linux/drivers/hid/hid-elan.c
Hans de Goede ba3f92938f HID: elan: Remove elan_mute_led_get_brigtness()
The led_classdev already contains a cached value of the last set
brightness, the brightness_get callback is only meant for LED drivers
which can read back the actual / current brightness from the hardware.

Since elan_mute_led_get_brigtness() just returns the last set value
it does not add any functionality, so we can just remove it.

Reviewed-by: Marek Behún <kabel@kernel.org>
Acked-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2021-04-07 12:46:33 +02:00

542 lines
13 KiB
C

// SPDX-License-Identifier: GPL-2.0-or-later
/*
* HID Driver for ELAN Touchpad
*
* Currently only supports touchpad found on HP Pavilion X2 10
*
* Copyright (c) 2016 Alexandrov Stanislav <neko@nya.ai>
*/
#include <linux/hid.h>
#include <linux/input/mt.h>
#include <linux/leds.h>
#include <linux/module.h>
#include <linux/usb.h>
#include "hid-ids.h"
#define ELAN_MT_I2C 0x5d
#define ELAN_SINGLE_FINGER 0x81
#define ELAN_MT_FIRST_FINGER 0x82
#define ELAN_MT_SECOND_FINGER 0x83
#define ELAN_INPUT_REPORT_SIZE 8
#define ELAN_I2C_REPORT_SIZE 32
#define ELAN_FINGER_DATA_LEN 5
#define ELAN_MAX_FINGERS 5
#define ELAN_MAX_PRESSURE 255
#define ELAN_TP_USB_INTF 1
#define ELAN_FEATURE_REPORT 0x0d
#define ELAN_FEATURE_SIZE 5
#define ELAN_PARAM_MAX_X 6
#define ELAN_PARAM_MAX_Y 7
#define ELAN_PARAM_RES 8
#define ELAN_MUTE_LED_REPORT 0xBC
#define ELAN_LED_REPORT_SIZE 8
#define ELAN_HAS_LED BIT(0)
struct elan_drvdata {
struct input_dev *input;
u8 prev_report[ELAN_INPUT_REPORT_SIZE];
struct led_classdev mute_led;
u8 mute_led_state;
u16 max_x;
u16 max_y;
u16 res_x;
u16 res_y;
};
static int is_not_elan_touchpad(struct hid_device *hdev)
{
if (hdev->bus == BUS_USB) {
struct usb_interface *intf = to_usb_interface(hdev->dev.parent);
return (intf->altsetting->desc.bInterfaceNumber !=
ELAN_TP_USB_INTF);
}
return 0;
}
static int elan_input_mapping(struct hid_device *hdev, struct hid_input *hi,
struct hid_field *field, struct hid_usage *usage,
unsigned long **bit, int *max)
{
if (is_not_elan_touchpad(hdev))
return 0;
if (field->report->id == ELAN_SINGLE_FINGER ||
field->report->id == ELAN_MT_FIRST_FINGER ||
field->report->id == ELAN_MT_SECOND_FINGER ||
field->report->id == ELAN_MT_I2C)
return -1;
return 0;
}
static int elan_get_device_param(struct hid_device *hdev,
unsigned char *dmabuf, unsigned char param)
{
int ret;
dmabuf[0] = ELAN_FEATURE_REPORT;
dmabuf[1] = 0x05;
dmabuf[2] = 0x03;
dmabuf[3] = param;
dmabuf[4] = 0x01;
ret = hid_hw_raw_request(hdev, ELAN_FEATURE_REPORT, dmabuf,
ELAN_FEATURE_SIZE, HID_FEATURE_REPORT,
HID_REQ_SET_REPORT);
if (ret != ELAN_FEATURE_SIZE) {
hid_err(hdev, "Set report error for parm %d: %d\n", param, ret);
return ret;
}
ret = hid_hw_raw_request(hdev, ELAN_FEATURE_REPORT, dmabuf,
ELAN_FEATURE_SIZE, HID_FEATURE_REPORT,
HID_REQ_GET_REPORT);
if (ret != ELAN_FEATURE_SIZE) {
hid_err(hdev, "Get report error for parm %d: %d\n", param, ret);
return ret;
}
return 0;
}
static unsigned int elan_convert_res(char val)
{
/*
* (value from firmware) * 10 + 790 = dpi
* dpi * 10 / 254 = dots/mm
*/
return (val * 10 + 790) * 10 / 254;
}
static int elan_get_device_params(struct hid_device *hdev)
{
struct elan_drvdata *drvdata = hid_get_drvdata(hdev);
unsigned char *dmabuf;
int ret;
dmabuf = kmalloc(ELAN_FEATURE_SIZE, GFP_KERNEL);
if (!dmabuf)
return -ENOMEM;
ret = elan_get_device_param(hdev, dmabuf, ELAN_PARAM_MAX_X);
if (ret)
goto err;
drvdata->max_x = (dmabuf[4] << 8) | dmabuf[3];
