1 | // SPDX-License-Identifier: GPL-2.0-or-later |
2 | /* |
3 | * TSI driver for Dialog DA9052 |
4 | * |
5 | * Copyright(c) 2012 Dialog Semiconductor Ltd. |
6 | * |
7 | * Author: David Dajun Chen <dchen@diasemi.com> |
8 | */ |
9 | #include <linux/module.h> |
10 | #include <linux/input.h> |
11 | #include <linux/delay.h> |
12 | #include <linux/platform_device.h> |
13 | #include <linux/interrupt.h> |
14 | |
15 | #include <linux/mfd/da9052/reg.h> |
16 | #include <linux/mfd/da9052/da9052.h> |
17 | |
18 | #define TSI_PEN_DOWN_STATUS 0x40 |
19 | |
20 | struct da9052_tsi { |
21 | struct da9052 *da9052; |
22 | struct input_dev *dev; |
23 | struct delayed_work ts_pen_work; |
24 | bool stopped; |
25 | bool adc_on; |
26 | }; |
27 | |
28 | static void da9052_ts_adc_toggle(struct da9052_tsi *tsi, bool on) |
29 | { |
30 | da9052_reg_update(da9052: tsi->da9052, DA9052_TSI_CONT_A_REG, bit_mask: 1 << 0, reg_val: on); |
31 | tsi->adc_on = on; |
32 | } |
33 | |
34 | static irqreturn_t da9052_ts_pendwn_irq(int irq, void *data) |
35 | { |
36 | struct da9052_tsi *tsi = data; |
37 | |
38 | if (!tsi->stopped) { |
39 | /* Mask PEN_DOWN event and unmask TSI_READY event */ |
40 | da9052_disable_irq_nosync(da9052: tsi->da9052, DA9052_IRQ_PENDOWN); |
41 | da9052_enable_irq(da9052: tsi->da9052, DA9052_IRQ_TSIREADY); |
42 | |
43 | da9052_ts_adc_toggle(tsi, on: true); |
44 | |
45 | schedule_delayed_work(dwork: &tsi->ts_pen_work, HZ / 50); |
46 | } |
47 | |
48 | return IRQ_HANDLED; |
49 | } |
50 | |
51 | static void da9052_ts_read(struct da9052_tsi *tsi) |
52 | { |
53 | struct input_dev *input = tsi->dev; |
54 | int ret; |
55 | u16 x, y, z; |
56 | u8 v; |
57 | |
58 | ret = da9052_reg_read(da9052: tsi->da9052, DA9052_TSI_X_MSB_REG); |
59 | if (ret < 0) |
60 | return; |
61 | |
62 | x = (u16) ret; |
63 | |
64 | ret = da9052_reg_read(da9052: tsi->da9052, DA9052_TSI_Y_MSB_REG); |
65 | if (ret < 0) |
66 | return; |
67 | |
68 | y = (u16) ret; |
69 | |
70 | ret = da9052_reg_read(da9052: tsi->da9052, DA9052_TSI_Z_MSB_REG); |
71 | if (ret < 0) |
72 | return; |
73 | |
74 | z = (u16) ret; |
75 | |
76 | ret = da9052_reg_read(da9052: tsi->da9052, DA9052_TSI_LSB_REG); |
77 | if (ret < 0) |
78 | return; |
79 | |
80 | v = (u8) ret; |
81 | |
82 | x = ((x << 2) & 0x3fc) | (v & 0x3); |
83 | y = ((y << 2) & 0x3fc) | ((v & 0xc) >> 2); |
84 | z = ((z << 2) & 0x3fc) | ((v & 0x30) >> 4); |
85 | |
86 | input_report_key(dev: input, BTN_TOUCH, value: 1); |
87 | input_report_abs(dev: input, ABS_X, value: x); |
88 | input_report_abs(dev: input, ABS_Y, value: y); |
89 | input_report_abs(dev: input, ABS_PRESSURE, value: z); |
90 | input_sync(dev: input); |
91 | } |
92 | |
93 | static irqreturn_t da9052_ts_datardy_irq(int irq, void *data) |
94 | { |
95 | struct da9052_tsi *tsi = data; |
96 | |
97 | da9052_ts_read(tsi); |
98 | |
