Adding upstream version 6.1.76.upstream/6.1.76upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 620 insertions, 0 deletions

diff --git a/drivers/hwmon/mlxreg-fan.c b/drivers/hwmon/mlxreg-fan.c
new file mode 100644
index 000000000..96017cc8d
--- /dev/null
+++ b/drivers/hwmon/mlxreg-fan.c
@@ -0,0 +1,620 @@
+// SPDX-License-Identifier: (GPL-2.0 OR BSD-3-Clause)
+//
+// Copyright (c) 2018 Mellanox Technologies. All rights reserved.
+// Copyright (c) 2018 Vadim Pasternak <vadimp@mellanox.com>
+
+#include <linux/bitops.h>
+#include <linux/device.h>
+#include <linux/hwmon.h>
+#include <linux/module.h>
+#include <linux/platform_data/mlxreg.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/thermal.h>
+
+#define MLXREG_FAN_MAX_TACHO		14
+#define MLXREG_FAN_MAX_PWM		4
+#define MLXREG_FAN_PWM_NOT_CONNECTED	0xff
+#define MLXREG_FAN_MAX_STATE		10
+#define MLXREG_FAN_MIN_DUTY		51	/* 20% */
+#define MLXREG_FAN_MAX_DUTY		255	/* 100% */
+#define MLXREG_FAN_SPEED_MIN_LEVEL		2	/* 20 percent */
+#define MLXREG_FAN_TACHO_SAMPLES_PER_PULSE_DEF	44
+#define MLXREG_FAN_TACHO_DIV_MIN		283
+#define MLXREG_FAN_TACHO_DIV_DEF		(MLXREG_FAN_TACHO_DIV_MIN * 4)
+#define MLXREG_FAN_TACHO_DIV_SCALE_MAX	64
+/*
+ * FAN datasheet defines the formula for RPM calculations as RPM = 15/t-high.
+ * The logic in a programmable device measures the time t-high by sampling the
+ * tachometer every t-sample (with the default value 11.32 uS) and increment
+ * a counter (N) as long as the pulse has not change:
+ * RPM = 15 / (t-sample * (K + Regval)), where:
+ * Regval: is the value read from the programmable device register;
+ *  - 0xff - represents tachometer fault;
+ *  - 0xfe - represents tachometer minimum value , which is 4444 RPM;
+ *  - 0x00 - represents tachometer maximum value , which is 300000 RPM;
+ * K: is 44 and it represents the minimum allowed samples per pulse;
+ * N: is equal K + Regval;
+ * In order to calculate RPM from the register value the following formula is
+ * used: RPM = 15 / ((Regval + K) * 11.32) * 10^(-6)), which in  the
+ * default case is modified to:
+ * RPM = 15000000 * 100 / ((Regval + 44) * 1132);
+ * - for Regval 0x00, RPM will be 15000000 * 100 / (44 * 1132) = 30115;
+ * - for Regval 0xfe, RPM will be 15000000 * 100 / ((254 + 44) * 1132) = 4446;
+ * In common case the formula is modified to:
+ * RPM = 15000000 * 100 / ((Regval + samples) * divider).
