2 * Allwinner sunxi resistive touchscreen controller driver
4 * Copyright (C) 2013 - 2014 Hans de Goede <hdegoede@redhat.com>
6 * The hwmon parts are based on work by Corentin LABBE which is:
7 * Copyright (C) 2013 Corentin LABBE <clabbe.montjoie@gmail.com>
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
21 * The sun4i-ts controller is capable of detecting a second touch, but when a
22 * second touch is present then the accuracy becomes so bad the reported touch
23 * location is not useable.
25 * The original android driver contains some complicated heuristics using the
26 * aprox. distance between the 2 touches to see if the user is making a pinch
27 * open / close movement, and then reports emulated multi-touch events around
28 * the last touch coordinate (as the dual-touch coordinates are worthless).
30 * These kinds of heuristics are just asking for trouble (and don't belong
31 * in the kernel). So this driver offers straight forward, reliable single
32 * touch functionality only.
34 * s.a. A20 User Manual "1.15 TP" (Documentation/arm/sunxi/README)
35 * (looks like the description in the A20 User Manual v1.3 is better
36 * than the one in the A10 User Manual v.1.5)
39 #include <linux/err.h>
40 #include <linux/hwmon.h>
41 #include <linux/thermal.h>
42 #include <linux/init.h>
43 #include <linux/input.h>
44 #include <linux/interrupt.h>
46 #include <linux/module.h>
47 #include <linux/of_platform.h>
48 #include <linux/platform_device.h>
49 #include <linux/slab.h>
55 #define TP_INT_FIFOC 0x10
56 #define TP_INT_FIFOS 0x14
59 #define TEMP_DATA 0x20
63 #define ADC_FIRST_DLY(x) ((x) << 24) /* 8 bits */
64 #define ADC_FIRST_DLY_MODE(x) ((x) << 23)
65 #define ADC_CLK_SEL(x) ((x) << 22)
66 #define ADC_CLK_DIV(x) ((x) << 20) /* 3 bits */
67 #define FS_DIV(x) ((x) << 16) /* 4 bits */
68 #define T_ACQ(x) ((x) << 0) /* 16 bits */
71 #define STYLUS_UP_DEBOUN(x) ((x) << 12) /* 8 bits */
72 #define STYLUS_UP_DEBOUN_EN(x) ((x) << 9)
73 #define TOUCH_PAN_CALI_EN(x) ((x) << 6)
74 #define TP_DUAL_EN(x) ((x) << 5)
75 #define TP_MODE_EN(x) ((x) << 4)
76 #define TP_ADC_SELECT(x) ((x) << 3)
77 #define ADC_CHAN_SELECT(x) ((x) << 0) /* 3 bits */
79 /* on sun6i, bits 3~6 are left shifted by 1 to 4~7 */
80 #define SUN6I_TP_MODE_EN(x) ((x) << 5)
83 #define TP_SENSITIVE_ADJUST(x) ((x) << 28) /* 4 bits */
84 #define TP_MODE_SELECT(x) ((x) << 26) /* 2 bits */
85 #define PRE_MEA_EN(x) ((x) << 24)
86 #define PRE_MEA_THRE_CNT(x) ((x) << 0) /* 24 bits */
89 #define FILTER_EN(x) ((x) << 2)
90 #define FILTER_TYPE(x) ((x) << 0) /* 2 bits */
92 /* TP_INT_FIFOC irq and fifo mask / control bits */
93 #define TEMP_IRQ_EN(x) ((x) << 18)
94 #define OVERRUN_IRQ_EN(x) ((x) << 17)
95 #define DATA_IRQ_EN(x) ((x) << 16)
96 #define TP_DATA_XY_CHANGE(x) ((x) << 13)
