[PATCH v12] thermal: drivers: mediatek: Add the Low Voltage Thermal Sensor driver

Krzysztof Kozlowski krzysztof.kozlowski at linaro.org
Tue Jan 31 23:55:07 PST 2023


On 31/01/2023 16:38, bchihi at baylibre.com wrote:
> From: Balsam CHIHI <bchihi at baylibre.com>
> 
> The Low Voltage Thermal Sensor (LVTS) is a multiple sensors, multi
> controllers contained in a thermal domain.
> 
> A thermal domains can be the MCU or the AP.
> 
> Each thermal domains contain up to seven controllers, each thermal
> controller handle up to four thermal sensors.
> 
> The LVTS has two Finite State Machines (FSM), one to handle the
> functionin temperatures range like hot or cold temperature and another
> one to handle monitoring trip point. The FSM notifies via interrupts
> when a trip point is crossed.
> 

(...)

> +
> +struct lvts_domain {
> +	struct lvts_ctrl *lvts_ctrl;
> +	struct reset_control *reset;
> +	struct clk *clk;
> +	int num_lvts_ctrl;
> +	void __iomem *base;
> +	size_t calib_len;
> +	u8 *calib;
> +};
> +
> +#ifdef CONFIG_MTK_LVTS_THERMAL_DEBUGFS
> +
> +static struct dentry *root;

How do you handle two instances of driver?

> +
> +#define LVTS_DEBUG_FS_REGS(__reg)		\
> +{						\
> +	.name = __stringify(__reg),		\
> +	.offset = __reg(0),			\
> +}
> +

(...)

> +
> +static int lvts_set_trips(struct thermal_zone_device *tz, int low, int high)
> +{
> +	struct lvts_sensor *lvts_sensor = tz->devdata;
> +	void __iomem *base = lvts_sensor->base;
> +	u32 raw_low = lvts_temp_to_raw(low);
> +	u32 raw_high = lvts_temp_to_raw(high);
> +
> +	/*
> +	 * Hot to normal temperature threshold
> +	 *
> +	 * LVTS_H2NTHRE
> +	 *
> +	 * Bits:
> +	 *
> +	 * 14-0 : Raw temperature for threshold
> +	 */
> +	if (low != -INT_MAX) {
> +		dev_dbg(&tz->device, "Setting low limit temperature interrupt: %d\n", low);
> +		writel(raw_low, LVTS_H2NTHRE(base));
> +	}
> +
> +	/*
> +	 * Hot temperature threshold
> +	 *
> +	 * LVTS_HTHRE
> +	 *
> +	 * Bits:
> +	 *
> +	 * 14-0 : Raw temperature for threshold
> +	 */
> +	dev_dbg(&tz->device, "Setting high limit temperature interrupt: %d\n", high);
> +	writel(raw_high, LVTS_HTHRE(base));
> +
> +	return 0;
> +}
> +
> +static irqreturn_t lvts_ctrl_irq_handler(struct lvts_ctrl *lvts_ctrl)
> +{
> +	irqreturn_t iret = IRQ_NONE;
> +	u32 value, masks[] = {

Don't mix different types in one declaration. u32 and a pointer are
quite different types.

