| Message ID | 20210322093904.2340-1-gismatov.az@mail.ru (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | lm63: Added thermal zone support | expand |
On 3/22/21 2:39 AM, Azat Gismatov wrote: > There are target systems where pwm controller is the lm63, but > temperature sensors aren't connected to the lm63 (sensors are > part of CPU and supported by own linux driver). Automatic fan > control by the lm63 chip doesn't work for that systems. > Thermal zone is much more convenient for embedded systems, than > fan-control, or any other userspace software, because It allow > to get smaller software footprint. Also with thermal zone we > can store all cooling settings in devicetree, which is easier > to maintain for embedded systems, than some userspace software. > Added support property "pwm-mode" (pwm-mode = "manual") for > devicetree to use a manual pwm mode in the lm63 driver. > > Cc: Jean Delvare <jdelvare@suse.com> > Cc: Guenter Roeck <linux@roeck-us.net> > Cc: Thierry Reding <thierry.reding@gmail.com> > Cc: Lee Jones <lee.jones@linaro.org> > Cc: linux-hwmon@vger.kernel.org > Signed-off-by: Azat Gismatov <gismatov.az@mail.ru> > --- > drivers/hwmon/lm63.c | 133 ++++++++++++++++++++++++++++++++++++++++++- > 1 file changed, 132 insertions(+), 1 deletion(-) > > diff --git a/drivers/hwmon/lm63.c b/drivers/hwmon/lm63.c > index 50f67265c71d..764bc528294f 100644 > --- a/drivers/hwmon/lm63.c > +++ b/drivers/hwmon/lm63.c > @@ -34,7 +34,9 @@ > #include <linux/err.h> > #include <linux/mutex.h> > #include <linux/of_device.h> > +#include <linux/pwm.h> > #include <linux/sysfs.h> > +#include <linux/thermal.h> > #include <linux/types.h> > > /* > @@ -97,6 +99,8 @@ static const unsigned short normal_i2c[] = { 0x18, 0x4c, 0x4e, I2C_CLIENT_END }; > #define LM63_MAX_CONVRATE_HZ 32 > #define LM96163_MAX_CONVRATE_HZ 26 > > +#define MAX_SENSORS 2 > + > /* > * Conversions and various macros > * For tachometer counts, the LM63 uses 16-bit values. > @@ -173,8 +177,15 @@ struct lm63_data { > bool lut_temp_highres; > bool remote_unsigned; /* true if unsigned remote upper limits */ > bool trutherm; > + struct pwm_chip chip; > + struct lm63_thermal_sensor thermal_sensor[MAX_SENSORS]; > }; > > +static inline struct lm63_data *to_pwm(struct pwm_chip *chip) > +{ > + return container_of(chip, struct lm63_data, chip); > +} > + > static inline int temp8_from_reg(struct lm63_data *data, int nr) > { > if (data->remote_unsigned) > @@ -1015,9 +1026,15 @@ static void lm63_init_client(struct lm63_data *data) > { > struct i2c_client *client = data->client; > struct device *dev = &client->dev; > + const char *pwm_mode; > u8 convrate; > > data->config = i2c_smbus_read_byte_data(client, LM63_REG_CONFIG1); > + pwm_mode = of_get_property(dev->of_node, "pwm-mode", NULL); > + if (pwm_mode) { > + if (!strcmp(pwm_mode, "manual")) > + i2c_smbus_write_byte_data(client, LM63_REG_CONFIG_FAN, 0x20); > + } This would require dt maintainer approval. I would, however argue that it is not needed: If the chip registers as thermal cooling device and has associated devicetree nodes, it should be locked to manual mode, and manipulating chip configuration using sysfs attributes should be disabled. > data->config_fan = i2c_smbus_read_byte_data(client, > LM63_REG_CONFIG_FAN); > > @@ -1087,6 +1104,108 @@ static void lm63_init_client(struct lm63_data *data) > (data->config_fan & 0x20) ? "manual" : "auto"); > } > > +static int lm63_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, > + const struct pwm_state *state) > +{ > + struct lm63_data *data = to_pwm(chip); > + struct i2c_client *client = data->client; > + int ret = -EINVAL; > + u8 pwm_mode; > + u8 val; > + > + mutex_lock(&data->update_lock); > + pwm_mode = i2c_smbus_read_byte_data(client, LM63_REG_CONFIG_FAN); > + if (!