From: Tiberiu Breana Date: Wed, 24 Jun 2015 14:01:48 +0000 (+0300) Subject: iio: accel: Add buffer mode for Sensortek STK8312 X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=95c12bba51c37359073b34f1a56fe396bd33d3cf;p=linux-beck.git iio: accel: Add buffer mode for Sensortek STK8312 Added triggered buffer mode support for the STK8312 accelerometer. Additional changes: - set_mode now sets operation mode directly, no longer masking the register's previous value - 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 Signed-off-by: Jonathan Cameron --- diff --git a/drivers/iio/accel/stk8312.c b/drivers/iio/accel/stk8312.c index d211d9f3975b..be58d66d5d33 100644 --- a/drivers/iio/accel/stk8312.c +++ b/drivers/iio/accel/stk8312.c @@ -11,16 +11,23 @@ */ #include +#include #include +#include #include #include #include +#include #include #include +#include +#include +#include #define STK8312_REG_XOUT 0x00 #define STK8312_REG_YOUT 0x01 #define STK8312_REG_ZOUT 0x02 +#define STK8312_REG_INTSU 0x06 #define STK8312_REG_MODE 0x07 #define STK8312_REG_STH 0x13 #define STK8312_REG_RESET 0x20 @@ -29,14 +36,19 @@ #define STK8312_REG_OTPDATA 0x3E #define STK8312_REG_OTPCTRL 0x3F -#define STK8312_MODE_ACTIVE 1 -#define STK8312_MODE_STANDBY 0 -#define STK8312_MODE_MASK 0x01 +#define STK8312_MODE_ACTIVE 0x01 +#define STK8312_MODE_STANDBY 0x00 +#define STK8312_DREADY_BIT 0x10 +#define STK8312_INT_MODE 0xC0 #define STK8312_RNG_MASK 0xC0 #define STK8312_RNG_SHIFT 6 #define STK8312_READ_RETRIES 16 +#define STK8312_ALL_CHANNEL_MASK 7 +#define STK8312_ALL_CHANNEL_SIZE 3 #define STK8312_DRIVER_NAME "stk8312" +#define STK8312_GPIO "stk8312_gpio" +#define STK8312_IRQ_NAME "stk8312_event" /* * The accelerometer has two measurement ranges: @@ -53,19 +65,27 @@ static const int stk8312_scale_table[][2] = { {0, 461600}, {1, 231100} }; -#define STK8312_ACCEL_CHANNEL(reg, axis) { \ +#define STK8312_ACCEL_CHANNEL(index, reg, axis) { \ .type = IIO_ACCEL, \ .address = reg, \ .modified = 1, \ .channel2 = IIO_MOD_##axis, \ .info_mask_separate = BIT(IIO_CHAN_INFO_RAW), \ .info_mask_shared_by_type = BIT(IIO_CHAN_INFO_SCALE), \ + .scan_index = index, \ + .scan_type = { \ + .sign = 's', \ + .realbits = 8, \ + .storagebits = 8, \ + .endianness = IIO_CPU, \ + }, \ } static const struct iio_chan_spec stk8312_channels[] = { - STK8312_ACCEL_CHANNEL(STK8312_REG_XOUT, X), - STK8312_ACCEL_CHANNEL(STK8312_REG_YOUT, Y), - STK8312_ACCEL_CHANNEL(STK8312_REG_ZOUT, Z), + STK8312_ACCEL_CHANNEL(0, STK8312_REG_XOUT, X), + STK8312_ACCEL_CHANNEL(1, STK8312_REG_YOUT, Y), + STK8312_ACCEL_CHANNEL(2, STK8312_REG_ZOUT, Z), + IIO_CHAN_SOFT_TIMESTAMP(3), }; struct stk8312_data { @@ -73,6 +93,9 @@ struct stk8312_data { struct mutex lock; int range; u8 mode; + struct iio_trigger *dready_trig; + bool dready_trigger_on; + s8 buffer[16]; /* 3x8-bit channels + 5x8 padding + 64-bit timestamp */ }; static IIO_CONST_ATTR(in_accel_scale_available, STK8312_SCALE_AVAIL); @@ -130,31 +153,19 @@ exit_err: static int stk8312_set_mode(struct stk8312_data *data, u8 mode) { int ret; - u8 masked_reg; struct i2c_client *client = data->client; - if (mode > 1) - return -EINVAL; - else if (mode == data->mode) + if (mode == data->mode) return 0; - ret = i2c_smbus_read_byte_data(client, STK8312_REG_MODE); - if (ret < 0) { - dev_err(&client->dev, "failed to change sensor mode\n"); - return ret; - } - masked_reg = ret & (~STK8312_MODE_MASK); - masked_reg |= mode; - - ret = i2c_smbus_write_byte_data(client, - STK8312_REG_MODE, masked_reg); + ret = i2c_smbus_write_byte_data(client, STK8312_REG_MODE, mode); if (ret < 0) { dev_err(&client->dev, "failed to change sensor mode\n"); return ret; } data->mode = mode; - if (mode == STK8312_MODE_ACTIVE) { + if (mode & STK8312_MODE_ACTIVE) { /* Need to run OTP sequence before entering active mode */ usleep_range(1000, 5000); ret = stk8312_otp_init(data); @@ -163,6 +174,52 @@ static int stk8312_set_mode(struct stk8312_data *data, u8 mode) return ret; } +static int stk8312_set_interrupts(struct stk8312_data *data, u8 int_mask) +{ + int ret; + u8 mode; + struct i2c_client *client = data->client; + + mode = data->mode; + /* We need to go in standby mode to modify registers */ + ret = stk8312_set_mode(data, STK8312_MODE_STANDBY); + if (ret < 0) + return ret; + + ret = i2c_smbus_write_byte_data(client, STK8312_REG_INTSU, int_mask); + if (ret < 0) + dev_err(&client->dev, "failed to set interrupts\n"); + + return stk8312_set_mode(data, mode); +} + +static int stk8312_data_rdy_trigger_set_state(struct iio_trigger *trig, + bool state) +{ + struct iio_dev *indio_dev = iio_trigger_get_drvdata(trig); + struct stk8312_data *data = iio_priv(indio_dev); + int ret; + + if (state) + ret = stk8312_set_interrupts(data, STK8312_DREADY_BIT); + else + ret = stk8312_set_interrupts(data, 0x00); + + if (ret < 0) { + dev_err(&data->client->dev, "failed to set trigger state\n"); + return ret; + } + + data->dready_trigger_on = state; + + return ret; +} + +static const struct iio_trigger_ops stk8312_trigger_ops = { + .set_trigger_state = stk8312_data_rdy_trigger_set_state, + .owner = THIS_MODULE, +}; + static int stk8312_set_range(struct stk8312_data *data, u8 range) { int ret; @@ -208,12 +265,10 @@ static int stk8312_read_accel(struct stk8312_data *data, u8 address) return -EINVAL; ret = i2c_smbus_read_byte_data(client, address); - if (ret < 0) { + if (ret < 0) dev_err(&client->dev, "register read failed\n"); - return ret; - } - return sign_extend32(ret, 7); + return ret; } static int stk8312_read_raw(struct iio_dev *indio_dev, @@ -221,14 +276,27 @@ static int stk8312_read_raw(struct iio_dev *indio_dev, int *val, int *val2, long mask) { struct stk8312_data *data = iio_priv(indio_dev); - - if (chan->type != IIO_ACCEL) - return -EINVAL; + int ret; switch (mask) { case IIO_CHAN_INFO_RAW: + if (iio_buffer_enabled(indio_dev)) + return -EBUSY; mutex_lock(&data->lock); - *val = stk8312_read_accel(data, chan->address); + ret = stk8312_set_mode(data, data->mode | STK8312_MODE_ACTIVE); + if (ret < 0) { + mutex_unlock(&data->lock); + return -EINVAL; + } + ret = stk8312_read_accel(data, chan->address); + if (ret < 0) { + stk8312_set_mode(data, + data->mode & (~STK8312_MODE_ACTIVE)); + mutex_unlock(&data->lock); + return -EINVAL; + } + *val = sign_extend32(ret, 7); + stk8312_set_mode(data, data->mode & (~STK8312_MODE_ACTIVE)); mutex_unlock(&data->lock); return IIO_VAL_INT; case IIO_CHAN_INFO_SCALE: @@ -277,6 +345,109 @@ static const struct iio_info stk8312_info = { .attrs = &stk8312_attribute_group, }; +static irqreturn_t stk8312_trigger_handler(int irq, void *p) +{ + struct iio_poll_func *pf = p; + struct iio_dev *indio_dev = pf->indio_dev; + struct stk8312_data *data = iio_priv(indio_dev); + int bit, ret, i = 0; + u8 buffer[STK8312_ALL_CHANNEL_SIZE]; + + mutex_lock(&data->lock); + /* + * Do a bulk read if all channels are requested, + * from 0x00 (XOUT) to 0x02 (ZOUT) + */ + if (*(indio_dev->active_scan_mask) == STK8312_ALL_CHANNEL_MASK) { + ret = i2c_smbus_read_i2c_block_data(data->client, + STK8312_REG_XOUT, + STK8312_ALL_CHANNEL_SIZE, + buffer); + if (ret < STK8312_ALL_CHANNEL_SIZE) { + dev_err(&data->client->dev, "register read failed\n"); + mutex_unlock(&data->lock); + goto err; + } + data->buffer[0] = buffer[0]; + data->buffer[1] = buffer[1]; + data->buffer[2] = buffer[2]; + } else { + for_each_set_bit(bit, indio_dev->active_scan_mask, + indio_dev->masklength) { + ret = stk8312_read_accel(data, bit); + if (ret < 