[PATCH linux v1 3/3] drivers: w1: add hwmon temp support for w1_therm

Jaghathiswari Rankappagounder Natarajan
2017-06-14T22:00:00Z

This change adds hwmon temp support for w1_therm.

Signed-off-by: Jaghathiswari Rankappagounder Natarajan <jaghu@google.com>
Change-Id: I66c0837d63b5a5839227319608eb8061b917f5fa
---
drivers/w1/slaves/w1_therm.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 44 insertions(+)

diff --git a/drivers/w1/slaves/w1_therm.c b/drivers/w1/slaves/w1_therm.c
index 88f4cc8c3908..dba2d21fa731 100644
--- a/drivers/w1/slaves/w1_therm.c
+++ b/drivers/w1/slaves/w1_therm.c
@@ -105,8 +105,12 @@ static ssize_t w1_slave_store(struct device *device,
static ssize_t w1_seq_show(struct device *device,
struct device_attribute *attr, char *buf);

+static ssize_t temp1_input_show(struct device *device,
+ struct device_attribute *attr, char *buf);
+
static DEVICE_ATTR_RW(w1_slave);
static DEVICE_ATTR_RO(w1_seq);
+static DEVICE_ATTR_RO(temp1_input);

static struct attribute *w1_therm_attrs[] = {
&dev_attr_w1_slave.attr,
@@ -118,19 +122,27 @@ static struct attribute *w1_ds28ea00_attrs[] = {
&dev_attr_w1_seq.attr,
NULL,
};
+static struct attribute *w1_therm_hwmon_attrs[] = {
+ &dev_attr_temp1_input.attr,
+ NULL,
+};
+
ATTRIBUTE_GROUPS(w1_therm);
ATTRIBUTE_GROUPS(w1_ds28ea00);
+ATTRIBUTE_GROUPS(w1_therm_hwmon);

static struct w1_family_ops w1_therm_fops = {
.add_slave = w1_therm_add_slave,
.remove_slave = w1_therm_remove_slave,
.groups = w1_therm_groups,
+ .hwmon_groups = w1_therm_hwmon_groups,
};

static struct w1_family_ops w1_ds28ea00_fops = {
.add_slave = w1_therm_add_slave,
.remove_slave = w1_therm_remove_slave,
.groups = w1_ds28ea00_groups,
+ .hwmon_groups = w1_therm_hwmon_groups,
};

static struct w1_family w1_therm_family_DS18S20 = {
@@ -559,6 +571,38 @@ static ssize_t w1_slave_show(struct device *device,
return ret;
}

+static ssize_t temp1_input_show(struct device *device,
+ struct device_attribute *attr, char *buf)
+{
+ 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));
+
+ 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;
+ }
+
+ ret = sprintf(buf, "%d\n",
+ w1_convert_temp(info.rom, sl->family->fid));
+
+dec_refcnt:
+ atomic_dec(THERM_REFCNT(family_data));
+ return ret;
+}
+
#define W1_42_CHAIN 0x99
#define W1_42_CHAIN_OFF 0x3C
#define W1_42_CHAIN_OFF_INV 0xC3