|  | /* | 
|  | * Touchscreen driver for the tps6507x chip. | 
|  | * | 
|  | * Copyright (c) 2009 RidgeRun (todd.fischer@ridgerun.com) | 
|  | * | 
|  | * Credits: | 
|  | * | 
|  | *    Using code from tsc2007, MtekVision Co., Ltd. | 
|  | * | 
|  | * For licencing details see kernel-base/COPYING | 
|  | * | 
|  | * TPS65070, TPS65073, TPS650731, and TPS650732 support | 
|  | * 10 bit touch screen interface. | 
|  | */ | 
|  |  | 
|  | #include <linux/module.h> | 
|  | #include <linux/workqueue.h> | 
|  | #include <linux/slab.h> | 
|  | #include <linux/input.h> | 
|  | #include <linux/input-polldev.h> | 
|  | #include <linux/platform_device.h> | 
|  | #include <linux/mfd/tps6507x.h> | 
|  | #include <linux/input/tps6507x-ts.h> | 
|  | #include <linux/delay.h> | 
|  |  | 
|  | #define TSC_DEFAULT_POLL_PERIOD 30 /* ms */ | 
|  | #define TPS_DEFAULT_MIN_PRESSURE 0x30 | 
|  | #define MAX_10BIT ((1 << 10) - 1) | 
|  |  | 
|  | #define	TPS6507X_ADCONFIG_CONVERT_TS (TPS6507X_ADCONFIG_AD_ENABLE | \ | 
|  | TPS6507X_ADCONFIG_START_CONVERSION | \ | 
|  | TPS6507X_ADCONFIG_INPUT_REAL_TSC) | 
|  | #define	TPS6507X_ADCONFIG_POWER_DOWN_TS (TPS6507X_ADCONFIG_INPUT_REAL_TSC) | 
|  |  | 
|  | struct ts_event { | 
|  | u16	x; | 
|  | u16	y; | 
|  | u16	pressure; | 
|  | }; | 
|  |  | 
|  | struct tps6507x_ts { | 
|  | struct device		*dev; | 
|  | struct input_polled_dev	*poll_dev; | 
|  | struct tps6507x_dev	*mfd; | 
|  | char			phys[32]; | 
|  | struct ts_event		tc; | 
|  | u16			min_pressure; | 
|  | bool			pendown; | 
|  | }; | 
|  |  | 
|  | static int tps6507x_read_u8(struct tps6507x_ts *tsc, u8 reg, u8 *data) | 
|  | { | 
|  | return tsc->mfd->read_dev(tsc->mfd, reg, 1, data); | 
|  | } | 
|  |  | 
|  | static int tps6507x_write_u8(struct tps6507x_ts *tsc, u8 reg, u8 data) | 
|  | { | 
|  | return tsc->mfd->write_dev(tsc->mfd, reg, 1, &data); | 
|  | } | 
|  |  | 
|  | static s32 tps6507x_adc_conversion(struct tps6507x_ts *tsc, | 
|  | u8 tsc_mode, u16 *value) | 
|  | { | 
|  | s32 ret; | 
|  | u8 adc_status; | 
|  | u8 result; | 
|  |  | 
|  | /* Route input signal to A/D converter */ | 
|  |  | 
|  | ret = tps6507x_write_u8(tsc, TPS6507X_REG_TSCMODE, tsc_mode); | 
|  | if (ret) { | 
|  | dev_err(tsc->dev, "TSC mode read failed\n"); | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | /* Start A/D conversion */ | 
|  |  | 
|  | ret = tps6507x_write_u8(tsc, TPS6507X_REG_ADCONFIG, | 
|  | TPS6507X_ADCONFIG_CONVERT_TS); | 
|  | if (ret) { | 
|  | dev_err(tsc->dev, "ADC config write failed\n"); | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | do { | 
|  | ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADCONFIG, | 
|  | &adc_status); | 
|  | if (ret) { | 
|  | dev_err(tsc->dev, "ADC config read failed\n"); | 
|  | goto err; | 
|  | } | 
|  | } while (adc_status & TPS6507X_ADCONFIG_START_CONVERSION); | 
|  |  | 
|  | ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADRESULT_2, &result); | 
|  | if (ret) { | 
|  | dev_err(tsc->dev, "ADC result 2 read failed\n"); | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | *value = (result & TPS6507X_REG_ADRESULT_2_MASK) << 8; | 
