// SPDX-License-Identifier: GPL-2.0 /* * Lochnagar hardware monitoring features * * Copyright (c) 2016-2019 Cirrus Logic, Inc. and * Cirrus Logic International Semiconductor Ltd. * * Author: Lucas Tanure */ #include #include #include #include #include #include #include #include #include #include #include #include #define LN2_MAX_NSAMPLE 1023 #define LN2_SAMPLE_US 1670 #define LN2_CURR_UNITS 1000 #define LN2_VOLT_UNITS 1000 #define LN2_TEMP_UNITS 1000 #define LN2_PWR_UNITS 1000000 static const char * const lochnagar_chan_names[] = { "DBVDD1", "1V8 DSP", "1V8 CDC", "VDDCORE DSP", "AVDD 1V8", "SYSVDD", "VDDCORE CDC", "MICVDD", }; struct lochnagar_hwmon { struct regmap *regmap; long power_nsamples[ARRAY_SIZE(lochnagar_chan_names)]; /* Lock to ensure only a single sensor is read at a time */ struct mutex sensor_lock; }; enum lochnagar_measure_mode { LN2_CURR = 0, LN2_VOLT, LN2_TEMP, }; /** * float_to_long - Convert ieee754 reading from hardware to an integer * * @data: Value read from the hardware * @precision: Units to multiply up to eg. 1000 = milli, 1000000 = micro * * Return: Converted integer reading * * Depending on the measurement type the hardware returns an ieee754 * floating point value in either volts, amps or celsius. This function * will convert that into an integer in a smaller unit such as micro-amps * or milli-celsius. The hardware does not return NaN, so consideration of * that is not required. */ static long float_to_long(u32 data, u32 precision) { u64 man = data & 0x007FFFFF; int exp = ((data & 0x7F800000) >> 23) - 127 - 23; bool negative = data & 0x80000000; long result; man = (man + (1 << 23)) * precision; if (fls64(man) + exp > (int)sizeof(long) * 8 - 1) result = LONG_MAX; else if (exp < 0) result = (man + (1ull << (-exp - 1))) >> -exp; else result = man << exp; return negative ? -result : result; } static int do_measurement(struct regmap *regmap, int chan, enum lochnagar_measure_mode mode, int nsamples) { unsigned int val; int ret; chan = 1 << (chan + LOCHNAGAR2_IMON_MEASURED_CHANNELS_SHIFT); ret = regmap_write(regmap, LOCHNAGAR2_IMON_CTRL1, LOCHNAGAR2_IMON_ENA_MASK | chan | mode); if (ret < 0) return ret; ret = regmap_write(regmap, LOCHNAGAR2_IMON_CTRL2, nsamples); if (ret < 0) return ret; ret = regmap_write(regmap, LOCHNAGAR2_IMON_CTRL3, LOCHNAGAR2_IMON_CONFIGURE_MASK); if (ret < 0) return ret; ret = regmap_read_poll_timeout(regmap, LOCHNAGAR2_IMON_CTRL3, val, val & LOCHNAGAR2_IMON_DONE_MASK, 1000, 10000); if (ret < 0) return ret; ret = regmap_write(regmap, LOCHNAGAR2_IMON_CTRL3, LOCHNAGAR2_IMON_MEASURE_MASK); if (ret < 0) return ret; /* * Actual measurement time is ~1.67mS per sample, approximate this * with a 1.5mS per sample msleep and then poll for success up to * ~0.17mS * 1023 (LN2_MAX_NSAMPLES). Normally for smaller values * of nsamples the poll will complete on the first loop due to * other latency in the system. */ msleep((nsamples * 3) / 2); ret = regmap_read_poll_timeout(regmap, LOCHNAGAR2_IMON_CTRL3, val, val & LOCHNAGAR2_IMON_DONE_MASK, 5000, 200000); if (ret < 0) return