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kernel/drivers/iio/adc/twl4030-madc.c

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/*
*
* TWL4030 MADC module driver-This driver monitors the real time
* conversion of analog signals like battery temperature,
* battery type, battery level etc.
*
* Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
* J Keerthy <j-keerthy@ti.com>
*
* Based on twl4030-madc.c
* Copyright (C) 2008 Nokia Corporation
* Mikko Ylinen <mikko.k.ylinen@nokia.com>
*
* Amit Kucheria <amit.kucheria@canonical.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/device.h>
#include <linux/interrupt.h>
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
#include <linux/mfd/twl.h>
#include <linux/module.h>
#include <linux/stddef.h>
#include <linux/mutex.h>
#include <linux/bitops.h>
#include <linux/jiffies.h>
#include <linux/types.h>
#include <linux/gfp.h>
#include <linux/err.h>
#include <linux/regulator/consumer.h>
#include <linux/iio/iio.h>
#define TWL4030_MADC_MAX_CHANNELS 16
#define TWL4030_MADC_CTRL1 0x00
#define TWL4030_MADC_CTRL2 0x01
#define TWL4030_MADC_RTSELECT_LSB 0x02
#define TWL4030_MADC_SW1SELECT_LSB 0x06
#define TWL4030_MADC_SW2SELECT_LSB 0x0A
#define TWL4030_MADC_RTAVERAGE_LSB 0x04
#define TWL4030_MADC_SW1AVERAGE_LSB 0x08
#define TWL4030_MADC_SW2AVERAGE_LSB 0x0C
#define TWL4030_MADC_CTRL_SW1 0x12
#define TWL4030_MADC_CTRL_SW2 0x13
#define TWL4030_MADC_RTCH0_LSB 0x17
#define TWL4030_MADC_GPCH0_LSB 0x37
#define TWL4030_MADC_MADCON (1 << 0) /* MADC power on */
#define TWL4030_MADC_BUSY (1 << 0) /* MADC busy */
/* MADC conversion completion */
#define TWL4030_MADC_EOC_SW (1 << 1)
/* MADC SWx start conversion */
#define TWL4030_MADC_SW_START (1 << 5)
#define TWL4030_MADC_ADCIN0 (1 << 0)
#define TWL4030_MADC_ADCIN1 (1 << 1)
#define TWL4030_MADC_ADCIN2 (1 << 2)
#define TWL4030_MADC_ADCIN3 (1 << 3)
#define TWL4030_MADC_ADCIN4 (1 << 4)
#define TWL4030_MADC_ADCIN5 (1 << 5)
#define TWL4030_MADC_ADCIN6 (1 << 6)
#define TWL4030_MADC_ADCIN7 (1 << 7)
#define TWL4030_MADC_ADCIN8 (1 << 8)
#define TWL4030_MADC_ADCIN9 (1 << 9)
#define TWL4030_MADC_ADCIN10 (1 << 10)
#define TWL4030_MADC_ADCIN11 (1 << 11)
#define TWL4030_MADC_ADCIN12 (1 << 12)
#define TWL4030_MADC_ADCIN13 (1 << 13)
#define TWL4030_MADC_ADCIN14 (1 << 14)
#define TWL4030_MADC_ADCIN15 (1 << 15)
/* Fixed channels */
#define TWL4030_MADC_BTEMP TWL4030_MADC_ADCIN1
#define TWL4030_MADC_VBUS TWL4030_MADC_ADCIN8
#define TWL4030_MADC_VBKB TWL4030_MADC_ADCIN9
#define TWL4030_MADC_ICHG TWL4030_MADC_ADCIN10
#define TWL4030_MADC_VCHG TWL4030_MADC_ADCIN11
#define TWL4030_MADC_VBAT TWL4030_MADC_ADCIN12
/* Step size and prescaler ratio */
#define TEMP_STEP_SIZE 147
