哇酷®开发者社区(WhyCan® Forum)

/*

• WHYCAN (哇酷®) Copyright (C)
  */

#include <linux/err.h>
#include <linux/hwmon.h>
#include <linux/thermal.h>
#include <linux/init.h>
#include <linux/input.h>
#include <linux/interrupt.h>
#include <linux/io.h>
#include <linux/module.h>
#include <linux/of_platform.h>
#include <linux/platform_device.h>
#include <linux/slab.h>

#define TP_CTRL0 0x00
#define TP_CTRL1 0x04
#define TP_CTRL2 0x08
#define TP_CTRL3 0x0c
#define TP_INT_FIFOC 0x10
#define TP_INT_FIFOS 0x14
#define TP_TPR 0x18
#define TP_CDAT 0x1c
#define TEMP_DATA 0x20
#define TP_DATA 0x24

/ TP_CTRL0 bits /
#define ADC_FIRST_DLY(x) ((x) << 24) / 8 bits /
#define ADC_FIRST_DLY_MODE(x) ((x) << 23)
#define ADC_CLK_SEL(x) ((x) << 22)
#define ADC_CLK_DIV(x) ((x) << 20) / 3 bits /
#define FS_DIV(x) ((x) << 16) / 4 bits /
#define T_ACQ(x) ((x) << 0) / 16 bits /

/ TP_CTRL1 bits /
#define STYLUS_UP_DEBOUN(x) ((x) << 12) / 8 bits /
#define STYLUS_UP_DEBOUN_EN(x) ((x) << 9)
#define TOUCH_PAN_CALI_EN(x) ((x) << 6)
#define TP_DUAL_EN(x) ((x) << 5)
#define TP_MODE_EN(x) ((x) << 4)
#define TP_ADC_SELECT(x) ((x) << 3)
#define ADC_CHAN_SELECT(x) ((x) << 0) / 3 bits /

/ on sun6i, bits 3~6 are left shifted by 1 to 4~7 /
#define SUN6I_TP_MODE_EN(x) ((x) << 5)

/ TP_CTRL2 bits /
#define TP_SENSITIVE_ADJUST(x) ((x) << 28) / 4 bits /
#define TP_MODE_SELECT(x) ((x) << 26) / 2 bits /
#define PRE_MEA_EN(x) ((x) << 24)
#define PRE_MEA_THRE_CNT(x) ((x) << 0) / 24 bits /

/ TP_CTRL3 bits /
#define FILTER_EN(x) ((x) << 2)
#define FILTER_TYPE(x) ((x) << 0) / 2 bits /

/ TP_INT_FIFOC irq and fifo mask / control bits /
#define TEMP_IRQ_EN(x) ((x) << 18)
#define OVERRUN_IRQ_EN(x) ((x) << 17)
#define DATA_IRQ_EN(x) ((x) << 16)
#define TP_DATA_XY_CHANGE(x) ((x) << 13)
#define FIFO_TRIG(x) ((x) << 8) / 5 bits /
#define DATA_DRQ_EN(x) ((x) << 7)
#define FIFO_FLUSH(x) ((x) << 4)
#define TP_UP_IRQ_EN(x) ((x) << 1)
#define TP_DOWN_IRQ_EN(x) ((x) << 0)

/ TP_INT_FIFOS irq and fifo status bits /
#define TEMP_DATA_PENDING BIT(18)
#define FIFO_OVERRUN_PENDING BIT(17)
#define FIFO_DATA_PENDING BIT(16)
#define TP_IDLE_FLG BIT(2)
#define TP_UP_PENDING BIT(1)
#define TP_DOWN_PENDING BIT(0)

/ TP_TPR bits /
#define TEMP_ENABLE(x) ((x) << 16)
#define TEMP_PERIOD(x) ((x) << 0) / t = x 256 16 / clkin /

struct sun4i_ts_data {
struct device *dev;
struct input_dev *input;
void __iomem *base;
unsigned int irq;
bool ignore_fifo_data;
int temp_data;
int temp_offset;
int temp_step;
};

static void sun4i_ts_irq_handle_input(struct sun4i_ts_data *ts, u32 reg_val)
{
u32 x, y;

if (reg_val & FIFO_DATA_PENDING) {
x = readl(ts->base + TP_DATA);
y = readl(ts->base + TP_DATA);
/ The 1st location reported after an up event is unreliable /
if (!ts->ignore_fifo_data) {
input_report_abs(ts->input, ABS_X, x);
input_report_abs(ts->input, ABS_Y, y);
/*

