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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * NXP LPC32xx SoC Key Scan Interface
4 *
5 * Authors:
6 * Kevin Wells <kevin.wells@nxp.com>
7 * Roland Stigge <stigge@antcom.de>
8 *
9 * Copyright (C) 2010 NXP Semiconductors
10 * Copyright (C) 2012 Roland Stigge
11 *
12 * This controller supports square key matrices from 1x1 up to 8x8
13 */
14
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 * Key scanner register offsets
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) /* 1..8 */
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; /* Size of matrix in XxY, ie. 3 = 3x3 */
63 u32 deb_clks; /* Debounce clocks (based on 32KHz clock) */
64 u32 scan_delay; /* Scan delay (based on 32KHz clock) */
65
66 unsigned short *keymap; /* Pointer to key map for the scan matrix */
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 /* Key state changed, signal an event */
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 /* Setup key input */
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 /* Get the key scanner clock */
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 /* Configure the key scanner */
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
267static int lpc32xx_kscan_suspend(struct device *dev)
268{
269 struct platform_device *pdev = to_platform_device(dev);
270 struct lpc32xx_kscan_drv *kscandat = platform_get_drvdata(pdev);
271 struct input_dev *input = kscandat->input;
272
273 mutex_lock(&input->mutex);
274
275 if (input_device_enabled(input)) {
276 /* Clear IRQ and disable clock */
277 writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
278 clk_disable_unprepare(kscandat->clk);
279 }
280
281 mutex_unlock(&input->mutex);
282 return 0;
283}
284
285static int lpc32xx_kscan_resume(struct device *dev)
286{
287 struct platform_device *pdev = to_platform_device(dev);
288 struct lpc32xx_kscan_drv *kscandat = platform_get_drvdata(pdev);
289 struct input_dev *input = kscandat->input;
290 int retval = 0;
291
292 mutex_lock(&input->mutex);
293
294 if (input_device_enabled(input)) {
295 /* Enable clock and clear IRQ */
296 retval = clk_prepare_enable(kscandat->clk);
297 if (retval == 0)
298 writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
299 }
300
301 mutex_unlock(&input->mutex);
302 return retval;
303}
304
305static DEFINE_SIMPLE_DEV_PM_OPS(lpc32xx_kscan_pm_ops, lpc32xx_kscan_suspend,
306 lpc32xx_kscan_resume);
307
308static const struct of_device_id lpc32xx_kscan_match[] = {
309 { .compatible = "nxp,lpc3220-key" },
310 {},
311};
312MODULE_DEVICE_TABLE(of, lpc32xx_kscan_match);
313
314static struct platform_driver lpc32xx_kscan_driver = {
315 .probe = lpc32xx_kscan_probe,
316 .driver = {
317 .name = DRV_NAME,
318 .pm = pm_sleep_ptr(&lpc32xx_kscan_pm_ops),
319 .of_match_table = lpc32xx_kscan_match,
320 }
321};
322
323module_platform_driver(lpc32xx_kscan_driver);
324
325MODULE_LICENSE("GPL");
326MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>");
327MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
328MODULE_DESCRIPTION("Key scanner driver for LPC32XX devices");
1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * NXP LPC32xx SoC Key Scan Interface
4 *
5 * Authors:
6 * Kevin Wells <kevin.wells@nxp.com>
7 * Roland Stigge <stigge@antcom.de>
8 *
9 * Copyright (C) 2010 NXP Semiconductors
10 * Copyright (C) 2012 Roland Stigge
11 *
12 * This controller supports square key matrices from 1x1 up to 8x8
13 */
14
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 * Key scanner register offsets
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) /* 1..8 */
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; /* Size of matrix in XxY, ie. 3 = 3x3 */
63 u32 deb_clks; /* Debounce clocks (based on 32KHz clock) */
64 u32 scan_delay; /* Scan delay (based on 32KHz clock) */
65
66 unsigned short *keymap; /* Pointer to key map for the scan matrix */
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 /* Key state changed, signal an event */
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 size_t keymap_size;
164 int error;
165 int irq;
166
167 irq = platform_get_irq(pdev, 0);
168 if (irq < 0)
169 return -EINVAL;
170
171 kscandat = devm_kzalloc(&pdev->dev, sizeof(*kscandat),
172 GFP_KERNEL);
173 if (!kscandat)
174 return -ENOMEM;
175
176 error = lpc32xx_parse_dt(&pdev->dev, kscandat);