#define TEMP_PSR_R 100
#define CURR_STEP_SIZE 147
#define CURR_PSR_R1 44
#define CURR_PSR_R2 88
#define TWL4030_BCI_BCICTL1 0x23
#define TWL4030_BCI_CGAIN 0x020
#define TWL4030_BCI_MESBAT (1 << 1)
#define TWL4030_BCI_TYPEN (1 << 4)
#define TWL4030_BCI_ITHEN (1 << 3)
#define REG_BCICTL2 0x024
#define TWL4030_BCI_ITHSENS 0x007
/* Register and bits for GPBR1 register */
#define TWL4030_REG_GPBR1 0x0c
#define TWL4030_GPBR1_MADC_HFCLK_EN (1 << 7)
#define TWL4030_USB_SEL_MADC_MCPC (1<<3)
#define TWL4030_USB_CARKIT_ANA_CTRL 0xBB
struct twl4030_madc_conversion_method {
u8 sel;
u8 avg;
u8 rbase;
u8 ctrl;
};
/**
* struct twl4030_madc_request - madc request packet for channel conversion
* @channels: 16 bit bitmap for individual channels
* @do_avg: sample the input channel for 4 consecutive cycles
* @method: RT, SW1, SW2
* @type: Polling or interrupt based method
* @active: Flag if request is active
* @result_pending: Flag from irq handler, that result is ready
* @raw: Return raw value, do not convert it
* @rbuf: Result buffer
*/
struct twl4030_madc_request {
unsigned long channels;
bool do_avg;
u16 method;
u16 type;
bool active;
bool result_pending;
bool raw;
int rbuf[TWL4030_MADC_MAX_CHANNELS];
};
enum conversion_methods {
TWL4030_MADC_RT,
TWL4030_MADC_SW1,
TWL4030_MADC_SW2,
TWL4030_MADC_NUM_METHODS
};
enum sample_type {
TWL4030_MADC_WAIT,
TWL4030_MADC_IRQ_ONESHOT,
TWL4030_MADC_IRQ_REARM
};
/**
* struct twl4030_madc_data - a container for madc info
* @dev: Pointer to device structure for madc
* @lock: Mutex protecting this data structure
* @regulator: Pointer to bias regulator for madc
* @requests: Array of request struct corresponding to SW1, SW2 and RT
* @use_second_irq: IRQ selection (main or co-processor)
* @imr: Interrupt mask register of MADC
* @isr: Interrupt status register of MADC
*/
struct twl4030_madc_data {
struct device *dev;
struct mutex lock; /* mutex protecting this data structure */
struct regulator *usb3v1;
struct twl4030_madc_request requests[TWL4030_MADC_NUM_METHODS];
bool use_second_irq;
u8 imr;
u8 isr;
};
static int twl4030_madc_conversion(struct twl4030_madc_request *req);
static int twl4030_madc_read(struct iio_dev *iio_dev,
const struct iio_chan_spec *chan,
int *val, int *val2, long mask)
{
struct twl4030_madc_data *madc = iio_priv(iio_dev);
struct twl4030_madc_request req;
int ret;
req.method = madc->use_second_irq ? TWL4030_MADC_SW2 : TWL4030_MADC_SW1;
req.channels = BIT(chan->channel);
req.active = false;
req.type = TWL4030_MADC_WAIT;
req.raw = !(mask == IIO_CHAN_INFO_PROCESSED);
req.do_avg = (mask == IIO_CHAN_INFO_AVERAGE_RAW);
ret = twl4030_madc_conversion(&req);
if (ret < 0)
return ret;
*val = req.rbuf[chan->channel];
return IIO_VAL_INT;