0) { + mutex_unlock(&data->lock); + goto err; + } + data->buffer[i++] = ret; + } + } + mutex_unlock(&data->lock); + + iio_push_to_buffers_with_timestamp(indio_dev, data->buffer, + pf->timestamp); +err: + iio_trigger_notify_done(indio_dev->trig); + + return IRQ_HANDLED; +} + +static irqreturn_t stk8312_data_rdy_trig_poll(int irq, void *private) +{ + struct iio_dev *indio_dev = private; + struct stk8312_data *data = iio_priv(indio_dev); + + if (data->dready_trigger_on) + iio_trigger_poll(data->dready_trig); + + return IRQ_HANDLED; +} + +static int stk8312_buffer_preenable(struct iio_dev *indio_dev) +{ + struct stk8312_data *data = iio_priv(indio_dev); + + return stk8312_set_mode(data, data->mode | STK8312_MODE_ACTIVE); +} + +static int stk8312_buffer_postdisable(struct iio_dev *indio_dev) +{ + struct stk8312_data *data = iio_priv(indio_dev); + + return stk8312_set_mode(data, data->mode & (~STK8312_MODE_ACTIVE)); +} + +static const struct iio_buffer_setup_ops stk8312_buffer_setup_ops = { + .preenable = stk8312_buffer_preenable, + .postenable = iio_triggered_buffer_postenable, + .predisable = iio_triggered_buffer_predisable, + .postdisable = stk8312_buffer_postdisable, +}; + +static int stk8312_gpio_probe(struct i2c_client *client) +{ + struct device *dev; + struct gpio_desc *gpio; + int ret; + + if (!client) + return -EINVAL; + + dev = &client->dev; + + /* data ready gpio interrupt pin */ + gpio = devm_gpiod_get_index(dev, STK8312_GPIO, 0, GPIOD_IN); + if (IS_ERR(gpio)) { + dev_err(dev, "acpi gpio get index failed\n"); + return PTR_ERR(gpio); + } + + ret = gpiod_to_irq(gpio); + dev_dbg(dev, "GPIO resource, no:%d irq:%d\n", desc_to_gpio(gpio), ret); + + return ret; +} + static int stk8312_probe(struct i2c_client *client, const struct i2c_device_id *id) { @@ -312,26 +483,85 @@ static int stk8312_probe(struct i2c_client *client, if (ret < 0) return ret; - ret = stk8312_set_mode(data, STK8312_MODE_ACTIVE); + ret = stk8312_set_mode(data, STK8312_INT_MODE | STK8312_MODE_ACTIVE); if (ret < 0) return ret; + if (client->irq < 0) + client->irq = stk8312_gpio_probe(client); + + if (client->irq >= 0) { + ret = devm_request_threaded_irq(&client->dev, client->irq, + stk8312_data_rdy_trig_poll, + NULL, + IRQF_TRIGGER_RISING | + IRQF_ONESHOT, + STK8312_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 = &stk8312_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, + stk8312_trigger_handler, + &stk8312_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"); - stk8312_set_mode(data, STK8312_MODE_STANDBY); + 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: + stk8312_set_mode(data, STK8312_MODE_STANDBY); + return ret; } static int stk8312_remove(struct i2c_client *client) { struct iio_dev *indio_dev = i2c_get_clientdata(client); + struct stk8312_data *data = iio_priv(indio_dev); iio_device_unregister(indio_dev); + iio_triggered_buffer_cleanup(indio_dev); - return stk8312_set_mode(iio_priv(indio_dev), STK8312_MODE_STANDBY); + if (data->dready_trig) + iio_trigger_unregister(data->dready_trig); + + return stk8312_set_mode(data, STK8312_MODE_STANDBY); } #ifdef CONFIG_PM_SLEEP @@ -341,7 +571,7 @@ static int stk8312_suspend(struct device *dev) data = iio_priv(i2c_get_clientdata(to_i2c_client(dev))); - return stk8312_set_mode(data, STK8312_MODE_STANDBY); + return stk8312_set_mode(data, data->mode & (~STK8312_MODE_ACTIVE)); } static int stk8312_resume(struct device *dev) @@ -350,7 +580,7 @@ static int stk8312_resume(struct device *dev) data = iio_priv(i2c_get_clientdata(to_i2c_client(dev))); - return stk8312_set_mode(data, STK8312_MODE_ACTIVE); + return stk8312_set_mode(data, data->mode | STK8312_MODE_ACTIVE); } static SIMPLE_DEV_PM_OPS(stk8312_pm_ops, stk8312_suspend, stk8312_resume);