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path: root/drivers/hwmon/dell-smm-hwmon.c
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Diffstat (limited to 'drivers/hwmon/dell-smm-hwmon.c')
-rw-r--r--drivers/hwmon/dell-smm-hwmon.c147
1 files changed, 115 insertions, 32 deletions
diff --git a/drivers/hwmon/dell-smm-hwmon.c b/drivers/hwmon/dell-smm-hwmon.c
index 84cb1ede7bc0..071aa6f4e109 100644
--- a/drivers/hwmon/dell-smm-hwmon.c
+++ b/drivers/hwmon/dell-smm-hwmon.c
@@ -21,14 +21,17 @@
#include <linux/errno.h>
#include <linux/hwmon.h>
#include <linux/init.h>
+#include <linux/kconfig.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <linux/platform_device.h>
#include <linux/proc_fs.h>
#include <linux/seq_file.h>
-#include <linux/string.h>
+#include <linux/slab.h>
#include <linux/smp.h>
+#include <linux/string.h>
+#include <linux/thermal.h>
#include <linux/types.h>
#include <linux/uaccess.h>
@@ -46,8 +49,11 @@
#define I8K_SMM_GET_DELL_SIG1 0xfea3
#define I8K_SMM_GET_DELL_SIG2 0xffa3
+/* in usecs */
+#define DELL_SMM_MAX_DURATION 250000
+
#define I8K_FAN_MULT 30
-#define I8K_FAN_MAX_RPM 30000
+#define I8K_FAN_RPM_THRESHOLD 1000
#define I8K_MAX_TEMP 127
#define I8K_FN_NONE 0x00
@@ -80,6 +86,11 @@ struct dell_smm_data {
int *fan_nominal_speed[DELL_SMM_NO_FANS];
};
+struct dell_smm_cooling_data {
+ u8 fan_num;
+ struct dell_smm_data *data;
+};
+
MODULE_AUTHOR("Massimo Dal Zotto (dz@debian.org)");
MODULE_AUTHOR("Pali Rohár <pali@kernel.org>");
MODULE_DESCRIPTION("Dell laptop SMM BIOS hwmon driver");
@@ -231,6 +242,9 @@ static int i8k_smm_func(void *par)
pr_debug("smm(0x%.4x 0x%.4x) = 0x%.4x (took %7lld usecs)\n", eax, ebx,
(rc ? 0xffff : regs->eax & 0xffff), duration);
+ if (duration > DELL_SMM_MAX_DURATION)
+ pr_warn_once("SMM call took %lld usecs!\n", duration);
+
return rc;
}
@@ -318,7 +332,7 @@ static int __init i8k_get_fan_nominal_speed(const struct dell_smm_data *data, u8
if (data->disallow_fan_support)
return -EINVAL;
- return i8k_smm(&regs) ? : (regs.eax & 0xffff) * data->i8k_fan_mult;
+ return i8k_smm(&regs) ? : (regs.eax & 0xffff);
}
/*
@@ -638,9 +652,50 @@ static void __init i8k_init_procfs(struct device *dev)
#endif
-/*
- * Hwmon interface
- */
+static int dell_smm_get_max_state(struct thermal_cooling_device *dev, unsigned long *state)
+{
+ struct dell_smm_cooling_data *cdata = dev->devdata;
+
+ *state = cdata->data->i8k_fan_max;
+
+ return 0;
+}
+
+static int dell_smm_get_cur_state(struct thermal_cooling_device *dev, unsigned long *state)
+{
+ struct dell_smm_cooling_data *cdata = dev->devdata;
+ int ret;
+
+ ret = i8k_get_fan_status(cdata->data, cdata->fan_num);
+ if (ret < 0)
+ return ret;
+
+ *state = ret;
+
+ return 0;
+}
+
+static int dell_smm_set_cur_state(struct thermal_cooling_device *dev, unsigned long state)
+{
+ struct dell_smm_cooling_data *cdata = dev->devdata;
+ struct dell_smm_data *data = cdata->data;
+ int ret;
+
+ if (state > data->i8k_fan_max)
+ return -EINVAL;
+
+ mutex_lock(&data->i8k_mutex);
+ ret = i8k_set_fan(data, cdata->fan_num, (int)state);
+ mutex_unlock(&data->i8k_mutex);
+
+ return ret;
+}
+
+static const struct thermal_cooling_device_ops dell_smm_cooling_ops = {
+ .get_max_state = dell_smm_get_max_state,
+ .get_cur_state = dell_smm_get_cur_state,
+ .set_cur_state = dell_smm_set_cur_state,
+};
static umode_t dell_smm_is_visible(const void *drvdata, enum hwmon_sensor_types type, u32 attr,
int channel)
@@ -727,6 +782,7 @@ static int dell_smm_read(struct device *dev, enum hwmon_sensor_types type, u32 a
long *val)
{
struct dell_smm_data *data = dev_get_drvdata(dev);
+ int mult = data->i8k_fan_mult;
int ret;
switch (type) {
@@ -755,11 +811,11 @@ static int dell_smm_read(struct device *dev, enum hwmon_sensor_types type, u32 a
return 0;
case hwmon_fan_min:
- *val = data->fan_nominal_speed[channel][0];
+ *val = data->fan_nominal_speed[channel][0] * mult;
return 0;
case hwmon_fan_max:
