Add st_lsm6dsx_update_bits_locked, st_lsm6dsx_read_locked and
st_lsm6dsx_write_locked utility routines in order to guarantee
the bus access is atomic respect to reg page configuration.
This is a preliminary patch to add i2c sensor hub support since
i2c master registers are accessed through a reg page multiplexer
Signed-off-by: Lorenzo Bianconi <lorenzo.bianconi@xxxxxxxxxx>
---
drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h | 41 +++++++++++
.../iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c | 70 +++++++++----------
drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c | 24 ++++---
3 files changed, 91 insertions(+), 44 deletions(-)
diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
index ef73519a0fb6..ec204d3b4b1f 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h
@@ -148,6 +148,7 @@ struct st_lsm6dsx_sensor {
* @irq: Device interrupt line (I2C or SPI).
* @fifo_lock: Mutex to prevent concurrent access to the hw FIFO.
* @conf_lock: Mutex to prevent concurrent FIFO configuration update.
+ * @page_lock: Mutex to prevent concurrent memory page configuration.
* @fifo_mode: FIFO operating mode supported by the device.
* @enable_mask: Enabled sensor bitmask.
* @ts_sip: Total number of timestamp samples in a given pattern.
@@ -163,6 +164,7 @@ struct st_lsm6dsx_hw {
struct mutex fifo_lock;
struct mutex conf_lock;
+ struct mutex page_lock;
enum st_lsm6dsx_fifo_mode fifo_mode;
u8 enable_mask;
@@ -192,4 +194,43 @@ int st_lsm6dsx_read_fifo(struct st_lsm6dsx_hw *hw);
int st_lsm6dsx_read_tagged_fifo(struct st_lsm6dsx_hw *hw);
int st_lsm6dsx_check_odr(struct st_lsm6dsx_sensor *sensor, u16 odr, u8 *val);
+static inline int
+st_lsm6dsx_update_bits_locked(struct st_lsm6dsx_hw *hw, unsigned int addr,
+ unsigned int mask, unsigned int val)
+{
+ int err;
+
+ mutex_lock(&hw->page_lock);
+ err = regmap_update_bits(hw->regmap, addr, mask, val);
+ mutex_unlock(&hw->page_lock);
+
+ return err;
+}
+
+static inline int
+st_lsm6dsx_read_locked(struct st_lsm6dsx_hw *hw, unsigned int addr,
+ void *val, unsigned int len)
+{
+ int err;
+
+ mutex_lock(&hw->page_lock);
+ err = regmap_bulk_read(hw->regmap, addr, val, len);
+ mutex_unlock(&hw->page_lock);
+
+ return err;
+}
+
+static inline int
+st_lsm6dsx_write_locked(struct st_lsm6dsx_hw *hw, unsigned int addr,
+ unsigned int val)
+{
+ int err;
+
+ mutex_lock(&hw->page_lock);
+ err = regmap_write(hw->regmap, addr, val);
+ mutex_unlock(&hw->page_lock);
+
+ return err;
+}
+
#endif /* ST_LSM6DSX_H */
diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c
index b5263fc522ca..4b3ba0956b5a 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_buffer.c
