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Diffstat (limited to 'kernel/drivers/input/touchscreen/tps6507x-ts.c')
-rw-r--r--kernel/drivers/input/touchscreen/tps6507x-ts.c326
1 files changed, 326 insertions, 0 deletions
diff --git a/kernel/drivers/input/touchscreen/tps6507x-ts.c b/kernel/drivers/input/touchscreen/tps6507x-ts.c
new file mode 100644
index 000000000..4ffd829d1
--- /dev/null
+++ b/kernel/drivers/input/touchscreen/tps6507x-ts.c
@@ -0,0 +1,326 @@
+/*
+ * 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)
+{
+ int err;
+
+ err = tsc->mfd->read_dev(tsc->mfd, reg, 1, data);
+
+ if (err)
+ return err;
+
+ return 0;
+}
+
+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");