+ */
+#define MLXREG_FAN_GET_RPM(rval, d, s)	(DIV_ROUND_CLOSEST(15000000 * 100, \
+					 ((rval) + (s)) * (d)))
+#define MLXREG_FAN_GET_FAULT(val, mask) ((val) == (mask))
+#define MLXREG_FAN_PWM_DUTY2STATE(duty)	(DIV_ROUND_CLOSEST((duty) *	\
+					 MLXREG_FAN_MAX_STATE,		\
+					 MLXREG_FAN_MAX_DUTY))
+#define MLXREG_FAN_PWM_STATE2DUTY(stat)	(DIV_ROUND_CLOSEST((stat) *	\
+					 MLXREG_FAN_MAX_DUTY,		\
+					 MLXREG_FAN_MAX_STATE))
+
+struct mlxreg_fan;
+
+/*
+ * struct mlxreg_fan_tacho - tachometer data (internal use):
+ *
+ * @connected: indicates if tachometer is connected;
+ * @reg: register offset;
+ * @mask: fault mask;
+ * @prsnt: present register offset;
+ */
+struct mlxreg_fan_tacho {
+	bool connected;
+	u32 reg;
+	u32 mask;
+	u32 prsnt;
+};
+
+/*
+ * struct mlxreg_fan_pwm - PWM data (internal use):
+ *
+ * @fan: private data;
+ * @connected: indicates if PWM is connected;
+ * @reg: register offset;
+ * @cooling: cooling device levels;
+ * @last_hwmon_state: last cooling state set by hwmon subsystem;
+ * @last_thermal_state: last cooling state set by thermal subsystem;
+ * @cdev: cooling device;
+ */
+struct mlxreg_fan_pwm {
+	struct mlxreg_fan *fan;
+	bool connected;
+	u32 reg;
+	unsigned long last_hwmon_state;
+	unsigned long last_thermal_state;
+	struct thermal_cooling_device *cdev;
+};
+
+/*
+ * struct mlxreg_fan - private data (internal use):
+ *
+ * @dev: basic device;
+ * @regmap: register map of parent device;
+ * @tacho: tachometer data;
+ * @pwm: PWM data;
+ * @tachos_per_drwr - number of tachometers per drawer;
+ * @samples: minimum allowed samples per pulse;
+ * @divider: divider value for tachometer RPM calculation;
+ */
+struct mlxreg_fan {
+	struct device *dev;
+	void *regmap;
+	struct mlxreg_core_platform_data *pdata;
+	struct mlxreg_fan_tacho tacho[MLXREG_FAN_MAX_TACHO];
+	struct mlxreg_fan_pwm pwm[MLXREG_FAN_MAX_PWM];
+	int tachos_per_drwr;
+	int samples;
+	int divider;
+};
+
+static int mlxreg_fan_set_cur_state(struct thermal_cooling_device *cdev,
+				    unsigned long state);
+
+static int
+mlxreg_fan_read(struct device *dev, enum hwmon_sensor_types type, u32 attr,
+		int channel, long *val)
+{
+	struct mlxreg_fan *fan = dev_get_drvdata(dev);
+	struct mlxreg_fan_tacho *tacho;
+	struct mlxreg_fan_pwm *pwm;
+	u32 regval;
+	int err;
+
+	switch (type) {
+	case hwmon_fan:
+		tacho = &fan->tacho[channel];
+		switch (attr) {
+		case hwmon_fan_input:
+			/*
+			 * Check FAN presence: FAN related bit in presence register is one,
+			 * if FAN is physically connected, zero - otherwise.
+			 */
+			if (tacho->prsnt && fan->tachos_per_drwr) {
+				err = regmap_read(fan->regmap, tacho->prsnt, &regval);
+				if (err)
+					return err;
+
+				/*
+				 * Map channel to presence bit - drawer can be equipped with
+				 * one or few FANs, while presence is indicated per drawer.
+				 */
+				if (BIT(channel / fan->tachos_per_drwr) & regval) {
+					/* FAN is not connected - return zero for FAN speed. */
+					*val = 0;
+					return 0;
+				}
+			}
+
+			err = regmap_read(fan->regmap, tacho->reg, &regval);
+			if (err)
+				return err;
+
+			if (MLXREG_FAN_GET_FAULT(regval, tacho->mask)) {
+				/* FAN is broken - return zero for FAN speed. */
+				*val = 0;
+				return 0;
+			}
+
+			*val = MLXREG_FAN_GET_RPM(regval, fan->divider,
+						  fan->samples);
+			break;
+
+		case hwmon_fan_fault:
+			err = regmap_read(fan->regmap, tacho->reg, &regval);
+			if (err)
+				return err;
+
+			*val = MLXREG_FAN_GET_FAULT(regval, tacho->mask);
+			break;
+
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+
+	case hwmon_pwm:
+		pwm = &fan->pwm[channel];
+		switch (attr) {
+		case hwmon_pwm_input:
+			err = regmap_read(fan->regmap, pwm->reg, &regval);
+			if (err)
+				return err;
+
+			*val = regval;
+			break;
+
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+static int
+mlxreg_fan_write(struct device *dev, enum hwmon_sensor_types type, u32 attr,
+		 int channel, long val)
+{
+	struct mlxreg_fan *fan = dev_get_drvdata(dev);
+	struct mlxreg_fan_pwm *pwm;
+
+	switch (type) {
+	case hwmon_pwm:
+		switch (attr) {
+		case hwmon_pwm_input:
+			if (val < MLXREG_FAN_MIN_DUTY ||
+			    val > MLXREG_FAN_MAX_DUTY)
+				return -EINVAL;
+			pwm = &fan->pwm[channel];
+			/* If thermal is configured - handle PWM limit setting. */
+			if (IS_REACHABLE(CONFIG_THERMAL)) {
+				pwm->last_hwmon_state = MLXREG_FAN_PWM_DUTY2STATE(val);
+				/*
+				 * Update PWM only in case requested state is not less than the
+				 * last thermal state.
