iio: adc: sun4i-gpadc-iio: add support for A33 thermal sensor

This adds support for the Allwinner A33 thermal sensor.

Unlike the A10, A13 and A31, the Allwinner A33 only has one channel
which is dedicated to the thermal sensor. Moreover, its thermal sensor
does not generate interruptions, thus we only need to directly read the
register storing the temperature value.

The MFD used by the A10, A13 and A31, was created to avoid breaking the
DT binding, but since the nodes for the ADC weren't there for the A33,
it is not needed.

Though the A33 does not have an internal ADC, it has a thermal sensor
which shares the same registers with GPADC of the already supported SoCs
and almost the same bits, for the same purpose (thermal sensor).

The thermal sensor behaves exactly the same (except the presence of
interrupts or not) on the different SoCs.

Signed-off-by: Quentin Schulz <quentin.schulz@free-electrons.com>
Acked-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

diff --git a/drivers/iio/adc/Kconfig b/drivers/iio/adc/Kconfig
index 1e25ef0091301c2efbb94b45f9dd9fa6e36c0e2f..f924fa0d4fd692eb53970dded323e9c73d81fd8a 100644 (file)
--- a/drivers/iio/adc/Kconfig
+++ b/drivers/iio/adc/Kconfig
@@ -604,7 +604,7 @@ config STX104
 config SUN4I_GPADC
        tristate "Support for the Allwinner SoCs GPADC"
        depends on IIO
-       depends on MFD_SUN4I_GPADC
+       depends on MFD_SUN4I_GPADC || MACH_SUN8I
        depends on THERMAL || !THERMAL_OF
        help
          Say yes here to build support for Allwinner (A10, A13 and A31) SoCs

diff --git a/drivers/iio/adc/sun4i-gpadc-iio.c b/drivers/iio/adc/sun4i-gpadc-iio.c
index 4c0167562965bb33070d178f7bc745491c195217..b2352730908805f8a29822a6a00413452a3464cb 100644 (file)
--- a/drivers/iio/adc/sun4i-gpadc-iio.c
+++ b/drivers/iio/adc/sun4i-gpadc-iio.c
@@ -85,6 +85,12 @@ static const struct gpadc_data sun6i_gpadc_data = {
        .adc_chan_mask = SUN6I_GPADC_CTRL1_ADC_CHAN_MASK,
 };
 
+static const struct gpadc_data sun8i_a33_gpadc_data = {
+       .temp_offset = -1662,
+       .temp_scale = 162,
+       .tp_mode_en = SUN8I_GPADC_CTRL1_CHOP_TEMP_EN,
+};
+
 struct sun4i_gpadc_iio {
        struct iio_dev                  *indio_dev;
        struct completion               completion;
@@ -96,6 +102,7 @@ struct sun4i_gpadc_iio {
        unsigned int                    temp_data_irq;
        atomic_t                        ignore_temp_data_irq;
        const struct gpadc_data         *data;
+       bool                            no_irq;
        /* prevents concurrent reads of temperature and ADC */
        struct mutex                    mutex;
 };
@@ -138,6 +145,23 @@ static const struct iio_chan_spec sun4i_gpadc_channels_no_temp[] = {
        SUN4I_GPADC_ADC_CHANNEL(3, "adc_chan3"),
 };
 
+static const struct iio_chan_spec sun8i_a33_gpadc_channels[] = {
+       {
+               .type = IIO_TEMP,
+               .info_mask_separate = BIT(IIO_CHAN_INFO_RAW) |
+                                     BIT(IIO_CHAN_INFO_SCALE) |
+                                     BIT(IIO_CHAN_INFO_OFFSET),
+               .datasheet_name = "temp_adc",
+       },
+};
+
+static const struct regmap_config sun4i_gpadc_regmap_config = {
+       .reg_bits = 32,
+       .val_bits = 32,
+       .reg_stride = 4,
+       .fast_io = true,
+};
+
 static int sun4i_prepare_for_irq(struct iio_dev *indio_dev, int channel,
                                 unsigned int irq)
 {
@@ -247,6 +271,17 @@ static int sun4i_gpadc_temp_read(struct iio_dev *indio_dev, int *val)
 {
        struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
 
+       if (info->no_irq) {
+               pm_runtime_get_sync(indio_dev->dev.parent);
+
+               regmap_read(info->regmap, SUN4I_GPADC_TEMP_DATA, val);
+
+               pm_runtime_mark_last_busy(indio_dev->dev.parent);
+               pm_runtime_put_autosuspend(indio_dev->dev.parent);
+
+               return 0;
+       }
+
        return sun4i_gpadc_read(indio_dev, 0, val, info->temp_data_irq);
 }
 
@@ -454,6 +489,58 @@ static int sun4i_irq_init(struct platform_device *pdev, const char *name,
        return 0;
 }
 