}
static const struct iio_info twl4030_madc_iio_info = {
.read_raw = &twl4030_madc_read,
};
#define TWL4030_ADC_CHANNEL(_channel, _type, _name) { \
.type = _type, \
.channel = _channel, \
.info_mask_separate = BIT(IIO_CHAN_INFO_RAW) | \
BIT(IIO_CHAN_INFO_AVERAGE_RAW) | \
BIT(IIO_CHAN_INFO_PROCESSED), \
.datasheet_name = _name, \
.indexed = 1, \
}
static const struct iio_chan_spec twl4030_madc_iio_channels[] = {
TWL4030_ADC_CHANNEL(0, IIO_VOLTAGE, "ADCIN0"),
TWL4030_ADC_CHANNEL(1, IIO_TEMP, "ADCIN1"),
TWL4030_ADC_CHANNEL(2, IIO_VOLTAGE, "ADCIN2"),
TWL4030_ADC_CHANNEL(3, IIO_VOLTAGE, "ADCIN3"),
TWL4030_ADC_CHANNEL(4, IIO_VOLTAGE, "ADCIN4"),
TWL4030_ADC_CHANNEL(5, IIO_VOLTAGE, "ADCIN5"),
TWL4030_ADC_CHANNEL(6, IIO_VOLTAGE, "ADCIN6"),
TWL4030_ADC_CHANNEL(7, IIO_VOLTAGE, "ADCIN7"),
TWL4030_ADC_CHANNEL(8, IIO_VOLTAGE, "ADCIN8"),
TWL4030_ADC_CHANNEL(9, IIO_VOLTAGE, "ADCIN9"),
TWL4030_ADC_CHANNEL(10, IIO_CURRENT, "ADCIN10"),
TWL4030_ADC_CHANNEL(11, IIO_VOLTAGE, "ADCIN11"),
TWL4030_ADC_CHANNEL(12, IIO_VOLTAGE, "ADCIN12"),
TWL4030_ADC_CHANNEL(13, IIO_VOLTAGE, "ADCIN13"),
TWL4030_ADC_CHANNEL(14, IIO_VOLTAGE, "ADCIN14"),
TWL4030_ADC_CHANNEL(15, IIO_VOLTAGE, "ADCIN15"),
};
static struct twl4030_madc_data *twl4030_madc;
struct twl4030_prescale_divider_ratios {
s16 numerator;
s16 denominator;
};
static const struct twl4030_prescale_divider_ratios
twl4030_divider_ratios[16] = {
{1, 1}, /* CHANNEL 0 No Prescaler */
{1, 1}, /* CHANNEL 1 No Prescaler */
{6, 10}, /* CHANNEL 2 */
{6, 10}, /* CHANNEL 3 */
{6, 10}, /* CHANNEL 4 */
{6, 10}, /* CHANNEL 5 */
{6, 10}, /* CHANNEL 6 */
{6, 10}, /* CHANNEL 7 */
{3, 14}, /* CHANNEL 8 */
{1, 3}, /* CHANNEL 9 */
{1, 1}, /* CHANNEL 10 No Prescaler */
{15, 100}, /* CHANNEL 11 */
{1, 4}, /* CHANNEL 12 */
{1, 1}, /* CHANNEL 13 Reserved channels */
{1, 1}, /* CHANNEL 14 Reseved channels */
{5, 11}, /* CHANNEL 15 */
};
/* Conversion table from -3 to 55 degrees Celcius */
static int twl4030_therm_tbl[] = {
30800, 29500, 28300, 27100,
26000, 24900, 23900, 22900, 22000, 21100, 20300, 19400, 18700,
17900, 17200, 16500, 15900, 15300, 14700, 14100, 13600, 13100,
12600, 12100, 11600, 11200, 10800, 10400, 10000, 9630, 9280,
8950, 8620, 8310, 8020, 7730, 7460, 7200, 6950, 6710,
6470, 6250, 6040, 5830, 5640, 5450, 5260, 5090, 4920,
4760, 4600, 4450, 4310, 4170, 4040, 3910, 3790, 3670,
3550
};
/*
* Structure containing the registers
* of different conversion methods supported by MADC.
* Hardware or RT real time conversion request initiated by external host
* processor for RT Signal conversions.
* External host processors can also request for non RT conversions
* SW1 and SW2 software conversions also called asynchronous or GPC request.
