The TPS6507x family of Texas Instruments power management ICs (pmic)
are multi-function chips that include voltage regulation and touch
screen controller capabilities. This patch adds a touch screen
input driver for the TPS6507x pmic. There was an existing regulator
driver. Before the touch screen driver could be added, a multi-function
device (MFD) driver was needed and the regulator driver modified to
use the MDF driver. Patches for these changes have been posted and
reviewed. The TPS6507x touch screen driver applies cleanly to the
MFD GIT repo after the above referenced patches are applied. If I
should use a different approach for the touch screen driver, please
let me know.
Signed-off-by: Todd Fischer <todd.fischer@xxxxxxxxxxxx>
---
arch/arm/mach-davinci/board-da850-evm.c | 12 +
drivers/input/touchscreen/Kconfig | 13 +
drivers/input/touchscreen/Makefile | 1 +
drivers/input/touchscreen/tps6507x-ts.c | 400 +++++++++++++++++++++++++++++++
drivers/mfd/tps6507x.c | 3 +
include/linux/input/tps6507x-ts.h | 24 ++
include/linux/mfd/tps6507x.h | 2 +
7 files changed, 455 insertions(+), 0 deletions(-)
create mode 100644 drivers/input/touchscreen/tps6507x-ts.c
create mode 100644 include/linux/input/tps6507x-ts.h
diff --git a/arch/arm/mach-davinci/board-da850-evm.c b/arch/arm/mach-davinci/board-da850-evm.c
index d059924..b3cbb32 100644
--- a/arch/arm/mach-davinci/board-da850-evm.c
+++ b/arch/arm/mach-davinci/board-da850-evm.c
@@ -25,6 +25,8 @@
#include <linux/mtd/partitions.h>
#include <linux/mtd/physmap.h>
#include <linux/regulator/machine.h>
+#include <linux/mfd/tps6507x.h>
+#include <linux/input/tps6507x-ts.h>
#include <asm/mach-types.h>
#include <asm/mach/arch.h>
@@ -534,8 +536,18 @@ struct regulator_init_data tps65070_regulator_data[] = {
},
};
+static struct touchscreen_init_data tps6507x_touchscreen_data = {
+ .poll_period = 30, /* ms between touch samples */
+ .min_pressure = 0x30, /* minimum pressure to trigger touch */
+ .vref = 0, /* turn off vref when not using A/D */
+ .vendor = 0, /* /sys/class/input/input?/id/vendor */
+ .product = 65070, /* /sys/class/input/input?/id/product */
+ .version = 0x100, /* /sys/class/input/input?/id/version */
+};
+
static struct tps6507x_board tps_board = {
.tps6507x_pmic_init_data = &tps65070_regulator_data[0],
+ .tps6507x_ts_init_data = &tps6507x_touchscreen_data,
};
static struct i2c_board_info __initdata da850evm_tps65070_info[] = {
diff --git a/drivers/input/touchscreen/Kconfig b/drivers/input/touchscreen/Kconfig
index 8a8fa4d..6166aa8 100644
--- a/drivers/input/touchscreen/Kconfig
+++ b/drivers/input/touchscreen/Kconfig
@@ -594,4 +594,17 @@ config TOUCHSCREEN_PCAP
To compile this driver as a module, choose M here: the
module will be called pcap_ts.
+
+config TOUCHSCREEN_TPS6507X
+ tristate "TPS6507x based touchscreens"
+ depends on I2C
+ help
+ Say Y here if you have a TPS6507x based touchscreen
+ controller.
+
+ If unsure, say N.
+
+ To compile this driver as a module, choose M here: the
+ module will be called tps6507x_ts.
+
endif
diff --git a/drivers/input/touchscreen/Makefile b/drivers/input/touchscreen/Makefile
index 7fef7d5..cfa83d0 100644
--- a/drivers/input/touchscreen/Makefile
+++ b/drivers/input/touchscreen/Makefile
@@ -46,3 +46,4 @@ obj-$(CONFIG_TOUCHSCREEN_WM97XX_ATMEL) += atmel-wm97xx.o
obj-$(CONFIG_TOUCHSCREEN_WM97XX_MAINSTONE) += mainstone-wm97xx.o
obj-$(CONFIG_TOUCHSCREEN_WM97XX_ZYLONITE) += zylonite-wm97xx.o
obj-$(CONFIG_TOUCHSCREEN_W90X900) += w90p910_ts.o
+obj-$(CONFIG_TOUCHSCREEN_TPS6507X) += tps6507x-ts.o
diff --git a/drivers/input/touchscreen/tps6507x-ts.c b/drivers/input/touchscreen/tps6507x-ts.c
new file mode 100644
index 0000000..5de80a1
--- /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@xxxxxxxxxxxx)
+ *
+ * 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@xxxxxxxxxxxx>");
+MODULE_DESCRIPTION("TPS6507x - TouchScreen driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:tps6507x-tsc");
diff --git a/drivers/mfd/tps6507x.c b/drivers/mfd/tps6507x.c
index edda9ff..d05c52d 100644
--- a/drivers/mfd/tps6507x.c
+++ b/drivers/mfd/tps6507x.c
@@ -25,6 +25,9 @@ static struct mfd_cell tps6507x_devs[] = {
{
.name = "tps6507x-pmic",
},
+ {
+ .name = "tps6507x-ts",
+ },
};
diff --git a/include/linux/input/tps6507x-ts.h b/include/linux/input/tps6507x-ts.h
new file mode 100644
index 0000000..ab14403
--- /dev/null
+++ b/include/linux/input/tps6507x-ts.h
@@ -0,0 +1,24 @@
+/* linux/i2c/tps6507x-ts.h
+ *
+ * Functions to access TPS65070 touch screen chip.
+ *
+ * Copyright (c) 2009 RidgeRun (todd.fischer@xxxxxxxxxxxx)
+ *
+ *
+ * For licencing details see kernel-base/COPYING
+ */
+
+#ifndef __LINUX_I2C_TPS6507X_TS_H
+#define __LINUX_I2C_TPS6507X_TS_H
+
+/* Board specific touch screen initial values */
+struct touchscreen_init_data {
+ int poll_period; /* ms */
+ int vref; /* non-zero to leave vref on */
+ __u16 min_pressure; /* min reading to be treated as a touch */
+ __u16 vendor;
+ __u16 product;
+ __u16 version;
+};
+
+#endif /* __LINUX_I2C_TPS6507X_TS_H */
diff --git a/include/linux/mfd/tps6507x.h b/include/linux/mfd/tps6507x.h
index 9543cb7..c923e48 100644
--- a/include/linux/mfd/tps6507x.h
+++ b/include/linux/mfd/tps6507x.h
@@ -142,6 +142,7 @@
struct tps6507x_board {
struct regulator_init_data *tps6507x_pmic_init_data;
+ struct touchscreen_init_data *tps6507x_ts_init_data;
};
/**
@@ -162,6 +163,7 @@ struct tps6507x_dev {
/* Client devices */
struct tps6507x_pmic *pmic;
+ struct tps6507x_ts *ts;
};
#endif /* __LINUX_MFD_TPS6507X_H */
--
1.6.0.4
--
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