| Message ID | 8c06a1a1fcb67745fb9015b5c3f69f6f12ae0b0f.1511152748.git-series.andrew@aj.id.au (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Mon, Nov 20, 2017 at 03:12:04PM +1030, Andrew Jeffery wrote: > The implementation makes use of the new fan control virtual registers > exposed by the pmbus core. It mixes use of the default implementations > with some overrides via the read/write handlers to handle FAN_COMMAND_1 > on the MAX31785, whose definition breaks the value range into various > control bands dependent on RPM or PWM mode. > > Signed-off-by: Andrew Jeffery <andrew@aj.id.au> Applied. Thanks, Guenter > --- > Documentation/hwmon/max31785 | 7 ++- > drivers/hwmon/pmbus/max31785.c | 138 +++++++++++++++++++++++++++++++++- > 2 files changed, 144 insertions(+), 1 deletion(-) > > diff --git a/Documentation/hwmon/max31785 b/Documentation/hwmon/max31785 > index 45fb6093dec2..7b0a0a8cdb6b 100644 > --- a/Documentation/hwmon/max31785 > +++ b/Documentation/hwmon/max31785 > @@ -32,6 +32,7 @@ Sysfs attributes > fan[1-4]_alarm Fan alarm. > fan[1-4]_fault Fan fault. > fan[1-4]_input Fan RPM. > +fan[1-4]_target Fan input target > > in[1-6]_crit Critical maximum output voltage > in[1-6]_crit_alarm Output voltage critical high alarm > @@ -44,6 +45,12 @@ in[1-6]_max_alarm Output voltage high alarm > in[1-6]_min Minimum output voltage > in[1-6]_min_alarm Output voltage low alarm > > +pwm[1-4] Fan target duty cycle (0..255) > +pwm[1-4]_enable 0: Full-speed > + 1: Manual PWM control > + 2: Automatic PWM (tach-feedback RPM fan-control) > + 3: Automatic closed-loop (temp-feedback fan-control) > + > temp[1-11]_crit Critical high temperature > temp[1-11]_crit_alarm Chip temperature critical high alarm > temp[1-11]_input Measured temperature > diff --git a/drivers/hwmon/pmbus/max31785.c b/drivers/hwmon/pmbus/max31785.c > index 9313849d5160..8706a696c89a 100644 > --- a/drivers/hwmon/pmbus/max31785.c > +++ b/drivers/hwmon/pmbus/max31785.c > @@ -20,8 +20,136 @@ enum max31785_regs { > > #define MAX31785_NR_PAGES 23 > > +static int max31785_get_pwm(struct i2c_client *client, int page) > +{ > + int rv; > + > + rv = pmbus_get_fan_rate_device(client, page, 0, percent); > + if (rv < 0) > + return rv; > + else if (rv >= 0x8000) > + return 0; > + else if (rv >= 0x2711) > + return 0x2710; > + > + return rv; > +} > + > +static int max31785_get_pwm_mode(struct i2c_client *client, int page) > +{ > + int config; > + int command; > + > + config = pmbus_read_byte_data(client, page, PMBUS_FAN_CONFIG_12); > + if (config < 0) > + return config; > + > + command = pmbus_read_word_data(client, page, PMBUS_FAN_COMMAND_1); > + if (command < 0) > + return command; > + > + if (config & PB_FAN_1_RPM) > + return (command >= 0x8000) ? 3 : 2; > + > + if (command >= 0x8000) > + return 3; > + else if (command >= 0x2711) > + return 0; > + > + return 1; > +} > + > +static int max31785_read_word_data(struct i2c_client *client, int page, > + int reg) > +{ > + int rv; > + > + switch (reg) { > + case PMBUS_VIRT_PWM_1: > + rv = max31785_get_pwm(client, page); > + break; > + case PMBUS_VIRT_PWM_ENABLE_1: > + rv = max31785_get_pwm_mode(client, page); > + break; > + default: > + rv = -ENODATA; > + break; > + } > + > + return rv; > +} > + > +static inline u32 max31785_scale_pwm(u32 sensor_val) > +{ > + /* > + * The datasheet describes the accepted value range for manual PWM as > + * [0, 0x2710], while the hwmon pwmX sysfs interface accepts values in > + * [0, 255]. The MAX31785 uses DIRECT mode to scale the FAN_COMMAND > + * registers and in PWM mode the coefficients are m=1, b=0, R=2. The > + * important observation here is that 0x2710 == 10000 == 100 * 100. > + * > + * R=2 (== 10^2 == 100) accounts for scaling the value provided at the > + * sysfs interface into the required hardware resolution, but it does > + * not yet yield a value that we can write to the device (this initial > + * scaling