---
Changes since v2:
- do not free driver data and irq on remove (since we are using devm now)
Changes since v1:
- Move device tree parsing to main driver file ad7879.c
- Use common touchscreen_parse_properties for common properties
- Use device_property_* API
- Use struct ad7879 directly to store parsed values
- Support SPI variant through device tree too (untested)
- Add vendor prefix to vendor specific dt properties
.../bindings/input/touchscreen/ad7879.txt | 53 ++++++++
drivers/input/touchscreen/ad7879-i2c.c | 10 ++
drivers/input/touchscreen/ad7879-spi.c | 10 ++
drivers/input/touchscreen/ad7879.c | 145 +++++++++++++--------
4 files changed, 161 insertions(+), 57 deletions(-)
create mode 100644 Documentation/devicetree/bindings/input/touchscreen/ad7879.txt
diff --git a/Documentation/devicetree/bindings/input/touchscreen/ad7879.txt b/Documentation/devicetree/bindings/input/touchscreen/ad7879.txt
new file mode 100644
index 0000000..e3f22d2
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/touchscreen/ad7879.txt
@@ -0,0 +1,53 @@
+* Analog Devices AD7879(-1)/AD7889(-1) touchscreen interface (SPI/I2C)
+
+Required properties:
+- compatible : for SPI slave, use "adi,ad7879"
+ for I2C slave, use "adi,ad7879-1"
+- reg : SPI chipselect/I2C slave address
+ See spi-bus.txt for more SPI slave properties
+- interrupt-parent : the phandle for the interrupt controller
+- interrupts : touch controller interrupt
+- touchscreen-max-pressure : maximum reported pressure
+- adi,resistance-plate-x : total resistance of X-plate (for pressure
+ calculation)
+Optional properties:
+- touchscreen-swapped-x-y : X and Y axis are swapped (boolean)
+- adi,first-conversion-delay : 0-12: In 128us steps (starting with 128us)
+ 13 : 2.560ms
+ 14 : 3.584ms
+ 15 : 4.096ms
+ This property has to be a '/bits/ 8' value
+- adi,acquisition-time : 0: 2us
+ 1: 4us
+ 2: 8us
+ 3: 16us
+ This property has to be a '/bits/ 8' value
+- adi,median-filter-size : 0: disabled
+ 1: 4 measurements
+ 2: 8 measurements
+ 3: 16 measurements
+ This property has to be a '/bits/ 8' value
+- adi,averaging : 0: 2 middle values (1 if median disabled)
+ 1: 4 middle values
+ 2: 8 middle values
+ 3: 16 values
+ This property has to be a '/bits/ 8' value
+- adi,conversion-interval: : 0 : convert one time only
+ 1-255: 515us + val * 35us (up to 9.440ms)
+ This property has to be a '/bits/ 8' value
+
+Example:
+
+ ad7879@2c {
+ compatible = "adi,ad7879-1";
+ reg = <0x2c>;
+ interrupt-parent = <&gpio1>;
+ interrupts = <13 IRQ_TYPE_EDGE_FALLING>;
+ touchscreen-max-pressure = <4096>;
+ adi,resistance-plate-x = <120>;
