linux/drivers/thermal/ti-soc-thermal/ti-bandgap.c
Ranganath Krishnan e838ff8119 thermal: ti-soc-thermal: Ensure to compute thermal trend
Workaround to compute thermal trend even when update interval
is not set. This patch will ensure to compute the thermal trend
when bandgap counter delay is not set.

Signed-off-by: Ranganath Krishnan <ranganath@ti.com>
Signed-off-by: Eduardo Valentin <eduardo.valentin@ti.com>
2013-08-29 09:36:18 -04:00

1561 lines
40 KiB
C

/*
* TI Bandgap temperature sensor driver
*
* Copyright (C) 2011-2012 Texas Instruments Incorporated - http://www.ti.com/
* Author: J Keerthy <j-keerthy@ti.com>
* Author: Moiz Sonasath <m-sonasath@ti.com>
* Couple of fixes, DT and MFD adaptation:
* Eduardo Valentin <eduardo.valentin@ti.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* version 2 as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*
*/
#include <linux/module.h>
#include <linux/export.h>
#include <linux/init.h>
#include <linux/kernel.h>
#include <linux/interrupt.h>
#include <linux/clk.h>
#include <linux/gpio.h>
#include <linux/platform_device.h>
#include <linux/err.h>
#include <linux/types.h>
#include <linux/spinlock.h>
#include <linux/reboot.h>
#include <linux/of_device.h>
#include <linux/of_platform.h>
#include <linux/of_irq.h>
#include <linux/of_gpio.h>
#include <linux/io.h>
#include "ti-bandgap.h"
/*** Helper functions to access registers and their bitfields ***/
/**
* ti_bandgap_readl() - simple read helper function
* @bgp: pointer to ti_bandgap structure
* @reg: desired register (offset) to be read
*
* Helper function to read bandgap registers. It uses the io remapped area.
* Return: the register value.
*/
static u32 ti_bandgap_readl(struct ti_bandgap *bgp, u32 reg)
{
return readl(bgp->base + reg);
}
/**
* ti_bandgap_writel() - simple write helper function
* @bgp: pointer to ti_bandgap structure
* @val: desired register value to be written
* @reg: desired register (offset) to be written
*
* Helper function to write bandgap registers. It uses the io remapped area.
*/
static void ti_bandgap_writel(struct ti_bandgap *bgp, u32 val, u32 reg)
{
writel(val, bgp->base + reg);
}
/**
* DOC: macro to update bits.
*
* RMW_BITS() - used to read, modify and update bandgap bitfields.
* The value passed will be shifted.
*/
#define RMW_BITS(bgp, id, reg, mask, val) \
do { \
struct temp_sensor_registers *t; \
u32 r; \
\
t = bgp->conf->sensors[(id)].registers; \
r = ti_bandgap_readl(bgp, t->reg); \
r &= ~t->mask; \
r |= (val) << __ffs(t->mask); \
ti_bandgap_writel(bgp, r, t->reg); \
} while (0)
/*** Basic helper functions ***/
/**
* ti_bandgap_power() - controls the power state of a bandgap device
* @bgp: pointer to ti_bandgap structure
* @on: desired power state (1 - on, 0 - off)
*
* Used to power on/off a bandgap device instance. Only used on those
* that features tempsoff bit.
*
* Return: 0 on success, -ENOTSUPP if tempsoff is not supported.
*/
static int ti_bandgap_power(struct ti_bandgap *bgp, bool on)
{
int i, ret = 0;
if (!TI_BANDGAP_HAS(bgp, POWER_SWITCH)) {
ret = -ENOTSUPP;
goto exit;
}
for (i = 0; i < bgp->conf->sensor_count; i++)
/* active on 0 */
RMW_BITS(bgp, i, temp_sensor_ctrl, bgap_tempsoff_mask, !on);
exit:
return ret;
}
/**
* ti_bandgap_read_temp() - helper function to read sensor temperature
* @bgp: pointer to ti_bandgap structure
* @id: bandgap sensor id
*
* Function to concentrate the steps to read sensor temperature register.
* This function is desired because, depending on bandgap device version,
* it might be needed to freeze the bandgap state machine, before fetching
* the register value.
*
* Return: temperature in ADC values.
*/
static u32 ti_bandgap_read_temp(struct ti_bandgap *bgp, int id)
{
struct temp_sensor_registers *tsr;
u32 temp, reg;
tsr = bgp->conf->sensors[id].registers;
reg = tsr->temp_sensor_ctrl;
if (TI_BANDGAP_HAS(bgp, FREEZE_BIT)) {
RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 1);
/*
* In case we cannot read from cur_dtemp / dtemp_0,
* then we read from the last valid temp read
*/
reg = tsr->ctrl_dtemp_1;
}
/* read temperature */
temp = ti_bandgap_readl(bgp, reg);
temp &= tsr->bgap_dtemp_mask;
if (TI_BANDGAP_HAS(bgp, FREEZE_BIT))
RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 0);
return temp;
}
/*** IRQ handlers ***/
/**
* ti_bandgap_talert_irq_handler() - handles Temperature alert IRQs
* @irq: IRQ number
* @data: private data (struct ti_bandgap *)
*
* This is the Talert handler. Use it only if bandgap device features
* HAS(TALERT). This handler goes over all sensors and checks their
* conditions and acts accordingly. In case there are events pending,
* it will reset the event mask to wait for the opposite event (next event).
* Every time there is a new event, it will be reported to thermal layer.
