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Diffstat (limited to 'drivers/hwmon/max31827.c')
-rw-r--r--drivers/hwmon/max31827.c273
1 files changed, 242 insertions, 31 deletions
diff --git a/drivers/hwmon/max31827.c b/drivers/hwmon/max31827.c
index a1ce651456..4a8c3e37c5 100644
--- a/drivers/hwmon/max31827.c
+++ b/drivers/hwmon/max31827.c
@@ -11,6 +11,7 @@
#include <linux/hwmon.h>
#include <linux/i2c.h>
#include <linux/mutex.h>
+#include <linux/of_device.h>
#include <linux/regmap.h>
#include <linux/regulator/consumer.h>
@@ -23,15 +24,30 @@
#define MAX31827_CONFIGURATION_1SHOT_MASK BIT(0)
#define MAX31827_CONFIGURATION_CNV_RATE_MASK GENMASK(3, 1)
+#define MAX31827_CONFIGURATION_TIMEOUT_MASK BIT(5)
+#define MAX31827_CONFIGURATION_RESOLUTION_MASK GENMASK(7, 6)
+#define MAX31827_CONFIGURATION_ALRM_POL_MASK BIT(8)
+#define MAX31827_CONFIGURATION_COMP_INT_MASK BIT(9)
+#define MAX31827_CONFIGURATION_FLT_Q_MASK GENMASK(11, 10)
#define MAX31827_CONFIGURATION_U_TEMP_STAT_MASK BIT(14)
#define MAX31827_CONFIGURATION_O_TEMP_STAT_MASK BIT(15)
+#define MAX31827_ALRM_POL_LOW 0x0
+#define MAX31827_ALRM_POL_HIGH 0x1
+#define MAX31827_FLT_Q_1 0x0
+#define MAX31827_FLT_Q_4 0x2
+
+#define MAX31827_8_BIT_CNV_TIME 9
+#define MAX31827_9_BIT_CNV_TIME 18
+#define MAX31827_10_BIT_CNV_TIME 35
#define MAX31827_12_BIT_CNV_TIME 140
#define MAX31827_16_BIT_TO_M_DGR(x) (sign_extend32(x, 15) * 1000 / 16)
#define MAX31827_M_DGR_TO_16_BIT(x) (((x) << 4) / 1000)
#define MAX31827_DEVICE_ENABLE(x) ((x) ? 0xA : 0x0)
+enum chips { max31827 = 1, max31828, max31829 };
+
enum max31827_cnv {
MAX31827_CNV_1_DIV_64_HZ = 1,
MAX31827_CNV_1_DIV_32_HZ,
@@ -52,6 +68,27 @@ static const u16 max31827_conversions[] = {
[MAX31827_CNV_8_HZ] = 125,
};
+enum max31827_resolution {
+ MAX31827_RES_8_BIT = 0,
+ MAX31827_RES_9_BIT,
+ MAX31827_RES_10_BIT,
+ MAX31827_RES_12_BIT,
+};
+
+static const u16 max31827_resolutions[] = {
+ [MAX31827_RES_8_BIT] = 1000,
+ [MAX31827_RES_9_BIT] = 500,
+ [MAX31827_RES_10_BIT] = 250,
+ [MAX31827_RES_12_BIT] = 62,
+};
+
+static const u16 max31827_conv_times[] = {
+ [MAX31827_RES_8_BIT] = MAX31827_8_BIT_CNV_TIME,
+ [MAX31827_RES_9_BIT] = MAX31827_9_BIT_CNV_TIME,
+ [MAX31827_RES_10_BIT] = MAX31827_10_BIT_CNV_TIME,
+ [MAX31827_RES_12_BIT] = MAX31827_12_BIT_CNV_TIME,
+};
+
struct max31827_state {
/*
* Prevent simultaneous access to the i2c client.
@@ -59,6 +96,8 @@ struct max31827_state {
struct mutex lock;
struct regmap *regmap;
bool enable;
+ unsigned int resolution;
+ unsigned int update_interval;
};
static const struct regmap_config max31827_regmap = {
@@ -68,16 +107,16 @@ static const struct regmap_config max31827_regmap = {
};
static int shutdown_write(struct max31827_state *st, unsigned int reg,
- unsigned int val)
+ unsigned int mask, unsigned int val)
{
unsigned int cfg;
unsigned int cnv_rate;
int ret;
/*
- * Before the Temperature Threshold Alarm and Alarm Hysteresis Threshold
- * register values are changed over I2C, the part must be in shutdown
- * mode.
+ * Before the Temperature Threshold Alarm, Alarm Hysteresis Threshold
+ * and Resolution bits from Configuration register are changed over I2C,
+ * the part must be in shutdown mode.
*
* Mutex is used to ensure, that some other process doesn't change the
* configuration register.
