iio: adc: sc27xx: add support for PMIC sc2720 and sc2721

sc2720 and sc2721 is the product of sc27xx series.

Co-developed-by: Yuming Zhu <yuming.zhu1@unisoc.com>
Signed-off-by: Yuming Zhu <yuming.zhu1@unisoc.com>
Signed-off-by: Cixi Geng <cixi.geng1@unisoc.com>
Link: https://lore.kernel.org/r/20220419142458.884933-7-gengcixi@gmail.com
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/adc/sc27xx_adc.c b/drivers/iio/adc/sc27xx_adc.c
index 1d02390..02d6e81 100644 (file)
--- a/drivers/iio/adc/sc27xx_adc.c
+++ b/drivers/iio/adc/sc27xx_adc.c
@@ -9,11 +9,13 @@
 #include <linux/of_device.h>
 #include <linux/platform_device.h>
 #include <linux/regmap.h>
+#include <linux/regulator/consumer.h>
 #include <linux/slab.h>
 
 /* PMIC global registers definition */
 #define SC2731_MODULE_EN               0xc08
 #define SC27XX_MODULE_ADC_EN           BIT(5)
+#define SC2721_ARM_CLK_EN              0xc0c
 #define SC2731_ARM_CLK_EN              0xc10
 #define SC27XX_CLK_ADC_EN              BIT(5)
 #define SC27XX_CLK_ADC_CLK_EN          BIT(6)
@@ -37,7 +39,9 @@
 /* Bits and mask definition for SC27XX_ADC_CH_CFG register */
 #define SC27XX_ADC_CHN_ID_MASK         GENMASK(4, 0)
 #define SC27XX_ADC_SCALE_MASK          GENMASK(10, 9)
+#define SC2721_ADC_SCALE_MASK          BIT(5)
 #define SC27XX_ADC_SCALE_SHIFT         9
+#define SC2721_ADC_SCALE_SHIFT         5
 
 /* Bits definitions for SC27XX_ADC_INT_EN registers */
 #define SC27XX_ADC_IRQ_EN              BIT(0)
@@ -67,8 +71,15 @@
 #define SC27XX_RATIO_NUMERATOR_OFFSET  16
 #define SC27XX_RATIO_DENOMINATOR_MASK  GENMASK(15, 0)
 
+/* ADC specific channel reference voltage 3.5V */
+#define SC27XX_ADC_REFVOL_VDD35                3500000
+
+/* ADC default channel reference voltage is 2.8V */
+#define SC27XX_ADC_REFVOL_VDD28                2800000
+
 struct sc27xx_adc_data {
        struct device *dev;
+       struct regulator *volref;
        struct regmap *regmap;
        /*
         * One hardware spinlock to synchronize between the multiple
@@ -95,6 +106,7 @@ struct sc27xx_adc_variant_data {
        const struct sc27xx_adc_linear_graph *sscale_cal;
        void (*init_scale)(struct sc27xx_adc_data *data);
        int (*get_ratio)(int channel, int scale);
+       bool set_volref;
 };
 
 struct sc27xx_adc_linear_graph {
@@ -130,6 +142,16 @@ static const struct sc27xx_adc_linear_graph sc2731_small_scale_graph_calib = {
        100, 84,
 };
 
+static const struct sc27xx_adc_linear_graph big_scale_graph_calib = {
+       4200, 856,
+       3600, 733,
+};
+
+static const struct sc27xx_adc_linear_graph small_scale_graph_calib = {
+       1000, 833,
+       100, 80,
+};
+
 static int sc27xx_adc_get_calib_data(u32 calib_data, int calib_adc)
 {
        return ((calib_data & 0xff) + calib_adc - 128) * 4;
@@ -191,6 +213,94 @@ static int sc27xx_adc_scale_calibration(struct sc27xx_adc_data *data,
        return 0;
 }
 