@@ -142,8 +142,9 @@ static int st_lsm6dsx_update_decimators(struct st_lsm6dsx_hw *hw)
if (dec_reg->addr) {
int val = ST_LSM6DSX_SHIFT_VAL(data, dec_reg->mask);
- err = regmap_update_bits(hw->regmap, dec_reg->addr,
- dec_reg->mask, val);
+ err = st_lsm6dsx_update_bits_locked(hw, dec_reg->addr,
+ dec_reg->mask,
+ val);
if (err < 0)
return err;
}
@@ -162,8 +163,8 @@ static int st_lsm6dsx_update_decimators(struct st_lsm6dsx_hw *hw)
int val, ts_dec = !!hw->ts_sip;
val = ST_LSM6DSX_SHIFT_VAL(ts_dec, ts_dec_reg->mask);
- err = regmap_update_bits(hw->regmap, ts_dec_reg->addr,
- ts_dec_reg->mask, val);
+ err = st_lsm6dsx_update_bits_locked(hw, ts_dec_reg->addr,
+ ts_dec_reg->mask, val);
}
return err;
}
@@ -171,12 +172,12 @@ static int st_lsm6dsx_update_decimators(struct st_lsm6dsx_hw *hw)
int st_lsm6dsx_set_fifo_mode(struct st_lsm6dsx_hw *hw,
enum st_lsm6dsx_fifo_mode fifo_mode)
{
+ unsigned int data;
int err;
- err = regmap_update_bits(hw->regmap, ST_LSM6DSX_REG_FIFO_MODE_ADDR,
- ST_LSM6DSX_FIFO_MODE_MASK,
- FIELD_PREP(ST_LSM6DSX_FIFO_MODE_MASK,
- fifo_mode));
+ data = FIELD_PREP(ST_LSM6DSX_FIFO_MODE_MASK, fifo_mode);
+ err = st_lsm6dsx_update_bits_locked(hw, ST_LSM6DSX_REG_FIFO_MODE_ADDR,
+ ST_LSM6DSX_FIFO_MODE_MASK, data);
if (err < 0)
return err;
@@ -207,15 +208,15 @@ static int st_lsm6dsx_set_fifo_odr(struct st_lsm6dsx_sensor *sensor,
data = 0;
}
val = ST_LSM6DSX_SHIFT_VAL(data, batch_reg->mask);
- return regmap_update_bits(hw->regmap, batch_reg->addr,
- batch_reg->mask, val);
+ return st_lsm6dsx_update_bits_locked(hw, batch_reg->addr,
+ batch_reg->mask, val);
} else {
data = hw->enable_mask ? ST_LSM6DSX_MAX_FIFO_ODR_VAL : 0;
- return regmap_update_bits(hw->regmap,
- ST_LSM6DSX_REG_FIFO_MODE_ADDR,
- ST_LSM6DSX_FIFO_ODR_MASK,
- FIELD_PREP(ST_LSM6DSX_FIFO_ODR_MASK,
- data));
+ return st_lsm6dsx_update_bits_locked(hw,
+ ST_LSM6DSX_REG_FIFO_MODE_ADDR,
+ ST_LSM6DSX_FIFO_ODR_MASK,
+ FIELD_PREP(ST_LSM6DSX_FIFO_ODR_MASK,
+ data));
}
}
@@ -246,19 +247,23 @@ int st_lsm6dsx_update_watermark(struct st_lsm6dsx_sensor *sensor, u16 watermark)
fifo_watermark = (fifo_watermark / hw->sip) * hw->sip;
fifo_watermark = fifo_watermark * hw->settings->fifo_ops.th_wl;
+ mutex_lock(&hw->page_lock);
err = regmap_read(hw->regmap, hw->settings->fifo_ops.fifo_th.addr + 1,
&data);
if (err < 0)
- return err;
+ goto out;
fifo_th_mask = hw->settings->fifo_ops.fifo_th.mask;
fifo_watermark = ((data << 8) & ~fifo_th_mask) |
(fifo_watermark & fifo_th_mask);
wdata = cpu_to_le16(fifo_watermark);
- return regmap_bulk_write(hw->regmap,
- hw->settings->fifo_ops.fifo_th.addr,
- &wdata, sizeof(wdata));
+ err = regmap_bulk_write(hw->regmap,
+ hw->settings->fifo_ops.fifo_th.addr,
+ &wdata, sizeof(wdata));
