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-rw-r--r--drivers/iio/accel/bmc150-accel.c408
1 files changed, 392 insertions, 16 deletions
diff --git a/drivers/iio/accel/bmc150-accel.c b/drivers/iio/accel/bmc150-accel.c
index f1b80c4c0b35..4026122a7592 100644
--- a/drivers/iio/accel/bmc150-accel.c
+++ b/drivers/iio/accel/bmc150-accel.c
@@ -70,7 +70,9 @@
#define BMC150_ACCEL_INT_MAP_0_BIT_SLOPE BIT(2)
#define BMC150_ACCEL_REG_INT_MAP_1 0x1A
-#define BMC150_ACCEL_INT_MAP_1_BIT_DATA BIT(0)
+#define BMC150_ACCEL_INT_MAP_1_BIT_DATA BIT(0)
+#define BMC150_ACCEL_INT_MAP_1_BIT_FWM BIT(1)
+#define BMC150_ACCEL_INT_MAP_1_BIT_FFULL BIT(2)
#define BMC150_ACCEL_REG_INT_RST_LATCH 0x21
#define BMC150_ACCEL_INT_MODE_LATCH_RESET 0x80
@@ -83,7 +85,9 @@
#define BMC150_ACCEL_INT_EN_BIT_SLP_Z BIT(2)
#define BMC150_ACCEL_REG_INT_EN_1 0x17
-#define BMC150_ACCEL_INT_EN_BIT_DATA_EN BIT(4)
+#define BMC150_ACCEL_INT_EN_BIT_DATA_EN BIT(4)
+#define BMC150_ACCEL_INT_EN_BIT_FFULL_EN BIT(5)
+#define BMC150_ACCEL_INT_EN_BIT_FWM_EN BIT(6)
#define BMC150_ACCEL_REG_INT_OUT_CTRL 0x20
#define BMC150_ACCEL_INT_OUT_CTRL_INT1_LVL BIT(0)
@@ -122,6 +126,12 @@
#define BMC150_ACCEL_AXIS_TO_REG(axis) (BMC150_ACCEL_REG_XOUT_L + (axis * 2))
#define BMC150_AUTO_SUSPEND_DELAY_MS 2000
+#define BMC150_ACCEL_REG_FIFO_STATUS 0x0E
+#define BMC150_ACCEL_REG_FIFO_CONFIG0 0x30
+#define BMC150_ACCEL_REG_FIFO_CONFIG1 0x3E
+#define BMC150_ACCEL_REG_FIFO_DATA 0x3F
+#define BMC150_ACCEL_FIFO_LENGTH 32
+
enum bmc150_accel_axis {
AXIS_X,
AXIS_Y,
@@ -179,13 +189,14 @@ struct bmc150_accel_data {
atomic_t active_intr;
struct bmc150_accel_trigger triggers[BMC150_ACCEL_TRIGGERS];
struct mutex mutex;
+ u8 fifo_mode, watermark;
s16 buffer[8];
u8 bw_bits;
u32 slope_dur;
u32 slope_thres;
u32 range;
int ev_enable_state;
- int64_t timestamp;
+ int64_t timestamp, old_timestamp;
const struct bmc150_accel_chip_info *chip_info;
};
@@ -470,6 +481,12 @@ static const struct bmc150_accel_interrupt_info {
BMC150_ACCEL_INT_EN_BIT_SLP_Y |
BMC150_ACCEL_INT_EN_BIT_SLP_Z
},
+ { /* fifo watermark interrupt */
+ .map_reg = BMC150_ACCEL_REG_INT_MAP_1,
+ .map_bitmask = BMC150_ACCEL_INT_MAP_1_BIT_FWM,
+ .en_reg = BMC150_ACCEL_REG_INT_EN_1,
+ .en_bitmask = BMC150_ACCEL_INT_EN_BIT_FWM_EN,
+ },
};
static void bmc150_accel_interrupts_setup(struct iio_dev *indio_dev,
@@ -823,6 +840,214 @@ static int bmc150_accel_validate_trigger(struct iio_dev *indio_dev,
return -EINVAL;
}
+static ssize_t bmc150_accel_get_fifo_watermark(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+ struct bmc150_accel_data *data = iio_priv(indio_dev);
+ int wm;
+
+ mutex_lock(&data->mutex);
+ wm = data->watermark;
+ mutex_unlock(&data->mutex);
+
+ return sprintf(buf, "%d\n", wm);
+}
+
+static ssize_t bmc150_accel_get_fifo_state(struct device *dev,
+ struct device_attribute *attr,
+ char *buf)
+{
+ struct iio_dev *indio_dev = dev_to_iio_dev(dev);
+ struct bmc150_accel_data *data = iio_priv(indio_dev);
+ bool state;
+
+ mutex_lock(&data->mutex);
+ state = data->fifo_mode;