@@ -85,7 +124,10 @@ static int shutdown_write(struct max31827_state *st, unsigned int reg,
mutex_lock(&st->lock);
if (!st->enable) {
- ret = regmap_write(st->regmap, reg, val);
+ if (!mask)
+ ret = regmap_write(st->regmap, reg, val);
+ else
+ ret = regmap_update_bits(st->regmap, reg, mask, val);
goto unlock;
}
@@ -100,7 +142,11 @@ static int shutdown_write(struct max31827_state *st, unsigned int reg,
if (ret)
goto unlock;
- ret = regmap_write(st->regmap, reg, val);
+ if (!mask)
+ ret = regmap_write(st->regmap, reg, val);
+ else
+ ret = regmap_update_bits(st->regmap, reg, mask, val);
+
if (ret)
goto unlock;
@@ -118,7 +164,7 @@ static int write_alarm_val(struct max31827_state *st, unsigned int reg,
{
val = MAX31827_M_DGR_TO_16_BIT(val);
- return shutdown_write(st, reg, val);
+ return shutdown_write(st, reg, 0, val);
}
static umode_t max31827_is_visible(const void *state,
@@ -188,9 +234,18 @@ static int max31827_read(struct device *dev, enum hwmon_sensor_types type,
mutex_unlock(&st->lock);
return ret;
}
-
- msleep(MAX31827_12_BIT_CNV_TIME);
+ msleep(max31827_conv_times[st->resolution]);
}
+
+ /*
+ * For 12-bit resolution the conversion time is 140 ms,
+ * thus an additional 15 ms is needed to complete the
+ * conversion: 125 ms + 15 ms = 140 ms
+ */
+ if (max31827_resolutions[st->resolution] == 12 &&
+ st->update_interval == 125)
+ usleep_range(15000, 20000);
+
ret = regmap_read(st->regmap, MAX31827_T_REG, &uval);
mutex_unlock(&st->lock);
@@ -341,17 +396,20 @@ static int max31827_write(struct device *dev, enum hwmon_sensor_types type,
val < max31827_conversions[res])
res++;
- if (res == ARRAY_SIZE(max31827_conversions) ||
- val != max31827_conversions[res])
- return -EINVAL;
+ if (res == ARRAY_SIZE(max31827_conversions))
+ res = ARRAY_SIZE(max31827_conversions) - 1;
res = FIELD_PREP(MAX31827_CONFIGURATION_CNV_RATE_MASK,
res);
- return regmap_update_bits(st->regmap,
- MAX31827_CONFIGURATION_REG,
- MAX31827_CONFIGURATION_CNV_RATE_MASK,
- res);
+ ret = regmap_update_bits(st->regmap,
+ MAX31827_CONFIGURATION_REG,
+ MAX31827_CONFIGURATION_CNV_RATE_MASK,
+ res);
+ if (ret)
+ return ret;
+
+ st->update_interval = val;
}
break;
@@ -359,17 +417,165 @@ static int max31827_write(struct device *dev, enum hwmon_sensor_types type,
return -EOPNOTSUPP;
}
- return -EOPNOTSUPP;
+ return 0;
+}
+
+static ssize_t temp1_resolution_show(struct device *dev,
+ struct device_attribute *devattr,
+ char *buf)
+{
+ struct max31827_state *st = dev_get_drvdata(dev);
+ unsigned int val;
+ int ret;
+
+ ret = regmap_read(st->regmap, MAX31827_CONFIGURATION_REG, &val);
+ if (ret)
+ return ret;
+
+ val = FIELD_GET(MAX31827_CONFIGURATION_RESOLUTION_MASK, val);
+
+ return scnprintf(buf, PAGE_SIZE, "%u\n", max31827_resolutions[val]);
}
-static int max31827_init_client(struct max31827_state *st)
+static ssize_t temp1_resolution_store(struct device *dev,
+ struct device_attribute *devattr,
+ const char *buf, size_t count)
{
+ struct max31827_state *st = dev_get_drvdata(dev);
+ unsigned int idx = 0;
+ unsigned int val;
+ int ret;
+
+ ret = kstrtouint(buf, 10, &val);
+ if (ret)
+ return ret;
+
+ /*
+ * Convert the desired resolution into register
+ * bits. idx is already initialized with 0.
+ *
+ * This was inspired by lm73 driver.
