linux/drivers/thermal/qcom/qcom-spmi-adc-tm5.c
Colin Ian King 74369d041a thermal: qcom: Fix comparison with uninitialized variable channels_available
Currently the check of chip->channels[i].channel is against an the
uninitialized variable channels_available.  I believe the variable
channels_available needs to be fetched first by the call to adc_tm5_read
before the channels check. Fix the issue swapping the order of the
channels check loop with the call to adc_tm5_read.

Addresses-Coverity: ("Uninitialized scalar variable")
Fixes: ca66dca5ed ("thermal: qcom: add support for adc-tm5 PMIC thermal monitor")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>
Link: https://lore.kernel.org/r/20210216151626.162996-1-colin.king@canonical.com
2021-02-16 19:05:23 +01:00

624 lines
16 KiB
C

// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2020 Linaro Limited
*
* Based on original driver:
* Copyright (c) 2012-2020, The Linux Foundation. All rights reserved.
*/
#include <linux/bitfield.h>
#include <linux/iio/adc/qcom-vadc-common.h>
#include <linux/iio/consumer.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
#include <linux/regmap.h>
#include <linux/thermal.h>
/*
* Thermal monitoring block consists of 8 (ADC_TM5_NUM_CHANNELS) channels. Each
* channel is programmed to use one of ADC channels for voltage comparison.
* Voltages are programmed using ADC codes, so we have to convert temp to
* voltage and then to ADC code value.
*
* Configuration of TM channels must match configuration of corresponding ADC
* channels.
*/
#define ADC5_MAX_CHANNEL 0xc0
#define ADC_TM5_NUM_CHANNELS 8
#define ADC_TM5_STATUS_LOW 0x0a
#define ADC_TM5_STATUS_HIGH 0x0b
#define ADC_TM5_NUM_BTM 0x0f
#define ADC_TM5_ADC_DIG_PARAM 0x42
#define ADC_TM5_FAST_AVG_CTL (ADC_TM5_ADC_DIG_PARAM + 1)
#define ADC_TM5_FAST_AVG_EN BIT(7)
#define ADC_TM5_MEAS_INTERVAL_CTL (ADC_TM5_ADC_DIG_PARAM + 2)
#define ADC_TM5_TIMER1 3 /* 3.9ms */
#define ADC_TM5_MEAS_INTERVAL_CTL2 (ADC_TM5_ADC_DIG_PARAM + 3)
#define ADC_TM5_MEAS_INTERVAL_CTL2_MASK 0xf0
#define ADC_TM5_TIMER2 10 /* 1 second */
#define ADC_TM5_MEAS_INTERVAL_CTL3_MASK 0xf
#define ADC_TM5_TIMER3 4 /* 4 second */
#define ADC_TM_EN_CTL1 0x46
#define ADC_TM_EN BIT(7)
#define ADC_TM_CONV_REQ 0x47
#define ADC_TM_CONV_REQ_EN BIT(7)
#define ADC_TM5_M_CHAN_BASE 0x60
#define ADC_TM5_M_ADC_CH_SEL_CTL(n) (ADC_TM5_M_CHAN_BASE + ((n) * 8) + 0)
#define ADC_TM5_M_LOW_THR0(n) (ADC_TM5_M_CHAN_BASE + ((n) * 8) + 1)
#define ADC_TM5_M_LOW_THR1(n) (ADC_TM5_M_CHAN_BASE + ((n) * 8) + 2)
#define ADC_TM5_M_HIGH_THR0(n) (ADC_TM5_M_CHAN_BASE + ((n) * 8) + 3)
#define ADC_TM5_M_HIGH_THR1(n) (ADC_TM5_M_CHAN_BASE + ((n) * 8) + 4)
#define ADC_TM5_M_MEAS_INTERVAL_CTL(n) (ADC_TM5_M_CHAN_BASE + ((n) * 8) + 5)
#define ADC_TM5_M_CTL(n) (ADC_TM5_M_CHAN_BASE + ((n) * 8) + 6)
#define ADC_TM5_M_CTL_HW_SETTLE_DELAY_MASK 0xf
#define ADC_TM5_M_CTL_CAL_SEL_MASK 0x30
#define ADC_TM5_M_CTL_CAL_VAL 0x40
#define ADC_TM5_M_EN(n) (ADC_TM5_M_CHAN_BASE + ((n) * 8) + 7)
#define ADC_TM5_M_MEAS_EN BIT(7)
#define ADC_TM5_M_HIGH_THR_INT_EN BIT(1)
#define ADC_TM5_M_LOW_THR_INT_EN BIT(0)
enum adc5_timer_select {
ADC5_TIMER_SEL_1 = 0,
ADC5_TIMER_SEL_2,
ADC5_TIMER_SEL_3,
ADC5_TIMER_SEL_NONE,
};
struct adc_tm5_data {
const u32 full_scale_code_volt;
unsigned int *decimation;
unsigned int *hw_settle;
};
enum adc_tm5_cal_method {
ADC_TM5_NO_CAL = 0,
ADC_TM5_RATIOMETRIC_CAL,
ADC_TM5_ABSOLUTE_CAL
};
struct adc_tm5_chip;
/**
* struct adc_tm5_channel - ADC Thermal Monitoring channel data.
