--- /dev/null
- static int __devinit titsc_probe(struct platform_device *pdev)
+/*
+ * TI Touch Screen driver
+ *
+ * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation version 2.
+ *
+ * This program is distributed "as is" WITHOUT ANY WARRANTY of any
+ * kind, whether express or implied; without even the implied warranty
+ * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/input.h>
+#include <linux/slab.h>
+#include <linux/interrupt.h>
+#include <linux/clk.h>
+#include <linux/platform_device.h>
+#include <linux/io.h>
+#include <linux/input/ti_am335x_tsc.h>
+#include <linux/delay.h>
+
+#include <linux/mfd/ti_am335x_tscadc.h>
+
+#define ADCFSM_STEPID 0x10
+#define SEQ_SETTLE 275
+#define MAX_12BIT ((1 << 12) - 1)
+
+struct titsc {
+ struct input_dev *input;
+ struct ti_tscadc_dev *mfd_tscadc;
+ unsigned int irq;
+ unsigned int wires;
+ unsigned int x_plate_resistance;
+ bool pen_down;
+ int steps_to_configure;
+};
+
+static unsigned int titsc_readl(struct titsc *ts, unsigned int reg)
+{
+ return readl(ts->mfd_tscadc->tscadc_base + reg);
+}
+
+static void titsc_writel(struct titsc *tsc, unsigned int reg,
+ unsigned int val)
+{
+ writel(val, tsc->mfd_tscadc->tscadc_base + reg);
+}
+
+static void titsc_step_config(struct titsc *ts_dev)
+{
+ unsigned int config;
+ int i, total_steps;
+
+ /* Configure the Step registers */
+ total_steps = 2 * ts_dev->steps_to_configure;
+
+ config = STEPCONFIG_MODE_HWSYNC |
+ STEPCONFIG_AVG_16 | STEPCONFIG_XPP;
+ switch (ts_dev->wires) {
+ case 4:
+ config |= STEPCONFIG_INP_AN2 | STEPCONFIG_XNN;
+ break;
+ case 5:
+ config |= STEPCONFIG_YNN |
+ STEPCONFIG_INP_AN4 | STEPCONFIG_XNN |
+ STEPCONFIG_YPP;
+ break;
+ case 8:
+ config |= STEPCONFIG_INP_AN2 | STEPCONFIG_XNN;
+ break;
+ }
+
+ for (i = 1; i <= ts_dev->steps_to_configure; i++) {
+ titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
+ titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
+ }
+
+ config = 0;
+ config = STEPCONFIG_MODE_HWSYNC |
+ STEPCONFIG_AVG_16 | STEPCONFIG_YNN |
+ STEPCONFIG_INM_ADCREFM | STEPCONFIG_FIFO1;
+ switch (ts_dev->wires) {
+ case 4:
+ config |= STEPCONFIG_YPP;
+ break;
+ case 5:
+ config |= STEPCONFIG_XPP | STEPCONFIG_INP_AN4 |
+ STEPCONFIG_XNP | STEPCONFIG_YPN;
+ break;
+ case 8:
+ config |= STEPCONFIG_YPP;
+ break;
+ }
+
+ for (i = (ts_dev->steps_to_configure + 1); i <= total_steps; i++) {
+ titsc_writel(ts_dev, REG_STEPCONFIG(i), config);
+ titsc_writel(ts_dev, REG_STEPDELAY(i), STEPCONFIG_OPENDLY);
+ }
+
+ config = 0;
+ /* Charge step configuration */
+ config = STEPCONFIG_XPP | STEPCONFIG_YNN |
+ STEPCHARGE_RFP_XPUL | STEPCHARGE_RFM_XNUR |
+ STEPCHARGE_INM_AN1 | STEPCHARGE_INP_AN1;
+
+ titsc_writel(ts_dev, REG_CHARGECONFIG, config);
+ titsc_writel(ts_dev, REG_CHARGEDELAY, CHARGEDLY_OPENDLY);
+
+ config = 0;
+ /* Configure to calculate pressure */
+ config = STEPCONFIG_MODE_HWSYNC |
+ STEPCONFIG_AVG_16 | STEPCONFIG_YPP |
+ STEPCONFIG_XNN | STEPCONFIG_INM_ADCREFM;
+ titsc_writel(ts_dev, REG_STEPCONFIG(total_steps + 1), config);
+ titsc_writel(ts_dev, REG_STEPDELAY(total_steps + 1),
+ STEPCONFIG_OPENDLY);
+
+ config |= STEPCONFIG_INP_AN3 | STEPCONFIG_FIFO1;
+ titsc_writel(ts_dev, REG_STEPCONFIG(total_steps + 2), config);
+ titsc_writel(ts_dev, REG_STEPDELAY(total_steps + 2),
+ STEPCONFIG_OPENDLY);
+
+ titsc_writel(ts_dev, REG_SE, STPENB_STEPENB_TC);
+}
+
+static void titsc_read_coordinates(struct titsc *ts_dev,
+ unsigned int *x, unsigned int *y)
+{
+ unsigned int fifocount = titsc_readl(ts_dev, REG_FIFO0CNT);
+ unsigned int prev_val_x = ~0, prev_val_y = ~0;
+ unsigned int prev_diff_x = ~0, prev_diff_y = ~0;
+ unsigned int read, diff;
+ unsigned int i, channel;
+
+ /*
+ * Delta filter is used to remove large variations in sampled
+ * values from ADC. The filter tries to predict where the next
+ * coordinate could be. This is done by taking a previous
+ * coordinate and subtracting it form current one. Further the
+ * algorithm compares the difference with that of a present value,
+ * if true the value is reported to the sub system.
