diff options
Diffstat (limited to 'drivers/iio/adc/ad_sigma_delta.c')
| -rw-r--r-- | drivers/iio/adc/ad_sigma_delta.c | 282 |
1 files changed, 179 insertions, 103 deletions
diff --git a/drivers/iio/adc/ad_sigma_delta.c b/drivers/iio/adc/ad_sigma_delta.c index 8115b6de1d6c..261a9a6b45e1 100644 --- a/drivers/iio/adc/ad_sigma_delta.c +++ b/drivers/iio/adc/ad_sigma_delta.c @@ -6,6 +6,7 @@ * Author: Lars-Peter Clausen <lars@metafoo.de> */ +#include <linux/align.h> #include <linux/interrupt.h> #include <linux/device.h> #include <linux/kernel.h> @@ -42,7 +43,7 @@ void ad_sd_set_comm(struct ad_sigma_delta *sigma_delta, uint8_t comm) * to select the channel */ sigma_delta->comm = comm & AD_SD_COMM_CHAN_MASK; } -EXPORT_SYMBOL_GPL(ad_sd_set_comm); +EXPORT_SYMBOL_NS_GPL(ad_sd_set_comm, IIO_AD_SIGMA_DELTA); /** * ad_sd_write_reg() - Write a register @@ -57,7 +58,7 @@ EXPORT_SYMBOL_GPL(ad_sd_set_comm); int ad_sd_write_reg(struct ad_sigma_delta *sigma_delta, unsigned int reg, unsigned int size, unsigned int val) { - uint8_t *data = sigma_delta->data; + uint8_t *data = sigma_delta->tx_buf; struct spi_transfer t = { .tx_buf = data, .len = size + 1, @@ -70,9 +71,7 @@ int ad_sd_write_reg(struct ad_sigma_delta *sigma_delta, unsigned int reg, switch (size) { case 3: - data[1] = val >> 16; - data[2] = val >> 8; - data[3] = val; + put_unaligned_be24(val, &data[1]); break; case 2: put_unaligned_be16(val, &data[1]); @@ -96,12 +95,12 @@ int ad_sd_write_reg(struct ad_sigma_delta *sigma_delta, unsigned int reg, return ret; } -EXPORT_SYMBOL_GPL(ad_sd_write_reg); +EXPORT_SYMBOL_NS_GPL(ad_sd_write_reg, IIO_AD_SIGMA_DELTA); static int ad_sd_read_reg_raw(struct ad_sigma_delta *sigma_delta, unsigned int reg, unsigned int size, uint8_t *val) { - uint8_t *data = sigma_delta->data; + uint8_t *data = sigma_delta->tx_buf; int ret; struct spi_transfer t[] = { { @@ -148,24 +147,22 @@ int ad_sd_read_reg(struct ad_sigma_delta *sigma_delta, { int ret; - ret = ad_sd_read_reg_raw(sigma_delta, reg, size, sigma_delta->data); + ret = ad_sd_read_reg_raw(sigma_delta, reg, size, sigma_delta->rx_buf); if (ret < 0) goto out; switch (size) { case 4: - *val = get_unaligned_be32(sigma_delta->data); + *val = get_unaligned_be32(sigma_delta->rx_buf); break; case 3: - *val = (sigma_delta->data[0] << 16) | - (sigma_delta->data[1] << 8) | - sigma_delta->data[2]; + *val = get_unaligned_be24(sigma_delta->rx_buf); break; case 2: - *val = get_unaligned_be16(sigma_delta->data); + *val = get_unaligned_be16(sigma_delta->rx_buf); break; case 1: - *val = sigma_delta->data[0]; + *val = sigma_delta->rx_buf[0]; break; default: ret = -EINVAL; @@ -175,7 +172,7 @@ int ad_sd_read_reg(struct ad_sigma_delta *sigma_delta, out: return ret; } -EXPORT_SYMBOL_GPL(ad_sd_read_reg); +EXPORT_SYMBOL_NS_GPL(ad_sd_read_reg, IIO_AD_SIGMA_DELTA); /** * ad_sd_reset() - Reset the serial interface @@ -203,7 +200,7 @@ int ad_sd_reset(struct ad_sigma_delta *sigma_delta, return ret; } -EXPORT_SYMBOL_GPL(ad_sd_reset); +EXPORT_SYMBOL_NS_GPL(ad_sd_reset, IIO_AD_SIGMA_DELTA); int ad_sd_calibrate(struct ad_sigma_delta *sigma_delta, unsigned int mode, unsigned int channel) @@ -242,7 +239,7 @@ out: return ret; } -EXPORT_SYMBOL_GPL(ad_sd_calibrate); +EXPORT_SYMBOL_NS_GPL(ad_sd_calibrate, IIO_AD_SIGMA_DELTA); /** * ad_sd_calibrate_all() - Performs channel calibration @@ -266,7 +263,7 @@ int ad_sd_calibrate_all(struct ad_sigma_delta *sigma_delta, return 0; } -EXPORT_SYMBOL_GPL(ad_sd_calibrate_all); +EXPORT_SYMBOL_NS_GPL(ad_sd_calibrate_all, IIO_AD_SIGMA_DELTA); /** * ad_sigma_delta_single_conversion() - Performs