* @channel: channel number.
* @adc_channel: corresponding ADC channel number.
* @cal_method: calibration method.
* @prescale: channel scaling performed on the input signal.
* @hw_settle_time: the time between AMUX being configured and the
* start of conversion.
* @iio: IIO channel instance used by this channel.
* @chip: ADC TM chip instance.
* @tzd: thermal zone device used by this channel.
*/
struct adc_tm5_channel {
unsigned int channel;
unsigned int adc_channel;
enum adc_tm5_cal_method cal_method;
unsigned int prescale;
unsigned int hw_settle_time;
struct iio_channel *iio;
struct adc_tm5_chip *chip;
struct thermal_zone_device *tzd;
};
/**
* struct adc_tm5_chip - ADC Thermal Monitoring properties
* @regmap: SPMI ADC5 Thermal Monitoring peripheral register map field.
* @dev: SPMI ADC5 device.
* @data: software configuration data.
* @channels: array of ADC TM channel data.
* @nchannels: amount of channels defined/allocated
* @decimation: sampling rate supported for the channel.
* @avg_samples: ability to provide single result from the ADC
* that is an average of multiple measurements.
* @base: base address of TM registers.
*/
struct adc_tm5_chip {
struct regmap *regmap;
struct device *dev;
const struct adc_tm5_data *data;
struct adc_tm5_channel *channels;
unsigned int nchannels;
unsigned int decimation;
unsigned int avg_samples;
u16 base;
};
static const struct adc_tm5_data adc_tm5_data_pmic = {
.full_scale_code_volt = 0x70e4,
.decimation = (unsigned int []) { 250, 420, 840 },
.hw_settle = (unsigned int []) { 15, 100, 200, 300, 400, 500, 600, 700,
1000, 2000, 4000, 8000, 16000, 32000,
64000, 128000 },
};
static int adc_tm5_read(struct adc_tm5_chip *adc_tm, u16 offset, u8 *data, int len)
{
return regmap_bulk_read(adc_tm->regmap, adc_tm->base + offset, data, len);
}
static int adc_tm5_write(struct adc_tm5_chip *adc_tm, u16 offset, u8 *data, int len)
{
return regmap_bulk_write(adc_tm->regmap, adc_tm->base + offset, data, len);
}
static int adc_tm5_reg_update(struct adc_tm5_chip *adc_tm, u16 offset, u8 mask, u8 val)
{
return regmap_write_bits(adc_tm->regmap, adc_tm->base + offset, mask, val);
}
static irqreturn_t adc_tm5_isr(int irq, void *data)
{
struct adc_tm5_chip *chip = data;
u8 status_low, status_high, ctl;
int ret, i;
ret = adc_tm5_read(chip, ADC_TM5_STATUS_LOW, &status_low, sizeof(status_low));
if (unlikely(ret)) {
dev_err(chip->dev, "read status low failed: %d\n", ret);
return IRQ_HANDLED;
}
ret = adc_tm5_read(chip, ADC_TM5_STATUS_HIGH, &status_high, sizeof(status_high));
if (unlikely(ret)) {
dev_err(chip->dev, "read status high failed: %d\n", ret);
return IRQ_HANDLED;
}
for (i = 0; i < chip->nchannels; i++) {
bool upper_set = false, lower_set = false;
unsigned int ch = chip->channels[i].channel;
/* No TZD, we warned at the boot time */
if (!chip->channels[i].tzd)
