Orange Pi5 kernel

// SPDX-License-Identifier: GPL-2.0
/*
 * Intel MID platform thermal driver
 *
 * Copyright (C) 2011 Intel Corporation
 *
 * Author: Durgadoss R <durgadoss.r@intel.com>
 */
 
#define pr_fmt(fmt) "intel_mid_thermal: " fmt
 
#include <linux/device.h>
#include <linux/err.h>
#include <linux/mfd/intel_msic.h>
#include <linux/module.h>
#include <linux/param.h>
#include <linux/platform_device.h>
#include <linux/pm.h>
#include <linux/slab.h>
#include <linux/thermal.h>
 
/* Number of thermal sensors */
#define MSIC_THERMAL_SENSORS	4
 
/* ADC1 - thermal registers */
#define MSIC_ADC_ENBL		0x10
#define MSIC_ADC_START		0x08
 
#define MSIC_ADCTHERM_ENBL	0x04
#define MSIC_ADCRRDATA_ENBL	0x05
#define MSIC_CHANL_MASK_VAL	0x0F
 
#define MSIC_STOPBIT_MASK	16
#define MSIC_ADCTHERM_MASK	4
/* Number of ADC channels */
#define ADC_CHANLS_MAX		15
#define ADC_LOOP_MAX		(ADC_CHANLS_MAX - MSIC_THERMAL_SENSORS)
 
/* ADC channel code values */
#define SKIN_SENSOR0_CODE	0x08
#define SKIN_SENSOR1_CODE	0x09
#define SYS_SENSOR_CODE		0x0A
#define MSIC_DIE_SENSOR_CODE	0x03
 
#define SKIN_THERM_SENSOR0	0
#define SKIN_THERM_SENSOR1	1
#define SYS_THERM_SENSOR2	2
#define MSIC_DIE_THERM_SENSOR3	3
 
/* ADC code range */
#define ADC_MAX			977
#define ADC_MIN			162
#define ADC_VAL0C		887
#define ADC_VAL20C		720
#define ADC_VAL40C		508
#define ADC_VAL60C		315
 
/* ADC base addresses */
#define ADC_CHNL_START_ADDR	INTEL_MSIC_ADC1ADDR0	/* increments by 1 */
#define ADC_DATA_START_ADDR	INTEL_MSIC_ADC1SNS0H	/* increments by 2 */
 
/* MSIC die attributes */
#define MSIC_DIE_ADC_MIN	488
#define MSIC_DIE_ADC_MAX	1004
 
/* This holds the address of the first free ADC channel,
 * among the 15 channels
 */
static int channel_index;
 
struct platform_info {
<------>struct platform_device *pdev;
<------>struct thermal_zone_device *tzd[MSIC_THERMAL_SENSORS];
};
 
struct thermal_device_info {
<------>unsigned int chnl_addr;
<------>int direct;
<------>/* This holds the current temperature in millidegree celsius */
<------>long curr_temp;
};
 
/**
 * to_msic_die_temp - converts adc_val to msic_die temperature
 * @adc_val: ADC value to be converted
 *
 * Can sleep
 */
static int to_msic_die_temp(uint16_t adc_val)
{
<------>return (368 * (adc_val) / 1000) - 220;
}
 
/**
 * is_valid_adc - checks whether the adc code is within the defined range
 * @min: minimum value for the sensor
 * @max: maximum value for the sensor
 *
 * Can sleep
 */
static int is_valid_adc(uint16_t adc_val, uint16_t min, uint16_t max)
{
<------>return (adc_val >= min) && (adc_val <= max);
}
 
/**
 * adc_to_temp - converts the ADC code to temperature in C
 * @direct: true if ths channel is direct index
 * @adc_val: the adc_val that needs to be converted
 * @tp: temperature return value
 *
 * Linear approximation is used to covert the skin adc value into temperature.
 * This technique is used to avoid very long look-up table to get
 * the appropriate temp value from ADC value.
 * The adc code vs sensor temp curve is split into five parts
 * to achieve very close approximate temp value with less than
 * 0.5C error
 */
static int adc_to_temp(int direct, uint16_t adc_val, int *tp)
{
<------>int temp;
 
<------>/* Direct conversion for die temperature */
<------>if (direct) {
<------><------>if (is_valid_adc(adc_val, MSIC_DIE_ADC_MIN, MSIC_DIE_ADC_MAX)) {
<------><------><------>*tp = to_msic_die_temp(adc_val) * 1000;
<------><------><------>return 0;
<------><------>}
<------><------>return -ERANGE;
<------>}
 
<------>if (!is_valid_adc(adc_val, ADC_MIN, ADC_MAX))
<------><------>return -ERANGE;
 