99 | return IRQ_HANDLED; |
100 | } |
101 | |
102 | static void da9052_ts_pen_work(struct work_struct *work) |
103 | { |
104 | struct da9052_tsi *tsi = container_of(work, struct da9052_tsi, |
105 | ts_pen_work.work); |
106 | if (!tsi->stopped) { |
107 | int ret = da9052_reg_read(da9052: tsi->da9052, DA9052_TSI_LSB_REG); |
108 | if (ret < 0 || (ret & TSI_PEN_DOWN_STATUS)) { |
109 | /* Pen is still DOWN (or read error) */ |
110 | schedule_delayed_work(dwork: &tsi->ts_pen_work, HZ / 50); |
111 | } else { |
112 | struct input_dev *input = tsi->dev; |
113 | |
114 | /* Pen UP */ |
115 | da9052_ts_adc_toggle(tsi, on: false); |
116 | |
117 | /* Report Pen UP */ |
118 | input_report_key(dev: input, BTN_TOUCH, value: 0); |
119 | input_report_abs(dev: input, ABS_PRESSURE, value: 0); |
120 | input_sync(dev: input); |
121 | |
122 | /* |
123 | * FIXME: Fixes the unhandled irq issue when quick |
124 | * pen down and pen up events occurs |
125 | */ |
126 | ret = da9052_reg_update(da9052: tsi->da9052, |
127 | DA9052_EVENT_B_REG, bit_mask: 0xC0, reg_val: 0xC0); |
128 | if (ret < 0) |
129 | return; |
130 | |
131 | /* Mask TSI_READY event and unmask PEN_DOWN event */ |
132 | da9052_disable_irq(da9052: tsi->da9052, DA9052_IRQ_TSIREADY); |
133 | da9052_enable_irq(da9052: tsi->da9052, DA9052_IRQ_PENDOWN); |
134 | } |
135 | } |
136 | } |
137 | |
138 | static int da9052_ts_configure_gpio(struct da9052 *da9052) |
139 | { |
140 | int error; |
141 | |
142 | error = da9052_reg_update(da9052, DA9052_GPIO_2_3_REG, bit_mask: 0x30, reg_val: 0); |
143 | if (error < 0) |
144 | return error; |
145 | |
146 | error = da9052_reg_update(da9052, DA9052_GPIO_4_5_REG, bit_mask: 0x33, reg_val: 0); |
147 | if (error < 0) |
148 | return error; |
149 | |
150 | error = da9052_reg_update(da9052, DA9052_GPIO_6_7_REG, bit_mask: 0x33, reg_val: 0); |
151 | if (error < 0) |
152 | return error; |
153 | |
154 | return 0; |
155 | } |
156 | |
157 | static int da9052_configure_tsi(struct da9052_tsi *tsi) |
158 | { |
159 | int error; |
160 | |
161 | error = da9052_ts_configure_gpio(da9052: tsi->da9052); |
162 | if (error) |
163 | return error; |
164 | |
165 | /* Measure TSI sample every 1ms */ |
166 | error = da9052_reg_update(da9052: tsi->da9052, DA9052_ADC_CONT_REG, |
167 | bit_mask: 1 << 6, reg_val: 1 << 6); |
168 | if (error < 0) |
169 | return error; |
170 | |
171 | /* TSI_DELAY: 3 slots, TSI_SKIP: 0 slots, TSI_MODE: XYZP */ |
172 | error = da9052_reg_update(da9052: tsi->da9052, DA9052_TSI_CONT_A_REG, bit_mask: 0xFC, reg_val: 0xC0); |
173 | if (error < 0) |
174 | return error; |
175 | |
176 | /* Supply TSIRef through LD09 */ |
177 | error = da9052_reg_write(da9052: tsi->da9052, DA9052_LDO9_REG, val: 0x59); |
178 | if (error < 0) |
179 | return error; |
180 | |
181 | return 0; |
182 | } |
183 | |