continue;
ret = adc_tm5_read(chip, ADC_TM5_M_EN(ch), &ctl, sizeof(ctl));
if (unlikely(ret)) {
dev_err(chip->dev, "ctl read failed: %d, channel %d\n", ret, i);
continue;
}
if (!(ctl & ADC_TM5_M_MEAS_EN))
continue;
lower_set = (status_low & BIT(ch)) &&
(ctl & ADC_TM5_M_LOW_THR_INT_EN);
upper_set = (status_high & BIT(ch)) &&
(ctl & ADC_TM5_M_HIGH_THR_INT_EN);
if (upper_set || lower_set)
thermal_zone_device_update(chip->channels[i].tzd,
THERMAL_EVENT_UNSPECIFIED);
}
return IRQ_HANDLED;
}
static int adc_tm5_get_temp(void *data, int *temp)
{
struct adc_tm5_channel *channel = data;
int ret;
if (!channel || !channel->iio)
return -EINVAL;
ret = iio_read_channel_processed(channel->iio, temp);
if (ret < 0)
return ret;
if (ret != IIO_VAL_INT)
return -EINVAL;
return 0;
}
static int adc_tm5_disable_channel(struct adc_tm5_channel *channel)
{
struct adc_tm5_chip *chip = channel->chip;
unsigned int reg = ADC_TM5_M_EN(channel->channel);
return adc_tm5_reg_update(chip, reg,
ADC_TM5_M_MEAS_EN |
ADC_TM5_M_HIGH_THR_INT_EN |
ADC_TM5_M_LOW_THR_INT_EN,
0);
}
static int adc_tm5_enable(struct adc_tm5_chip *chip)
{
int ret;
u8 data;
data = ADC_TM_EN;
ret = adc_tm5_write(chip, ADC_TM_EN_CTL1, &data, sizeof(data));
if (ret < 0) {
dev_err(chip->dev, "adc-tm enable failed\n");
return ret;
}
data = ADC_TM_CONV_REQ_EN;
ret = adc_tm5_write(chip, ADC_TM_CONV_REQ, &data, sizeof(data));
if (ret < 0) {
dev_err(chip->dev, "adc-tm request conversion failed\n");
return ret;
}
return 0;
}
static int adc_tm5_configure(struct adc_tm5_channel *channel, int low, int high)
{
struct adc_tm5_chip *chip = channel->chip;
u8 buf[8];
u16 reg = ADC_TM5_M_ADC_CH_SEL_CTL(channel->channel);
int ret;
ret = adc_tm5_read(chip, reg, buf, sizeof(buf));
if (ret) {
dev_err(chip->dev, "channel %d params read failed: %d\n", channel->channel, ret);
return ret;
}
buf[0] = channel->adc_channel;
/* High temperature corresponds to low voltage threshold */
if (high != INT_MAX) {
u16 adc_code = qcom_adc_tm5_temp_volt_scale(channel->prescale,
chip->data->full_scale_code_volt, high);
buf[1] = adc_code & 0xff;
buf[2] = adc_code >> 8;
buf[7] |= ADC_TM5_M_LOW_THR_INT_EN;
} else {
buf[7] &= ~ADC_TM5_M_LOW_THR_INT_EN;
}
/* Low temperature corresponds to high voltage threshold */
if (low != -INT_MAX) {
u16 adc_code = qcom_adc_tm5_temp_volt_scale(channel->prescale,
chip->data->full_scale_code_volt, low);
buf[3] = adc_code & 0xff;
buf[4] = adc_code >> 8;
buf[7] |= ADC_TM5_M_HIGH_THR_INT_EN;
} else {
buf[7] &= ~ADC_TM5_M_HIGH_THR_INT_EN;
}
buf[5] = ADC5_TIMER_SEL_2;
/* Set calibration select, hw_settle delay */
buf[6] &= ~ADC_TM5_M_CTL_HW_SETTLE_DELAY_MASK;
buf[6] |= FIELD_PREP(ADC_TM5_M_CTL_HW_SETTLE_DELAY_MASK, channel->hw_settle_time);
buf[6] &= ~ADC_TM5_M_CTL_CAL_SEL_MASK;
buf[6] |= FIELD_PREP(ADC_TM5_M_CTL_CAL_SEL_MASK, channel->cal_method);
buf[7] |= ADC_TM5_M_MEAS_EN;
