tjh.dev
Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
1/*
2 * SPEAr Keyboard Driver
3 * Based on omap-keypad driver
4 *
5 * Copyright (C) 2010 ST Microelectronics
6 * Rajeev Kumar<rajeev-dlh.kumar@st.com>
7 *
8 * This file is licensed under the terms of the GNU General Public
9 * License version 2. This program is licensed "as is" without any
10 * warranty of any kind, whether express or implied.
11 */
12
13#include <linux/clk.h>
14#include <linux/errno.h>
15#include <linux/init.h>
16#include <linux/interrupt.h>
17#include <linux/input.h>
18#include <linux/io.h>
19#include <linux/irq.h>
20#include <linux/kernel.h>
21#include <linux/module.h>
22#include <linux/of.h>
23#include <linux/platform_device.h>
24#include <linux/pm_wakeup.h>
25#include <linux/slab.h>
26#include <linux/types.h>
27#include <linux/platform_data/keyboard-spear.h>
28
29/* Keyboard Registers */
30#define MODE_CTL_REG 0x00
31#define STATUS_REG 0x0C
32#define DATA_REG 0x10
33#define INTR_MASK 0x54
34
35/* Register Values */
36#define NUM_ROWS 16
37#define NUM_COLS 16
38#define MODE_CTL_PCLK_FREQ_SHIFT 9
39#define MODE_CTL_PCLK_FREQ_MSK 0x7F
40
41#define MODE_CTL_KEYBOARD (0x2 << 0)
42#define MODE_CTL_SCAN_RATE_10 (0x0 << 2)
43#define MODE_CTL_SCAN_RATE_20 (0x1 << 2)
44#define MODE_CTL_SCAN_RATE_40 (0x2 << 2)
45#define MODE_CTL_SCAN_RATE_80 (0x3 << 2)
46#define MODE_CTL_KEYNUM_SHIFT 6
47#define MODE_CTL_START_SCAN (0x1 << 8)
48
49#define STATUS_DATA_AVAIL (0x1 << 1)
50
51#define DATA_ROW_MASK 0xF0
52#define DATA_COLUMN_MASK 0x0F
53
54#define ROW_SHIFT 4
55
56struct spear_kbd {
57 struct input_dev *input;
58 void __iomem *io_base;
59 struct clk *clk;
60 unsigned int irq;
61 unsigned int mode;
62 unsigned int suspended_rate;
63 unsigned short last_key;
64 unsigned short keycodes[NUM_ROWS * NUM_COLS];
65 bool rep;
66 bool irq_wake_enabled;
67 u32 mode_ctl_reg;
68};
69
70static irqreturn_t spear_kbd_interrupt(int irq, void *dev_id)
71{
72 struct spear_kbd *kbd = dev_id;
73 struct input_dev *input = kbd->input;
74 unsigned int key;
75 u32 sts, val;
76
77 sts = readl_relaxed(kbd->io_base + STATUS_REG);
78 if (!(sts & STATUS_DATA_AVAIL))
79 return IRQ_NONE;
80
81 if (kbd->last_key != KEY_RESERVED) {
82 input_report_key(input, kbd->last_key, 0);
83 kbd->last_key = KEY_RESERVED;
84 }
85
86 /* following reads active (row, col) pair */
87 val = readl_relaxed(kbd->io_base + DATA_REG) &
88 (DATA_ROW_MASK | DATA_COLUMN_MASK);
89 key = kbd->keycodes[val];
90
91 input_event(input, EV_MSC, MSC_SCAN, val);
92 input_report_key(input, key, 1);
93 input_sync(input);
94
95 kbd->last_key = key;
96
97 /* clear interrupt */
98 writel_relaxed(0, kbd->io_base + STATUS_REG);
99
100 return IRQ_HANDLED;
101}
102
103static int spear_kbd_open(struct input_dev *dev)
104{
105 struct spear_kbd *kbd = input_get_drvdata(dev);
106 int error;
107 u32 val;
108
109 kbd->last_key = KEY_RESERVED;
110
111 error = clk_enable(kbd->clk);
112 if (error)
113 return error;
114
115 /* keyboard rate to be programmed is input clock (in MHz) - 1 */
116 val = clk_get_rate(kbd->clk) / 1000000 - 1;
117 val = (val & MODE_CTL_PCLK_FREQ_MSK) << MODE_CTL_PCLK_FREQ_SHIFT;
118
119 /* program keyboard */
120 val = MODE_CTL_SCAN_RATE_80 | MODE_CTL_KEYBOARD | val |
121 (kbd->mode << MODE_CTL_KEYNUM_SHIFT);
122 writel_relaxed(val, kbd->io_base + MODE_CTL_REG);
123 writel_relaxed(1, kbd->io_base + STATUS_REG);
124
125 /* start key scan */
126 val = readl_relaxed(kbd->io_base + MODE_CTL_REG);
127 val |= MODE_CTL_START_SCAN;
128 writel_relaxed(val, kbd->io_base + MODE_CTL_REG);
129
130 return 0;
131}
132