• The hardware has a separate down status bit, but

• that gets set before we get the first location,

• resulting in reporting a click on the old location.
  */
  input_report_key(ts->input, BTN_TOUCH, 1);
  input_sync(ts->input);
  } else {
  ts->ignore_fifo_data = false;
  }
  }

if (reg_val & TP_UP_PENDING) {
ts->ignore_fifo_data = true;
input_report_key(ts->input, BTN_TOUCH, 0);
input_sync(ts->input);
}
}

static irqreturn_t sun4i_ts_irq(int irq, void *dev_id)
{
struct sun4i_ts_data *ts = dev_id;
u32 reg_val;

reg_val = readl(ts->base + TP_INT_FIFOS);

if (reg_val & TEMP_DATA_PENDING)
ts->temp_data = readl(ts->base + TEMP_DATA);

if (ts->input)
sun4i_ts_irq_handle_input(ts, reg_val);

writel(reg_val, ts->base + TP_INT_FIFOS);

return IRQ_HANDLED;
}

static int sun4i_ts_open(struct input_dev *dev)
{
struct sun4i_ts_data *ts = input_get_drvdata(dev);

/ Flush, set trig level to 1, enable temp, data and up irqs /
writel(TEMP_IRQ_EN(1) | DATA_IRQ_EN(1) | FIFO_TRIG(1) | FIFO_FLUSH(1) |
TP_UP_IRQ_EN(1), ts->base + TP_INT_FIFOC);

return 0;
}

static void sun4i_ts_close(struct input_dev *dev)
{
struct sun4i_ts_data *ts = input_get_drvdata(dev);

/ Deactivate all input IRQs /
writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);
}

static int sun4i_get_temp(const struct sun4i_ts_data ts, int temp)
{
/ No temp_data until the first irq /
if (ts->temp_data == -1)
return -EAGAIN;

temp = ts->temp_data ts->temp_step - ts->temp_offset;

return 0;
}

static int sun4i_get_tz_temp(void data, int temp)
{
return sun4i_get_temp(data, temp);
}

static const struct thermal_zone_of_device_ops sun4i_ts_tz_ops = {
.get_temp = sun4i_get_tz_temp,
};

static ssize_t show_temp(struct device dev, struct device_attribute devattr,
char *buf)
{
struct sun4i_ts_data *ts = dev_get_drvdata(dev);
int temp;
int error;

error = sun4i_get_temp(ts, &temp);
if (error)
return error;

return sprintf(buf, "%d\n", temp);
}

static ssize_t show_temp_label(struct device *dev,
struct device_attribute devattr, char buf)
{
return sprintf(buf, "SoC temperature\n");
}

static DEVICE_ATTR(temp1_input, S_IRUGO, show_temp, NULL);
static DEVICE_ATTR(temp1_label, S_IRUGO, show_temp_label, NULL);

static struct attribute *sun4i_ts_attrs[] = {
&dev_attr_temp1_input.attr,
&dev_attr_temp1_label.attr,
NULL
};
ATTRIBUTE_GROUPS(sun4i_ts);

static int sun4i_ts_probe(struct platform_device *pdev)
{
struct sun4i_ts_data *ts;
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct device *hwmon;
int error;
u32 reg;
bool ts_attached;
u32 tp_sensitive_adjust = 15;
u32 filter_type = 1;

ts = devm_kzalloc(dev, sizeof(struct sun4i_ts_data), GFP_KERNEL);
if (!ts)
return -ENOMEM;

ts->dev = dev;
ts->ignore_fifo_data = true;
ts->temp_data = -1;
if (of_device_is_compatible(np, "allwinner,sun6i-a31-ts")) {
/ Allwinner SDK has temperature (C) = (value / 6) - 271 /
ts->temp_offset = 271000;
ts->temp_step = 167;
} else if (of_device_is_compatible(np, "allwinner,sun4i-a10-ts")) {
/*

• The A10 temperature sensor has quite a wide spread, these

• parameters are based on the averaging of the calibration

• results of 4 completely different boards, with a spread of

• temp_step from 0.096 - 0.170 and temp_offset from 176 - 331.
  */
  ts->temp_offset = 257000;
  ts->temp_step = 133;
  } else {
  /*

