On Thu, Nov 26, 2020 at 05:44:08PM +0000, Paul Barker wrote:
> The pwm-fan driver is updated to use the recommended API.
>
> Signed-off-by: Paul Barker <pbarker@xxxxxxxxxxxx>
> ---
> drivers/hwmon/pwm-fan.c | 112 +++++++++++++++++++++++++---------------
> 1 file changed, 71 insertions(+), 41 deletions(-)
>
> diff --git a/drivers/hwmon/pwm-fan.c b/drivers/hwmon/pwm-fan.c
> index efe2764f42d3..c8a1d41d6f06 100644
> --- a/drivers/hwmon/pwm-fan.c
> +++ b/drivers/hwmon/pwm-fan.c
> @@ -8,7 +8,6 @@
> */
>
> #include <linux/hwmon.h>
> -#include <linux/hwmon-sysfs.h>
> #include <linux/interrupt.h>
> #include <linux/module.h>
> #include <linux/mutex.h>
> @@ -39,6 +38,28 @@ struct pwm_fan_ctx {
> unsigned int pwm_fan_max_state;
> unsigned int *pwm_fan_cooling_levels;
> struct thermal_cooling_device *cdev;
> +
> + struct hwmon_chip_info info;
> +};
> +
> +static const u32 pwm_fan_channel_config_pwm[] = {
> + HWMON_PWM_INPUT,
> + 0
> +};
> +
> +static const struct hwmon_channel_info pwm_fan_channel_pwm = {
> + .type = hwmon_pwm,
> + .config = pwm_fan_channel_config_pwm,
> +};
> +
> +static const u32 pwm_fan_channel_config_fan[] = {
> + HWMON_F_INPUT,
> + 0
> +};
> +
> +static const struct hwmon_channel_info pwm_fan_channel_fan = {
> + .type = hwmon_fan,
> + .config = pwm_fan_channel_config_fan,
> };
In general I'd suggest to use the HWMON_CHANNEL_INFO() macro instead,
but I think this is to prepare for a dynamic number of channels.
With that in mind, it is ok.
>
> /* This handler assumes self resetting edge triggered interrupt. */
> @@ -103,14 +124,14 @@ static void pwm_fan_update_state(struct pwm_fan_ctx *ctx, unsigned long pwm)
> ctx->pwm_fan_state = i;
> }
>
> -static ssize_t pwm_store(struct device *dev, struct device_attribute *attr,
> - const char *buf, size_t count)
> +static int pwm_fan_write(struct device *dev, enum hwmon_sensor_types type,
> + u32 attr, int channel, long val)
> {
> struct pwm_fan_ctx *ctx = dev_get_drvdata(dev);
> - unsigned long pwm;
> + unsigned long pwm = val;
> int ret;
>
> - if (kstrtoul(buf, 10, &pwm) || pwm > MAX_PWM)
> + if (pwm > MAX_PWM)
> return -EINVAL;
This happens to catch negative values, but it is odd and somewhat difficult
to review and understand. I would suggest to drop the pwm variable and use
if (val < 0 || val > MAX_PWM)
return -EINVAL;
instead.