+static int sc2720_adc_get_ratio(int channel, int scale)
+{
+       switch (channel) {
+       case 14:
+               switch (scale) {
+               case 0:
+                       return SC27XX_VOLT_RATIO(68, 900);
+               case 1:
+                       return SC27XX_VOLT_RATIO(68, 1760);
+               case 2:
+                       return SC27XX_VOLT_RATIO(68, 2327);
+               case 3:
+                       return SC27XX_VOLT_RATIO(68, 3654);
+               default:
+                       return SC27XX_VOLT_RATIO(1, 1);
+               }
+       case 16:
+               switch (scale) {
+               case 0:
+                       return SC27XX_VOLT_RATIO(48, 100);
+               case 1:
+                       return SC27XX_VOLT_RATIO(480, 1955);
+               case 2:
+                       return SC27XX_VOLT_RATIO(480, 2586);
+               case 3:
+                       return SC27XX_VOLT_RATIO(48, 406);
+               default:
+                       return SC27XX_VOLT_RATIO(1, 1);
+               }
+       case 21:
+       case 22:
+       case 23:
+               switch (scale) {
+               case 0:
+                       return SC27XX_VOLT_RATIO(3, 8);
+               case 1:
+                       return SC27XX_VOLT_RATIO(375, 1955);
+               case 2:
+                       return SC27XX_VOLT_RATIO(375, 2586);
+               case 3:
+                       return SC27XX_VOLT_RATIO(300, 3248);
+               default:
+                       return SC27XX_VOLT_RATIO(1, 1);
+               }
+       default:
+               switch (scale) {
+               case 0:
+                       return SC27XX_VOLT_RATIO(1, 1);
+               case 1:
+                       return SC27XX_VOLT_RATIO(1000, 1955);
+               case 2:
+                       return SC27XX_VOLT_RATIO(1000, 2586);
+               case 3:
+                       return SC27XX_VOLT_RATIO(100, 406);
+               default:
+                       return SC27XX_VOLT_RATIO(1, 1);
+               }
+       }
+       return SC27XX_VOLT_RATIO(1, 1);
+}
+
+static int sc2721_adc_get_ratio(int channel, int scale)
+{
+       switch (channel) {
+       case 1:
+       case 2:
+       case 3:
+       case 4:
+               return scale ? SC27XX_VOLT_RATIO(400, 1025) :
+                       SC27XX_VOLT_RATIO(1, 1);
+       case 5:
+               return SC27XX_VOLT_RATIO(7, 29);
+       case 7:
+       case 9:
+               return scale ? SC27XX_VOLT_RATIO(100, 125) :
+                       SC27XX_VOLT_RATIO(1, 1);
+       case 14:
+               return SC27XX_VOLT_RATIO(68, 900);
+       case 16:
+               return SC27XX_VOLT_RATIO(48, 100);
+       case 19:
+               return SC27XX_VOLT_RATIO(1, 3);
+       default:
+               return SC27XX_VOLT_RATIO(1, 1);
+       }
+       return SC27XX_VOLT_RATIO(1, 1);
+}
+
 static int sc2731_adc_get_ratio(int channel, int scale)
 {
        switch (channel) {
@@ -219,6 +329,34 @@ static int sc2731_adc_get_ratio(int channel, int scale)
 /*
  * According to the datasheet set specific value on some channel.
  */
+static void sc2720_adc_scale_init(struct sc27xx_adc_data *data)
+{
+       int i;
+
+       for (i = 0; i < SC27XX_ADC_CHANNEL_MAX; i++) {
+               switch (i) {
+               case 5:
+                       data->channel_scale[i] = 3;
+                       break;
+               case 7:
+               case 9:
+                       data->channel_scale[i] = 2;
+                       break;
+               case 13:
+                       data->channel_scale[i] = 1;
+                       break;
+               case 19:
+               case 30:
+               case 31:
+                       data->channel_scale[i] = 3;
+                       break;
+               default:
+                       data->channel_scale[i] = 0;
+                       break;
+               }
+       }
+}
+
 static void sc2731_adc_scale_init(struct sc27xx_adc_data *data)
 {
        int i;
@@ -241,7 +379,7 @@ static void sc2731_adc_scale_init(struct sc27xx_adc_data *data)
 static int sc27xx_adc_read(struct sc27xx_adc_data *data, int channel,
                           int scale, int *val)
 {
-       int ret;
+       int ret, ret_volref;
        u32 tmp, value, status;
 
        ret = hwspin_lock_timeout_raw(data->hwlock, SC27XX_ADC_HWLOCK_TIMEOUT);
@@ -250,10 +388,25 @@ static int sc27xx_adc_read(struct sc27xx_adc_data *data, int channel,
                return ret;
        }
 
