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/*
* Copyright (C) 2015 Samsung Electronics
* Przemyslaw Marczak <p.marczak@samsung.com>
*
* SPDX-License-Identifier: GPL-2.0+
*/
#include <common.h>
#include <errno.h>
#include <dm.h>
#include <adc.h>
#include <sandbox-adc.h>
/**
* struct sandbox_adc_priv - sandbox ADC device's operation status and data
*
* @conversion_status - conversion status: ACTIVE (started) / INACTIVE (stopped)
* @conversion_mode - conversion mode: single or multi-channel
* @active_channel - active channel number, valid for single channel mode
* data[] - channels data
*/
struct sandbox_adc_priv {
int conversion_status;
int conversion_mode;
int active_channel_mask;
unsigned int data[4];
};
int sandbox_adc_start_channel(struct udevice *dev, int channel)
{
struct sandbox_adc_priv *priv = dev_get_priv(dev);
/* Set single-channel mode */
priv->conversion_mode = SANDBOX_ADC_MODE_SINGLE_CHANNEL;
/* Select channel */
priv->active_channel_mask = 1 << channel;
/* Start conversion */
priv->conversion_status = SANDBOX_ADC_ACTIVE;
return 0;
}
int sandbox_adc_start_channels(struct udevice *dev, unsigned int channel_mask)
{
struct sandbox_adc_priv *priv = dev_get_priv(dev);
/* Set single-channel mode */
priv->conversion_mode = SANDBOX_ADC_MODE_MULTI_CHANNEL;
/* Select channel */
priv->active_channel_mask = channel_mask;
/* Start conversion */
priv->conversion_status = SANDBOX_ADC_ACTIVE;
return 0;
}
int sandbox_adc_channel_data(struct udevice *dev, int channel,
unsigned int *data)
{
struct sandbox_adc_priv *priv = dev_get_priv(dev);
/* For single-channel conversion mode, check if channel was selected */
if ((priv->conversion_mode == SANDBOX_ADC_MODE_SINGLE_CHANNEL) &&
!(priv->active_channel_mask & (1 << channel))) {
pr_err("Request for an inactive channel!");
return -EINVAL;
}
/* The conversion must be started before reading the data */
if (priv->conversion_status == SANDBOX_ADC_INACTIVE)
return -EIO;
*data = priv->data[channel];
return 0;
}
int sandbox_adc_channels_data(struct udevice *dev, unsigned int channel_mask,
struct adc_channel *channels)
{
struct sandbox_adc_priv *priv = dev_get_priv(dev);
int i;
/* Return error for single-channel conversion mode */
if (priv->conversion_mode == SANDBOX_ADC_MODE_SINGLE_CHANNEL) {
pr_err("ADC in single-channel mode!");
return -EPERM;
}
/* Check channel selection */
if (!(priv->active_channel_mask & channel_mask)) {
pr_err("Request for an inactive channel!");
return -EINVAL;
}
/* The conversion must be started before reading the data */
if (priv->conversion_status == SANDBOX_ADC_INACTIVE)
return -EIO;
for (i = 0; i < SANDBOX_ADC_CHANNELS; i++) {
if (!((channel_mask >> i) & 0x1))
continue;
channels->data = priv->data[i];
channels->id = i;
channels++;
}
return 0;
}
int sandbox_adc_stop(struct udevice *dev)
{
struct sandbox_adc_priv *priv = dev_get_priv(dev);
/* Start conversion */
priv->conversion_status = SANDBOX_ADC_INACTIVE;
return 0;
}
int sandbox_adc_probe(struct udevice *dev)
{
struct sandbox_adc_priv *priv = dev_get_priv(dev);
/* Stop conversion */
priv->conversion_status = SANDBOX_ADC_INACTIVE;
/* Set single-channel mode */
priv->conversion_mode = SANDBOX_ADC_MODE_SINGLE_CHANNEL;
/* Deselect all channels */
priv->active_channel_mask = 0;
/* Set sandbox test data */
priv->data[0] = SANDBOX_ADC_CHANNEL0_DATA;
priv->data[1] = SANDBOX_ADC_CHANNEL1_DATA;
priv->data[2] = SANDBOX_ADC_CHANNEL2_DATA;
priv->data[3] = SANDBOX_ADC_CHANNEL3_DATA;
return 0;
}
int sandbox_adc_ofdata_to_platdata(struct udevice *dev)
{
struct adc_uclass_platdata *uc_pdata = dev_get_uclass_platdata(dev);
uc_pdata->data_mask = SANDBOX_ADC_DATA_MASK;
uc_pdata->data_format = ADC_DATA_FORMAT_BIN;
uc_pdata->data_timeout_us = 0;
/* Mask available channel bits: [0:3] */
uc_pdata->channel_mask = (1 << SANDBOX_ADC_CHANNELS) - 1;
return 0;
}
static const struct adc_ops sandbox_adc_ops = {
.start_channel = sandbox_adc_start_channel,
.start_channels = sandbox_adc_start_channels,
.channel_data = sandbox_adc_channel_data,
.channels_data = sandbox_adc_channels_data,
.stop = sandbox_adc_stop,
};
static const struct udevice_id sandbox_adc_ids[] = {
{ .compatible = "sandbox,adc" },
{ }
};
U_BOOT_DRIVER(sandbox_adc) = {
.name = "sandbox-adc",
.id = UCLASS_ADC,
.of_match = sandbox_adc_ids,
.ops = &sandbox_adc_ops,
.probe = sandbox_adc_probe,
.ofdata_to_platdata = sandbox_adc_ofdata_to_platdata,
.priv_auto_alloc_size = sizeof(struct sandbox_adc_priv),
};
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