[PATCH v3 2/3] Input: cyttsp - add device tree bindings
From: Oreste Salerno
Date: Sun Jan 10 2016 - 12:37:11 EST
Signed-off-by: Oreste Salerno <oreste.salerno@xxxxxxxxxx>
---
.../bindings/input/touchscreen/cyttsp.txt | 82 +++++++++++++
drivers/input/touchscreen/cyttsp_core.c | 134 +++++++++++++++++++--
include/linux/input/cyttsp.h | 3 +
3 files changed, 212 insertions(+), 7 deletions(-)
create mode 100644 Documentation/devicetree/bindings/input/touchscreen/cyttsp.txt
diff --git a/Documentation/devicetree/bindings/input/touchscreen/cyttsp.txt b/Documentation/devicetree/bindings/input/touchscreen/cyttsp.txt
new file mode 100644
index 0000000..2dc5c65
--- /dev/null
+++ b/Documentation/devicetree/bindings/input/touchscreen/cyttsp.txt
@@ -0,0 +1,82 @@
+* Cypress cyttsp touchscreen controller
+
+Required properties:
+- compatible : must be "cypress,cyttsp-i2c" or "cypress,cyttsp-spi"
+- reg : Device I2C address or SPI chip select number
+- spi-max-frequency : Maximum SPI clocking speed of the device (for cyttsp-spi)
+- interrupt-parent : the phandle for the gpio controller
+ (see interrupt binding[0]).
+- interrupts : (gpio) interrupt to which the chip is connected
+ (see interrupt binding[0]).
+- reset-gpios : the reset gpio the chip is connected to
+ (see GPIO binding[1] for more details).
+- touchscreen-size-x : horizontal resolution of touchscreen (in pixels)
+- touchscreen-size-y : vertical resolution of touchscreen (in pixels)
+- bootloader-key : the 8-byte bootloader key that is required to switch
+ the chip from bootloader mode (default mode) to
+ application mode.
+ This property has to be specified as an array of 8
+ '/bits/ 8' values.
+
+Optional properties:
+- active-distance : the distance in pixels beyond which a touch must move
+ before movement is detected and reported by the device.
+ Valid values: 0-15.
+- active-interval-ms : the minimum period in ms between consecutive
+ scanning/processing cycles when the chip is in active mode.
+ Valid values: 0-255.
+- lowpower-interval-ms : the minimum period in ms between consecutive
+ scanning/processing cycles when the chip is in low-power mode.
+ Valid values: 0-2550
+- touch-timeout-ms : minimum time in ms spent in the active power state while no
+ touches are detected before entering low-power mode.
+ Valid values: 0-2550
+
+[0]: Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
+[1]: Documentation/devicetree/bindings/gpio/gpio.txt
+
+Example:
+ &i2c1 {
+ /* ... */
+ cyttsp@a {
+ compatible = "cypress,cyttsp-i2c";
+ reg = <0xa>;
+ interrupt-parent = <&msm_gpio>;
+ interrupts = <13 0x2008>;
+ reset-gpios = <&msm_gpio 12 0x00>;
+
+ touchscreen-size-x = <800>;
+ touchscreen-size-y = <480>;
+ bootloader-key = /bits/ 8 <0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x08>;
+
+ active-distance = <8>;
+ active-interval-ms = <0>;
+ lowpower-interval-ms = <200>;
+ touch-timeout-ms = <100>;
+ };
+