*/
static
const struct twl4030_madc_conversion_method twl4030_conversion_methods[] = {
[TWL4030_MADC_RT] = {
.sel = TWL4030_MADC_RTSELECT_LSB,
.avg = TWL4030_MADC_RTAVERAGE_LSB,
.rbase = TWL4030_MADC_RTCH0_LSB,
},
[TWL4030_MADC_SW1] = {
.sel = TWL4030_MADC_SW1SELECT_LSB,
.avg = TWL4030_MADC_SW1AVERAGE_LSB,
.rbase = TWL4030_MADC_GPCH0_LSB,
.ctrl = TWL4030_MADC_CTRL_SW1,
},
[TWL4030_MADC_SW2] = {
.sel = TWL4030_MADC_SW2SELECT_LSB,
.avg = TWL4030_MADC_SW2AVERAGE_LSB,
.rbase = TWL4030_MADC_GPCH0_LSB,
.ctrl = TWL4030_MADC_CTRL_SW2,
},
};
/**
* twl4030_madc_channel_raw_read() - Function to read a particular channel value
* @madc: pointer to struct twl4030_madc_data
* @reg: lsb of ADC Channel
*
* Return: 0 on success, an error code otherwise.
*/
static int twl4030_madc_channel_raw_read(struct twl4030_madc_data *madc, u8 reg)
{
u16 val;
int ret;
/*
* For each ADC channel, we have MSB and LSB register pair. MSB address
* is always LSB address+1. reg parameter is the address of LSB register
*/
ret = twl_i2c_read_u16(TWL4030_MODULE_MADC, &val, reg);
if (ret) {
dev_err(madc->dev, "unable to read register 0x%X\n", reg);
return ret;
}
return (int)(val >> 6);
}
/*
* Return battery temperature in degrees Celsius
* Or < 0 on failure.
*/
static int twl4030battery_temperature(int raw_volt)
{
u8 val;
int temp, curr, volt, res, ret;
volt = (raw_volt * TEMP_STEP_SIZE) / TEMP_PSR_R;
/* Getting and calculating the supply current in micro amperes */
ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, &val,
REG_BCICTL2);
if (ret < 0)
return ret;
curr = ((val & TWL4030_BCI_ITHSENS) + 1) * 10;
/* Getting and calculating the thermistor resistance in ohms */
res = volt * 1000 / curr;
/* calculating temperature */
for (temp = 58; temp >= 0; temp--) {
int actual = twl4030_therm_tbl[temp];
if ((actual - res) >= 0)
break;
}
return temp + 1;
}
static int twl4030battery_current(int raw_volt)
{
int ret;
u8 val;
ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE, &val,
TWL4030_BCI_BCICTL1);
if (ret)
return ret;
if (val & TWL4030_BCI_CGAIN) /* slope of 0.44 mV/mA */
return (raw_volt * CURR_STEP_SIZE) / CURR_PSR_R1;
else /* slope of 0.88 mV/mA */
return (raw_volt * CURR_STEP_SIZE) / CURR_PSR_R2;
}
/*
* Function to read channel values
* @madc - pointer to twl4030_madc_data struct
* @reg_base - Base address of the first channel
* @Channels - 16 bit bitmap. If the bit is set, channel's value is read
* @buf - The channel values are stored here. if read fails error
* @raw - Return raw values without conversion
* value is stored
* Returns the number of successfully read channels.
*/
static int twl4030_madc_read_channels(struct twl4030_madc_data *madc,
u8 reg_base, unsigned
long channels, int *buf,
bool raw)
{
int count = 0;
int i;
u8 reg;
for_each_set_bit(i, &channels, TWL4030_MADC_MAX_CHANNELS) {
reg = reg_base + (2 * i);
buf[i] = twl4030_madc_channel_raw_read(madc, reg);
if (buf[i] < 0) {
dev_err(madc->dev, "Unable to read register 0x%X\n",
reg);
return buf[i];
}
if (raw) {
count++;
continue;
}
switch (i) {
case 10:
buf[i] = twl4030battery_current(buf[i]);
if (buf[i] < 0) {
dev_err(madc->dev, "err reading current\n");
return buf[i];
} else {
count++;
buf[i] = buf[i] - 750;
}
break;
case 1:
buf[i] = twl4030battery_temperature(buf[i]);
if (buf[i] < 0) {
dev_err(madc->dev, "err reading temperature\n");
return buf[i];
} else {
buf[i] -= 3;
count++;
}
break;
default:
count++;
/* Analog Input (V) = conv_result * step_size / R
* conv_result = decimal value of 10-bit conversion
* result
* step size = 1.5 / (2 ^ 10 -1)
* R = Prescaler ratio for input channels.