+				 */
+				if (pwm->last_hwmon_state >= pwm->last_thermal_state)
+					return mlxreg_fan_set_cur_state(pwm->cdev,
+									pwm->last_hwmon_state);
+				return 0;
+			}
+			return regmap_write(fan->regmap, pwm->reg, val);
+		default:
+			return -EOPNOTSUPP;
+		}
+		break;
+
+	default:
+		return -EOPNOTSUPP;
+	}
+
+	return -EOPNOTSUPP;
+}
+
+static umode_t
+mlxreg_fan_is_visible(const void *data, enum hwmon_sensor_types type, u32 attr,
+		      int channel)
+{
+	switch (type) {
+	case hwmon_fan:
+		if (!(((struct mlxreg_fan *)data)->tacho[channel].connected))
+			return 0;
+
+		switch (attr) {
+		case hwmon_fan_input:
+		case hwmon_fan_fault:
+			return 0444;
+		default:
+			break;
+		}
+		break;
+
+	case hwmon_pwm:
+		if (!(((struct mlxreg_fan *)data)->pwm[channel].connected))
+			return 0;
+
+		switch (attr) {
+		case hwmon_pwm_input:
+			return 0644;
+		default:
+			break;
+		}
+		break;
+
+	default:
+		break;
+	}
+
+	return 0;
+}
+
+static char *mlxreg_fan_name[] = {
+	"mlxreg_fan",
+	"mlxreg_fan1",
+	"mlxreg_fan2",
+	"mlxreg_fan3",
+};
+
+static const struct hwmon_channel_info *mlxreg_fan_hwmon_info[] = {
+	HWMON_CHANNEL_INFO(fan,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT,
+			   HWMON_F_INPUT | HWMON_F_FAULT),
+	HWMON_CHANNEL_INFO(pwm,
+			   HWMON_PWM_INPUT,
+			   HWMON_PWM_INPUT,
+			   HWMON_PWM_INPUT,
+			   HWMON_PWM_INPUT),
+	NULL
+};
+
+static const struct hwmon_ops mlxreg_fan_hwmon_hwmon_ops = {
+	.is_visible = mlxreg_fan_is_visible,
+	.read = mlxreg_fan_read,
+	.write = mlxreg_fan_write,
+};
+
+static const struct hwmon_chip_info mlxreg_fan_hwmon_chip_info = {
+	.ops = &mlxreg_fan_hwmon_hwmon_ops,
+	.info = mlxreg_fan_hwmon_info,
+};
+
+static int mlxreg_fan_get_max_state(struct thermal_cooling_device *cdev,
+				    unsigned long *state)
+{
+	*state = MLXREG_FAN_MAX_STATE;
+	return 0;
+}
+
+static int mlxreg_fan_get_cur_state(struct thermal_cooling_device *cdev,
+				    unsigned long *state)
+
+{
+	struct mlxreg_fan_pwm *pwm = cdev->devdata;
+	struct mlxreg_fan *fan = pwm->fan;
+	u32 regval;
+	int err;
+
+	err = regmap_read(fan->regmap, pwm->reg, &regval);
+	if (err) {
+		dev_err(fan->dev, "Failed to query PWM duty\n");
+		return err;
+	}
+
+	*state = MLXREG_FAN_PWM_DUTY2STATE(regval);
+
+	return 0;
+}
+
+static int mlxreg_fan_set_cur_state(struct thermal_cooling_device *cdev,
+				    unsigned long state)
+
+{
+	struct mlxreg_fan_pwm *pwm = cdev->devdata;
+	struct mlxreg_fan *fan = pwm->fan;
+	int err;
+
+	if (state > MLXREG_FAN_MAX_STATE)
+		return -EINVAL;
+
+	/* Save thermal state. */
+	pwm->last_thermal_state = state;
+
+	state = max_t(unsigned long, state, pwm->last_hwmon_state);
+	err = regmap_write(fan->regmap, pwm->reg,
+			   MLXREG_FAN_PWM_STATE2DUTY(state));
+	if (err) {
+		dev_err(fan->dev, "Failed to write PWM duty\n");
+		return err;
+	}
+	return 0;
+}
+
+static const struct thermal_cooling_device_ops mlxreg_fan_cooling_ops = {
+	.get_max_state	= mlxreg_fan_get_max_state,
+	.get_cur_state	= mlxreg_fan_get_cur_state,
+	.set_cur_state	= mlxreg_fan_set_cur_state,
+};
+
+static int mlxreg_fan_connect_verify(struct mlxreg_fan *fan,
