Re: [PATCH v3 2/2] hwmon: Support set_trips() of thermal device ops
From: Guenter Roeck <linux@roeck-us.net>
Date: 2021-06-21 20:30:52
Also in:
linux-hwmon, linux-tegra, lkml
On Mon, Jun 21, 2021 at 09:40:58PM +0300, Dmitry Osipenko wrote:
Support set_trips() callback of thermal device ops. This allows HWMON device to operatively notify thermal core about temperature changes, which is very handy to have in a case where HWMON sensor is used by CPU thermal zone that performs passive cooling and emergency shutdown on overheat. Thermal core will be able to react faster to temperature changes.
I think that warrants an explanation why it doesn't matter if the code doesn't really set any trip points.
quoted hunk ↗ jump to hunk
Signed-off-by: Dmitry Osipenko <digetx@gmail.com> --- drivers/hwmon/hwmon.c | 32 ++++++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+)diff --git a/drivers/hwmon/hwmon.c b/drivers/hwmon/hwmon.c index fd47ab4e6892..e74dc81e650d 100644 --- a/drivers/hwmon/hwmon.c +++ b/drivers/hwmon/hwmon.c@@ -153,8 +153,40 @@ static int hwmon_thermal_get_temp(void *data, int *temp) return 0; } +static int hwmon_thermal_set_trips(void *data, int low, int high) +{ + struct hwmon_thermal_data *tdata = data; + struct hwmon_device *hwdev = to_hwmon_device(tdata->dev); + const struct hwmon_chip_info *chip = hwdev->chip; + const struct hwmon_channel_info **info = chip->info; + unsigned int i; + + if (!chip->ops->write) + return 0; + + for (i = 1; info[i] && info[i]->type != hwmon_temp; i++) + continue;
Why start with index 1 ? While index 0 is commonly used for chip data, that is not mandatory.
+
+ if (info[i] && info[i]->config[tdata->index] & HWMON_T_MIN) {
+ int err = chip->ops->write(tdata->dev, hwmon_temp,
+ hwmon_temp_min, tdata->index, low);checkpatch will complain here because it expects an empty line after a declaration. Since err is used in multiple conditionals, I would suggest to declare it once in the function header.
+ if (err < 0 && err != -EOPNOTSUPP)
"< 0" is unnecessary.
+ return err;
+ }
+
+ if (info[i] && info[i]->config[tdata->index] & HWMON_T_MAX) {
+ int err = chip->ops->write(tdata->dev, hwmon_temp,
+ hwmon_temp_max, tdata->index, high);
+ if (err < 0 && err != -EOPNOTSUPP)"< 0" is unnecessary.
+ return err;
+ }
+
+ return 0;
+}
+
static const struct thermal_zone_of_device_ops hwmon_thermal_ops = {
.get_temp = hwmon_thermal_get_temp,
+ .set_trips = hwmon_thermal_set_trips,
};
static void hwmon_thermal_remove_sensor(void *data)