*
* Return: IRQ_HANDLED
*/
static irqreturn_t ti_bandgap_talert_irq_handler(int irq, void *data)
{
struct ti_bandgap *bgp = data;
struct temp_sensor_registers *tsr;
u32 t_hot = 0, t_cold = 0, ctrl;
int i;
spin_lock(&bgp->lock);
for (i = 0; i < bgp->conf->sensor_count; i++) {
tsr = bgp->conf->sensors[i].registers;
ctrl = ti_bandgap_readl(bgp, tsr->bgap_status);
/* Read the status of t_hot */
t_hot = ctrl & tsr->status_hot_mask;
/* Read the status of t_cold */
t_cold = ctrl & tsr->status_cold_mask;
if (!t_cold && !t_hot)
continue;
ctrl = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl);
/*
* One TALERT interrupt: Two sources
* If the interrupt is due to t_hot then mask t_hot and
* and unmask t_cold else mask t_cold and unmask t_hot
*/
if (t_hot) {
ctrl &= ~tsr->mask_hot_mask;
ctrl |= tsr->mask_cold_mask;
} else if (t_cold) {
ctrl &= ~tsr->mask_cold_mask;
ctrl |= tsr->mask_hot_mask;
}
ti_bandgap_writel(bgp, ctrl, tsr->bgap_mask_ctrl);
dev_dbg(bgp->dev,
"%s: IRQ from %s sensor: hotevent %d coldevent %d\n",
__func__, bgp->conf->sensors[i].domain,
t_hot, t_cold);
/* report temperature to whom may concern */
if (bgp->conf->report_temperature)
bgp->conf->report_temperature(bgp, i);
}
spin_unlock(&bgp->lock);
return IRQ_HANDLED;
}
/**
* ti_bandgap_tshut_irq_handler() - handles Temperature shutdown signal
* @irq: IRQ number
* @data: private data (unused)
*
* This is the Tshut handler. Use it only if bandgap device features
* HAS(TSHUT). If any sensor fires the Tshut signal, we simply shutdown
* the system.
*
* Return: IRQ_HANDLED
*/
static irqreturn_t ti_bandgap_tshut_irq_handler(int irq, void *data)
{
pr_emerg("%s: TSHUT temperature reached. Needs shut down...\n",
__func__);
orderly_poweroff(true);
return IRQ_HANDLED;
}
/*** Helper functions which manipulate conversion ADC <-> mi Celsius ***/
/**
* ti_bandgap_adc_to_mcelsius() - converts an ADC value to mCelsius scale
* @bgp: struct ti_bandgap pointer
* @adc_val: value in ADC representation
* @t: address where to write the resulting temperature in mCelsius
*
* Simple conversion from ADC representation to mCelsius. In case the ADC value
* is out of the ADC conv table range, it returns -ERANGE, 0 on success.
* The conversion table is indexed by the ADC values.
*
* Return: 0 if conversion was successful, else -ERANGE in case the @adc_val
* argument is out of the ADC conv table range.
*/
static
int ti_bandgap_adc_to_mcelsius(struct ti_bandgap *bgp, int adc_val, int *t)
{
const struct ti_bandgap_data *conf = bgp->conf;
int ret = 0;
/* look up for temperature in the table and return the temperature */
if (adc_val < conf->adc_start_val || adc_val > conf->adc_end_val) {
ret = -ERANGE;
goto exit;
}
*t = bgp->conf->conv_table[adc_val - conf->adc_start_val];
exit:
return ret;
}
/**
* ti_bandgap_mcelsius_to_adc() - converts a mCelsius value to ADC scale
* @bgp: struct ti_bandgap pointer
* @temp: value in mCelsius
* @adc: address where to write the resulting temperature in ADC representation
*
* Simple conversion from mCelsius to ADC values. In case the temp value
* is out of the ADC conv table range, it returns -ERANGE, 0 on success.
* The conversion table is indexed by the ADC values.
*
* Return: 0 if conversion was successful, else -ERANGE in case the @temp
* argument is out of the ADC conv table range.
*/
static
int ti_bandgap_mcelsius_to_adc(struct ti_bandgap *bgp, long temp, int *adc)
{
const struct ti_bandgap_data *conf = bgp->conf;
const int *conv_table = bgp->conf->conv_table;
int high, low, mid, ret = 0;
low = 0;
high = conf->adc_end_val - conf->adc_start_val;
mid = (high + low) / 2;
if (temp < conv_table[low] || temp > conv_table[high]) {
ret = -ERANGE;
goto exit;
}
while (low < high) {
if (temp < conv_table[mid])
high = mid - 1;
else
low = mid + 1;
mid = (low + high) / 2;
}
*adc = conf->adc_start_val + low;
exit:
return ret;
}
/**
* ti_bandgap_add_hyst() - add hysteresis (in mCelsius) to an ADC value
* @bgp: struct ti_bandgap pointer
* @adc_val: temperature value in ADC representation
* @hyst_val: hysteresis value in mCelsius
* @sum: address where to write the resulting temperature (in ADC scale)
*
* Adds an hysteresis value (in mCelsius) to a ADC temperature value.
*
* Return: 0 on success, -ERANGE otherwise.
*/
static
int ti_bandgap_add_hyst(struct ti_bandgap *bgp, int adc_val, int hyst_val,
u32 *sum)
{
int temp, ret;
/*
* Need to add in the mcelsius domain, so we have a temperature
* the conv_table range
*/
ret = ti_bandgap_adc_to_mcelsius(bgp, adc_val, &temp);
if (ret < 0)
goto exit;
temp += hyst_val;
ret = ti_bandgap_mcelsius_to_adc(bgp, temp, sum);
exit:
return ret;
}
/*** Helper functions handling device Alert/Shutdown signals ***/
/**
* ti_bandgap_unmask_interrupts() - unmasks the events of thot & tcold
* @bgp: struct ti_bandgap pointer
* @id: bandgap sensor id
* @t_hot: hot temperature value to trigger alert signal
* @t_cold: cold temperature value to trigger alert signal
*
* Checks the requested t_hot and t_cold values and configures the IRQ event
* masks accordingly. Call this function only if bandgap features HAS(TALERT).
*/
static void ti_bandgap_unmask_interrupts(struct ti_bandgap *bgp, int id,
u32 t_hot, u32 t_cold)
{
struct temp_sensor_registers *tsr;
u32 temp, reg_val;
/* Read the current on die temperature */
temp = ti_bandgap_read_temp(bgp, id);
tsr = bgp->conf->sensors[id].registers;
reg_val = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl);
if (temp < t_hot)
reg_val |= tsr->mask_hot_mask;
else
reg_val &= ~tsr->mask_hot_mask;
if (t_cold < temp)
reg_val |= tsr->mask_cold_mask;
else
reg_val &= ~tsr->mask_cold_mask;
ti_bandgap_writel(bgp, reg_val, tsr->bgap_mask_ctrl);
}
/**
* ti_bandgap_update_alert_threshold() - sequence to update thresholds
* @bgp: struct ti_bandgap pointer
* @id: bandgap sensor id
* @val: value (ADC) of a new threshold
* @hot: desired threshold to be updated. true if threshold hot, false if
* threshold cold
*
* It will program the required thresholds (hot and cold) for TALERT signal.
