[PATCH v4 6/8] iio: sx9324: Add Setting for internal compensation resistor

[Gwendal Grignou <gwendal@chromium.org>]

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

Signed-off-by: Gwendal Grignou <gwendal@chromium.org>
---
Changes since v3:
- Use match_string() to prevent incorrect matching.

Changes since v2:
- No changes.

Changes since v1:
- No changes.

 drivers/iio/proximity/sx9324.c | 21 ++++++++++++++++++++-
 1 file changed, 20 insertions(+), 1 deletion(-)

diff --git a/drivers/iio/proximity/sx9324.c b/drivers/iio/proximity/sx9324.c
index 691700de0b9d4..2dcfac09644bd 100644
--- 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
@@ -769,7 +774,7 @@ 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 },
@@ -848,6 +853,8 @@ 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"
@@ -855,6 +862,7 @@ 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) {
@@ -875,6 +883,17 @@ 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)
-- 
2.35.1.1094.g7c7d902a7c-goog