From: Lorenzo Bianconi Date: Sun, 11 Nov 2018 14:15:28 +0000 (+0100) Subject: iio: imu: st_lsm6dsx: introduce locked read/write utility routines X-Git-Tag: v5.4-rc1~1925^2~249^2~19 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=739aff87a8176c1193cc46ebce5ce6dd537501af;p=platform%2Fkernel%2Flinux-rpi.git iio: imu: st_lsm6dsx: introduce locked read/write utility routines 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 Signed-off-by: Jonathan Cameron --- diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx.h index ef73519..ec204d3 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 b5263fc..67cd36b 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); diff --git a/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c b/drivers/iio/imu/st_lsm6dsx/st_lsm6dsx_core.c index 2ad3c61..c8b993b 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; }