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authorTodd Fischer <todd.fischer@ridgerun.com>2010-04-05 17:53:12 -0600
committerSamuel Ortiz <sameo@linux.intel.com>2010-05-28 01:37:38 +0200
commit752599667048898b6969e06e4637f906b04ec752 (patch)
tree91fd727ff21048eac193a84ff26833ff69647d5d /drivers/input/touchscreen/tps6507x-ts.c
parent31dd6a2672e337f5de188df3e5169ee732798236 (diff)
input: Touchscreen driver for TPS6507x
Add touch screen input driver for TPS6507x family of multi-function chips. Uses the TPS6507x MFD driver. No interrupt support due to testing limitations of current hardware. Signed-off-by: Todd Fischer <todd.fischer@ridgerun.com> Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Diffstat (limited to 'drivers/input/touchscreen/tps6507x-ts.c')
-rw-r--r--drivers/input/touchscreen/tps6507x-ts.c400
1 files changed, 400 insertions, 0 deletions
diff --git a/drivers/input/touchscreen/tps6507x-ts.c b/drivers/input/touchscreen/tps6507x-ts.c
new file mode 100644
index 000000000000..5de80a1a730b
--- /dev/null
+++ b/drivers/input/touchscreen/tps6507x-ts.c
@@ -0,0 +1,400 @@
+/*
+ * drivers/input/touchscreen/tps6507x_ts.c
+ *
+ * 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/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 input_dev *input_dev;
+ struct device *dev;
+ char phys[32];
+ struct workqueue_struct *wq;
+ struct delayed_work work;
+ unsigned polling; /* polling is active */
+ struct ts_event tc;
+ struct tps6507x_dev *mfd;
+ u16 model;
+ unsigned pendown;
+ int irq;
+ void (*clear_penirq)(void);
+ unsigned long poll_period; /* ms */
+ u16 min_pressure;
+ int vref; /* non-zero to leave vref on */
+};
+
+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_handler(struct work_struct *work)
+{
+ struct tps6507x_ts *tsc = container_of(work,
+ struct tps6507x_ts, work.work);
+ struct input_dev *input_dev = tsc->input_dev;
+ int pendown;
+ int schd;
+ int poll = 0;
+ 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 = 0;
+ }
+
+ 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 = 1;
+ poll = 1;
+ }
+
+done:
+ /* always poll if not using interrupts */
+ poll = 1;
+
+ if (poll) {
+ schd = queue_delayed_work(tsc->wq, &tsc->work,
+ tsc->poll_period * HZ / 1000);
+ if (schd)
+ tsc->polling = 1;
+ else {
+ tsc->polling = 0;
+ dev_err(tsc->dev, "re-schedule failed");
+ }
+ } else
+ tsc->polling = 0;
+
+ ret = tps6507x_adc_standby(tsc);
+}
+
+static int tps6507x_ts_probe(struct platform_device *pdev)
+{
+ int error;
+ struct tps6507x_ts *tsc;
+ struct tps6507x_dev *tps6507x_dev = dev_get_drvdata(pdev->dev.parent);
+ struct touchscreen_init_data *init_data;
+ struct input_dev *input_dev;
+ struct tps6507x_board *tps_board;
+ int schd;
+
+ /**
+ * tps_board points to pmic related constants
+ * coming from the board-evm file.
+ */
+
+ tps_board = (struct tps6507x_board *)tps6507x_dev->dev->platform_data;
+
+ if (!tps_board) {
+ dev_err(tps6507x_dev->dev,
+ "Could not find tps6507x platform data\n");
+ return -EIO;
+ }
+
+ /**
+ * 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");
+ error = -ENOMEM;
+ goto err0;
+ }
+
+ tps6507x_dev->ts = tsc;
+ tsc->mfd = tps6507x_dev;
+ tsc->dev = tps6507x_dev->dev;
+ input_dev = input_allocate_device();
+ if (!input_dev) {
+ dev_err(tsc->dev, "Failed to allocate input device.\n");
+ error = -ENOMEM;
+ goto err1;
+ }
+
+ 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->id.bustype = BUS_I2C;
+ input_dev->dev.parent = tsc->dev;
+
+ snprintf(tsc->phys, sizeof(tsc->phys),
+ "%s/input0", dev_name(tsc->dev));
+ input_dev->phys = tsc->phys;
+
+ dev_dbg(tsc->dev, "device: %s\n", input_dev->phys);
+
+ input_set_drvdata(input_dev, tsc);
+
+ tsc->input_dev = input_dev;
+
+ INIT_DELAYED_WORK(&tsc->work, tps6507x_ts_handler);
+ tsc->wq = create_workqueue("TPS6507x Touchscreen");
+
+ if (init_data) {
+ tsc->poll_period = init_data->poll_period;
+ tsc->vref = init_data->vref;
+ tsc->min_pressure = init_data->min_pressure;
+ input_dev->id.vendor = init_data->vendor;
+ input_dev->id.product = init_data->product;
+ input_dev->id.version = init_data->version;
+ } else {
+ tsc->poll_period = TSC_DEFAULT_POLL_PERIOD;
+ tsc->min_pressure = TPS_DEFAULT_MIN_PRESSURE;
+ }
+
+ error = tps6507x_adc_standby(tsc);
+ if (error)
+ goto err2;
+
+ error = input_register_device(input_dev);
+ if (error)
+ goto err2;
+
+ schd = queue_delayed_work(tsc->wq, &tsc->work,
+ tsc->poll_period * HZ / 1000);
+
+ if (schd)
+ tsc->polling = 1;
+ else {
+ tsc->polling = 0;
+ dev_err(tsc->dev, "schedule failed");
+ goto err2;
+ }
+
+ return 0;
+
+err2:
+ cancel_delayed_work(&tsc->work);
+ flush_workqueue(tsc->wq);
+ destroy_workqueue(tsc->wq);
+ tsc->wq = 0;
+ input_free_device(input_dev);
+err1:
+ kfree(tsc);
+ tps6507x_dev->ts = NULL;
+err0:
+ return error;
+}
+
+static int __devexit tps6507x_ts_remove(struct platform_device *pdev)
+{
+ struct tps6507x_dev *tps6507x_dev = platform_get_drvdata(pdev);
+ struct tps6507x_ts *tsc = tps6507x_dev->ts;
+ struct input_dev *input_dev = tsc->input_dev;
+
+ if (!tsc)
+ return 0;
+
+ cancel_delayed_work(&tsc->work);
+ flush_workqueue(tsc->wq);
+ destroy_workqueue(tsc->wq);
+ tsc->wq = 0;
+
+ input_free_device(input_dev);
+
+ tps6507x_dev->ts = NULL;
+ kfree(tsc);
+
+ return 0;
+}
+
+static struct platform_driver tps6507x_ts_driver = {
+ .driver = {
+ .name = "tps6507x-ts",
+ .owner = THIS_MODULE,
+ },
+ .probe = tps6507x_ts_probe,
+ .remove = __devexit_p(tps6507x_ts_remove),
+};
+
+static int __init tps6507x_ts_init(void)
+{
+ return platform_driver_register(&tps6507x_ts_driver);
+}
+module_init(tps6507x_ts_init);
+
+static void __exit tps6507x_ts_exit(void)
+{
+ platform_driver_unregister(&tps6507x_ts_driver);
+}
+module_exit(tps6507x_ts_exit);
+
+MODULE_AUTHOR("Todd Fischer <todd.fischer@ridgerun.com>");
+MODULE_DESCRIPTION("TPS6507x - TouchScreen driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:tps6507x-tsc");