// SPDX-License-Identifier: GPL-2.0-only /* * TWL6030 GPADC module driver * * Copyright (C) 2009-2013 Texas Instruments Inc. * Nishant Kamat <[email protected]> * Balaji T K <[email protected]> * Graeme Gregory <[email protected]> * Girish S Ghongdemath <[email protected]> * Ambresh K <[email protected]> * Oleksandr Kozaruk <[email protected] * * Based on twl4030-madc.c * Copyright (C) 2008 Nokia Corporation * Mikko Ylinen <[email protected]> */ #include <linux/interrupt.h> #include <linux/kernel.h> #include <linux/mod_devicetable.h> #include <linux/module.h> #include <linux/platform_device.h> #include <linux/property.h> #include <linux/mfd/twl.h> #include <linux/iio/iio.h> #include <linux/iio/sysfs.h> #define DRIVER_NAME … /* * twl6030 per TRM has 17 channels, and twl6032 has 19 channels * 2 test network channels are not used, * 2 die temperature channels are not used either, as it is not * defined how to convert ADC value to temperature */ #define TWL6030_GPADC_USED_CHANNELS … #define TWL6030_GPADC_MAX_CHANNELS … #define TWL6032_GPADC_USED_CHANNELS … #define TWL6032_GPADC_MAX_CHANNELS … #define TWL6030_GPADC_NUM_TRIM_REGS … #define TWL6030_GPADC_CTRL_P1 … #define TWL6032_GPADC_GPSELECT_ISB … #define TWL6032_GPADC_CTRL_P1 … #define TWL6032_GPADC_GPCH0_LSB … #define TWL6032_GPADC_GPCH0_MSB … #define TWL6030_GPADC_CTRL_P1_SP1 … #define TWL6030_GPADC_GPCH0_LSB … #define TWL6030_GPADC_RT_SW1_EOC_MASK … #define TWL6030_GPADC_TRIM1 … #define TWL6030_REG_TOGGLE1 … #define TWL6030_GPADCS … #define TWL6030_GPADCR … #define USB_VBUS_CTRL_SET … #define USB_ID_CTRL_SET … #define TWL6030_MISC1 … #define VBUS_MEAS … #define ID_MEAS … #define VAC_MEAS … #define VBAT_MEAS … #define BB_MEAS … /** * struct twl6030_chnl_calib - channel calibration * @gain: slope coefficient for ideal curve * @gain_error: gain error * @offset_error: offset of the real curve */ struct twl6030_chnl_calib { … }; /** * struct twl6030_ideal_code - GPADC calibration parameters * GPADC is calibrated in two points: close to the beginning and * to the and of the measurable input range * * @channel: channel number * @code1: ideal code for the input at the beginning * @code2: ideal code for at the end of the range * @volt1: voltage input at the beginning(low voltage) * @volt2: voltage input at the end(high voltage) */ struct twl6030_ideal_code { … }; struct twl6030_gpadc_data; /** * struct twl6030_gpadc_platform_data - platform specific data * @nchannels: number of GPADC channels * @iio_channels: iio channels * @ideal: pointer to calibration parameters * @start_conversion: pointer to ADC start conversion function * @channel_to_reg: pointer to ADC function to convert channel to * register address for reading conversion result * @calibrate: pointer to calibration function */ struct twl6030_gpadc_platform_data { … }; /** * struct twl6030_gpadc_data - GPADC data * @dev: device pointer * @lock: mutual exclusion lock for the structure * @irq_complete: completion to signal end of conversion * @twl6030_cal_tbl: pointer to calibration data for each * channel with gain error and offset * @pdata: pointer to device specific data */ struct twl6030_gpadc_data { … }; /* * channels 11, 12, 13, 15 and 16 have no calibration data * calibration offset is same for channels 1, 3, 4, 5 * * The data is taken from GPADC_TRIM registers description. * GPADC_TRIM registers keep difference between the code measured * at volt1 and volt2 input voltages and corresponding code1 and code2 */ static const struct twl6030_ideal_code twl6030_ideal[TWL6030_GPADC_USED_CHANNELS] = …; static const