> +		LVTS_INT_SENSOR0,
> +		LVTS_INT_SENSOR1,
> +		LVTS_INT_SENSOR2,
> +		LVTS_INT_SENSOR3
> +	};
> +	int i;
> +
> +	/*
> +	 * Interrupt monitoring status
> +	 *
> +	 * LVTS_MONINTST
> +	 *
> +	 * Bits:
> +	 *
> +	 * 31 : Interrupt for stage 3
> +	 * 30 : Interrupt for stage 2
> +	 * 29 : Interrupt for state 1
> +	 * 28 : Interrupt using filter on sensor 3
> +	 *
> +	 * 27 : Interrupt using immediate on sensor 3
> +	 * 26 : Interrupt normal to hot on sensor 3
> +	 * 25 : Interrupt high offset on sensor 3
> +	 * 24 : Interrupt low offset on sensor 3
> +	 *
> +	 * 23 : Interrupt hot threshold on sensor 3
> +	 * 22 : Interrupt cold threshold on sensor 3
> +	 * 21 : Interrupt using filter on sensor 2
> +	 * 20 : Interrupt using filter on sensor 1
> +	 *
> +	 * 19 : Interrupt using filter on sensor 0
> +	 * 18 : Interrupt using immediate on sensor 2
> +	 * 17 : Interrupt using immediate on sensor 1
> +	 * 16 : Interrupt using immediate on sensor 0
> +	 *
> +	 * 15 : Interrupt device access timeout interrupt
> +	 * 14 : Interrupt normal to hot on sensor 2
> +	 * 13 : Interrupt high offset interrupt on sensor 2
> +	 * 12 : Interrupt low offset interrupt on sensor 2
> +	 *
> +	 * 11 : Interrupt hot threshold on sensor 2
> +	 * 10 : Interrupt cold threshold on sensor 2
> +	 *  9 : Interrupt normal to hot on sensor 1
> +	 *  8 : Interrupt high offset interrupt on sensor 1
> +	 *
> +	 *  7 : Interrupt low offset interrupt on sensor 1
> +	 *  6 : Interrupt hot threshold on sensor 1
> +	 *  5 : Interrupt cold threshold on sensor 1
> +	 *  4 : Interrupt normal to hot on sensor 0
> +	 *
> +	 *  3 : Interrupt high offset interrupt on sensor 0
> +	 *  2 : Interrupt low offset interrupt on sensor 0
> +	 *  1 : Interrupt hot threshold on sensor 0
> +	 *  0 : Interrupt cold threshold on sensor 0
> +	 *
> +	 * We are interested in the sensor(s) responsible of the
> +	 * interrupt event. We update the thermal framework with the
> +	 * thermal zone associated with the sensor. The framework will
> +	 * take care of the rest whatever the kind of interrupt, we
> +	 * are only interested in which sensor raised the interrupt.
> +	 *
> +	 * sensor 3 interrupt: 0001 1111 1100 0000 0000 0000 0000 0000
> +	 *                  => 0x1FC00000
> +	 * sensor 2 interrupt: 0000 0000 0010 0100 0111 1100 0000 0000
> +	 *                  => 0x00247C00
> +	 * sensor 1 interrupt: 0000 0000 0001 0001 0000 0011 1110 0000
> +	 *                  => 0X000881F0
> +	 * sensor 0 interrupt: 0000 0000 0000 1001 0000 0000 0001 1111
> +	 *                  => 0x0009001F
> +	 */
> +	value = readl(LVTS_MONINTSTS(lvts_ctrl->base));
> +
> +	/*
> +	 * Let's figure out which sensors raised the interrupt
> +	 *
> +	 * NOTE: the masks array must be ordered with the index
> +	 * corresponding to the sensor id eg. index=0, mask for
> +	 * sensor0.
> +	 */
> +	for (i = 0; i < ARRAY_SIZE(masks); i++) {
> +
> +		if (!(value & masks[i]))
> +			continue;
> +
> +		thermal_zone_device_update(lvts_ctrl->sensors[i].tz,
> +					   THERMAL_TRIP_VIOLATED);
> +		iret = IRQ_HANDLED;
> +	}
> +
> +	/*
> +	 * Write back to clear the interrupt status (W1C)
> +	 */
> +	writel(value, LVTS_MONINTSTS(lvts_ctrl->base));
> +
> +	return iret;
> +}
> +
> +/*
> + * Temperature interrupt handler. Even if the driver supports more
> + * interrupt modes, we use the interrupt when the temperature crosses
> + * the hot threshold the way up and the way down (modulo the
> + * hysteresis).
> + *
> + * Each thermal domain has a couple of interrupts, one for hardware
> + * reset and another one for all the thermal events happening on the
> + * different sensors.
> + *
> + * The interrupt is configured for thermal events when crossing the
> + * hot temperature limit. At each interrupt, we check in every
> + * controller if there is an interrupt pending.
> + */
> +static irqreturn_t lvts_irq_handler(int irq, void *data)
> +{
> +	struct lvts_domain *lvts_td = data;
> +	irqreturn_t aux, iret = IRQ_NONE;
> +	int i;
> +
> +	for (i = 0; i < lvts_td->num_lvts_ctrl; i++) {
> +
> +		aux = lvts_ctrl_irq_handler(lvts_td->lvts_ctrl);
> +		if (aux != IRQ_HANDLED)
> +			continue;
> +
> +		iret = IRQ_HANDLED;
> +	}
> +
> +	return iret;
> +}
> +
> +static struct thermal_zone_device_ops lvts_ops = {
> +	.get_temp = lvts_get_temp,
> +	.set_trips = lvts_set_trips,
> +};
> +
> +static int __init lvts_sensor_init(struct device *dev,
