iio: sx9324: Add Setting for internal compensation resistor

Based on device tree setting, set the internal compensation resistor.

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Stephen Boyd <swboyd@chromium.org>
Link: https://lore.kernel.org/r/20220429220144.1476049-7-gwendal@chromium.org
Signed-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

diff --git a/drivers/iio/proximity/sx9324.c b/drivers/iio/proximity/sx9324.c
index 28e2672..926a0da 100644 (file)
--- a/drivers/iio/proximity/sx9324.c
+++ b/drivers/iio/proximity/sx9324.c
@@ -52,6 +52,11 @@
 #define SX9324_REG_CLK_SPRD            0x15
 
 #define SX9324_REG_AFE_CTRL0           0x20
+#define SX9324_REG_AFE_CTRL0_RINT_SHIFT                6
+#define SX9324_REG_AFE_CTRL0_RINT_MASK \
+       GENMASK(SX9324_REG_AFE_CTRL0_RINT_SHIFT + 1, \
+               SX9324_REG_AFE_CTRL0_RINT_SHIFT)
+#define SX9324_REG_AFE_CTRL0_RINT_LOWEST       0x00
 #define SX9324_REG_AFE_CTRL1           0x21
 #define SX9324_REG_AFE_CTRL2           0x22
 #define SX9324_REG_AFE_CTRL3           0x23
@@ -783,7 +788,7 @@ static const struct sx_common_reg_default sx9324_default_regs[] = {
         */
        { SX9324_REG_GNRL_CTRL1, SX9324_REG_GNRL_CTRL1_PAUSECTRL },
 
-       { SX9324_REG_AFE_CTRL0, 0x00 },
+       { SX9324_REG_AFE_CTRL0, SX9324_REG_AFE_CTRL0_RINT_LOWEST },
        { SX9324_REG_AFE_CTRL3, 0x00 },
        { SX9324_REG_AFE_CTRL4, SX9324_REG_AFE_CTRL4_FREQ_83_33HZ |
                SX9324_REG_AFE_CTRL4_RES_100 },
@@ -864,6 +869,8 @@ static const struct sx_common_reg_default *
 sx9324_get_default_reg(struct device *dev, int idx,
                       struct sx_common_reg_default *reg_def)
 {
+       static const char * const sx9324_rints[] = { "lowest", "low", "high",
+               "highest" };
 #define SX9324_PIN_DEF "semtech,ph0-pin"
 #define SX9324_RESOLUTION_DEF "semtech,ph01-resolution"
 #define SX9324_PROXRAW_DEF "semtech,ph01-proxraw-strength"
@@ -871,6 +878,7 @@ sx9324_get_default_reg(struct device *dev, int idx,
        char prop[] = SX9324_PROXRAW_DEF;
        u32 start = 0, raw = 0, pos = 0;
        int ret, count, ph, pin;
+       const char *res;
 
        memcpy(reg_def, &sx9324_default_regs[idx], sizeof(*reg_def));
        switch (reg_def->reg) {
@@ -891,6 +899,17 @@ sx9324_get_default_reg(struct device *dev, int idx,
                               SX9324_REG_AFE_PH0_PIN_MASK(pin);
                reg_def->def = raw;
                break;
+       case SX9324_REG_AFE_CTRL0:
+               ret = device_property_read_string(dev,
+                               "semtech,int-comp-resistor", &res);
+               if (ret)
+                       break;
+               ret = match_string(sx9324_rints, ARRAY_SIZE(sx9324_rints), res);
+               if (ret < 0)
+                       break;
+               reg_def->def &= ~SX9324_REG_AFE_CTRL0_RINT_MASK;
+               reg_def->def |= ret << SX9324_REG_AFE_CTRL0_RINT_SHIFT;
+               break;
        case SX9324_REG_AFE_CTRL4:
        case SX9324_REG_AFE_CTRL7:
                if (reg_def->reg == SX9324_REG_AFE_CTRL4)