+ mutex_unlock(&data->mutex);
+
+ return sprintf(buf, "%d\n", state);
+}
+
+static IIO_CONST_ATTR(hwfifo_watermark_min, "1");
+static IIO_CONST_ATTR(hwfifo_watermark_max,
+ __stringify(BMC150_ACCEL_FIFO_LENGTH));
+static IIO_DEVICE_ATTR(hwfifo_enabled, S_IRUGO,
+ bmc150_accel_get_fifo_state, NULL, 0);
+static IIO_DEVICE_ATTR(hwfifo_watermark, S_IRUGO,
+ bmc150_accel_get_fifo_watermark, NULL, 0);
+
+static const struct attribute *bmc150_accel_fifo_attributes[] = {
+ &iio_const_attr_hwfifo_watermark_min.dev_attr.attr,
+ &iio_const_attr_hwfifo_watermark_max.dev_attr.attr,
+ &iio_dev_attr_hwfifo_watermark.dev_attr.attr,
+ &iio_dev_attr_hwfifo_enabled.dev_attr.attr,
+ NULL,
+};
+
+static int bmc150_accel_set_watermark(struct iio_dev *indio_dev, unsigned val)
+{
+ struct bmc150_accel_data *data = iio_priv(indio_dev);
+
+ if (val > BMC150_ACCEL_FIFO_LENGTH)
+ val = BMC150_ACCEL_FIFO_LENGTH;
+
+ mutex_lock(&data->mutex);
+ data->watermark = val;
+ mutex_unlock(&data->mutex);
+
+ return 0;
+}
+
+/*
+ * We must read at least one full frame in one burst, otherwise the rest of the
+ * frame data is discarded.
+ */
+static int bmc150_accel_fifo_transfer(const struct i2c_client *client,
+ char *buffer, int samples)
+{
+ int sample_length = 3 * 2;
+ u8 reg_fifo_data = BMC150_ACCEL_REG_FIFO_DATA;
+ int ret = -EIO;
+
+ if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C)) {
+ struct i2c_msg msg[2] = {
+ {
+ .addr = client->addr,
+ .flags = 0,
+ .buf = &reg_fifo_data,
+ .len = sizeof(reg_fifo_data),
+ },
+ {
+ .addr = client->addr,
+ .flags = I2C_M_RD,
+ .buf = (u8 *)buffer,
+ .len = samples * sample_length,
+ }
+ };
+
+ ret = i2c_transfer(client->adapter, msg, 2);
+ if (ret != 2)
+ ret = -EIO;
+ else
+ ret = 0;
+ } else {
+ int i, step = I2C_SMBUS_BLOCK_MAX / sample_length;
+
+ for (i = 0; i < samples * sample_length; i += step) {
+ ret = i2c_smbus_read_i2c_block_data(client,
+ reg_fifo_data, step,
+ &buffer[i]);
+ if (ret != step) {
+ ret = -EIO;
+ break;
+ }
+
+ ret = 0;
+ }
+ }
+
+ if (ret)
+ dev_err(&client->dev, "Error transferring data from fifo\n");
+
+ return ret;
+}
+
+static int __bmc150_accel_fifo_flush(struct iio_dev *indio_dev,
+ unsigned samples, bool irq)
+{
+ struct bmc150_accel_data *data = iio_priv(indio_dev);
+ int ret, i;
+ u8 count;
+ u16 buffer[BMC150_ACCEL_FIFO_LENGTH * 3];
+ int64_t tstamp;
+ uint64_t sample_period;
+ ret = i2c_smbus_read_byte_data(data->client,
+ BMC150_ACCEL_REG_FIFO_STATUS);
+ if (ret < 0) {
+ dev_err(&data->client->dev, "Error reading reg_fifo_status\n");
+ return ret;
+ }
+
+ count = ret & 0x7F;
+
+ if (!count)
+ return 0;
+
+ /*
+ * If we getting called from IRQ handler we know the stored timestamp is
+ * fairly accurate for the last stored sample. Otherwise, if we are
+ * called as a result of a read operation from userspace and hence
+ * before the watermark interrupt was triggered, take a timestamp
+ * now. We can fall anywhere in between two samples so the error in this
+ * case is at most one sample period.
