Commit | Line | Data |
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75259966 | 1 | /* |
75259966 TF |
2 | * Touchscreen driver for the tps6507x chip. |
3 | * | |
4 | * Copyright (c) 2009 RidgeRun (todd.fischer@ridgerun.com) | |
5 | * | |
6 | * Credits: | |
7 | * | |
8 | * Using code from tsc2007, MtekVision Co., Ltd. | |
9 | * | |
10 | * For licencing details see kernel-base/COPYING | |
11 | * | |
12 | * TPS65070, TPS65073, TPS650731, and TPS650732 support | |
13 | * 10 bit touch screen interface. | |
14 | */ | |
15 | ||
16 | #include <linux/module.h> | |
17 | #include <linux/workqueue.h> | |
18 | #include <linux/slab.h> | |
19 | #include <linux/input.h> | |
20 | #include <linux/platform_device.h> | |
21 | #include <linux/mfd/tps6507x.h> | |
22 | #include <linux/input/tps6507x-ts.h> | |
23 | #include <linux/delay.h> | |
24 | ||
25 | #define TSC_DEFAULT_POLL_PERIOD 30 /* ms */ | |
26 | #define TPS_DEFAULT_MIN_PRESSURE 0x30 | |
27 | #define MAX_10BIT ((1 << 10) - 1) | |
28 | ||
29 | #define TPS6507X_ADCONFIG_CONVERT_TS (TPS6507X_ADCONFIG_AD_ENABLE | \ | |
30 | TPS6507X_ADCONFIG_START_CONVERSION | \ | |
31 | TPS6507X_ADCONFIG_INPUT_REAL_TSC) | |
32 | #define TPS6507X_ADCONFIG_POWER_DOWN_TS (TPS6507X_ADCONFIG_INPUT_REAL_TSC) | |
33 | ||
34 | struct ts_event { | |
35 | u16 x; | |
36 | u16 y; | |
37 | u16 pressure; | |
38 | }; | |
39 | ||
40 | struct tps6507x_ts { | |
75259966 | 41 | struct device *dev; |
7cca5a34 | 42 | struct input_dev *input; |
5705b8ac | 43 | struct tps6507x_dev *mfd; |
75259966 | 44 | char phys[32]; |
75259966 | 45 | struct ts_event tc; |
02a71600 | 46 | u16 min_pressure; |
02a71600 | 47 | bool pendown; |
75259966 TF |
48 | }; |
49 | ||
50 | static int tps6507x_read_u8(struct tps6507x_ts *tsc, u8 reg, u8 *data) | |
51 | { | |
e5e66ed0 | 52 | return tsc->mfd->read_dev(tsc->mfd, reg, 1, data); |
75259966 TF |
53 | } |
54 | ||
55 | static int tps6507x_write_u8(struct tps6507x_ts *tsc, u8 reg, u8 data) | |
56 | { | |
57 | return tsc->mfd->write_dev(tsc->mfd, reg, 1, &data); | |
58 | } | |
59 | ||
60 | static s32 tps6507x_adc_conversion(struct tps6507x_ts *tsc, | |
61 | u8 tsc_mode, u16 *value) | |
62 | { | |
63 | s32 ret; | |
64 | u8 adc_status; | |
65 | u8 result; | |
66 | ||
67 | /* Route input signal to A/D converter */ | |
68 | ||
69 | ret = tps6507x_write_u8(tsc, TPS6507X_REG_TSCMODE, tsc_mode); | |
70 | if (ret) { | |
71 | dev_err(tsc->dev, "TSC mode read failed\n"); | |
72 | goto err; | |
73 | } | |
74 | ||
75 | /* Start A/D conversion */ | |
76 | ||
77 | ret = tps6507x_write_u8(tsc, TPS6507X_REG_ADCONFIG, | |
78 | TPS6507X_ADCONFIG_CONVERT_TS); | |
79 | if (ret) { | |
80 | dev_err(tsc->dev, "ADC config write failed\n"); | |
81 | return ret; | |
82 | } | |
83 | ||
84 | do { | |
85 | ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADCONFIG, | |
86 | &adc_status); | |
87 | if (ret) { | |
88 | dev_err(tsc->dev, "ADC config read failed\n"); | |
89 | goto err; | |
90 | } | |
91 | } while (adc_status & TPS6507X_ADCONFIG_START_CONVERSION); | |
92 | ||
93 | ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADRESULT_2, &result); | |
94 | if (ret) { | |
95 | dev_err(tsc->dev, "ADC result 2 read failed\n"); | |
96 | goto err; | |
97 | } | |
98 | ||
99 | *value = (result & TPS6507X_REG_ADRESULT_2_MASK) << 8; | |
100 | ||
101 | ret = tps6507x_read_u8(tsc, TPS6507X_REG_ADRESULT_1, &result); | |
102 | if (ret) { | |
