Add support to sama7d65 ADC. The differences are highlighted with the
compatible. The init and parsing of the temperature sensor and
calibration indexes are the main differences.
Signed-off-by: Varshini Rajendran <varshini.rajendran@microchip.com>
---
drivers/iio/adc/at91-sama5d2_adc.c | 94 ++++++++++++++++++++++++++++++
1 file changed, 94 insertions(+)
diff --git a/drivers/iio/adc/at91-sama5d2_adc.c b/drivers/iio/adc/at91-sama5d2_adc.c
index 916682e326c7..909841b84834 100644
--- a/drivers/iio/adc/at91-sama5d2_adc.c
+++ b/drivers/iio/adc/at91-sama5d2_adc.c
@@ -456,6 +456,8 @@ static const struct at91_adc_reg_layout sama7g5_layout = {
struct at91_adc_state;
static int at91_adc_temp_sensor_init(struct at91_adc_state *st,
struct device *dev);
+static int at91_sama7d65_adc_temp_sensor_init(struct at91_adc_state *st,
+ struct device *dev);
/**
* struct at91_adc_platform - at91-sama5d2 platform information struct
@@ -525,6 +527,20 @@ enum at91_adc_ts_clb_idx {
AT91_ADC_TS_CLB_IDX_MAX = 18,
};
+/**
+ * enum at91_sama7d65_adc_ts_clb_idx - calibration indexes in sama7d65 NVMEM buffer
+ * @AT91_SAMA7D65_ADC_TS_CLB_IDX_P1: index for FT1_TEMP equivalent to P1 * (10 ^ 6)
+ * @AT91_SAMA7D65_ADC_TS_CLB_IDX_P4: index for FT1_VPAT equivalent to P4
+ * @AT91_SAMA7D65_ADC_TS_CLB_IDX_P6: index for FT2_VBG equivalent to P6
+ * @AT91_SAMA7D65_ADC_TS_CLB_IDX_MAX: max index for temperature calibration packet in OTP
+ */
+enum at91_sama7d65_adc_ts_clb_idx {
+ AT91_SAMA7D65_ADC_TS_CLB_IDX_P1 = 2,
+ AT91_SAMA7D65_ADC_TS_CLB_IDX_P4 = 1,
+ AT91_SAMA7D65_ADC_TS_CLB_IDX_P6 = 4,
+ AT91_SAMA7D65_ADC_TS_CLB_IDX_MAX = 10,
+};
+
/* Temperature sensor calibration - Vtemp voltage sensitivity to temperature. */
#define AT91_ADC_TS_VTEMP_DT (2080U)
@@ -764,6 +780,31 @@ static const struct at91_adc_platform sama7g5_platform = {
.temp_init = at91_adc_temp_sensor_init,
};
+static const struct at91_adc_platform sama7d65_platform = {
+ .layout = &sama7g5_layout,
+ .adc_channels = &at91_sama7g5_adc_channels,
+#define AT91_SAMA7D65_SINGLE_CHAN_CNT 16
+#define AT91_SAMA7D65_DIFF_CHAN_CNT 8
+#define AT91_SAMA7D65_TEMP_CHAN_CNT 1
+ .nr_channels = AT91_SAMA7D65_SINGLE_CHAN_CNT +
+ AT91_SAMA7D65_DIFF_CHAN_CNT +
+ AT91_SAMA7D65_TEMP_CHAN_CNT,
+#define AT91_SAMA7D65_MAX_CHAN_IDX (AT91_SAMA7D65_SINGLE_CHAN_CNT + \
+ AT91_SAMA7D65_DIFF_CHAN_CNT + \
+ AT91_SAMA7D65_TEMP_CHAN_CNT)
+ .max_channels = ARRAY_SIZE(at91_sama7g5_adc_channels),
+ .max_index = AT91_SAMA7D65_MAX_CHAN_IDX,
+#define AT91_SAMA7G5_HW_TRIG_CNT 3
+ .hw_trig_cnt = AT91_SAMA7G5_HW_TRIG_CNT,
+ .osr_mask = GENMASK(18, 16),
+ .oversampling_avail = { 1, 4, 16, 64, 256, },
+ .oversampling_avail_no = 5,
+ .chan_realbits = 16,
+ .temp_sensor = true,
+ .temp_chan = AT91_SAMA7G5_ADC_TEMP_CHANNEL,
+ .temp_init = at91_sama7d65_adc_temp_sensor_init,
+};
+
static int at91_adc_chan_xlate(struct iio_dev *indio_dev, int chan)
{
int i;
@@ -2319,6 +2360,56 @@ static int at91_adc_temp_sensor_init(struct at91_adc_state *st,
return ret;
}
+static int at91_sama7d65_adc_temp_sensor_init(struct at91_adc_state *st,
+ struct device *dev)
+{
+ struct at91_adc_temp_sensor_clb *clb = &st->soc_info.temp_sensor_clb;
+ struct nvmem_cell *temp_calib;
+ u32 *buf = NULL;
+ size_t len;
+ int ret = 0;
+