133static void spear_kbd_close(struct input_dev *dev)
134{
135 struct spear_kbd *kbd = input_get_drvdata(dev);
136 u32 val;
137
138 /* stop key scan */
139 val = readl_relaxed(kbd->io_base + MODE_CTL_REG);
140 val &= ~MODE_CTL_START_SCAN;
141 writel_relaxed(val, kbd->io_base + MODE_CTL_REG);
142
143 clk_disable(kbd->clk);
144
145 kbd->last_key = KEY_RESERVED;
146}
147
148#ifdef CONFIG_OF
149static int spear_kbd_parse_dt(struct platform_device *pdev,
150 struct spear_kbd *kbd)
151{
152 struct device_node *np = pdev->dev.of_node;
153 int error;
154 u32 val, suspended_rate;
155
156 if (!np) {
157 dev_err(&pdev->dev, "Missing DT data\n");
158 return -EINVAL;
159 }
160
161 if (of_property_read_bool(np, "autorepeat"))
162 kbd->rep = true;
163
164 if (of_property_read_u32(np, "suspended_rate", &suspended_rate))
165 kbd->suspended_rate = suspended_rate;
166
167 error = of_property_read_u32(np, "st,mode", &val);
168 if (error) {
169 dev_err(&pdev->dev, "DT: Invalid or missing mode\n");
170 return error;
171 }
172
173 kbd->mode = val;
174 return 0;
175}
176#else
177static inline int spear_kbd_parse_dt(struct platform_device *pdev,
178 struct spear_kbd *kbd)
179{
180 return -ENOSYS;
181}
182#endif
183
184static int spear_kbd_probe(struct platform_device *pdev)
185{
186 struct kbd_platform_data *pdata = dev_get_platdata(&pdev->dev);
187 const struct matrix_keymap_data *keymap = pdata ? pdata->keymap : NULL;
188 struct spear_kbd *kbd;
189 struct input_dev *input_dev;
190 struct resource *res;
191 int irq;
192 int error;
193
194 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
195 if (!res) {
196 dev_err(&pdev->dev, "no keyboard resource defined\n");
197 return -EBUSY;
198 }
199
200 irq = platform_get_irq(pdev, 0);
201 if (irq < 0) {
202 dev_err(&pdev->dev, "not able to get irq for the device\n");
203 return irq;
204 }
205
206 kbd = devm_kzalloc(&pdev->dev, sizeof(*kbd), GFP_KERNEL);
207 if (!kbd) {
208 dev_err(&pdev->dev, "not enough memory for driver data\n");
209 return -ENOMEM;
210 }
211
212 input_dev = devm_input_allocate_device(&pdev->dev);
213 if (!input_dev) {
214 dev_err(&pdev->dev, "unable to allocate input device\n");
215 return -ENOMEM;
216 }
217
218 kbd->input = input_dev;
219 kbd->irq = irq;
220
221 if (!pdata) {
222 error = spear_kbd_parse_dt(pdev, kbd);
223 if (error)
224 return error;
225 } else {
226 kbd->mode = pdata->mode;
227 kbd->rep = pdata->rep;
228 kbd->suspended_rate = pdata->suspended_rate;
229 }
230
231 kbd->io_base = devm_request_and_ioremap(&pdev->dev, res);
232 if (!kbd->io_base) {
233 dev_err(&pdev->dev, "request-ioremap failed for kbd_region\n");
234 return -ENOMEM;
235 }
236
237 kbd->clk = devm_clk_get(&pdev->dev, NULL);
238 if (IS_ERR(kbd->clk))
239 return PTR_ERR(kbd->clk);
240
241 input_dev->name = "Spear Keyboard";
242 input_dev->phys = "keyboard/input0";
243 input_dev->id.bustype = BUS_HOST;
244 input_dev->id.vendor = 0x0001;
245 input_dev->id.product = 0x0001;
246 input_dev->id.version = 0x0100;
247 input_dev->open = spear_kbd_open;
248 input_dev->close = spear_kbd_close;
249
250 error = matrix_keypad_build_keymap(keymap, NULL, NUM_ROWS, NUM_COLS,
251 kbd->keycodes, input_dev);
252 if (error) {
253 dev_err(&pdev->dev, "Failed to build keymap\n");
254 return error;
255 }
256
257 if (kbd->rep)
258 __set_bit(EV_REP, input_dev->evbit);
259 input_set_capability(input_dev, EV_MSC, MSC_SCAN);
260
261 input_set_drvdata(input_dev, kbd);
262
263 error = devm_request_irq(&pdev->dev, irq, spear_kbd_interrupt, 0,
264 "keyboard", kbd);
265 if (error) {
266 dev_err(&pdev->dev, "request_irq failed\n");
267 return error;