> +				   struct lvts_ctrl *lvts_ctrl,
> +				   struct lvts_ctrl_data *lvts_ctrl_data)
> +{
> +	struct lvts_sensor *lvts_sensor = lvts_ctrl->sensors;
> +	void __iomem *msr_regs[] = {
> +		LVTS_MSR0(lvts_ctrl->base),
> +		LVTS_MSR1(lvts_ctrl->base),
> +		LVTS_MSR2(lvts_ctrl->base),
> +		LVTS_MSR3(lvts_ctrl->base)
> +	};
> +
> +	void __iomem *imm_regs[] = {
> +		LVTS_IMMD0(lvts_ctrl->base),
> +		LVTS_IMMD1(lvts_ctrl->base),
> +		LVTS_IMMD2(lvts_ctrl->base),
> +		LVTS_IMMD3(lvts_ctrl->base)
> +	};
> +
> +	int i;
> +
> +	for (i = 0; i < lvts_ctrl_data->num_lvts_sensor; i++) {
> +
> +		int dt_id = lvts_ctrl_data->lvts_sensor[i].dt_id;
> +
> +		/*
> +		 * At this point, we don't know which id matches which
> +		 * sensor. Let's set arbitrally the id from the index.
> +		 */
> +		lvts_sensor[i].id = i;
> +
> +		/*
> +		 * The thermal zone registration will set the trip
> +		 * point interrupt in the thermal controller
> +		 * register. But this one will be reset in the
> +		 * initialization after. So we need to post pone the
> +		 * thermal zone creation after the controller is
> +		 * setup. For this reason, we store the device tree
> +		 * node id from the data in the sensor structure
> +		 */
> +		lvts_sensor[i].dt_id = dt_id;
> +
> +		/*
> +		 * We assign the base address of the thermal
> +		 * controller as a back pointer. So it will be
> +		 * accessible from the different thermal framework ops
> +		 * as we pass the lvts_sensor pointer as thermal zone
> +		 * private data.
> +		 */
> +		lvts_sensor[i].base = lvts_ctrl->base;
> +
> +		/*
> +		 * Each sensor has its own register address to read from.
> +		 */
> +		lvts_sensor[i].msr = lvts_ctrl_data->mode == LVTS_MSR_IMMEDIATE_MODE ?
> +			imm_regs[i] : msr_regs[i];
> +	};
> +
> +	lvts_ctrl->num_lvts_sensor = lvts_ctrl_data->num_lvts_sensor;
> +
> +	return 0;
> +}
> +
> +/*
> + * The efuse blob values follows the sensor enumeration per thermal
> + * controller. The decoding of the stream is as follow:
> + *
> + *                        <--?-> <----big0 ???---> <-sensor0-> <-0->
> + *                        ------------------------------------------
> + * index in the stream: : | 0x0 | 0x1 | 0x2 | 0x3 | 0x4 | 0x5 | 0x6 |
> + *                        ------------------------------------------
> + *
> + *                        <--sensor1--><-0-> <----big1 ???---> <-sen
> + *                        ------------------------------------------
> + *                        | 0x7 | 0x8 | 0x9 | 0xA | 0xB | OxC | OxD |
> + *                        ------------------------------------------
> + *
> + *                        sor0-> <-0-> <-sensor1-> <-0-> ..........
> + *                        ------------------------------------------
> + *                        | 0x7 | 0x8 | 0x9 | 0xA | 0xB | OxC | OxD |
> + *                        ------------------------------------------
> + *
> + * And so on ...
> + *
> + * The data description gives the offset of the calibration data in
> + * this bytes stream for each sensor.
> + *
> + * Each thermal controller can handle up to 4 sensors max, we don't
> + * care if there are less as the array of calibration is sized to 4
> + * anyway. The unused sensor slot will be zeroed.
> + */
> +static int __init lvts_calibration_init(struct device *dev,
> +					struct lvts_ctrl *lvts_ctrl,
> +					struct lvts_ctrl_data *lvts_ctrl_data,
> +					u8 *efuse_calibration)
> +{
> +	int i;
> +
> +	for (i = 0; i < lvts_ctrl_data->num_lvts_sensor; i++)
> +		memcpy(&lvts_ctrl->calibration[i],
> +		       efuse_calibration + lvts_ctrl_data->cal_offset[i], 2);
> +
> +	return 0;
> +}
> +
> +/*
> + * The efuse bytes stream can be split into different chunk of
> + * nvmems. This function reads and concatenate those into a single
> + * buffer so it can be read sequentially when initializing the
> + * calibration data.
> + */
> +static int lvts_calibration_read(struct device *dev, struct lvts_domain *lvts_td,
> +				 struct lvts_data *lvts_data)
> +{
> +	struct device_node *np = dev_of_node(dev);
> +	struct nvmem_cell *cell;
> +	struct property *prop;
> +	const char *cell_name;
> +
> +	of_property_for_each_string(np, "nvmem-cell-names", prop, cell_name) {
> +		size_t len;
> +		u8 *efuse;
> +
> +		cell = of_nvmem_cell_get(np, cell_name);
> +		if (IS_ERR(cell)) {
> +			dev_dbg(dev, "Failed to get cell '%s'\n", cell_name);

