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Diffstat (limited to '')
| -rw-r--r-- | drivers/iio/adc/twl4030-madc.c | 954 |
1 files changed, 954 insertions, 0 deletions
diff --git a/drivers/iio/adc/twl4030-madc.c b/drivers/iio/adc/twl4030-madc.c new file mode 100644 index 000000000..8c019bb66 --- /dev/null +++ b/drivers/iio/adc/twl4030-madc.c @@ -0,0 +1,954 @@ +/* + * + * 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, ®, 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, + ®val, 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, + ®val, 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, + ®val, 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, ®val, 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, ®val, + 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"); |