[PATCH 6/7] iio: adc: sun4i-gpadc-iio: add support for H6 thermal sensor

Yangtao Li
2019-05-03T07:28:43Z

This patch adds support for the H6 ths sensor.

TODO: calibrate thermal sensor by using information from sid.

Signed-off-by: Yangtao Li <tiny.windzz@gmail.com>
---
drivers/iio/adc/sun4i-gpadc-iio.c | 65 +++++++++++++++++++++++++++++++
include/linux/mfd/sun4i-gpadc.h | 9 +++++
2 files changed, 74 insertions(+)

diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c
index f24eb76d65c0..9b6fc592f54c 100644
--- a/drivers/iio/adc/sun4i-gpadc-iio.c
+++ b/drivers/iio/adc/sun4i-gpadc-iio.c
@@ -120,6 +120,20 @@ static const struct gpadc_data sun8i_a33_gpadc_data = {
.temp_data_base = SUN4I_GPADC_TEMP_DATA,
};

+static int sun50i_gpadc_disable(struct sun4i_gpadc_iio *info);
+static int sun50i_gpadc_enable(struct sun4i_gpadc_iio *info);
+
+static const struct gpadc_data sun50i_h6_gpadc_data = {
+ .temp_offset = -2809,
+ .temp_scale = -67,
+ .has_bus_clk = true,
+ .has_bus_rst = true,
+ .gpadc_enable = sun50i_gpadc_enable,
+ .gpadc_disable = sun50i_gpadc_disable,
+ .sensor_count = 2,
+ .temp_data_base = SUN50I_H6_GPADC_TEMP_DATA,
+};
+
struct sun4i_sensor_tzd {
struct sun4i_gpadc_iio *info;
struct thermal_zone_device *tzd;
@@ -452,6 +466,53 @@ static int sun4i_gpadc_enable(struct sun4i_gpadc_iio *info)
return 0;
}

+static int sun50i_gpadc_enable(struct sun4i_gpadc_iio *info)
+{
+ int ret, val;
+
+ ret = reset_control_deassert(info->reset);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(info->bus_clk);
+ if (ret)
+ goto assert_reset;
+
+ /*
+ * clkin = 24MHz
+ * T acquire = clkin / (SUN50I_GPADC_CTRL0_T_ACQ + 1)
+ * = 20us
+ */
+ regmap_write(info->regmap, SUN4I_GPADC_CTRL0,
+ SUN50I_GPADC_CTRL0_T_ACQ(479));
+ /* average over 4 samples */
+ regmap_write(info->regmap, SUN50I_H6_GPADC_CTRL3,
+ SUN4I_GPADC_CTRL3_FILTER_EN |
+ SUN4I_GPADC_CTRL3_FILTER_TYPE(1));
+ /* period = (SUN50I_GPADC_TPR_TEMP_PERIOD + 1) * 4096 / clkin; ~10ms */
+ regmap_write(info->regmap, SUN50I_GPADC_TPR,
+ SUN50I_GPADC_TPR_TEMP_PERIOD(58));
+ /* TODO: calibrate ths */
+ /* enable sensor */
+ val = GENMASK(info->data->sensor_count - 1, 0);
+ regmap_write(info->regmap, SUN4I_GPADC_CTRL1, val);
+
+ return 0;
+
+assert_reset:
+ reset_control_assert(info->reset);
+
+ return ret;
+}
+
+static int sun50i_gpadc_disable(struct sun4i_gpadc_iio *info)
+{
+ clk_disable_unprepare(info->bus_clk);
+ reset_control_assert(info->reset);
+
+ return 0;
+}
+
static int sun4i_gpadc_runtime_suspend(struct device *dev)
{
struct sun4i_gpadc_iio *info = iio_priv(dev_get_drvdata(dev));
@@ -546,6 +607,10 @@ static const struct of_device_id sun4i_gpadc_of_id[] = {
.compatible = "allwinner,sun8i-a33-ths",
.data = &sun8i_a33_gpadc_data,
},
+ {
+ .compatible = "allwinner,sun50i-h6-ths",
+ .data = &sun50i_h6_gpadc_data,
+ },
{ /* sentinel */ }
};

diff --git a/include/linux/mfd/sun4i-gpadc.h b/include/linux/mfd/sun4i-gpadc.h
index 139872c2e0fe..f505013e9c0d 100644
--- a/include/linux/mfd/sun4i-gpadc.h
+++ b/include/linux/mfd/sun4i-gpadc.h
@@ -19,6 +19,9 @@
#define SUN4I_GPADC_CTRL0_FS_DIV(x) ((GENMASK(3, 0) & (x)) << 16)
#define SUN4I_GPADC_CTRL0_T_ACQ(x) (GENMASK(15, 0) & (x))

+/* TP_CTRL0 bits for sun50i SOCs */
+#define SUN50I_GPADC_CTRL0_T_ACQ(x) ((GENMASK(15, 0) & (x)) << 16)
+
#define SUN4I_GPADC_CTRL1 0x04

#define SUN4I_GPADC_CTRL1_STYLUS_UP_DEBOUNCE(x) ((GENMASK(7, 0) & (x)) << 12)
@@ -49,6 +52,9 @@
#define SUN4I_GPADC_CTRL2_PRE_MEA_EN BIT(24)
#define SUN4I_GPADC_CTRL2_PRE_MEA_THRE_CNT(x) (GENMASK(23, 0) & (x))

+#define SUN50I_GPADC_TPR 0x08
+#define SUN50I_GPADC_TPR_TEMP_PERIOD(x) ((GENMASK(19, 0) & (x)) << 12)
+
#define SUN4I_GPADC_CTRL3 0x0c

#define SUN4I_GPADC_CTRL3_FILTER_EN BIT(2)
@@ -84,6 +90,9 @@
#define SUN4I_GPADC_TEMP_DATA 0x20
#define SUN4I_GPADC_DATA 0x24

+#define SUN50I_H6_GPADC_CTRL3 0x30
+#define SUN50I_H6_GPADC_TEMP_DATA 0xc0
+
#define SUN4I_GPADC_IRQ_FIFO_DATA 0
#define SUN4I_GPADC_IRQ_TEMP_DATA 1

--
2.17.1