Is this an error? If so, why debug? dbg is not for errors.

> +			return PTR_ERR(cell);
> +		}
> +
> +		efuse = nvmem_cell_read(cell, &len);
> +
> +		nvmem_cell_put(cell);
> +
> +		if (IS_ERR(efuse)) {
> +			dev_dbg(dev, "Failed to read cell '%s'\n", cell_name);
> +			return PTR_ERR(efuse);
> +		}
> +
> +		lvts_td->calib = devm_krealloc(dev, lvts_td->calib,
> +					       lvts_td->calib_len + len, GFP_KERNEL);
> +		if (!lvts_td->calib)
> +			return -ENOMEM;
> +
> +		memcpy(lvts_td->calib + lvts_td->calib_len, efuse, len);
> +
> +		lvts_td->calib_len += len;
> +
> +		kfree(efuse);
> +	}
> +
> +	return 0;
> +}
> +
> +static int __init lvts_golden_temp_init(struct device *dev, u32 *value)

You did not test it, right? Build with section mismatch analysis...

> +{
> +	u32 gt;
> +
> +	gt = (*value) >> 24;
> +
> +	if (gt && gt < LVTS_GOLDEN_TEMP_MAX)
> +		golden_temp = gt;
> +
> +	coeff_b = golden_temp * 500 + LVTS_COEFF_B;
> +
> +	return 0;
> +}
> +
> +static int __init lvts_ctrl_init(struct device *dev,

Same problem.

> +				 struct lvts_domain *lvts_td,
> +				 struct lvts_data *lvts_data)
> +{
> +	size_t size = sizeof(*lvts_td->lvts_ctrl) * lvts_data->num_lvts_ctrl;
> +	struct lvts_ctrl *lvts_ctrl;
> +	int i, ret;
> +

> +
> +static inline int lvts_ctrl_enable(struct device *dev, struct lvts_ctrl *lvts_ctrl)
> +{
> +	return lvts_ctrl_set_enable(lvts_ctrl, 1);

Drop the wrapper, it's useless. true or false for enable are quite obvious.

> +}
> +
> +static inline int lvts_ctrl_disable(struct device *dev, struct lvts_ctrl *lvts_ctrl)
> +{
> +	return lvts_ctrl_set_enable(lvts_ctrl, 0);

Drop the wrapper.