+ */
+ for (i = 0; i < fifocount - 1; i++) {
+ read = titsc_readl(ts_dev, REG_FIFO0);
+ channel = read & 0xf0000;
+ channel = channel >> 0x10;
+ if ((channel >= 0) && (channel < ts_dev->steps_to_configure)) {
+ read &= 0xfff;
+ diff = abs(read - prev_val_x);
+ if (diff < prev_diff_x) {
+ prev_diff_x = diff;
+ *x = read;
+ }
+ prev_val_x = read;
+ }
+
+ read = titsc_readl(ts_dev, REG_FIFO1);
+ channel = read & 0xf0000;
+ channel = channel >> 0x10;
+ if ((channel >= ts_dev->steps_to_configure) &&
+ (channel < (2 * ts_dev->steps_to_configure - 1))) {
+ read &= 0xfff;
+ diff = abs(read - prev_val_y);
+ if (diff < prev_diff_y) {
+ prev_diff_y = diff;
+ *y = read;
+ }
+ prev_val_y = read;
+ }
+ }
+}
+
+static irqreturn_t titsc_irq(int irq, void *dev)
+{
+ struct titsc *ts_dev = dev;
+ struct input_dev *input_dev = ts_dev->input;
+ unsigned int status, irqclr = 0;
+ unsigned int x = 0, y = 0;
+ unsigned int z1, z2, z;
+ unsigned int fsm;
+ unsigned int fifo1count, fifo0count;
+ int i;
+
+ status = titsc_readl(ts_dev, REG_IRQSTATUS);
+ if (status & IRQENB_FIFO0THRES) {
+ titsc_read_coordinates(ts_dev, &x, &y);
+
+ z1 = titsc_readl(ts_dev, REG_FIFO0) & 0xfff;
+ z2 = titsc_readl(ts_dev, REG_FIFO1) & 0xfff;
+
+ fifo1count = titsc_readl(ts_dev, REG_FIFO1CNT);
+ for (i = 0; i < fifo1count; i++)
+ titsc_readl(ts_dev, REG_FIFO1);
+
+ fifo0count = titsc_readl(ts_dev, REG_FIFO0CNT);
+ for (i = 0; i < fifo0count; i++)
+ titsc_readl(ts_dev, REG_FIFO0);
+
+ if (ts_dev->pen_down && z1 != 0 && z2 != 0) {
+ /*
+ * Calculate pressure using formula
+ * Resistance(touch) = x plate resistance *
+ * x postion/4096 * ((z2 / z1) - 1)
+ */
+ z = z2 - z1;
+ z *= x;
+ z *= ts_dev->x_plate_resistance;
+ z /= z1;
+ z = (z + 2047) >> 12;
+
+ if (z <= MAX_12BIT) {
+ input_report_abs(input_dev, ABS_X, x);
+ input_report_abs(input_dev, ABS_Y, y);
+ input_report_abs(input_dev, ABS_PRESSURE, z);
+ input_report_key(input_dev, BTN_TOUCH, 1);
+ input_sync(input_dev);
+ }
+ }
+ irqclr |= IRQENB_FIFO0THRES;
+ }
+
+ /*
+ * Time for sequencer to settle, to read
+ * correct state of the sequencer.
+ */
+ udelay(SEQ_SETTLE);
+
+ status = titsc_readl(ts_dev, REG_RAWIRQSTATUS);
+ if (status & IRQENB_PENUP) {
+ /* Pen up event */
+ fsm = titsc_readl(ts_dev, REG_ADCFSM);
+ if (fsm == ADCFSM_STEPID) {
+ ts_dev->pen_down = false;
+ input_report_key(input_dev, BTN_TOUCH, 0);
+ input_report_abs(input_dev, ABS_PRESSURE, 0);
+ input_sync(input_dev);
+ } else {
+ ts_dev->pen_down = true;
+ }
+ irqclr |= IRQENB_PENUP;
+ }
+
+ titsc_writel(ts_dev, REG_IRQSTATUS, irqclr);
+
+ titsc_writel(ts_dev, REG_SE, STPENB_STEPENB_TC);
+ return IRQ_HANDLED;
+}
+
+/*
+ * The functions for inserting/removing driver as a module.