struct twl6030_ideal_code twl6032_ideal[TWL6032_GPADC_USED_CHANNELS] = …; static inline int twl6030_gpadc_write(u8 reg, u8 val) { … } static inline int twl6030_gpadc_read(u8 reg, u8 *val) { … } static int twl6030_gpadc_enable_irq(u8 mask) { … } static void twl6030_gpadc_disable_irq(u8 mask) { … } static irqreturn_t twl6030_gpadc_irq_handler(int irq, void *indio_dev) { … } static int twl6030_start_conversion(int channel) { … } static int twl6032_start_conversion(int channel) { … } static u8 twl6030_channel_to_reg(int channel) { … } static u8 twl6032_channel_to_reg(int channel) { … } static int twl6030_gpadc_lookup(const struct twl6030_ideal_code *ideal, int channel, int size) { … } static int twl6030_channel_calibrated(const struct twl6030_gpadc_platform_data *pdata, int channel) { … } static int twl6030_gpadc_make_correction(struct twl6030_gpadc_data *gpadc, int channel, int raw_code) { … } static int twl6030_gpadc_get_raw(struct twl6030_gpadc_data *gpadc, int channel, int *res) { … } static int twl6030_gpadc_get_processed(struct twl6030_gpadc_data *gpadc, int channel, int *val) { … } static int twl6030_gpadc_read_raw(struct iio_dev *indio_dev, const struct iio_chan_spec *chan, int *val, int *val2, long mask) { … } /* * The GPADC channels are calibrated using a two point calibration method. * The channels measured with two known values: volt1 and volt2, and * ideal corresponding output codes are known: code1, code2. * The difference(d1, d2) between ideal and measured codes stored in trim * registers. * The goal is to find offset and gain of the real curve for each calibrated * channel. * gain: k = 1 + ((d2 - d1) / (x2 - x1)) * offset: b = d1 + (k - 1) * x1 */ static void twl6030_calibrate_channel(struct twl6030_gpadc_data *gpadc, int channel, int d1, int d2) { … } static inline int twl6030_gpadc_get_trim_offset(s8 d) { … } static int twl6030_calibration(struct twl6030_gpadc_data *gpadc) { … } static int twl6032_get_trim_value(u8 *trim_regs, unsigned int reg0, unsigned int reg1, unsigned int mask0, unsigned int mask1, unsigned int shift0) { … } static int twl6032_calibration(struct twl6030_gpadc_data *gpadc) { … } #define TWL6030_GPADC_CHAN(chn, _type, chan_info) … static const struct iio_chan_spec twl6030_gpadc_iio_channels[] = …; static const struct iio_chan_spec twl6032_gpadc_iio_channels[] = …; static const struct iio_info twl6030_gpadc_iio_info = …; static const struct twl6030_gpadc_platform_data twl6030_pdata = …; static const struct twl6030_gpadc_platform_data twl6032_pdata = …; static const struct of_device_id of_twl6030_match_tbl[] = …; MODULE_DEVICE_TABLE(of, of_twl6030_match_tbl); static int twl6030_gpadc_probe(struct platform_device *pdev) { … } static void twl6030_gpadc_remove(struct platform_device *pdev) { … } static int twl6030_gpadc_suspend(struct device *pdev) { int ret; ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCR, TWL6030_REG_TOGGLE1); if (ret) dev_err(pdev, "error resetting GPADC (%d)!\n", ret); return 0; }; static int twl6030_gpadc_resume(struct device *pdev) { int ret; ret = twl_i2c_write_u8(TWL6030_MODULE_ID1, TWL6030_GPADCS, TWL6030_REG_TOGGLE1); if (ret) dev_err(pdev, "error setting GPADC (%d)!\n", ret); return 0; }; static DEFINE_SIMPLE_DEV_PM_OPS(twl6030_gpadc_pm_ops, twl6030_gpadc_suspend, twl6030_gpadc_resume); static struct platform_driver twl6030_gpadc_driver = …; module_platform_driver(…) …; MODULE_ALIAS(…) …; MODULE_AUTHOR(…) …; MODULE_AUTHOR(…) …; MODULE_AUTHOR(…) …; MODULE_DESCRIPTION(…) …; MODULE_LICENSE(…) …;
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