--- /dev/null
+/*
+ * Allwinner sunxi resistive touchscreen controller driver
+ *
+ * Copyright (C) 2013 - 2014 Hans de Goede <hdegoede@redhat.com>
+ *
+ * The hwmon parts are based on work by Corentin LABBE which is:
+ * Copyright (C) 2013 Corentin LABBE <clabbe.montjoie@gmail.com>
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+/*
+ * The sun4i-ts controller is capable of detecting a second touch, but when a
+ * second touch is present then the accuracy becomes so bad the reported touch
+ * location is not useable.
+ *
+ * The original android driver contains some complicated heuristics using the
+ * aprox. distance between the 2 touches to see if the user is making a pinch
+ * open / close movement, and then reports emulated multi-touch events around
+ * the last touch coordinate (as the dual-touch coordinates are worthless).
+ *
+ * These kinds of heuristics are just asking for trouble (and don't belong
+ * in the kernel). So this driver offers straight forward, reliable single
+ * touch functionality only.
+ *
+ * s.a. A20 User Manual "1.15 TP" (Documentation/arm/sunxi/README)
+ * (looks like the description in the A20 User Manual v1.3 is better
+ * than the one in the A10 User Manual v.1.5)
+ */
+
+#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;
+ struct thermal_zone_device *tz;
+ 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, long *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, long *temp)
+{
+ return sun4i_get_temp(data, temp);
+}
+
+static 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);
+ long temp;
+ int error;
+
+ error = sun4i_get_temp(ts, &temp);
+ if (error)
+ return error;
+
+ return sprintf(buf, "%ld\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);
+
+ ts->tz = thermal_zone_of_sensor_register(ts->dev, 0, ts,
+ &sun4i_ts_tz_ops);
+ if (IS_ERR(ts->tz))
+ ts->tz = NULL;
+
+ 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);
+ thermal_zone_of_sensor_unregister(ts->dev, ts->tz);
+ 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);
+
+ thermal_zone_of_sensor_unregister(ts->dev, ts->tz);
+
+ /* 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");
Code Review / kvmfornfv.git / blobdiff