97 #define FIFO_TRIG(x) ((x) << 8) /* 5 bits */
98 #define DATA_DRQ_EN(x) ((x) << 7)
99 #define FIFO_FLUSH(x) ((x) << 4)
100 #define TP_UP_IRQ_EN(x) ((x) << 1)
101 #define TP_DOWN_IRQ_EN(x) ((x) << 0)
103 /* TP_INT_FIFOS irq and fifo status bits */
104 #define TEMP_DATA_PENDING BIT(18)
105 #define FIFO_OVERRUN_PENDING BIT(17)
106 #define FIFO_DATA_PENDING BIT(16)
107 #define TP_IDLE_FLG BIT(2)
108 #define TP_UP_PENDING BIT(1)
109 #define TP_DOWN_PENDING BIT(0)
112 #define TEMP_ENABLE(x) ((x) << 16)
113 #define TEMP_PERIOD(x) ((x) << 0) /* t = x * 256 * 16 / clkin */
115 struct sun4i_ts_data
{
117 struct input_dev
*input
;
120 bool ignore_fifo_data
;
126 static void sun4i_ts_irq_handle_input(struct sun4i_ts_data
*ts
, u32 reg_val
)
130 if (reg_val
& FIFO_DATA_PENDING
) {
131 x
= readl(ts
->base
+ TP_DATA
);
132 y
= readl(ts
->base
+ TP_DATA
);
133 /* The 1st location reported after an up event is unreliable */
134 if (!ts
->ignore_fifo_data
) {
135 input_report_abs(ts
->input
, ABS_X
, x
);
136 input_report_abs(ts
->input
, ABS_Y
, y
);
138 * The hardware has a separate down status bit, but
139 * that gets set before we get the first location,
140 * resulting in reporting a click on the old location.
142 input_report_key(ts
->input
, BTN_TOUCH
, 1);
143 input_sync(ts
->input
);
145 ts
->ignore_fifo_data
= false;
149 if (reg_val
& TP_UP_PENDING
) {
150 ts
->ignore_fifo_data
= true;
151 input_report_key(ts
->input
, BTN_TOUCH
, 0);
152 input_sync(ts
->input
);
156 static irqreturn_t
sun4i_ts_irq(int irq
, void *dev_id
)
158 struct sun4i_ts_data
*ts
= dev_id
;
161 reg_val
= readl(ts
->base
+ TP_INT_FIFOS
);
163 if (reg_val
& TEMP_DATA_PENDING
)
164 ts
->temp_data
= readl(ts
->base
+ TEMP_DATA
);
167 sun4i_ts_irq_handle_input(ts
, reg_val
);
169 writel(reg_val
, ts
->base
+ TP_INT_FIFOS
);
174 static int sun4i_ts_open(struct input_dev
*dev
)
176 struct sun4i_ts_data
*ts
= input_get_drvdata(dev
);
178 /* Flush, set trig level to 1, enable temp, data and up irqs */
179 writel(TEMP_IRQ_EN(1) | DATA_IRQ_EN(1) | FIFO_TRIG(1) | FIFO_FLUSH(1) |
180 TP_UP_IRQ_EN(1), ts
->base
+ TP_INT_FIFOC
);
185 static void sun4i_ts_close(struct input_dev
*dev
)
187 struct sun4i_ts_data
*ts
= input_get_drvdata(dev
);
189 /* Deactivate all input IRQs */
190 writel(TEMP_IRQ_EN(1), ts
->base
+ TP_INT_FIFOC
);
193 static int sun4i_get_temp(const struct sun4i_ts_data
*ts
, int *temp
)
195 /* No temp_data until the first irq */
196 if (ts
->temp_data
== -1)
199 *temp
= ts
->temp_data
* ts
->temp_step
- ts
->temp_offset
;
204 static int sun4i_get_tz_temp(void *data
, int *temp
)
206 return sun4i_get_temp(data
, temp
);
209 static struct thermal_zone_of_device_ops sun4i_ts_tz_ops
= {
210 .get_temp
= sun4i_get_tz_temp
,
213 static ssize_t
show_temp(struct device
*dev
, struct device_attribute