+ adi,first-conversion-delay = /bits/ 8 <3>;
+ adi,acquisition-time = /bits/ 8 <1>;
+ adi,median-filter-size = /bits/ 8 <2>;
+ adi,averaging = /bits/ 8 <1>;
+ adi,conversion-interval = /bits/ 8 <255>;
+ };
diff --git a/drivers/input/touchscreen/ad7879-i2c.c b/drivers/input/touchscreen/ad7879-i2c.c
index d66962c..58f72e0 100644
--- a/drivers/input/touchscreen/ad7879-i2c.c
+++ b/drivers/input/touchscreen/ad7879-i2c.c
@@ -10,6 +10,7 @@
#include <linux/i2c.h>
#include <linux/module.h>
#include <linux/types.h>
+#include <linux/of.h>
#include <linux/pm.h>
#include "ad7879.h"
@@ -91,10 +92,19 @@ static const struct i2c_device_id ad7879_id[] = {
};
MODULE_DEVICE_TABLE(i2c, ad7879_id);
+#ifdef CONFIG_OF
+static const struct of_device_id ad7879_i2c_dt_ids[] = {
+ { .compatible = "adi,ad7879-1", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ad7879_i2c_dt_ids);
+#endif
+
static struct i2c_driver ad7879_i2c_driver = {
.driver = {
.name = "ad7879",
.pm = &ad7879_pm_ops,
+ .of_match_table = of_match_ptr(ad7879_i2c_dt_ids),
},
.probe = ad7879_i2c_probe,
.remove = ad7879_i2c_remove,
diff --git a/drivers/input/touchscreen/ad7879-spi.c b/drivers/input/touchscreen/ad7879-spi.c
index 48033c2..d42b6b9 100644
--- a/drivers/input/touchscreen/ad7879-spi.c
+++ b/drivers/input/touchscreen/ad7879-spi.c
@@ -10,6 +10,7 @@
#include <linux/pm.h>
#include <linux/spi/spi.h>
#include <linux/module.h>
+#include <linux/of.h>
#include "ad7879.h"
@@ -146,10 +147,19 @@ static int ad7879_spi_remove(struct spi_device *spi)
return 0;
}
+#ifdef CONFIG_OF
+static const struct of_device_id ad7879_spi_dt_ids[] = {
+ { .compatible = "adi,ad7879", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, ad7879_spi_dt_ids);
+#endif
+
static struct spi_driver ad7879_spi_driver = {
.driver = {
.name = "ad7879",
.pm = &ad7879_pm_ops,
+ .of_match_table = of_match_ptr(ad7879_spi_dt_ids),
},
.probe = ad7879_spi_probe,
.remove = ad7879_spi_remove,
diff --git a/drivers/input/touchscreen/ad7879.c b/drivers/input/touchscreen/ad7879.c
index abd0220..093cb04 100644
--- a/drivers/input/touchscreen/ad7879.c
+++ b/drivers/input/touchscreen/ad7879.c
@@ -31,6 +31,7 @@
#include <linux/i2c.h>
#include <linux/gpio.h>
+#include <linux/input/touchscreen.h>
#include <linux/platform_data/ad7879.h>
#include <linux/module.h>
#include "ad7879.h"
@@ -126,7 +127,6 @@ struct ad7879 {
u8 pen_down_acc_interval;
u8 median;
u16 x_plate_ohms;
- u16 pressure_max;
u16 cmd_crtl1;
u16 cmd_crtl2;
u16 cmd_crtl3;
@@ -186,7 +186,7 @@ static int ad7879_report(struct ad7879 *ts)
* Sample found inconsistent, pressure is beyond
* the maximum. Don't report it to user space.