+ /* ... */
+ };
+
+ &mcspi1 {
+ /* ... */
+ cyttsp@0 {
+ compatible = "cypress,cyttsp-spi";
+ spi-max-frequency = <6000000>;
+ reg = <0>;
+ interrupt-parent = <&msm_gpio>;
+ interrupts = <13 0x2008>;
+ reset-gpios = <&msm_gpio 12 0x00>;
+
+ touchscreen-size-x = <800>;
+ touchscreen-size-y = <480>;
+ bootloader-key = /bits/ 8 <0x01 0x02 0x03 0x04 0x05 0x06 0x07 0x08>;
+
+ active-distance = <8>;
+ active-interval-ms = <0>;
+ lowpower-interval-ms = <200>;
+ touch-timeout-ms = <100>;
+ };
+
+ /* ... */
+ };
diff --git a/drivers/input/touchscreen/cyttsp_core.c b/drivers/input/touchscreen/cyttsp_core.c
index 5b74e8b..5dc6bf6 100644
--- a/drivers/input/touchscreen/cyttsp_core.c
+++ b/drivers/input/touchscreen/cyttsp_core.c
@@ -33,6 +33,8 @@
#include <linux/gpio.h>
#include <linux/interrupt.h>
#include <linux/slab.h>
+#include <linux/of.h>
+#include <linux/gpio/consumer.h>
#include "cyttsp_core.h"
@@ -57,6 +59,7 @@
#define CY_DELAY_DFLT 20 /* ms */
#define CY_DELAY_MAX 500
#define CY_ACT_DIST_DFLT 0xF8
+#define CY_ACT_DIST_MASK 0x0F
#define CY_HNDSHK_BIT 0x80
/* device mode bits */
#define CY_OPERATE_MODE 0x00
@@ -528,18 +531,136 @@ static void cyttsp_close(struct input_dev *dev)
cyttsp_disable(ts);
}
+#ifdef CONFIG_OF
+static const struct cyttsp_platform_data *cyttsp_parse_dt(struct device *dev)
+{
+ struct device_node *np = dev->of_node;
+ struct cyttsp_platform_data *pdata;
+ u32 dt_value;
+ int ret;
+ static const char err_msg[] =
+ "property not provided in the device tree";
+
+ if (!np)
+ return ERR_PTR(-ENOENT);
+
+ pdata = devm_kzalloc(dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return ERR_PTR(-ENOMEM);
+
+ pdata->bl_keys = devm_kzalloc(dev, CY_NUM_BL_KEYS, GFP_KERNEL);
+ if (!pdata->bl_keys)
+ return ERR_PTR(-ENOMEM);
+
+ /* Set some default values */
+ pdata->act_dist = CY_ACT_DIST_DFLT;
+ pdata->act_intrvl = CY_ACT_INTRVL_DFLT;
+ pdata->tch_tmout = CY_TCH_TMOUT_DFLT;
+ pdata->lp_intrvl = CY_LP_INTRVL_DFLT;
+ pdata->name = "cyttsp";
+
+ ret = of_property_read_u32(np, "touchscreen-size-x", &pdata->maxx);
+ if (ret) {
+ dev_err(dev, "touchscreen-size-x %s\n", err_msg);
+ return ERR_PTR(ret);
+ }
+
+ ret = of_property_read_u32(np, "touchscreen-size-y", &pdata->maxy);
+ if (ret) {
+ dev_err(dev, "touchscreen-size-y %s\n", err_msg);
+ return ERR_PTR(ret);
+ }
+
+ pdata->reset_gpio = devm_gpiod_get(dev, "reset", GPIOD_OUT_LOW);
+ if (IS_ERR(pdata->reset_gpio)) {
+ ret = PTR_ERR(pdata->reset_gpio);
+ dev_err(dev, "error acquiring reset gpio: %d\n", ret);
+ return ERR_PTR(ret);
+ }
+
+ ret = of_property_read_u8_array(np, "bootloader-key",
+ pdata->bl_keys, CY_NUM_BL_KEYS);
+ if (ret) {
+ dev_err(dev, "bootloader-key %s\n", err_msg);
+ return ERR_PTR(ret);
+ }
+
+ if (!of_property_read_u32(np, "active-distance", &dt_value)) {
+ if (dt_value > 15) {
+ dev_err(dev, "active-distance (%u) must be [0-15]\n",
+ dt_value);
+ return ERR_PTR(-EINVAL);
+ }