ret = elan_get_device_param(hdev, dmabuf, ELAN_PARAM_MAX_Y);
if (ret)
goto err;
drvdata->max_y = (dmabuf[4] << 8) | dmabuf[3];
ret = elan_get_device_param(hdev, dmabuf, ELAN_PARAM_RES);
if (ret)
goto err;
drvdata->res_x = elan_convert_res(dmabuf[3]);
drvdata->res_y = elan_convert_res(dmabuf[4]);
err:
kfree(dmabuf);
return ret;
}
static int elan_input_configured(struct hid_device *hdev, struct hid_input *hi)
{
int ret;
struct input_dev *input;
struct elan_drvdata *drvdata = hid_get_drvdata(hdev);
if (is_not_elan_touchpad(hdev))
return 0;
ret = elan_get_device_params(hdev);
if (ret)
return ret;
input = devm_input_allocate_device(&hdev->dev);
if (!input)
return -ENOMEM;
input->name = "Elan Touchpad";
input->phys = hdev->phys;
input->uniq = hdev->uniq;
input->id.bustype = hdev->bus;
input->id.vendor = hdev->vendor;
input->id.product = hdev->product;
input->id.version = hdev->version;
input->dev.parent = &hdev->dev;
input_set_abs_params(input, ABS_MT_POSITION_X, 0, drvdata->max_x,
0, 0);
input_set_abs_params(input, ABS_MT_POSITION_Y, 0, drvdata->max_y,
0, 0);
input_set_abs_params(input, ABS_MT_PRESSURE, 0, ELAN_MAX_PRESSURE,
0, 0);
__set_bit(BTN_LEFT, input->keybit);
__set_bit(INPUT_PROP_BUTTONPAD, input->propbit);
ret = input_mt_init_slots(input, ELAN_MAX_FINGERS, INPUT_MT_POINTER);
if (ret) {
hid_err(hdev, "Failed to init elan MT slots: %d\n", ret);
input_free_device(input);
return ret;
}
input_abs_set_res(input, ABS_X, drvdata->res_x);
input_abs_set_res(input, ABS_Y, drvdata->res_y);
ret = input_register_device(input);
if (ret) {
hid_err(hdev, "Failed to register elan input device: %d\n",
ret);
input_mt_destroy_slots(input);
input_free_device(input);
return ret;
}
drvdata->input = input;
return 0;
}
static void elan_report_mt_slot(struct elan_drvdata *drvdata, u8 *data,
unsigned int slot_num)
{
struct input_dev *input = drvdata->input;
int x, y, p;
bool active = !!data;
input_mt_slot(input, slot_num);
input_mt_report_slot_state(input, MT_TOOL_FINGER, active);
if (active) {
x = ((data[0] & 0xF0) << 4) | data[1];
y = drvdata->max_y -
(((data[0] & 0x07) << 8) | data[2]);
p = data[4];
input_report_abs(input, ABS_MT_POSITION_X, x);
input_report_abs(input, ABS_MT_POSITION_Y, y);
input_report_abs(input, ABS_MT_PRESSURE, p);
}
}
static void elan_usb_report_input(struct elan_drvdata *drvdata, u8 *data)
{
int i;
struct input_dev *input = drvdata->input;
/*
* There is 3 types of reports: for single touch,
* for multitouch - first finger and for multitouch - second finger
*
* packet structure for ELAN_SINGLE_FINGER and ELAN_MT_FIRST_FINGER:
*
* byte 1: 1 0 0 0 0 0 0 1 // 0x81 or 0x82
* byte 2: 0 0 0 0 0 0 0 0 // looks like unused
* byte 3: f5 f4 f3 f2 f1 0 0 L
* byte 4: x12 x11 x10 x9 0? y11 y10 y9
* byte 5: x8 x7 x6 x5 x4 x3 x2 x1
* byte 6: y8 y7 y6 y5 y4 y3 y2 y1
* byte 7: sy4 sy3 sy2 sy1 sx4 sx3 sx2 sx1
* byte 8: p8 p7 p6 p5 p4 p3 p2 p1
*
* packet structure for ELAN_MT_SECOND_FINGER:
*
* byte 1: 1 0 0 0 0 0 1 1 // 0x83
* byte 2: x12 x11 x10 x9 0 y11 y10 y9
* byte 3: x8 x7 x6 x5 x4 x3 x2 x1
* byte 4: y8 y7 y6 y5 y4 y3 y2 y1
* byte 5: sy4 sy3 sy2 sy1 sx4 sx3 sx2 sx1
* byte 6: p8 p7 p6 p5 p4 p3 p2 p1
* byte 7: 0 0 0 0 0 0 0 0
* byte 8: 0 0 0 0 0 0 0 0
*
* f5-f1: finger touch bits
* L: clickpad button
* sy / sx: finger width / height expressed in traces, the total number
* of traces can be queried by doing a HID_REQ_SET_REPORT
* { 0x0d, 0x05, 0x03, 0x05, 0x01 } followed by a GET, in the
* returned buf, buf[3]=no-x-traces, buf[4]=no-y-traces.