*/
- if (Rt > ts->pressure_max)
+ if (Rt > input_abs_get_max(input_dev, ABS_PRESSURE))
return -EINVAL;
/*
@@ -469,7 +469,7 @@ static void ad7879_gpio_remove(struct ad7879 *ts)
{
const struct ad7879_platform_data *pdata = dev_get_platdata(ts->dev);
- if (pdata->gpio_export)
+ if (pdata && pdata->gpio_export)
gpiochip_remove(&ts->gc);
}
@@ -485,6 +485,29 @@ static inline void ad7879_gpio_remove(struct ad7879 *ts)
}
#endif
+static int ad7879_parse_dt(struct device *dev, struct ad7879 *ts)
+{
+ int err;
+ u32 tmp;
+
+ err = device_property_read_u32(dev, "adi,resistance-plate-x", &tmp);
+ if (err) {
+ dev_err(dev, "failed to get resistance-plate-x property\n");
+ return err;
+ }
+ ts->x_plate_ohms = (u16)tmp;
+
+ device_property_read_u8(dev, "adi,first-conversion-delay", &ts->first_conversion_delay);
+ device_property_read_u8(dev, "adi,acquisition-time", &ts->acquisition_time);
+ device_property_read_u8(dev, "adi,median-filter-size", &ts->median);
+ device_property_read_u8(dev, "adi,averaging", &ts->averaging);
+ device_property_read_u8(dev, "adi,conversion-interval", &ts->pen_down_acc_interval);
+
+ ts->swap_xy = device_property_read_bool(dev, "touchscreen-swapped-x-y");
+
+ return 0;
+}
+
struct ad7879 *ad7879_probe(struct device *dev, u8 devid, unsigned int irq,
const struct ad7879_bus_ops *bops)
{
@@ -495,22 +518,37 @@ struct ad7879 *ad7879_probe(struct device *dev, u8 devid, unsigned int irq,
u16 revid;
if (!irq) {
- dev_err(dev, "no IRQ?\n");
- err = -EINVAL;
- goto err_out;
+ dev_err(dev, "No IRQ specified\n");
+ return ERR_PTR(-EINVAL);
}
- if (!pdata) {
- dev_err(dev, "no platform data?\n");
- err = -EINVAL;
- goto err_out;
+ ts = devm_kzalloc(dev, sizeof(*ts), GFP_KERNEL);
+ if (!ts)
+ return ERR_PTR(-ENOMEM);
+
+ if (pdata) {
+ /* Platform data use swapped axis (backward compatibility) */
+ ts->swap_xy = !pdata->swap_xy;
+
+ ts->x_plate_ohms = pdata->x_plate_ohms ? : 400;
+
+ ts->first_conversion_delay = pdata->first_conversion_delay;
+ ts->acquisition_time = pdata->acquisition_time;
+ ts->averaging = pdata->averaging;
+ ts->pen_down_acc_interval = pdata->pen_down_acc_interval;
+ ts->median = pdata->median;
+
+ } else if (dev->of_node) {
+ ad7879_parse_dt(dev, ts);
+ } else {
+ dev_err(dev, "No platform data\n");
+ return ERR_PTR(-EINVAL);
}
- ts = kzalloc(sizeof(*ts), GFP_KERNEL);
- input_dev = input_allocate_device();
- if (!ts || !input_dev) {
- err = -ENOMEM;
- goto err_free_mem;
+ input_dev = devm_input_allocate_device(dev);
+ if (!input_dev) {
+ dev_err(dev, "Failed to allocate input device\n");
+ return ERR_PTR(-ENOMEM);
}
ts->bops = bops;
@@ -518,20 +556,7 @@ struct ad7879 *ad7879_probe(struct device *dev, u8 devid, unsigned int irq,
ts->input = input_dev;
ts->irq = irq;
- /* Use swapped axis by default (backward compatibility) */
- ts->swap_xy = !pdata->swap_xy;
-
setup_timer(&ts->timer, ad7879_timer, (unsigned long) ts);
-
- ts->x_plate_ohms = pdata->x_plate_ohms ? : 400;
- ts->pressure_max = pdata->pressure_max ? : ~0;
-
- ts->first_conversion_delay = pdata->first_conversion_delay;
- ts->acquisition_time = pdata->acquisition_time;
- ts->averaging = pdata->averaging;
- ts->pen_down_acc_interval = pdata->pen_down_acc_interval;