177 if (error) {
178 dev_err(&pdev->dev, "failed to parse device tree\n");
179 return error;
180 }
181
182 keymap_size = sizeof(kscandat->keymap[0]) *
183 (kscandat->matrix_sz << kscandat->row_shift);
184 kscandat->keymap = devm_kzalloc(&pdev->dev, keymap_size, GFP_KERNEL);
185 if (!kscandat->keymap)
186 return -ENOMEM;
187
188 kscandat->input = input = devm_input_allocate_device(&pdev->dev);
189 if (!input) {
190 dev_err(&pdev->dev, "failed to allocate input device\n");
191 return -ENOMEM;
192 }
193
194 /* Setup key input */
195 input->name = pdev->name;
196 input->phys = "lpc32xx/input0";
197 input->id.vendor = 0x0001;
198 input->id.product = 0x0001;
199 input->id.version = 0x0100;
200 input->open = lpc32xx_kscan_open;
201 input->close = lpc32xx_kscan_close;
202 input->dev.parent = &pdev->dev;
203
204 input_set_capability(input, EV_MSC, MSC_SCAN);
205
206 error = matrix_keypad_build_keymap(NULL, NULL,
207 kscandat->matrix_sz,
208 kscandat->matrix_sz,
209 kscandat->keymap, kscandat->input);
210 if (error) {
211 dev_err(&pdev->dev, "failed to build keymap\n");
212 return error;
213 }
214
215 input_set_drvdata(kscandat->input, kscandat);
216
217 kscandat->kscan_base = devm_platform_ioremap_resource(pdev, 0);
218 if (IS_ERR(kscandat->kscan_base))
219 return PTR_ERR(kscandat->kscan_base);
220
221 /* Get the key scanner clock */
222 kscandat->clk = devm_clk_get(&pdev->dev, NULL);
223 if (IS_ERR(kscandat->clk)) {
224 dev_err(&pdev->dev, "failed to get clock\n");
225 return PTR_ERR(kscandat->clk);
226 }
227
228 /* Configure the key scanner */
229 error = clk_prepare_enable(kscandat->clk);
230 if (error)
231 return error;
232
233 writel(kscandat->deb_clks, LPC32XX_KS_DEB(kscandat->kscan_base));
234 writel(kscandat->scan_delay, LPC32XX_KS_SCAN_CTL(kscandat->kscan_base));
235 writel(LPC32XX_KSCAN_FTST_USE32K_CLK,
236 LPC32XX_KS_FAST_TST(kscandat->kscan_base));
237 writel(kscandat->matrix_sz,
238 LPC32XX_KS_MATRIX_DIM(kscandat->kscan_base));
239 writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
240 clk_disable_unprepare(kscandat->clk);
241
242 error = devm_request_irq(&pdev->dev, irq, lpc32xx_kscan_irq, 0,
243 pdev->name, kscandat);
244 if (error) {
245 dev_err(&pdev->dev, "failed to request irq\n");
246 return error;
247 }
248
249 error = input_register_device(kscandat->input);
250 if (error) {
251 dev_err(&pdev->dev, "failed to register input device\n");
252 return error;
253 }
254
255 platform_set_drvdata(pdev, kscandat);
256
257 return 0;
258}
259
260static int lpc32xx_kscan_suspend(struct device *dev)
261{
262 struct platform_device *pdev = to_platform_device(dev);
263 struct lpc32xx_kscan_drv *kscandat = platform_get_drvdata(pdev);
264 struct input_dev *input = kscandat->input;
265
266 mutex_lock(&input->mutex);
267
268 if (input_device_enabled(input)) {
269 /* Clear IRQ and disable clock */
270 writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
271 clk_disable_unprepare(kscandat->clk);
272 }
273
274 mutex_unlock(&input->mutex);
275 return 0;
276}
277
278static int lpc32xx_kscan_resume(struct device *dev)
279{
280 struct platform_device *pdev = to_platform_device(dev);
281 struct lpc32xx_kscan_drv *kscandat = platform_get_drvdata(pdev);
282 struct input_dev *input = kscandat->input;
283 int retval = 0;
284
285 mutex_lock(&input->mutex);
286
287 if (input_device_enabled(input)) {
288 /* Enable clock and clear IRQ */
289 retval = clk_prepare_enable(kscandat->clk);
290 if (retval == 0)
291 writel(1, LPC32XX_KS_IRQ(kscandat->kscan_base));
292 }
293
294 mutex_unlock(&input->mutex);
295 return retval;
296}
297
298static DEFINE_SIMPLE_DEV_PM_OPS(lpc32xx_kscan_pm_ops, lpc32xx_kscan_suspend,
299 lpc32xx_kscan_resume);
300
301static const struct of_device_id lpc32xx_kscan_match[] = {
302 { .compatible = "nxp,lpc3220-key" },
303 {},
304};
305MODULE_DEVICE_TABLE(of, lpc32xx_kscan_match);
306
307static struct platform_driver lpc32xx_kscan_driver = {
308 .probe = lpc32xx_kscan_probe,
309 .driver = {
310 .name = DRV_NAME,
311 .pm = pm_sleep_ptr(&lpc32xx_kscan_pm_ops),
312 .of_match_table = lpc32xx_kscan_match,
313 }
314};
315
316module_platform_driver(lpc32xx_kscan_driver);
317
318MODULE_LICENSE("GPL");
319MODULE_AUTHOR("Kevin Wells <kevin.wells@nxp.com>");
320MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
321MODULE_DESCRIPTION("Key scanner driver for LPC32XX devices");