* p: pressure
*/
if (data[0] == ELAN_SINGLE_FINGER) {
for (i = 0; i < ELAN_MAX_FINGERS; i++) {
if (data[2] & BIT(i + 3))
elan_report_mt_slot(drvdata, data + 3, i);
else
elan_report_mt_slot(drvdata, NULL, i);
}
input_report_key(input, BTN_LEFT, data[2] & 0x01);
}
/*
* When touched with two fingers Elan touchpad will emit two HID reports
* first is ELAN_MT_FIRST_FINGER and second is ELAN_MT_SECOND_FINGER
* we will save ELAN_MT_FIRST_FINGER report and wait for
* ELAN_MT_SECOND_FINGER to finish multitouch
*/
if (data[0] == ELAN_MT_FIRST_FINGER) {
memcpy(drvdata->prev_report, data,
sizeof(drvdata->prev_report));
return;
}
if (data[0] == ELAN_MT_SECOND_FINGER) {
int first = 0;
u8 *prev_report = drvdata->prev_report;
if (prev_report[0] != ELAN_MT_FIRST_FINGER)
return;
for (i = 0; i < ELAN_MAX_FINGERS; i++) {
if (prev_report[2] & BIT(i + 3)) {
if (!first) {
first = 1;
elan_report_mt_slot(drvdata, prev_report + 3, i);
} else {
elan_report_mt_slot(drvdata, data + 1, i);
}
} else {
elan_report_mt_slot(drvdata, NULL, i);
}
}
input_report_key(input, BTN_LEFT, prev_report[2] & 0x01);
}
input_mt_sync_frame(input);
input_sync(input);
}
static void elan_i2c_report_input(struct elan_drvdata *drvdata, u8 *data)
{
struct input_dev *input = drvdata->input;
u8 *finger_data;
int i;
/*
* Elan MT touchpads in i2c mode send finger data in the same format
* as in USB mode, but then with all fingers in a single packet.
*
* packet structure for ELAN_MT_I2C:
*
* byte 1: 1 0 0 1 1 1 0 1 // 0x5d
* byte 2: f5 f4 f3 f2 f1 0 0 L
* byte 3: x12 x11 x10 x9 0? y11 y10 y9
* byte 4: x8 x7 x6 x5 x4 x3 x2 x1
* byte 5: y8 y7 y6 y5 y4 y3 y2 y1
* byte 6: sy4 sy3 sy2 sy1 sx4 sx3 sx2 sx1
* byte 7: p8 p7 p6 p5 p4 p3 p2 p1
* byte 8-12: Same as byte 3-7 for second finger down
* byte 13-17: Same as byte 3-7 for third finger down
* byte 18-22: Same as byte 3-7 for fourth finger down
* byte 23-27: Same as byte 3-7 for fifth finger down
*/
finger_data = data + 2;
for (i = 0; i < ELAN_MAX_FINGERS; i++) {
if (data[1] & BIT(i + 3)) {
elan_report_mt_slot(drvdata, finger_data, i);
finger_data += ELAN_FINGER_DATA_LEN;
} else {
elan_report_mt_slot(drvdata, NULL, i);
}
}
input_report_key(input, BTN_LEFT, data[1] & 0x01);
input_mt_sync_frame(input);
input_sync(input);
}
static int elan_raw_event(struct hid_device *hdev,
struct hid_report *report, u8 *data, int size)
{
struct elan_drvdata *drvdata = hid_get_drvdata(hdev);
if (is_not_elan_touchpad(hdev))
return 0;
if (data[0] == ELAN_SINGLE_FINGER ||
data[0] == ELAN_MT_FIRST_FINGER ||
data[0] == ELAN_MT_SECOND_FINGER) {
if (size == ELAN_INPUT_REPORT_SIZE) {
elan_usb_report_input(drvdata, data);
return 1;
}
}
if (data[0] == ELAN_MT_I2C && size == ELAN_I2C_REPORT_SIZE) {
elan_i2c_report_input(drvdata, data);
return 1;
}
return 0;
}
static int elan_start_multitouch(struct hid_device *hdev)
{
int ret;
/*
* This byte sequence will enable multitouch mode and disable
* mouse emulation
*/
static const unsigned char buf[] = { 0x0D, 0x00, 0x03, 0x21, 0x00 };
unsigned char *dmabuf = kmemdup(buf, sizeof(buf), GFP_KERNEL);
if (!dmabuf)
return -ENOMEM;
