hwmon: (adt7475) Add support for inverting pwm output

Add a "adi,pwm-active-state" device-tree property to allow hardware
designs to use inverted logic on the PWM output.

Signed-off-by: Chris Packham <chris.packham@alliedtelesis.co.nz>
[groeck: dev_err -> dev_warn]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
This commit is contained in:
Chris Packham 2020-02-27 21:46:42 +13:00 committed by Guenter Roeck
parent 2ecff39791
commit 86da28eed4

View File

@ -1509,6 +1509,36 @@ static int load_attenuators(const struct i2c_client *client, int chip,
return 0;
}
static int adt7475_set_pwm_polarity(struct i2c_client *client)
{
u32 states[ADT7475_PWM_COUNT];
int ret, i;
u8 val;
ret = of_property_read_u32_array(client->dev.of_node,
"adi,pwm-active-state", states,
ARRAY_SIZE(states));
if (ret)
return ret;
for (i = 0; i < ADT7475_PWM_COUNT; i++) {
ret = adt7475_read(PWM_CONFIG_REG(i));
if (ret < 0)
return ret;
val = ret;
if (states[i])
val &= ~BIT(4);
else
val |= BIT(4);
ret = i2c_smbus_write_byte_data(client, PWM_CONFIG_REG(i), val);
if (ret)
return ret;
}
return 0;
}
static int adt7475_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
@ -1617,6 +1647,10 @@ static int adt7475_probe(struct i2c_client *client,
for (i = 0; i < ADT7475_PWM_COUNT; i++)
adt7475_read_pwm(client, i);
ret = adt7475_set_pwm_polarity(client);
if (ret && ret != -EINVAL)
dev_warn(&client->dev, "Error configuring pwm polarity\n");
/* Start monitoring */
switch (chip) {
case adt7475: