---
Just in case someone is curious why the I state the datasheet is wrong
on the PWM frequency: The actual PWM frequency was verified by measuring
the output with an oscilloscope. Also you can write a '0' as the PWM
frequency which would result in div-by-zero; but what happens is that
the output frequency will be half the frequency of a setting of '1'.
Documentation/hwmon/lan966x.rst | 40 +++
drivers/hwmon/Kconfig | 12 +
drivers/hwmon/Makefile | 1 +
drivers/hwmon/lan966x-hwmon.c | 418 ++++++++++++++++++++++++++++++++
4 files changed, 471 insertions(+)
create mode 100644 Documentation/hwmon/lan966x.rst
create mode 100644 drivers/hwmon/lan966x-hwmon.c
diff --git a/Documentation/hwmon/lan966x.rst b/Documentation/hwmon/lan966x.rst
new file mode 100644
index 000000000000..1d1724afa5d2
--- /dev/null
+++ b/Documentation/hwmon/lan966x.rst
@@ -0,0 +1,40 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+Kernel driver lan966x-hwmon
+===========================
+
+Supported chips:
+
+ * Microchip LAN9668 (sensor in SoC)
+
+ Prefix: 'lan9668-hwmon'
+
+ Datasheet: https://microchip-ung.github.io/lan9668_reginfo
+
+Authors:
+
+ Michael Walle <michael@xxxxxxxx>
+
+Description
+-----------
+
+This driver implements support for the Microchip LAN9668 on-chip
+temperature sensor as well as its fan controller. It provides one
+temperature sensor and one fan controller. The temperature range
+of the sensor is specified from -40 to +125 degrees Celsius and
+its accuracy is +/- 5 degrees Celsius. The fan controller has a
+tacho input and a PWM output with a customizable PWM output
+frequency ranging from ~20Hz to ~650kHz.
+
+No alarms are supported by the SoC.
+
+The driver exports temperature values, fan tacho input and PWM
+settings via the following sysfs files:
+
+**temp1_input**
+
+**fan1_input**
+
+**pwm1**
+
+**pwm1_freq**
diff --git a/drivers/hwmon/Kconfig b/drivers/hwmon/Kconfig
index be9773270e53..052b37b78919 100644
--- a/drivers/hwmon/Kconfig
+++ b/drivers/hwmon/Kconfig
@@ -815,6 +815,18 @@ config SENSORS_POWR1220
This driver can also be built as a module. If so, the module
will be called powr1220.
+config SENSORS_LAN966X
+ tristate "Microchip LAN966x Hardware Monitoring"
+ depends on SOC_LAN966 || COMPILE_TEST
+ select REGMAP
+ select POLYNOMIAL
+ help
+ If you say yes here you get support for temperature monitoring
+ on the Microchip LAN966x SoC.
+
+ This driver can also be built as a module. If so, the module
+ will be called lan966x-hwmon.
+
config SENSORS_LINEAGE
tristate "Lineage Compact Power Line Power Entry Module"
depends on I2C
diff --git a/drivers/hwmon/Makefile b/drivers/hwmon/Makefile
index 8a03289e2aa4..51ca6956f8b7 100644
--- a/drivers/hwmon/Makefile
+++ b/drivers/hwmon/Makefile
@@ -100,6 +100,7 @@ obj-$(CONFIG_SENSORS_IT87) += it87.o
obj-$(CONFIG_SENSORS_JC42) += jc42.o
obj-$(CONFIG_SENSORS_K8TEMP) += k8temp.o
obj-$(CONFIG_SENSORS_K10TEMP) += k10temp.o
+obj-$(CONFIG_SENSORS_LAN966X) += lan966x-hwmon.o
obj-$(CONFIG_SENSORS_LINEAGE) += lineage-pem.o
obj-$(CONFIG_SENSORS_LOCHNAGAR) += lochnagar-hwmon.o
obj-$(CONFIG_SENSORS_LM63) += lm63.o
diff --git a/drivers/hwmon/lan966x-hwmon.c b/drivers/hwmon/lan966x-hwmon.c
new file mode 100644
index 000000000000..f41df053ac31
--- /dev/null
+++ b/drivers/hwmon/lan966x-hwmon.c
@@ -0,0 +1,418 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <linux/bitfield.h>
+#include <linux/clk.h>
+#include <linux/hwmon.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/mod_devicetable.h>
+#include <linux/platform_device.h>
+#include <linux/polynomial.h>
+#include <linux/regmap.h>
+
+/*
+ * The original translation formulae of the temperature (in degrees of Celsius)
+ * are as follows:
+ *
+ * T = -3.4627e-11*(N^4) + 1.1023e-7*(N^3) + -1.9165e-4*(N^2) +
+ * 3.0604e-1*(N^1) + -5.6197e1
+ *
+ * where [-56.197, 136.402]C and N = [0, 1023].
+ *
+ * They must be accordingly altered to be suitable for the integer arithmetics.
+ * The technique is called 'factor redistribution', which just makes sure the
+ * multiplications and divisions are made so to have a result of the operations
+ * within the integer numbers limit. In addition we need to translate the
+ * formulae to accept millidegrees of Celsius. Here what it looks like after
+ * the alterations:
+ *
+ * T = -34627e-12*(N^4) + 110230e-9*(N^3) + -191650e-6*(N^2) +
+ * 306040e-3*(N^1) + -56197
+ *
+ * where T = [-56197, 136402]mC and N = [0, 1023].
+ */
+
+static const struct polynomial poly_N_to_temp = {
+ .terms = {
+ {4, -34627, 1000, 1},
+ {3, 110230, 1000, 1},
+ {2, -191650, 1000, 1},
+ {1, 306040, 1000, 1},
+ {0, -56197, 1, 1}
+ }
+};
+
+#define PVT_SENSOR_CTRL 0x0 /* unused */
+#define PVT_SENSOR_CFG 0x4
+#define SENSOR_CFG_CLK_CFG GENMASK(27, 20)
+#define SENSOR_CFG_TRIM_VAL GENMASK(13, 9)
+#define SENSOR_CFG_SAMPLE_ENA BIT(8)
+#define SENSOR_CFG_START_CAPTURE BIT(7)
+#define SENSOR_CFG_CONTINIOUS_MODE BIT(6)
+#define SENSOR_CFG_PSAMPLE_ENA GENMASK(1, 0)
+#define PVT_SENSOR_STAT 0x8
+#define SENSOR_STAT_DATA_VALID BIT(10)
+#define SENSOR_STAT_DATA GENMASK(9, 0)
+
+#define FAN_CFG 0x0
+#define FAN_CFG_DUTY_CYCLE GENMASK(23, 16)
+#define INV_POL BIT(3)
+#define GATE_ENA BIT(2)
+#define PWM_OPEN_COL_ENA BIT(1)
+#define FAN_STAT_CFG BIT(0)
+#define FAN_PWM_FREQ 0x4
+#define FAN_PWM_CYC_10US GENMASK(25, 15)
+#define FAN_PWM_FREQ_FREQ GENMASK(14, 0)
+#define FAN_CNT 0xc
+#define FAN_CNT_DATA GENMASK(15, 0)
+
+#define LAN966X_PVT_CLK 1200000 /* 1.2 MHz */
+
+struct lan966x_hwmon {
+ struct regmap *regmap_pvt;
+ struct regmap *regmap_fan;
+ struct clk *clk;
+ unsigned long clk_rate;
+};
+
+static int lan966x_hwmon_read_temp(struct device *dev, long *val)
+{
+ struct lan966x_hwmon *hwmon = dev_get_drvdata(dev);
+ unsigned int data;
+ int ret;
+
+ ret = regmap_read(hwmon->regmap_pvt, PVT_SENSOR_STAT, &data);
+ if (ret < 0)
+ return ret;
+
+ if (!(data & SENSOR_STAT_DATA_VALID))
+ return -ENODATA;
+
+ *val = polynomial_calc(&poly_N_to_temp,
+ FIELD_GET(SENSOR_STAT_DATA, data));
+
+ return 0;
+}
+
+static int lan966x_hwmon_read_fan(struct device *dev, long *val)
+{
+ struct lan966x_hwmon *hwmon = dev_get_drvdata(dev);
+ unsigned int data;
+ int ret;
+
+ ret = regmap_read(hwmon->regmap_fan, FAN_CNT, &data);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Data is given in pulses per second. Assume two pulses
+ * per revolution.
+ */
+ *val = FIELD_GET(FAN_CNT_DATA, data) * 60 / 2;
+
+ return 0;
+}
+
+static int lan966x_hwmon_read_pwm(struct device *dev, long *val)
+{
+ struct lan966x_hwmon *hwmon = dev_get_drvdata(dev);
+ unsigned int data;
+ int ret;
+
+ ret = regmap_read(hwmon->regmap_fan, FAN_CFG, &data);
+ if (ret < 0)
+ return ret;
+
+ *val = FIELD_GET(FAN_CFG_DUTY_CYCLE, data);
+
+ return 0;
+}
+
+static int lan966x_hwmon_read_pwm_freq(struct device *dev, long *val)
+{
+ struct lan966x_hwmon *hwmon = dev_get_drvdata(dev);
+ unsigned long tmp;
+ unsigned int data;
+ int ret;
+
+ ret = regmap_read(hwmon->regmap_fan, FAN_PWM_FREQ, &data);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * Datasheet says it is sys_clk / 256 / pwm_freq. But in reality
+ * it is sys_clk / 256 / (pwm_freq + 1).
+ */
+ data = FIELD_GET(FAN_PWM_FREQ_FREQ, data) + 1;
+ tmp = DIV_ROUND_CLOSEST(hwmon->clk_rate, 256);
+ *val = DIV_ROUND_CLOSEST(tmp, data);
+
+ return 0;
+}
+
+static int lan966x_hwmon_read(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long *val)
+{
+ switch (type) {
+ case hwmon_temp:
+ return lan966x_hwmon_read_temp(dev, val);
+ case hwmon_fan:
+ return lan966x_hwmon_read_fan(dev, val);
+ case hwmon_pwm:
+ switch (attr) {
+ case hwmon_pwm_input:
+ return lan966x_hwmon_read_pwm(dev, val);
+ case hwmon_pwm_freq:
+ return lan966x_hwmon_read_pwm_freq(dev, val);
+ default:
+ return -EOPNOTSUPP;
+ }
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static int lan966x_hwmon_write_pwm(struct device *dev, long val)
+{
+ struct lan966x_hwmon *hwmon = dev_get_drvdata(dev);
+
+ if (val < 0 || val > 255)
+ return -EINVAL;
+
+ return regmap_update_bits(hwmon->regmap_fan, FAN_CFG,
+ FAN_CFG_DUTY_CYCLE,
+ FIELD_PREP(FAN_CFG_DUTY_CYCLE, val));
+}
+
+static int lan966x_hwmon_write_pwm_freq(struct device *dev, long val)
+{
+ struct lan966x_hwmon *hwmon = dev_get_drvdata(dev);
+
+ if (val <= 0)
+ return -EINVAL;
+
+ val = DIV_ROUND_CLOSEST(hwmon->clk_rate, val);
+ val = DIV_ROUND_CLOSEST(val, 256) - 1;
+ val = clamp_val(val, 0, FAN_PWM_FREQ_FREQ);
+
+ return regmap_update_bits(hwmon->regmap_fan, FAN_PWM_FREQ,
+ FAN_PWM_FREQ_FREQ,
+ FIELD_PREP(FAN_PWM_FREQ_FREQ, val));
+}
+
+static int lan966x_hwmon_write(struct device *dev, enum hwmon_sensor_types type,
+ u32 attr, int channel, long val)
+{
+ switch (type) {
+ case hwmon_pwm:
+ switch (attr) {
+ case hwmon_pwm_input:
+ return lan966x_hwmon_write_pwm(dev, val);
+ case hwmon_pwm_freq:
+ return lan966x_hwmon_write_pwm_freq(dev, val);
+ default:
+ return -EOPNOTSUPP;
+ }
+ default:
+ return -EOPNOTSUPP;
+ }
+}
+
+static umode_t lan966x_hwmon_is_visible(const void *data,
+ enum hwmon_sensor_types type,
+ u32 attr, int channel)
+{
+ umode_t mode = 0;
+
+ switch (type) {
+ case hwmon_temp:
+ switch (attr) {
+ case hwmon_temp_input:
+ mode = 0444;
+ break;
+ default:
+ break;
+ }
+ break;
+ case hwmon_fan:
+ switch (attr) {
+ case hwmon_fan_input:
+ mode = 0444;
+ break;
+ default:
+ break;
+ }
+ break;
+ case hwmon_pwm:
+ switch (attr) {
+ case hwmon_pwm_input:
+ case hwmon_pwm_freq:
+ mode = 0644;
+ break;
+ default:
+ break;
+ }
+ break;
+ default:
+ break;
+ }
+
+ return mode;
+}
+
+static const struct hwmon_channel_info *lan966x_hwmon_info[] = {
+ HWMON_CHANNEL_INFO(chip, HWMON_C_REGISTER_TZ),
+ HWMON_CHANNEL_INFO(temp, HWMON_T_INPUT),
+ HWMON_CHANNEL_INFO(fan, HWMON_F_INPUT),
+ HWMON_CHANNEL_INFO(pwm, HWMON_PWM_INPUT | HWMON_PWM_FREQ),
+ NULL
+};
+
+static const struct hwmon_ops lan966x_hwmon_ops = {
+ .is_visible = lan966x_hwmon_is_visible,
+ .read = lan966x_hwmon_read,
+ .write = lan966x_hwmon_write,
+};
+
+static const struct hwmon_chip_info lan966x_hwmon_chip_info = {
+ .ops = &lan966x_hwmon_ops,
+ .info = lan966x_hwmon_info,
+};
+
+static void lan966x_hwmon_disable(void *data)
+{
+ struct lan966x_hwmon *hwmon = data;
+
+ regmap_update_bits(hwmon->regmap_pvt, PVT_SENSOR_CFG,
+ SENSOR_CFG_SAMPLE_ENA | SENSOR_CFG_CONTINIOUS_MODE,
+ 0);
+}
+
+static int lan966x_hwmon_enable(struct device *dev,
+ struct lan966x_hwmon *hwmon)
+{
+ unsigned int mask = SENSOR_CFG_CLK_CFG |
+ SENSOR_CFG_SAMPLE_ENA |
+ SENSOR_CFG_START_CAPTURE |
+ SENSOR_CFG_CONTINIOUS_MODE |
+ SENSOR_CFG_PSAMPLE_ENA;
+ unsigned int val;
+ unsigned int div;
+ int ret;
+
+ /* enable continuous mode */
+ val = SENSOR_CFG_SAMPLE_ENA | SENSOR_CFG_CONTINIOUS_MODE;
+
+ /* set PVT clock to be between 1.15 and 1.25 MHz */
+ div = DIV_ROUND_CLOSEST(hwmon->clk_rate, LAN966X_PVT_CLK);
+ val |= FIELD_PREP(SENSOR_CFG_CLK_CFG, div);
+
+ ret = regmap_update_bits(hwmon->regmap_pvt, PVT_SENSOR_CFG,
+ mask, val);
+ if (ret)
+ return ret;
+
+ return devm_add_action_or_reset(dev, lan966x_hwmon_disable, hwmon);
+}
+
+static struct regmap *lan966x_init_regmap(struct platform_device *pdev,
+ const char *name)
+{
+ struct regmap_config regmap_config = {
+ .reg_bits = 32,
+ .reg_stride = 4,
+ .val_bits = 32,
+ };
+ void __iomem *base;
+
