linux/drivers/input/touchscreen/88pm860x-ts.c
Johan Hovold 906bf7daa0 Input: 88pm860x-ts - fix child-node lookup
Fix child node-lookup during probe, which ended up searching the whole
device tree depth-first starting at parent rather than just matching on
its children.

To make things worse, the parent node was prematurely freed, while the
child node was leaked.

Fixes: 2e57d56747 ("mfd: 88pm860x: Device tree support")
Cc: stable <stable@vger.kernel.org>     # 3.7
Signed-off-by: Johan Hovold <johan@kernel.org>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2018-01-08 17:40:59 -08:00

310 lines
8.3 KiB
C

/*
* Touchscreen driver for Marvell 88PM860x
*
* Copyright (C) 2009 Marvell International Ltd.
* Haojian Zhuang <haojian.zhuang@marvell.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/platform_device.h>
#include <linux/i2c.h>
#include <linux/input.h>
#include <linux/mfd/88pm860x.h>
#include <linux/slab.h>
#include <linux/device.h>
#define MEAS_LEN (8)
#define ACCURATE_BIT (12)
/* touch register */
#define MEAS_EN3 (0x52)
#define MEAS_TSIX_1 (0x8D)
#define MEAS_TSIX_2 (0x8E)
#define MEAS_TSIY_1 (0x8F)
#define MEAS_TSIY_2 (0x90)
#define MEAS_TSIZ1_1 (0x91)
#define MEAS_TSIZ1_2 (0x92)
#define MEAS_TSIZ2_1 (0x93)
#define MEAS_TSIZ2_2 (0x94)
/* bit definitions of touch */
#define MEAS_PD_EN (1 << 3)
#define MEAS_TSIX_EN (1 << 4)
#define MEAS_TSIY_EN (1 << 5)
#define MEAS_TSIZ1_EN (1 << 6)
#define MEAS_TSIZ2_EN (1 << 7)
struct pm860x_touch {
struct input_dev *idev;
struct i2c_client *i2c;
struct pm860x_chip *chip;
int irq;
int res_x; /* resistor of Xplate */
};
static irqreturn_t pm860x_touch_handler(int irq, void *data)
{
struct pm860x_touch *touch = data;
struct pm860x_chip *chip = touch->chip;
unsigned char buf[MEAS_LEN];
int x, y, pen_down;
int z1, z2, rt = 0;
int ret;
ret = pm860x_bulk_read(touch->i2c, MEAS_TSIX_1, MEAS_LEN, buf);
if (ret < 0)
goto out;
pen_down = buf[1] & (1 << 6);
x = ((buf[0] & 0xFF) << 4) | (buf[1] & 0x0F);
y = ((buf[2] & 0xFF) << 4) | (buf[3] & 0x0F);
z1 = ((buf[4] & 0xFF) << 4) | (buf[5] & 0x0F);
z2 = ((buf[6] & 0xFF) << 4) | (buf[7] & 0x0F);
if (pen_down) {
if ((x != 0) && (z1 != 0) && (touch->res_x != 0)) {
rt = z2 / z1 - 1;
rt = (rt * touch->res_x * x) >> ACCURATE_BIT;
dev_dbg(chip->dev, "z1:%d, z2:%d, rt:%d\n",
z1, z2, rt);
}
input_report_abs(touch->idev, ABS_X, x);
input_report_abs(touch->idev, ABS_Y, y);
input_report_abs(touch->idev, ABS_PRESSURE, rt);
input_report_key(touch->idev, BTN_TOUCH, 1);
dev_dbg(chip->dev, "pen down at [%d, %d].\n", x, y);
} else {
input_report_abs(touch->idev, ABS_PRESSURE, 0);
input_report_key(touch->idev, BTN_TOUCH, 0);
dev_dbg(chip->dev, "pen release\n");
}
input_sync(touch->idev);
out:
return IRQ_HANDLED;
}
static int pm860x_touch_open(struct input_dev *dev)
{