+ */
+ if (!irq) {
+ data->old_timestamp = data->timestamp;
+ data->timestamp = iio_get_time_ns();
+ }
+
+ /*
+ * Approximate timestamps for each of the sample based on the sampling
+ * frequency, timestamp for last sample and number of samples.
+ *
+ * Note that we can't use the current bandwidth settings to compute the
+ * sample period because the sample rate varies with the device
+ * (e.g. between 31.70ms to 32.20ms for a bandwidth of 15.63HZ). That
+ * small variation adds when we store a large number of samples and
+ * creates significant jitter between the last and first samples in
+ * different batches (e.g. 32ms vs 21ms).
+ *
+ * To avoid this issue we compute the actual sample period ourselves
+ * based on the timestamp delta between the last two flush operations.
+ */
+ sample_period = (data->timestamp - data->old_timestamp);
+ do_div(sample_period, count);
+ tstamp = data->timestamp - (count - 1) * sample_period;
+
+ if (samples && count > samples)
+ count = samples;
+
+ ret = bmc150_accel_fifo_transfer(data->client, (u8 *)buffer, count);
+ if (ret)
+ return ret;
+
+ /*
+ * Ideally we want the IIO core to handle the demux when running in fifo
+ * mode but not when running in triggered buffer mode. Unfortunately
+ * this does not seem to be possible, so stick with driver demux for
+ * now.
+ */
+ for (i = 0; i < count; i++) {
+ u16 sample[8];
+ int j, bit;
+
+ j = 0;
+ for_each_set_bit(bit, indio_dev->active_scan_mask,
+ indio_dev->masklength)
+ memcpy(&sample[j++], &buffer[i * 3 + bit], 2);
+
+ iio_push_to_buffers_with_timestamp(indio_dev, sample, tstamp);
+
+ tstamp += sample_period;
+ }
+
+ return count;
+}
+
+static int bmc150_accel_fifo_flush(struct iio_dev *indio_dev, unsigned samples)
+{
+ struct bmc150_accel_data *data = iio_priv(indio_dev);
+ int ret;
+
+ mutex_lock(&data->mutex);
+ ret = __bmc150_accel_fifo_flush(indio_dev, samples, false);
+ mutex_unlock(&data->mutex);
+
+ return ret;
+}
+
static IIO_CONST_ATTR_SAMP_FREQ_AVAIL(
"7.810000 15.630000 31.250000 62.500000 125 250 500 1000");
@@ -962,6 +1187,20 @@ static const struct iio_info bmc150_accel_info = {
.driver_module = THIS_MODULE,
};
+static const struct iio_info bmc150_accel_info_fifo = {
+ .attrs = &bmc150_accel_attrs_group,
+ .read_raw = bmc150_accel_read_raw,
+ .write_raw = bmc150_accel_write_raw,
+ .read_event_value = bmc150_accel_read_event,
+ .write_event_value = bmc150_accel_write_event,
+ .write_event_config = bmc150_accel_write_event_config,
+ .read_event_config = bmc150_accel_read_event_config,
+ .validate_trigger = bmc150_accel_validate_trigger,
+ .hwfifo_set_watermark = bmc150_accel_set_watermark,
+ .hwfifo_flush_to_buffer = bmc150_accel_fifo_flush,
+ .driver_module = THIS_MODULE,
+};
+
static irqreturn_t bmc150_accel_trigger_handler(int irq, void *p)
{
struct iio_poll_func *pf = p;
@@ -1057,18 +1296,17 @@ static const struct iio_trigger_ops bmc150_accel_trigger_ops = {
.owner = THIS_MODULE,
};
-static irqreturn_t bmc150_accel_event_handler(int irq, void *private)
+static int bmc150_accel_handle_roc_event(struct iio_dev *indio_dev)