+ if (!st->soc_info.platform->temp_sensor)
+ return 0;
+
+ /* Get the calibration data from NVMEM. */
+ temp_calib = devm_nvmem_cell_get(dev, "temperature_calib");
+ if (IS_ERR(temp_calib)) {
+ ret = PTR_ERR(temp_calib);
+ if (ret != -ENOENT)
+ dev_err(dev, "Failed to get temperature_calib cell!\n");
+ return ret;
+ }
+
+ buf = nvmem_cell_read(temp_calib, &len);
+ if (IS_ERR(buf)) {
+ dev_err(dev, "Failed to read calibration data!\n");
+ return PTR_ERR(buf);
+ }
+
+ if (len < AT91_SAMA7D65_ADC_TS_CLB_IDX_MAX * sizeof(u32) ||
+ buf[0] != AT91_TEMP_CALIB_TAG) {
+ dev_err(dev, "Invalid calibration data!\n");
+ ret = -EINVAL;
+ goto free_buf;
+ }
+
+ /* Store calibration data for later use. */
+ clb->p1 = buf[AT91_SAMA7D65_ADC_TS_CLB_IDX_P1];
+ clb->p4 = buf[AT91_SAMA7D65_ADC_TS_CLB_IDX_P4];
+ clb->p6 = buf[AT91_SAMA7D65_ADC_TS_CLB_IDX_P6];
+
+ /*
+ * We prepare here the conversion to milli from micro to avoid
+ * doing it on hotpath.
+ */
+ clb->p1 = clb->p1 / 1000;
+
+free_buf:
+ kfree(buf);
+ return ret;
+}
+
static int at91_adc_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -2633,6 +2724,9 @@ static const struct of_device_id at91_adc_dt_match[] = {
}, {
.compatible = "microchip,sama7g5-adc",
.data = (const void *)&sama7g5_platform,
+ }, {
+ .compatible = "microchip,sama7d65-adc",
+ .data = (const void *)&sama7d65_platform,
}, {
/* sentinel */
}
--
2.34.1On Mon, Aug 4, 2025 at 12:03 PM Varshini Rajendran
<varshini.rajendran@microchip.com> wrote:
>
> Add support to sama7d65 ADC. The differences are highlighted with the
> compatible. The init and parsing of the temperature sensor and
> calibration indexes are the main differences.
...
> +static int at91_sama7d65_adc_temp_sensor_init(struct at91_adc_state *st,
> + struct device *dev);
Again, please try to avoid forward declarations. They make code harder
to maintain.
...
> +enum at91_sama7d65_adc_ts_clb_idx {
> + AT91_SAMA7D65_ADC_TS_CLB_IDX_P1 = 2,
> + AT91_SAMA7D65_ADC_TS_CLB_IDX_P4 = 1,
> + AT91_SAMA7D65_ADC_TS_CLB_IDX_P6 = 4,
> + AT91_SAMA7D65_ADC_TS_CLB_IDX_MAX = 10,
MAX and trailing comma are odd when they go together.
> +};
...
> +static const struct at91_adc_platform sama7d65_platform = {
> + .layout = &sama7g5_layout,
> + .adc_channels = &at91_sama7g5_adc_channels,
> +#define AT91_SAMA7D65_SINGLE_CHAN_CNT 16
> +#define AT91_SAMA7D65_DIFF_CHAN_CNT 8
> +#define AT91_SAMA7D65_TEMP_CHAN_CNT 1
> + .nr_channels = AT91_SAMA7D65_SINGLE_CHAN_CNT +
> + AT91_SAMA7D65_DIFF_CHAN_CNT +
> + AT91_SAMA7D65_TEMP_CHAN_CNT,
> +#define AT91_SAMA7D65_MAX_CHAN_IDX (AT91_SAMA7D65_SINGLE_CHAN_CNT + \
> + AT91_SAMA7D65_DIFF_CHAN_CNT + \
> + AT91_SAMA7D65_TEMP_CHAN_CNT)
> + .max_channels = ARRAY_SIZE(at91_sama7g5_adc_channels),
> + .max_index = AT91_SAMA7D65_MAX_CHAN_IDX,
> +#define AT91_SAMA7G5_HW_TRIG_CNT 3
> + .hw_trig_cnt = AT91_SAMA7G5_HW_TRIG_CNT,
> + .osr_mask = GENMASK(18, 16),
> + .oversampling_avail = { 1, 4, 16, 64, 256, },
> + .oversampling_avail_no = 5,
> + .chan_realbits = 16,
> + .temp_sensor = true,
> + .temp_chan = AT91_SAMA7G5_ADC_TEMP_CHANNEL,
> + .temp_init = at91_sama7d65_adc_temp_sensor_init,
> +};
It's harder to read the static assignment interleaved by the sparse
definitions. Can't you group definitions followed by the initialiser?