*devattr
,
216 struct sun4i_ts_data
*ts
= dev_get_drvdata(dev
);
220 error
= sun4i_get_temp(ts
, &temp
);
224 return sprintf(buf
, "%d\n", temp
);
227 static ssize_t
show_temp_label(struct device
*dev
,
228 struct device_attribute
*devattr
, char *buf
)
230 return sprintf(buf
, "SoC temperature\n");
233 static DEVICE_ATTR(temp1_input
, S_IRUGO
, show_temp
, NULL
);
234 static DEVICE_ATTR(temp1_label
, S_IRUGO
, show_temp_label
, NULL
);
236 static struct attribute
*sun4i_ts_attrs
[] = {
237 &dev_attr_temp1_input
.attr
,
238 &dev_attr_temp1_label
.attr
,
241 ATTRIBUTE_GROUPS(sun4i_ts
);
243 static int sun4i_ts_probe(struct platform_device
*pdev
)
245 struct sun4i_ts_data
*ts
;
246 struct device
*dev
= &pdev
->dev
;
247 struct device_node
*np
= dev
->of_node
;
248 struct device
*hwmon
;
252 u32 tp_sensitive_adjust
= 15;
255 ts
= devm_kzalloc(dev
, sizeof(struct sun4i_ts_data
), GFP_KERNEL
);
260 ts
->ignore_fifo_data
= true;
262 if (of_device_is_compatible(np
, "allwinner,sun6i-a31-ts")) {
263 /* Allwinner SDK has temperature (C) = (value / 6) - 271 */
264 ts
->temp_offset
= 271000;
266 } else if (of_device_is_compatible(np
, "allwinner,sun4i-a10-ts")) {
268 * The A10 temperature sensor has quite a wide spread, these
269 * parameters are based on the averaging of the calibration
270 * results of 4 completely different boards, with a spread of
271 * temp_step from 0.096 - 0.170 and temp_offset from 176 - 331.
273 ts
->temp_offset
= 257000;
277 * The user manuals do not contain the formula for calculating
278 * the temperature. The formula used here is from the AXP209,
279 * which is designed by X-Powers, an affiliate of Allwinner:
281 * temperature (C) = (value * 0.1) - 144.7
283 * Allwinner does not have any documentation whatsoever for
284 * this hardware. Moreover, it is claimed that the sensor
285 * is inaccurate and cannot work properly.
287 ts
->temp_offset
= 144700;
291 ts_attached
= of_property_read_bool(np
, "allwinner,ts-attached");
293 ts
->input
= devm_input_allocate_device(dev
);
297 ts
->input
->name
= pdev
->name
;
298 ts
->input
->phys
= "sun4i_ts/input0";
299 ts
->input
->open
= sun4i_ts_open
;
300 ts
->input
->close
= sun4i_ts_close
;
301 ts
->input
->id
.bustype
= BUS_HOST
;
302 ts
->input
->id
.vendor
= 0x0001;
303 ts
->input
->id
.product
= 0x0001;
304 ts
->input
->id
.version
= 0x0100;
305 ts
->input
->evbit
[0] = BIT(EV_SYN
) | BIT(EV_KEY
) | BIT(EV_ABS
);
306 __set_bit(BTN_TOUCH
, ts
->input
->keybit
);
307 input_set_abs_params(ts
->input
, ABS_X
, 0, 4095, 0, 0);
308 input_set_abs_params(ts
->input
, ABS_Y
, 0, 4095, 0, 0);
309 input_set_drvdata(ts
->input
, ts
);
312 ts
->base
= devm_ioremap_resource(dev
,
313 platform_get_resource(pdev
, IORESOURCE_MEM
, 0));
314 if (IS_ERR(ts
->base
))
315 return PTR_ERR(ts