+ base = devm_platform_ioremap_resource_byname(pdev, name);
+ if (IS_ERR(base))
+ return ERR_CAST(base);
+
+ regmap_config.name = name;
+
+ return devm_regmap_init_mmio(&pdev->dev, base, ®map_config);
+}
+
+static void lan966x_clk_disable(void *data)
+{
+ struct lan966x_hwmon *hwmon = data;
+
+ clk_disable_unprepare(hwmon->clk);
+}
+
+static int lan966x_clk_enable(struct device *dev, struct lan966x_hwmon *hwmon)
+{
+ int ret;
+
+ ret = clk_prepare_enable(hwmon->clk);
+ if (ret)
+ return ret;
+
+ return devm_add_action_or_reset(dev, lan966x_clk_disable, hwmon);
+}
+
+static int lan966x_hwmon_probe(struct platform_device *pdev)
+{
+ struct device *dev = &pdev->dev;
+ struct lan966x_hwmon *hwmon;
+ struct device *hwmon_dev;
+ int ret;
+
+ hwmon = devm_kzalloc(dev, sizeof(*hwmon), GFP_KERNEL);
+ if (!hwmon)
+ return -ENOMEM;
+
+ hwmon->clk = devm_clk_get(dev, NULL);
+ if (IS_ERR(hwmon->clk))
+ return dev_err_probe(dev, PTR_ERR(hwmon->clk),
+ "failed to get clock\n");
+
+ ret = lan966x_clk_enable(dev, hwmon);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to enable clock\n");
+
+ hwmon->clk_rate = clk_get_rate(hwmon->clk);
+
+ hwmon->regmap_pvt = lan966x_init_regmap(pdev, "pvt");
+ if (IS_ERR(hwmon->regmap_pvt))
+ return dev_err_probe(dev, PTR_ERR(hwmon->regmap_pvt),
+ "failed to get regmap for PVT registers\n");
+
+ hwmon->regmap_fan = lan966x_init_regmap(pdev, "fan");
+ if (IS_ERR(hwmon->regmap_fan))
+ return dev_err_probe(dev, PTR_ERR(hwmon->regmap_fan),
+ "failed to get regmap for fan registers\n");
+
+ ret = lan966x_hwmon_enable(dev, hwmon);
+ if (ret)
+ return dev_err_probe(dev, ret, "failed to enable sensor\n");
+
+ hwmon_dev = devm_hwmon_device_register_with_info(&pdev->dev,
+ "lan966x_hwmon", hwmon,
+ &lan966x_hwmon_chip_info, NULL);
+ if (IS_ERR(hwmon_dev))
+ return dev_err_probe(dev, PTR_ERR(hwmon_dev),
+ "failed to register hwmon device\n");
+
+ return 0;
+}
+
+static const struct of_device_id lan966x_hwmon_of_match[] = {
+ { .compatible = "microchip,lan9668-hwmon" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, lan966x_hwmon_of_match);
+
+static struct platform_driver lan966x_hwmon_driver = {
+ .probe = lan966x_hwmon_probe,
+ .driver = {
+ .name = "lan966x-hwmon",
+ .of_match_table = lan966x_hwmon_of_match,
+ },
+};
+module_platform_driver(lan966x_hwmon_driver);
+
+MODULE_DESCRIPTION("LAN966x Hardware Monitoring Driver");
+MODULE_AUTHOR("Michael Walle <michael@xxxxxxxx>");
+MODULE_LICENSE("GPL");
