On Fri, 27 Nov 2020 at 15:55, Guenter Roeck <linux@xxxxxxxxxxxx> wrote:
>
> 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);
Thanks for the review. Those are all straightforward changes so I'll
make them and send a v2.
--
Paul Barker
Konsulko Group