* This function can be used to update t_hot or t_cold, depending on @hot value.
* It checks the resulting t_hot and t_cold values, based on the new passed @val
* and configures the thresholds so that t_hot is always greater than t_cold.
* Call this function only if bandgap features HAS(TALERT).
*
* Return: 0 if no error, else corresponding error
*/
static int ti_bandgap_update_alert_threshold(struct ti_bandgap *bgp, int id,
int val, bool hot)
{
struct temp_sensor_data *ts_data = bgp->conf->sensors[id].ts_data;
struct temp_sensor_registers *tsr;
u32 thresh_val, reg_val, t_hot, t_cold;
int err = 0;
tsr = bgp->conf->sensors[id].registers;
/* obtain the current value */
thresh_val = ti_bandgap_readl(bgp, tsr->bgap_threshold);
t_cold = (thresh_val & tsr->threshold_tcold_mask) >>
__ffs(tsr->threshold_tcold_mask);
t_hot = (thresh_val & tsr->threshold_thot_mask) >>
__ffs(tsr->threshold_thot_mask);
if (hot)
t_hot = val;
else
t_cold = val;
if (t_cold > t_hot) {
if (hot)
err = ti_bandgap_add_hyst(bgp, t_hot,
-ts_data->hyst_val,
&t_cold);
else
err = ti_bandgap_add_hyst(bgp, t_cold,
ts_data->hyst_val,
&t_hot);
}
/* write the new threshold values */
reg_val = thresh_val &
~(tsr->threshold_thot_mask | tsr->threshold_tcold_mask);
reg_val |= (t_hot << __ffs(tsr->threshold_thot_mask)) |
(t_cold << __ffs(tsr->threshold_tcold_mask));
ti_bandgap_writel(bgp, reg_val, tsr->bgap_threshold);
if (err) {
dev_err(bgp->dev, "failed to reprogram thot threshold\n");
err = -EIO;
goto exit;
}
ti_bandgap_unmask_interrupts(bgp, id, t_hot, t_cold);
exit:
return err;
}
/**
* ti_bandgap_validate() - helper to check the sanity of a struct ti_bandgap
* @bgp: struct ti_bandgap pointer
* @id: bandgap sensor id
*
* Checks if the bandgap pointer is valid and if the sensor id is also
* applicable.
*
* Return: 0 if no errors, -EINVAL for invalid @bgp pointer or -ERANGE if
* @id cannot index @bgp sensors.
*/
static inline int ti_bandgap_validate(struct ti_bandgap *bgp, int id)
{
int ret = 0;
if (!bgp || IS_ERR(bgp)) {
pr_err("%s: invalid bandgap pointer\n", __func__);
ret = -EINVAL;
goto exit;
}
if ((id < 0) || (id >= bgp->conf->sensor_count)) {
dev_err(bgp->dev, "%s: sensor id out of range (%d)\n",
__func__, id);
ret = -ERANGE;
}
exit:
return ret;
}
/**
* _ti_bandgap_write_threshold() - helper to update TALERT t_cold or t_hot
* @bgp: struct ti_bandgap pointer
* @id: bandgap sensor id
* @val: value (mCelsius) of a new threshold
* @hot: desired threshold to be updated. true if threshold hot, false if
* threshold cold
*
* It will update the required thresholds (hot and cold) for TALERT signal.
* This function can be used to update t_hot or t_cold, depending on @hot value.
* Validates the mCelsius range and update the requested threshold.
* Call this function only if bandgap features HAS(TALERT).
*
* Return: 0 if no error, else corresponding error value.
*/
static int _ti_bandgap_write_threshold(struct ti_bandgap *bgp, int id, int val,
bool hot)
{
struct temp_sensor_data *ts_data;
struct temp_sensor_registers *tsr;
u32 adc_val;
int ret;
ret = ti_bandgap_validate(bgp, id);
if (ret)
goto exit;
if (!TI_BANDGAP_HAS(bgp, TALERT)) {
ret = -ENOTSUPP;
goto exit;
}
ts_data = bgp->conf->sensors[id].ts_data;
tsr = bgp->conf->sensors[id].registers;
if (hot) {
if (val < ts_data->min_temp + ts_data->hyst_val)
ret = -EINVAL;
} else {
if (val > ts_data->max_temp + ts_data->hyst_val)
ret = -EINVAL;
}
if (ret)
goto exit;
ret = ti_bandgap_mcelsius_to_adc(bgp, val, &adc_val);
if (ret < 0)
goto exit;
spin_lock(&bgp->lock);
ret = ti_bandgap_update_alert_threshold(bgp, id, adc_val, hot);
spin_unlock(&bgp->lock);
exit:
return ret;
}
/**
* _ti_bandgap_read_threshold() - helper to read TALERT t_cold or t_hot
* @bgp: struct ti_bandgap pointer
* @id: bandgap sensor id
* @val: value (mCelsius) of a threshold
* @hot: desired threshold to be read. true if threshold hot, false if
* threshold cold
*
* It will fetch the required thresholds (hot and cold) for TALERT signal.
* This function can be used to read t_hot or t_cold, depending on @hot value.
* Call this function only if bandgap features HAS(TALERT).
*
* Return: 0 if no error, -ENOTSUPP if it has no TALERT support, or the
* corresponding error value if some operation fails.
