[PATCH V3 5/7] iio: adc: sc27xx: add support for PMIC sc2720 and sc2721

From: Cixi Geng
Date: Thu Apr 07 2022 - 04:22:43 EST

From: Cixi Geng <cixi.geng1@xxxxxxxxxx>

sc2720 and sc2721 is the product of sc27xx series.

Co-developed-by: Yuming Zhu <yuming.zhu1@xxxxxxxxxx>
Signed-off-by: Yuming Zhu <yuming.zhu1@xxxxxxxxxx>
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
Signed-off-by: Cixi Geng <cixi.geng1@xxxxxxxxxx>
---
drivers/iio/adc/sc27xx_adc.c | 211 ++++++++++++++++++++++++++++++++++-
1 file changed, 209 insertions(+), 2 deletions(-)

diff --git a/drivers/iio/adc/sc27xx_adc.c b/drivers/iio/adc/sc27xx_adc.c
index 60c0a6aa3f45..eb9e789dd8ee 100644
--- 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 +71,20 @@
#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
+
+enum sc27xx_pmic_type {
+ SC27XX_ADC,
+ SC2721_ADC,
+};
+
struct sc27xx_adc_data {
struct device *dev;
+ struct regulator *volref;
struct regmap *regmap;
/*
* One hardware spinlock to synchronize between the multiple
@@ -87,6 +103,7 @@ struct sc27xx_adc_data {
* in the device data structure.
*/
struct sc27xx_adc_variant_data {
+ enum sc27xx_pmic_type pmic_type;
u32 module_en;
u32 clk_en;
u32 scale_shift;
@@ -131,6 +148,16 @@ 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;
@@ -192,6 +219,94 @@ 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) {
@@ -220,6 +335,34 @@ 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;
@@ -237,7 +380,7 @@ 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);
@@ -246,10 +389,25 @@ 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->pmic_type == SC2721_ADC) && (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);
@@ -300,6 +458,17 @@ static int sc27xx_adc_read(struct sc27xx_adc_data *data, int channel,
regmap_update_bits(data->regmap, data->base + SC27XX_ADC_CTL,
SC27XX_ADC_EN, 0);

+regulator_restore:
+ if ((data->var_data->pmic_type == SC2721_ADC) && (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);

@@ -540,6 +709,7 @@ static void sc27xx_adc_disable(void *_data)
}

static const struct sc27xx_adc_variant_data sc2731_data = {
+ .pmic_type = SC27XX_ADC,
.module_en = SC2731_MODULE_EN,
.clk_en = SC2731_ARM_CLK_EN,
.scale_shift = SC27XX_ADC_SCALE_SHIFT,
@@ -550,6 +720,30 @@ static const struct sc27xx_adc_variant_data sc2731_data = {
.get_ratio = sc2731_adc_get_ratio,
};

+static const struct sc27xx_adc_variant_data sc2721_data = {
+ .pmic_type = SC2721_ADC,
+ .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,
+};
+
+static const struct sc27xx_adc_variant_data sc2720_data = {
+ .pmic_type = SC27XX_ADC,
+ .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,
+};
+
static int sc27xx_adc_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
@@ -600,6 +794,17 @@ static int sc27xx_adc_probe(struct platform_device *pdev)
}

sc27xx_data->dev = dev;
+ if (pdata->pmic_type == SC2721_ADC) {
+ sc27xx_data->volref = devm_regulator_get(dev, "vref");
+ if (IS_ERR(sc27xx_data->volref)) {
+ ret = PTR_ERR(sc27xx_data->volref);
+ if (ret == -ENODEV)
+ dev_err(dev, "failed to supply the regulator\n");
+ dev_err(dev, "failed to get ADC volref, the err volref: %d\n", ret);
+ return ret;
+ }
+ }
+
sc27xx_data->var_data = pdata;
sc27xx_data->var_data->init_scale(sc27xx_data);

@@ -629,6 +834,8 @@ 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);
--
2.25.1