(pwm_mode >> 5)) { > + mutex_unlock(&data->update_lock); > + return -EPERM; > + } > + > + if (state->period > 1) { > + val = state->duty_cycle * 255 / (state->period - 1); > + val = clamp_val(val, 0, 255); > + val = data->pwm_highres ? val : > + (val * data->pwm1_freq * 2 + 127) / 255; > + ret = i2c_smbus_write_byte_data(client, LM63_REG_PWM_VALUE, val); > + } > + > + mutex_unlock(&data->update_lock); > + return ret; > +} > + > +static const struct pwm_ops lm63_pwm_ops = { > + .apply = lm63_pwm_apply, > + .owner = THIS_MODULE, > +}; > + > +static void lm63_pwm_remove(void *arg) > +{ > + struct i2c_client *client = arg; > + struct lm63_data *data = i2c_get_clientdata(client); > + > + pwmchip_remove(&data->chip); > +} > + > +static int lm63_init_pwm(struct lm63_data *data) > +{ > + struct i2c_client *client = data->client; > + int ret; > + > + ret = devm_add_action(&client->dev, lm63_pwm_remove, client); > + if (ret) > + return ret; > + This must be done after calling pwmchip_add(). > + /* Initialize chip */ > + > + data->chip.dev = &client->dev; > + data->chip.ops = &lm63_pwm_ops; > + data->chip.base = -1; > + data->chip.npwm = 1; > + > + ret = pwmchip_add(&data->chip); > + if (ret < 0) { > + dev_warn(&client->dev, "pwmchip_add() failed: %d\n", ret); > + return ret; > + } > + > + return 0; > +} > + > +static int lm63_get_temp(void *data, int *temp) > +{ > + struct lm63_thermal_sensor *thermal_sensor = data; > + > + mutex_lock(&thermal_sensor->data->update_lock); > + *temp = i2c_smbus_read_byte_data(thermal_sensor->data->client, > + LM63_REG_LOCAL_TEMP + thermal_sensor->sensor_id) * 1000; > + mutex_unlock(&thermal_sensor->data->update_lock); I don't immediately see the need for this lock. > + > + return 0; > +} > + > +static const struct thermal_zone_of_device_ops lm63_tz_ops = { > + .get_temp = lm63_get_temp, > +}; > + > +static void lm63_init_thermal(struct lm63_data *data) > +{ > + struct i2c_client *client = data->client; > + struct lm63_thermal_sensor *thermal_sensor; > + unsigned int i; > + > + thermal_sensor = data->thermal_sensor; > + for (i = 0; i < MAX_SENSORS; i++, thermal_sensor++) { > + thermal_sensor->data = data; > + thermal_sensor->sensor_id = i; > + thermal_sensor->tz = devm_thermal_zone_of_sensor_register(&client->dev, > + i, thermal_sensor, &lm63_tz_ops); > + As far as I can see this will happen if there is no thermal zone configuration in the system, meaning almost all the time. The warning message below is therefore unacceptable. A return value of -ENODEV must be silently ignored. Also, this change does not match the commit description. The argument made there was that the LM63 is the pwm controller, but that the chip temperature sensor is not used to make thermal decisions. If the chip temperature sensor is not used to make thermal decisions, it does not have to be registered as thermal zone. The argument made in the description should probably be that the temperature sensor in the lm63 is not the only temperature sensor in the system used to make thermal decisions. That is, however, not currently the case. Please make sure that the description matches the code. > + if (IS_ERR(thermal_sensor->tz)) { > + dev_warn(&client->dev, "unable to register thermal sensor %ld\n", > + PTR_ERR(thermal_sensor->tz)); > + } > + } > +} > + > static const struct i2c_device_id