iio: health: max30100: correct FIFO check condition

[deliverable/linux.git] / drivers / iio / health / max30100.c

diff --git a/drivers/iio/health/max30100.c b/drivers/iio/health/max30100.c
index 9d1c81f91dd771826638aaa8eb78824daf7a4aa3..90ab8a2d2846f8a8591ee6b1615dce2c984020ef 100644 (file)
--- a/drivers/iio/health/max30100.c
+++ b/drivers/iio/health/max30100.c
@@ -13,7 +13,7 @@
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  * GNU General Public License for more details.
  *
- * TODO: allow LED current and pulse length controls via device tree properties
+ * TODO: enable pulse length controls via device tree properties
  */
 
 #include <linux/module.h>
@@ -24,6 +24,7 @@
 #include <linux/irq.h>
 #include <linux/i2c.h>
 #include <linux/mutex.h>
+#include <linux/of.h>
 #include <linux/regmap.h>
 #include <linux/iio/iio.h>
 #include <linux/iio/buffer.h>
@@ -65,6 +66,7 @@
 #define MAX30100_REG_SPO2_CONFIG_1600US                0x3
 
 #define MAX30100_REG_LED_CONFIG                        0x09
+#define MAX30100_REG_LED_CONFIG_LED_MASK       0x0f
 #define MAX30100_REG_LED_CONFIG_RED_LED_SHIFT  4
 
 #define MAX30100_REG_LED_CONFIG_24MA           0x07
@@ -111,6 +113,12 @@ static const struct regmap_config max30100_regmap_config = {
        .volatile_reg = max30100_is_volatile_reg,
 };
 
+static const unsigned int max30100_led_current_mapping[] = {
+       4400, 7600, 11000, 14200, 17400,
+       20800, 24000, 27100, 30600, 33800,
+       37000, 40200, 43600, 46800, 50000
+};
+
 static const unsigned long max30100_scan_masks[] = {0x3, 0};
 
 static const struct iio_chan_spec max30100_channels[] = {
@@ -230,12 +238,13 @@ static irqreturn_t max30100_interrupt_handler(int irq, void *private)
 
        mutex_lock(&data->lock);
 
-       while (cnt-- || (cnt = max30100_fifo_count(data) > 0)) {
+       while (cnt || (cnt = max30100_fifo_count(data) > 0)) {
                ret = max30100_read_measurement(data);
                if (ret)
                        break;
 
                iio_push_to_buffers(data->indio_dev, data->buffer);
+               cnt--;
        }
 
        mutex_unlock(&data->lock);
@@ -243,15 +252,76 @@ static irqreturn_t max30100_interrupt_handler(int irq, void *private)
        return IRQ_HANDLED;
 }
 
+static int max30100_get_current_idx(unsigned int val, int *reg)
+{
+       int idx;
+
+       /* LED turned off */
+       if (val == 0) {
+               *reg = 0;
+               return 0;
+       }
+
+       for (idx = 0; idx < ARRAY_SIZE(max30100_led_current_mapping); idx++) {
+               if (max30100_led_current_mapping[idx] == val) {
+                       *reg = idx + 1;
+                       return 0;
+               }
+       }
+
+       return -EINVAL;
+}
+
+static int max30100_led_init(struct max30100_data *data)
+{
+       struct device *dev = &data->client->dev;
+       struct device_node *np = dev->of_node;
+       unsigned int val[2];
+       int reg, ret;
+
+       ret = of_property_read_u32_array(np, "maxim,led-current-microamp",
+                                       (unsigned int *) &val, 2);
+       if (ret) {
+               /* Default to 24 mA RED LED, 50 mA IR LED */
+               reg = (MAX30100_REG_LED_CONFIG_24MA <<
+                       MAX30100_REG_LED_CONFIG_RED_LED_SHIFT) |
+                       MAX30100_REG_LED_CONFIG_50MA;
+               dev_warn(dev, "no led-current-microamp set");
+
+               return regmap_write(data->regmap, MAX30100_REG_LED_CONFIG, reg);
+       }
+
+       /* RED LED current */
+       ret = max30100_get_current_idx(val[0], &reg);
+       if (ret) {
+               dev_err(dev, "invalid RED current setting %d", val[0]);
+               return ret;
+       }
+
+       ret = regmap_update_bits(data->regmap, MAX30100_REG_LED_CONFIG,
+               MAX30100_REG_LED_CONFIG_LED_MASK <<
+               MAX30100_REG_LED_CONFIG_RED_LED_SHIFT,
+               reg << MAX30100_REG_LED_CONFIG_RED_LED_SHIFT);
+       if (ret)
+               return ret;
+
+       /* IR LED current */
+       ret = max30100_get_current_idx(val[1], &reg);
+       if (ret) {
+               dev_err(dev, "invalid IR current setting %d", val[1]);
+               return ret;
+       }
+
+       return regmap_update_bits(data->regmap, MAX30100_REG_LED_CONFIG,
+               MAX30100_REG_LED_CONFIG_LED_MASK, reg);
+}
+
 static int max30100_chip_init(struct max30100_data *data)
 {
        int ret;
 
-       /* RED IR LED = 24mA, IR LED = 50mA */
-       ret = regmap_write(data->regmap, MAX30100_REG_LED_CONFIG,
-                               (MAX30100_REG_LED_CONFIG_24MA <<
-                                MAX30100_REG_LED_CONFIG_RED_LED_SHIFT) |
-                                MAX30100_REG_LED_CONFIG_50MA);
+       /* setup LED current settings */
+       ret = max30100_led_init(data);
        if (ret)
                return ret;