_cnt_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct ecap_cnt_dev *ecap_dev;
+ struct counter_device *counter_dev;
+ void __iomem *mmio_base;
+ unsigned long clk_rate;
+ int ret;
+
+ counter_dev = devm_counter_alloc(dev, sizeof(*ecap_dev));
+ if (IS_ERR(counter_dev))
+ return PTR_ERR(counter_dev);
+
+ counter_dev->name = ECAP_DRV_NAME;
+ counter_dev->parent = dev;
+ counter_dev->ops = &ecap_cnt_ops;
+ counter_dev->signals = ecap_cnt_signals;
+ counter_dev->num_signals = ARRAY_SIZE(ecap_cnt_signals);
+ counter_dev->counts = ecap_cnt_counts;
+ counter_dev->num_counts = ARRAY_SIZE(ecap_cnt_counts);
+
+ ecap_dev = counter_priv(counter_dev);
+
+ ecap_dev->clk = devm_clk_get_enabled(dev, "fck");
+ if (IS_ERR(ecap_dev->clk))
+ return dev_err_probe(dev, PTR_ERR(ecap_dev->clk), "failed to get clock\n");
+
+ clk_rate = clk_get_rate(ecap_dev->clk);
+ if (!clk_rate) {
+ dev_err(dev, "failed to get clock rate\n");
+ return -EINVAL;
+ }
+
+ mmio_base = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(mmio_base))
+ return PTR_ERR(mmio_base);
+
+ ecap_dev->regmap = devm_regmap_init_mmio(dev, mmio_base, &ecap_cnt_regmap_config);
+ if (IS_ERR(ecap_dev->regmap))
+ return dev_err_probe(dev, PTR_ERR(ecap_dev->regmap), "failed to init regmap\n");
+
+ ret = platform_get_irq(pdev, 0);
+ if (ret < 0)
+ return dev_err_probe(dev, ret, "failed to get irq\n");
+
+ ret = devm_request_irq(dev, ret, ecap_cnt_isr, 0, pdev->name, counter_dev);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to request irq\n");
+
+ platform_set_drvdata(pdev, counter_dev);
+
+ pm_runtime_enable(dev);
+
+ /* Register a cleanup callback to care for disabling PM */
+ ret = devm_add_action_or_reset(dev, ecap_cnt_pm_disable, dev);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to add pm disable action\n");
+
+ ecap_cnt_capture_set_evmode(counter_dev, 0);
+
+ ret = devm_counter_add(dev, counter_dev);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to add counter\n");
+
+ return 0;
+}
+
+static int ecap_cnt_remove(struct platform_device *pdev)
+{
+ struct counter_device *counter_dev = platform_get_drvdata(pdev);
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter_dev);
+
+ if (ecap_dev->enabled)
+ ecap_cnt_capture_disable(counter_dev);
+
+ return 0;
+}
+
+static int ecap_cnt_suspend(struct device *dev)
+{
+ struct counter_device *counter_dev = dev_get_drvdata(dev);
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter_dev);
+
+ /* If eCAP is running, stop capture then save timestamp counter */
+ if (ecap_dev->enabled) {
+ /*
+ * Disabling capture has the following effects:
+ * - interrupts are disabled
+ * - loading of capture registers is disabled
+ * - timebase counter is stopped
+ */
+ ecap_cnt_capture_disable(counter_dev);
+ ecap_cnt_count_get_val(counter_dev, ECAP_TSCNT_REG, &ecap_dev->pm_ctx.time_cntr);
+ }
+
+ ecap_dev->pm_ctx.ev_mode = ecap_cnt_capture_get_evmode(counter_dev);
+
+ clk_disable(ecap_dev->clk);
+
+ return 0;
+}
+
+static int ecap_cnt_resume(struct device *dev)
+{
+ struct counter_device *counter_dev = dev_get_drvdata(dev);
+ struct ecap_cnt_dev *ecap_dev = counter_priv(counter_dev);
+
+ clk_enable(ecap_dev->clk);
+