* Result given in mV hence multiplied by 1000.
*/
buf[i] = (buf[i] * 3 * 1000 *
twl4030_divider_ratios[i].denominator)
/ (2 * 1023 *
twl4030_divider_ratios[i].numerator);
}
}
return count;
}
/*
* Disables irq.
* @madc - pointer to twl4030_madc_data struct
* @id - irq number to be disabled
* can take one of TWL4030_MADC_RT, TWL4030_MADC_SW1, TWL4030_MADC_SW2
* corresponding to RT, SW1, SW2 conversion requests.
* Returns error if i2c read/write fails.
*/
static int twl4030_madc_disable_irq(struct twl4030_madc_data *madc, u8 id)
{
u8 val;
int ret;
ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &val, madc->imr);
if (ret) {
dev_err(madc->dev, "unable to read imr register 0x%X\n",
madc->imr);
return ret;
}
val |= (1 << id);
ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, val, madc->imr);
if (ret) {
dev_err(madc->dev,
"unable to write imr register 0x%X\n", madc->imr);
return ret;
}
return 0;
}
static irqreturn_t twl4030_madc_threaded_irq_handler(int irq, void *_madc)
{
struct twl4030_madc_data *madc = _madc;
const struct twl4030_madc_conversion_method *method;
u8 isr_val, imr_val;
int i, len, ret;
struct twl4030_madc_request *r;
mutex_lock(&madc->lock);
ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &isr_val, madc->isr);
if (ret) {
dev_err(madc->dev, "unable to read isr register 0x%X\n",
madc->isr);
goto err_i2c;
}
ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &imr_val, madc->imr);
if (ret) {
dev_err(madc->dev, "unable to read imr register 0x%X\n",
madc->imr);
goto err_i2c;
}
isr_val &= ~imr_val;
for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) {
if (!(isr_val & (1 << i)))
continue;
ret = twl4030_madc_disable_irq(madc, i);
if (ret < 0)
dev_dbg(madc->dev, "Disable interrupt failed %d\n", i);
madc->requests[i].result_pending = 1;
}
for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) {
r = &madc->requests[i];
/* No pending results for this method, move to next one */
if (!r->result_pending)
continue;
method = &twl4030_conversion_methods[r->method];
/* Read results */
len = twl4030_madc_read_channels(madc, method->rbase,
r->channels, r->rbuf, r->raw);
/* Free request */
r->result_pending = 0;
r->active = 0;
}
mutex_unlock(&madc->lock);
return IRQ_HANDLED;
err_i2c:
/*
* In case of error check whichever request is active
* and service the same.
*/
for (i = 0; i < TWL4030_MADC_NUM_METHODS; i++) {
r = &madc->requests[i];
if (r->active == 0)
continue;
method = &twl4030_conversion_methods[r->method];
/* Read results */
len = twl4030_madc_read_channels(madc, method->rbase,
r->channels, r->rbuf, r->raw);
/* Free request */
r->result_pending = 0;
r->active = 0;
}
mutex_unlock(&madc->lock);
return IRQ_HANDLED;
}
/*
* Function which enables the madc conversion
* by writing to the control register.
* @madc - pointer to twl4030_madc_data struct
* @conv_method - can be TWL4030_MADC_RT, TWL4030_MADC_SW2, TWL4030_MADC_SW1
* corresponding to RT SW1 or SW2 conversion methods.
* Returns 0 if succeeds else a negative error value
*/
static int twl4030_madc_start_conversion(struct twl4030_madc_data *madc,
int conv_method)
{
const struct twl4030_madc_conversion_method *method;
int ret = 0;
if (conv_method != TWL4030_MADC_SW1 && conv_method != TWL4030_MADC_SW2)
return -ENOTSUPP;
method = &twl4030_conversion_methods[conv_method];
ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, TWL4030_MADC_SW_START,
method->ctrl);
if (ret) {
dev_err(madc->dev, "unable to write ctrl register 0x%X\n",
method->ctrl);
return ret;
}
return 0;
}
/*
* Function that waits for conversion to be ready
* @madc - pointer to twl4030_madc_data struct
* @timeout_ms - timeout value in milliseconds
* @status_reg - ctrl register
* returns 0 if succeeds else a negative error value
*/
static int twl4030_madc_wait_conversion_ready(struct twl4030_madc_data *madc,
unsigned int timeout_ms,
u8 status_reg)
{
unsigned long timeout;
int ret;
timeout = jiffies + msecs_to_jiffies(timeout_ms);
do {
u8 reg;
ret = twl_i2c_read_u8(TWL4030_MODULE_MADC, &reg, status_reg);
if (ret) {
dev_err(madc->dev,
"unable to read status register 0x%X\n",
status_reg);
return ret;
}
if (!(reg & TWL4030_MADC_BUSY) && (reg & TWL4030_MADC_EOC_SW))
return 0;
usleep_range(500, 2000);
} while (!time_after(jiffies, timeout));
dev_err(madc->dev, "conversion timeout!\n");
return -EAGAIN;
}
/*
* An exported function which can be called from other kernel drivers.
* @req twl4030_madc_request structure
* req->rbuf will be filled with read values of channels based on the
* channel index. If a particular channel reading fails there will
* be a negative error value in the corresponding array element.
* returns 0 if succeeds else error value
*/
static int twl4030_madc_conversion(struct twl4030_madc_request *req)
{
const struct twl4030_madc_conversion_method *method;
int ret;
if (!req || !twl4030_madc)
return -EINVAL;
mutex_lock(&twl4030_madc->lock);
if (req->method < TWL4030_MADC_RT || req->method > TWL4030_MADC_SW2) {
ret = -EINVAL;
goto out;
}
/* Do we have a conversion request ongoing */
if (twl4030_madc->requests[req->method].active) {
ret = -EBUSY;
goto out;
}
method = &twl4030_conversion_methods[req->method];
/* Select channels to be converted */
ret = twl_i2c_write_u16(TWL4030_MODULE_MADC, req->channels, method->sel);
if (ret) {
dev_err(twl4030_madc->dev,
"unable to write sel register 0x%X\n", method->sel);
goto out;
}
/* Select averaging for all channels if do_avg is set */
if (req->do_avg) {
ret = twl_i2c_write_u16(TWL4030_MODULE_MADC, req->channels,
method->avg);
if (ret) {
dev_err(twl4030_madc->dev,
"unable to write avg register 0x%X\n",
method->avg);
goto out;
}
}
/* With RT method we should not be here anymore */
if (req->method == TWL4030_MADC_RT) {
ret = -EINVAL;
goto out;
}
ret = twl4030_madc_start_conversion(twl4030_madc, req->method);
if (ret < 0)
goto out;
twl4030_madc->requests[req->method].active = 1;
/* Wait until conversion is ready (ctrl register returns EOC) */
ret = twl4030_madc_wait_conversion_ready(twl4030_madc, 5, method->ctrl);
if (ret) {
twl4030_madc->requests[req->method].active = 0;
goto out;
}
ret = twl4030_madc_read_channels(twl4030_madc, method->rbase,
req->channels, req->rbuf, req->raw);
twl4030_madc->requests[req->method].active = 0;
out:
mutex_unlock(&twl4030_madc->lock);
return ret;
}
/**
* twl4030_madc_set_current_generator() - setup bias current
*
* @madc: pointer to twl4030_madc_data struct
* @chan: can be one of the two values:
* 0 - Enables bias current for main battery type reading
* 1 - Enables bias current for main battery temperature sensing
* @on: enable or disable chan.
*
* Function to enable or disable bias current for
* main battery type reading or temperature sensing
*/
static int twl4030_madc_set_current_generator(struct twl4030_madc_data *madc,
int chan, int on)
{
int ret;
int regmask;
u8 regval;
ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE,
&regval, TWL4030_BCI_BCICTL1);
if (ret) {
dev_err(madc->dev, "unable to read BCICTL1 reg 0x%X",
TWL4030_BCI_BCICTL1);
return ret;
}
regmask = chan ? TWL4030_BCI_ITHEN : TWL4030_BCI_TYPEN;
if (on)
regval |= regmask;
else
regval &= ~regmask;
ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE,
regval, TWL4030_BCI_BCICTL1);
if (ret) {
dev_err(madc->dev, "unable to write BCICTL1 reg 0x%X\n",
TWL4030_BCI_BCICTL1);
return ret;
}
return 0;
}
/*
* Function that sets MADC software power on bit to enable MADC
* @madc - pointer to twl4030_madc_data struct
* @on - Enable or disable MADC software power on bit.