+				     struct mlxreg_core_data *data)
+{
+	u32 regval;
+	int err;
+
+	err = regmap_read(fan->regmap, data->capability, &regval);
+	if (err) {
+		dev_err(fan->dev, "Failed to query capability register 0x%08x\n",
+			data->capability);
+		return err;
+	}
+
+	return !!(regval & data->bit);
+}
+
+static int mlxreg_pwm_connect_verify(struct mlxreg_fan *fan,
+				     struct mlxreg_core_data *data)
+{
+	u32 regval;
+	int err;
+
+	err = regmap_read(fan->regmap, data->reg, &regval);
+	if (err) {
+		dev_err(fan->dev, "Failed to query pwm register 0x%08x\n",
+			data->reg);
+		return err;
+	}
+
+	return regval != MLXREG_FAN_PWM_NOT_CONNECTED;
+}
+
+static int mlxreg_fan_speed_divider_get(struct mlxreg_fan *fan,
+					struct mlxreg_core_data *data)
+{
+	u32 regval;
+	int err;
+
+	err = regmap_read(fan->regmap, data->capability, &regval);
+	if (err) {
+		dev_err(fan->dev, "Failed to query capability register 0x%08x\n",
+			data->capability);
+		return err;
+	}
+
+	/*
+	 * Set divider value according to the capability register, in case it
+	 * contains valid value. Otherwise use default value. The purpose of
+	 * this validation is to protect against the old hardware, in which
+	 * this register can return zero.
+	 */
+	if (regval > 0 && regval <= MLXREG_FAN_TACHO_DIV_SCALE_MAX)
+		fan->divider = regval * MLXREG_FAN_TACHO_DIV_MIN;
+
+	return 0;
+}
+
+static int mlxreg_fan_config(struct mlxreg_fan *fan,
+			     struct mlxreg_core_platform_data *pdata)
+{
+	int tacho_num = 0, tacho_avail = 0, pwm_num = 0, i;
+	struct mlxreg_core_data *data = pdata->data;
+	bool configured = false;
+	int err;
+
+	fan->samples = MLXREG_FAN_TACHO_SAMPLES_PER_PULSE_DEF;
+	fan->divider = MLXREG_FAN_TACHO_DIV_DEF;
+	for (i = 0; i < pdata->counter; i++, data++) {
+		if (strnstr(data->label, "tacho", sizeof(data->label))) {
+			if (tacho_num == MLXREG_FAN_MAX_TACHO) {
+				dev_err(fan->dev, "too many tacho entries: %s\n",
+					data->label);
+				return -EINVAL;
+			}
+
+			if (data->capability) {
+				err = mlxreg_fan_connect_verify(fan, data);
+				if (err < 0)
+					return err;
+				else if (!err) {
+					tacho_num++;
+					continue;
+				}
+			}
+
+			fan->tacho[tacho_num].reg = data->reg;
+			fan->tacho[tacho_num].mask = data->mask;
+			fan->tacho[tacho_num].prsnt = data->reg_prsnt;
+			fan->tacho[tacho_num++].connected = true;
+			tacho_avail++;
+		} else if (strnstr(data->label, "pwm", sizeof(data->label))) {
+			if (pwm_num == MLXREG_FAN_MAX_TACHO) {
+				dev_err(fan->dev, "too many pwm entries: %s\n",
+					data->label);
+				return -EINVAL;
+			}
+
+			/* Validate if more then one PWM is connected. */
+			if (pwm_num) {
+				err = mlxreg_pwm_connect_verify(fan, data);
+				if (err < 0)
+					return err;
+				else if (!err)
+					continue;
+			}
+
+			fan->pwm[pwm_num].reg = data->reg;
+			fan->pwm[pwm_num].connected = true;
+			pwm_num++;
+		} else if (strnstr(data->label, "conf", sizeof(data->label))) {
+			if (configured) {
+				dev_err(fan->dev, "duplicate conf entry: %s\n",
+					data->label);
+				return -EINVAL;
+			}