a single data conversion @@ -341,24 +338,54 @@ out: return IIO_VAL_INT; } -EXPORT_SYMBOL_GPL(ad_sigma_delta_single_conversion); +EXPORT_SYMBOL_NS_GPL(ad_sigma_delta_single_conversion, IIO_AD_SIGMA_DELTA); static int ad_sd_buffer_postenable(struct iio_dev *indio_dev) { struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); + unsigned int i, slot, samples_buf_size; unsigned int channel; + uint8_t *samples_buf; int ret; - ret = iio_triggered_buffer_postenable(indio_dev); - if (ret < 0) - return ret; + if (sigma_delta->num_slots == 1) { + channel = find_first_bit(indio_dev->active_scan_mask, + indio_dev->masklength); + ret = ad_sigma_delta_set_channel(sigma_delta, + indio_dev->channels[channel].address); + if (ret) + return ret; + slot = 1; + } else { + /* + * At this point update_scan_mode already enabled the required channels. + * For sigma-delta sequencer drivers with multiple slots, an update_scan_mode + * implementation is mandatory. + */ + slot = 0; + for_each_set_bit(i, indio_dev->active_scan_mask, indio_dev->masklength) { + sigma_delta->slots[slot] = indio_dev->channels[i].address; + slot++; + } + } - channel = find_first_bit(indio_dev->active_scan_mask, - indio_dev->masklength); - ret = ad_sigma_delta_set_channel(sigma_delta, - indio_dev->channels[channel].address); - if (ret) - return ret; + sigma_delta->active_slots = slot; + sigma_delta->current_slot = 0; + + if (sigma_delta->active_slots > 1) { + ret = ad_sigma_delta_append_status(sigma_delta, true); + if (ret) + return ret; + } + + samples_buf_size = ALIGN(slot * indio_dev->channels[0].scan_type.storagebits, 8); + samples_buf_size += sizeof(int64_t); + samples_buf = devm_krealloc(&sigma_delta->spi->dev, sigma_delta->samples_buf, + samples_buf_size, GFP_KERNEL); + if (!samples_buf) + return -ENOMEM; + + sigma_delta->samples_buf = samples_buf; spi_bus_lock(sigma_delta->spi->master); sigma_delta->bus_locked = true; @@ -394,6 +421,10 @@ static int ad_sd_buffer_postdisable(struct iio_dev *indio_dev) sigma_delta->keep_cs_asserted = false; ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_IDLE); + if (sigma_delta->status_appended) + ad_sigma_delta_append_status(sigma_delta, false); + + ad_sigma_delta_disable_all(sigma_delta); sigma_delta->bus_locked = false; return spi_bus_unlock(sigma_delta->spi->master); } @@ -403,12 +434,13 @@ static irqreturn_t ad_sd_trigger_handler(int irq, void *p) struct iio_poll_func *pf = p; struct iio_dev *indio_dev = pf->indio_dev; struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); + uint8_t *data = sigma_delta->rx_buf; + unsigned int transfer_size; + unsigned int sample_size; + unsigned int sample_pos; + unsigned int status_pos; unsigned int reg_size; unsigned int data_reg; - uint8_t data[16]; - int ret; - - memset(data, 0x00, 16); reg_size = indio_dev->channels[0].scan_type.realbits + indio_dev->channels[0].scan_type.shift; @@ -419,23 +451,69 @@ static irqreturn_t ad_sd_trigger_handler(int irq, void *p) else data_reg = AD_SD_REG_DATA; + /* Status word will be appended to the sample during transfer */ + if (sigma_delta->status_appended) + transfer_size = reg_size + 1; + else + transfer_size = reg_size; + switch (reg_size) { case 4: case 2: case 1: - ret = ad_sd_read_reg_raw(sigma_delta, data_reg, reg_size, - &data[0]); + status_pos = reg_size; + ad_sd_read_reg_raw(sigma_delta, data_reg, transfer_size, &data[0]); break; case 3: + /* + * Data array after transfer will look like (if status is appended): + * data[] = { [0][sample][sample][sample][status] } + * Keeping the first byte 0 shifts the