103 | dev_err(tsc->dev, "ADC result 1 read failed\n"); | |
104 | goto err; | |
105 | } | |
106 | ||
107 | *value |= result; | |
108 | ||
109 | dev_dbg(tsc->dev, "TSC channel %d = 0x%X\n", tsc_mode, *value); | |
110 | ||
111 | err: | |
112 | return ret; | |
113 | } | |
114 | ||
115 | /* Need to call tps6507x_adc_standby() after using A/D converter for the | |
116 | * touch screen interrupt to work properly. | |
117 | */ | |
118 | ||
119 | static s32 tps6507x_adc_standby(struct tps6507x_ts *tsc) | |
120 | { | |
121 | s32 ret; | |
75259966 TF |
122 | u8 val; |
123 | ||
124 | ret = tps6507x_write_u8(tsc, TPS6507X_REG_ADCONFIG, | |
125 | TPS6507X_ADCONFIG_INPUT_TSC); | |
126 | if (ret) | |
127 | return ret; | |
128 | ||
129 | ret = tps6507x_write_u8(tsc, TPS6507X_REG_TSCMODE, | |
130 | TPS6507X_TSCMODE_STANDBY); | |
131 | if (ret) | |
132 | return ret; | |
133 | ||
134 | ret = tps6507x_read_u8(tsc, TPS6507X_REG_INT, &val); | |
135 | if (ret) | |
136 | return ret; | |
137 | ||
138 | while (val & TPS6507X_REG_TSC_INT) { | |
139 | mdelay(10); | |
140 | ret = tps6507x_read_u8(tsc, TPS6507X_REG_INT, &val); | |
141 | if (ret) | |
142 | return ret; | |
75259966 TF |
143 | } |
144 | ||
145 | return ret; | |
146 | } | |
147 | ||
7cca5a34 | 148 | static void tps6507x_ts_poll(struct input_dev *input_dev) |
75259966 | 149 | { |
7cca5a34 | 150 | struct tps6507x_ts *tsc = input_get_drvdata(input_dev); |
02a71600 | 151 | bool pendown; |
75259966 TF |
152 | s32 ret; |
153 | ||
02a71600 DT |
154 | ret = tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_PRESSURE, |
155 | &tsc->tc.pressure); | |
75259966 TF |
156 | if (ret) |
157 | goto done; | |
158 | ||
159 | pendown = tsc->tc.pressure > tsc->min_pressure; | |
160 | ||
161 | if (unlikely(!pendown && tsc->pendown)) { | |
162 | dev_dbg(tsc->dev, "UP\n"); | |
163 | input_report_key(input_dev, BTN_TOUCH, 0); | |
164 | input_report_abs(input_dev, ABS_PRESSURE, 0); | |
165 | input_sync(input_dev); | |
02a71600 | 166 | tsc->pendown = false; |
75259966 TF |
167 | } |
168 | ||
169 | if (pendown) { | |
170 | ||
171 | if (!tsc->pendown) { | |
172 | dev_dbg(tsc->dev, "DOWN\n"); | |
173 | input_report_key(input_dev, BTN_TOUCH, 1); | |
174 | } else | |
175 | dev_dbg(tsc->dev, "still down\n"); | |
176 | ||
177 | ret = tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_X_POSITION, | |
178 | &tsc->tc.x); | |
179 | if (ret) | |
180 | goto done; | |
181 | ||
182 | ret = tps6507x_adc_conversion(tsc, TPS6507X_TSCMODE_Y_POSITION, | |
183 | &tsc->tc.y); | |
184 | if (ret) | |
185 | goto done; | |
186 | ||
187 | input_report_abs(input_dev, ABS_X, tsc->tc.x); | |
188 | input_report_abs(input_dev, ABS_Y, tsc->tc.y); | |
189 | input_report_abs(input_dev, ABS_PRESSURE, tsc->tc.pressure); | |
190 | input_sync(input_dev); | |
02a71600 | 191 | tsc->pendown = true; |
75259966 TF |
192 | } |
193 | ||
194 | done: | |
5705b8ac | 195 | tps6507x_adc_standby(tsc); |
75259966 TF |
196 | } |
197 | ||
198 | static int tps6507x_ts_probe(struct platform_device *pdev) | |
199 | { | |
75259966 | 200 | struct tps6507x_dev *tps6507x_dev = dev_get_drvdata(pdev->dev.parent); |
5705b8ac DT |
201 | const struct tps6507x_board *tps_board; |
202 | const struct touchscreen_init_data *init_data; | |
203 | struct tps6507x_ts *tsc; | |
75259966 | 204 | struct input_dev *input_dev; |
5705b8ac | 205 | int error; |
75259966 | 206 | |
5705b8ac | 207 | /* |