- *val = data->fan_nominal_speed[channel][data->i8k_fan_max];
+ *val = data->fan_nominal_speed[channel][data->i8k_fan_max] * mult;
return 0;
case hwmon_fan_target:
@@ -770,7 +826,7 @@ static int dell_smm_read(struct device *dev, enum hwmon_sensor_types type, u32 a
if (ret > data->i8k_fan_max)
ret = data->i8k_fan_max;
- *val = data->fan_nominal_speed[channel][ret];
+ *val = data->fan_nominal_speed[channel][ret] * mult;
return 0;
default:
@@ -941,6 +997,37 @@ static const struct hwmon_chip_info dell_smm_chip_info = {
.info = dell_smm_info,
};
+static int __init dell_smm_init_cdev(struct device *dev, u8 fan_num)
+{
+ struct dell_smm_data *data = dev_get_drvdata(dev);
+ struct thermal_cooling_device *cdev;
+ struct dell_smm_cooling_data *cdata;
+ int ret = 0;
+ char *name;
+
+ name = kasprintf(GFP_KERNEL, "dell-smm-fan%u", fan_num + 1);
+ if (!name)
+ return -ENOMEM;
+
+ cdata = devm_kmalloc(dev, sizeof(*cdata), GFP_KERNEL);
+ if (cdata) {
+ cdata->fan_num = fan_num;
+ cdata->data = data;
+ cdev = devm_thermal_of_cooling_device_register(dev, NULL, name, cdata,
+ &dell_smm_cooling_ops);
+ if (IS_ERR(cdev)) {
+ devm_kfree(dev, cdata);
+ ret = PTR_ERR(cdev);
+ }
+ } else {
+ ret = -ENOMEM;
+ }
+
+ kfree(name);
+
+ return ret;
+}
+
static int __init dell_smm_init_hwmon(struct device *dev)
{
struct dell_smm_data *data = dev_get_drvdata(dev);
@@ -967,6 +1054,15 @@ static int __init dell_smm_init_hwmon(struct device *dev)
continue;
data->fan[i] = true;
+
+ /* the cooling device is not critical, ignore failures */
+ if (IS_REACHABLE(CONFIG_THERMAL)) {
+ err = dell_smm_init_cdev(dev, i);
+ if (err < 0)
+ dev_warn(dev, "Failed to register cooling device for fan %u\n",
+ i + 1);
+ }
+
data->fan_nominal_speed[i] = devm_kmalloc_array(dev, data->i8k_fan_max + 1,
sizeof(*data->fan_nominal_speed[i]),
GFP_KERNEL);
@@ -982,6 +1078,13 @@ static int __init dell_smm_init_hwmon(struct device *dev)
break;
}
data->fan_nominal_speed[i][state] = err;
+ /*
+ * Autodetect fan multiplier based on nominal rpm if multiplier
+ * was not specified as module param or in DMI. If fan reports
+ * rpm value too high then set multiplier to 1.
+ */
+ if (!fan_mult && err > I8K_FAN_RPM_THRESHOLD)
+ data->i8k_fan_mult = 1;
}
}
@@ -1270,15 +1373,12 @@ static int __init dell_smm_probe(struct platform_device *pdev)
struct dell_smm_data *data;
const struct dmi_system_id *id, *fan_control;
int ret;
- u8 fan;
data = devm_kzalloc(&pdev->dev, sizeof(struct dell_smm_data), GFP_KERNEL);
if (!data)
return -ENOMEM;
mutex_init(&data->i8k_mutex);
- data->i8k_fan_mult = I8K_FAN_MULT;
- data->i8k_fan_max = I8K_FAN_HIGH;
platform_set_drvdata(pdev, data);
if (dmi_check_system(i8k_blacklist_fan_support_dmi_table)) {
@@ -1313,7 +1413,9 @@ static int __init dell_smm_probe(struct platform_device *pdev)
fan_max = conf->fan_max;
}
- data->i8k_fan_max = fan_max ? : I8K_FAN_HIGH; /* Must not be 0 */
+ /* All options must not be 0 */
+ data->i8k_fan_mult = fan_mult ? : I8K_FAN_MULT;
+ data->i8k_fan_max = fan_max ? : I8K_FAN_HIGH;
data->i8k_pwm_mult = DIV_ROUND_UP(255, data->i8k_fan_max);
fan_control = dmi_first_match(i8k_whitelist_fan_control);
@@ -1325,25 +1427,6 @@ static int __init dell_smm_probe(struct platform_device *pdev)
dev_info(&pdev->dev, "enabling support for setting automatic/manual fan control\n");
}
- if (!fan_mult) {
- /*
- * Autodetect fan multiplier based on nominal rpm
- * If fan reports rpm value too high then set multiplier to 1
- */
- for (fan = 0; fan < DELL_SMM_NO_FANS; ++fan) {
- ret = i8k_get_fan_nominal_speed(data, fan, data->i8k_fan_max);
- if (ret < 0)
- continue;
-
- if (ret > I8K_FAN_MAX_RPM)
- data->i8k_fan_mult = 1;
- break;
- }
- } else {
- /* Fan multiplier was specified in module param or in dmi */
- data->i8k_fan_mult = fan_mult;
- }
-
ret = dell_smm_init_hwmon(&pdev->dev);
if (ret)
return ret;
generated by cgit (git 2.34.1) at 2025-06-07 03:32:48 +0000