ret = adc_tm5_write(chip, reg, buf, sizeof(buf));
if (ret) {
dev_err(chip->dev, "channel %d params write failed: %d\n", channel->channel, ret);
return ret;
}
return adc_tm5_enable(chip);
}
static int adc_tm5_set_trips(void *data, int low, int high)
{
struct adc_tm5_channel *channel = data;
struct adc_tm5_chip *chip;
int ret;
if (!channel)
return -EINVAL;
chip = channel->chip;
dev_dbg(chip->dev, "%d:low(mdegC):%d, high(mdegC):%d\n",
channel->channel, low, high);
if (high == INT_MAX && low <= -INT_MAX)
ret = adc_tm5_disable_channel(channel);
else
ret = adc_tm5_configure(channel, low, high);
return ret;
}
static struct thermal_zone_of_device_ops adc_tm5_ops = {
.get_temp = adc_tm5_get_temp,
.set_trips = adc_tm5_set_trips,
};
static int adc_tm5_register_tzd(struct adc_tm5_chip *adc_tm)
{
unsigned int i;
struct thermal_zone_device *tzd;
for (i = 0; i < adc_tm->nchannels; i++) {
adc_tm->channels[i].chip = adc_tm;
tzd = devm_thermal_zone_of_sensor_register(adc_tm->dev,
adc_tm->channels[i].channel,
&adc_tm->channels[i],
&adc_tm5_ops);
if (IS_ERR(tzd)) {
dev_err(adc_tm->dev, "Error registering TZ zone for channel %d: %ld\n",
adc_tm->channels[i].channel, PTR_ERR(tzd));
return PTR_ERR(tzd);
}
adc_tm->channels[i].tzd = tzd;
}
return 0;
}
static int adc_tm5_init(struct adc_tm5_chip *chip)
{
u8 buf[4], channels_available;
int ret;
unsigned int i;
ret = adc_tm5_read(chip, ADC_TM5_NUM_BTM,
&channels_available, sizeof(channels_available));
if (ret) {
dev_err(chip->dev, "read failed for BTM channels\n");
return ret;
}
for (i = 0; i < chip->nchannels; i++) {
if (chip->channels[i].channel >= channels_available) {
dev_err(chip->dev, "Invalid channel %d\n", chip->channels[i].channel);
return -EINVAL;
}
}
buf[0] = chip->decimation;
buf[1] = chip->avg_samples | ADC_TM5_FAST_AVG_EN;
buf[2] = ADC_TM5_TIMER1;
buf[3] = FIELD_PREP(ADC_TM5_MEAS_INTERVAL_CTL2_MASK, ADC_TM5_TIMER2) |
FIELD_PREP(ADC_TM5_MEAS_INTERVAL_CTL3_MASK, ADC_TM5_TIMER3);
ret = adc_tm5_write(chip, ADC_TM5_ADC_DIG_PARAM, buf, sizeof(buf));
if (ret) {
dev_err(chip->dev, "block write failed: %d\n", ret);
return ret;
}
return ret;
}
static int adc_tm5_get_dt_channel_data(struct adc_tm5_chip *adc_tm,
struct adc_tm5_channel *channel,
struct device_node *node)
{
const char *name = node->name;
u32 chan, value, varr[2];
int ret;
struct device *dev = adc_tm->dev;
struct of_phandle_args args;
ret = of_property_read_u32(node, "reg", &chan);
if (ret) {
dev_err(dev, "%s: invalid channel number %d\n", name, ret);
return ret;
}
if (chan >= ADC_TM5_NUM_CHANNELS) {
dev_err(dev, "%s: channel number too big: %d\n", name, chan);
return -EINVAL;
}
channel->channel = chan;
/*
* We are tied to PMIC's ADC controller, which always use single
* argument for channel number. So don't bother parsing
* #io-channel-cells, just enforce cell_count = 1.