lm63_id[]; > > static int lm63_probe(struct i2c_client *client) > @@ -1095,6 +1214,7 @@ static int lm63_probe(struct i2c_client *client) > struct device *hwmon_dev; > struct lm63_data *data; > int groups = 0; > + int ret; > > data = devm_kzalloc(dev, sizeof(struct lm63_data), GFP_KERNEL); > if (!data) > @@ -1126,7 +1246,18 @@ static int lm63_probe(struct i2c_client *client) > > hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, > data, data->groups); > - return PTR_ERR_OR_ZERO(hwmon_dev); > + if (IS_ERR(hwmon_dev)) > + return PTR_ERR(hwmon_dev); > + > + i2c_set_clientdata(client, data); > + lm63_init_thermal(data); > + if (IS_ENABLED(CONFIG_PWM)) { > + ret = lm63_init_pwm(data); > + if (ret) > + lm63_pwm_remove(data); This is not needed if devm_add_action_or_reset() is called in lm63_init_pwm() after successful pwm chip registration. Also, other hwmon drivers drivers register as thermal cooling device. You'll have to explain why this is better (and how it ties into the thermal subsystem), and why the dependency on the pwm subsystem is needed for this cooling device to work. Thanks, Guenter
diff --git a/drivers/hwmon/lm63.c b/drivers/hwmon/lm63.c index 50f67265c71d..764bc528294f 100644 --- a/drivers/hwmon/lm63.c +++ b/drivers/hwmon/lm63.c @@ -34,7 +34,9 @@ #include <linux/err.h> #include <linux/mutex.h> #include <linux/of_device.h> +#include <linux/pwm.h> #include <linux/sysfs.h> +#include <linux/thermal.h> #include <linux/types.h> /* @@ -97,6 +99,8 @@ static const unsigned short normal_i2c[] = { 0x18, 0x4c, 0x4e, I2C_CLIENT_END }; #define LM63_MAX_CONVRATE_HZ 32 #define LM96163_MAX_CONVRATE_HZ 26 +#define MAX_SENSORS 2 + /* * Conversions and various macros * For tachometer counts, the LM63 uses 16-bit values. @@ -173,8 +177,15 @@ struct lm63_data { bool lut_temp_highres; bool remote_unsigned; /* true if unsigned remote upper limits */ bool trutherm; + struct pwm_chip chip; + struct lm63_thermal_sensor thermal_sensor[MAX_SENSORS]; }; +static inline struct lm63_data *to_pwm(struct pwm_chip *chip) +{ + return container_of(chip, struct lm63_data, chip); +} + static inline int temp8_from_reg(struct lm63_data *data, int nr) { if (data->remote_unsigned) @@ -1015,9 +1026,15 @@ static void lm63_init_client(struct lm63_data *data) { struct i2c_client *client = data->client; struct device *dev = &client->dev; + const char *pwm_mode; u8 convrate; data->config = i2c_smbus_read_byte_data(client, LM63_REG_CONFIG1); + pwm_mode = of_get_property(dev->of_node, "pwm-mode", NULL); + if (pwm_mode) { + if (!strcmp(pwm_mode, "manual")) + i2c_smbus_write_byte_data(client, LM63_REG_CONFIG_FAN, 0x20); + } data->config_fan = i2c_smbus_read_byte_data(client, LM63_REG_CONFIG_FAN); @@ -1087,6 +1104,108 @@ static void lm63_init_client(struct lm63_data *data) (data->config_fan & 0x20) ? "manual" : "auto"); } +static int lm63_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct lm63_data *data = to_pwm(chip); + struct i2c_client *client = data->client; + int ret = -EINVAL; + u8 pwm_mode; + u8 val; + + mutex_lock(&data->update_lock); + pwm_mode = i2c_smbus_read_byte_data(client, LM63_REG_CONFIG_FAN); + if (!