* returns error if i2c read/write fails else 0
*/
static int twl4030_madc_set_power(struct twl4030_madc_data *madc, int on)
{
u8 regval;
int ret;
ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE,
&regval, TWL4030_MADC_CTRL1);
if (ret) {
dev_err(madc->dev, "unable to read madc ctrl1 reg 0x%X\n",
TWL4030_MADC_CTRL1);
return ret;
}
if (on)
regval |= TWL4030_MADC_MADCON;
else
regval &= ~TWL4030_MADC_MADCON;
ret = twl_i2c_write_u8(TWL4030_MODULE_MADC, regval, TWL4030_MADC_CTRL1);
if (ret) {
dev_err(madc->dev, "unable to write madc ctrl1 reg 0x%X\n",
TWL4030_MADC_CTRL1);
return ret;
}
return 0;
}
/*
* Initialize MADC and request for threaded irq
*/
static int twl4030_madc_probe(struct platform_device *pdev)
{
struct twl4030_madc_data *madc;
struct twl4030_madc_platform_data *pdata = dev_get_platdata(&pdev->dev);
struct device_node *np = pdev->dev.of_node;
int irq, ret;
u8 regval;
struct iio_dev *iio_dev = NULL;
if (!pdata && !np) {
dev_err(&pdev->dev, "neither platform data nor Device Tree node available\n");
return -EINVAL;
}
iio_dev = devm_iio_device_alloc(&pdev->dev, sizeof(*madc));
if (!iio_dev) {
dev_err(&pdev->dev, "failed allocating iio device\n");
return -ENOMEM;
}
madc = iio_priv(iio_dev);
madc->dev = &pdev->dev;
iio_dev->name = dev_name(&pdev->dev);
iio_dev->dev.parent = &pdev->dev;
iio_dev->dev.of_node = pdev->dev.of_node;
iio_dev->info = &twl4030_madc_iio_info;
iio_dev->modes = INDIO_DIRECT_MODE;
iio_dev->channels = twl4030_madc_iio_channels;
iio_dev->num_channels = ARRAY_SIZE(twl4030_madc_iio_channels);
/*
* Phoenix provides 2 interrupt lines. The first one is connected to
* the OMAP. The other one can be connected to the other processor such
* as modem. Hence two separate ISR and IMR registers.
*/
if (pdata)
madc->use_second_irq = (pdata->irq_line != 1);
else
madc->use_second_irq = of_property_read_bool(np,
"ti,system-uses-second-madc-irq");
madc->imr = madc->use_second_irq ? TWL4030_MADC_IMR2 :
TWL4030_MADC_IMR1;
madc->isr = madc->use_second_irq ? TWL4030_MADC_ISR2 :
TWL4030_MADC_ISR1;
ret = twl4030_madc_set_power(madc, 1);
if (ret < 0)
return ret;
ret = twl4030_madc_set_current_generator(madc, 0, 1);
if (ret < 0)
goto err_current_generator;
ret = twl_i2c_read_u8(TWL_MODULE_MAIN_CHARGE,
&regval, TWL4030_BCI_BCICTL1);
if (ret) {
dev_err(&pdev->dev, "unable to read reg BCI CTL1 0x%X\n",
TWL4030_BCI_BCICTL1);
goto err_i2c;
}
regval |= TWL4030_BCI_MESBAT;
ret = twl_i2c_write_u8(TWL_MODULE_MAIN_CHARGE,
regval, TWL4030_BCI_BCICTL1);
if (ret) {
dev_err(&pdev->dev, "unable to write reg BCI Ctl1 0x%X\n",
TWL4030_BCI_BCICTL1);
goto err_i2c;
}
/* Check that MADC clock is on */
ret = twl_i2c_read_u8(TWL4030_MODULE_INTBR, &regval, TWL4030_REG_GPBR1);
if (ret) {
dev_err(&pdev->dev, "unable to read reg GPBR1 0x%X\n",
