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1/*
2 * ChromeOS EC keyboard driver
3 *
4 * Copyright (C) 2012 Google, Inc
5 *
6 * This software is licensed under the terms of the GNU General Public
7 * License version 2, as published by the Free Software Foundation, and
8 * may be copied, distributed, and modified under those terms.
9 *
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
14 *
15 * This driver uses the Chrome OS EC byte-level message-based protocol for
16 * communicating the keyboard state (which keys are pressed) from a keyboard EC
17 * to the AP over some bus (such as i2c, lpc, spi). The EC does debouncing,
18 * but everything else (including deghosting) is done here. The main
19 * motivation for this is to keep the EC firmware as simple as possible, since
20 * it cannot be easily upgraded and EC flash/IRAM space is relatively
21 * expensive.
22 */
23
24#include <linux/module.h>
25#include <linux/bitops.h>
26#include <linux/i2c.h>
27#include <linux/input.h>
28#include <linux/interrupt.h>
29#include <linux/kernel.h>
30#include <linux/platform_device.h>
31#include <linux/slab.h>
32#include <linux/input/matrix_keypad.h>
33#include <linux/mfd/cros_ec.h>
34#include <linux/mfd/cros_ec_commands.h>
35
36/*
37 * @rows: Number of rows in the keypad
38 * @cols: Number of columns in the keypad
39 * @row_shift: log2 or number of rows, rounded up
40 * @keymap_data: Matrix keymap data used to convert to keyscan values
41 * @ghost_filter: true to enable the matrix key-ghosting filter
42 * @valid_keys: bitmap of existing keys for each matrix column
43 * @old_kb_state: bitmap of keys pressed last scan
44 * @dev: Device pointer
45 * @idev: Input device
46 * @ec: Top level ChromeOS device to use to talk to EC
47 */
48struct cros_ec_keyb {
49 unsigned int rows;
50 unsigned int cols;
51 int row_shift;
52 const struct matrix_keymap_data *keymap_data;
53 bool ghost_filter;
54 uint8_t *valid_keys;
55 uint8_t *old_kb_state;
56
57 struct device *dev;
58 struct input_dev *idev;
59 struct cros_ec_device *ec;
60};
61
62
63/*
64 * Returns true when there is at least one combination of pressed keys that
65 * results in ghosting.
66 */
67static bool cros_ec_keyb_has_ghosting(struct cros_ec_keyb *ckdev, uint8_t *buf)
68{
69 int col1, col2, buf1, buf2;
70 struct device *dev = ckdev->dev;
71 uint8_t *valid_keys = ckdev->valid_keys;
72
73 /*
74 * Ghosting happens if for any pressed key X there are other keys
75 * pressed both in the same row and column of X as, for instance,
76 * in the following diagram:
77 *
78 * . . Y . g .
79 * . . . . . .
80 * . . . . . .
81 * . . X . Z .
82 *
83 * In this case only X, Y, and Z are pressed, but g appears to be
84 * pressed too (see Wikipedia).
85 */
86 for (col1 = 0; col1 < ckdev->cols; col1++) {
87 buf1 = buf[col1] & valid_keys[col1];
88 for (col2 = col1 + 1; col2 < ckdev->cols; col2++) {
89 buf2 = buf[col2] & valid_keys[col2];
90 if (hweight8(buf1 & buf2) > 1) {
91 dev_dbg(dev, "ghost found at: B[%02d]:0x%02x & B[%02d]:0x%02x",
92 col1, buf1, col2, buf2);
93 return true;
94 }
95 }
96 }
97
98 return false;
99}
100
101
102/*
103 * Compares the new keyboard state to the old one and produces key
104 * press/release events accordingly. The keyboard state is 13 bytes (one byte
105 * per column)
106 */
107static void cros_ec_keyb_process(struct cros_ec_keyb *ckdev,
108 uint8_t *kb_state, int len)
109{
110 struct input_dev *idev = ckdev->idev;
111 int col, row;
112 int new_state;
113 int old_state;
114 int num_cols;
115
116 num_cols = len;
117
118 if (ckdev->ghost_filter && cros_ec_keyb_has_ghosting(ckdev, kb_state)) {
119 /*
120 * Simple-minded solution: ignore this state. The obvious
121 * improvement is to only ignore changes to keys involved in
122 * the ghosting, but process the other changes.