is handled by pmbus_data2reg()). Multiplying by 100 below > + * translates the parameter value into the percentage units required by > + * PMBus, and then we scale back by 255 as required by the hwmon pwmX > + * interface to yield the percentage value at the appropriate > + * resolution for hardware. > + */ > + return (sensor_val * 100) / 255; > +} > + > +static int max31785_pwm_enable(struct i2c_client *client, int page, > + u16 word) > +{ > + int config = 0; > + int rate; > + > + switch (word) { > + case 0: > + rate = 0x7fff; > + break; > + case 1: > + rate = pmbus_get_fan_rate_cached(client, page, 0, percent); > + if (rate < 0) > + return rate; > + rate = max31785_scale_pwm(rate); > + break; > + case 2: > + config = PB_FAN_1_RPM; > + rate = pmbus_get_fan_rate_cached(client, page, 0, rpm); > + if (rate < 0) > + return rate; > + break; > + case 3: > + rate = 0xffff; > + break; > + default: > + return -EINVAL; > + } > + > + return pmbus_update_fan(client, page, 0, config, PB_FAN_1_RPM, rate); > +} > + > +static int max31785_write_word_data(struct i2c_client *client, int page, > + int reg, u16 word) > +{ > + switch (reg) { > + case PMBUS_VIRT_PWM_1: > + return pmbus_update_fan(client, page, 0, 0, PB_FAN_1_RPM, > + max31785_scale_pwm(word)); > + case PMBUS_VIRT_PWM_ENABLE_1: > + return max31785_pwm_enable(client, page, word); > + default: > + break; > + } > + > + return -ENODATA; > +} > + > #define MAX31785_FAN_FUNCS \ > - (PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12) > + (PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12 | PMBUS_HAVE_PWM12) > > #define MAX31785_TEMP_FUNCS \ > (PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP) > @@ -32,11 +160,19 @@ enum max31785_regs { > static const struct pmbus_driver_info max31785_info = { > .pages = MAX31785_NR_PAGES, > > + .write_word_data = max31785_write_word_data, > + .read_word_data = max31785_read_word_data, > + > /* RPM */ > .format[PSC_FAN] = direct, > .m[PSC_FAN] = 1, > .b[PSC_FAN] = 0, > .R[PSC_FAN] = 0, > + /* PWM */ > + .format[PSC_PWM] = direct, > + .m[PSC_PWM] = 1, > + .b[PSC_PWM] = 0, > + .R[PSC_PWM] = 2, > .func[0] = MAX31785_FAN_FUNCS, > .func[1] = MAX31785_FAN_FUNCS, > .func[2] = MAX31785_FAN_FUNCS, -- To unsubscribe from this list: send the line "unsubscribe linux-hwmon" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/Documentation/hwmon/max31785 b/Documentation/hwmon/max31785 index 45fb6093dec2..7b0a0a8cdb6b 100644 --- a/Documentation/hwmon/max31785 +++ b/Documentation/hwmon/max31785 @@ -32,6 +32,7 @@ Sysfs attributes fan[1-4]_alarm Fan alarm. fan[1-4]_fault Fan fault. fan[1-4]_input Fan RPM. +fan[1-4]_target Fan input target in[1-6]_crit Critical maximum output voltage in[1-6]_crit_alarm Output voltage critical high alarm @@ -44,6 +45,12 @@ in[1-6]_max_alarm Output voltage high alarm in[1-6]_min Minimum output voltage in[1-6]_min_alarm Output voltage low alarm +pwm[1-4] Fan target duty cycle (0..255) +pwm[1-4]_enable 0: Full-speed + 1: Manual PWM control + 2: Automatic PWM (tach-feedback RPM fan-control) + 3: Automatic closed-loop (temp-feedback fan-control) + temp[1-11]_crit Critical high temperature temp[1-11]_crit_alarm Chip temperature critical high alarm temp[1-11]_input Measured temperature diff --git a/drivers/hwmon/pmbus/max31785.c b/drivers/hwmon/pmbus/max31785.c index 9313849d5160..8706a696c89a 100644 --- a/drivers/hwmon/pmbus/max31785.c +++ b/drivers/hwmon/pmbus/max31785.c @@ -20,8 +20,136 @@ enum max31785_regs { #define MAX31785_NR_PAGES 23 +static int max31785_get_pwm(struct i2c_client *client, int page) +{ + int rv; + + rv = pmbus_get_fan_rate_device(client, page, 0, percent); + if (rv < 0) + return rv; + else if (rv >= 0x8000) + return 0; + else if (rv >= 0x2711) + return 0x2710; + + return rv; +} + +static int max31785_get_pwm_mode(struct i2c_client *client, int page) +{ + int config; + int command; + + config = pmbus_read_byte_data(client, page, PMBUS_FAN_CONFIG_12); + if (config < 0) + return config; + + command = pmbus_read_word_data(client, page, PMBUS_FAN_COMMAND_1); + if (command < 0) + return command; + + if (config & PB_FAN_1_RPM) + return (command >= 0x8000) ? 