Add data-ready interrupts and trigger support for STK8BA50.
Additional changes:
- read_accel now returns raw acceleration data instead of the
sign_extend32 value
- read_raw will now enable/disable the sensor with each reading
Signed-off-by: Tiberiu Breana <tiberiu.a.breana@xxxxxxxxx>
---
v3:
- addressed Jonathan's comments
- removed trigger_handler's local buffer, as it was unnecessary
- replaced the switch in trigger_handler with a lookup table
- cleaner approach for mutex_unlock in trigger_handler
v2:
- addressed Peter's comments
- added chan_info's shift field
- added an optimization to bulk read all accel channel data
with one i2c operation when requested
---
drivers/iio/accel/stk8ba50.c | 297 +++++++++++++++++++++++++++++++++++++++----
1 file changed, 272 insertions(+), 25 deletions(-)
diff --git a/drivers/iio/accel/stk8ba50.c b/drivers/iio/accel/stk8ba50.c
index 9836880..ec4e5d9 100644
--- a/drivers/iio/accel/stk8ba50.c
+++ b/drivers/iio/accel/stk8ba50.c
@@ -11,11 +11,17 @@
*/
#include <linux/acpi.h>
+#include <linux/gpio/consumer.h>
#include <linux/i2c.h>
+#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/module.h>
+#include <linux/iio/buffer.h>
#include <linux/iio/iio.h>
#include <linux/iio/sysfs.h>
+#include <linux/iio/trigger.h>
+#include <linux/iio/triggered_buffer.h>
+#include <linux/iio/trigger_consumer.h>
#define STK8BA50_REG_XOUT 0x02
#define STK8BA50_REG_YOUT 0x04
@@ -24,6 +30,8 @@
#define STK8BA50_REG_BWSEL 0x10
#define STK8BA50_REG_POWMODE 0x11
#define STK8BA50_REG_SWRST 0x14
+#define STK8BA50_REG_INTEN2 0x17
+#define STK8BA50_REG_INTMAP2 0x1A
#define STK8BA50_MODE_NORMAL 0
#define STK8BA50_MODE_SUSPEND 1
@@ -31,8 +39,14 @@
#define STK8BA50_DATA_SHIFT 6
#define STK8BA50_RESET_CMD 0xB6
#define STK8BA50_SR_1792HZ_IDX 7
+#define STK8BA50_DREADY_INT_MASK 0x10
+#define STK8BA50_DREADY_INT_MAP 0x81
+#define STK8BA50_ALL_CHANNEL_MASK 7
+#define STK8BA50_ALL_CHANNEL_SIZE 6
#define STK8BA50_DRIVER_NAME "stk8ba50"
+#define STK8BA50_GPIO "stk8ba50_gpio"
+#define STK8BA50_IRQ_NAME "stk8ba50_event"
#define STK8BA50_SCALE_AVAIL "0.0384 0.0767 0.1534 0.3069"
@@ -68,14 +82,29 @@ static const struct {
{0x0C, 224}, {0x0D, 448}, {0x0E, 896}, {0x0F, 1792}
};
+/* Used to map scan mask bits to their corresponding channel register. */
+static const int stk8ba50_channel_table[] = {
+ STK8BA50_REG_XOUT,
+ STK8BA50_REG_YOUT,
+ STK8BA50_REG_ZOUT
+};
+
struct stk8ba50_data {
struct i2c_client *client;
struct mutex lock;
int range;
u8 sample_rate_idx;
+ struct iio_trigger *dready_trig;
+ bool dready_trigger_on;
+ /*
+ * 3 x 16-bit channels (10-bit data, 6-bit padding) +
+ * 1 x 16 padding +
+ * 4 x 16 64-bit timestamp
+ */
+ s16 buffer[8];
};
-#define STK8BA50_ACCEL_CHANNEL(reg, axis) { \
+#define STK8BA50_ACCEL_CHANNEL(index, reg, axis) { \
.type = IIO_ACCEL, \
.address = reg, \
.modified = 1, \
@@ -83,12 +112,21 @@ struct stk8ba50_data {
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \
.info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \
BIT(IIO_CHAN_INFO_SAMP_FREQ), \
+ .scan_index = index, \
+ .scan_type = { \
+ .sign = 's', \
+ .realbits = 10, \
+ .storagebits = 16, \
+ .shift = STK8BA50_DATA_SHIFT, \
+ .endianness = IIO_CPU, \
+ }, \
}
static const struct iio_chan_spec stk8ba50_channels[] = {
- STK8BA50_ACCEL_CHANNEL(STK8BA50_REG_XOUT, X),
- STK8BA50_ACCEL_CHANNEL(STK8BA50_REG_YOUT, Y),
- STK8BA50_ACCEL_CHANNEL(STK8BA50_REG_ZOUT, Z),
+ STK8BA50_ACCEL_CHANNEL(0, STK8BA50_REG_XOUT, X),
+ STK8BA50_ACCEL_CHANNEL(1, STK8BA50_REG_YOUT, Y),
+ STK8BA50_ACCEL_CHANNEL(2, STK8BA50_REG_ZOUT, Z),
+ IIO_CHAN_SOFT_TIMESTAMP(3),
};
static IIO_CONST_ATTR(in_accel_scale_available, STK8BA50_SCALE_AVAIL);
@@ -116,7 +154,61 @@ static int stk8ba50_read_accel(struct stk8ba50_data *data, u8 reg)
return ret;
}
- return sign_extend32(ret >> STK8BA50_DATA_SHIFT, 9);
+ return ret;
+}
+
+static int stk8ba50_data_rdy_trigger_set_state(struct iio_trigger *trig,
+ bool state)
+{
+ struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig);
+ struct stk8ba50_data *data = iio_priv(indio_dev);
+ int ret;
+
+ if (state)
+ ret = i2c_smbus_write_byte_data(data->client,
+ STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
+ else
+ ret = i2c_smbus_write_byte_data(data->client,
+ STK8BA50_REG_INTEN2, 0x00);
+
+ if (ret < 0)
+ dev_err(&data->client->dev, "failed to set trigger state\n");
+ else
+ data->dready_trigger_on = state;
+
+ return ret;
+}
+
+static const struct iio_trigger_ops stk8ba50_trigger_ops = {
+ .set_trigger_state = stk8ba50_data_rdy_trigger_set_state,
+ .owner = THIS_MODULE,
+};
+
+static int stk8ba50_set_power(struct stk8ba50_data *data, bool mode)
+{
+ int ret;
+ u8 masked_reg;
+ struct i2c_client *client = data->client;
+
+ ret = i2c_smbus_read_byte_data(client, STK8BA50_REG_POWMODE);
+ if (ret < 0)
+ goto exit_err;
+
+ if (mode)
+ masked_reg = ret | STK8BA50_MODE_POWERBIT;
+ else
+ masked_reg = ret & (~STK8BA50_MODE_POWERBIT);
+
+ ret = i2c_smbus_write_byte_data(client, STK8BA50_REG_POWMODE,
+ masked_reg);
+ if (ret < 0)
+ goto exit_err;
+
+ return ret;
+
+exit_err:
+ dev_err(&client->dev, "failed to change sensor mode\n");
+ return ret;
}
static int stk8ba50_read_raw(struct iio_dev *indio_dev,
@@ -124,11 +216,26 @@ static int stk8ba50_read_raw(struct iio_dev *indio_dev,
int *val, int *val2, long mask)
{
struct stk8ba50_data *data = iio_priv(indio_dev);
+ int ret;
switch (mask) {
case IIO_CHAN_INFO_RAW:
+ if (iio_buffer_enabled(indio_dev))
+ return -EBUSY;
mutex_lock(&data->lock);
- *val = stk8ba50_read_accel(data, chan->address);
+ ret = stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
+ if (ret < 0) {
+ mutex_unlock(&data->lock);
+ return -EINVAL;
+ }
+ ret = stk8ba50_read_accel(data, chan->address);
+ if (ret < 0) {
+ stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
+ mutex_unlock(&data->lock);
+ return -EINVAL;
+ }
+ *val = sign_extend32(ret >> STK8BA50_DATA_SHIFT, 9);
+ stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
mutex_unlock(&data->lock);
return IIO_VAL_INT;
case IIO_CHAN_INFO_SCALE:
@@ -208,30 +315,100 @@ static const struct iio_info stk8ba50_info = {
.attrs = &stk8ba50_attribute_group,
};
-static int stk8ba50_set_power(struct stk8ba50_data *data, bool mode)
+static irqreturn_t stk8ba50_trigger_handler(int irq, void *p)
+{
+ struct iio_poll_func *pf = p;
+ struct iio_dev *indio_dev = pf->indio_dev;
+ struct stk8ba50_data *data = iio_priv(indio_dev);
+ int bit, ret, i = 0;
+
+ mutex_lock(&data->lock);
+ /*
+ * Do a bulk read if all channels are requested,
+ * from 0x02 (XOUT1) to 0x07 (ZOUT2)
+ */
+ if (*(indio_dev->active_scan_mask) == STK8BA50_ALL_CHANNEL_MASK) {
+ ret = i2c_smbus_read_i2c_block_data(data->client,
+ STK8BA50_REG_XOUT,
+ STK8BA50_ALL_CHANNEL_SIZE,
+ (u8 *)data->buffer);
+ if (ret < STK8BA50_ALL_CHANNEL_SIZE) {
+ dev_err(&data->client->dev, "register read failed\n");
+ goto err;
+ }
+ } else {
+ for_each_set_bit(bit, indio_dev->active_scan_mask,
+ indio_dev->masklength) {
+ ret = stk8ba50_read_accel(data,
+ stk8ba50_channel_table[bit]);
+ if (ret < 0)
+ goto err;
+
+ data->buffer[i++] = ret;
+ }
+ }
+ iio_push_to_buffers_with_timestamp(indio_dev, data->buffer,
+ pf->timestamp);
+err:
+ mutex_unlock(&data->lock);
+ iio_trigger_notify_done(indio_dev->trig);
+
+ return IRQ_HANDLED;
+}
+
+static irqreturn_t stk8ba50_data_rdy_trig_poll(int irq, void *private)
{
+ struct iio_dev *indio_dev = private;
+ struct stk8ba50_data *data = iio_priv(indio_dev);
+
+ if (data->dready_trigger_on)
+ iio_trigger_poll(data->dready_trig);
+
+ return IRQ_HANDLED;
+}
+
+static int stk8ba50_buffer_preenable(struct iio_dev *indio_dev)
+{
+ struct stk8ba50_data *data = iio_priv(indio_dev);
+
+ return stk8ba50_set_power(data, STK8BA50_MODE_NORMAL);
+}
+
+static int stk8ba50_buffer_postdisable(struct iio_dev *indio_dev)
+{
+ struct stk8ba50_data *data = iio_priv(indio_dev);
+
+ return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
+}
+
+static const struct iio_buffer_setup_ops stk8ba50_buffer_setup_ops = {
+ .preenable = stk8ba50_buffer_preenable,
+ .postenable = iio_triggered_buffer_postenable,
+ .predisable = iio_triggered_buffer_predisable,
+ .postdisable = stk8ba50_buffer_postdisable,
+};
+
+static int stk8ba50_gpio_probe(struct i2c_client *client)
+{
+ struct device *dev;
+ struct gpio_desc *gpio;
int ret;
- u8 masked_reg;
- struct i2c_client *client = data->client;
- ret = i2c_smbus_read_byte_data(client, STK8BA50_REG_POWMODE);
- if (ret < 0)
- goto exit_err;
+ if (!client)
+ return -EINVAL;
- if (mode)
- masked_reg = ret | STK8BA50_MODE_POWERBIT;
- else
- masked_reg = ret & (~STK8BA50_MODE_POWERBIT);
+ dev = &client->dev;
- ret = i2c_smbus_write_byte_data(client, STK8BA50_REG_POWMODE,
- masked_reg);
- if (ret < 0)
- goto exit_err;
+ /* data ready gpio interrupt pin */
+ gpio = devm_gpiod_get_index(dev, STK8BA50_GPIO, 0, GPIOD_IN);
+ if (IS_ERR(gpio)) {