ret; return regmap_write(regmap, LOCHNAGAR2_IMON_CTRL3, 0); } static int request_data(struct regmap *regmap, int chan, u32 *data) { unsigned int val; int ret; ret = regmap_write(regmap, LOCHNAGAR2_IMON_CTRL4, LOCHNAGAR2_IMON_DATA_REQ_MASK | chan << LOCHNAGAR2_IMON_CH_SEL_SHIFT); if (ret < 0) return ret; ret = regmap_read_poll_timeout(regmap, LOCHNAGAR2_IMON_CTRL4, val, val & LOCHNAGAR2_IMON_DATA_RDY_MASK, 1000, 10000); if (ret < 0) return ret; ret = regmap_read(regmap, LOCHNAGAR2_IMON_DATA1, &val); if (ret < 0) return ret; *data = val << 16; ret = regmap_read(regmap, LOCHNAGAR2_IMON_DATA2, &val); if (ret < 0) return ret; *data |= val; return regmap_write(regmap, LOCHNAGAR2_IMON_CTRL4, 0); } static int read_sensor(struct device *dev, int chan, enum lochnagar_measure_mode mode, int nsamples, unsigned int precision, long *val) { struct lochnagar_hwmon *priv = dev_get_drvdata(dev); struct regmap *regmap = priv->regmap; u32 data; int ret; mutex_lock(&priv->sensor_lock); ret = do_measurement(regmap, chan, mode, nsamples); if (ret < 0) { dev_err(dev, "Failed to perform measurement: %d\n", ret); goto error; } ret = request_data(regmap, chan, &data); if (ret < 0) { dev_err(dev, "Failed to read measurement: %d\n", ret); goto error; } *val = float_to_long(data, precision); error: mutex_unlock(&priv->sensor_lock); return ret; } static int read_power(struct device *dev, int chan, long *val) { struct lochnagar_hwmon *priv = dev_get_drvdata(dev); int nsamples = priv->power_nsamples[chan]; u64 power; int ret; if (!strcmp("SYSVDD", lochnagar_chan_names[chan])) { power = 5 * LN2_PWR_UNITS; } else { ret = read_sensor(dev, chan, LN2_VOLT, 1, LN2_PWR_UNITS, val); if (ret < 0) return ret; power = abs(*val); } ret = read_sensor(dev, chan, LN2_CURR, nsamples, LN2_PWR_UNITS, val); if (ret < 0) return ret; power *= abs(*val); power = DIV_ROUND_CLOSEST_ULL(power, LN2_PWR_UNITS); if (power > LONG_MAX) *val = LONG_MAX; else *val = power; return 0; } static umode_t lochnagar_is_visible(const void *drvdata, enum hwmon_sensor_types type, u32 attr, int chan) { switch (type) { case hwmon_in: if (!strcmp("SYSVDD", lochnagar_chan_names[chan])) return 0; break; case hwmon_power: if (attr == hwmon_power_average_interval) return 0644; break; default: break; } return 0444; } static int lochnagar_read(struct device *dev, enum hwmon_sensor_types type, u32 attr, int chan, long *val) { struct lochnagar_hwmon *priv = dev_get_drvdata(dev); int interval; switch (type) { case hwmon_in: return read_sensor(dev, chan, LN2_VOLT, 1, LN2_VOLT_UNITS, val); case hwmon_curr: return read_sensor(dev, chan, LN2_CURR, 1, LN2_CURR_UNITS, val); case hwmon_temp: return read_sensor(dev, chan, LN2_TEMP, 1, LN2_TEMP_UNITS, val); case hwmon_power: switch (attr) { case hwmon_power_average: return read_power(dev, chan, val); case hwmon_power_average_interval: interval = priv->power_nsamples[chan] * LN2_SAMPLE_US; *val = DIV_ROUND_CLOSEST(interval, 1000); return 0; default: return -EOPNOTSUPP; } default: return -EOPNOTSUPP; } } static int lochnagar_read_string(struct device *dev, enum hwmon_sensor_types type, u32 attr, int chan, const char **str) { switch (type) { case hwmon_in: case hwmon_curr: case hwmon_power: *str = lochnagar_chan_names[chan]; return 0; default: return -EOPNOTSUPP; } } static int lochnagar_write(struct device *dev, enum hwmon_sensor_types type, u32 attr, int chan, long val) { struct lochnagar_hwmon *priv = dev_get_drvdata(dev); if (type != hwmon_power || attr != hwmon_power_average_interval) return -EOPNOTSUPP; val = clamp_t(long, val, 1, (LN2_MAX_NSAMPLE * LN2_SAMPLE_US) / 1000); val = DIV_ROUND_CLOSEST(val * 1000, LN2_SAMPLE_US); priv->power_nsamples[chan] = val; return 0; } static const struct hwmon_ops lochnagar_ops = { .is_visible = lochnagar_is_visible, .read = lochnagar_read, .read_string = lochnagar_read_string, .write = lochnagar_write, }; static const struct hwmon_channel_info *lochnagar_info[] = { HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT), HWMON_CHANNEL_INFO(in, HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL, HWMON_I_INPUT | HWMON_I_LABEL), HWMON_CHANNEL_INFO(curr, HWMON_C_INPUT | HWMON_C_LABEL, HWMON_C_INPUT | HWMON_C_LABEL, HWMON_C_INPUT | HWMON_C_LABEL, HWMON_C_INPUT | HWMON_C_LABEL, HWMON_C_INPUT | HWMON_C_LABEL, HWMON_C_INPUT | HWMON_C_LABEL, HWMON_C_INPUT | HWMON_C_LABEL, HWMON_C_INPUT | HWMON_C_LABEL), HWMON_CHANNEL_INFO(power, HWMON_P_AVERAGE | HWMON_P_AVERAGE_INTERVAL | HWMON_P_LABEL, HWMON_P_AVERAGE | HWMON_P_AVERAGE_INTERVAL | HWMON_P_LABEL, HWMON_P_AVERAGE | HWMON_P_AVERAGE_INTERVAL | HWMON_P_LABEL, HWMON_P_AVERAGE | HWMON_P_AVERAGE_INTERVAL | HWMON_P_LABEL, HWMON_P_AVERAGE | HWMON_P_AVERAGE_INTERVAL | HWMON_P_LABEL, HWMON_P_AVERAGE | HWMON_P_AVERAGE_INTERVAL | HWMON_P_LABEL, HWMON_P_AVERAGE | HWMON_P_AVERAGE_INTERVAL | HWMON_P_LABEL, HWMON_P_AVERAGE | HWMON_P_AVERAGE_INTERVAL | HWMON_P_LABEL), NULL }; static const struct hwmon_chip_info lochnagar_chip_info = { .ops = &lochnagar_ops, .info = lochnagar_info, }; static const struct of_device_id lochnagar_of_match[] = { { .compatible = "cirrus,lochnagar2-hwmon" }, {} }; MODULE_DEVICE_TABLE(of, lochnagar_of_match); static int lochnagar_hwmon_probe(struct platform_device *pdev) { struct device *dev = &pdev->dev; struct device *hwmon_dev; struct lochnagar_hwmon *priv; int i; priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); if (!priv) return -ENOMEM; mutex_init(&priv->sensor_lock); priv->regmap = dev_get_regmap(dev->parent, NULL); if (!priv->regmap) { dev_err(dev, "No register map found\n"); return -EINVAL; } for (i = 0; i < ARRAY_SIZE(priv->power_nsamples); i++) priv->power_nsamples[i] = 96; hwmon_dev = devm_hwmon_device_register_with_info(dev, "Lochnagar", priv, &lochnagar_chip_info, NULL); return PTR_ERR_OR_ZERO(hwmon_dev); } static struct platform_driver lochnagar_hwmon_driver = { .driver = { .name = "lochnagar-hwmon", .of_match_table = lochnagar_of_match, }, .probe = lochnagar_hwmon_probe, }; module_platform_driver(lochnagar_hwmon_driver); MODULE_AUTHOR("Lucas Tanure "); MODULE_DESCRIPTION("Lochnagar hardware monitoring features"); MODULE_LICENSE("GPL");