|  |  | 
|  | ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADRESULT_1, &result); | 
|  | if (ret) { | 
|  | dev_err(tsc->dev, "ADC result 1 read failed\n"); | 
|  | goto err; | 
|  | } | 
|  |  | 
|  | *value |= result; | 
|  |  | 
|  | dev_dbg(tsc->dev, "TSC channel %d = 0x%X\n", tsc_mode, *value); | 
|  |  | 
|  | err: | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | /* Need to call tps6507x_adc_standby() after using A/D converter for the | 
|  | * touch screen interrupt to work properly. | 
|  | */ | 
|  |  | 
|  | static s32 tps6507x_adc_standby(struct tps6507x_ts *tsc) | 
|  | { | 
|  | s32 ret; | 
|  | s32 loops = 0; | 
|  | u8 val; | 
|  |  | 
|  | ret = tps6507x_write_u8(tsc,  TPS6507X_REG_ADCONFIG, | 
|  | TPS6507X_ADCONFIG_INPUT_TSC); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | ret = tps6507x_write_u8(tsc, TPS6507X_REG_TSCMODE, | 
|  | TPS6507X_TSCMODE_STANDBY); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | ret = tps6507x_read_u8(tsc, TPS6507X_REG_INT, &val); | 
|  | if (ret) | 
|  | return ret; | 
|  |  | 
|  | while (val & TPS6507X_REG_TSC_INT) { | 
|  | mdelay(10); | 
|  | ret = tps6507x_read_u8(tsc, TPS6507X_REG_INT, &val); | 
|  | if (ret) | 
|  | return ret; | 
|  | loops++; | 
|  | } | 
|  |  | 
|  | return ret; | 
|  | } | 
|  |  | 
|  | static void tps6507x_ts_poll(struct input_polled_dev *poll_dev) | 
|  | { | 
|  | struct tps6507x_ts *tsc = poll_dev->private; | 
|  | struct input_dev *input_dev = poll_dev->input; | 
|  | bool pendown; | 
|  | s32 ret; | 
|  |  | 
|  | ret = tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_PRESSURE, | 
|  | &tsc->tc.pressure); | 
|  | if (ret) | 
|  | goto done; | 
|  |  | 
|  | pendown = tsc->tc.pressure > tsc->min_pressure; | 
|  |  | 
|  | if (unlikely(!pendown && tsc->pendown)) { | 
|  | dev_dbg(tsc->dev, "UP\n"); | 
|  | input_report_key(input_dev, BTN_TOUCH, 0); | 
|  | input_report_abs(input_dev, ABS_PRESSURE, 0); | 
|  | input_sync(input_dev); | 
|  | tsc->pendown = false; | 
|  | } | 
|  |  | 
|  | if (pendown) { | 
|  |  | 
|  | if (!tsc->pendown) { | 
|  | dev_dbg(tsc->dev, "DOWN\n"); | 
|  | input_report_key(input_dev, BTN_TOUCH, 1); | 
|  | } else | 
|  | dev_dbg(tsc->dev, "still down\n"); | 
|  |  | 
|  | ret =  tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_X_POSITION, | 
|  | &tsc->tc.x); | 
|  | if (ret) | 
|  | goto done; | 
|  |  | 
|  | ret =  tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_Y_POSITION, | 
|  | &tsc->tc.y); | 
|  | if (ret) | 
|  | goto done; | 
|  |  | 
|  | input_report_abs(input_dev, ABS_X, tsc->tc.x); | 
|  | input_report_abs(input_dev, ABS_Y, tsc->tc.y); | 
|  | input_report_abs(input_dev, ABS_PRESSURE, tsc->tc.pressure); | 
|  | input_sync(input_dev); | 
|  | tsc->pendown = true; | 
|  | } | 
|  |  | 
|  | done: | 
|  | tps6507x_adc_standby(tsc); | 
|  | } | 
|  |  | 
|  | static int tps6507x_ts_probe(struct platform_device *pdev) | 
|  | { | 
|  | struct tps6507x_dev *tps6507x_dev = dev_get_drvdata(pdev->dev.parent); | 
|  | const struct tps6507x_board *tps_board; | 
