| Message ID | 20230913152135.457892-1-daniel.matyas@analog.com |
|---|---|
| Headers | show |
| Series | Why no v2? | expand |
On 9/13/23 08:21, Daniel Matyas wrote: > This is kind of v2, but not exactly. Major changes were applied and > commits were separated. The latter is the main reason why I did not call > this v2. > That is neither a reason nor a valid argument. Just call it v2 and mark the added patch(es) with a changelog along the line of "v2: Added patch". And a subject of "Why no v2?" is really useless and pointless. Guenter
On 9/13/23 08:21, Daniel Matyas wrote: > Used fwnode to retrieve data from the devicetree in the init_client > function. > > Added support for devices max31828 and max31829. For these devices, when > adi,flt-q and/or adi,alrm-pol are not mentioned, the default > configuration is loaded. > Still more than one logical change in a single patch. > Signed-off-by: Daniel Matyas <daniel.matyas@analog.com> > --- > Documentation/hwmon/max31827.rst | 47 ++++++++-- > drivers/hwmon/max31827.c | 142 +++++++++++++++++++++++++++---- > 2 files changed, 165 insertions(+), 24 deletions(-) > > diff --git a/Documentation/hwmon/max31827.rst b/Documentation/hwmon/max31827.rst > index 9a1055a007cf..e0eca1eb5c06 100644 > --- a/Documentation/hwmon/max31827.rst > +++ b/Documentation/hwmon/max31827.rst > @@ -52,13 +52,21 @@ MAX31827 has low and over temperature alarms with an effective value and a > hysteresis value: -40 and -30 degrees for under temperature alarm and +100 and > +90 degrees for over temperature alarm. > > -The alarm can be configured in comparator and interrupt mode. Currently only > -comparator mode is implemented. In Comparator mode, the OT/UT status bits have a > -value of 1 when the temperature rises above the TH value or falls below TL, > -which is also subject to the Fault Queue selection. OT status returns to 0 when > -the temperature drops below the TH_HYST value or when shutdown mode is entered. > -Similarly, UT status returns to 0 when the temperature rises above TL_HYST value > -or when shutdown mode is entered. > +The alarm can be configured in comparator and interrupt mode from the > +devicetree. In Comparator mode, the OT/UT status bits have a value of 1 when the > +temperature rises above the TH value or falls below TL, which is also subject to > +the Fault Queue selection. OT status returns to 0 when the temperature drops > +below the TH_HYST value or when shutdown mode is entered. Similarly, UT status > +returns to 0 when the temperature rises above TL_HYST value or when shutdown > +mode is entered. > + > +In interrupt mode exceeding TH also sets OT status to 1, which remains set until > +a read operation is performed on the configuration/status register (max or min > +attribute); at this point, it returns to 0. Once OT status is set to 1 from > +exceeding TH and reset, it is set to 1 again only when the temperature drops > +below TH_HYST. The output remains asserted until it is reset by a read. It is > +set again if the temperature rises above TH, and so on. The same logic applies > +to the operation of the UT status bit. > > Putting the MAX31827 into shutdown mode also resets the OT/UT status bits. Note > that if the mode is changed while OT/UT status bits are set, an OT/UT status > @@ -68,6 +76,17 @@ clear the status bits before changing the operating mode. > > The conversions can be manual with the one-shot functionality and automatic with > a set frequency. When powered on, the chip measures temperatures with 1 conv/s. > +The conversion rate can be modified with update_interval attribute of the chip. > +Conversion/second = 1/update_interval. Thus, the available options according to > +the data sheet are: > + - 64000 (ms) = 1 conv/64 sec > + - 32000 (ms) = 1 conv/32 sec > + - 16000 (ms) = 1 conv/16 sec > + - 4000 (ms) = 1 conv/4 sec > + - 1000 (ms) = 1 conv/sec (default) > + - 250 (ms) = 4 conv/sec > + - 125 (ms) = 8 conv/sec > + > Enabling the device when it is already enabled has the side effect of setting > the conversion frequency to 1 conv/s. The conversion time varies depending on > the resolution. The conversion time doubles with every bit of increased > @@ -83,8 +102,18 @@ in the writing of alarm values too. For positive numbers the user-input value > will always be rounded down to the nearest possible value, for negative numbers > the user-input will always be rounded up to the nearest possible value. > > +Bus timeout resets the I2C-compatible interface when SCL is low for more than > +30ms (nominal). > + > +Alarm polarity determines if the active state of the alarm is low or high. The > +behavior for both settings is dependent on the Fault Queue setting. The ALARM > +pin is an open-drain output and requires a pullup resistor to operate. > + > +The Fault Queue bits select how many consecutive temperature faults must occur > +before overtemperature or undertemperature faults are indicated in the > +corresponding status bits. > + > Notes > ----- > > -Currently fault queue, alarm polarity and resolution cannot be modified. > -PEC is not implemented either. > +PEC and resolution are not implemented. > diff --git a/drivers/hwmon/max31827.c b/drivers/hwmon/max31827.c > index f05762219995..4dc14642775a 100644 > --- a/drivers/hwmon/max31827.c > +++ b/drivers/hwmon/max31827.c > @@ -12,6 +12,19 @@ > #include <linux/i2c.h> > #include <linux/mutex.h> > #include <linux/regmap.h> > +#include <linux/hwmon-sysfs.h> > +#include <linux/of_device.h> > + > +/* > + * gcc turns __builtin_ffsll() into a call to __ffsdi2(), which is not provided > + * by every architecture. __ffs64() is available on all architectures, but the > + * result is not defined if no bits are set. > + */ > +#define max31827__bf_shf(x) \ > + ({ \ > + typeof(x) x_ = (x); \ > + ((x_) != 0) ? __ffs64(x_) : 0x0; \ > + }) > > #define MAX31827_T_REG 0x0 > #define MAX31827_CONFIGURATION_REG 0x2 > @@ -22,15 +35,25 @@ > > #define MAX31827_CONFIGURATION_1SHOT_MASK BIT(0) > #define MAX31827_CONFIGURATION_CNV_RATE_MASK GENMASK(3, 1) > -#define MAX31827_CONFIGURATION_U_TEMP_STAT_MASK BIT(14) > -#define MAX31827_CONFIGURATION_O_TEMP_STAT_MASK BIT(15) > +#define MAX31827_CONFIGURATION_TIMEOUT_MASK BIT(5) > +#define MAX31827_CONFIGURATION_RESOLUTION_MASK GENMASK(7, 6) > +#define MAX31827_CONFIGURATION_ALRM_POL_MASK BIT(8) > +#define MAX31827_CONFIGURATION_COMP_INT_MASK BIT(9) > +#define MAX31827_CONFIGURATION_FLT_Q_MASK GENMASK(11, 10) > +#define MAX31827_CONFIGURATION_U_TEMP_STAT_MASK BIT(14) > +#define MAX31827_CONFIGURATION_O_TEMP_STAT_MASK BIT(15) > > #define MAX31827_12_BIT_CNV_TIME 140 > > +#define MAX31827_FLT_Q_1 0x0 > +#define MAX31827_FLT_Q_4 0x2 > + > #define MAX31827_16_BIT_TO_M_DGR(x) (sign_extend32(x, 15) * 1000 / 16) > #define MAX31827_M_DGR_TO_16_BIT(x) (((x) << 4) / 1000) > #define MAX31827_DEVICE_ENABLE(x) ((x) ? 0xA : 0x0) > > +enum chips { max31827, max31828, max31829 }; > + > enum max31827_cnv { > MAX31827_CNV_1_DIV_64_HZ = 1, > MAX31827_CNV_1_DIV_32_HZ, > @@ -58,6 +81,7 @@ struct max31827_state { > struct mutex lock; > struct regmap *regmap; > bool enable; > + struct i2c_client *client; > }; > > static const struct regmap_config max31827_regmap = { > @@ -361,14 +385,93 @@ static int max31827_write(struct device *dev, enum hwmon_sensor_types type, > return -EOPNOTSUPP; > } > > -static int max31827_init_client(struct max31827_state *st) > +static const struct i2c_device_id max31827_i2c_ids[] = { > + { "max31827", max31827 }, > + { "max31828", max31828 }, > + { "max31829", max31829 }, > + { } > +}; > +MODULE_DEVICE_TABLE(i2c, max31827_i2c_ids); > + > +static int max31827_init_client(struct max31827_state *st, > + struct fwnode_handle *fwnode) > { > + bool prop; > + u32 data, lsb_idx; > + unsigned int res = 0; > + enum chips type; > + int ret; > + > st->enable = true; > + res |= MAX31827_DEVICE_ENABLE(1); > + > + res |= MAX31827_CONFIGURATION_RESOLUTION_MASK; > > - return regmap_update_bits(st->regmap, MAX31827_CONFIGURATION_REG, > - MAX31827_CONFIGURATION_1SHOT_MASK | > - MAX31827_CONFIGURATION_CNV_RATE_MASK, > - MAX31827_DEVICE_ENABLE(1)); > + prop = fwnode_property_read_bool(fwnode, "adi,comp-int"); > + res |= FIELD_PREP(MAX31827_CONFIGURATION_COMP_INT_MASK, prop); > + > + prop = fwnode_property_read_bool(fwnode, "adi,timeout-enable"); > + res |= FIELD_PREP(MAX31827_CONFIGURATION_TIMEOUT_MASK, !prop); > + > + if (st->client->dev.of_node) > + type = (enum chips)of_device_get_match_data(&st->client->dev); > + else > + type = i2c_match_id(max31827_i2c_ids, st->client)->driver_data; > + > + if (fwnode_property_present(fwnode, "adi,alrm-pol")) { > + ret = fwnode_property_read_u32(fwnode, "adi,alrm-pol", &data); > + if (ret) > + return ret; > + > + res |= FIELD_PREP(MAX31827_CONFIGURATION_ALRM_POL_MASK, !!data); > + } else { > + switch (type) { > + case max31827: > + case max31828: > + res |= FIELD_PREP(MAX31827_CONFIGURATION_ALRM_POL_MASK, > + 0x0); > + break; > + case max31829: > + res |= FIELD_PREP(MAX31827_CONFIGURATION_ALRM_POL_MASK, > + 0x1); > + break; > + default: > + return -EOPNOTSUPP; > + } > + } > + > + if (fwnode_property_present(fwnode, "adi,flt-q")) { > + ret = fwnode_property_read_u32(fwnode, "adi,flt-q", &data); > + if (ret) > + return ret; > + > + /* > + * Convert the desired fault queue into register bits. > + */ > + lsb_idx = max31827__bf_shf(data); > + if (lsb_idx > 3 || data != BIT(lsb_idx)) { > + dev_err(&st->client->dev, "Invalid data in fault queue\n"); > + return -EOPNOTSUPP; > + } > + > + res |= FIELD_PREP(MAX31827_CONFIGURATION_FLT_Q_MASK, lsb_idx); > + } else { > + switch (type) { > + case max31827: > + res |= FIELD_PREP(MAX31827_CONFIGURATION_FLT_Q_MASK, > + MAX31827_FLT_Q_1); > + break; > + case max31828: > + case max31829: > + res |= FIELD_PREP(MAX31827_CONFIGURATION_FLT_Q_MASK, > + MAX31827_FLT_Q_4); > + break; > + default: > + return -EOPNOTSUPP; > + } > + } > + > + return regmap_write(st->regmap, MAX31827_CONFIGURATION_REG, res); > } > > static const struct hwmon_channel_info *max31827_info[] = { > @@ -396,6 +499,7 @@ static int max31827_probe(struct i2c_client *client) > struct device *dev = &client->dev; > struct device *hwmon_dev; > struct max31827_state *st; > + struct fwnode_handle *fwnode; > int err; > > if (!i2c_check_functionality(client->adapter, I2C_FUNC_SMBUS_WORD_DATA)) > @@ -412,7 +516,10 @@ static int max31827_probe(struct i2c_client *client) > return dev_err_probe(dev, PTR_ERR(st->regmap), > "Failed to allocate regmap.\n"); > > - err = max31827_init_client(st); > + st->client = client; > + fwnode = dev_fwnode(dev); > + > + err = max31827_init_client(st, fwnode); > if (err) > return err; > > @@ -423,14 +530,19 @@ static int max31827_probe(struct i2c_client *client) > return PTR_ERR_OR_ZERO(hwmon_dev); > } > > -static const struct i2c_device_id max31827_i2c_ids[] = { > - { "max31827", 0 }, > - { } > -}; > -MODULE_DEVICE_TABLE(i2c, max31827_i2c_ids); > - > static const struct of_device_id max31827_of_match[] = { > - { .compatible = "adi,max31827" }, > + { > + .compatible = "adi,max31827", > + .data = (void *)max31827 > + }, > + { > + .compatible = "adi,max31828", > + .data = (void *)max31828 > + }, > + { > + .compatible = "adi,max31829", > + .data = (void *)max31829 > + }, > { } > }; > MODULE_DEVICE_TABLE(of, max31827_of_match);