+			/* Validate that conf parameters are not zeros. */
+			if (!data->mask && !data->bit && !data->capability) {
+				dev_err(fan->dev, "invalid conf entry params: %s\n",
+					data->label);
+				return -EINVAL;
+			}
+			if (data->capability) {
+				err = mlxreg_fan_speed_divider_get(fan, data);
+				if (err)
+					return err;
+			} else {
+				if (data->mask)
+					fan->samples = data->mask;
+				if (data->bit)
+					fan->divider = data->bit;
+			}
+			configured = true;
+		} else {
+			dev_err(fan->dev, "invalid label: %s\n", data->label);
+			return -EINVAL;
+		}
+	}
+
+	if (pdata->capability) {
+		int drwr_avail;
+		u32 regval;
+
+		/* Obtain the number of FAN drawers, supported by system. */
+		err = regmap_read(fan->regmap, pdata->capability, &regval);
+		if (err) {
+			dev_err(fan->dev, "Failed to query capability register 0x%08x\n",
+				pdata->capability);
+			return err;
+		}
+
+		drwr_avail = hweight32(regval);
+		if (!tacho_avail || !drwr_avail || tacho_avail < drwr_avail) {
+			dev_err(fan->dev, "Configuration is invalid: drawers num %d tachos num %d\n",
+				drwr_avail, tacho_avail);
+			return -EINVAL;
+		}
+
+		/* Set the number of tachometers per one drawer. */
+		fan->tachos_per_drwr = tacho_avail / drwr_avail;
+	}
+
+	return 0;
+}
+
+static int mlxreg_fan_cooling_config(struct device *dev, struct mlxreg_fan *fan)
+{
+	int i;
+
+	for (i = 0; i < MLXREG_FAN_MAX_PWM; i++) {
+		struct mlxreg_fan_pwm *pwm = &fan->pwm[i];
+
+		if (!pwm->connected)
+			continue;
+		pwm->fan = fan;
+		pwm->cdev = devm_thermal_of_cooling_device_register(dev, NULL, mlxreg_fan_name[i],
+								    pwm, &mlxreg_fan_cooling_ops);
+		if (IS_ERR(pwm->cdev)) {
+			dev_err(dev, "Failed to register cooling device\n");
+			return PTR_ERR(pwm->cdev);
+		}
+
+		/* Set minimal PWM speed. */
+		pwm->last_hwmon_state = MLXREG_FAN_PWM_DUTY2STATE(MLXREG_FAN_MIN_DUTY);
+	}
+
+	return 0;
+}
+
+static int mlxreg_fan_probe(struct platform_device *pdev)
+{
+	struct mlxreg_core_platform_data *pdata;
+	struct device *dev = &pdev->dev;
+	struct mlxreg_fan *fan;
+	struct device *hwm;
+	int err;
+
+	pdata = dev_get_platdata(dev);
+	if (!pdata) {
+		dev_err(dev, "Failed to get platform data.\n");
+		return -EINVAL;
+	}
+
+	fan = devm_kzalloc(dev, sizeof(*fan), GFP_KERNEL);
+	if (!fan)
+		return -ENOMEM;
+
+	fan->dev = dev;
+	fan->regmap = pdata->regmap;
+
+	err = mlxreg_fan_config(fan, pdata);
+	if (err)
+		return err;
+
+	hwm = devm_hwmon_device_register_with_info(dev, "mlxreg_fan",
+						   fan,
+						   &mlxreg_fan_hwmon_chip_info,
+						   NULL);
+	if (IS_ERR(hwm)) {
+		dev_err(dev, "Failed to register hwmon device\n");
+		return PTR_ERR(hwm);
+	}
+
+	if (IS_REACHABLE(CONFIG_THERMAL))
+		err = mlxreg_fan_cooling_config(dev, fan);
+
+	return err;
+}
+
+static struct platform_driver mlxreg_fan_driver = {
+	.driver = {
+	    .name = "mlxreg-fan",
+	},
+	.probe = mlxreg_fan_probe,
+};
+
+module_platform_driver(mlxreg_fan_driver);
+
+MODULE_AUTHOR("Vadim Pasternak <vadimp@mellanox.com>");
+MODULE_DESCRIPTION("Mellanox FAN driver");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("platform:mlxreg-fan");