struct pm860x_touch *touch = input_get_drvdata(dev);
int data, ret;
data = MEAS_PD_EN | MEAS_TSIX_EN | MEAS_TSIY_EN
| MEAS_TSIZ1_EN | MEAS_TSIZ2_EN;
ret = pm860x_set_bits(touch->i2c, MEAS_EN3, data, data);
if (ret < 0)
goto out;
return 0;
out:
return ret;
}
static void pm860x_touch_close(struct input_dev *dev)
{
struct pm860x_touch *touch = input_get_drvdata(dev);
int data;
data = MEAS_PD_EN | MEAS_TSIX_EN | MEAS_TSIY_EN
| MEAS_TSIZ1_EN | MEAS_TSIZ2_EN;
pm860x_set_bits(touch->i2c, MEAS_EN3, data, 0);
}
#ifdef CONFIG_OF
static int pm860x_touch_dt_init(struct platform_device *pdev,
struct pm860x_chip *chip,
int *res_x)
{
struct device_node *np = pdev->dev.parent->of_node;
struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
: chip->companion;
int data, n, ret;
if (!np)
return -ENODEV;
np = of_get_child_by_name(np, "touch");
if (!np) {
dev_err(&pdev->dev, "Can't find touch node\n");
return -EINVAL;
}
/* set GPADC MISC1 register */
data = 0;
if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-prebias", &n))
data |= (n << 1) & PM8607_GPADC_PREBIAS_MASK;
if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-slot-cycle", &n))
data |= (n << 3) & PM8607_GPADC_SLOT_CYCLE_MASK;
if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-off-scale", &n))
data |= (n << 5) & PM8607_GPADC_OFF_SCALE_MASK;
if (!of_property_read_u32(np, "marvell,88pm860x-gpadc-sw-cal", &n))
data |= (n << 7) & PM8607_GPADC_SW_CAL_MASK;
if (data) {
ret = pm860x_reg_write(i2c, PM8607_GPADC_MISC1, data);
if (ret < 0)
goto err_put_node;
}
/* set tsi prebias time */
if (!of_property_read_u32(np, "marvell,88pm860x-tsi-prebias", &data)) {
ret = pm860x_reg_write(i2c, PM8607_TSI_PREBIAS, data);
if (ret < 0)
goto err_put_node;
}
/* set prebias & prechg time of pen detect */
data = 0;
if (!of_property_read_u32(np, "marvell,88pm860x-pen-prebias", &n))
data |= n & PM8607_PD_PREBIAS_MASK;
if (!of_property_read_u32(np, "marvell,88pm860x-pen-prechg", &n))
data |= n & PM8607_PD_PRECHG_MASK;
if (data) {
ret = pm860x_reg_write(i2c, PM8607_PD_PREBIAS, data);
if (ret < 0)
goto err_put_node;
}
of_property_read_u32(np, "marvell,88pm860x-resistor-X", res_x);
of_node_put(np);
return 0;
err_put_node:
of_node_put(np);
return -EINVAL;
}
#else
#define pm860x_touch_dt_init(x, y, z) (-1)
#endif
static int pm860x_touch_probe(struct platform_device *pdev)
{
struct pm860x_chip *chip = dev_get_drvdata(pdev->dev.parent);
struct pm860x_touch_pdata *pdata = dev_get_platdata(&pdev->dev);
struct pm860x_touch *touch;
struct i2c_client *i2c = (chip->id == CHIP_PM8607) ? chip->client \
: chip->companion;
int irq, ret, res_x = 0, data = 0;
irq = platform_get_irq(pdev, 0);
if (irq < 0) {
dev_err(&pdev->dev, "No IRQ resource!\n");
return -EINVAL;
}
if (pm860x_touch_dt_init(pdev, chip, &res_x)) {
if (pdata) {