<------>/* Linear approximation for skin temperature */
<------>if (adc_val > ADC_VAL0C)
<------><------>temp = 177 - (adc_val/5);
<------>else if ((adc_val <= ADC_VAL0C) && (adc_val > ADC_VAL20C))
<------><------>temp = 111 - (adc_val/8);
<------>else if ((adc_val <= ADC_VAL20C) && (adc_val > ADC_VAL40C))
<------><------>temp = 92 - (adc_val/10);
<------>else if ((adc_val <= ADC_VAL40C) && (adc_val > ADC_VAL60C))
<------><------>temp = 91 - (adc_val/10);
<------>else
<------><------>temp = 112 - (adc_val/6);
 
<------>/* Convert temperature in celsius to milli degree celsius */
<------>*tp = temp * 1000;
<------>return 0;
}
 
/**
 * mid_read_temp - read sensors for temperature
 * @temp: holds the current temperature for the sensor after reading
 *
 * reads the adc_code from the channel and converts it to real
 * temperature. The converted value is stored in temp.
 *
 * Can sleep
 */
static int mid_read_temp(struct thermal_zone_device *tzd, int *temp)
{
<------>struct thermal_device_info *td_info = tzd->devdata;
<------>uint16_t adc_val, addr;
<------>uint8_t data = 0;
<------>int ret;
<------>int curr_temp;
 
<------>addr = td_info->chnl_addr;
 
<------>/* Enable the msic for conversion before reading */
<------>ret = intel_msic_reg_write(INTEL_MSIC_ADC1CNTL3, MSIC_ADCRRDATA_ENBL);
<------>if (ret)
<------><------>return ret;
 
<------>/* Re-toggle the RRDATARD bit (temporary workaround) */
<------>ret = intel_msic_reg_write(INTEL_MSIC_ADC1CNTL3, MSIC_ADCTHERM_ENBL);
<------>if (ret)
<------><------>return ret;
 
<------>/* Read the higher bits of data */
<------>ret = intel_msic_reg_read(addr, &data);
<------>if (ret)
<------><------>return ret;
 
<------>/* Shift bits to accommodate the lower two data bits */
<------>adc_val = (data << 2);
<------>addr++;
 
<------>ret = intel_msic_reg_read(addr, &data);/* Read lower bits */
<------>if (ret)
<------><------>return ret;
 
<------>/* Adding lower two bits to the higher bits */
<------>data &= 03;
<------>adc_val += data;
 
<------>/* Convert ADC value to temperature */
<------>ret = adc_to_temp(td_info->direct, adc_val, &curr_temp);
<------>if (ret == 0)
<------><------>*temp = td_info->curr_temp = curr_temp;
<------>return ret;
}
 
/**
 * configure_adc - enables/disables the ADC for conversion
 * @val: zero: disables the ADC non-zero:enables the ADC
 *
 * Enable/Disable the ADC depending on the argument
 *
 * Can sleep
 */
static int configure_adc(int val)
{
<------>int ret;
<------>uint8_t data;
 
<------>ret = intel_msic_reg_read(INTEL_MSIC_ADC1CNTL1, &data);
<------>if (ret)
<------><------>return ret;
 
<------>if (val) {
<------><------>/* Enable and start the ADC */
<------><------>data |= (MSIC_ADC_ENBL | MSIC_ADC_START);
<------>} else {
<------><------>/* Just stop the ADC */
<------><------>data &= (~MSIC_ADC_START);
<------>}
<------>return intel_msic_reg_write(INTEL_MSIC_ADC1CNTL1, data);
}
 
/**
 * set_up_therm_channel - enable thermal channel for conversion
 * @base_addr: index of free msic ADC channel
 *
 * Enable all the three channels for conversion
 *
 * Can sleep
 */
static int set_up_therm_channel(u16 base_addr)
{
<------>int ret;
 
<------>/* Enable all the sensor channels */
<------>ret = intel_msic_reg_write(base_addr, SKIN_SENSOR0_CODE);
<------>if (ret)
<------><------>return ret;
 
<------>ret = intel_msic_reg_write(base_addr + 1, SKIN_SENSOR1_CODE);
<------>if (ret)
<------><------>return ret;
 
<------>ret = intel_msic_reg_write(base_addr + 2, SYS_SENSOR_CODE);
<------>if (ret)
<------><------>return ret;
 
<------>/* Since this is the last channel, set the stop bit
<------> * to 1 by ORing the DIE_SENSOR_CODE with 0x10 */
<------>ret = intel_msic_reg_write(base_addr + 3,
<------><------><------>(MSIC_DIE_SENSOR_CODE | 0x10));
<------>if (ret)
<------><------>return ret;
 