...
> +static int at91_sama7d65_adc_temp_sensor_init(struct at91_adc_state *st,
> + struct device *dev)
> +{
> + struct at91_adc_temp_sensor_clb *clb = &st->soc_info.temp_sensor_clb;
> + struct nvmem_cell *temp_calib;
> + u32 *buf = NULL;
What for this NULL initialiser?
> + size_t len;
> + int ret = 0;
This initialisation can be avoided (see below how).
> + if (!st->soc_info.platform->temp_sensor)
> + return 0;
> +
> + /* Get the calibration data from NVMEM. */
> + temp_calib = devm_nvmem_cell_get(dev, "temperature_calib");
> + if (IS_ERR(temp_calib)) {
> + ret = PTR_ERR(temp_calib);
> + if (ret != -ENOENT)
> + dev_err(dev, "Failed to get temperature_calib cell!\n");
> + return ret;
> + }
> +
> + buf = nvmem_cell_read(temp_calib, &len);
> + if (IS_ERR(buf)) {
> + dev_err(dev, "Failed to read calibration data!\n");
> + return PTR_ERR(buf);
> + }
...
> + /*
> + * We prepare here the conversion to milli from micro to avoid
Here we prepare the...
> + * doing it on hotpath.
> + */
...
> +free_buf:
> + kfree(buf);
> + return ret;
Can't use cleanup.h? I.e. __free().
--
With Best Regards,
Andy Shevchenko
On Mon, 4 Aug 2025 15:32:13 +0530
Varshini Rajendran <varshini.rajendran@microchip.com> wrote:
> Add support to sama7d65 ADC. The differences are highlighted with the
> compatible. The init and parsing of the temperature sensor and
> calibration indexes are the main differences.
>
> Signed-off-by: Varshini Rajendran <varshini.rajendran@microchip.com>
...
> static int at91_adc_chan_xlate(struct iio_dev *indio_dev, int chan)
> {
> int i;
> @@ -2319,6 +2360,56 @@ static int at91_adc_temp_sensor_init(struct at91_adc_state *st,
> return ret;
> }
>
> +static int at91_sama7d65_adc_temp_sensor_init(struct at91_adc_state *st,
> + struct device *dev)
> +{
> + struct at91_adc_temp_sensor_clb *clb = &st->soc_info.temp_sensor_clb;
> + struct nvmem_cell *temp_calib;
> + u32 *buf = NULL;
As per earlier comment and I see Andy raised it as well. __free()
magic dust is useful here.
> + size_t len;
> + int ret = 0;
> +
> + if (!st->soc_info.platform->temp_sensor)
> + return 0;
> +
> + /* Get the calibration data from NVMEM. */
> + temp_calib = devm_nvmem_cell_get(dev, "temperature_calib");
> + if (IS_ERR(temp_calib)) {
> + ret = PTR_ERR(temp_calib);
> + if (ret != -ENOENT)
> + dev_err(dev, "Failed to get temperature_calib cell!\n");
> + return ret;
> + }
> +
> + buf = nvmem_cell_read(temp_calib, &len);
> + if (IS_ERR(buf)) {
> + dev_err(dev, "Failed to read calibration data!\n");
> + return PTR_ERR(buf);
> + }
> +
> + if (len < AT91_SAMA7D65_ADC_TS_CLB_IDX_MAX * sizeof(u32) ||
> + buf[0] != AT91_TEMP_CALIB_TAG) {
> + dev_err(dev, "Invalid calibration data!\n");
> + ret = -EINVAL;
> + goto free_buf;
> + }
> +
> + /* Store calibration data for later use. */
> + clb->p1 = buf[AT91_SAMA7D65_ADC_TS_CLB_IDX_P1];
> + clb->p4 = buf[AT91_SAMA7D65_ADC_TS_CLB_IDX_P4];
> + clb->p6 = buf[AT91_SAMA7D65_ADC_TS_CLB_IDX_P6];
only these indexes and the MAX check above make this different from
the existing function. Maybe we could just store those instead
of a function pointer in the device type specific structure.
> +
> + /*
> + * We prepare here the conversion to milli from micro to avoid
> + * doing it on hotpath.
> + */
> + clb->p1 = clb->p1 / 1000;
> +
> +free_buf:
> + kfree(buf);
> + return ret;
> +}
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