{
- struct iio_dev *indio_dev = private;
struct bmc150_accel_data *data = iio_priv(indio_dev);
- int ret;
int dir;
+ int ret;
ret = i2c_smbus_read_byte_data(data->client,
BMC150_ACCEL_REG_INT_STATUS_2);
if (ret < 0) {
dev_err(&data->client->dev, "Error reading reg_int_status_2\n");
- goto ack_intr_status;
+ return ret;
}
if (ret & BMC150_ACCEL_ANY_MOTION_BIT_SIGN)
@@ -1097,35 +1335,73 @@ static irqreturn_t bmc150_accel_event_handler(int irq, void *private)
IIO_EV_TYPE_ROC,
dir),
data->timestamp);
-ack_intr_status:
- if (!data->triggers[BMC150_ACCEL_TRIGGER_DATA_READY].enabled)
+ return ret;
+}
+
+static irqreturn_t bmc150_accel_irq_thread_handler(int irq, void *private)
+{
+ struct iio_dev *indio_dev = private;
+ struct bmc150_accel_data *data = iio_priv(indio_dev);
+ bool ack = false;
+ int ret;
+
+ mutex_lock(&data->mutex);
+
+ if (data->fifo_mode) {
+ ret = __bmc150_accel_fifo_flush(indio_dev,
+ BMC150_ACCEL_FIFO_LENGTH, true);
+ if (ret > 0)
+ ack = true;
+ }
+
+ if (data->ev_enable_state) {
+ ret = bmc150_accel_handle_roc_event(indio_dev);
+ if (ret > 0)
+ ack = true;
+ }
+
+ if (ack) {
ret = i2c_smbus_write_byte_data(data->client,
BMC150_ACCEL_REG_INT_RST_LATCH,
BMC150_ACCEL_INT_MODE_LATCH_INT |
BMC150_ACCEL_INT_MODE_LATCH_RESET);
+ if (ret)
+ dev_err(&data->client->dev, "Error writing reg_int_rst_latch\n");
+ ret = IRQ_HANDLED;
+ } else {
+ ret = IRQ_NONE;
+ }
- return IRQ_HANDLED;
+ mutex_unlock(&data->mutex);
+
+ return ret;
}
-static irqreturn_t bmc150_accel_data_rdy_trig_poll(int irq, void *private)
+static irqreturn_t bmc150_accel_irq_handler(int irq, void *private)
{
struct iio_dev *indio_dev = private;
struct bmc150_accel_data *data = iio_priv(indio_dev);
+ bool ack = false;
int i;
+ data->old_timestamp = data->timestamp;
data->timestamp = iio_get_time_ns();
for (i = 0; i < BMC150_ACCEL_TRIGGERS; i++) {
if (data->triggers[i].enabled) {
iio_trigger_poll(data->triggers[i].indio_trig);
+ ack = true;
break;
}
}
- if (data->ev_enable_state)
+ if (data->ev_enable_state || data->fifo_mode)
return IRQ_WAKE_THREAD;
- else
+
+ if (ack)
return IRQ_HANDLED;
+
+ return IRQ_NONE;
}
static const char *bmc150_accel_match_acpi_device(struct device *dev, int *data)
@@ -1232,6 +1508,94 @@ static int bmc150_accel_triggers_setup(struct iio_dev *indio_dev,
return ret;
}
+#define BMC150_ACCEL_FIFO_MODE_STREAM 0x80
+#define BMC150_ACCEL_FIFO_MODE_FIFO 0x40
+#define BMC150_ACCEL_FIFO_MODE_BYPASS 0x00
+
+static int bmc150_accel_fifo_set_mode(struct bmc150_accel_data *data)
+{
+ u8 reg = BMC150_ACCEL_REG_FIFO_CONFIG1;
+ int ret;
+
+ ret = i2c_smbus_write_byte_data(data->client, reg, data->fifo_mode);
+ if (ret < 0) {
+ dev_err(&data->client->dev, "Error writing reg_fifo_config1\n");
+ return ret;
+ }
+
+ if (!data->fifo_mode)
+ return 0;
+
+ ret = i2c_smbus_write_byte_data(data->client,
+ BMC150_ACCEL_REG_FIFO_CONFIG0,
+ data->watermark);
+ if (ret < 0)
+ dev_err(&data->client->dev, "Error writing reg_fifo_config0\n");
+
+ return ret;
+}
+
+static int bmc150_accel_buffer_postenable(struct iio_dev *indio_dev)