> +}
> +
> +static int lvts_ctrl_connect(struct device *dev, struct lvts_ctrl *lvts_ctrl)
> +{
> +	u32 id, cmds[] = { 0xC103FFFF, 0xC502FF55 };
> +
> +	lvts_write_config(lvts_ctrl, cmds, ARRAY_SIZE(cmds));
> +
> +	/*
> +	 * LVTS_ID : Get ID and status of the thermal controller
> +	 *
> +	 * Bits:
> +	 *
> +	 * 0-5	: thermal controller id
> +	 *   7	: thermal controller connection is valid
> +	 */
> +	id = readl(LVTS_ID(lvts_ctrl->base));
> +	if (!(id & BIT(7)))
> +		return -EIO;
> +
> +	return 0;
> +}
> +
> +static int lvts_ctrl_initialize(struct device *dev, struct lvts_ctrl *lvts_ctrl)
> +{
> +	/*
> +	 * Write device mask: 0xC1030000
> +	 */
> +	u32 cmds[] = {
> +		0xC1030E01, 0xC1030CFC, 0xC1030A8C, 0xC103098D, 0xC10308F1,
> +		0xC10307A6, 0xC10306B8, 0xC1030500, 0xC1030420, 0xC1030300,
> +		0xC1030030, 0xC10300F6, 0xC1030050, 0xC1030060, 0xC10300AC,
> +		0xC10300FC, 0xC103009D, 0xC10300F1, 0xC10300E1
> +	};
> +
> +	lvts_write_config(lvts_ctrl, cmds, ARRAY_SIZE(cmds));
> +
> +	return 0;
> +}
> +
> +static int lvts_ctrl_calibrate(struct device *dev, struct lvts_ctrl *lvts_ctrl)
> +{
> +	int i;
> +	void __iomem *lvts_edata[] = {
> +		LVTS_EDATA00(lvts_ctrl->base),
> +		LVTS_EDATA01(lvts_ctrl->base),
> +		LVTS_EDATA02(lvts_ctrl->base),
> +		LVTS_EDATA03(lvts_ctrl->base)
> +	};
> +
> +	/*
> +	 * LVTS_EDATA0X : Efuse calibration reference value for sensor X
> +	 *
> +	 * Bits:
> +	 *
> +	 * 20-0 : Efuse value for normalization data
> +	 */
> +	for (i = 0; i < LVTS_SENSOR_MAX; i++)
> +		writel(lvts_ctrl->calibration[i], lvts_edata[i]);
> +
> +	return 0;
> +}
> +
> +static int lvts_ctrl_configure(struct device *dev, struct lvts_ctrl *lvts_ctrl)
> +{
> +	u32 value;
> +
> +	/*
> +	 * LVTS_TSSEL : Sensing point index numbering
> +	 *
> +	 * Bits:
> +	 *
> +	 * 31-24: ADC Sense 3
> +	 * 23-16: ADC Sense 2
> +	 * 15-8	: ADC Sense 1
> +	 * 7-0	: ADC Sense 0
> +	 */
> +	value = LVTS_TSSEL_CONF;
> +	writel(value, LVTS_TSSEL(lvts_ctrl->base));
> +
> +	/*
> +	 * LVTS_CALSCALE : ADC voltage round
> +	 */
> +	value = 0x300;
> +	value = LVTS_CALSCALE_CONF;
> +
> +	/*
> +	 * LVTS_MSRCTL0 : Sensor filtering strategy
> +	 *
> +	 * Filters:
> +	 *
> +	 * 000 : One sample
> +	 * 001 : Avg 2 samples
> +	 * 010 : 4 samples, drop min and max, avg 2 samples
> +	 * 011 : 6 samples, drop min and max, avg 4 samples
> +	 * 100 : 10 samples, drop min and max, avg 8 samples
> +	 * 101 : 18 samples, drop min and max, avg 16 samples
> +	 *
> +	 * Bits:
> +	 *
> +	 * 0-2  : Sensor0 filter
> +	 * 3-5  : Sensor1 filter
> +	 * 6-8  : Sensor2 filter
> +	 * 9-11 : Sensor3 filter
> +	 */
> +	value = LVTS_HW_FILTER << 9 |  LVTS_HW_FILTER << 6 |
> +			LVTS_HW_FILTER << 3 | LVTS_HW_FILTER;
> +	writel(value, LVTS_MSRCTL0(lvts_ctrl->base));
> +
> +	/*
> +	 * LVTS_MSRCTL1 : Measurement control
> +	 *
> +	 * Bits:
> +	 *
> +	 * 9: Ignore MSRCTL0 config and do immediate measurement on sensor3
> +	 * 6: Ignore MSRCTL0 config and do immediate measurement on sensor2
> +	 * 5: Ignore MSRCTL0 config and do immediate measurement on sensor1
> +	 * 4: Ignore MSRCTL0 config and do immediate measurement on sensor0
> +	 *
> +	 * That configuration will ignore the filtering and the delays