status postion by 1 byte to the right. + */ + status_pos = reg_size + 1; + /* We store 24 bit samples in a 32 bit word. Keep the upper * byte set to zero. */ - ret = ad_sd_read_reg_raw(sigma_delta, data_reg, reg_size, - &data[1]); + ad_sd_read_reg_raw(sigma_delta, data_reg, transfer_size, &data[1]); break; } - iio_push_to_buffers_with_timestamp(indio_dev, data, pf->timestamp); + /* + * For devices sampling only one channel at + * once, there is no need for sample number tracking. + */ + if (sigma_delta->active_slots == 1) { + iio_push_to_buffers_with_timestamp(indio_dev, data, pf->timestamp); + goto irq_handled; + } + + if (sigma_delta->status_appended) { + u8 converted_channel; + + converted_channel = data[status_pos] & sigma_delta->info->status_ch_mask; + if (converted_channel != sigma_delta->slots[sigma_delta->current_slot]) { + /* + * Desync occurred during continuous sampling of multiple channels. + * Drop this incomplete sample and start from first channel again. + */ + + sigma_delta->current_slot = 0; + goto irq_handled; + } + } + + sample_size = indio_dev->channels[0].scan_type.storagebits / 8; + sample_pos = sample_size * sigma_delta->current_slot; + memcpy(&sigma_delta->samples_buf[sample_pos], data, sample_size); + sigma_delta->current_slot++; + if (sigma_delta->current_slot == sigma_delta->active_slots) { + sigma_delta->current_slot = 0; + iio_push_to_buffers_with_timestamp(indio_dev, sigma_delta->samples_buf, + pf->timestamp); + } + +irq_handled: iio_trigger_notify_done(indio_dev->trig); sigma_delta->irq_dis = false; enable_irq(sigma_delta->spi->irq); @@ -443,11 +521,17 @@ static irqreturn_t ad_sd_trigger_handler(int irq, void *p) return IRQ_HANDLED; } +static bool ad_sd_validate_scan_mask(struct iio_dev *indio_dev, const unsigned long *mask) +{ + struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); + + return bitmap_weight(mask, indio_dev->masklength) <= sigma_delta->num_slots; +} + static const struct iio_buffer_setup_ops ad_sd_buffer_setup_ops = { .postenable = &ad_sd_buffer_postenable, - .predisable = &iio_triggered_buffer_predisable, .postdisable = &ad_sd_buffer_postdisable, - .validate_scan_mask = &iio_validate_scan_mask_onehot, + .validate_scan_mask = &ad_sd_validate_scan_mask, }; static irqreturn_t ad_sd_data_rdy_trig_poll(int irq, void *private) @@ -479,99 +563,72 @@ int ad_sd_validate_trigger(struct iio_dev *indio_dev, struct iio_trigger *trig) return 0; } -EXPORT_SYMBOL_GPL(ad_sd_validate_trigger); - -static const struct iio_trigger_ops ad_sd_trigger_ops = { -}; +EXPORT_SYMBOL_NS_GPL(ad_sd_validate_trigger, IIO_AD_SIGMA_DELTA); -static int ad_sd_probe_trigger(struct iio_dev *indio_dev) +static int devm_ad_sd_probe_trigger(struct device *dev, struct iio_dev *indio_dev) { struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); int ret; - sigma_delta->trig = iio_trigger_alloc("%s-dev%d", indio_dev->name, - indio_dev->id); - if (sigma_delta->trig == NULL) { - ret = -ENOMEM; - goto error_ret; + if (dev != &sigma_delta->spi->dev) { + dev_err(dev, "Trigger parent should be '%s', got '%s'\n", + dev_name(dev), dev_name(&sigma_delta->spi->dev)); + return -EFAULT; } - sigma_delta->trig->ops = &ad_sd_trigger_ops; + + sigma_delta->trig = devm_iio_trigger_alloc(dev, "%s-dev%d", indio_dev->name, + iio_device_id(indio_dev)); + if (sigma_delta->trig == NULL) + return -ENOMEM; + init_completion(&sigma_delta->completion); - ret = request_irq(sigma_delta->spi->irq, - ad_sd_data_rdy_trig_poll, - sigma_delta->info->irq_flags, - indio_dev->name, - sigma_delta); + sigma_delta->irq_dis = true; + ret = devm_request_irq(dev, sigma_delta->spi->irq, + ad_sd_data_rdy_trig_poll, + sigma_delta->info->irq_flags | IRQF_NO_AUTOEN, + indio_dev->name, + sigma_delta); if (ret) - goto error_free_trig; + return ret; - if (!sigma_delta->irq_dis) { - sigma_delta->irq_dis = true; - disable_irq_nosync(sigma_delta->spi->irq); - } - sigma_delta->trig->dev.parent = &sigma_delta->spi->dev; iio_trigger_set_drvdata(sigma_delta->trig, sigma_delta); - ret = iio_trigger_register(sigma_delta->trig); + ret = devm_iio_trigger_register(dev, sigma_delta->trig); if (ret) - goto error_free_irq; + return ret; /* select default trigger */ indio_dev->trig = iio_trigger_get(sigma_delta->trig); return 0; - -error_free_irq: - free_irq(sigma_delta->spi->irq, sigma_delta); -error_free_trig: - iio_trigger_free(sigma_delta->trig); -error_ret: - return ret; -} - -static void ad_sd_remove_trigger(struct iio_dev *indio_dev) -{ - struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); - - iio_trigger_unregister(sigma_delta->trig); - free_irq(sigma_delta->spi->irq, sigma_delta); - iio_trigger_free(sigma_delta->trig); } /** - * ad_sd_setup_buffer_and_trigger() - + * devm_ad_sd_setup_buffer_and_trigger() - Device-managed buffer & trigger setup + * @dev: Device object to which to bind the life-time of the resources attached * @indio_dev: The IIO device */ -int ad_sd_setup_buffer_and_trigger(struct iio_dev *indio_dev) +int devm_ad_sd_setup_buffer_and_trigger(struct device *dev, struct iio_dev *indio_dev) { + struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); int ret; - ret = iio_triggered_buffer_setup(indio_dev, &iio_pollfunc_store_time, - &ad_sd_trigger_handler, &ad_sd_buffer_setup_ops); + sigma_delta->slots = devm_kcalloc(dev, sigma_delta->num_slots, + sizeof(*sigma_delta->slots), GFP_KERNEL); + if (!sigma_delta->slots) + return -ENOMEM; + + ret = devm_iio_triggered_buffer_setup(dev, indio_dev, + &iio_pollfunc_store_time, + &ad_sd_trigger_handler, + &ad_sd_buffer_setup_ops); if (ret) return ret; - ret = ad_sd_probe_trigger(indio_dev); - if (ret) { - iio_triggered_buffer_cleanup(indio_dev); - return ret; - } - - return 0; + return devm_ad_sd_probe_trigger(dev, indio_dev); } -EXPORT_SYMBOL_GPL(ad_sd_setup_buffer_and_trigger); - -/** - * ad_sd_cleanup_buffer_and_trigger() - - * @indio_dev: The IIO device - */ -void ad_sd_cleanup_buffer_and_trigger(struct iio_dev *indio_dev) -{ - ad_sd_remove_trigger(indio_dev); - iio_triggered_buffer_cleanup(indio_dev); -} -EXPORT_SYMBOL_GPL(ad_sd_cleanup_buffer_and_trigger); +EXPORT_SYMBOL_NS_GPL(devm_ad_sd_setup_buffer_and_trigger, IIO_AD_SIGMA_DELTA); /** * ad_sd_init() - Initializes a ad_sigma_delta struct @@ -588,11 +645,30 @@ int ad_sd_init(struct ad_sigma_delta *sigma_delta, struct iio_dev *indio_dev, { sigma_delta->spi = spi; sigma_delta->info = info; + + /* If the field is unset in ad_sigma_delta_info, asume there can only be 1 slot. */ + if (!info->num_slots) + sigma_delta->num_slots = 1; + else + sigma_delta->num_slots = info->num_slots; + + if (sigma_delta->num_slots > 1) { + if (!indio_dev->info->update_scan_mode) { + dev_err(&spi->dev, "iio_dev lacks update_scan_mode().\n"); + return -EINVAL; + } + + if (!info->disable_all) { + dev_err(&spi->dev, "ad_sigma_delta_info lacks disable_all().\n"); + return -EINVAL; + } + } + iio_device_set_drvdata(indio_dev, sigma_delta); return 0; } -EXPORT_SYMBOL_GPL(ad_sd_init); +EXPORT_SYMBOL_NS_GPL(ad_sd_init, IIO_AD_SIGMA_DELTA); MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); MODULE_DESCRIPTION("Analog Devices Sigma-Delta ADCs"); |