diff options
Diffstat (limited to 'drivers/hwmon/amc6821.c')
| -rw-r--r-- | drivers/hwmon/amc6821.c | 45 |
1 files changed, 41 insertions, 4 deletions
diff --git a/drivers/hwmon/amc6821.c b/drivers/hwmon/amc6821.c index 9b02b304c2f5..9c55d23bae0d 100644 --- a/drivers/hwmon/amc6821.c +++ b/drivers/hwmon/amc6821.c @@ -18,6 +18,10 @@ #include <linux/hwmon-sysfs.h> #include <linux/err.h> #include <linux/mutex.h> +#include <linux/of_platform.h> +#include <linux/pwm.h> + +#include <dt-bindings/pwm/pwm.h> /* * Addresses to scan. @@ -30,7 +34,7 @@ static const unsigned short normal_i2c[] = {0x18, 0x19, 0x1a, 0x2c, 0x2d, 0x2e, * Insmod parameters */ -static int pwminv; /*Inverted PWM output. */ +static int pwminv = -1; /*Inverted PWM output. */ module_param(pwminv, int, 0444); static int init = 1; /*Power-on initialization.*/ @@ -814,7 +818,40 @@ static int amc6821_detect( return 0; } -static int amc6821_init_client(struct i2c_client *client) +static enum pwm_polarity amc6821_pwm_polarity(struct i2c_client *client) +{ + enum pwm_polarity polarity = PWM_POLARITY_NORMAL; + struct of_phandle_args args; + struct device_node *fan_np; + + /* + * For backward compatibility, the pwminv module parameter takes + * always the precedence over any other device description + */ + if (pwminv == 0) + return PWM_POLARITY_NORMAL; + if (pwminv > 0) + return PWM_POLARITY_INVERSED; + + fan_np = of_get_child_by_name(client->dev.of_node, "fan"); + if (!fan_np) + return PWM_POLARITY_NORMAL; + + if (of_parse_phandle_with_args(fan_np, "pwms", "#pwm-cells", 0, &args)) + goto out; + of_node_put(args.np); + + if (args.args_count != 2) + goto out; + + if (args.args[1] & PWM_POLARITY_INVERTED) + polarity = PWM_POLARITY_INVERSED; +out: + of_node_put(fan_np); + return polarity; +} + +static int amc6821_init_client(struct i2c_client *client, struct amc6821_data *data) { int config; int err = -EIO; @@ -885,7 +922,7 @@ static int amc6821_init_client(struct i2c_client *client) config &= ~AMC6821_CONF1_THERMOVIE; config &= ~AMC6821_CONF1_FANIE; config |= AMC6821_CONF1_START; - if (pwminv) + if (amc6821_pwm_polarity(client) == PWM_POLARITY_INVERSED) config |= AMC6821_CONF1_PWMINV; else config &= ~AMC6821_CONF1_PWMINV; @@ -917,7 +954,7 @@ static int amc6821_probe(struct i2c_client *client) /* * Initialize the amc6821 chip */ - err = amc6821_init_client(client); + err = amc6821_init_client(client, data); if (err) return err; |