75259966 TF |
208 | * tps_board points to pmic related constants |
209 | * coming from the board-evm file. | |
210 | */ | |
5705b8ac | 211 | tps_board = dev_get_platdata(tps6507x_dev->dev); |
75259966 TF |
212 | if (!tps_board) { |
213 | dev_err(tps6507x_dev->dev, | |
214 | "Could not find tps6507x platform data\n"); | |
5705b8ac | 215 | return -ENODEV; |
75259966 TF |
216 | } |
217 | ||
5705b8ac | 218 | /* |
75259966 TF |
219 | * init_data points to array of regulator_init structures |
220 | * coming from the board-evm file. | |
221 | */ | |
75259966 TF |
222 | init_data = tps_board->tps6507x_ts_init_data; |
223 | ||
2e2a0db8 | 224 | tsc = devm_kzalloc(&pdev->dev, sizeof(struct tps6507x_ts), GFP_KERNEL); |
75259966 TF |
225 | if (!tsc) { |
226 | dev_err(tps6507x_dev->dev, "failed to allocate driver data\n"); | |
5705b8ac | 227 | return -ENOMEM; |
75259966 TF |
228 | } |
229 | ||
75259966 TF |
230 | tsc->mfd = tps6507x_dev; |
231 | tsc->dev = tps6507x_dev->dev; | |
5705b8ac DT |
232 | tsc->min_pressure = init_data ? |
233 | init_data->min_pressure : TPS_DEFAULT_MIN_PRESSURE; | |
234 | ||
235 | snprintf(tsc->phys, sizeof(tsc->phys), | |
236 | "%s/input0", dev_name(tsc->dev)); | |
237 | ||
7cca5a34 DT |
238 | input_dev = devm_input_allocate_device(&pdev->dev); |
239 | if (!input_dev) { | |
5705b8ac | 240 | dev_err(tsc->dev, "Failed to allocate polled input device.\n"); |
2e2a0db8 | 241 | return -ENOMEM; |
75259966 TF |
242 | } |
243 | ||
7cca5a34 DT |
244 | tsc->input = input_dev; |
245 | input_set_drvdata(input_dev, tsc); | |
75259966 | 246 | |
7cca5a34 | 247 | input_set_capability(input_dev, EV_KEY, BTN_TOUCH); |
75259966 TF |
248 | input_set_abs_params(input_dev, ABS_X, 0, MAX_10BIT, 0, 0); |
249 | input_set_abs_params(input_dev, ABS_Y, 0, MAX_10BIT, 0, 0); | |
250 | input_set_abs_params(input_dev, ABS_PRESSURE, 0, MAX_10BIT, 0, 0); | |
251 | ||
252 | input_dev->name = "TPS6507x Touchscreen"; | |
75259966 | 253 | input_dev->phys = tsc->phys; |
5705b8ac DT |
254 | input_dev->dev.parent = tsc->dev; |
255 | input_dev->id.bustype = BUS_I2C; | |
75259966 | 256 | if (init_data) { |
75259966 TF |
257 | input_dev->id.vendor = init_data->vendor; |
258 | input_dev->id.product = init_data->product; | |
259 | input_dev->id.version = init_data->version; | |
75259966 TF |
260 | } |
261 | ||
262 | error = tps6507x_adc_standby(tsc); | |
263 | if (error) | |
2e2a0db8 | 264 | return error; |
75259966 | 265 | |
7cca5a34 DT |
266 | error = input_setup_polling(input_dev, tps6507x_ts_poll); |
267 | if (error) | |
268 | return error; | |
269 | ||
270 | input_set_poll_interval(input_dev, | |
271 | init_data ? init_data->poll_period : | |
272 | TSC_DEFAULT_POLL_PERIOD); | |
273 | ||
274 | error = input_register_device(input_dev); | |
75259966 | 275 | if (error) |
2e2a0db8 | 276 | return error; |
75259966 TF |
277 | |
278 | return 0; | |
279 | } | |
280 | ||
281 | static struct platform_driver tps6507x_ts_driver = { | |
282 | .driver = { | |
283 | .name = "tps6507x-ts", | |
75259966 TF |
284 | }, |
285 | .probe = tps6507x_ts_probe, | |
75259966 | 286 | }; |
cdcc96e2 | 287 | module_platform_driver(tps6507x_ts_driver); |
75259966 TF |
288 | |
289 | MODULE_AUTHOR("Todd Fischer <todd.fischer@ridgerun.com>"); | |
290 | MODULE_DESCRIPTION("TPS6507x - TouchScreen driver"); | |
291 | MODULE_LICENSE("GPL v2"); | |
79026ff2 | 292 | MODULE_ALIAS("platform:tps6507x-ts"); |