*/
ret = of_parse_phandle_with_fixed_args(node, "io-channels", 1, 0, &args);
if (ret < 0) {
dev_err(dev, "%s: error parsing ADC channel number %d: %d\n", name, chan, ret);
return ret;
}
of_node_put(args.np);
if (args.args_count != 1 || args.args[0] >= ADC5_MAX_CHANNEL) {
dev_err(dev, "%s: invalid ADC channel number %d\n", name, chan);
return ret;
}
channel->adc_channel = args.args[0];
channel->iio = devm_of_iio_channel_get_by_name(adc_tm->dev, node, NULL);
if (IS_ERR(channel->iio)) {
ret = PTR_ERR(channel->iio);
if (ret != -EPROBE_DEFER)
dev_err(dev, "%s: error getting channel: %d\n", name, ret);
return ret;
}
ret = of_property_read_u32_array(node, "qcom,pre-scaling", varr, 2);
if (!ret) {
ret = qcom_adc5_prescaling_from_dt(varr[0], varr[1]);
if (ret < 0) {
dev_err(dev, "%s: invalid pre-scaling <%d %d>\n",
name, varr[0], varr[1]);
return ret;
}
channel->prescale = ret;
} else {
/* 1:1 prescale is index 0 */
channel->prescale = 0;
}
ret = of_property_read_u32(node, "qcom,hw-settle-time-us", &value);
if (!ret) {
ret = qcom_adc5_hw_settle_time_from_dt(value, adc_tm->data->hw_settle);
if (ret < 0) {
dev_err(dev, "%s invalid hw-settle-time-us %d us\n",
name, value);
return ret;
}
channel->hw_settle_time = ret;
} else {
channel->hw_settle_time = VADC_DEF_HW_SETTLE_TIME;
}
if (of_property_read_bool(node, "qcom,ratiometric"))
channel->cal_method = ADC_TM5_RATIOMETRIC_CAL;
else
channel->cal_method = ADC_TM5_ABSOLUTE_CAL;
return 0;
}
static int adc_tm5_get_dt_data(struct adc_tm5_chip *adc_tm, struct device_node *node)
{
struct adc_tm5_channel *channels;
struct device_node *child;
u32 value;
int ret;
struct device *dev = adc_tm->dev;
adc_tm->nchannels = of_get_available_child_count(node);
if (!adc_tm->nchannels)
return -EINVAL;
adc_tm->channels = devm_kcalloc(dev, adc_tm->nchannels,
sizeof(*adc_tm->channels), GFP_KERNEL);
if (!adc_tm->channels)
return -ENOMEM;
channels = adc_tm->channels;
adc_tm->data = of_device_get_match_data(dev);
if (!adc_tm->data)
adc_tm->data = &adc_tm5_data_pmic;
ret = of_property_read_u32(node, "qcom,decimation", &value);
if (!ret) {
ret = qcom_adc5_decimation_from_dt(value, adc_tm->data->decimation);
if (ret < 0) {
dev_err(dev, "invalid decimation %d\n", value);
return ret;
}
adc_tm->decimation = ret;
} else {
adc_tm->decimation = ADC5_DECIMATION_DEFAULT;
}
ret = of_property_read_u32(node, "qcom,avg-samples", &value);
if (!ret) {
ret = qcom_adc5_avg_samples_from_dt(value);
if (ret < 0) {
dev_err(dev, "invalid avg-samples %d\n", value);
return ret;
}
adc_tm->avg_samples = ret;
} else {
adc_tm->avg_samples = VADC_DEF_AVG_SAMPLES;
}
for_each_available_child_of_node(node, child) {
ret = adc_tm5_get_dt_channel_data(adc_tm, channels, child);
if (ret) {
of_node_put(child);
return ret;
}
channels++;
}
return 0;
}
static int adc_tm5_probe(struct platform_device *pdev)
{
struct device_node *node = pdev->dev.of_node;
struct device *dev = &pdev->dev;
struct adc_tm5_chip *adc_tm;
struct regmap *regmap;
int ret, irq;
u32 reg;
regmap = dev_get_regmap(dev->parent, NULL);
if (!regmap)
return -ENODEV;
ret = of_property_read_u32(node, "reg", &reg);
if (ret)
return ret;
adc_tm = devm_kzalloc(&pdev->dev, sizeof(*adc_tm), GFP_KERNEL);
if (!adc_tm)
return -ENOMEM;
adc_tm->regmap = regmap;
adc_tm->dev = dev;
adc_tm->base = reg;
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
dev_err(dev, "get_irq failed: %d\n", irq);
return irq;
}
ret = adc_tm5_get_dt_data(adc_tm, node);
if (ret) {
dev_err(dev, "get dt data failed: %d\n", ret);
return ret;
}
ret = adc_tm5_init(adc_tm);
if (ret) {
dev_err(dev, "adc-tm init failed\n");
return ret;
}
ret = adc_tm5_register_tzd(adc_tm);
if (ret) {
dev_err(dev, "tzd register failed\n");
return ret;
}
return devm_request_threaded_irq(dev, irq, NULL, adc_tm5_isr,
IRQF_ONESHOT, "pm-adc-tm5", adc_tm);
}
static const struct of_device_id adc_tm5_match_table[] = {
{
.compatible = "qcom,spmi-adc-tm5",
.data = &adc_tm5_data_pmic,
},
{ }
};
MODULE_DEVICE_TABLE(of, adc_tm5_match_table);
static struct platform_driver adc_tm5_driver = {
.driver = {
.name = "qcom-spmi-adc-tm5",
.of_match_table = adc_tm5_match_table,
},
.probe = adc_tm5_probe,
};
module_platform_driver(adc_tm5_driver);
MODULE_DESCRIPTION("SPMI PMIC Thermal Monitor ADC driver");
MODULE_LICENSE("GPL v2");