This change adds hwmon temp support for w1_therm.
Signed-off-by: Jaghathiswari Rankappagounder Natarajan <ja...@google.com>
Acked-by: Evgeniy Polyakov <z...@ioremap.net>
---
v2
- make changes to support hwmon_device_register_with_info mentioned by Guenter.
drivers/w1/slaves/w1_therm.c | 117 +++++++++++++++++++++++++++++++++++++++++++
1 file changed, 117 insertions(+)
diff --git a/drivers/w1/slaves/w1_therm.c b/drivers/w1/slaves/w1_therm.c
index 88f4cc8c3908..147f9dfa13de 100644
--- a/drivers/w1/slaves/w1_therm.c
+++ b/drivers/w1/slaves/w1_therm.c
@@ -29,6 +29,7 @@
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/delay.h>
+#include <linux/hwmon.h>
#include "../w1.h"
#include "../w1_int.h"
@@ -118,19 +119,61 @@ static struct attribute *w1_ds28ea00_attrs[] = {
&dev_attr_w1_seq.attr,
NULL,
};
+
ATTRIBUTE_GROUPS(w1_therm);
ATTRIBUTE_GROUPS(w1_ds28ea00);
+static umode_t w1_is_visible(const void *_data,
+ enum hwmon_sensor_types type,
+ u32 attr, int channel);
+
+static int w1_read_temp(struct device *dev, u32 attr, int channel,
+ long *val);
+
+static int w1_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val);
+
+static int w1_write(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long val);
+
+static const u32 w1_temp_config[] = {
+ HWMON_T_INPUT,
+ 0
+};
+
+static const struct hwmon_channel_info w1_temp = {
+ .type = hwmon_temp,
+ .config = w1_temp_config,
+};
+
+static const struct hwmon_channel_info *w1_info[] = {
+ &w1_temp,
+ NULL
+};
+
+static const struct hwmon_ops w1_hwmon_ops = {
+ .is_visible = w1_is_visible,
+ .read = w1_read,
+ .write = w1_write,
+};
+
+static const struct hwmon_chip_info w1_chip_info = {
+ .ops = &w1_hwmon_ops,
+ .info = w1_info,
+};
+
static struct w1_family_ops w1_therm_fops = {
.add_slave = w1_therm_add_slave,
.remove_slave = w1_therm_remove_slave,
.groups = w1_therm_groups,
+ .chip_info = &w1_chip_info,
};
static struct w1_family_ops w1_ds28ea00_fops = {
.add_slave = w1_therm_add_slave,
.remove_slave = w1_therm_remove_slave,
.groups = w1_ds28ea00_groups,
+ .chip_info = &w1_chip_info,
};
static struct w1_family w1_therm_family_DS18S20 = {
@@ -559,6 +602,80 @@ static ssize_t w1_slave_show(struct device *device,
return ret;
}
+static int w1_read_temp(struct device *device, u32 attr, int channel,
+ long *val)
+{
+ struct w1_slave *sl = dev_get_drvdata(device);
+ u8 *family_data = sl->family_data;
+ struct therm_info info;
+ int ret;
+
+ if (!sl->family_data)
+ return -ENODEV;
+
+ /* prevent the slave from going away in sleep */
+ atomic_inc(THERM_REFCNT(family_data));
+
+ switch (attr) {
+ case hwmon_temp_input:
+ ret = read_therm(device, sl, &info);
+ if (ret)
+ goto dec_refcnt;
+
+ if (!info.verdict) {
+ dev_warn(device, "Read failed CRC check\n");
+ ret = -EIO;
+ goto dec_refcnt;
+ }
+
+ *val = w1_convert_temp(info.rom, sl->family->fid);
+ ret = 0;
+ break;
+ default:
+ ret = -EOPNOTSUPP;
+ break;
+ }
+
+dec_refcnt:
+ atomic_dec(THERM_REFCNT(family_data));
+ return ret;
+}
+
+static umode_t w1_is_visible(const void *_data, enum hwmon_sensor_types type,
+ u32 attr, int channel)
+{
+ umode_t mode = 0444;
+
+ switch (attr) {
+ case hwmon_temp_input:
+ break;
+ default:
+ mode = 0;
+ break;
+ }
+ return mode;
+}
+
+static int w1_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val)
+{
+ switch (type) {
+ case hwmon_temp:
+ return w1_read_temp(dev, attr, channel, val);
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static int w1_write(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long val)
+{
+ switch (type) {
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
#define W1_42_CHAIN 0x99
#define W1_42_CHAIN_OFF 0x3C
#define W1_42_CHAIN_OFF_INV 0xC3
--
2.13.2.932.g7449e964c-goog
