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path: root/drivers/iio/adc/ti_am335x_adc.c
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Diffstat (limited to 'drivers/iio/adc/ti_am335x_adc.c')
-rw-r--r--drivers/iio/adc/ti_am335x_adc.c83
1 files changed, 67 insertions, 16 deletions
diff --git a/drivers/iio/adc/ti_am335x_adc.c b/drivers/iio/adc/ti_am335x_adc.c
index a0e7161f0..942320e32 100644
--- a/drivers/iio/adc/ti_am335x_adc.c
+++ b/drivers/iio/adc/ti_am335x_adc.c
@@ -37,6 +37,7 @@ struct tiadc_device {
u8 channel_step[8];
int buffer_en_ch_steps;
u16 data[8];
+ u32 open_delay[8], sample_delay[8], step_avg[8];
};
static unsigned int tiadc_readl(struct tiadc_device *adc, unsigned int reg)
@@ -85,6 +86,7 @@ static u32 get_adc_step_bit(struct tiadc_device *adc_dev, int chan)
static void tiadc_step_config(struct iio_dev *indio_dev)
{
struct tiadc_device *adc_dev = iio_priv(indio_dev);
+ struct device *dev = adc_dev->mfd_tscadc->dev;
unsigned int stepconfig;
int i, steps = 0;
@@ -98,20 +100,47 @@ static void tiadc_step_config(struct iio_dev *indio_dev)
* needs to be given to ADC to digitalize data.
*/
- if (iio_buffer_enabled(indio_dev))
- stepconfig = STEPCONFIG_AVG_16 | STEPCONFIG_FIFO1
- | STEPCONFIG_MODE_SWCNT;
- else
- stepconfig = STEPCONFIG_AVG_16 | STEPCONFIG_FIFO1;
for (i = 0; i < adc_dev->channels; i++) {
int chan;
chan = adc_dev->channel_line[i];
+
+ if (adc_dev->step_avg[i] > STEPCONFIG_AVG_16) {
+ dev_warn(dev, "chan %d step_avg truncating to %d\n",
+ chan, STEPCONFIG_AVG_16);
+ adc_dev->step_avg[i] = STEPCONFIG_AVG_16;
+ }
+
+ if (adc_dev->step_avg[i])
+ stepconfig =
+ STEPCONFIG_AVG(ffs(adc_dev->step_avg[i]) - 1) |
+ STEPCONFIG_FIFO1;
+ else
+ stepconfig = STEPCONFIG_FIFO1;
+
+ if (iio_buffer_enabled(indio_dev))
+ stepconfig |= STEPCONFIG_MODE_SWCNT;
+
tiadc_writel(adc_dev, REG_STEPCONFIG(steps),
stepconfig | STEPCONFIG_INP(chan));
+
+ if (adc_dev->open_delay[i] > STEPDELAY_OPEN_MASK) {
+ dev_warn(dev, "chan %d open delay truncating to 0x3FFFF\n",
+ chan);
+ adc_dev->open_delay[i] = STEPDELAY_OPEN_MASK;
+ }
+
+ if (adc_dev->sample_delay[i] > 0xFF) {
+ dev_warn(dev, "chan %d sample delay truncating to 0xFF\n",
+ chan);
+ adc_dev->sample_delay[i] = 0xFF;
+ }
+
tiadc_writel(adc_dev, REG_STEPDELAY(steps),
- STEPCONFIG_OPENDLY);
+ STEPDELAY_OPEN(adc_dev->open_delay[i]) |
+ STEPDELAY_SAMPLE(adc_dev->sample_delay[i]));
+
adc_dev->channel_step[i] = steps;
steps++;
}
@@ -395,16 +424,43 @@ static const struct iio_info tiadc_info = {
.driver_module = THIS_MODULE,
};
+static int tiadc_parse_dt(struct platform_device *pdev,
+ struct tiadc_device *adc_dev)
+{
+ struct device_node *node = pdev->dev.of_node;
+ struct property *prop;
+ const __be32 *cur;
+ int channels = 0;
+ u32 val;
+
+ of_property_for_each_u32(node, "ti,adc-channels", prop, cur, val) {
+ adc_dev->channel_line[channels] = val;
+
+ /* Set Default values for optional DT parameters */
+ adc_dev->open_delay[channels] = STEPCONFIG_OPENDLY;
+ adc_dev->sample_delay[channels] = STEPCONFIG_SAMPLEDLY;
+ adc_dev->step_avg[channels] = 16;
+
+ channels++;
+ }
+
+ of_property_read_u32_array(node, "ti,chan-step-avg",
+ adc_dev->step_avg, channels);
+ of_property_read_u32_array(node, "ti,chan-step-opendelay",
+ adc_dev->open_delay, channels);
+ of_property_read_u32_array(node, "ti,chan-step-sampledelay",
+ adc_dev->sample_delay, channels);
+
+ adc_dev->channels = channels;
+ return 0;
+}
+
static int tiadc_probe(struct platform_device *pdev)
{
struct iio_dev *indio_dev;
struct tiadc_device *adc_dev;
struct device_node *node = pdev->dev.of_node;
- struct property *prop;
- const __be32 *cur;
int err;
- u32 val;
- int channels = 0;
if (!node) {
dev_err(&pdev->dev, "Could not find valid DT data.\n");
@@ -420,12 +476,7 @@ static int tiadc_probe(struct platform_device *pdev)
adc_dev = iio_priv(indio_dev);
adc_dev->mfd_tscadc = ti_tscadc_dev_get(pdev);
-
- of_property_for_each_u32(node, "ti,adc-channels", prop, cur, val) {
- adc_dev->channel_line[channels] = val;
- channels++;
- }
- adc_dev->channels = channels;
+ tiadc_parse_dt(pdev, adc_dev);
indio_dev->dev.parent = &pdev->dev;
indio_dev->name = dev_name(&pdev->dev);