ret = hid_hw_raw_request(hdev, dmabuf[0], dmabuf, sizeof(buf),
HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
kfree(dmabuf);
if (ret != sizeof(buf)) {
hid_err(hdev, "Failed to start multitouch: %d\n", ret);
return ret;
}
return 0;
}
static int elan_mute_led_set_brigtness(struct led_classdev *led_cdev,
enum led_brightness value)
{
int ret;
u8 led_state;
struct device *dev = led_cdev->dev->parent;
struct hid_device *hdev = to_hid_device(dev);
struct elan_drvdata *drvdata = hid_get_drvdata(hdev);
unsigned char *dmabuf = kzalloc(ELAN_LED_REPORT_SIZE, GFP_KERNEL);
if (!dmabuf)
return -ENOMEM;
led_state = !!value;
dmabuf[0] = ELAN_MUTE_LED_REPORT;
dmabuf[1] = 0x02;
dmabuf[2] = led_state;
ret = hid_hw_raw_request(hdev, dmabuf[0], dmabuf, ELAN_LED_REPORT_SIZE,
HID_FEATURE_REPORT, HID_REQ_SET_REPORT);
kfree(dmabuf);
if (ret != ELAN_LED_REPORT_SIZE) {
if (ret != -ENODEV)
hid_err(hdev, "Failed to set mute led brightness: %d\n", ret);
return ret < 0 ? ret : -EIO;
}
drvdata->mute_led_state = led_state;
return 0;
}
static int elan_init_mute_led(struct hid_device *hdev)
{
struct elan_drvdata *drvdata = hid_get_drvdata(hdev);
struct led_classdev *mute_led = &drvdata->mute_led;
mute_led->name = "elan:red:mute";
mute_led->default_trigger = "audio-mute";
mute_led->brightness_set_blocking = elan_mute_led_set_brigtness;
mute_led->max_brightness = LED_ON;
mute_led->flags = LED_HW_PLUGGABLE;
mute_led->dev = &hdev->dev;
return devm_led_classdev_register(&hdev->dev, mute_led);
}
static int elan_probe(struct hid_device *hdev, const struct hid_device_id *id)
{
int ret;
struct elan_drvdata *drvdata;
drvdata = devm_kzalloc(&hdev->dev, sizeof(*drvdata), GFP_KERNEL);
if (!drvdata)
return -ENOMEM;
hid_set_drvdata(hdev, drvdata);
ret = hid_parse(hdev);
if (ret) {
hid_err(hdev, "Hid Parse failed\n");
return ret;
}
ret = hid_hw_start(hdev, HID_CONNECT_DEFAULT);
if (ret) {
hid_err(hdev, "Hid hw start failed\n");
return ret;
}
if (is_not_elan_touchpad(hdev))
return 0;
if (!drvdata->input) {
hid_err(hdev, "Input device is not registered\n");
ret = -ENAVAIL;
goto err;
}
ret = elan_start_multitouch(hdev);
if (ret)
goto err;
if (id->driver_data & ELAN_HAS_LED) {
ret = elan_init_mute_led(hdev);
if (ret)
goto err;
}
return 0;
err:
hid_hw_stop(hdev);
return ret;
}
static void elan_remove(struct hid_device *hdev)
{
hid_hw_stop(hdev);
}
static const struct hid_device_id elan_devices[] = {
{ HID_USB_DEVICE(USB_VENDOR_ID_ELAN, USB_DEVICE_ID_HP_X2),
.driver_data = ELAN_HAS_LED },
{ HID_USB_DEVICE(USB_VENDOR_ID_ELAN, USB_DEVICE_ID_HP_X2_10_COVER),
.driver_data = ELAN_HAS_LED },
{ HID_I2C_DEVICE(USB_VENDOR_ID_ELAN, USB_DEVICE_ID_TOSHIBA_CLICK_L9W) },
{ }
};
MODULE_DEVICE_TABLE(hid, elan_devices);
static struct hid_driver elan_driver = {
.name = "elan",
.id_table = elan_devices,
.input_mapping = elan_input_mapping,
.input_configured = elan_input_configured,
.raw_event = elan_raw_event,
.probe = elan_probe,
.remove = elan_remove,
};
module_hid_driver(elan_driver);
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Alexandrov Stanislav");
MODULE_DESCRIPTION("Driver for HID ELAN Touchpads");