/* set GPADC MISC1 register */
data = 0;
data |= (pdata->gpadc_prebias << 1)
& PM8607_GPADC_PREBIAS_MASK;
data |= (pdata->slot_cycle << 3)
& PM8607_GPADC_SLOT_CYCLE_MASK;
data |= (pdata->off_scale << 5)
& PM8607_GPADC_OFF_SCALE_MASK;
data |= (pdata->sw_cal << 7)
& PM8607_GPADC_SW_CAL_MASK;
if (data) {
ret = pm860x_reg_write(i2c,
PM8607_GPADC_MISC1, data);
if (ret < 0)
return -EINVAL;
}
/* set tsi prebias time */
if (pdata->tsi_prebias) {
data = pdata->tsi_prebias;
ret = pm860x_reg_write(i2c,
PM8607_TSI_PREBIAS, data);
if (ret < 0)
return -EINVAL;
}
/* set prebias & prechg time of pen detect */
data = 0;
data |= pdata->pen_prebias
& PM8607_PD_PREBIAS_MASK;
data |= (pdata->pen_prechg << 5)
& PM8607_PD_PRECHG_MASK;
if (data) {
ret = pm860x_reg_write(i2c,
PM8607_PD_PREBIAS, data);
if (ret < 0)
return -EINVAL;
}
res_x = pdata->res_x;
} else {
dev_err(&pdev->dev, "failed to get platform data\n");
return -EINVAL;
}
}
/* enable GPADC */
ret = pm860x_set_bits(i2c, PM8607_GPADC_MISC1, PM8607_GPADC_EN,
PM8607_GPADC_EN);
if (ret)
return ret;
touch = devm_kzalloc(&pdev->dev, sizeof(struct pm860x_touch),
GFP_KERNEL);
if (!touch)
return -ENOMEM;
touch->idev = devm_input_allocate_device(&pdev->dev);
if (!touch->idev) {
dev_err(&pdev->dev, "Failed to allocate input device!\n");
return -ENOMEM;
}
touch->idev->name = "88pm860x-touch";
touch->idev->phys = "88pm860x/input0";
touch->idev->id.bustype = BUS_I2C;
touch->idev->dev.parent = &pdev->dev;
touch->idev->open = pm860x_touch_open;
touch->idev->close = pm860x_touch_close;
touch->chip = chip;
touch->i2c = i2c;
touch->irq = irq;
touch->res_x = res_x;
input_set_drvdata(touch->idev, touch);
ret = devm_request_threaded_irq(&pdev->dev, touch->irq, NULL,
pm860x_touch_handler, IRQF_ONESHOT,
"touch", touch);
if (ret < 0)
return ret;
__set_bit(EV_ABS, touch->idev->evbit);
__set_bit(ABS_X, touch->idev->absbit);
__set_bit(ABS_Y, touch->idev->absbit);
__set_bit(ABS_PRESSURE, touch->idev->absbit);
__set_bit(EV_SYN, touch->idev->evbit);
__set_bit(EV_KEY, touch->idev->evbit);
__set_bit(BTN_TOUCH, touch->idev->keybit);
input_set_abs_params(touch->idev, ABS_X, 0, 1 << ACCURATE_BIT, 0, 0);
input_set_abs_params(touch->idev, ABS_Y, 0, 1 << ACCURATE_BIT, 0, 0);
input_set_abs_params(touch->idev, ABS_PRESSURE, 0, 1 << ACCURATE_BIT,
0, 0);
ret = input_register_device(touch->idev);
if (ret < 0) {
dev_err(chip->dev, "Failed to register touch!\n");
return ret;
}
return 0;
}
static struct platform_driver pm860x_touch_driver = {
.driver = {
.name = "88pm860x-touch",
},
.probe = pm860x_touch_probe,
};
module_platform_driver(pm860x_touch_driver);
MODULE_DESCRIPTION("Touchscreen driver for Marvell Semiconductor 88PM860x");
MODULE_AUTHOR("Haojian Zhuang <haojian.zhuang@marvell.com>");
MODULE_LICENSE("GPL");
MODULE_ALIAS("platform:88pm860x-touch");