268 }
269
270 error = clk_prepare(kbd->clk);
271 if (error)
272 return error;
273
274 error = input_register_device(input_dev);
275 if (error) {
276 dev_err(&pdev->dev, "Unable to register keyboard device\n");
277 clk_unprepare(kbd->clk);
278 return error;
279 }
280
281 device_init_wakeup(&pdev->dev, 1);
282 platform_set_drvdata(pdev, kbd);
283
284 return 0;
285}
286
287static int spear_kbd_remove(struct platform_device *pdev)
288{
289 struct spear_kbd *kbd = platform_get_drvdata(pdev);
290
291 input_unregister_device(kbd->input);
292 clk_unprepare(kbd->clk);
293
294 device_init_wakeup(&pdev->dev, 0);
295 platform_set_drvdata(pdev, NULL);
296
297 return 0;
298}
299
300#ifdef CONFIG_PM
301static int spear_kbd_suspend(struct device *dev)
302{
303 struct platform_device *pdev = to_platform_device(dev);
304 struct spear_kbd *kbd = platform_get_drvdata(pdev);
305 struct input_dev *input_dev = kbd->input;
306 unsigned int rate = 0, mode_ctl_reg, val;
307
308 mutex_lock(&input_dev->mutex);
309
310 /* explicitly enable clock as we may program device */
311 clk_enable(kbd->clk);
312
313 mode_ctl_reg = readl_relaxed(kbd->io_base + MODE_CTL_REG);
314
315 if (device_may_wakeup(&pdev->dev)) {
316 if (!enable_irq_wake(kbd->irq))
317 kbd->irq_wake_enabled = true;
318
319 /*
320 * reprogram the keyboard operating frequency as on some
321 * platform it may change during system suspended
322 */
323 if (kbd->suspended_rate)
324 rate = kbd->suspended_rate / 1000000 - 1;
325 else
326 rate = clk_get_rate(kbd->clk) / 1000000 - 1;
327
328 val = mode_ctl_reg &
329 ~(MODE_CTL_PCLK_FREQ_MSK << MODE_CTL_PCLK_FREQ_SHIFT);
330 val |= (rate & MODE_CTL_PCLK_FREQ_MSK)
331 << MODE_CTL_PCLK_FREQ_SHIFT;
332 writel_relaxed(val, kbd->io_base + MODE_CTL_REG);
333
334 } else {
335 if (input_dev->users) {
336 writel_relaxed(mode_ctl_reg & ~MODE_CTL_START_SCAN,
337 kbd->io_base + MODE_CTL_REG);
338 clk_disable(kbd->clk);
339 }
340 }
341
342 /* store current configuration */
343 if (input_dev->users)
344 kbd->mode_ctl_reg = mode_ctl_reg;
345
346 /* restore previous clk state */
347 clk_disable(kbd->clk);
348
349 mutex_unlock(&input_dev->mutex);
350
351 return 0;
352}
353
354static int spear_kbd_resume(struct device *dev)
355{
356 struct platform_device *pdev = to_platform_device(dev);
357 struct spear_kbd *kbd = platform_get_drvdata(pdev);
358 struct input_dev *input_dev = kbd->input;
359
360 mutex_lock(&input_dev->mutex);
361
362 if (device_may_wakeup(&pdev->dev)) {
363 if (kbd->irq_wake_enabled) {
364 kbd->irq_wake_enabled = false;
365 disable_irq_wake(kbd->irq);
366 }
367 } else {
368 if (input_dev->users)
369 clk_enable(kbd->clk);
370 }
371
372 /* restore current configuration */
373 if (input_dev->users)
374 writel_relaxed(kbd->mode_ctl_reg, kbd->io_base + MODE_CTL_REG);
375
376 mutex_unlock(&input_dev->mutex);
377
378 return 0;
379}
380#endif
381
382static SIMPLE_DEV_PM_OPS(spear_kbd_pm_ops, spear_kbd_suspend, spear_kbd_resume);
383
384#ifdef CONFIG_OF
385static const struct of_device_id spear_kbd_id_table[] = {
386 { .compatible = "st,spear300-kbd" },
387 {}
388};
389MODULE_DEVICE_TABLE(of, spear_kbd_id_table);
390#endif
391
392static struct platform_driver spear_kbd_driver = {
393 .probe = spear_kbd_probe,
394 .remove = spear_kbd_remove,
395 .driver = {
396 .name = "keyboard",
397 .owner = THIS_MODULE,
398 .pm = &spear_kbd_pm_ops,
399 .of_match_table = of_match_ptr(spear_kbd_id_table),
400 },
401};
402module_platform_driver(spear_kbd_driver);
403
404MODULE_AUTHOR("Rajeev Kumar");
405MODULE_DESCRIPTION("SPEAr Keyboard Driver");
406MODULE_LICENSE("GPL");