1 | // SPDX-License-Identifier: GPL-2.0-only |
2 | /* |
3 | * Copyright (C) ST-Ericsson SA 2010 |
4 | * |
5 | * Author: Naveen Kumar G <naveen.gaddipati@stericsson.com> for ST-Ericsson |
6 | * Author: Sundar Iyer <sundar.iyer@stericsson.com> for ST-Ericsson |
7 | * |
8 | * Keypad controller driver for the SKE (Scroll Key Encoder) module used in |
9 | * the Nomadik 8815 and Ux500 platforms. |
10 | */ |
11 | |
12 | #include <linux/platform_device.h> |
13 | #include <linux/interrupt.h> |
14 | #include <linux/spinlock.h> |
15 | #include <linux/io.h> |
16 | #include <linux/delay.h> |
17 | #include <linux/input.h> |
18 | #include <linux/slab.h> |
19 | #include <linux/clk.h> |
20 | #include <linux/module.h> |
21 | |
22 | #include <linux/platform_data/keypad-nomadik-ske.h> |
23 | |
24 | /* SKE_CR bits */ |
25 | #define SKE_KPMLT (0x1 << 6) |
26 | #define SKE_KPCN (0x7 << 3) |
27 | #define SKE_KPASEN (0x1 << 2) |
28 | #define SKE_KPASON (0x1 << 7) |
29 | |
30 | /* SKE_IMSC bits */ |
31 | #define SKE_KPIMA (0x1 << 2) |
32 | |
33 | /* SKE_ICR bits */ |
34 | #define SKE_KPICS (0x1 << 3) |
35 | #define SKE_KPICA (0x1 << 2) |
36 | |
37 | /* SKE_RIS bits */ |
38 | #define SKE_KPRISA (0x1 << 2) |
39 | |
40 | #define SKE_KEYPAD_ROW_SHIFT 3 |
41 | #define SKE_KPD_NUM_ROWS 8 |
42 | #define SKE_KPD_NUM_COLS 8 |
43 | |
44 | /* keypad auto scan registers */ |
45 | #define SKE_ASR0 0x20 |
46 | #define SKE_ASR1 0x24 |
47 | #define SKE_ASR2 0x28 |
48 | #define SKE_ASR3 0x2C |
49 | |
50 | #define SKE_NUM_ASRX_REGISTERS (4) |
51 | #define KEY_PRESSED_DELAY 10 |
52 | |
53 | /** |
54 | * struct ske_keypad - data structure used by keypad driver |
55 | * @irq: irq no |
56 | * @reg_base: ske registers base address |
57 | * @input: pointer to input device object |
58 | * @board: keypad platform device |
59 | * @keymap: matrix scan code table for keycodes |
60 | * @clk: clock structure pointer |
61 | * @pclk: clock structure pointer |
62 | * @ske_keypad_lock: spinlock protecting the keypad read/writes |
63 | */ |
64 | struct ske_keypad { |
65 | int irq; |
66 | void __iomem *reg_base; |
67 | struct input_dev *input; |
68 | const struct ske_keypad_platform_data *board; |
69 | unsigned short keymap[SKE_KPD_NUM_ROWS * SKE_KPD_NUM_COLS]; |
70 | struct clk *clk; |
71 | struct clk *pclk; |
72 | spinlock_t ske_keypad_lock; |
73 | }; |
74 | |
75 | static void ske_keypad_set_bits(struct ske_keypad *keypad, u16 addr, |
76 | u8 mask, u8 data) |
77 | { |
78 | u32 ret; |
79 | |
80 | spin_lock(lock: &keypad->ske_keypad_lock); |
81 | |
82 | ret = readl(addr: keypad->reg_base + addr); |
83 | ret &= ~mask; |
84 | ret |= data; |
85 | writel(val: ret, addr: keypad->reg_base + addr); |
86 | |
87 | spin_unlock(lock: &keypad->ske_keypad_lock); |
88 | } |
89 | |
90 | /* |
91 | * ske_keypad_chip_init: init keypad controller configuration |
92 | * |
93 | * Enable Multi key press detection, auto scan mode |
94 | */ |
95 | static int __init ske_keypad_chip_init(struct ske_keypad *keypad) |
96 | { |
97 | u32 value; |
98 | int timeout = keypad->board->debounce_ms; |
99 | |
100 | /* check SKE_RIS to be 0 */ |