*/
static int _ti_bandgap_read_threshold(struct ti_bandgap *bgp, int id,
int *val, bool hot)
{
struct temp_sensor_registers *tsr;
u32 temp, mask;
int ret = 0;
ret = ti_bandgap_validate(bgp, id);
if (ret)
goto exit;
if (!TI_BANDGAP_HAS(bgp, TALERT)) {
ret = -ENOTSUPP;
goto exit;
}
tsr = bgp->conf->sensors[id].registers;
if (hot)
mask = tsr->threshold_thot_mask;
else
mask = tsr->threshold_tcold_mask;
temp = ti_bandgap_readl(bgp, tsr->bgap_threshold);
temp = (temp & mask) >> __ffs(mask);
ret |= ti_bandgap_adc_to_mcelsius(bgp, temp, &temp);
if (ret) {
dev_err(bgp->dev, "failed to read thot\n");
ret = -EIO;
goto exit;
}
*val = temp;
exit:
return ret;
}
/*** Exposed APIs ***/
/**
* ti_bandgap_read_thot() - reads sensor current thot
* @bgp: pointer to bandgap instance
* @id: sensor id
* @thot: resulting current thot value
*
* Return: 0 on success or the proper error code
*/
int ti_bandgap_read_thot(struct ti_bandgap *bgp, int id, int *thot)
{
return _ti_bandgap_read_threshold(bgp, id, thot, true);
}
/**
* ti_bandgap_write_thot() - sets sensor current thot
* @bgp: pointer to bandgap instance
* @id: sensor id
* @val: desired thot value
*
* Return: 0 on success or the proper error code
*/
int ti_bandgap_write_thot(struct ti_bandgap *bgp, int id, int val)
{
return _ti_bandgap_write_threshold(bgp, id, val, true);
}
/**
* ti_bandgap_read_tcold() - reads sensor current tcold
* @bgp: pointer to bandgap instance
* @id: sensor id
* @tcold: resulting current tcold value
*
* Return: 0 on success or the proper error code
*/
int ti_bandgap_read_tcold(struct ti_bandgap *bgp, int id, int *tcold)
{
return _ti_bandgap_read_threshold(bgp, id, tcold, false);
}
/**
* ti_bandgap_write_tcold() - sets the sensor tcold
* @bgp: pointer to bandgap instance
* @id: sensor id
* @val: desired tcold value
*
* Return: 0 on success or the proper error code
*/
int ti_bandgap_write_tcold(struct ti_bandgap *bgp, int id, int val)
{
return _ti_bandgap_write_threshold(bgp, id, val, false);
}
/**
* ti_bandgap_read_counter() - read the sensor counter
* @bgp: pointer to bandgap instance
* @id: sensor id
* @interval: resulting update interval in miliseconds
*/
static void ti_bandgap_read_counter(struct ti_bandgap *bgp, int id,
int *interval)
{
struct temp_sensor_registers *tsr;
int time;
tsr = bgp->conf->sensors[id].registers;
time = ti_bandgap_readl(bgp, tsr->bgap_counter);
time = (time & tsr->counter_mask) >>
__ffs(tsr->counter_mask);
time = time * 1000 / bgp->clk_rate;
*interval = time;
}
/**
* ti_bandgap_read_counter_delay() - read the sensor counter delay
* @bgp: pointer to bandgap instance
* @id: sensor id
* @interval: resulting update interval in miliseconds
*/
static void ti_bandgap_read_counter_delay(struct ti_bandgap *bgp, int id,
int *interval)
{
struct temp_sensor_registers *tsr;
int reg_val;
tsr = bgp->conf->sensors[id].registers;
reg_val = ti_bandgap_readl(bgp, tsr->bgap_mask_ctrl);
reg_val = (reg_val & tsr->mask_counter_delay_mask) >>
__ffs(tsr->mask_counter_delay_mask);
switch (reg_val) {
case 0:
*interval = 0;
break;
case 1:
*interval = 1;
break;
case 2:
*interval = 10;
break;
case 3:
*interval = 100;
break;
case 4:
*interval = 250;
break;
case 5:
*interval = 500;
break;
default:
dev_warn(bgp->dev, "Wrong counter delay value read from register %X",
reg_val);
}
}
/**
* ti_bandgap_read_update_interval() - read the sensor update interval
* @bgp: pointer to bandgap instance
* @id: sensor id
* @interval: resulting update interval in miliseconds
*
* Return: 0 on success or the proper error code
*/
int ti_bandgap_read_update_interval(struct ti_bandgap *bgp, int id,
int *interval)
{
int ret = 0;
ret = ti_bandgap_validate(bgp, id);
if (ret)
goto exit;
if (!TI_BANDGAP_HAS(bgp, COUNTER) &&
!TI_BANDGAP_HAS(bgp, COUNTER_DELAY)) {
ret = -ENOTSUPP;
goto exit;
}
if (TI_BANDGAP_HAS(bgp, COUNTER)) {
ti_bandgap_read_counter(bgp, id, interval);
goto exit;
}
ti_bandgap_read_counter_delay(bgp, id, interval);
exit:
return ret;
}
/**
* ti_bandgap_write_counter_delay() - set the counter_delay
* @bgp: pointer to bandgap instance
* @id: sensor id
* @interval: desired update interval in miliseconds
*
* Return: 0 on success or the proper error code
*/
static int ti_bandgap_write_counter_delay(struct ti_bandgap *bgp, int id,
u32 interval)
{
int rval;
switch (interval) {
case 0: /* Immediate conversion */
rval = 0x0;
break;
case 1: /* Conversion after ever 1ms */
rval = 0x1;
break;
case 10: /* Conversion after ever 10ms */
rval = 0x2;
break;
case 100: /* Conversion after ever 100ms */
rval = 0x3;
break;
case 250: /* Conversion after ever 250ms */
rval = 0x4;
break;
case 500: /* Conversion after ever 500ms */
rval = 0x5;
break;
default:
dev_warn(bgp->dev, "Delay %d ms is not supported\n", interval);
return -EINVAL;