->base
);
317 ts
->irq
= platform_get_irq(pdev
, 0);
318 error
= devm_request_irq(dev
, ts
->irq
, sun4i_ts_irq
, 0, "sun4i-ts", ts
);
323 * Select HOSC clk, clkin = clk / 6, adc samplefreq = clkin / 8192,
324 * t_acq = clkin / (16 * 64)
326 writel(ADC_CLK_SEL(0) | ADC_CLK_DIV(2) | FS_DIV(7) | T_ACQ(63),
327 ts
->base
+ TP_CTRL0
);
330 * tp_sensitive_adjust is an optional property
331 * tp_mode = 0 : only x and y coordinates, as we don't use dual touch
333 of_property_read_u32(np
, "allwinner,tp-sensitive-adjust",
334 &tp_sensitive_adjust
);
335 writel(TP_SENSITIVE_ADJUST(tp_sensitive_adjust
) | TP_MODE_SELECT(0),
336 ts
->base
+ TP_CTRL2
);
339 * Enable median and averaging filter, optional property for
342 of_property_read_u32(np
, "allwinner,filter-type", &filter_type
);
343 writel(FILTER_EN(1) | FILTER_TYPE(filter_type
), ts
->base
+ TP_CTRL3
);
345 /* Enable temperature measurement, period 1953 (2 seconds) */
346 writel(TEMP_ENABLE(1) | TEMP_PERIOD(1953), ts
->base
+ TP_TPR
);
349 * Set stylus up debounce to aprox 10 ms, enable debounce, and
350 * finally enable tp mode.
352 reg
= STYLUS_UP_DEBOUN(5) | STYLUS_UP_DEBOUN_EN(1);
353 if (of_device_is_compatible(np
, "allwinner,sun6i-a31-ts"))
354 reg
|= SUN6I_TP_MODE_EN(1);
356 reg
|= TP_MODE_EN(1);
357 writel(reg
, ts
->base
+ TP_CTRL1
);
360 * The thermal core does not register hwmon devices for DT-based
361 * thermal zone sensors, such as this one.
363 hwmon
= devm_hwmon_device_register_with_groups(ts
->dev
, "sun4i_ts",
364 ts
, sun4i_ts_groups
);
366 return PTR_ERR(hwmon
);
368 devm_thermal_zone_of_sensor_register(ts
->dev
, 0, ts
, &sun4i_ts_tz_ops
);
370 writel(TEMP_IRQ_EN(1), ts
->base
+ TP_INT_FIFOC
);
373 error
= input_register_device(ts
->input
);
375 writel(0, ts
->base
+ TP_INT_FIFOC
);
380 platform_set_drvdata(pdev
, ts
);
384 static int sun4i_ts_remove(struct platform_device
*pdev
)
386 struct sun4i_ts_data
*ts
= platform_get_drvdata(pdev
);
388 /* Explicit unregister to avoid open/close changing the imask later */
390 input_unregister_device(ts
->input
);
392 /* Deactivate all IRQs */
393 writel(0, ts
->base
+ TP_INT_FIFOC
);
398 static const struct of_device_id sun4i_ts_of_match
[] = {
399 { .compatible
= "allwinner,sun4i-a10-ts", },
400 { .compatible
= "allwinner,sun5i-a13-ts", },
401 { .compatible
= "allwinner,sun6i-a31-ts", },
404 MODULE_DEVICE_TABLE(of
, sun4i_ts_of_match
);
406 static struct platform_driver sun4i_ts_driver
= {
409 .of_match_table
= of_match_ptr(sun4i_ts_of_match
),
411 .probe
= sun4i_ts_probe
,
412 .remove
= sun4i_ts_remove
,
415 module_platform_driver(sun4i_ts_driver
);
417 MODULE_DESCRIPTION("Allwinner sun4i resistive touchscreen controller driver");
418 MODULE_AUTHOR("Hans de Goede <hdegoede@redhat.com>");
419 MODULE_LICENSE("GPL");