184 | static int da9052_ts_input_open(struct input_dev *input_dev) |
185 | { |
186 | struct da9052_tsi *tsi = input_get_drvdata(dev: input_dev); |
187 | |
188 | tsi->stopped = false; |
189 | mb(); |
190 | |
191 | /* Unmask PEN_DOWN event */ |
192 | da9052_enable_irq(da9052: tsi->da9052, DA9052_IRQ_PENDOWN); |
193 | |
194 | /* Enable Pen Detect Circuit */ |
195 | return da9052_reg_update(da9052: tsi->da9052, DA9052_TSI_CONT_A_REG, |
196 | bit_mask: 1 << 1, reg_val: 1 << 1); |
197 | } |
198 | |
199 | static void da9052_ts_input_close(struct input_dev *input_dev) |
200 | { |
201 | struct da9052_tsi *tsi = input_get_drvdata(dev: input_dev); |
202 | |
203 | tsi->stopped = true; |
204 | mb(); |
205 | da9052_disable_irq(da9052: tsi->da9052, DA9052_IRQ_PENDOWN); |
206 | cancel_delayed_work_sync(dwork: &tsi->ts_pen_work); |
207 | |
208 | if (tsi->adc_on) { |
209 | da9052_disable_irq(da9052: tsi->da9052, DA9052_IRQ_TSIREADY); |
210 | da9052_ts_adc_toggle(tsi, on: false); |
211 | |
212 | /* |
213 | * If ADC was on that means that pendwn IRQ was disabled |
214 | * twice and we need to enable it to keep enable/disable |
215 | * counter balanced. IRQ is still off though. |
216 | */ |
217 | da9052_enable_irq(da9052: tsi->da9052, DA9052_IRQ_PENDOWN); |
218 | } |
219 | |
220 | /* Disable Pen Detect Circuit */ |
221 | da9052_reg_update(da9052: tsi->da9052, DA9052_TSI_CONT_A_REG, bit_mask: 1 << 1, reg_val: 0); |
222 | } |
223 | |
224 | static int da9052_ts_probe(struct platform_device *pdev) |
225 | { |
226 | struct da9052 *da9052; |
227 | struct da9052_tsi *tsi; |
228 | struct input_dev *input_dev; |
229 | int error; |
230 | |
231 | da9052 = dev_get_drvdata(dev: pdev->dev.parent); |
232 | if (!da9052) |
233 | return -EINVAL; |
234 | |
235 | tsi = kzalloc(size: sizeof(struct da9052_tsi), GFP_KERNEL); |
236 | input_dev = input_allocate_device(); |
237 | if (!tsi || !input_dev) { |
238 | error = -ENOMEM; |
239 | goto err_free_mem; |
240 | } |
241 | |
242 | tsi->da9052 = da9052; |
243 | tsi->dev = input_dev; |
244 | tsi->stopped = true; |
245 | INIT_DELAYED_WORK(&tsi->ts_pen_work, da9052_ts_pen_work); |
246 | |
247 | input_dev->id.version = 0x0101; |
248 | input_dev->id.vendor = 0x15B6; |
249 | input_dev->id.product = 0x9052; |
250 | input_dev->name = "Dialog DA9052 TouchScreen Driver" ; |
251 | input_dev->dev.parent = &pdev->dev; |
252 | input_dev->open = da9052_ts_input_open; |
253 | input_dev->close = da9052_ts_input_close; |
254 | |
255 | __set_bit(EV_ABS, input_dev->evbit); |
256 | __set_bit(EV_KEY, input_dev->evbit); |
257 | __set_bit(BTN_TOUCH, input_dev->keybit); |
258 | |
259 | input_set_abs_params(dev: input_dev, ABS_X, min: 0, max: 1023, fuzz: 0, flat: 0); |
260 | input_set_abs_params(dev: input_dev, ABS_Y, min: 0, max: 1023, fuzz: 0, flat: 0); |
261 | input_set_abs_params(dev: input_dev, ABS_PRESSURE, min: 0, max: 1023, fuzz: 0, flat: 0); |