}
spin_lock(&bgp->lock);
RMW_BITS(bgp, id, bgap_mask_ctrl, mask_counter_delay_mask, rval);
spin_unlock(&bgp->lock);
return 0;
}
/**
* ti_bandgap_write_counter() - set the bandgap sensor counter
* @bgp: pointer to bandgap instance
* @id: sensor id
* @interval: desired update interval in miliseconds
*/
static void ti_bandgap_write_counter(struct ti_bandgap *bgp, int id,
u32 interval)
{
interval = interval * bgp->clk_rate / 1000;
spin_lock(&bgp->lock);
RMW_BITS(bgp, id, bgap_counter, counter_mask, interval);
spin_unlock(&bgp->lock);
}
/**
* ti_bandgap_write_update_interval() - set the update interval
* @bgp: pointer to bandgap instance
* @id: sensor id
* @interval: desired update interval in miliseconds
*
* Return: 0 on success or the proper error code
*/
int ti_bandgap_write_update_interval(struct ti_bandgap *bgp,
int id, u32 interval)
{
int ret = ti_bandgap_validate(bgp, id);
if (ret)
goto exit;
if (!TI_BANDGAP_HAS(bgp, COUNTER) &&
!TI_BANDGAP_HAS(bgp, COUNTER_DELAY)) {
ret = -ENOTSUPP;
goto exit;
}
if (TI_BANDGAP_HAS(bgp, COUNTER)) {
ti_bandgap_write_counter(bgp, id, interval);
goto exit;
}
ret = ti_bandgap_write_counter_delay(bgp, id, interval);
exit:
return ret;
}
/**
* ti_bandgap_read_temperature() - report current temperature
* @bgp: pointer to bandgap instance
* @id: sensor id
* @temperature: resulting temperature
*
* Return: 0 on success or the proper error code
*/
int ti_bandgap_read_temperature(struct ti_bandgap *bgp, int id,
int *temperature)
{
u32 temp;
int ret;
ret = ti_bandgap_validate(bgp, id);
if (ret)
return ret;
spin_lock(&bgp->lock);
temp = ti_bandgap_read_temp(bgp, id);
spin_unlock(&bgp->lock);
ret |= ti_bandgap_adc_to_mcelsius(bgp, temp, &temp);
if (ret)
return -EIO;
*temperature = temp;
return 0;
}
/**
* ti_bandgap_set_sensor_data() - helper function to store thermal
* framework related data.
* @bgp: pointer to bandgap instance
* @id: sensor id
* @data: thermal framework related data to be stored
*
* Return: 0 on success or the proper error code
*/
int ti_bandgap_set_sensor_data(struct ti_bandgap *bgp, int id, void *data)
{
int ret = ti_bandgap_validate(bgp, id);
if (ret)
return ret;
bgp->regval[id].data = data;
return 0;
}
/**
* ti_bandgap_get_sensor_data() - helper function to get thermal
* framework related data.
* @bgp: pointer to bandgap instance
* @id: sensor id
*
* Return: data stored by set function with sensor id on success or NULL
*/
void *ti_bandgap_get_sensor_data(struct ti_bandgap *bgp, int id)
{
int ret = ti_bandgap_validate(bgp, id);
if (ret)
return ERR_PTR(ret);
return bgp->regval[id].data;
}
/*** Helper functions used during device initialization ***/
/**
* ti_bandgap_force_single_read() - executes 1 single ADC conversion
* @bgp: pointer to struct ti_bandgap
* @id: sensor id which it is desired to read 1 temperature
*
* Used to initialize the conversion state machine and set it to a valid
* state. Called during device initialization and context restore events.
*
* Return: 0
*/
static int
ti_bandgap_force_single_read(struct ti_bandgap *bgp, int id)
{
u32 temp = 0, counter = 1000;
/* Select single conversion mode */
if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
RMW_BITS(bgp, id, bgap_mode_ctrl, mode_ctrl_mask, 0);
/* Start of Conversion = 1 */
RMW_BITS(bgp, id, temp_sensor_ctrl, bgap_soc_mask, 1);
/* Wait until DTEMP is updated */
temp = ti_bandgap_read_temp(bgp, id);
while ((temp == 0) && --counter)
temp = ti_bandgap_read_temp(bgp, id);
/* REVISIT: Check correct condition for end of conversion */
/* Start of Conversion = 0 */
RMW_BITS(bgp, id, temp_sensor_ctrl, bgap_soc_mask, 0);
return 0;
}
/**
* ti_bandgap_set_continous_mode() - One time enabling of continuous mode
* @bgp: pointer to struct ti_bandgap
*
* Call this function only if HAS(MODE_CONFIG) is set. As this driver may
* be used for junction temperature monitoring, it is desirable that the
* sensors are operational all the time, so that alerts are generated
* properly.
*
* Return: 0
*/
static int ti_bandgap_set_continuous_mode(struct ti_bandgap *bgp)
{
int i;
for (i = 0; i < bgp->conf->sensor_count; i++) {
/* Perform a single read just before enabling continuous */
ti_bandgap_force_single_read(bgp, i);
RMW_BITS(bgp, i, bgap_mode_ctrl, mode_ctrl_mask, 1);
}
return 0;
}
/**
* ti_bandgap_get_trend() - To fetch the temperature trend of a sensor
* @bgp: pointer to struct ti_bandgap
* @id: id of the individual sensor
* @trend: Pointer to trend.
*
* This function needs to be called to fetch the temperature trend of a
* Particular sensor. The function computes the difference in temperature
* w.r.t time. For the bandgaps with built in history buffer the temperatures
* are read from the buffer and for those without the Buffer -ENOTSUPP is
* returned.