+static const struct of_device_id sun4i_gpadc_of_id[] = {
+       {
+               .compatible = "allwinner,sun8i-a33-ths",
+               .data = &sun8i_a33_gpadc_data,
+       },
+       { /* sentinel */ }
+};
+
+static int sun4i_gpadc_probe_dt(struct platform_device *pdev,
+                               struct iio_dev *indio_dev)
+{
+       struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
+       const struct of_device_id *of_dev;
+       struct thermal_zone_device *tzd;
+       struct resource *mem;
+       void __iomem *base;
+       int ret;
+
+       of_dev = of_match_device(sun4i_gpadc_of_id, &pdev->dev);
+       if (!of_dev)
+               return -ENODEV;
+
+       info->no_irq = true;
+       info->data = (struct gpadc_data *)of_dev->data;
+       indio_dev->num_channels = ARRAY_SIZE(sun8i_a33_gpadc_channels);
+       indio_dev->channels = sun8i_a33_gpadc_channels;
+
+       mem = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+       base = devm_ioremap_resource(&pdev->dev, mem);
+       if (IS_ERR(base))
+               return PTR_ERR(base);
+
+       info->regmap = devm_regmap_init_mmio(&pdev->dev, base,
+                                            &sun4i_gpadc_regmap_config);
+       if (IS_ERR(info->regmap)) {
+               ret = PTR_ERR(info->regmap);
+               dev_err(&pdev->dev, "failed to init regmap: %d\n", ret);
+               return ret;
+       }
+
+       if (!IS_ENABLED(CONFIG_THERMAL_OF))
+               return 0;
+
+       tzd = devm_thermal_zone_of_sensor_register(&pdev->dev, 0, info,
+                                                  &sun4i_ts_tz_ops);
+       if (IS_ERR(tzd))
+               dev_err(&pdev->dev, "could not register thermal sensor: %ld\n",
+                       PTR_ERR(tzd));
+
+       return PTR_ERR_OR_ZERO(tzd);
+}
+
 static int sun4i_gpadc_probe_mfd(struct platform_device *pdev,
                                 struct iio_dev *indio_dev)
 {
@@ -462,6 +549,7 @@ static int sun4i_gpadc_probe_mfd(struct platform_device *pdev,
                dev_get_drvdata(pdev->dev.parent);
        int ret;
 
+       info->no_irq = false;
        info->regmap = sun4i_gpadc_dev->regmap;
 
        indio_dev->num_channels = ARRAY_SIZE(sun4i_gpadc_channels);
@@ -561,7 +649,11 @@ static int sun4i_gpadc_probe(struct platform_device *pdev)
        indio_dev->info = &sun4i_gpadc_iio_info;
        indio_dev->modes = INDIO_DIRECT_MODE;
 
-       ret = sun4i_gpadc_probe_mfd(pdev, indio_dev);
+       if (pdev->dev.of_node)
+               ret = sun4i_gpadc_probe_dt(pdev, indio_dev);
+       else
+               ret = sun4i_gpadc_probe_mfd(pdev, indio_dev);
+
        if (ret)
                return ret;
 
@@ -580,7 +672,7 @@ static int sun4i_gpadc_probe(struct platform_device *pdev)
        return 0;
 
 err_map:
-       if (IS_ENABLED(CONFIG_THERMAL_OF))
+       if (!info->no_irq && IS_ENABLED(CONFIG_THERMAL_OF))
                iio_map_array_unregister(indio_dev);
 
        pm_runtime_put(&pdev->dev);
@@ -592,10 +684,11 @@ err_map:
 static int sun4i_gpadc_remove(struct platform_device *pdev)
 {
        struct iio_dev *indio_dev = platform_get_drvdata(pdev);
+       struct sun4i_gpadc_iio *info = iio_priv(indio_dev);
 
        pm_runtime_put(&pdev->dev);
        pm_runtime_disable(&pdev->dev);
-       if (IS_ENABLED(CONFIG_THERMAL_OF))
+       if (!info->no_irq && IS_ENABLED(CONFIG_THERMAL_OF))
                iio_map_array_unregister(indio_dev);
 
        return 0;
@@ -611,6 +704,7 @@ static const struct platform_device_id sun4i_gpadc_id[] = {
 static struct platform_driver sun4i_gpadc_driver = {
        .driver = {
                .name = "sun4i-gpadc-iio",
+               .of_match_table = sun4i_gpadc_of_id,
                .pm = &sun4i_gpadc_pm_ops,
        },
        .id_table = sun4i_gpadc_id,

diff --git a/include/linux/mfd/sun4i-gpadc.h b/include/linux/mfd/sun4i-gpadc.h
index 509e736d27fba8cf66e389e7f280133a73b2a02d..139872c2e0fe0ffe9517d8f13db65efcd5bc42ff 100644 (file)
--- a/include/linux/mfd/sun4i-gpadc.h
+++ b/include/linux/mfd/sun4i-gpadc.h
@@ -38,6 +38,10 @@
 #define SUN6I_GPADC_CTRL1_ADC_CHAN_SELECT(x)           (GENMASK(3, 0) & BIT(x))
 #define SUN6I_GPADC_CTRL1_ADC_CHAN_MASK                        GENMASK(3, 0)
 
+/* TP_CTRL1 bits for sun8i SoCs */
+#define SUN8I_GPADC_CTRL1_CHOP_TEMP_EN                 BIT(8)
+#define SUN8I_GPADC_CTRL1_GPADC_CALI_EN                        BIT(7)
+
 #define SUN4I_GPADC_CTRL2                              0x08
 
 #define SUN4I_GPADC_CTRL2_TP_SENSITIVE_ADJUST(x)       ((GENMASK(3, 0) & (x)) << 28)