TWL4030_REG_GPBR1);
goto err_i2c;
}
/* If MADC clk is not on, turn it on */
if (!(regval & TWL4030_GPBR1_MADC_HFCLK_EN)) {
dev_info(&pdev->dev, "clk disabled, enabling\n");
regval |= TWL4030_GPBR1_MADC_HFCLK_EN;
ret = twl_i2c_write_u8(TWL4030_MODULE_INTBR, regval,
TWL4030_REG_GPBR1);
if (ret) {
dev_err(&pdev->dev, "unable to write reg GPBR1 0x%X\n",
TWL4030_REG_GPBR1);
goto err_i2c;
}
}
platform_set_drvdata(pdev, iio_dev);
mutex_init(&madc->lock);
irq = platform_get_irq(pdev, 0);
ret = devm_request_threaded_irq(&pdev->dev, irq, NULL,
twl4030_madc_threaded_irq_handler,
IRQF_TRIGGER_RISING | IRQF_ONESHOT,
"twl4030_madc", madc);
if (ret) {
dev_err(&pdev->dev, "could not request irq\n");
goto err_i2c;
}
twl4030_madc = madc;
/* Configure MADC[3:6] */
ret = twl_i2c_read_u8(TWL_MODULE_USB, &regval,
TWL4030_USB_CARKIT_ANA_CTRL);
if (ret) {
dev_err(&pdev->dev, "unable to read reg CARKIT_ANA_CTRL 0x%X\n",
TWL4030_USB_CARKIT_ANA_CTRL);
goto err_i2c;
}
regval |= TWL4030_USB_SEL_MADC_MCPC;
ret = twl_i2c_write_u8(TWL_MODULE_USB, regval,
TWL4030_USB_CARKIT_ANA_CTRL);
if (ret) {
dev_err(&pdev->dev, "unable to write reg CARKIT_ANA_CTRL 0x%X\n",
TWL4030_USB_CARKIT_ANA_CTRL);
goto err_i2c;
}
/* Enable 3v1 bias regulator for MADC[3:6] */
madc->usb3v1 = devm_regulator_get(madc->dev, "vusb3v1");
if (IS_ERR(madc->usb3v1)) {
ret = -ENODEV;
goto err_i2c;
}
ret = regulator_enable(madc->usb3v1);
if (ret) {
dev_err(madc->dev, "could not enable 3v1 bias regulator\n");
goto err_i2c;
}
ret = iio_device_register(iio_dev);
if (ret) {
dev_err(&pdev->dev, "could not register iio device\n");
goto err_usb3v1;
}
return 0;
err_usb3v1:
regulator_disable(madc->usb3v1);
err_i2c:
twl4030_madc_set_current_generator(madc, 0, 0);
err_current_generator:
twl4030_madc_set_power(madc, 0);
return ret;
}
static int twl4030_madc_remove(struct platform_device *pdev)
{
struct iio_dev *iio_dev = platform_get_drvdata(pdev);
struct twl4030_madc_data *madc = iio_priv(iio_dev);
iio_device_unregister(iio_dev);
twl4030_madc_set_current_generator(madc, 0, 0);
twl4030_madc_set_power(madc, 0);
regulator_disable(madc->usb3v1);
return 0;
}
#ifdef CONFIG_OF
static const struct of_device_id twl_madc_of_match[] = {
{ .compatible = "ti,twl4030-madc", },
{ },
};
MODULE_DEVICE_TABLE(of, twl_madc_of_match);
#endif
static struct platform_driver twl4030_madc_driver = {
.probe = twl4030_madc_probe,
.remove = twl4030_madc_remove,
.driver = {
.name = "twl4030_madc",
.of_match_table = of_match_ptr(twl_madc_of_match),
},
};
module_platform_driver(twl4030_madc_driver);
MODULE_DESCRIPTION("TWL4030 ADC driver");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("J Keerthy");
MODULE_ALIAS("platform:twl4030_madc");
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