|  | const struct touchscreen_init_data *init_data; | 
|  | struct tps6507x_ts *tsc; | 
|  | struct input_polled_dev *poll_dev; | 
|  | struct input_dev *input_dev; | 
|  | int error; | 
|  |  | 
|  | /* | 
|  | * tps_board points to pmic related constants | 
|  | * coming from the board-evm file. | 
|  | */ | 
|  | tps_board = dev_get_platdata(tps6507x_dev->dev); | 
|  | if (!tps_board) { | 
|  | dev_err(tps6507x_dev->dev, | 
|  | "Could not find tps6507x platform data\n"); | 
|  | return -ENODEV; | 
|  | } | 
|  |  | 
|  | /* | 
|  | * init_data points to array of regulator_init structures | 
|  | * coming from the board-evm file. | 
|  | */ | 
|  | init_data = tps_board->tps6507x_ts_init_data; | 
|  |  | 
|  | tsc = devm_kzalloc(&pdev->dev, sizeof(struct tps6507x_ts), GFP_KERNEL); | 
|  | if (!tsc) { | 
|  | dev_err(tps6507x_dev->dev, "failed to allocate driver data\n"); | 
|  | return -ENOMEM; | 
|  | } | 
|  |  | 
|  | tsc->mfd = tps6507x_dev; | 
|  | tsc->dev = tps6507x_dev->dev; | 
|  | tsc->min_pressure = init_data ? | 
|  | init_data->min_pressure : TPS_DEFAULT_MIN_PRESSURE; | 
|  |  | 
|  | snprintf(tsc->phys, sizeof(tsc->phys), | 
|  | "%s/input0", dev_name(tsc->dev)); | 
|  |  | 
|  | poll_dev = devm_input_allocate_polled_device(&pdev->dev); | 
|  | if (!poll_dev) { | 
|  | dev_err(tsc->dev, "Failed to allocate polled input device.\n"); | 
|  | return -ENOMEM; | 
|  | } | 
|  |  | 
|  | tsc->poll_dev = poll_dev; | 
|  |  | 
|  | poll_dev->private = tsc; | 
|  | poll_dev->poll = tps6507x_ts_poll; | 
|  | poll_dev->poll_interval = init_data ? | 
|  | init_data->poll_period : TSC_DEFAULT_POLL_PERIOD; | 
|  |  | 
|  | input_dev = poll_dev->input; | 
|  | input_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_ABS); | 
|  | input_dev->keybit[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH); | 
|  |  | 
|  | input_set_abs_params(input_dev, ABS_X, 0, MAX_10BIT, 0, 0); | 
|  | input_set_abs_params(input_dev, ABS_Y, 0, MAX_10BIT, 0, 0); | 
|  | input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_10BIT, 0, 0); | 
|  |  | 
|  | input_dev->name = "TPS6507x Touchscreen"; | 
|  | input_dev->phys = tsc->phys; | 
|  | input_dev->dev.parent = tsc->dev; | 
|  | input_dev->id.bustype = BUS_I2C; | 
|  | if (init_data) { | 
|  | input_dev->id.vendor = init_data->vendor; | 
|  | input_dev->id.product = init_data->product; | 
|  | input_dev->id.version = init_data->version; | 
|  | } | 
|  |  | 
|  | error = tps6507x_adc_standby(tsc); | 
|  | if (error) | 
|  | return error; | 
|  |  | 
|  | error = input_register_polled_device(poll_dev); | 
|  | if (error) | 
|  | return error; | 
|  |  | 
|  | return 0; | 
|  | } | 
|  |  | 
|  | static struct platform_driver tps6507x_ts_driver = { | 
|  | .driver = { | 
|  | .name = "tps6507x-ts", | 
|  | }, | 
|  | .probe = tps6507x_ts_probe, | 
|  | }; | 
|  | module_platform_driver(tps6507x_ts_driver); | 
|  |  | 
|  | MODULE_AUTHOR("Todd Fischer <todd.fischer@ridgerun.com>"); | 
|  | MODULE_DESCRIPTION("TPS6507x - TouchScreen driver"); | 
|  | MODULE_LICENSE("GPL v2"); | 
|  | MODULE_ALIAS("platform:tps6507x-ts"); |