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15#include <linux/module.h>
16#include <linux/interrupt.h>
17#include <linux/slab.h>
18#include <linux/irq.h>
19#include <linux/pm.h>
20#include <linux/platform_device.h>
21#include <linux/input.h>
22#include <linux/clk.h>
23#include <linux/io.h>
24#include <linux/of.h>
25#include <linux/input/matrix_keypad.h>
26
27#define DRV_NAME "lpc32xx_keys"
28
29
30
31
32#define LPC32XX_KS_DEB(x) ((x) + 0x00)
33#define LPC32XX_KS_STATE_COND(x) ((x) + 0x04)
34#define LPC32XX_KS_IRQ(x) ((x) + 0x08)
35#define LPC32XX_KS_SCAN_CTL(x) ((x) + 0x0C)
36#define LPC32XX_KS_FAST_TST(x) ((x) + 0x10)
37#define LPC32XX_KS_MATRIX_DIM(x) ((x) + 0x14)
38#define LPC32XX_KS_DATA(x, y) ((x) + 0x40 + ((y) << 2))
39
40#define LPC32XX_KSCAN_DEB_NUM_DEB_PASS(n) ((n) & 0xFF)
41
42#define LPC32XX_KSCAN_SCOND_IN_IDLE 0x0
43#define LPC32XX_KSCAN_SCOND_IN_SCANONCE 0x1
44#define LPC32XX_KSCAN_SCOND_IN_IRQGEN 0x2
45#define LPC32XX_KSCAN_SCOND_IN_SCAN_MATRIX 0x3
46
47#define LPC32XX_KSCAN_IRQ_PENDING_CLR 0x1
48
49#define LPC32XX_KSCAN_SCTRL_SCAN_DELAY(n) ((n) & 0xFF)
50
51#define LPC32XX_KSCAN_FTST_FORCESCANONCE 0x1
52#define LPC32XX_KSCAN_FTST_USE32K_CLK 0x2
53
54#define LPC32XX_KSCAN_MSEL_SELECT(n) ((n) & 0xF)
55
56struct lpc32xx_kscan_drv {
57 struct input_dev *input;
58 struct clk *clk;
59 void __iomem *kscan_base;
60 unsigned int irq;
61
62 u32 matrix_sz;
63 u32 deb_clks;
64 u32 scan_delay;
65
66 unsigned short *keymap;
67 unsigned int row_shift;
68
69 u8 lastkeystates[8];
70};
71
72static void lpc32xx_mod_states(struct lpc32xx_kscan_drv *kscandat, int col)
73{
74 struct input_dev *input = kscandat->input;
75 unsigned row, changed, scancode, keycode;
76 u8 key;
77
78 key = readl(LPC32XX_KS_DATA(kscandat->kscan_base, col));
79 changed = key ^ kscandat->lastkeystates[col];
80 kscandat->lastkeystates[col] = key;
81
82 for (row = 0; changed; row++, changed >>= 1) {
83 if (changed & 1) {
84
85 scancode = MATRIX_SCAN_CODE(row, col,
86 kscandat->row_shift);
87 keycode = kscandat->keymap[scancode];
88 input_event(input, EV_MSC, MSC_SCAN, scancode);
89 input_report_key(input, keycode, key & (1 << row));
90 }
91 }
92}
93
94static irqreturn_t lpc32xx_kscan_irq(int irq, void *dev_id)
95{
96 struct lpc32xx_kscan_drv *kscandat = dev_id;
97 int i;
98
99 for (i = 0; i < kscandat->matrix_sz; i++)
100 lpc32xx_mod_states(kscandat, i);
101
102 writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
103
104 input_sync(kscandat->input);
105
106 return IRQ_HANDLED;
107}
108
109static int lpc32xx_kscan_open(struct input_dev *dev)
110{
111 struct lpc32xx_kscan_drv *kscandat = input_get_drvdata(dev);
112 int error;
113
114 error = clk_prepare_enable(kscandat->clk);
115 if (error)
116 return error;
117
118 writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
119
120 return 0;
121}
122
123static void lpc32xx_kscan_close(struct input_dev *dev)
124{
125 struct lpc32xx_kscan_drv *kscandat = input_get_drvdata(dev);
126
127 writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
128 clk_disable_unprepare(kscandat->clk);
129}
130
131static int lpc32xx_parse_dt(struct device *dev,
132 struct lpc32xx_kscan_drv *kscandat)
133{
134 struct device_node *np = dev->of_node;
135 u32 rows = 0, columns = 0;
136 int err;
137
138 err = matrix_keypad_parse_properties(dev, &rows, &columns);
139 if (err)
140 return err;
141 if (rows != columns) {
142 dev_err(dev, "rows and columns must be equal!\n");
143 return -EINVAL;
144 }
145
146 kscandat->matrix_sz = rows;
147 kscandat->row_shift = get_count_order(columns);
148
149 of_property_read_u32(np, "nxp,debounce-delay-ms", &kscandat->deb_clks);
150 of_property_read_u32(np, "nxp,scan-delay-ms", &kscandat->scan_delay);
151 if (!kscandat->deb_clks || !kscandat->scan_delay) {
152 dev_err(dev, "debounce or scan delay not specified\n");
153 return -EINVAL;
154 }
155
156 return 0;
157}
158
159static int lpc32xx_kscan_probe(struct platform_device *pdev)
160{
161 struct lpc32xx_kscan_drv *kscandat;
162 struct input_dev *input;
163 struct resource *res;
164 size_t keymap_size;
165 int error;
166 int irq;
167
168 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
169 if (!res) {
170 dev_err(&pdev->dev, "failed to get platform I/O memory\n");
171 return -EINVAL;
172 }
173
174 irq = platform_get_irq(pdev, 0);
175 if (irq < 0)
176 return -EINVAL;
177
178 kscandat = devm_kzalloc(&pdev->dev, sizeof(*kscandat),