+out:
+ mutex_unlock(&hw->page_lock);
+ return err;
}
static int st_lsm6dsx_reset_hw_ts(struct st_lsm6dsx_hw *hw)
@@ -267,8 +272,8 @@ static int st_lsm6dsx_reset_hw_ts(struct st_lsm6dsx_hw *hw)
int i, err;
/* reset hw ts counter */
- err = regmap_write(hw->regmap, ST_LSM6DSX_REG_TS_RESET_ADDR,
- ST_LSM6DSX_TS_RESET_VAL);
+ err = st_lsm6dsx_write_locked(hw, ST_LSM6DSX_REG_TS_RESET_ADDR,
+ ST_LSM6DSX_TS_RESET_VAL);
if (err < 0)
return err;
@@ -297,8 +302,8 @@ static inline int st_lsm6dsx_read_block(struct st_lsm6dsx_hw *hw, u8 addr,
while (read_len < data_len) {
word_len = min_t(unsigned int, data_len - read_len,
max_word_len);
- err = regmap_bulk_read(hw->regmap, addr, data + read_len,
- word_len);
+ err = st_lsm6dsx_read_locked(hw, addr, data + read_len,
+ word_len);
if (err < 0)
return err;
read_len += word_len;
@@ -328,9 +333,9 @@ int st_lsm6dsx_read_fifo(struct st_lsm6dsx_hw *hw)
__le16 fifo_status;
s64 ts = 0;
- err = regmap_bulk_read(hw->regmap,
- hw->settings->fifo_ops.fifo_diff.addr,
- &fifo_status, sizeof(fifo_status));
+ err = st_lsm6dsx_read_locked(hw,
+ hw->settings->fifo_ops.fifo_diff.addr,
+ &fifo_status, sizeof(fifo_status));
if (err < 0) {
dev_err(hw->dev, "failed to read fifo status (err=%d)\n",
err);
@@ -455,9 +460,9 @@ int st_lsm6dsx_read_tagged_fifo(struct st_lsm6dsx_hw *hw)
__le16 fifo_status;
s64 ts = 0;
- err = regmap_bulk_read(hw->regmap,
- hw->settings->fifo_ops.fifo_diff.addr,
- &fifo_status, sizeof(fifo_status));
+ err = st_lsm6dsx_read_locked(hw,
+ hw->settings->fifo_ops.fifo_diff.addr,
+ &fifo_status, sizeof(fifo_status));
if (err < 0) {
dev_err(hw->dev, "failed to read fifo status (err=%d)\n",
err);
@@ -536,16 +541,11 @@ int st_lsm6dsx_read_tagged_fifo(struct st_lsm6dsx_hw *hw)
int st_lsm6dsx_flush_fifo(struct st_lsm6dsx_hw *hw)
{
- int err;
-
mutex_lock(&hw->fifo_lock);
-
hw->settings->fifo_ops.read_fifo(hw);
- err = st_lsm6dsx_set_fifo_mode(hw, ST_LSM6DSX_FIFO_BYPASS);
-
mutex_unlock(&hw->fifo_lock);
- return err;
+ return st_lsm6dsx_set_fifo_mode(hw, ST_LSM6DSX_FIFO_BYPASS);
}
static int st_lsm6dsx_update_fifo(struct iio_dev *iio_dev, bool enable)
diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
index 2ad3c610e4b6..c8b993bea757 100644
--- a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
+++ b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c
@@ -421,6 +421,7 @@ static int st_lsm6dsx_set_full_scale(struct st_lsm6dsx_sensor *sensor,
{
struct st_lsm6dsx_hw *hw = sensor->hw;
const struct st_lsm6dsx_reg *reg;
+ unsigned int data;
int i, err;
u8 val;
@@ -433,8 +434,8 @@ static int st_lsm6dsx_set_full_scale(struct st_lsm6dsx_sensor *sensor,
val = st_lsm6dsx_fs_table[sensor->id].fs_avl[i].val;