<------>/* Enable ADC and start it */
<------>return configure_adc(1);
}
 
/**
 * reset_stopbit - sets the stop bit to 0 on the given channel
 * @addr: address of the channel
 *
 * Can sleep
 */
static int reset_stopbit(uint16_t addr)
{
<------>int ret;
<------>uint8_t data;
<------>ret = intel_msic_reg_read(addr, &data);
<------>if (ret)
<------><------>return ret;
<------>/* Set the stop bit to zero */
<------>return intel_msic_reg_write(addr, (data & 0xEF));
}
 
/**
 * find_free_channel - finds an empty channel for conversion
 *
 * If the ADC is not enabled then start using 0th channel
 * itself. Otherwise find an empty channel by looking for a
 * channel in which the stopbit is set to 1. returns the index
 * of the first free channel if succeeds or an error code.
 *
 * Context: can sleep
 *
 * FIXME: Ultimately the channel allocator will move into the intel_scu_ipc
 * code.
 */
static int find_free_channel(void)
{
<------>int ret;
<------>int i;
<------>uint8_t data;
 
<------>/* check whether ADC is enabled */
<------>ret = intel_msic_reg_read(INTEL_MSIC_ADC1CNTL1, &data);
<------>if (ret)
<------><------>return ret;
 
<------>if ((data & MSIC_ADC_ENBL) == 0)
<------><------>return 0;
 
<------>/* ADC is already enabled; Looking for an empty channel */
<------>for (i = 0; i < ADC_CHANLS_MAX; i++) {
<------><------>ret = intel_msic_reg_read(ADC_CHNL_START_ADDR + i, &data);
<------><------>if (ret)
<------><------><------>return ret;
 
<------><------>if (data & MSIC_STOPBIT_MASK) {
<------><------><------>ret = i;
<------><------><------>break;
<------><------>}
<------>}
<------>return (ret > ADC_LOOP_MAX) ? (-EINVAL) : ret;
}
 
/**
 * mid_initialize_adc - initializing the ADC
 * @dev: our device structure
 *
 * Initialize the ADC for reading thermistor values. Can sleep.
 */
static int mid_initialize_adc(struct device *dev)
{
<------>u8  data;
<------>u16 base_addr;
<------>int ret;
 
<------>/*
<------> * Ensure that adctherm is disabled before we
<------> * initialize the ADC
<------> */
<------>ret = intel_msic_reg_read(INTEL_MSIC_ADC1CNTL3, &data);
<------>if (ret)
<------><------>return ret;
 
<------>data &= ~MSIC_ADCTHERM_MASK;
<------>ret = intel_msic_reg_write(INTEL_MSIC_ADC1CNTL3, data);
<------>if (ret)
<------><------>return ret;
 
<------>/* Index of the first channel in which the stop bit is set */
<------>channel_index = find_free_channel();
<------>if (channel_index < 0) {
<------><------>dev_err(dev, "No free ADC channels");
<------><------>return channel_index;
<------>}
 
<------>base_addr = ADC_CHNL_START_ADDR + channel_index;
 
<------>if (!(channel_index == 0 || channel_index == ADC_LOOP_MAX)) {
<------><------>/* Reset stop bit for channels other than 0 and 12 */
<------><------>ret = reset_stopbit(base_addr);
<------><------>if (ret)
<------><------><------>return ret;
 
<------><------>/* Index of the first free channel */
<------><------>base_addr++;
<------><------>channel_index++;
<------>}
 
<------>ret = set_up_therm_channel(base_addr);
<------>if (ret) {
<------><------>dev_err(dev, "unable to enable ADC");
<------><------>return ret;
<------>}
<------>dev_dbg(dev, "ADC initialization successful");
<------>return ret;
}
 
/**
 * initialize_sensor - sets default temp and timer ranges
 * @index: index of the sensor
 *
 * Context: can sleep
 */
static struct thermal_device_info *initialize_sensor(int index)
{
<------>struct thermal_device_info *td_info =
<------><------>kzalloc(sizeof(struct thermal_device_info), GFP_KERNEL);
 
<------>if (!td_info)
<------><------>return NULL;
 
<------>/* Set the base addr of the channel for this sensor */
<------>td_info->chnl_addr = ADC_DATA_START_ADDR + 2 * (channel_index + index);
<------>/* Sensor 3 is direct conversion */
<------>if (index == 3)
<------><------>td_info->direct = 1;
<------>return td_info;
}
 
#ifdef CONFIG_PM_SLEEP
/**
 * mid_thermal_resume - resume routine
 * @dev: device structure
 *
 * mid thermal resume: re-initializes the adc. Can sleep.
 */
static int mid_thermal_resume(struct device *dev)
{
<------>return mid_initialize_adc(dev);
}
 