101 | while ((readl(addr: keypad->reg_base + SKE_RIS) != 0x00000000) && timeout--) |
102 | cpu_relax(); |
103 | |
104 | if (timeout == -1) |
105 | return -EINVAL; |
106 | |
107 | /* |
108 | * set debounce value |
109 | * keypad dbounce is configured in DBCR[15:8] |
110 | * dbounce value in steps of 32/32.768 ms |
111 | */ |
112 | spin_lock(lock: &keypad->ske_keypad_lock); |
113 | value = readl(addr: keypad->reg_base + SKE_DBCR); |
114 | value = value & 0xff; |
115 | value |= ((keypad->board->debounce_ms * 32000)/32768) << 8; |
116 | writel(val: value, addr: keypad->reg_base + SKE_DBCR); |
117 | spin_unlock(lock: &keypad->ske_keypad_lock); |
118 | |
119 | /* enable multi key detection */ |
120 | ske_keypad_set_bits(keypad, SKE_CR, mask: 0x0, SKE_KPMLT); |
121 | |
122 | /* |
123 | * set up the number of columns |
124 | * KPCN[5:3] defines no. of keypad columns to be auto scanned |
125 | */ |
126 | value = (keypad->board->kcol - 1) << 3; |
127 | ske_keypad_set_bits(keypad, SKE_CR, SKE_KPCN, data: value); |
128 | |
129 | /* clear keypad interrupt for auto(and pending SW) scans */ |
130 | ske_keypad_set_bits(keypad, SKE_ICR, mask: 0x0, SKE_KPICA | SKE_KPICS); |
131 | |
132 | /* un-mask keypad interrupts */ |
133 | ske_keypad_set_bits(keypad, SKE_IMSC, mask: 0x0, SKE_KPIMA); |
134 | |
135 | /* enable automatic scan */ |
136 | ske_keypad_set_bits(keypad, SKE_CR, mask: 0x0, SKE_KPASEN); |
137 | |
138 | return 0; |
139 | } |
140 | |
141 | static void ske_keypad_report(struct ske_keypad *keypad, u8 status, int col) |
142 | { |
143 | int row = 0, code, pos; |
144 | struct input_dev *input = keypad->input; |
145 | u32 ske_ris; |
146 | int key_pressed; |
147 | int num_of_rows; |
148 | |
149 | /* find out the row */ |
150 | num_of_rows = hweight8(status); |
151 | do { |
152 | pos = __ffs(status); |
153 | row = pos; |
154 | status &= ~(1 << pos); |
155 | |
156 | code = MATRIX_SCAN_CODE(row, col, SKE_KEYPAD_ROW_SHIFT); |
157 | ske_ris = readl(addr: keypad->reg_base + SKE_RIS); |
158 | key_pressed = ske_ris & SKE_KPRISA; |
159 | |
160 | input_event(dev: input, EV_MSC, MSC_SCAN, value: code); |
161 | input_report_key(dev: input, code: keypad->keymap[code], value: key_pressed); |
162 | input_sync(dev: input); |
163 | num_of_rows--; |
164 | } while (num_of_rows); |
165 | } |
166 | |
167 | static void ske_keypad_read_data(struct ske_keypad *keypad) |
168 | { |
169 | u8 status; |
170 | int col = 0; |
171 | int ske_asr, i; |
172 | |
173 | /* |
174 | * Read the auto scan registers |
175 | * |
176 | * Each SKE_ASRx (x=0 to x=3) contains two row values. |
177 | * lower byte contains row value for column 2*x, |
178 | * upper byte contains row value for column 2*x + 1 |
179 | */ |
180 | for (i = 0; i < SKE_NUM_ASRX_REGISTERS; i++) { |
181 | ske_asr = readl(addr: keypad->reg_base + SKE_ASR0 + (4 * i)); |
182 | if (!ske_asr) |
183 | continue; |
184 | |
185 | /* now that ASRx is zero, find out the coloumn x and row y */ |
186 | status = ske_asr & 0xff; |
187 | if (status) { |
188 | col = i * 2; |
189 | ske_keypad_report(keypad, status, col); |