> +	 * introduced below in MONCTL1 and MONCTL2
> +	 */
> +	if (lvts_ctrl->mode == LVTS_MSR_IMMEDIATE_MODE) {
> +		value = BIT(9) | BIT(6) | BIT(5) | BIT(4);
> +		writel(value, LVTS_MSRCTL1(lvts_ctrl->base));
> +	}
> +
> +	/*
> +	 * LVTS_MONCTL1 : Period unit and group interval configuration
> +	 *
> +	 * The clock source of LVTS thermal controller is 26MHz.
> +	 *
> +	 * The period unit is a time base for all the interval delays
> +	 * specified in the registers. By default we use 12. The time
> +	 * conversion is done by multiplying by 256 and 1/26.10^6
> +	 *
> +	 * An interval delay multiplied by the period unit gives the
> +	 * duration in seconds.
> +	 *
> +	 * - Filter interval delay is a delay between two samples of
> +	 * the same sensor.
> +	 *
> +	 * - Sensor interval delay is a delay between two samples of
> +	 * different sensors.
> +	 *
> +	 * - Group interval delay is a delay between different rounds.
> +	 *
> +	 * For example:
> +	 *     If Period unit = C, filter delay = 1, sensor delay = 2, group delay = 1,
> +	 *     and two sensors, TS1 and TS2, are in a LVTS thermal controller
> +	 *     and then
> +	 *     Period unit time = C * 1/26M * 256 = 12 * 38.46ns * 256 = 118.149us
> +	 *     Filter interval delay = 1 * Period unit = 118.149us
> +	 *     Sensor interval delay = 2 * Period unit = 236.298us
> +	 *     Group interval delay = 1 * Period unit = 118.149us
> +	 *
> +	 *     TS1    TS1 ... TS1    TS2    TS2 ... TS2    TS1...
> +	 *        <--> Filter interval delay
> +	 *                       <--> Sensor interval delay
> +	 *                                             <--> Group interval delay
> +	 * Bits:
> +	 *      29 - 20 : Group interval
> +	 *      16 - 13 : Send a single interrupt when crossing the hot threshold (1)
> +	 *                or an interrupt everytime the hot threshold is crossed (0)
> +	 *       9 - 0  : Period unit
> +	 *
> +	 */
> +	value = LVTS_GROUP_INTERVAL << 20 | LVTS_PERIOD_UNIT;
> +	writel(value, LVTS_MONCTL1(lvts_ctrl->base));
> +
> +	/*
> +	 * LVTS_MONCTL2 : Filtering and sensor interval
> +	 *
> +	 * Bits:
> +	 *
> +	 *      25-16 : Interval unit in PERIOD_UNIT between sample on
> +	 *              the same sensor, filter interval
> +	 *       9-0  : Interval unit in PERIOD_UNIT between each sensor
> +	 *
> +	 */
> +	value = LVTS_FILTER_INTERVAL << 16 | LVTS_SENSOR_INTERVAL;
> +	writel(value, LVTS_MONCTL2(lvts_ctrl->base));
> +
> +	return lvts_irq_init(lvts_ctrl);
> +}
> +
> +static int lvts_ctrl_start(struct device *dev, struct lvts_ctrl *lvts_ctrl)
> +{
> +	struct lvts_sensor *lvts_sensors = lvts_ctrl->sensors;
> +	struct thermal_zone_device *tz;
> +	u32 sensor_map = 0;
> +	int i;
> +
> +	for (i = 0; i < lvts_ctrl->num_lvts_sensor; i++) {
> +
> +		int dt_id = lvts_sensors[i].dt_id;
> +
> +		tz = devm_thermal_of_zone_register(dev, dt_id, &lvts_sensors[i],
> +						   &lvts_ops);
> +		if (IS_ERR(tz)) {
> +			/*
> +			 * This thermal zone is not described in the
> +			 * device tree. It is not an error from the
> +			 * thermal OF code POV, we just continue.
> +			 */
> +			if (PTR_ERR(tz) == -ENODEV)
> +				continue;
> +
> +			return PTR_ERR(tz);
> +		}
> +
