linux/drivers/input/touchscreen/surface3_spi.c
Colin Ian King 023c437a7a Input: surface3_spi - make const array header static, reduces object code size
Don't populate the const array header on the stack, instead make it
static.  Makes the object code smaller by over 180 bytes:

Before:
   text	   data	    bss	    dec	    hex	filename
   6003	   1536	      0	   7539	   1d73	surface3_spi.o

After:
   text	   data	    bss	    dec	    hex	filename
   5726	   1632	      0	   7358	   1cbe	surface3_spi.o

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
2017-09-11 14:23:39 -07:00

428 lines
9.9 KiB
C

/*
* Driver for Ntrig/Microsoft Touchscreens over SPI
*
* Copyright (c) 2016 Red Hat Inc.
*/
/*
* 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 of the License.
*/
#include <linux/kernel.h>
#include <linux/delay.h>
#include <linux/gpio/consumer.h>
#include <linux/input.h>
#include <linux/input/mt.h>
#include <linux/interrupt.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/spi/spi.h>
#include <linux/acpi.h>
#include <asm/unaligned.h>
#define SURFACE3_PACKET_SIZE 264
#define SURFACE3_REPORT_TOUCH 0xd2
#define SURFACE3_REPORT_PEN 0x16
struct surface3_ts_data {
struct spi_device *spi;
struct gpio_desc *gpiod_rst[2];
struct input_dev *input_dev;
struct input_dev *pen_input_dev;
int pen_tool;
u8 rd_buf[SURFACE3_PACKET_SIZE] ____cacheline_aligned;
};
struct surface3_ts_data_finger {
u8 status;
__le16 tracking_id;
__le16 x;
__le16 cx;
__le16 y;
__le16 cy;
__le16 width;
__le16 height;
u32 padding;
} __packed;
struct surface3_ts_data_pen {
u8 status;
__le16 x;
__le16 y;
__le16 pressure;
u8 padding;
} __packed;
static int surface3_spi_read(struct surface3_ts_data *ts_data)
{
struct spi_device *spi = ts_data->spi;
memset(ts_data->rd_buf, 0, sizeof(ts_data->rd_buf));
return spi_read(spi, ts_data->rd_buf, sizeof(ts_data->rd_buf));
}
static void surface3_spi_report_touch(struct surface3_ts_data *ts_data,
struct surface3_ts_data_finger *finger)
{
int st = finger->status & 0x01;
int slot;
slot = input_mt_get_slot_by_key(ts_data->input_dev,
get_unaligned_le16(&finger->tracking_id));
if (slot < 0)
return;
input_mt_slot(ts_data->input_dev, slot);
input_mt_report_slot_state(ts_data->input_dev, MT_TOOL_FINGER, st);
if (st) {
input_report_abs(ts_data->input_dev,
ABS_MT_POSITION_X,
get_unaligned_le16(&finger->x));
input_report_abs(ts_data->input_dev,
ABS_MT_POSITION_Y,
get_unaligned_le16(&finger->y));
input_report_abs(ts_data->input_dev,
ABS_MT_WIDTH_MAJOR,
get_unaligned_le16(&finger->width));
input_report_abs(ts_data->input_dev,
ABS_MT_WIDTH_MINOR,
get_unaligned_le16(&finger->height));
}
}
static void surface3_spi_process_touch(struct surface3_ts_data *ts_data, u8 *data)
{
u16 timestamp;
unsigned int i;
timestamp = get_unaligned_le16(&data[15]);
for (i = 0; i < 13; i++) {
struct surface3_ts_data_finger *finger;
finger = (struct surface3_ts_data_finger *)&data[17 +
i * sizeof(struct surface3_ts_data_finger)];
/*
* When bit 5 of status is 1, it marks the end of the report:
* - touch present: 0xe7
* - touch released: 0xe4
* - nothing valuable: 0xff
*/
if (finger->status & 0x10)
break;
surface3_spi_report_touch(ts_data, finger);
}
input_mt_sync_frame(ts_data->input_dev);
input_sync(ts_data->input_dev);
}
static void surface3_spi_report_pen(struct surface3_ts_data *ts_data,
struct surface3_ts_data_pen *pen)
