| Message ID | 49a5c6db7eb5dd1c53d326e0f7314e8f9e258997.1511152748.git-series.andrew@aj.id.au (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
On Mon, Nov 20, 2017 at 03:12:06PM +1030, Andrew Jeffery wrote: > The dual tachometer feature is implemented in hardware with a TACHSEL > input to indicate the rotor under measurement, and exposed on the device > by extending the READ_FAN_SPEED_1 word with two extra bytes*. The need > to read the non-standard four-byte response leads to a cut-down > implementation of i2c_smbus_xfer_emulated() included in the driver. > Further, to expose the second rotor tachometer value to userspace the > values are exposed through virtual pages. We re-route accesses to > FAN_CONFIG_1_2 and READ_FAN_SPEED_1 on pages 23-28 (not defined by the > hardware) to the same registers on pages 0-5, and with the latter command > we extract the value from the second word of the four-byte response. > > * The documentation recommends the slower rotor be associated with > TACHSEL=0, which corresponds to the first word of the response. The > TACHSEL=0 measurement is used by the controller's closed-loop fan > management to judge target fan rate. > > Signed-off-by: Andrew Jeffery <andrew@aj.id.au> Applied. Thanks, Guenter > --- > Documentation/hwmon/max31785 | 8 +- > drivers/hwmon/pmbus/max31785.c | 147 ++++++++++++++++++++++++++++++++++- > 2 files changed, 152 insertions(+), 3 deletions(-) > > diff --git a/Documentation/hwmon/max31785 b/Documentation/hwmon/max31785 > index 7b0a0a8cdb6b..270c5f865261 100644 > --- a/Documentation/hwmon/max31785 > +++ b/Documentation/hwmon/max31785 > @@ -17,8 +17,9 @@ management with temperature and remote voltage sensing. Various fan control > features are provided, including PWM frequency control, temperature hysteresis, > dual tachometer measurements, and fan health monitoring. > > -For dual rotor fan configuration, the MAX31785 exposes the slowest rotor of the > -two in the fan[1-4]_input attributes. > +For dual-rotor configurations the MAX31785A exposes the second rotor tachometer > +readings in attributes fan[5-8]_input. By contrast the MAX31785 only exposes > +the slowest rotor measurement, and does so in the fan[1-4]_input attributes. > > Usage Notes > ----------- > @@ -31,7 +32,8 @@ Sysfs attributes > > fan[1-4]_alarm Fan alarm. > fan[1-4]_fault Fan fault. > -fan[1-4]_input Fan RPM. > +fan[1-8]_input Fan RPM. On the MAX31785A, inputs 5-8 correspond to the > + second rotor of fans 1-4 > fan[1-4]_target Fan input target > > in[1-6]_crit Critical maximum output voltage > diff --git a/drivers/hwmon/pmbus/max31785.c b/drivers/hwmon/pmbus/max31785.c > index 8706a696c89a..bffab449be39 100644 > --- a/drivers/hwmon/pmbus/max31785.c > +++ b/drivers/hwmon/pmbus/max31785.c > @@ -16,9 +16,79 @@ > > enum max31785_regs { > MFR_REVISION = 0x9b, > + MFR_FAN_CONFIG = 0xf1, > }; > > +#define MAX31785 0x3030 > +#define MAX31785A 0x3040 > + > +#define MFR_FAN_CONFIG_DUAL_TACH BIT(12) > + > #define MAX31785_NR_PAGES 23 > +#define MAX31785_NR_FAN_PAGES 6 > + > +static int max31785_read_byte_data(struct i2c_client *client, int page, > + int reg) > +{ > + if (page < MAX31785_NR_PAGES) > + return -ENODATA; > + > + switch (reg) { > + case PMBUS_VOUT_MODE: > + return -ENOTSUPP; > + case PMBUS_FAN_CONFIG_12: > + return pmbus_read_byte_data(client, page - MAX31785_NR_PAGES, > + reg); > + } > + > + return -ENODATA; > +} > + > +static int max31785_write_byte(struct i2c_client *client, int page, u8 value) > +{ > + if (page < MAX31785_NR_PAGES) > + return -ENODATA; > + > + return -ENOTSUPP; > +} > + > +static int max31785_read_long_data(struct