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path: root/drivers/iio/health/max30100.c
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Diffstat (limited to 'drivers/iio/health/max30100.c')
-rw-r--r--drivers/iio/health/max30100.c43
1 files changed, 37 insertions, 6 deletions
diff --git a/drivers/iio/health/max30100.c b/drivers/iio/health/max30100.c
index e08d143a707c..3d441013893c 100644
--- a/drivers/iio/health/max30100.c
+++ b/drivers/iio/health/max30100.c
@@ -5,7 +5,6 @@
* Copyright (C) 2015, 2018
* Author: Matt Ranostay <matt.ranostay@konsulko.com>
*
- * TODO: enable pulse length controls via device tree properties
*/
#include <linux/module.h>
@@ -18,11 +17,11 @@
#include <linux/mutex.h>
#include <linux/property.h>
#include <linux/regmap.h>
+#include <linux/bitfield.h>
#include <linux/iio/iio.h>
#include <linux/iio/buffer.h>
#include <linux/iio/kfifo_buf.h>
-#define MAX30100_REGMAP_NAME "max30100_regmap"
#define MAX30100_DRV_NAME "max30100"
#define MAX30100_REG_INT_STATUS 0x00
@@ -53,9 +52,13 @@
#define MAX30100_REG_MODE_CONFIG_PWR BIT(7)
#define MAX30100_REG_SPO2_CONFIG 0x07
+#define MAX30100_REG_SPO2_CONFIG_PW_MASK GENMASK(1, 0)
+#define MAX30100_REG_SPO2_CONFIG_200US 0x0
+#define MAX30100_REG_SPO2_CONFIG_400US 0x1
+#define MAX30100_REG_SPO2_CONFIG_800US 0x2
+#define MAX30100_REG_SPO2_CONFIG_1600US 0x3
#define MAX30100_REG_SPO2_CONFIG_100HZ BIT(2)
#define MAX30100_REG_SPO2_CONFIG_HI_RES_EN BIT(6)
-#define MAX30100_REG_SPO2_CONFIG_1600US 0x3
#define MAX30100_REG_LED_CONFIG 0x09
#define MAX30100_REG_LED_CONFIG_LED_MASK 0x0f
@@ -94,7 +97,7 @@ static bool max30100_is_volatile_reg(struct device *dev, unsigned int reg)
}
static const struct regmap_config max30100_regmap_config = {
- .name = MAX30100_REGMAP_NAME,
+ .name = "max30100_regmap",
.reg_bits = 8,
.val_bits = 8,
@@ -307,19 +310,47 @@ static int max30100_led_init(struct max30100_data *data)
MAX30100_REG_LED_CONFIG_LED_MASK, reg);
}
+static int max30100_get_pulse_width(unsigned int pwidth_us)
+{
+ switch (pwidth_us) {
+ case 200:
+ return MAX30100_REG_SPO2_CONFIG_200US;
+ case 400:
+ return MAX30100_REG_SPO2_CONFIG_400US;
+ case 800:
+ return MAX30100_REG_SPO2_CONFIG_800US;
+ case 1600:
+ return MAX30100_REG_SPO2_CONFIG_1600US;
+ default:
+ return -EINVAL;
+ }
+}
+
static int max30100_chip_init(struct max30100_data *data)
{
int ret;
+ int pulse_width;
+ /* set default LED pulse-width to 1600 us */
+ unsigned int pulse_us = 1600;
+ struct device *dev = &data->client->dev;
/* setup LED current settings */
ret = max30100_led_init(data);
if (ret)
return ret;
+ /* Read LED pulse-width-us from DT */
+ device_property_read_u32(dev, "maxim,pulse-width-us", &pulse_us);
+
+ pulse_width = max30100_get_pulse_width(pulse_us);
+ if (pulse_width < 0)
+ return dev_err_probe(dev, pulse_width, "invalid LED pulse-width %uus\n", pulse_us);
+
/* enable hi-res SPO2 readings at 100Hz */
ret = regmap_write(data->regmap, MAX30100_REG_SPO2_CONFIG,
MAX30100_REG_SPO2_CONFIG_HI_RES_EN |
- MAX30100_REG_SPO2_CONFIG_100HZ);
+ MAX30100_REG_SPO2_CONFIG_100HZ |
+ FIELD_PREP(MAX30100_REG_SPO2_CONFIG_PW_MASK, pulse_width));
if (ret)
return ret;
@@ -483,7 +514,7 @@ static void max30100_remove(struct i2c_client *client)
static const struct i2c_device_id max30100_id[] = {
{ "max30100" },
- {}
+ { }
};
MODULE_DEVICE_TABLE(i2c, max30100_id);