*
* Return: 0 if no error, else return corresponding error. If no
* error then the trend value is passed on to trend parameter
*/
int ti_bandgap_get_trend(struct ti_bandgap *bgp, int id, int *trend)
{
struct temp_sensor_registers *tsr;
u32 temp1, temp2, reg1, reg2;
int t1, t2, interval, ret = 0;
ret = ti_bandgap_validate(bgp, id);
if (ret)
goto exit;
if (!TI_BANDGAP_HAS(bgp, HISTORY_BUFFER) ||
!TI_BANDGAP_HAS(bgp, FREEZE_BIT)) {
ret = -ENOTSUPP;
goto exit;
}
spin_lock(&bgp->lock);
tsr = bgp->conf->sensors[id].registers;
/* Freeze and read the last 2 valid readings */
RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 1);
reg1 = tsr->ctrl_dtemp_1;
reg2 = tsr->ctrl_dtemp_2;
/* read temperature from history buffer */
temp1 = ti_bandgap_readl(bgp, reg1);
temp1 &= tsr->bgap_dtemp_mask;
temp2 = ti_bandgap_readl(bgp, reg2);
temp2 &= tsr->bgap_dtemp_mask;
/* Convert from adc values to mCelsius temperature */
ret = ti_bandgap_adc_to_mcelsius(bgp, temp1, &t1);
if (ret)
goto unfreeze;
ret = ti_bandgap_adc_to_mcelsius(bgp, temp2, &t2);
if (ret)
goto unfreeze;
/* Fetch the update interval */
ret = ti_bandgap_read_update_interval(bgp, id, &interval);
if (ret)
goto unfreeze;
/* Set the interval to 1 ms if bandgap counter delay is not set */
if (interval == 0)
interval = 1;
*trend = (t1 - t2) / interval;
dev_dbg(bgp->dev, "The temperatures are t1 = %d and t2 = %d and trend =%d\n",
t1, t2, *trend);
unfreeze:
RMW_BITS(bgp, id, bgap_mask_ctrl, mask_freeze_mask, 0);
spin_unlock(&bgp->lock);
exit:
return ret;
}
/**
* ti_bandgap_tshut_init() - setup and initialize tshut handling
* @bgp: pointer to struct ti_bandgap
* @pdev: pointer to device struct platform_device
*
* Call this function only in case the bandgap features HAS(TSHUT).
* In this case, the driver needs to handle the TSHUT signal as an IRQ.
* The IRQ is wired as a GPIO, and for this purpose, it is required
* to specify which GPIO line is used. TSHUT IRQ is fired anytime
* one of the bandgap sensors violates the TSHUT high/hot threshold.
* And in that case, the system must go off.
*
* Return: 0 if no error, else error status
*/
static int ti_bandgap_tshut_init(struct ti_bandgap *bgp,
struct platform_device *pdev)
{
int gpio_nr = bgp->tshut_gpio;
int status;
/* Request for gpio_86 line */
status = gpio_request(gpio_nr, "tshut");
if (status < 0) {
dev_err(bgp->dev, "Could not request for TSHUT GPIO:%i\n", 86);
return status;
}
status = gpio_direction_input(gpio_nr);
if (status) {
dev_err(bgp->dev, "Cannot set input TSHUT GPIO %d\n", gpio_nr);
return status;
}
status = request_irq(gpio_to_irq(gpio_nr), ti_bandgap_tshut_irq_handler,
IRQF_TRIGGER_RISING, "tshut", NULL);
if (status) {
gpio_free(gpio_nr);
dev_err(bgp->dev, "request irq failed for TSHUT");
}
return 0;
}
/**
* ti_bandgap_alert_init() - setup and initialize talert handling
* @bgp: pointer to struct ti_bandgap
* @pdev: pointer to device struct platform_device
*
* Call this function only in case the bandgap features HAS(TALERT).
* In this case, the driver needs to handle the TALERT signals as an IRQs.
* TALERT is a normal IRQ and it is fired any time thresholds (hot or cold)
* are violated. In these situation, the driver must reprogram the thresholds,
* accordingly to specified policy.
*
* Return: 0 if no error, else return corresponding error.
*/
static int ti_bandgap_talert_init(struct ti_bandgap *bgp,
struct platform_device *pdev)
{
int ret;
bgp->irq = platform_get_irq(pdev, 0);
if (bgp->irq < 0) {
dev_err(&pdev->dev, "get_irq failed\n");
return bgp->irq;
}
ret = request_threaded_irq(bgp->irq, NULL,
ti_bandgap_talert_irq_handler,
IRQF_TRIGGER_HIGH | IRQF_ONESHOT,
"talert", bgp);
if (ret) {
dev_err(&pdev->dev, "Request threaded irq failed.\n");
return ret;
}
return 0;
}
static const struct of_device_id of_ti_bandgap_match[];
/**
* ti_bandgap_build() - parse DT and setup a struct ti_bandgap
* @pdev: pointer to device struct platform_device
*
* Used to read the device tree properties accordingly to the bandgap
* matching version. Based on bandgap version and its capabilities it
* will build a struct ti_bandgap out of the required DT entries.
*
* Return: valid bandgap structure if successful, else returns ERR_PTR
* return value must be verified with IS_ERR.
*/
static struct ti_bandgap *ti_bandgap_build(struct platform_device *pdev)
{
struct device_node *node = pdev->dev.of_node;
const struct of_device_id *of_id;
struct ti_bandgap *bgp;
struct resource *res;
int i;
/* just for the sake */
if (!node) {
dev_err(&pdev->dev, "no platform information available\n");
return ERR_PTR(-EINVAL);
}