+ pdata->act_dist &= ~CY_ACT_DIST_MASK;
+ pdata->act_dist |= (u8)dt_value;
+ }
+
+ if (!of_property_read_u32(np, "active-interval-ms", &dt_value)) {
+ if (dt_value > 255) {
+ dev_err(dev, "active-interval-ms (%u) must be [0-255]\n",
+ dt_value);
+ return ERR_PTR(-EINVAL);
+ }
+ pdata->act_intrvl = (u8)dt_value;
+ }
+
+ if (!of_property_read_u32(np, "lowpower-interval-ms", &dt_value)) {
+ if (dt_value > 2550) {
+ dev_err(dev, "lowpower-interval-ms (%u) must be [0-2550]\n",
+ dt_value);
+ return ERR_PTR(-EINVAL);
+ }
+ /* Register value is expressed in 0.01s / bit */
+ pdata->lp_intrvl = (u8)(dt_value/10);
+ }
+
+ if (!of_property_read_u32(np, "touch-timeout-ms", &dt_value)) {
+ if (dt_value > 2550) {
+ dev_err(dev, "touch-timeout-ms (%u) must be [0-2550]\n",
+ dt_value);
+ return ERR_PTR(-EINVAL);
+ }
+ /* Register value is expressed in 0.01s / bit */
+ pdata->tch_tmout = (u8)(dt_value/10);
+ }
+
+ return pdata;
+}
+#else
+static const struct cyttsp_platform_data *cyttsp_parse_dt(struct device *dev)
+{
+ return ERR_PTR(-ENOENT);
+}
+#endif
+
+static const struct cyttsp_platform_data *
+cyttsp_get_platform_data(struct device *dev)
+{
+ const struct cyttsp_platform_data *pdata;
+
+ pdata = dev_get_platdata(dev);
+ if (pdata)
+ return pdata;
+
+ pdata = cyttsp_parse_dt(dev);
+ if (!IS_ERR(pdata) || PTR_ERR(pdata) != -ENOENT)
+ return pdata;
+
+ dev_err(dev, "No platform data specified\n");
+ return ERR_PTR(-EINVAL);
+}
+
struct cyttsp *cyttsp_probe(const struct cyttsp_bus_ops *bus_ops,
struct device *dev, int irq, size_t xfer_buf_size)
{
- const struct cyttsp_platform_data *pdata = dev_get_platdata(dev);
+ const struct cyttsp_platform_data *pdata;
struct cyttsp *ts;
struct input_dev *input_dev;
int error;
- if (!pdata || !pdata->name || irq <= 0) {
- error = -EINVAL;
- goto err_out;
- }
+ pdata = cyttsp_get_platform_data(dev);
+ if (IS_ERR(pdata))
+ return ERR_CAST(pdata);
ts = kzalloc(sizeof(*ts) + xfer_buf_size, GFP_KERNEL);
input_dev = input_allocate_device();
@@ -550,7 +671,7 @@ struct cyttsp *cyttsp_probe(const struct cyttsp_bus_ops *bus_ops,
ts->dev = dev;
ts->input = input_dev;
- ts->pdata = dev_get_platdata(dev);
+ ts->pdata = pdata;
ts->bus_ops = bus_ops;
ts->irq = irq;
@@ -618,7 +739,6 @@ err_platform_exit:
err_free_mem:
input_free_device(input_dev);
kfree(ts);
-err_out:
return ERR_PTR(error);
}
EXPORT_SYMBOL_GPL(cyttsp_probe);
diff --git a/include/linux/input/cyttsp.h b/include/linux/input/cyttsp.h
index d7c2520..92a9d52 100644
--- a/include/linux/input/cyttsp.h
+++ b/include/linux/input/cyttsp.h
@@ -29,6 +29,8 @@
#ifndef _CYTTSP_H_
#define _CYTTSP_H_
+#include <linux/gpio/consumer.h>
+
#define CY_SPI_NAME "cyttsp-spi"
#define CY_I2C_NAME "cyttsp-i2c"
/* Active Power state scanning/processing refresh interval */
@@ -51,6 +53,7 @@ struct cyttsp_platform_data {
int (*init)(void);
void (*exit)(void);
char *name;
+ struct gpio_desc *reset_gpio;
u8 *bl_keys;
};
--
1.9.1