179 GFP_KERNEL);
180 if (!kscandat)
181 return -ENOMEM;
182
183 error = lpc32xx_parse_dt(&pdev->dev, kscandat);
184 if (error) {
185 dev_err(&pdev->dev, "failed to parse device tree\n");
186 return error;
187 }
188
189 keymap_size = sizeof(kscandat->keymap[0]) *
190 (kscandat->matrix_sz << kscandat->row_shift);
191 kscandat->keymap = devm_kzalloc(&pdev->dev, keymap_size, GFP_KERNEL);
192 if (!kscandat->keymap)
193 return -ENOMEM;
194
195 kscandat->input = input = devm_input_allocate_device(&pdev->dev);
196 if (!input) {
197 dev_err(&pdev->dev, "failed to allocate input device\n");
198 return -ENOMEM;
199 }
200
201
202 input->name = pdev->name;
203 input->phys = "lpc32xx/input0";
204 input->id.vendor = 0x0001;
205 input->id.product = 0x0001;
206 input->id.version = 0x0100;
207 input->open = lpc32xx_kscan_open;
208 input->close = lpc32xx_kscan_close;
209 input->dev.parent = &pdev->dev;
210
211 input_set_capability(input, EV_MSC, MSC_SCAN);
212
213 error = matrix_keypad_build_keymap(NULL, NULL,
214 kscandat->matrix_sz,
215 kscandat->matrix_sz,
216 kscandat->keymap, kscandat->input);
217 if (error) {
218 dev_err(&pdev->dev, "failed to build keymap\n");
219 return error;
220 }
221
222 input_set_drvdata(kscandat->input, kscandat);
223
224 kscandat->kscan_base = devm_ioremap_resource(&pdev->dev, res);
225 if (IS_ERR(kscandat->kscan_base))
226 return PTR_ERR(kscandat->kscan_base);
227
228
229 kscandat->clk = devm_clk_get(&pdev->dev, NULL);
230 if (IS_ERR(kscandat->clk)) {
231 dev_err(&pdev->dev, "failed to get clock\n");
232 return PTR_ERR(kscandat->clk);
233 }
234
235
236 error = clk_prepare_enable(kscandat->clk);
237 if (error)
238 return error;
239
240 writel(kscandat->deb_clks, LPC32XX_KS_DEB(kscandat->kscan_base));
241 writel(kscandat->scan_delay, LPC32XX_KS_SCAN_CTL(kscandat->kscan_base));
242 writel(LPC32XX_KSCAN_FTST_USE32K_CLK,
243 LPC32XX_KS_FAST_TST(kscandat->kscan_base));
244 writel(kscandat->matrix_sz,
245 LPC32XX_KS_MATRIX_DIM(kscandat->kscan_base));
246 writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
247 clk_disable_unprepare(kscandat->clk);
248
249 error = devm_request_irq(&pdev->dev, irq, lpc32xx_kscan_irq, 0,
250 pdev->name, kscandat);
251 if (error) {
252 dev_err(&pdev->dev, "failed to request irq\n");
253 return error;
254 }
255
256 error = input_register_device(kscandat->input);
257 if (error) {
258 dev_err(&pdev->dev, "failed to register input device\n");
259 return error;
260 }
261
262 platform_set_drvdata(pdev, kscandat);
263
264 return 0;
265}
266
267#ifdef CONFIG_PM_SLEEP
268static int lpc32xx_kscan_suspend(struct device *dev)
269{
270 struct platform_device *pdev = to_platform_device(dev);
271 struct lpc32xx_kscan_drv *kscandat = platform_get_drvdata(pdev);
272 struct input_dev *input = kscandat->input;
273
274 mutex_lock(&input->mutex);
275
276 if (input_device_enabled(input)) {
277
278 writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
279 clk_disable_unprepare(kscandat->clk);
280 }
281
282 mutex_unlock(&input->mutex);
283 return 0;
284}
285
286static int lpc32xx_kscan_resume(struct device *dev)
287{
288 struct platform_device *pdev = to_platform_device(dev);
289 struct lpc32xx_kscan_drv *kscandat = platform_get_drvdata(pdev);
290 struct input_dev *input = kscandat->input;
291 int retval = 0;
292
293 mutex_lock(&input->mutex);
294
295 if (input_device_enabled(input)) {
296
297 retval = clk_prepare_enable(kscandat->clk);
298 if (retval == 0)
299 writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
300 }
301
302 mutex_unlock(&input->mutex);
303 return retval;
304}
305#endif
306
307static SIMPLE_DEV_PM_OPS(lpc32xx_kscan_pm_ops, lpc32xx_kscan_suspend,
308 lpc32xx_kscan_resume);
309
310static const struct of_device_id lpc32xx_kscan_match[] = {
311 { .compatible = "nxp,lpc3220-key" },
312 {},
313};
314MODULE_DEVICE_TABLE(of, lpc32xx_kscan_match);
315
316static struct platform_driver lpc32xx_kscan_driver = {
317 .probe = lpc32xx_kscan_probe,
318 .driver = {
319 .name = DRV_NAME,
320 .pm = &lpc32xx_kscan_pm_ops,
321 .of_match_table = lpc32xx_kscan_match,
322 }
323};
324
325module_platform_driver(lpc32xx_kscan_driver);
326
327MODULE_LICENSE("GPL");
328MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>");
329MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
330MODULE_DESCRIPTION("Key scanner driver for LPC32XX devices");
331