3 : 2; + + if (command >= 0x8000) + return 3; + else if (command >= 0x2711) + return 0; + + return 1; +} + +static int max31785_read_word_data(struct i2c_client *client, int page, + int reg) +{ + int rv; + + switch (reg) { + case PMBUS_VIRT_PWM_1: + rv = max31785_get_pwm(client, page); + break; + case PMBUS_VIRT_PWM_ENABLE_1: + rv = max31785_get_pwm_mode(client, page); + break; + default: + rv = -ENODATA; + break; + } + + return rv; +} + +static inline u32 max31785_scale_pwm(u32 sensor_val) +{ + /* + * The datasheet describes the accepted value range for manual PWM as + * [0, 0x2710], while the hwmon pwmX sysfs interface accepts values in + * [0, 255]. The MAX31785 uses DIRECT mode to scale the FAN_COMMAND + * registers and in PWM mode the coefficients are m=1, b=0, R=2. The + * important observation here is that 0x2710 == 10000 == 100 * 100. + * + * R=2 (== 10^2 == 100) accounts for scaling the value provided at the + * sysfs interface into the required hardware resolution, but it does + * not yet yield a value that we can write to the device (this initial + * scaling is handled by pmbus_data2reg()). Multiplying by 100 below + * translates the parameter value into the percentage units required by + * PMBus, and then we scale back by 255 as required by the hwmon pwmX + * interface to yield the percentage value at the appropriate + * resolution for hardware. + */ + return (sensor_val * 100) / 255; +} + +static int max31785_pwm_enable(struct i2c_client *client, int page, + u16 word) +{ + int config = 0; + int rate; + + switch (word) { + case 0: + rate = 0x7fff; + break; + case 1: + rate = pmbus_get_fan_rate_cached(client, page, 0, percent); + if (rate < 0) + return rate; + rate = max31785_scale_pwm(rate); + break; + case 2: + config = PB_FAN_1_RPM; + rate = pmbus_get_fan_rate_cached(client, page, 0, rpm); + if (rate < 0) + return rate; + break; + case 3: + rate = 0xffff; + break; + default: + return -EINVAL; + } + + return pmbus_update_fan(client, page, 0, config, PB_FAN_1_RPM, rate); +} + +static int max31785_write_word_data(struct i2c_client *client, int page, + int reg, u16 word) +{ + switch (reg) { + case PMBUS_VIRT_PWM_1: + return pmbus_update_fan(client, page, 0, 0, PB_FAN_1_RPM, + max31785_scale_pwm(word)); + case PMBUS_VIRT_PWM_ENABLE_1: + return max31785_pwm_enable(client, page, word); + default: + break; + } + + return -ENODATA; +} + #define MAX31785_FAN_FUNCS \ - (PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12) + (PMBUS_HAVE_FAN12 | PMBUS_HAVE_STATUS_FAN12 | PMBUS_HAVE_PWM12) #define MAX31785_TEMP_FUNCS \ (PMBUS_HAVE_TEMP | PMBUS_HAVE_STATUS_TEMP) @@ -32,11 +160,19 @@ enum max31785_regs { static const struct pmbus_driver_info max31785_info = { .pages = MAX31785_NR_PAGES, + .write_word_data = max31785_write_word_data, + .read_word_data = max31785_read_word_data, + /* RPM */ .format[PSC_FAN] = direct, .m[PSC_FAN] = 1, .b[PSC_FAN] = 0, .R[PSC_FAN] = 0, + /* PWM */ + .format[PSC_PWM] = direct, + .m[PSC_PWM] = 1, + .b[PSC_PWM] = 0, + .R[PSC_PWM] = 2, .func[0] = MAX31785_FAN_FUNCS, .func[1] = MAX31785_FAN_FUNCS, .func[2] = MAX31785_FAN_FUNCS,
The implementation makes use of the new fan control virtual registers exposed by the pmbus core. It mixes use of the default implementations with some overrides via the read/write handlers to handle FAN_COMMAND_1 on the MAX31785, whose definition breaks the value range into various control bands dependent on RPM or PWM mode. Signed-off-by: Andrew Jeffery <andrew@aj.id.au> --- Documentation/hwmon/max31785 | 7 ++- drivers/hwmon/pmbus/max31785.c | 138 +++++++++++++++++++++++++++++++++- 2 files changed, 144 insertions(+), 1 deletion(-)