>
> ret = __set_pwm(ctx, pwm);
> @@ -118,55 +139,50 @@ static ssize_t pwm_store(struct device *dev, struct device_attribute *attr,
> return ret;
>
> pwm_fan_update_state(ctx, pwm);
> - return count;
> + return 0;
> }
>
> -static ssize_t pwm_show(struct device *dev, struct device_attribute *attr,
> - char *buf)
> +static int pwm_fan_read(struct device *dev, enum hwmon_sensor_types type,
> + u32 attr, int channel, long *val)
> {
> struct pwm_fan_ctx *ctx = dev_get_drvdata(dev);
>
> - return sprintf(buf, "%u\n", ctx->pwm_value);
> -}
> + switch (type) {
> + case hwmon_pwm:
> + *val = ctx->pwm_value;
> + return 0;
>
> -static ssize_t rpm_show(struct device *dev,
> - struct device_attribute *attr, char *buf)
> -{
> - struct pwm_fan_ctx *ctx = dev_get_drvdata(dev);
> + case hwmon_fan:
> + *val = ctx->rpm;
> + return 0;
>
> - return sprintf(buf, "%u\n", ctx->rpm);
> + default:
> + return -EINVAL;
return -EOPNOTSUPP;
> + }
> }
>
> -static SENSOR_DEVICE_ATTR_RW(pwm1, pwm, 0);
> -static SENSOR_DEVICE_ATTR_RO(fan1_input, rpm, 0);
> +static umode_t pwm_fan_is_visible(const void *data,
> + enum hwmon_sensor_types type,
> + u32 attr, int channel)
> +{
> + struct pwm_fan_ctx *ctx = (struct pwm_fan_ctx *)data;
>
> -static struct attribute *pwm_fan_attrs[] = {
> - &sensor_dev_attr_pwm1.dev_attr.attr,
> - &sensor_dev_attr_fan1_input.dev_attr.attr,
> - NULL,
> -};
> + switch (type) {
> + case hwmon_pwm:
> + return 0644;
>
> -static umode_t pwm_fan_attrs_visible(struct kobject *kobj, struct attribute *a,
> - int n)
> -{
> - struct device *dev = container_of(kobj, struct device, kobj);
> - struct pwm_fan_ctx *ctx = dev_get_drvdata(dev);
> + case hwmon_fan:
> + return 0444;
>
> - /* Hide fan_input in case no interrupt is available */
> - if (n == 1 && ctx->irq <= 0)
> + default:
> return 0;
> -
> - return a->mode;
> + }
> }
>
> -static const struct attribute_group pwm_fan_group = {
> - .attrs = pwm_fan_attrs,
> - .is_visible = pwm_fan_attrs_visible,
> -};
> -
> -static const struct attribute_group *pwm_fan_groups[] = {
> - &pwm_fan_group,
> - NULL,
> +static const struct hwmon_ops pwm_fan_hwmon_ops = {
> + .is_visible = pwm_fan_is_visible,
> + .read = pwm_fan_read,
> + .write = pwm_fan_write,
> };
>
> /* thermal cooling device callbacks */
> @@ -287,6 +303,8 @@ static int pwm_fan_probe(struct platform_device *pdev)
> int ret;
> struct pwm_state state = { };
> int tach_count;
> + size_t sz;
> + const struct hwmon_channel_info **channels;
>
> ctx = devm_kzalloc(dev, sizeof(*ctx), GFP_KERNEL);
> if (!ctx)
> @@ -340,6 +358,13 @@ static int pwm_fan_probe(struct platform_device *pdev)
> return dev_err_probe(dev, tach_count,
> "Could not get number of fan tachometer inputs\n");
>
> + sz = (2 + tach_count) * sizeof(struct hwmon_channel_info *);
> + channels = devm_kzalloc(dev, sz, GFP_KERNEL);
devm_kcalloc() is preferred.
channels = devm_kcalloc(dev, tach_count + 2,
sizeof(struct hwmon_channel_info *), GFP_KERNEL);
> + if (!channels)
> + return -ENOMEM;
> +
> + channels[0] = &pwm_fan_channel_pwm;
> +
> if (tach_count > 0) {
> u32 ppr = 2;
>
> @@ -371,10 +396,15 @@ static int pwm_fan_probe(struct platform_device *pdev)
>
> ctx->sample_start = ktime_get();
> mod_timer(&ctx->rpm_timer, jiffies + HZ);
> +
> + channels[1] = &pwm_fan_channel_fan;
> }
>
> - hwmon = devm_hwmon_device_register_with_groups(dev, "pwmfan",
> - ctx, pwm_fan_groups);
> + ctx->info.ops = &pwm_fan_hwmon_ops;
> + ctx->info.info = channels;
> +
> + hwmon = devm_hwmon_device_register_with_info(dev, "pwmfan",
> + ctx, &ctx->info, NULL);
> if (IS_ERR(hwmon)) {
> dev_err(dev, "Failed to register hwmon device\n");
> return PTR_ERR(hwmon);