> +		/*
> +		 * The thermal zone pointer will be needed in the
> +		 * interrupt handler, we store it in the sensor
> +		 * structure. The thermal domain structure will be
> +		 * passed to the interrupt handler private data as the
> +		 * interrupt is shared for all the controller
> +		 * belonging to the thermal domain.
> +		 */
> +		lvts_sensors[i].tz = tz;
> +
> +		/*
> +		 * This sensor was correctly associated with a thermal
> +		 * zone, let's set the corresponding bit in the sensor
> +		 * map, so we can enable the temperature monitoring in
> +		 * the hardware thermal controller.
> +		 */
> +		sensor_map |= BIT(i);
> +	}
> +
> +	/*
> +	 * Bits:
> +	 *      9: Single point access flow
> +	 *    0-3: Enable sensing point 0-3
> +	 *
> +	 * The initialization of the thermal zones give us
> +	 * which sensor point to enable. If any thermal zone
> +	 * was not described in the device tree, it won't be
> +	 * enabled here in the sensor map.
> +	 */
> +	writel(sensor_map | BIT(9), LVTS_MONCTL0(lvts_ctrl->base));
> +
> +	return 0;
> +}
> +
> +static int lvts_domain_init(struct device *dev, struct lvts_domain *lvts_td,
> +			    struct lvts_data *lvts_data)
> +{
> +	struct lvts_ctrl *lvts_ctrl;
> +	int i, ret;
> +
> +	ret = lvts_ctrl_init(dev, lvts_td, lvts_data);
> +	if (ret)
> +		return ret;
> +
> +	ret = lvts_domain_reset(dev, lvts_td->reset);
> +	if (ret) {
> +		dev_dbg(dev, "Failed to reset domain");
> +		return ret;
> +	}
> +
> +	for (i = 0; i < lvts_td->num_lvts_ctrl; i++) {
> +
> +		lvts_ctrl = &lvts_td->lvts_ctrl[i];
> +
> +		/*
> +		 * Initialization steps:
> +		 *
> +		 * - Enable the clock
> +		 * - Connect to the LVTS
> +		 * - Initialize the LVTS
> +		 * - Prepare the calibration data
> +		 * - Select monitored sensors
> +		 * [ Configure sampling ]
> +		 * [ Configure the interrupt ]
> +		 * - Start measurement
> +		 */
> +		ret = lvts_ctrl_enable(dev, lvts_ctrl);
> +		if (ret) {
> +			dev_dbg(dev, "Failed to enable LVTS clock");
> +			return ret;
> +		}
> +
> +		ret = lvts_ctrl_connect(dev, lvts_ctrl);
> +		if (ret) {
> +			dev_dbg(dev, "Failed to connect to LVTS controller");
> +			return ret;
> +		}
> +
> +		ret = lvts_ctrl_initialize(dev, lvts_ctrl);
> +		if (ret) {
> +			dev_dbg(dev, "Failed to initialize controller");
> +			return ret;
> +		}
> +
> +		ret = lvts_ctrl_calibrate(dev, lvts_ctrl);
> +		if (ret) {
> +			dev_dbg(dev, "Failed to calibrate controller");
> +			return ret;
> +		}
> +
> +		ret = lvts_ctrl_configure(dev, lvts_ctrl);
> +		if (ret) {
> +			dev_dbg(dev, "Failed to configure controller");
> +			return ret;
> +		}
> +
> +		ret = lvts_ctrl_start(dev, lvts_ctrl);
> +		if (ret) {
> +			dev_dbg(dev, "Failed to start controller");
> +			return ret;
> +		}
> +	}
> +
> +	return lvts_debugfs_init(dev, lvts_td);
> +}
> +
> +static int lvts_probe(struct platform_device *pdev)
> +{
> +	struct lvts_data *lvts_data;
> +	struct lvts_domain *lvts_td;
> +	struct device *dev = &pdev->dev;
> +	struct resource *res;
> +	int irq, ret;
> +
> +	lvts_td = devm_kzalloc(dev, sizeof(*lvts_td), GFP_KERNEL);
> +	if (!lvts_td)
> +		return -ENOMEM;
> +
> +	lvts_data = (struct lvts_data *)of_device_get_match_data(dev);

