| /* |
| * 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 = kzalloc(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 = input_allocate_polled_device(); |
| if (!poll_dev) { |
| dev_err(tsc->dev, "Failed to allocate polled input device.\n"); |
| error = -ENOMEM; |
| goto err_free_mem; |
| } |
| |
| 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) |
| goto err_free_polled_dev; |
| |
| error = input_register_polled_device(poll_dev); |
| if (error) |
| goto err_free_polled_dev; |
| |
| platform_set_drvdata(pdev, tsc); |
| |
| return 0; |
| |
| err_free_polled_dev: |
| input_free_polled_device(poll_dev); |
| err_free_mem: |
| kfree(tsc); |
| return error; |
| } |
| |
| static int tps6507x_ts_remove(struct platform_device *pdev) |
| { |
| struct tps6507x_ts *tsc = platform_get_drvdata(pdev); |
| struct input_polled_dev *poll_dev = tsc->poll_dev; |
| |
| input_unregister_polled_device(poll_dev); |
| input_free_polled_device(poll_dev); |
| |
| kfree(tsc); |
| |
| return 0; |
| } |
| |
| static struct platform_driver tps6507x_ts_driver = { |
| .driver = { |
| .name = "tps6507x-ts", |
| }, |
| .probe = tps6507x_ts_probe, |
| .remove = tps6507x_ts_remove, |
| }; |
| 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"); |