• The user manuals do not contain the formula for calculating

• the temperature. The formula used here is from the AXP209,

• which is designed by X-Powers, an affiliate of Allwinner:
  *

• temperature (C) = (value * 0.1) - 144.7
  *

• Allwinner does not have any documentation whatsoever for

• this hardware. Moreover, it is claimed that the sensor

• is inaccurate and cannot work properly.
  */
  ts->temp_offset = 144700;
  ts->temp_step = 100;
  }

ts_attached = of_property_read_bool(np, "allwinner,ts-attached");
if (ts_attached) {
ts->input = devm_input_allocate_device(dev);
if (!ts->input)
return -ENOMEM;

ts->input->name = pdev->name;
ts->input->phys = "sun4i_ts/input0";
ts->input->open = sun4i_ts_open;
ts->input->close = sun4i_ts_close;
ts->input->id.bustype = BUS_HOST;
ts->input->id.vendor = 0x0001;
ts->input->id.product = 0x0001;
ts->input->id.version = 0x0100;
ts->input->evbit[0] = BIT(EV_SYN) | BIT(EV_KEY) | BIT(EV_ABS);
__set_bit(BTN_TOUCH, ts->input->keybit);
input_set_abs_params(ts->input, ABS_X, 0, 4095, 0, 0);
input_set_abs_params(ts->input, ABS_Y, 0, 4095, 0, 0);
input_set_drvdata(ts->input, ts);
}

ts->base = devm_ioremap_resource(dev,
platform_get_resource(pdev, IORESOURCE_MEM, 0));
if (IS_ERR(ts->base))
return PTR_ERR(ts->base);

ts->irq = platform_get_irq(pdev, 0);
error = devm_request_irq(dev, ts->irq, sun4i_ts_irq, 0, "sun4i-ts", ts);
if (error)
return error;

/*

• Select HOSC clk, clkin = clk / 6, adc samplefreq = clkin / 8192,

• t_acq = clkin / (16 * 64)
  */
  writel(ADC_CLK_SEL(0) | ADC_CLK_DIV(2) | FS_DIV(7) | T_ACQ(63),
  ts->base + TP_CTRL0);

/*

• tp_sensitive_adjust is an optional property

• tp_mode = 0 : only x and y coordinates, as we don't use dual touch
  */
  of_property_read_u32(np, "allwinner,tp-sensitive-adjust",
  &tp_sensitive_adjust);
  writel(TP_SENSITIVE_ADJUST(tp_sensitive_adjust) | TP_MODE_SELECT(0),
  ts->base + TP_CTRL2);

/*

• Enable median and averaging filter, optional property for

• filter type.
  */
  of_property_read_u32(np, "allwinner,filter-type", &filter_type);
  writel(FILTER_EN(1) | FILTER_TYPE(filter_type), ts->base + TP_CTRL3);

/ Enable temperature measurement, period 1953 (2 seconds) /
writel(TEMP_ENABLE(1) | TEMP_PERIOD(1953), ts->base + TP_TPR);

/*

• Set stylus up debounce to aprox 10 ms, enable debounce, and

• finally enable tp mode.
  */
  reg = STYLUS_UP_DEBOUN(5) | STYLUS_UP_DEBOUN_EN(1);
  if (of_device_is_compatible(np, "allwinner,sun6i-a31-ts"))
  reg |= SUN6I_TP_MODE_EN(1);
  else
  reg |= TP_MODE_EN(1);
  writel(reg, ts->base + TP_CTRL1);

/*

• The thermal core does not register hwmon devices for DT-based

• thermal zone sensors, such as this one.
  */
  hwmon = devm_hwmon_device_register_with_groups(ts->dev, "sun4i_ts",
  ts, sun4i_ts_groups);
  if (IS_ERR(hwmon))
  return PTR_ERR(hwmon);

devm_thermal_zone_of_sensor_register(ts->dev, 0, ts, &sun4i_ts_tz_ops);

writel(TEMP_IRQ_EN(1), ts->base + TP_INT_FIFOC);

if (ts_attached) {
error = input_register_device(ts->input);
if (error) {
writel(0, ts->base + TP_INT_FIFOC);
return error;
}
}

platform_set_drvdata(pdev, ts);
return 0;
}

static int sun4i_ts_remove(struct platform_device *pdev)
{
struct sun4i_ts_data *ts = platform_get_drvdata(pdev);

/ Explicit unregister to avoid open/close changing the imask later /
if (ts->input)
input_unregister_device(ts->input);

/ Deactivate all IRQs /
writel(0, ts->base + TP_INT_FIFOC);

return 0;
}

static const struct of_device_id sun4i_ts_of_match[] = {
{ .compatible = "allwinner,sun4i-a10-ts", },
{ .compatible = "allwinner,sun5i-a13-ts", },
{ .compatible = "allwinner,sun6i-a31-ts", },
{ / sentinel / }
};
MODULE_DEVICE_TABLE(of, sun4i_ts_of_match);

static struct platform_driver sun4i_ts_driver = {
.driver = {
.name = "sun4i-ts",
.of_match_table = of_match_ptr(sun4i_ts_of_match),
},
.probe = sun4i_ts_probe,
.remove = sun4i_ts_remove,
};

module_platform_driver(sun4i_ts_driver);

MODULE_DESCRIPTION("Allwinner sun4i resistive touchscreen controller driver");
MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
MODULE_LICENSE("GPL");