{
struct input_dev *dev = ts_data->pen_input_dev;
int st = pen->status;
int prox = st & 0x01;
int rubber = st & 0x18;
int tool = (prox && rubber) ? BTN_TOOL_RUBBER : BTN_TOOL_PEN;
/* fake proximity out to switch tools */
if (ts_data->pen_tool != tool) {
input_report_key(dev, ts_data->pen_tool, 0);
input_sync(dev);
ts_data->pen_tool = tool;
}
input_report_key(dev, BTN_TOUCH, st & 0x12);
input_report_key(dev, ts_data->pen_tool, prox);
if (st) {
input_report_key(dev,
BTN_STYLUS,
st & 0x04);
input_report_abs(dev,
ABS_X,
get_unaligned_le16(&pen->x));
input_report_abs(dev,
ABS_Y,
get_unaligned_le16(&pen->y));
input_report_abs(dev,
ABS_PRESSURE,
get_unaligned_le16(&pen->pressure));
}
}
static void surface3_spi_process_pen(struct surface3_ts_data *ts_data, u8 *data)
{
struct surface3_ts_data_pen *pen;
pen = (struct surface3_ts_data_pen *)&data[15];
surface3_spi_report_pen(ts_data, pen);
input_sync(ts_data->pen_input_dev);
}
static void surface3_spi_process(struct surface3_ts_data *ts_data)
{
static const char header[] = {
0xff, 0xff, 0xff, 0xff, 0xa5, 0x5a, 0xe7, 0x7e, 0x01
};
u8 *data = ts_data->rd_buf;
if (memcmp(header, data, sizeof(header)))
dev_err(&ts_data->spi->dev,
"%s header error: %*ph, ignoring...\n",
__func__, (int)sizeof(header), data);
switch (data[9]) {
case SURFACE3_REPORT_TOUCH:
surface3_spi_process_touch(ts_data, data);
break;
case SURFACE3_REPORT_PEN:
surface3_spi_process_pen(ts_data, data);
break;
default:
dev_err(&ts_data->spi->dev,
"%s unknown packet type: %x, ignoring...\n",
__func__, data[9]);
break;
}
}
static irqreturn_t surface3_spi_irq_handler(int irq, void *dev_id)
{
struct surface3_ts_data *data = dev_id;
if (surface3_spi_read(data))
return IRQ_HANDLED;
dev_dbg(&data->spi->dev, "%s received -> %*ph\n",
__func__, SURFACE3_PACKET_SIZE, data->rd_buf);
surface3_spi_process(data);
return IRQ_HANDLED;
}
static void surface3_spi_power(struct surface3_ts_data *data, bool on)
{
gpiod_set_value(data->gpiod_rst[0], on);
gpiod_set_value(data->gpiod_rst[1], on);
/* let the device settle a little */
msleep(20);
}
/**
* surface3_spi_get_gpio_config - Get GPIO config from ACPI/DT
*
* @ts: surface3_spi_ts_data pointer
*/
static int surface3_spi_get_gpio_config(struct surface3_ts_data *data)
{
int error;
struct device *dev;
struct gpio_desc *gpiod;
int i;
dev = &data->spi->dev;
/* Get the reset lines GPIO pin number */
for (i = 0; i < 2; i++) {
gpiod = devm_gpiod_get_index(dev, NULL, i, GPIOD_OUT_LOW);
if (IS_ERR(gpiod)) {
error = PTR_ERR(gpiod);
if (error != -EPROBE_DEFER)
dev_err(dev,
"Failed to get power GPIO %d: %d\n",
i,
error);
return error;
}
data->gpiod_rst[i] = gpiod;
}
return 0;
}
static int surface3_spi_create_touch_input(struct surface3_ts_data *data)
{
struct input_dev *input;
int error;
input = devm_input_allocate_device(&data->spi->dev);
if (!input)
return -ENOMEM;
data->input_dev = input;
input_set_abs_params(input, ABS_MT_POSITION_X, 0, 9600, 0, 0);
input_abs_set_res(input, ABS_MT_POSITION_X, 40);
input_set_abs_params(input, ABS_MT_POSITION_Y, 0, 7200, 0, 0);
input_abs_set_res(input, ABS_MT_POSITION_Y, 48);
input_set_abs_params(input, ABS_MT_WIDTH_MAJOR, 0, 1024, 0, 0);
input_set_abs_params(input, ABS_MT_WIDTH_MINOR, 0, 1024, 0, 0);
input_mt_init_slots(input, 10, INPUT_MT_DIRECT);
input->name = "Surface3 SPI Capacitive TouchScreen";
input->phys = "input/ts";