+ dev_err(dev, "acpi gpio get index failed\n");
+ return PTR_ERR(gpio);
+ }
- return ret;
+ ret = gpiod_to_irq(gpio);
+ dev_dbg(dev, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio), ret);
-exit_err:
- dev_err(&client->dev, "failed to change sensor mode\n");
return ret;
}
@@ -274,14 +451,78 @@ static int stk8ba50_probe(struct i2c_client *client,
/* The default sampling rate is 1792 Hz (maximum) */
data->sample_rate_idx = STK8BA50_SR_1792HZ_IDX;
+ /* Set up interrupts */
+ ret = i2c_smbus_write_byte_data(client,
+ STK8BA50_REG_INTEN2, STK8BA50_DREADY_INT_MASK);
+ if (ret < 0) {
+ dev_err(&client->dev, "failed to set up interrupts\n");
+ goto err_power_off;
+ }
+ ret = i2c_smbus_write_byte_data(client,
+ STK8BA50_REG_INTMAP2, STK8BA50_DREADY_INT_MAP);
+ if (ret < 0) {
+ dev_err(&client->dev, "failed to set up interrupts\n");
+ goto err_power_off;
+ }
+
+ if (client->irq < 0)
+ client->irq = stk8ba50_gpio_probe(client);
+
+ if (client->irq >= 0) {
+ ret = devm_request_threaded_irq(&client->dev, client->irq,
+ stk8ba50_data_rdy_trig_poll,
+ NULL,
+ IRQF_TRIGGER_RISING |
+ IRQF_ONESHOT,
+ STK8BA50_IRQ_NAME,
+ indio_dev);
+ if (ret < 0) {
+ dev_err(&client->dev, "request irq %d failed\n",
+ client->irq);
+ goto err_power_off;
+ }
+
+ data->dready_trig = devm_iio_trigger_alloc(&client->dev,
+ "%s-dev%d",
+ indio_dev->name,
+ indio_dev->id);
+ if (!data->dready_trig) {
+ ret = -ENOMEM;
+ goto err_power_off;
+ }
+
+ data->dready_trig->dev.parent = &client->dev;
+ data->dready_trig->ops = &stk8ba50_trigger_ops;
+ iio_trigger_set_drvdata(data->dready_trig, indio_dev);
+ ret = iio_trigger_register(data->dready_trig);
+ if (ret) {
+ dev_err(&client->dev, "iio trigger register failed\n");
+ goto err_power_off;
+ }
+ }
+
+ ret = iio_triggered_buffer_setup(indio_dev,
+ iio_pollfunc_store_time,
+ stk8ba50_trigger_handler,
+ &stk8ba50_buffer_setup_ops);
+ if (ret < 0) {
+ dev_err(&client->dev, "iio triggered buffer setup failed\n");
+ goto err_trigger_unregister;
+ }
+
ret = iio_device_register(indio_dev);
if (ret < 0) {
dev_err(&client->dev, "device_register failed\n");
- goto err_power_off;
+ goto err_buffer_cleanup;
}
return ret;
+err_buffer_cleanup:
+ iio_triggered_buffer_cleanup(indio_dev);
+err_trigger_unregister:
+ if (data->dready_trig)
+ iio_trigger_unregister(data->dready_trig);
err_power_off:
stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
return ret;
@@ -290,10 +531,16 @@ err_power_off:
static int stk8ba50_remove(struct i2c_client *client)
{
struct iio_dev *indio_dev = i2c_get_clientdata(client);
+ struct stk8ba50_data *data = iio_priv(indio_dev);
iio_device_unregister(indio_dev);
- return stk8ba50_set_power(iio_priv(indio_dev), STK8BA50_MODE_SUSPEND);
+ if (data->dready_trig) {
+ iio_triggered_buffer_cleanup(indio_dev);
+ iio_trigger_unregister(data->dready_trig);
+ }
+
+ return stk8ba50_set_power(data, STK8BA50_MODE_SUSPEND);
}
#ifdef CONFIG_PM_SLEEP
--
1.9.1
--
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