+ */
+ while (idx < ARRAY_SIZE(max31827_resolutions) &&
+ val < max31827_resolutions[idx])
+ idx++;
+
+ if (idx == ARRAY_SIZE(max31827_resolutions))
+ idx = ARRAY_SIZE(max31827_resolutions) - 1;
+
+ st->resolution = idx;
+
+ ret = shutdown_write(st, MAX31827_CONFIGURATION_REG,
+ MAX31827_CONFIGURATION_RESOLUTION_MASK,
+ FIELD_PREP(MAX31827_CONFIGURATION_RESOLUTION_MASK,
+ idx));
+
+ return ret ? ret : count;
+}
+
+static DEVICE_ATTR_RW(temp1_resolution);
+
+static struct attribute *max31827_attrs[] = {
+ &dev_attr_temp1_resolution.attr,
+ NULL
+};
+ATTRIBUTE_GROUPS(max31827);
+
+static const struct i2c_device_id max31827_i2c_ids[] = {
+ { "max31827", max31827 },
+ { "max31828", max31828 },
+ { "max31829", max31829 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, max31827_i2c_ids);
+
+static int max31827_init_client(struct max31827_state *st,
+ struct device *dev)
+{
+ struct fwnode_handle *fwnode;
+ unsigned int res = 0;
+ u32 data, lsb_idx;
+ enum chips type;
+ bool prop;
+ int ret;
+
+ fwnode = dev_fwnode(dev);
+
st->enable = true;
+ res |= MAX31827_DEVICE_ENABLE(1);
- return regmap_update_bits(st->regmap, MAX31827_CONFIGURATION_REG,
- MAX31827_CONFIGURATION_1SHOT_MASK |
- MAX31827_CONFIGURATION_CNV_RATE_MASK,
- MAX31827_DEVICE_ENABLE(1));
+ res |= MAX31827_CONFIGURATION_RESOLUTION_MASK;
+
+ prop = fwnode_property_read_bool(fwnode, "adi,comp-int");
+ res |= FIELD_PREP(MAX31827_CONFIGURATION_COMP_INT_MASK, prop);
+
+ prop = fwnode_property_read_bool(fwnode, "adi,timeout-enable");
+ res |= FIELD_PREP(MAX31827_CONFIGURATION_TIMEOUT_MASK, !prop);
+
+ type = (enum chips)(uintptr_t)device_get_match_data(dev);
+
+ if (fwnode_property_present(fwnode, "adi,alarm-pol")) {
+ ret = fwnode_property_read_u32(fwnode, "adi,alarm-pol", &data);
+ if (ret)
+ return ret;
+
+ res |= FIELD_PREP(MAX31827_CONFIGURATION_ALRM_POL_MASK, !!data);
+ } else {
+ /*
+ * Set default value.
+ */
+ switch (type) {
+ case max31827:
+ case max31828:
+ res |= FIELD_PREP(MAX31827_CONFIGURATION_ALRM_POL_MASK,
+ MAX31827_ALRM_POL_LOW);
+ break;
+ case max31829:
+ res |= FIELD_PREP(MAX31827_CONFIGURATION_ALRM_POL_MASK,
+ MAX31827_ALRM_POL_HIGH);
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+ }
+
+ if (fwnode_property_present(fwnode, "adi,fault-q")) {
+ ret = fwnode_property_read_u32(fwnode, "adi,fault-q", &data);
+ if (ret)
+ return ret;
+
+ /*
+ * Convert the desired fault queue into register bits.
+ */
+ if (data != 0)
+ lsb_idx = __ffs(data);
+
+ if (hweight32(data) != 1 || lsb_idx > 4) {
+ dev_err(dev, "Invalid data in adi,fault-q\n");
+ return -EINVAL;
+ }
+
+ res |= FIELD_PREP(MAX31827_CONFIGURATION_FLT_Q_MASK, lsb_idx);
+ } else {
+ /*
+ * Set default value.
+ */
+ switch (type) {
+ case max31827:
+ res |= FIELD_PREP(MAX31827_CONFIGURATION_FLT_Q_MASK,
+ MAX31827_FLT_Q_1);
+ break;
+ case max31828:
+ case max31829:
+ res |= FIELD_PREP(MAX31827_CONFIGURATION_FLT_Q_MASK,
+ MAX31827_FLT_Q_4);
+ break;
+ default:
+ return -EOPNOTSUPP;
+ }
+ }
+
+ return regmap_write(st->regmap, MAX31827_CONFIGURATION_REG, res);
}
static const struct hwmon_channel_info *max31827_info[] = {
@@ -417,25 +623,30 @@ static int max31827_probe(struct i2c_client *client)
if (err)
return dev_err_probe(dev, err, "failed to enable regulator\n");
- err = max31827_init_client(st);
+ err = max31827_init_client(st, dev);
if (err)
return err;
hwmon_dev = devm_hwmon_device_register_with_info(dev, client->name, st,
&max31827_chip_info,
- NULL);
+ max31827_groups);
return PTR_ERR_OR_ZERO(hwmon_dev);
}
-static const struct i2c_device_id max31827_i2c_ids[] = {
- { "max31827", 0 },
- { }
-};
-MODULE_DEVICE_TABLE(i2c, max31827_i2c_ids);
-
static const struct of_device_id max31827_of_match[] = {
- { .compatible = "adi,max31827" },
+ {
+ .compatible = "adi,max31827",
+ .data = (void *)max31827
+ },
+ {
+ .compatible = "adi,max31828",
+ .data = (void *)max31828
+ },
+ {
+ .compatible = "adi,max31829",
+ .data = (void *)max31829
+ },
{ }
};
MODULE_DEVICE_TABLE(of, max31827_of_match);