+ ecap_cnt_capture_set_evmode(counter_dev, ecap_dev->pm_ctx.ev_mode);
+
+ /* If eCAP was running, restore timestamp counter then run capture */
+ if (ecap_dev->enabled) {
+ ecap_cnt_count_set_val(counter_dev, ECAP_TSCNT_REG, ecap_dev->pm_ctx.time_cntr);
+ ecap_cnt_capture_enable(counter_dev);
+ }
+
+ return 0;
+}
+
+static DEFINE_SIMPLE_DEV_PM_OPS(ecap_cnt_pm_ops, ecap_cnt_suspend, ecap_cnt_resume);
+
+static const struct of_device_id ecap_cnt_of_match[] = {
+ { .compatible = "ti,am62-ecap-capture" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, ecap_cnt_of_match);
+
+static struct platform_driver ecap_cnt_driver = {
+ .probe = ecap_cnt_probe,
+ .remove = ecap_cnt_remove,
+ .driver = {
+ .name = "ecap-capture",
+ .of_match_table = ecap_cnt_of_match,
+ .pm = pm_sleep_ptr(&ecap_cnt_pm_ops),
+ },
+};
+module_platform_driver(ecap_cnt_driver);
+
+MODULE_DESCRIPTION("ECAP Capture driver");
+MODULE_AUTHOR("Julien Panis <[email protected]>");
+MODULE_LICENSE("GPL");
diff --git a/include/uapi/linux/counter.h b/include/uapi/linux/counter.h
index 96c5ffd368ad..4c5372c6f2a3 100644
--- a/include/uapi/linux/counter.h
+++ b/include/uapi/linux/counter.h
@@ -63,6 +63,8 @@ enum counter_event_type {
COUNTER_EVENT_INDEX,
/* State of counter is changed */
COUNTER_EVENT_CHANGE_OF_STATE,
+ /* Count value is captured */
+ COUNTER_EVENT_CAPTURE,
};
/**
--
2.37.3
This commit adds a YAML binding for TI ECAP used in capture operating mode.
Signed-off-by: Julien Panis <[email protected]>
Reviewed-by: Krzysztof Kozlowski <[email protected]>
---
.../counter/ti,am62-ecap-capture.yaml | 61 +++++++++++++++++++
1 file changed, 61 insertions(+)
create mode 100644 Documentation/devicetree/bindings/counter/ti,am62-ecap-capture.yaml
diff --git a/Documentation/devicetree/bindings/counter/ti,am62-ecap-capture.yaml b/Documentation/devicetree/bindings/counter/ti,am62-ecap-capture.yaml
new file mode 100644
index 000000000000..4e0b2d2b303e
--- /dev/null
+++ b/Documentation/devicetree/bindings/counter/ti,am62-ecap-capture.yaml
@@ -0,0 +1,61 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/counter/ti,am62-ecap-capture.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Texas Instruments Enhanced Capture (eCAP) Module
+
+maintainers:
+ - Julien Panis <[email protected]>
+
+description: |
+ The eCAP module resources can be used to capture timestamps
+ on input signal events (falling/rising edges).
+
+properties:
+ compatible:
+ const: ti,am62-ecap-capture
+
+ reg:
+ maxItems: 1
+
+ interrupts:
+ maxItems: 1
+
+ clocks:
+ maxItems: 1
+
+ clock-names:
+ const: fck
+
+ power-domains:
+ maxItems: 1
+
+required:
+ - compatible
+ - reg
+ - interrupts
+ - clocks
+ - clock-names
+
+additionalProperties: false
+
+examples:
+ - |
+ #include <dt-bindings/interrupt-controller/arm-gic.h>
+ #include <dt-bindings/soc/ti,sci_pm_domain.h>
+
+ soc {
+ #address-cells = <2>;
+ #size-cells = <2>;
+
+ capture@23100000 { /* eCAP in capture mode on am62x */
+ compatible = "ti,am62-ecap-capture";
+ reg = <0x00 0x23100000 0x00 0x100>;
+ interrupts = <GIC_SPI 113 IRQ_TYPE_EDGE_RISING>;
+ power-domains = <&k3_pds 51 TI_SCI_PD_EXCLUSIVE>;
+ clocks = <&k3_clks 51 0>;
+ clock-names = "fck";
+ };
+ };
--
2.37.3