bgp = devm_kzalloc(&pdev->dev, sizeof(*bgp), GFP_KERNEL);
if (!bgp) {
dev_err(&pdev->dev, "Unable to allocate mem for driver ref\n");
return ERR_PTR(-ENOMEM);
}
of_id = of_match_device(of_ti_bandgap_match, &pdev->dev);
if (of_id)
bgp->conf = of_id->data;
/* register shadow for context save and restore */
bgp->regval = devm_kzalloc(&pdev->dev, sizeof(*bgp->regval) *
bgp->conf->sensor_count, GFP_KERNEL);
if (!bgp) {
dev_err(&pdev->dev, "Unable to allocate mem for driver ref\n");
return ERR_PTR(-ENOMEM);
}
i = 0;
do {
void __iomem *chunk;
res = platform_get_resource(pdev, IORESOURCE_MEM, i);
if (!res)
break;
chunk = devm_ioremap_resource(&pdev->dev, res);
if (i == 0)
bgp->base = chunk;
if (IS_ERR(chunk))
return ERR_CAST(chunk);
i++;
} while (res);
if (TI_BANDGAP_HAS(bgp, TSHUT)) {
bgp->tshut_gpio = of_get_gpio(node, 0);
if (!gpio_is_valid(bgp->tshut_gpio)) {
dev_err(&pdev->dev, "invalid gpio for tshut (%d)\n",
bgp->tshut_gpio);
return ERR_PTR(-EINVAL);
}
}
return bgp;
}
/*** Device driver call backs ***/
static
int ti_bandgap_probe(struct platform_device *pdev)
{
struct ti_bandgap *bgp;
int clk_rate, ret = 0, i;
bgp = ti_bandgap_build(pdev);
if (IS_ERR(bgp)) {
dev_err(&pdev->dev, "failed to fetch platform data\n");
return PTR_ERR(bgp);
}
bgp->dev = &pdev->dev;
if (TI_BANDGAP_HAS(bgp, TSHUT)) {
ret = ti_bandgap_tshut_init(bgp, pdev);
if (ret) {
dev_err(&pdev->dev,
"failed to initialize system tshut IRQ\n");
return ret;
}
}
bgp->fclock = clk_get(NULL, bgp->conf->fclock_name);
ret = IS_ERR(bgp->fclock);
if (ret) {
dev_err(&pdev->dev, "failed to request fclock reference\n");
ret = PTR_ERR(bgp->fclock);
goto free_irqs;
}
bgp->div_clk = clk_get(NULL, bgp->conf->div_ck_name);
ret = IS_ERR(bgp->div_clk);
if (ret) {
dev_err(&pdev->dev,
"failed to request div_ts_ck clock ref\n");
ret = PTR_ERR(bgp->div_clk);
goto free_irqs;
}
for (i = 0; i < bgp->conf->sensor_count; i++) {
struct temp_sensor_registers *tsr;
u32 val;
tsr = bgp->conf->sensors[i].registers;
/*
* check if the efuse has a non-zero value if not
* it is an untrimmed sample and the temperatures
* may not be accurate
*/
val = ti_bandgap_readl(bgp, tsr->bgap_efuse);
if (ret || !val)
dev_info(&pdev->dev,
"Non-trimmed BGAP, Temp not accurate\n");
}
clk_rate = clk_round_rate(bgp->div_clk,
bgp->conf->sensors[0].ts_data->max_freq);
if (clk_rate < bgp->conf->sensors[0].ts_data->min_freq ||
clk_rate == 0xffffffff) {
ret = -ENODEV;
dev_err(&pdev->dev, "wrong clock rate (%d)\n", clk_rate);
goto put_clks;
}
ret = clk_set_rate(bgp->div_clk, clk_rate);
if (ret)
dev_err(&pdev->dev, "Cannot re-set clock rate. Continuing\n");
bgp->clk_rate = clk_rate;
if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
clk_prepare_enable(bgp->fclock);
spin_lock_init(&bgp->lock);
bgp->dev = &pdev->dev;
platform_set_drvdata(pdev, bgp);
ti_bandgap_power(bgp, true);
/* Set default counter to 1 for now */
if (TI_BANDGAP_HAS(bgp, COUNTER))
for (i = 0; i < bgp->conf->sensor_count; i++)
RMW_BITS(bgp, i, bgap_counter, counter_mask, 1);
/* Set default thresholds for alert and shutdown */
for (i = 0; i < bgp->conf->sensor_count; i++) {
struct temp_sensor_data *ts_data;
ts_data = bgp->conf->sensors[i].ts_data;
if (TI_BANDGAP_HAS(bgp, TALERT)) {
/* Set initial Talert thresholds */
RMW_BITS(bgp, i, bgap_threshold,
threshold_tcold_mask, ts_data->t_cold);
RMW_BITS(bgp, i, bgap_threshold,
threshold_thot_mask, ts_data->t_hot);
/* Enable the alert events */
RMW_BITS(bgp, i, bgap_mask_ctrl, mask_hot_mask, 1);
RMW_BITS(bgp, i, bgap_mask_ctrl, mask_cold_mask, 1);
}
if (TI_BANDGAP_HAS(bgp, TSHUT_CONFIG)) {
/* Set initial Tshut thresholds */
RMW_BITS(bgp, i, tshut_threshold,
tshut_hot_mask, ts_data->tshut_hot);
RMW_BITS(bgp, i, tshut_threshold,
tshut_cold_mask, ts_data->tshut_cold);
}
}
if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
ti_bandgap_set_continuous_mode(bgp);
/* Set .250 seconds time as default counter */
if (TI_BANDGAP_HAS(bgp, COUNTER))
for (i = 0; i < bgp->conf->sensor_count; i++)
RMW_BITS(bgp, i, bgap_counter, counter_mask,
bgp->clk_rate / 4);
/* Every thing is good? Then expose the sensors */
for (i = 0; i < bgp->conf->sensor_count; i++) {
char *domain;
if (bgp->conf->sensors[i].register_cooling) {
ret = bgp->conf->sensors[i].register_cooling(bgp, i);
if (ret)
goto remove_sensors;
}
if (bgp->conf->expose_sensor) {
domain = bgp->conf->sensors[i].domain;
ret = bgp->conf->expose_sensor(bgp, i, domain);
if (ret)
goto remove_last_cooling;
}
}
/*
* Enable the Interrupts once everything is set. Otherwise irq handler
* might be called as soon as it is enabled where as rest of framework
* is still getting initialised.
