+++ /dev/null
-// 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");