- ts->median = pdata->median;
-
snprintf(ts->phys, sizeof(ts->phys), "%s/input0", dev_name(dev));
input_dev->name = "AD7879 Touchscreen";
@@ -552,21 +577,33 @@ struct ad7879 *ad7879_probe(struct device *dev, u8 devid, unsigned int irq,
__set_bit(EV_KEY, input_dev->evbit);
__set_bit(BTN_TOUCH, input_dev->keybit);
- input_set_abs_params(input_dev, ABS_X,
- pdata->x_min ? : 0,
- pdata->x_max ? : MAX_12BIT,
- 0, 0);
- input_set_abs_params(input_dev, ABS_Y,
- pdata->y_min ? : 0,
- pdata->y_max ? : MAX_12BIT,
- 0, 0);
- input_set_abs_params(input_dev, ABS_PRESSURE,
- pdata->pressure_min, pdata->pressure_max, 0, 0);
+ if (pdata) {
+ input_set_abs_params(input_dev, ABS_X,
+ pdata->x_min ? : 0,
+ pdata->x_max ? : MAX_12BIT,
+ 0, 0);
+ input_set_abs_params(input_dev, ABS_Y,
+ pdata->y_min ? : 0,
+ pdata->y_max ? : MAX_12BIT,
+ 0, 0);
+ input_set_abs_params(input_dev, ABS_PRESSURE,
+ pdata->pressure_min,
+ pdata->pressure_max ? : ~0,
+ 0, 0);
+ } else {
+ 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);
+ touchscreen_parse_properties(input_dev, false);
+ if (!input_abs_get_max(input_dev, ABS_PRESSURE)) {
+ dev_err(dev, "Touchscreen pressure is not specified\n");
+ return ERR_PTR(-EINVAL);
+ }
+ }
err = ad7879_write(ts, AD7879_REG_CTRL2, AD7879_RESET);
if (err < 0) {
dev_err(dev, "Failed to write %s\n", input_dev->name);
- goto err_free_mem;
+ return ERR_PTR(err);
}
revid = ad7879_read(ts, AD7879_REG_REVID);
@@ -575,8 +612,7 @@ struct ad7879 *ad7879_probe(struct device *dev, u8 devid, unsigned int irq,
if (input_dev->id.product != devid) {
dev_err(dev, "Failed to probe %s (%x vs %x)\n",
input_dev->name, devid, revid);
- err = -ENODEV;
- goto err_free_mem;
+ return ERR_PTR(-ENODEV);
}
ts->cmd_crtl3 = AD7879_YPLUS_BIT |
@@ -596,23 +632,25 @@ struct ad7879 *ad7879_probe(struct device *dev, u8 devid, unsigned int irq,
AD7879_ACQ(ts->acquisition_time) |
AD7879_TMR(ts->pen_down_acc_interval);
- err = request_threaded_irq(ts->irq, NULL, ad7879_irq,
- IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
- dev_name(dev), ts);
+ err = devm_request_threaded_irq(dev, ts->irq, NULL, ad7879_irq,
+ IRQF_TRIGGER_FALLING | IRQF_ONESHOT,
+ dev_name(dev), ts);
if (err) {
- dev_err(dev, "irq %d busy?\n", ts->irq);
- goto err_free_mem;
+ dev_err(dev, "Failed to request IRQ: %d\n", err);
+ return ERR_PTR(err);
}
__ad7879_disable(ts);
err = sysfs_create_group(&dev->kobj, &ad7879_attr_group);
if (err)
- goto err_free_irq;
+ goto err_out;
- err = ad7879_gpio_add(ts, pdata);
- if (err)
- goto err_remove_attr;
+ if (pdata) {
+ err = ad7879_gpio_add(ts, pdata);
+ if (err)
+ goto err_remove_attr;
+ }
err = input_register_device(input_dev);
if (err)
@@ -624,11 +662,6 @@ err_remove_gpio:
ad7879_gpio_remove(ts);
err_remove_attr:
sysfs_remove_group(&dev->kobj, &ad7879_attr_group);
-err_free_irq:
- free_irq(ts->irq, ts);
-err_free_mem:
- input_free_device(input_dev);
- kfree(ts);
err_out:
return ERR_PTR(err);
}
@@ -638,9 +671,7 @@ void ad7879_remove(struct ad7879 *ts)
{
ad7879_gpio_remove(ts);
sysfs_remove_group(&ts->dev->kobj, &ad7879_attr_group);
- free_irq(ts->irq, ts);
input_unregister_device(ts->input);
- kfree(ts);
}
EXPORT_SYMBOL(ad7879_remove);