i2c_client *client, int page, > + int reg, u32 *data) > +{ > + unsigned char cmdbuf[1]; > + unsigned char rspbuf[4]; > + int rc; > + > + struct i2c_msg msg[2] = { > + { > + .addr = client->addr, > + .flags = 0, > + .len = sizeof(cmdbuf), > + .buf = cmdbuf, > + }, > + { > + .addr = client->addr, > + .flags = I2C_M_RD, > + .len = sizeof(rspbuf), > + .buf = rspbuf, > + }, > + }; > + > + cmdbuf[0] = reg; > + > + rc = pmbus_set_page(client, page); > + if (rc < 0) > + return rc; > + > + rc = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg)); > + if (rc < 0) > + return rc; > + > + *data = (rspbuf[0] << (0 * 8)) | (rspbuf[1] << (1 * 8)) | > + (rspbuf[2] << (2 * 8)) | (rspbuf[3] << (3 * 8)); > + > + return rc; > +} > > static int max31785_get_pwm(struct i2c_client *client, int page) > { > @@ -62,9 +132,30 @@ static int max31785_get_pwm_mode(struct i2c_client *client, int page) > static int max31785_read_word_data(struct i2c_client *client, int page, > int reg) > { > + u32 val; > int rv; > > switch (reg) { > + case PMBUS_READ_FAN_SPEED_1: > + if (page < MAX31785_NR_PAGES) > + return -ENODATA; > + > + rv = max31785_read_long_data(client, page - MAX31785_NR_PAGES, > + reg, &val); > + if (rv < 0) > + return rv; > + > + rv = (val >> 16) & 0xffff; > + break; > + case PMBUS_FAN_COMMAND_1: > + /* > + * PMBUS_FAN_COMMAND_x is probed to judge whether or not to > + * expose fan control registers. > + * > + * Don't expose fan_target attribute for virtual pages. > + */ > + rv = (page >= MAX31785_NR_PAGES) ? -ENOTSUPP : -ENODATA; > + break; > case PMBUS_VIRT_PWM_1: > rv = max31785_get_pwm(client, page); > break; > @@ -157,11 +248,15 @@ static int max31785_write_word_data(struct i2c_client *client, int page, > #define MAX31785_VOUT_FUNCS \ > (PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT) > > +#define MAX37185_NUM_FAN_PAGES 6 > + > static const struct pmbus_driver_info max31785_info = { > .pages = MAX31785_NR_PAGES, > > .write_word_data = max31785_write_word_data, > + .read_byte_data = max31785_read_byte_data, > .read_word_data = max31785_read_word_data, > + .write_byte = max31785_write_byte, > > /* RPM */ > .format[PSC_FAN] = direct, > @@ -208,13 +303,46 @@ static const struct pmbus_driver_info max31785_info = { > .func[22] = MAX31785_VOUT_FUNCS, > }; > > +static int max31785_configure_dual_tach(struct i2c_client *client, > + struct pmbus_driver_info *info) > +{ > + int ret; > + int i; > + > + for (i = 0; i < MAX31785_NR_FAN_PAGES; i++) { > + ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, i); > + if (ret < 0) > + return ret; > + > + ret = i2c_smbus_read_word_data(client, MFR_FAN_CONFIG); > + if (ret < 0) > + return ret; > + > + if (ret & MFR_FAN_CONFIG_DUAL_TACH) { > + int virtual = MAX31785_NR_PAGES + i; > + > + info->pages = virtual + 1; > + info->func[virtual] |= PMBUS_HAVE_FAN12; > + info->func[virtual] |= PMBUS_PAGE_VIRTUAL; > + } > + } > + > + return 0; > +} > + > static int max31785_probe(struct i2c_client *client, > const struct i2c_device_id *id) > { > struct device *dev = &client->dev; > struct pmbus_driver_info *info; > + bool dual_tach = false; > s64 ret; > > + if (!i2c_check_functionality(client->adapter, > + I2C_FUNC_SMBUS_BYTE_DATA | > + I2C_FUNC_SMBUS_WORD_DATA)) > + return -ENODEV; > + > info = devm_kzalloc(dev, sizeof(struct pmbus_driver_info), GFP_KERNEL); > if (!info) > return -ENOMEM; > @@ -225,6 +353,25 @@ static int max31785_probe(struct i2c_client *client, > if (ret < 0) > return ret; > > + ret = i2c_smbus_read_word_data(client, MFR_REVISION); > + if (ret < 0) > + return ret; > + > + if (ret == MAX31785A) { > + dual_tach = true; > + } else if (ret == MAX31785) { > + if (!strcmp("max31785a", id->name)) > + dev_warn(dev, "Expected max3175a, found max31785: cannot provide secondary tachometer readings\n"); > + } else { > + return -ENODEV; > + } > + > + if (dual_tach) { > + ret = max31785_configure_dual_tach(client, info); > + if (ret < 0) > + return ret; > + } > + > return pmbus_do_probe(client, id, info); > } > -- 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 7b0a0a8cdb6b..270c5f865261 100644 --- a/Documentation/hwmon/max31785 +++ b/Documentation/hwmon/max31785 @@ -17,8 +17,9 @@ management with temperature and remote voltage sensing. Various fan control features are provided, including PWM frequency control, temperature hysteresis, dual tachometer measurements, and fan health monitoring. -For dual rotor fan configuration, the MAX31785 exposes the slowest rotor of the -two in the fan[1-4]_input attributes. +For dual-rotor configurations the MAX31785A exposes the second rotor tachometer +readings in attributes fan[5-8]_input. By contrast the MAX31785 only exposes +the slowest rotor measurement, and does so in the fan[1-4]_input attributes. Usage Notes ----------- @@ -31,7 +32,8 @@ Sysfs attributes fan[1-4]_alarm Fan alarm. fan[1-4]_fault Fan fault. -fan[1-4]_input Fan RPM. +fan[1-8]_input Fan RPM. On the MAX31785A, inputs 5-8 correspond to the + second rotor of fans 1-4 fan[1-4]_target Fan input target in[1-6]_crit Critical maximum output voltage diff --git a/drivers/hwmon/pmbus/max31785.c b/drivers/hwmon/pmbus/max31785.c index 8706a696c89a..bffab449be39 100644 --- a/drivers/hwmon/pmbus/max31785.c +++ b/drivers/hwmon/pmbus/max31785.c @@ -16,9 +16,79 @@ enum max31785_regs { MFR_REVISION = 0x9b, + MFR_FAN_CONFIG = 0xf1, }; +#define MAX31785 0x3030 +#define MAX31785A 0x3040 + +#define MFR_FAN_CONFIG_DUAL_TACH BIT(12) + #define MAX31785_NR_PAGES 23 +#define MAX31785_NR_FAN_PAGES 6 + +static int max31785_read_byte_data(struct i2c_client *client, int page, + int reg) +{ + if (page < MAX31785_NR_PAGES) + return -ENODATA; + + switch (reg) { + case PMBUS_VOUT_MODE: + return -ENOTSUPP; + case PMBUS_FAN_CONFIG_12: + return pmbus_read_byte_data(client, page - MAX31785_NR_PAGES, + reg); + } + + return -ENODATA; +} + +static int max31785_write_byte(struct i2c_client *client, int page, u8 value) +{ + if (page < MAX31785_NR_PAGES) + return -ENODATA; + + return -ENOTSUPP; +} + +static int max31785_read_long_data(struct i2c_client *client, int page, + int reg, u32 *data) +{ + unsigned char cmdbuf[1]; + unsigned char rspbuf[4]; + int rc; + + struct i2c_msg msg[2] = { + { + .addr = client->addr, + .flags = 0, + .len = sizeof(cmdbuf), + .buf = cmdbuf, + }, + { + .addr = client->addr, + .flags = I2C_M_RD, + .len = sizeof(rspbuf), + .buf = rspbuf, + }, + }; + + cmdbuf[0] = reg; + + rc = pmbus_set_page(client, page); + if (rc < 0) + return rc; + + rc = i2c_transfer(client->adapter, msg, ARRAY_SIZE(msg)); + if (rc < 0) + return rc; + + *data = (rspbuf[0] << (0 * 8)) | (rspbuf[1] << (1 * 8)) | + (rspbuf[2] << (2 * 8)) | (rspbuf[3] << (3 * 8)); + + return rc; +} static int max31785_get_pwm(struct i2c_client *client, int page) { @@ -62,9 +132,30 @@ static int max31785_get_pwm_mode(struct i2c_client *client, int page) static int max31785_read_word_data(struct i2c_client *client, int page, int reg) { + u32 val; int rv; switch (reg) { + case PMBUS_READ_FAN_SPEED_1: + if (page < MAX31785_NR_PAGES) + return -ENODATA; + + rv = max31785_read_long_data(client, page - MAX31785_NR_PAGES, + reg, &val); + if (rv < 0) + return rv; + + rv = (val >> 16) & 0xffff; + break; + case PMBUS_FAN_COMMAND_1: + /* + * PMBUS_FAN_COMMAND_x is probed to judge whether or not to + * expose fan control registers. + * + * Don't expose fan_target attribute for virtual pages. + */ + rv = (page >= MAX31785_NR_PAGES) ? -ENOTSUPP : -ENODATA; + break; case PMBUS_VIRT_PWM_1: rv = max31785_get_pwm(client, page); break; @@ -157,11 +248,15 @@ static int max31785_write_word_data(struct i2c_client *client, int page, #define MAX31785_VOUT_FUNCS \ (PMBUS_HAVE_VOUT | PMBUS_HAVE_STATUS_VOUT) +#define MAX37185_NUM_FAN_PAGES 6 + static const struct pmbus_driver_info max31785_info = { .pages = MAX31785_NR_PAGES, .write_word_data = max31785_write_word_data, + .read_byte_data = max31785_read_byte_data, .read_word_data = max31785_read_word_data, + .write_byte = max31785_write_byte, /* RPM */ .format[PSC_FAN] = direct, @@ -208,13 +303,46 @@ static const struct pmbus_driver_info max31785_info = { .func[22] = MAX31785_VOUT_FUNCS, }; +static int max31785_configure_dual_tach(struct i2c_client *client, + struct pmbus_driver_info *info) +{ + int ret; + int i; + + for (i = 0; i < MAX31785_NR_FAN_PAGES; i++) { + ret = i2c_smbus_write_byte_data(client, PMBUS_PAGE, i); + if (ret < 0) + return ret; + + ret = i2c_smbus_read_word_data(client, MFR_FAN_CONFIG); + if (ret < 0) + return ret; + + if (ret & MFR_FAN_CONFIG_DUAL_TACH) { + int virtual = MAX31785_NR_PAGES + i; + + info->pages = virtual + 1; + info->func[virtual] |= PMBUS_HAVE_FAN12; + info->func[virtual] |= PMBUS_PAGE_VIRTUAL; + } + } + + return 0; +} + static int max31785_probe(struct i2c_client *client, const struct i2c_device_id *id) { struct device *dev = &client->dev; struct pmbus_driver_info *info; + bool dual_tach = false; s64 ret; + if (!i2c_check_functionality(client->adapter, + I2C_FUNC_SMBUS_BYTE_DATA | + I2C_FUNC_SMBUS_WORD_DATA)) + return -ENODEV; + info = devm_kzalloc(dev, sizeof(struct pmbus_driver_info), GFP_KERNEL); if (!info) return -ENOMEM; @@ -225,6 +353,25 @@ static int max31785_probe(struct i2c_client *client, if (ret < 0) return ret; + ret = i2c_smbus_read_word_data(client, MFR_REVISION); + if (ret < 0) + return ret; + + if (ret == MAX31785A) { + dual_tach = true; + } else if (ret == MAX31785) { + if (!strcmp("max31785a", id->name)) + dev_warn(dev, "Expected max3175a, found max31785: cannot provide secondary tachometer readings\n"); + } else { + return -ENODEV; + } + + if (dual_tach) { + ret = max31785_configure_dual_tach(client, info); + if (ret < 0) + return ret; + } + return pmbus_do_probe(client, id, info); }
The dual tachometer feature is implemented in hardware with a TACHSEL input to indicate the rotor under measurement, and exposed on the device by extending the READ_FAN_SPEED_1 word with two extra bytes*. The need to read the non-standard four-byte response leads to a cut-down implementation of i2c_smbus_xfer_emulated() included in the driver. Further, to expose the second rotor tachometer value to userspace the values are exposed through virtual pages. We re-route accesses to FAN_CONFIG_1_2 and READ_FAN_SPEED_1 on pages 23-28 (not defined by the hardware) to the same registers on pages 0-5, and with the latter command we extract the value from the second word of the four-byte response. * The documentation recommends the slower rotor be associated with TACHSEL=0, which corresponds to the first word of the response. The TACHSEL=0 measurement is used by the controller's closed-loop fan management to judge target fan rate. Signed-off-by: Andrew Jeffery <andrew@aj.id.au> --- Documentation/hwmon/max31785 | 8 +- drivers/hwmon/pmbus/max31785.c | 147 ++++++++++++++++++++++++++++++++++- 2 files changed, 152 insertions(+), 3 deletions(-)