190 | } |
191 | status = (ske_asr & 0xff00) >> 8; |
192 | if (status) { |
193 | col = (i * 2) + 1; |
194 | ske_keypad_report(keypad, status, col); |
195 | } |
196 | } |
197 | } |
198 | |
199 | static irqreturn_t ske_keypad_irq(int irq, void *dev_id) |
200 | { |
201 | struct ske_keypad *keypad = dev_id; |
202 | int timeout = keypad->board->debounce_ms; |
203 | |
204 | /* disable auto scan interrupt; mask the interrupt generated */ |
205 | ske_keypad_set_bits(keypad, SKE_IMSC, mask: ~SKE_KPIMA, data: 0x0); |
206 | ske_keypad_set_bits(keypad, SKE_ICR, mask: 0x0, SKE_KPICA); |
207 | |
208 | while ((readl(addr: keypad->reg_base + SKE_CR) & SKE_KPASON) && --timeout) |
209 | cpu_relax(); |
210 | |
211 | /* SKEx registers are stable and can be read */ |
212 | ske_keypad_read_data(keypad); |
213 | |
214 | /* wait until raw interrupt is clear */ |
215 | while ((readl(addr: keypad->reg_base + SKE_RIS)) && --timeout) |
216 | msleep(KEY_PRESSED_DELAY); |
217 | |
218 | /* enable auto scan interrupts */ |
219 | ske_keypad_set_bits(keypad, SKE_IMSC, mask: 0x0, SKE_KPIMA); |
220 | |
221 | return IRQ_HANDLED; |
222 | } |
223 | |
224 | static void ske_keypad_board_exit(void *data) |
225 | { |
226 | struct ske_keypad *keypad = data; |
227 | |
228 | keypad->board->exit(); |
229 | } |
230 | |
231 | static int __init ske_keypad_probe(struct platform_device *pdev) |
232 | { |
233 | const struct ske_keypad_platform_data *plat = |
234 | dev_get_platdata(dev: &pdev->dev); |
235 | struct device *dev = &pdev->dev; |
236 | struct ske_keypad *keypad; |
237 | struct input_dev *input; |
238 | int irq; |
239 | int error; |
240 | |
241 | if (!plat) { |
242 | dev_err(&pdev->dev, "invalid keypad platform data\n" ); |
243 | return -EINVAL; |
244 | } |
245 | |
246 | irq = platform_get_irq(pdev, 0); |
247 | if (irq < 0) |
248 | return irq; |
249 | |
250 | keypad = devm_kzalloc(dev, size: sizeof(struct ske_keypad), |
251 | GFP_KERNEL); |
252 | input = devm_input_allocate_device(dev); |
253 | if (!keypad || !input) { |
254 | dev_err(&pdev->dev, "failed to allocate keypad memory\n" ); |
255 | return -ENOMEM; |
256 | } |
257 | |
258 | keypad->irq = irq; |
259 | keypad->board = plat; |
260 | keypad->input = input; |
261 | spin_lock_init(&keypad->ske_keypad_lock); |
262 | |
263 | keypad->reg_base = devm_platform_ioremap_resource(pdev, index: 0); |
264 | if (IS_ERR(ptr: keypad->reg_base)) |
265 | return PTR_ERR(ptr: keypad->reg_base); |
266 | |
267 | keypad->pclk = devm_clk_get_enabled(dev, id: "apb_pclk" ); |
268 | if (IS_ERR(ptr: keypad->pclk)) { |
269 | dev_err(&pdev->dev, "failed to get pclk\n" ); |
270 | return PTR_ERR(ptr: keypad->pclk); |
271 | } |
272 | |
273 | keypad->clk = devm_clk_get_enabled(dev, NULL); |
274 | if (IS_ERR(ptr: keypad->clk)) { |
275 | dev_err(&pdev->dev, "failed to get clk\n" ); |
276 | return PTR_ERR(ptr: keypad->clk); |
277 | } |
278 | |
279 | input->id.bustype = BUS_HOST; |
280 | input->name = "ux500-ske-keypad" ; |
281 | input->dev.parent = &pdev->dev; |
282 | |
283 | error = matrix_keypad_build_keymap(keymap_data: plat->keymap_data, NULL, |