+ */
+
- static int __devexit titsc_remove(struct platform_device *pdev)
++static int titsc_probe(struct platform_device *pdev)
+{
+ struct titsc *ts_dev;
+ struct input_dev *input_dev;
+ struct ti_tscadc_dev *tscadc_dev = pdev->dev.platform_data;
+ struct mfd_tscadc_board *pdata;
+ int err;
+
+ pdata = tscadc_dev->dev->platform_data;
+
+ if (!pdata) {
+ dev_err(&pdev->dev, "Could not find platform data\n");
+ return -EINVAL;
+ }
+
+ /* Allocate memory for device */
+ ts_dev = kzalloc(sizeof(struct titsc), GFP_KERNEL);
+ input_dev = input_allocate_device();
+ if (!ts_dev || !input_dev) {
+ dev_err(&pdev->dev, "failed to allocate memory.\n");
+ err = -ENOMEM;
+ goto err_free_mem;
+ }
+
+ tscadc_dev->tsc = ts_dev;
+ ts_dev->mfd_tscadc = tscadc_dev;
+ ts_dev->input = input_dev;
+ ts_dev->irq = tscadc_dev->irq;
+ ts_dev->wires = pdata->tsc_init->wires;
+ ts_dev->x_plate_resistance = pdata->tsc_init->x_plate_resistance;
+ ts_dev->steps_to_configure = pdata->tsc_init->steps_to_configure;
+
+ err = request_irq(ts_dev->irq, titsc_irq,
+ 0, pdev->dev.driver->name, ts_dev);
+ if (err) {
+ dev_err(&pdev->dev, "failed to allocate irq.\n");
+ goto err_free_mem;
+ }
+
+ titsc_writel(ts_dev, REG_IRQENABLE, IRQENB_FIFO0THRES);
+ titsc_step_config(ts_dev);
+ titsc_writel(ts_dev, REG_FIFO0THR, ts_dev->steps_to_configure);
+
+ input_dev->name = "ti-tsc";
+ input_dev->dev.parent = &pdev->dev;
+
+ 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_12BIT, 0, 0);
+ input_set_abs_params(input_dev, ABS_Y, 0, MAX_12BIT, 0, 0);
+ input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_12BIT, 0, 0);
+
+ /* register to the input system */
+ err = input_register_device(input_dev);
+ if (err)
+ goto err_free_irq;
+
+ platform_set_drvdata(pdev, ts_dev);
+ return 0;
+
+err_free_irq:
+ free_irq(ts_dev->irq, ts_dev);
+err_free_mem:
+ input_free_device(input_dev);
+ kfree(ts_dev);
+ return err;
+}
+
- .remove = __devexit_p(titsc_remove),
++static int titsc_remove(struct platform_device *pdev)
+{
+ struct ti_tscadc_dev *tscadc_dev = pdev->dev.platform_data;
+ struct titsc *ts_dev = tscadc_dev->tsc;
+
+ free_irq(ts_dev->irq, ts_dev);
+
+ input_unregister_device(ts_dev->input);
+
+ platform_set_drvdata(pdev, NULL);
+ kfree(ts_dev);
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int titsc_suspend(struct device *dev)
+{
+ struct ti_tscadc_dev *tscadc_dev = dev->platform_data;
+ struct titsc *ts_dev = tscadc_dev->tsc;
+ unsigned int idle;
+
+ if (device_may_wakeup(tscadc_dev->dev)) {
+ idle = titsc_readl(ts_dev, REG_IRQENABLE);
+ titsc_writel(ts_dev, REG_IRQENABLE,
+ (idle | IRQENB_HW_PEN));
+ titsc_writel(ts_dev, REG_IRQWAKEUP, IRQWKUP_ENB);
+ }
+ return 0;
+}
+
+static int titsc_resume(struct device *dev)
+{
+ struct ti_tscadc_dev *tscadc_dev = dev->platform_data;
+ struct titsc *ts_dev = tscadc_dev->tsc;
+
+ if (device_may_wakeup(tscadc_dev->dev)) {
+ titsc_writel(ts_dev, REG_IRQWAKEUP,
+ 0x00);
+ titsc_writel(ts_dev, REG_IRQCLR, IRQENB_HW_PEN);
+ }
+ titsc_step_config(ts_dev);
+ titsc_writel(ts_dev, REG_FIFO0THR,
+ ts_dev->steps_to_configure);
+ return 0;
+}
+
+static const struct dev_pm_ops titsc_pm_ops = {
+ .suspend = titsc_suspend,
+ .resume = titsc_resume,
+};
+#define TITSC_PM_OPS (&titsc_pm_ops)
+#else
+#define TITSC_PM_OPS NULL
+#endif
+
+static struct platform_driver ti_tsc_driver = {
+ .probe = titsc_probe,
++ .remove = titsc_remove,
+ .driver = {
+ .name = "tsc",
+ .owner = THIS_MODULE,
+ .pm = TITSC_PM_OPS,
+ },
+};
+module_platform_driver(ti_tsc_driver);
+
+MODULE_DESCRIPTION("TI touchscreen controller driver");
+MODULE_AUTHOR("Rachna Patil <rachna@ti.com>");
+MODULE_LICENSE("GPL");