+{
+ struct bmc150_accel_data *data = iio_priv(indio_dev);
+ int ret = 0;
+
+ if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED)
+ return iio_triggered_buffer_postenable(indio_dev);
+
+ mutex_lock(&data->mutex);
+
+ if (!data->watermark)
+ goto out;
+
+ ret = bmc150_accel_set_interrupt(data, BMC150_ACCEL_INT_WATERMARK,
+ true);
+ if (ret)
+ goto out;
+
+ data->fifo_mode = BMC150_ACCEL_FIFO_MODE_FIFO;
+
+ ret = bmc150_accel_fifo_set_mode(data);
+ if (ret) {
+ data->fifo_mode = 0;
+ bmc150_accel_set_interrupt(data, BMC150_ACCEL_INT_WATERMARK,
+ false);
+ }
+
+out:
+ mutex_unlock(&data->mutex);
+
+ return ret;
+}
+
+static int bmc150_accel_buffer_predisable(struct iio_dev *indio_dev)
+{
+ struct bmc150_accel_data *data = iio_priv(indio_dev);
+
+ if (indio_dev->currentmode == INDIO_BUFFER_TRIGGERED)
+ return iio_triggered_buffer_predisable(indio_dev);
+
+ mutex_lock(&data->mutex);
+
+ if (!data->fifo_mode)
+ goto out;
+
+ bmc150_accel_set_interrupt(data, BMC150_ACCEL_INT_WATERMARK, false);
+ __bmc150_accel_fifo_flush(indio_dev, BMC150_ACCEL_FIFO_LENGTH, false);
+ data->fifo_mode = 0;
+ bmc150_accel_fifo_set_mode(data);
+
+out:
+ mutex_unlock(&data->mutex);
+
+ return 0;
+}
+
+static const struct iio_buffer_setup_ops bmc150_accel_buffer_ops = {
+ .postenable = bmc150_accel_buffer_postenable,
+ .predisable = bmc150_accel_buffer_predisable,
+};
+
static int bmc150_accel_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
@@ -1278,8 +1642,8 @@ static int bmc150_accel_probe(struct i2c_client *client,
if (client->irq >= 0) {
ret = devm_request_threaded_irq(
&client->dev, client->irq,
- bmc150_accel_data_rdy_trig_poll,
- bmc150_accel_event_handler,
+ bmc150_accel_irq_handler,
+ bmc150_accel_irq_thread_handler,
IRQF_TRIGGER_RISING,
BMC150_ACCEL_IRQ_NAME,
indio_dev);
@@ -1309,12 +1673,20 @@ static int bmc150_accel_probe(struct i2c_client *client,
ret = iio_triggered_buffer_setup(indio_dev,
&iio_pollfunc_store_time,
bmc150_accel_trigger_handler,
- NULL);
+ &bmc150_accel_buffer_ops);
if (ret < 0) {
dev_err(&client->dev,
"Failed: iio triggered buffer setup\n");
goto err_trigger_unregister;
}
+
+ if (i2c_check_functionality(client->adapter, I2C_FUNC_I2C) ||
+ i2c_check_functionality(client->adapter,
+ I2C_FUNC_SMBUS_READ_I2C_BLOCK)) {
+ indio_dev->modes |= INDIO_BUFFER_SOFTWARE;
+ indio_dev->info = &bmc150_accel_info_fifo;
+ indio_dev->buffer->attrs = bmc150_accel_fifo_attributes;
+ }
}
ret = iio_device_register(indio_dev);
@@ -1386,6 +1758,7 @@ static int bmc150_accel_resume(struct device *dev)
mutex_lock(&data->mutex);
if (atomic_read(&data->active_intr))
bmc150_accel_set_mode(data, BMC150_ACCEL_SLEEP_MODE_NORMAL, 0);
+ bmc150_accel_fifo_set_mode(data);
mutex_unlock(&data->mutex);
return 0;
@@ -1419,6 +1792,9 @@ static int bmc150_accel_runtime_resume(struct device *dev)
ret = bmc150_accel_set_mode(data, BMC150_ACCEL_SLEEP_MODE_NORMAL, 0);
if (ret < 0)
return ret;
+ ret = bmc150_accel_fifo_set_mode(data);
+ if (ret < 0)
+ return ret;
sleep_val = bmc150_accel_get_startup_times(data);
if (sleep_val < 20)