/**
 * mid_thermal_suspend - suspend routine
 * @dev: device structure
 *
 * mid thermal suspend implements the suspend functionality
 * by stopping the ADC. Can sleep.
 */
static int mid_thermal_suspend(struct device *dev)
{
<------>/*
<------> * This just stops the ADC and does not disable it.
<------> * temporary workaround until we have a generic ADC driver.
<------> * If 0 is passed, it disables the ADC.
<------> */
<------>return configure_adc(0);
}
#endif
 
static SIMPLE_DEV_PM_OPS(mid_thermal_pm,
<------><------><------> mid_thermal_suspend, mid_thermal_resume);
 
/**
 * read_curr_temp - reads the current temperature and stores in temp
 * @temp: holds the current temperature value after reading
 *
 * Can sleep
 */
static int read_curr_temp(struct thermal_zone_device *tzd, int *temp)
{
<------>WARN_ON(tzd == NULL);
<------>return mid_read_temp(tzd, temp);
}
 
/* Can't be const */
static struct thermal_zone_device_ops tzd_ops = {
<------>.get_temp = read_curr_temp,
};
 
/**
 * mid_thermal_probe - mfld thermal initialize
 * @pdev: platform device structure
 *
 * mid thermal probe initializes the hardware and registers
 * all the sensors with the generic thermal framework. Can sleep.
 */
static int mid_thermal_probe(struct platform_device *pdev)
{
<------>static char *name[MSIC_THERMAL_SENSORS] = {
<------><------>"skin0", "skin1", "sys", "msicdie"
<------>};
 
<------>int ret;
<------>int i;
<------>struct platform_info *pinfo;
 
<------>pinfo = devm_kzalloc(&pdev->dev, sizeof(struct platform_info),
<------><------><------>     GFP_KERNEL);
<------>if (!pinfo)
<------><------>return -ENOMEM;
 
<------>/* Initializing the hardware */
<------>ret = mid_initialize_adc(&pdev->dev);
<------>if (ret) {
<------><------>dev_err(&pdev->dev, "ADC init failed");
<------><------>return ret;
<------>}
 
<------>/* Register each sensor with the generic thermal framework*/
<------>for (i = 0; i < MSIC_THERMAL_SENSORS; i++) {
<------><------>struct thermal_device_info *td_info = initialize_sensor(i);
 
<------><------>if (!td_info) {
<------><------><------>ret = -ENOMEM;
<------><------><------>goto err;
<------><------>}
<------><------>pinfo->tzd[i] = thermal_zone_device_register(name[i],
<------><------><------><------>0, 0, td_info, &tzd_ops, NULL, 0, 0);
<------><------>if (IS_ERR(pinfo->tzd[i])) {
<------><------><------>kfree(td_info);
<------><------><------>ret = PTR_ERR(pinfo->tzd[i]);
<------><------><------>goto err;
<------><------>}
<------><------>ret = thermal_zone_device_enable(pinfo->tzd[i]);
<------><------>if (ret) {
<------><------><------>kfree(td_info);
<------><------><------>thermal_zone_device_unregister(pinfo->tzd[i]);
<------><------><------>goto err;
<------><------>}
<------>}
 
<------>pinfo->pdev = pdev;
<------>platform_set_drvdata(pdev, pinfo);
<------>return 0;
 
err:
<------>while (--i >= 0) {
<------><------>kfree(pinfo->tzd[i]->devdata);
<------><------>thermal_zone_device_unregister(pinfo->tzd[i]);
<------>}
<------>configure_adc(0);
<------>return ret;
}
 
/**
 * mid_thermal_remove - mfld thermal finalize
 * @dev: platform device structure
 *
 * MLFD thermal remove unregisters all the sensors from the generic
 * thermal framework. Can sleep.
 */
static int mid_thermal_remove(struct platform_device *pdev)
{
<------>int i;
<------>struct platform_info *pinfo = platform_get_drvdata(pdev);
 
<------>for (i = 0; i < MSIC_THERMAL_SENSORS; i++) {
<------><------>kfree(pinfo->tzd[i]->devdata);
<------><------>thermal_zone_device_unregister(pinfo->tzd[i]);
<------>}
 
<------>/* Stop the ADC */
<------>return configure_adc(0);
}
 
#define DRIVER_NAME "msic_thermal"
 
static const struct platform_device_id therm_id_table[] = {
<------>{ DRIVER_NAME, 1 },
<------>{ }
};
MODULE_DEVICE_TABLE(platform, therm_id_table);
 
static struct platform_driver mid_thermal_driver = {
<------>.driver = {
<------><------>.name = DRIVER_NAME,
<------><------>.pm = &mid_thermal_pm,
<------>},
<------>.probe = mid_thermal_probe,
<------>.remove = mid_thermal_remove,
<------>.id_table = therm_id_table,
};
 
module_platform_driver(mid_thermal_driver);
 
MODULE_AUTHOR("Durgadoss R <durgadoss.r@intel.com>");
MODULE_DESCRIPTION("Intel Medfield Platform Thermal Driver");
MODULE_LICENSE("GPL v2");