+       /*
+        * According to the sc2721 chip data sheet, the reference voltage of
+        * specific channel 30 and channel 31 in ADC module needs to be set from
+        * the default 2.8v to 3.5v.
+        */
+       if ((data->var_data->set_volref) && (channel == 30 || channel == 31)) {
+               ret = regulator_set_voltage(data->volref,
+                                       SC27XX_ADC_REFVOL_VDD35,
+                                       SC27XX_ADC_REFVOL_VDD35);
+               if (ret) {
+                       dev_err(data->dev, "failed to set the volref 3.5v\n");
+                       goto unlock_adc;
+               }
+       }
+
        ret = regmap_update_bits(data->regmap, data->base + SC27XX_ADC_CTL,
                                 SC27XX_ADC_EN, SC27XX_ADC_EN);
        if (ret)
-               goto unlock_adc;
+               goto regulator_restore;
 
        ret = regmap_update_bits(data->regmap, data->base + SC27XX_ADC_INT_CLR,
                                 SC27XX_ADC_IRQ_CLR, SC27XX_ADC_IRQ_CLR);
@@ -303,6 +456,17 @@ static int sc27xx_adc_read(struct sc27xx_adc_data *data, int channel,
 disable_adc:
        regmap_update_bits(data->regmap, data->base + SC27XX_ADC_CTL,
                           SC27XX_ADC_EN, 0);
+regulator_restore:
+       if ((data->var_data->set_volref) && (channel == 30 || channel == 31)) {
+               ret_volref = regulator_set_voltage(data->volref,
+                                           SC27XX_ADC_REFVOL_VDD28,
+                                           SC27XX_ADC_REFVOL_VDD28);
+               if (ret_volref) {
+                       dev_err(data->dev, "failed to set the volref 2.8v,ret_volref = 0x%x\n",
+                                        ret_volref);
+                       ret = ret || ret_volref;
+               }
+       }
 unlock_adc:
        hwspin_unlock_raw(data->hwlock);
 
@@ -551,6 +715,31 @@ static const struct sc27xx_adc_variant_data sc2731_data = {
        .sscale_cal = &sc2731_small_scale_graph_calib,
        .init_scale = sc2731_adc_scale_init,
        .get_ratio = sc2731_adc_get_ratio,
+       .set_volref = false,
+};
+
+static const struct sc27xx_adc_variant_data sc2721_data = {
+       .module_en = SC2731_MODULE_EN,
+       .clk_en = SC2721_ARM_CLK_EN,
+       .scale_shift = SC2721_ADC_SCALE_SHIFT,
+       .scale_mask = SC2721_ADC_SCALE_MASK,
+       .bscale_cal = &sc2731_big_scale_graph_calib,
+       .sscale_cal = &sc2731_small_scale_graph_calib,
+       .init_scale = sc2731_adc_scale_init,
+       .get_ratio = sc2721_adc_get_ratio,
+       .set_volref = true,
+};
+
+static const struct sc27xx_adc_variant_data sc2720_data = {
+       .module_en = SC2731_MODULE_EN,
+       .clk_en = SC2721_ARM_CLK_EN,
+       .scale_shift = SC27XX_ADC_SCALE_SHIFT,
+       .scale_mask = SC27XX_ADC_SCALE_MASK,
+       .bscale_cal = &big_scale_graph_calib,
+       .sscale_cal = &small_scale_graph_calib,
+       .init_scale = sc2720_adc_scale_init,
+       .get_ratio = sc2720_adc_get_ratio,
+       .set_volref = false,
 };
 
 static int sc27xx_adc_probe(struct platform_device *pdev)
@@ -603,6 +792,14 @@ static int sc27xx_adc_probe(struct platform_device *pdev)
        }
 
        sc27xx_data->dev = dev;
+       if (pdata->set_volref) {
+               sc27xx_data->volref = devm_regulator_get(dev, "vref");
+               if (IS_ERR(sc27xx_data->volref)) {
+                       ret = PTR_ERR(sc27xx_data->volref);
+                       return dev_err_probe(dev, ret, "failed to get ADC volref\n");
+               }
+       }
+
        sc27xx_data->var_data = pdata;
        sc27xx_data->var_data->init_scale(sc27xx_data);
 
@@ -632,6 +829,8 @@ static int sc27xx_adc_probe(struct platform_device *pdev)
 
 static const struct of_device_id sc27xx_adc_of_match[] = {
        { .compatible = "sprd,sc2731-adc", .data = &sc2731_data},
+       { .compatible = "sprd,sc2721-adc", .data = &sc2721_data},
+       { .compatible = "sprd,sc2720-adc", .data = &sc2720_data},
        { }
 };
 MODULE_DEVICE_TABLE(of, sc27xx_adc_of_match);