Why do you need case?

> +	if (!lvts_data) {
> +		dev_dbg(dev, "No platforme 

Drop. How is it even possible?

> +		return -ENODATA;
> +	};
> +
> +	lvts_td->clk = devm_clk_get_enabled(dev, NULL);
> +	if (IS_ERR(lvts_td->clk)) {
> +		dev_dbg(dev, "Failed to retrieve clock\n");

Drop all debug statements. Either this is an error (so return
dev_err_probe) or core handles messages.

> +		return PTR_ERR(lvts_td->clk);
> +	}
> +
> +	res = platform_get_mem_or_io(pdev, 0);
> +	if (!res) {
> +		dev_dbg(dev, "No IO resource\n");

Ditto

> +		return -ENXIO;
> +	}
> +
> +	lvts_td->base = devm_ioremap_resource(dev, res);

Why not using single wrapper for this?

> +	if (IS_ERR(lvts_td->base)) {
> +		dev_dbg(dev, "Failed to map io resource\n");

Ditto

> +		return PTR_ERR(lvts_td->base);
> +	}
> +
> +	lvts_td->reset = devm_reset_control_get_by_index(dev, 0);
> +	if (IS_ERR(lvts_td->reset)) {
> +		dev_dbg(dev, "Failed to get reset control\n");

Ditto

> +		return PTR_ERR(lvts_td->reset);
> +	}
> +
> +	irq = platform_get_irq(pdev, 0);
> +	if (irq < 0) {
> +		dev_dbg(dev, "No irq resource\n");

Ditto

> +		return irq;
> +	}
> +
> +	ret = lvts_domain_init(dev, lvts_td, lvts_data);
> +	if (ret) {
> +		dev_dbg(dev, "Failed to initialize the lvts domain\n");

Why this is debug?

> +		return ret;
> +	}
> +
> +	/*
> +	 * At this point the LVTS is initialized and enabled. We can
> +	 * safely enable the interrupt.
> +	 */
> +	ret = devm_request_threaded_irq(dev, irq, NULL, lvts_irq_handler,
> +					IRQF_ONESHOT, dev_name(dev), lvts_td);
> +	if (ret) {
> +		dev_dbg(dev, "Failed to request interrupt\n");

Ditto

> +		return ret;
> +	}
> +
> +	platform_set_drvdata(pdev, lvts_td);
> +
> +	return 0;
> +}
> +
> +static int lvts_remove(struct platform_device *pdev)
> +{
> +	struct lvts_domain *lvts_td;
> +	struct device *dev = &pdev->dev;
> +	int i;
> +
> +	lvts_td = platform_get_drvdata(pdev);
> +
> +	for (i = 0; i < lvts_td->num_lvts_ctrl; i++)
> +		lvts_ctrl_disable(dev, &lvts_td->lvts_ctrl[i]);
> +
> +	lvts_debugfs_exit();
> +
> +	return 0;
> +}
> +
> +static struct lvts_ctrl_data mt8195_lvts_data_ctrl[] = {

Why this cannot be const?

> +	{
> +		.cal_offset = { 0x4, 0x7 },
> +		.lvts_sensor = {
> +			{ .dt_id = MT8195_MCU_BIG_CPU0 },
> +			{ .dt_id = MT8195_MCU_BIG_CPU1 }
> +		},
> +		.num_lvts_sensor = 2,
> +		.offset = 0x0,
> +		.hw_tshut_temp = LVTS_HW_SHUTDOWN_MT8195,
> +	},
> +

Drop blank line

> +	{

Best regards,
Krzysztof




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