262 | |
263 | input_set_drvdata(dev: input_dev, data: tsi); |
264 | |
265 | /* Disable Pen Detect Circuit */ |
266 | da9052_reg_update(da9052: tsi->da9052, DA9052_TSI_CONT_A_REG, bit_mask: 1 << 1, reg_val: 0); |
267 | |
268 | /* Disable ADC */ |
269 | da9052_ts_adc_toggle(tsi, on: false); |
270 | |
271 | error = da9052_request_irq(da9052: tsi->da9052, DA9052_IRQ_PENDOWN, |
272 | name: "pendown-irq" , handler: da9052_ts_pendwn_irq, data: tsi); |
273 | if (error) { |
274 | dev_err(tsi->da9052->dev, |
275 | "Failed to register PENDWN IRQ: %d\n" , error); |
276 | goto err_free_mem; |
277 | } |
278 | |
279 | error = da9052_request_irq(da9052: tsi->da9052, DA9052_IRQ_TSIREADY, |
280 | name: "tsiready-irq" , handler: da9052_ts_datardy_irq, data: tsi); |
281 | if (error) { |
282 | dev_err(tsi->da9052->dev, |
283 | "Failed to register TSIRDY IRQ :%d\n" , error); |
284 | goto err_free_pendwn_irq; |
285 | } |
286 | |
287 | /* Mask PEN_DOWN and TSI_READY events */ |
288 | da9052_disable_irq(da9052: tsi->da9052, DA9052_IRQ_PENDOWN); |
289 | da9052_disable_irq(da9052: tsi->da9052, DA9052_IRQ_TSIREADY); |
290 | |
291 | error = da9052_configure_tsi(tsi); |
292 | if (error) |
293 | goto err_free_datardy_irq; |
294 | |
295 | error = input_register_device(tsi->dev); |
296 | if (error) |
297 | goto err_free_datardy_irq; |
298 | |
299 | platform_set_drvdata(pdev, data: tsi); |
300 | |
301 | return 0; |
302 | |
303 | err_free_datardy_irq: |
304 | da9052_free_irq(da9052: tsi->da9052, DA9052_IRQ_TSIREADY, data: tsi); |
305 | err_free_pendwn_irq: |
306 | da9052_free_irq(da9052: tsi->da9052, DA9052_IRQ_PENDOWN, data: tsi); |
307 | err_free_mem: |
308 | kfree(objp: tsi); |
309 | input_free_device(dev: input_dev); |
310 | |
311 | return error; |
312 | } |
313 | |
314 | static int da9052_ts_remove(struct platform_device *pdev) |
315 | { |
316 | struct da9052_tsi *tsi = platform_get_drvdata(pdev); |
317 | |
318 | da9052_reg_write(da9052: tsi->da9052, DA9052_LDO9_REG, val: 0x19); |
319 | |
320 | da9052_free_irq(da9052: tsi->da9052, DA9052_IRQ_TSIREADY, data: tsi); |
321 | da9052_free_irq(da9052: tsi->da9052, DA9052_IRQ_PENDOWN, data: tsi); |
322 | |
323 | input_unregister_device(tsi->dev); |
324 | kfree(objp: tsi); |
325 | |
326 | return 0; |
327 | } |
328 | |
329 | static struct platform_driver da9052_tsi_driver = { |
330 | .probe = da9052_ts_probe, |
331 | .remove = da9052_ts_remove, |
332 | .driver = { |
333 | .name = "da9052-tsi" , |
334 | }, |
335 | }; |
336 | |
337 | module_platform_driver(da9052_tsi_driver); |
338 | |
339 | MODULE_DESCRIPTION("Touchscreen driver for Dialog Semiconductor DA9052" ); |
340 | MODULE_AUTHOR("Anthony Olech <Anthony.Olech@diasemi.com>" ); |
341 | MODULE_LICENSE("GPL" ); |
342 | MODULE_ALIAS("platform:da9052-tsi" ); |
343 | |