reg = &st_lsm6dsx_fs_table[sensor->id].reg;
- err = regmap_update_bits(hw->regmap, reg->addr, reg->mask,
- ST_LSM6DSX_SHIFT_VAL(val, reg->mask));
+ data = ST_LSM6DSX_SHIFT_VAL(val, reg->mask);
+ err = st_lsm6dsx_update_bits_locked(hw, reg->addr, reg->mask, data);
if (err < 0)
return err;
@@ -463,6 +464,7 @@ static int st_lsm6dsx_set_odr(struct st_lsm6dsx_sensor *sensor, u16 odr)
{
struct st_lsm6dsx_hw *hw = sensor->hw;
const struct st_lsm6dsx_reg *reg;
+ unsigned int data;
int err;
u8 val;
@@ -471,8 +473,8 @@ static int st_lsm6dsx_set_odr(struct st_lsm6dsx_sensor *sensor, u16 odr)
return err;
reg = &st_lsm6dsx_odr_table[sensor->id].reg;
- return regmap_update_bits(hw->regmap, reg->addr, reg->mask,
- ST_LSM6DSX_SHIFT_VAL(val, reg->mask));
+ data = ST_LSM6DSX_SHIFT_VAL(val, reg->mask);
+ return st_lsm6dsx_update_bits_locked(hw, reg->addr, reg->mask, data);
}
int st_lsm6dsx_sensor_enable(struct st_lsm6dsx_sensor *sensor)
@@ -492,11 +494,12 @@ int st_lsm6dsx_sensor_disable(struct st_lsm6dsx_sensor *sensor)
{
struct st_lsm6dsx_hw *hw = sensor->hw;
const struct st_lsm6dsx_reg *reg;
+ unsigned int data;
int err;
reg = &st_lsm6dsx_odr_table[sensor->id].reg;
- err = regmap_update_bits(hw->regmap, reg->addr, reg->mask,
- ST_LSM6DSX_SHIFT_VAL(0, reg->mask));
+ data = ST_LSM6DSX_SHIFT_VAL(0, reg->mask);
+ err = st_lsm6dsx_update_bits_locked(hw, reg->addr, reg->mask, data);
if (err < 0)
return err;
@@ -519,7 +522,7 @@ static int st_lsm6dsx_read_oneshot(struct st_lsm6dsx_sensor *sensor,
delay = 1000000 / sensor->odr;
usleep_range(delay, 2 * delay);
- err = regmap_bulk_read(hw->regmap, addr, &data, sizeof(data));
+ err = st_lsm6dsx_read_locked(hw, addr, &data, sizeof(data));
if (err < 0)
return err;
@@ -865,6 +868,7 @@ int st_lsm6dsx_probe(struct device *dev, int irq, int hw_id, const char *name,
mutex_init(&hw->fifo_lock);
mutex_init(&hw->conf_lock);
+ mutex_init(&hw->page_lock);
hw->buff = devm_kzalloc(dev, ST_LSM6DSX_BUFF_SIZE, GFP_KERNEL);
if (!hw->buff)
@@ -909,6 +913,7 @@ static int __maybe_unused st_lsm6dsx_suspend(struct device *dev)
struct st_lsm6dsx_hw *hw = dev_get_drvdata(dev);
struct st_lsm6dsx_sensor *sensor;
const struct st_lsm6dsx_reg *reg;
+ unsigned int data;
int i, err = 0;
for (i = 0; i < ST_LSM6DSX_ID_MAX; i++) {
@@ -917,8 +922,9 @@ static int __maybe_unused st_lsm6dsx_suspend(struct device *dev)
continue;
reg = &st_lsm6dsx_odr_table[sensor->id].reg;
- err = regmap_update_bits(hw->regmap, reg->addr, reg->mask,
- ST_LSM6DSX_SHIFT_VAL(0, reg->mask));
+ data = ST_LSM6DSX_SHIFT_VAL(0, reg->mask);
+ err = st_lsm6dsx_update_bits_locked(hw, reg->addr, reg->mask,
+ data);
if (err < 0)
return err;
}
--
2.19.1