input->id.bustype = BUS_SPI;
input->id.vendor = 0x045e; /* Microsoft */
input->id.product = 0x0001;
input->id.version = 0x0000;
error = input_register_device(input);
if (error) {
dev_err(&data->spi->dev,
"Failed to register input device: %d", error);
return error;
}
return 0;
}
static int surface3_spi_create_pen_input(struct surface3_ts_data *data)
{
struct input_dev *input;
int error;
input = devm_input_allocate_device(&data->spi->dev);
if (!input)
return -ENOMEM;
data->pen_input_dev = input;
data->pen_tool = BTN_TOOL_PEN;
__set_bit(INPUT_PROP_DIRECT, input->propbit);
__set_bit(INPUT_PROP_POINTER, input->propbit);
input_set_abs_params(input, ABS_X, 0, 9600, 0, 0);
input_abs_set_res(input, ABS_X, 40);
input_set_abs_params(input, ABS_Y, 0, 7200, 0, 0);
input_abs_set_res(input, ABS_Y, 48);
input_set_abs_params(input, ABS_PRESSURE, 0, 1024, 0, 0);
input_set_capability(input, EV_KEY, BTN_TOUCH);
input_set_capability(input, EV_KEY, BTN_STYLUS);
input_set_capability(input, EV_KEY, BTN_TOOL_PEN);
input_set_capability(input, EV_KEY, BTN_TOOL_RUBBER);
input->name = "Surface3 SPI Pen Input";
input->phys = "input/ts";
input->id.bustype = BUS_SPI;
input->id.vendor = 0x045e; /* Microsoft */
input->id.product = 0x0002;
input->id.version = 0x0000;
error = input_register_device(input);
if (error) {
dev_err(&data->spi->dev,
"Failed to register input device: %d", error);
return error;
}
return 0;
}
static int surface3_spi_probe(struct spi_device *spi)
{
struct surface3_ts_data *data;
int error;
/* Set up SPI*/
spi->bits_per_word = 8;
spi->mode = SPI_MODE_0;
error = spi_setup(spi);
if (error)
return error;
data = devm_kzalloc(&spi->dev, sizeof(*data), GFP_KERNEL);
if (!data)
return -ENOMEM;
data->spi = spi;
spi_set_drvdata(spi, data);
error = surface3_spi_get_gpio_config(data);
if (error)
return error;
surface3_spi_power(data, true);
surface3_spi_power(data, false);
surface3_spi_power(data, true);
error = surface3_spi_create_touch_input(data);
if (error)
return error;
error = surface3_spi_create_pen_input(data);
if (error)
return error;
error = devm_request_threaded_irq(&spi->dev, spi->irq,
NULL, surface3_spi_irq_handler,
IRQF_ONESHOT,
"Surface3-irq", data);
if (error)
return error;
return 0;
}
static int __maybe_unused surface3_spi_suspend(struct device *dev)
{
struct spi_device *spi = to_spi_device(dev);
struct surface3_ts_data *data = spi_get_drvdata(spi);
disable_irq(data->spi->irq);
surface3_spi_power(data, false);
return 0;
}
static int __maybe_unused surface3_spi_resume(struct device *dev)
{
struct spi_device *spi = to_spi_device(dev);
struct surface3_ts_data *data = spi_get_drvdata(spi);
surface3_spi_power(data, true);
enable_irq(data->spi->irq);
return 0;
}
static SIMPLE_DEV_PM_OPS(surface3_spi_pm_ops,
surface3_spi_suspend,
surface3_spi_resume);
#ifdef CONFIG_ACPI
static const struct acpi_device_id surface3_spi_acpi_match[] = {
{ "MSHW0037", 0 },
{ }
};
MODULE_DEVICE_TABLE(acpi, surface3_spi_acpi_match);
#endif
static struct spi_driver surface3_spi_driver = {
.driver = {
.name = "Surface3-spi",
.acpi_match_table = ACPI_PTR(surface3_spi_acpi_match),
.pm = &surface3_spi_pm_ops,
},
.probe = surface3_spi_probe,
};
module_spi_driver(surface3_spi_driver);
MODULE_AUTHOR("Benjamin Tissoires <benjamin.tissoires@gmail.com>");
MODULE_DESCRIPTION("Surface 3 SPI touchscreen driver");
MODULE_LICENSE("GPL v2");