284 | SKE_KPD_NUM_ROWS, SKE_KPD_NUM_COLS, |
285 | keymap: keypad->keymap, input_dev: input); |
286 | if (error) { |
287 | dev_err(&pdev->dev, "Failed to build keymap\n" ); |
288 | return error; |
289 | } |
290 | |
291 | input_set_capability(dev: input, EV_MSC, MSC_SCAN); |
292 | if (!plat->no_autorepeat) |
293 | __set_bit(EV_REP, input->evbit); |
294 | |
295 | /* go through board initialization helpers */ |
296 | if (keypad->board->init) |
297 | keypad->board->init(); |
298 | |
299 | if (keypad->board->exit) { |
300 | error = devm_add_action_or_reset(dev, ske_keypad_board_exit, |
301 | keypad); |
302 | if (error) |
303 | return error; |
304 | } |
305 | |
306 | error = ske_keypad_chip_init(keypad); |
307 | if (error) { |
308 | dev_err(&pdev->dev, "unable to init keypad hardware\n" ); |
309 | return error; |
310 | } |
311 | |
312 | error = devm_request_threaded_irq(dev, irq: keypad->irq, |
313 | NULL, thread_fn: ske_keypad_irq, |
314 | IRQF_ONESHOT, devname: "ske-keypad" , dev_id: keypad); |
315 | if (error) { |
316 | dev_err(&pdev->dev, "allocate irq %d failed\n" , keypad->irq); |
317 | return error; |
318 | } |
319 | |
320 | error = input_register_device(input); |
321 | if (error) { |
322 | dev_err(&pdev->dev, |
323 | "unable to register input device: %d\n" , error); |
324 | return error; |
325 | } |
326 | |
327 | if (plat->wakeup_enable) |
328 | device_init_wakeup(dev: &pdev->dev, enable: true); |
329 | |
330 | platform_set_drvdata(pdev, data: keypad); |
331 | |
332 | return 0; |
333 | } |
334 | |
335 | static int ske_keypad_suspend(struct device *dev) |
336 | { |
337 | struct platform_device *pdev = to_platform_device(dev); |
338 | struct ske_keypad *keypad = platform_get_drvdata(pdev); |
339 | int irq = platform_get_irq(pdev, 0); |
340 | |
341 | if (device_may_wakeup(dev)) |
342 | enable_irq_wake(irq); |
343 | else |
344 | ske_keypad_set_bits(keypad, SKE_IMSC, mask: ~SKE_KPIMA, data: 0x0); |
345 | |
346 | return 0; |
347 | } |
348 | |
349 | static int ske_keypad_resume(struct device *dev) |
350 | { |
351 | struct platform_device *pdev = to_platform_device(dev); |
352 | struct ske_keypad *keypad = platform_get_drvdata(pdev); |
353 | int irq = platform_get_irq(pdev, 0); |
354 | |
355 | if (device_may_wakeup(dev)) |
356 | disable_irq_wake(irq); |
357 | else |
358 | ske_keypad_set_bits(keypad, SKE_IMSC, mask: 0x0, SKE_KPIMA); |
359 | |
360 | return 0; |
361 | } |
362 | |
363 | static DEFINE_SIMPLE_DEV_PM_OPS(ske_keypad_dev_pm_ops, |
364 | ske_keypad_suspend, ske_keypad_resume); |
365 | |
366 | static struct platform_driver ske_keypad_driver = { |
367 | .driver = { |
368 | .name = "nmk-ske-keypad" , |
369 | .pm = pm_sleep_ptr(&ske_keypad_dev_pm_ops), |
370 | }, |
371 | }; |
372 | |
373 | module_platform_driver_probe(ske_keypad_driver, ske_keypad_probe); |
374 | |
375 | MODULE_LICENSE("GPL v2" ); |
376 | MODULE_AUTHOR("Naveen Kumar <naveen.gaddipati@stericsson.com> / Sundar Iyer <sundar.iyer@stericsson.com>" ); |
377 | MODULE_DESCRIPTION("Nomadik Scroll-Key-Encoder Keypad Driver" ); |
378 | MODULE_ALIAS("platform:nomadik-ske-keypad" ); |
379 | |