(pwm_mode >> 5)) { + mutex_unlock(&data->update_lock); + return -EPERM; + } + + if (state->period > 1) { + val = state->duty_cycle * 255 / (state->period - 1); + val = clamp_val(val, 0, 255); + val = data->pwm_highres ? val : + (val * data->pwm1_freq * 2 + 127) / 255; + ret = i2c_smbus_write_byte_data(client, LM63_REG_PWM_VALUE, val); + } + + mutex_unlock(&data->update_lock); + return ret; +} + +static const struct pwm_ops lm63_pwm_ops = { + .apply = lm63_pwm_apply, + .owner = THIS_MODULE, +}; + +static void lm63_pwm_remove(void *arg) +{ + struct i2c_client *client = arg; + struct lm63_data *data = i2c_get_clientdata(client); + + pwmchip_remove(&data->chip); +} + +static int lm63_init_pwm(struct lm63_data *data) +{ + struct i2c_client *client = data->client; + int ret; + + ret = devm_add_action(&client->dev, lm63_pwm_remove, client); + if (ret) + return ret; + + /* Initialize chip */ + + data->chip.dev = &client->dev; + data->chip.ops = &lm63_pwm_ops; + data->chip.base = -1; + data->chip.npwm = 1; + + ret = pwmchip_add(&data->chip); + if (ret < 0) { + dev_warn(&client->dev, "pwmchip_add() failed: %d\n", ret); + return ret; + } + + return 0; +} + +static int lm63_get_temp(void *data, int *temp) +{ + struct lm63_thermal_sensor *thermal_sensor = data; + + mutex_lock(&thermal_sensor->data->update_lock); + *temp = i2c_smbus_read_byte_data(thermal_sensor->data->client, + LM63_REG_LOCAL_TEMP + thermal_sensor->sensor_id) * 1000; + mutex_unlock(&thermal_sensor->data->update_lock); + + return 0; +} + +static const struct thermal_zone_of_device_ops lm63_tz_ops = { + .get_temp = lm63_get_temp, +}; + +static void lm63_init_thermal(struct lm63_data *data) +{ + struct i2c_client *client = data->client; + struct lm63_thermal_sensor *thermal_sensor; + unsigned int i; + + thermal_sensor = data->thermal_sensor; + for (i = 0; i < MAX_SENSORS; i++, thermal_sensor++) { + thermal_sensor->data = data; + thermal_sensor->sensor_id = i; + thermal_sensor->tz = devm_thermal_zone_of_sensor_register(&client->dev, + i, thermal_sensor, &lm63_tz_ops); + + if (IS_ERR(thermal_sensor->tz)) { + dev_warn(&client->dev, "unable to register thermal sensor %ld\n", + PTR_ERR(thermal_sensor->tz)); + } + } +} + static const struct i2c_device_id lm63_id[]; static int lm63_probe(struct i2c_client *client) @@ -1095,6 +1214,7 @@ static int lm63_probe(struct i2c_client *client) struct device *hwmon_dev; struct lm63_data *data; int groups = 0; + int ret; data = devm_kzalloc(dev, sizeof(struct lm63_data), GFP_KERNEL); if (!data) @@ -1126,7 +1246,18 @@ static int lm63_probe(struct i2c_client *client) hwmon_dev = devm_hwmon_device_register_with_groups(dev, client->name, data, data->groups); - return PTR_ERR_OR_ZERO(hwmon_dev); + if (IS_ERR(hwmon_dev)) + return PTR_ERR(hwmon_dev); + + i2c_set_clientdata(client, data); + lm63_init_thermal(data); + if (IS_ENABLED(CONFIG_PWM)) { + ret = lm63_init_pwm(data); + if (ret) + lm63_pwm_remove(data); + } + + return 0; } /*
There are target systems where pwm controller is the lm63, but temperature sensors aren't connected to the lm63 (sensors are part of CPU and supported by own linux driver). Automatic fan control by the lm63 chip doesn't work for that systems. Thermal zone is much more convenient for embedded systems, than fan-control, or any other userspace software, because It allow to get smaller software footprint. Also with thermal zone we can store all cooling settings in devicetree, which is easier to maintain for embedded systems, than some userspace software. Added support property "pwm-mode" (pwm-mode = "manual") for devicetree to use a manual pwm mode in the lm63 driver. Cc: Jean Delvare <jdelvare@suse.com> Cc: Guenter Roeck <linux@roeck-us.net> Cc: Thierry Reding <thierry.reding@gmail.com> Cc: Lee Jones <lee.jones@linaro.org> Cc: linux-hwmon@vger.kernel.org Signed-off-by: Azat Gismatov <gismatov.az@mail.ru> --- drivers/hwmon/lm63.c | 133 ++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 132 insertions(+), 1 deletion(-)