*/
if (TI_BANDGAP_HAS(bgp, TALERT)) {
ret = ti_bandgap_talert_init(bgp, pdev);
if (ret) {
dev_err(&pdev->dev, "failed to initialize Talert IRQ\n");
i = bgp->conf->sensor_count;
goto disable_clk;
}
}
return 0;
remove_last_cooling:
if (bgp->conf->sensors[i].unregister_cooling)
bgp->conf->sensors[i].unregister_cooling(bgp, i);
remove_sensors:
for (i--; i >= 0; i--) {
if (bgp->conf->sensors[i].unregister_cooling)
bgp->conf->sensors[i].unregister_cooling(bgp, i);
if (bgp->conf->remove_sensor)
bgp->conf->remove_sensor(bgp, i);
}
ti_bandgap_power(bgp, false);
disable_clk:
if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
clk_disable_unprepare(bgp->fclock);
put_clks:
clk_put(bgp->fclock);
clk_put(bgp->div_clk);
free_irqs:
if (TI_BANDGAP_HAS(bgp, TSHUT)) {
free_irq(gpio_to_irq(bgp->tshut_gpio), NULL);
gpio_free(bgp->tshut_gpio);
}
return ret;
}
static
int ti_bandgap_remove(struct platform_device *pdev)
{
struct ti_bandgap *bgp = platform_get_drvdata(pdev);
int i;
/* First thing is to remove sensor interfaces */
for (i = 0; i < bgp->conf->sensor_count; i++) {
if (bgp->conf->sensors[i].unregister_cooling)
bgp->conf->sensors[i].unregister_cooling(bgp, i);
if (bgp->conf->remove_sensor)
bgp->conf->remove_sensor(bgp, i);
}
ti_bandgap_power(bgp, false);
if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
clk_disable_unprepare(bgp->fclock);
clk_put(bgp->fclock);
clk_put(bgp->div_clk);
if (TI_BANDGAP_HAS(bgp, TALERT))
free_irq(bgp->irq, bgp);
if (TI_BANDGAP_HAS(bgp, TSHUT)) {
free_irq(gpio_to_irq(bgp->tshut_gpio), NULL);
gpio_free(bgp->tshut_gpio);
}
return 0;
}
#ifdef CONFIG_PM
static int ti_bandgap_save_ctxt(struct ti_bandgap *bgp)
{
int i;
for (i = 0; i < bgp->conf->sensor_count; i++) {
struct temp_sensor_registers *tsr;
struct temp_sensor_regval *rval;
rval = &bgp->regval[i];
tsr = bgp->conf->sensors[i].registers;
if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
rval->bg_mode_ctrl = ti_bandgap_readl(bgp,
tsr->bgap_mode_ctrl);
if (TI_BANDGAP_HAS(bgp, COUNTER))
rval->bg_counter = ti_bandgap_readl(bgp,
tsr->bgap_counter);
if (TI_BANDGAP_HAS(bgp, TALERT)) {
rval->bg_threshold = ti_bandgap_readl(bgp,
tsr->bgap_threshold);
rval->bg_ctrl = ti_bandgap_readl(bgp,
tsr->bgap_mask_ctrl);
}
if (TI_BANDGAP_HAS(bgp, TSHUT_CONFIG))
rval->tshut_threshold = ti_bandgap_readl(bgp,
tsr->tshut_threshold);
}
return 0;
}
static int ti_bandgap_restore_ctxt(struct ti_bandgap *bgp)
{
int i;
for (i = 0; i < bgp->conf->sensor_count; i++) {
struct temp_sensor_registers *tsr;
struct temp_sensor_regval *rval;
u32 val = 0;
rval = &bgp->regval[i];
tsr = bgp->conf->sensors[i].registers;
if (TI_BANDGAP_HAS(bgp, COUNTER))
val = ti_bandgap_readl(bgp, tsr->bgap_counter);
if (TI_BANDGAP_HAS(bgp, TSHUT_CONFIG))
ti_bandgap_writel(bgp, rval->tshut_threshold,
tsr->tshut_threshold);
/* Force immediate temperature measurement and update
* of the DTEMP field
*/
ti_bandgap_force_single_read(bgp, i);
if (TI_BANDGAP_HAS(bgp, COUNTER))
ti_bandgap_writel(bgp, rval->bg_counter,
tsr->bgap_counter);
if (TI_BANDGAP_HAS(bgp, MODE_CONFIG))
ti_bandgap_writel(bgp, rval->bg_mode_ctrl,
tsr->bgap_mode_ctrl);
if (TI_BANDGAP_HAS(bgp, TALERT)) {
ti_bandgap_writel(bgp, rval->bg_threshold,
tsr->bgap_threshold);
ti_bandgap_writel(bgp, rval->bg_ctrl,
tsr->bgap_mask_ctrl);
}
}
return 0;
}
static int ti_bandgap_suspend(struct device *dev)
{
struct ti_bandgap *bgp = dev_get_drvdata(dev);
int err;
err = ti_bandgap_save_ctxt(bgp);
ti_bandgap_power(bgp, false);
if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
clk_disable_unprepare(bgp->fclock);
return err;
}
static int ti_bandgap_resume(struct device *dev)
{
struct ti_bandgap *bgp = dev_get_drvdata(dev);
if (TI_BANDGAP_HAS(bgp, CLK_CTRL))
clk_prepare_enable(bgp->fclock);
ti_bandgap_power(bgp, true);
return ti_bandgap_restore_ctxt(bgp);
}
static const struct dev_pm_ops ti_bandgap_dev_pm_ops = {
SET_SYSTEM_SLEEP_PM_OPS(ti_bandgap_suspend,
ti_bandgap_resume)
};
#define DEV_PM_OPS (&ti_bandgap_dev_pm_ops)
#else
#define DEV_PM_OPS NULL
#endif
static const struct of_device_id of_ti_bandgap_match[] = {
#ifdef CONFIG_OMAP4_THERMAL
{
.compatible = "ti,omap4430-bandgap",
.data = (void *)&omap4430_data,
},
{
.compatible = "ti,omap4460-bandgap",
.data = (void *)&omap4460_data,
},
{
.compatible = "ti,omap4470-bandgap",
.data = (void *)&omap4470_data,
},
#endif
#ifdef CONFIG_OMAP5_THERMAL
{
.compatible = "ti,omap5430-bandgap",
.data = (void *)&omap5430_data,
},
#endif
#ifdef CONFIG_DRA752_THERMAL
{
.compatible = "ti,dra752-bandgap",
.data = (void *)&dra752_data,
},
#endif
/* Sentinel */
{ },
};
MODULE_DEVICE_TABLE(of, of_ti_bandgap_match);
static struct platform_driver ti_bandgap_sensor_driver = {
.probe = ti_bandgap_probe,
.remove = ti_bandgap_remove,
.driver = {
.name = "ti-soc-thermal",
.pm = DEV_PM_OPS,
.of_match_table = of_ti_bandgap_match,
},
};
module_platform_driver(ti_bandgap_sensor_driver);
MODULE_DESCRIPTION("OMAP4+ bandgap temperature sensor driver");
MODULE_LICENSE("GPL v2");
MODULE_ALIAS("platform:ti-soc-thermal");
MODULE_AUTHOR("Texas Instrument Inc.");