123 */
124 dev_dbg(ckdev->dev, "ghosting found\n");
125 return;
126 }
127
128 for (col = 0; col < ckdev->cols; col++) {
129 for (row = 0; row < ckdev->rows; row++) {
130 int pos = MATRIX_SCAN_CODE(row, col, ckdev->row_shift);
131 const unsigned short *keycodes = idev->keycode;
132
133 new_state = kb_state[col] & (1 << row);
134 old_state = ckdev->old_kb_state[col] & (1 << row);
135 if (new_state != old_state) {
136 dev_dbg(ckdev->dev,
137 "changed: [r%d c%d]: byte %02x\n",
138 row, col, new_state);
139
140 input_report_key(idev, keycodes[pos],
141 new_state);
142 }
143 }
144 ckdev->old_kb_state[col] = kb_state[col];
145 }
146 input_sync(ckdev->idev);
147}
148
149static int cros_ec_keyb_get_state(struct cros_ec_keyb *ckdev, uint8_t *kb_state)
150{
151 int ret = 0;
152 struct cros_ec_command *msg;
153
154 msg = kmalloc(sizeof(*msg) + ckdev->cols, GFP_KERNEL);
155 if (!msg)
156 return -ENOMEM;
157
158 msg->version = 0;
159 msg->command = EC_CMD_MKBP_STATE;
160 msg->insize = ckdev->cols;
161 msg->outsize = 0;
162
163 ret = cros_ec_cmd_xfer(ckdev->ec, msg);
164 if (ret < 0) {
165 dev_err(ckdev->dev, "Error transferring EC message %d\n", ret);
166 goto exit;
167 }
168
169 memcpy(kb_state, msg->data, ckdev->cols);
170exit:
171 kfree(msg);
172 return ret;
173}
174
175static irqreturn_t cros_ec_keyb_irq(int irq, void *data)
176{
177 struct cros_ec_keyb *ckdev = data;
178 struct cros_ec_device *ec = ckdev->ec;
179 int ret;
180 uint8_t kb_state[ckdev->cols];
181
182 if (device_may_wakeup(ec->dev))
183 pm_wakeup_event(ec->dev, 0);
184
185 ret = cros_ec_keyb_get_state(ckdev, kb_state);
186 if (ret >= 0)
187 cros_ec_keyb_process(ckdev, kb_state, ret);
188 else
189 dev_err(ec->dev, "failed to get keyboard state: %d\n", ret);
190
191 return IRQ_HANDLED;
192}
193
194static int cros_ec_keyb_open(struct input_dev *dev)
195{
196 struct cros_ec_keyb *ckdev = input_get_drvdata(dev);
197 struct cros_ec_device *ec = ckdev->ec;
198
199 return request_threaded_irq(ec->irq, NULL, cros_ec_keyb_irq,
200 IRQF_TRIGGER_LOW | IRQF_ONESHOT,
201 "cros_ec_keyb", ckdev);
202}
203
204static void cros_ec_keyb_close(struct input_dev *dev)
205{
206 struct cros_ec_keyb *ckdev = input_get_drvdata(dev);
207 struct cros_ec_device *ec = ckdev->ec;
208
209 free_irq(ec->irq, ckdev);
210}
211
212/*
213 * Walks keycodes flipping bit in buffer COLUMNS deep where bit is ROW. Used by
214 * ghosting logic to ignore NULL or virtual keys.
215 */
216static void cros_ec_keyb_compute_valid_keys(struct cros_ec_keyb *ckdev)
217{
218 int row, col;
219 int row_shift = ckdev->row_shift;
220 unsigned short *keymap = ckdev->idev->keycode;
221 unsigned short code;
222
223 BUG_ON(ckdev->idev->keycodesize != sizeof(*keymap));
224
225 for (col = 0; col < ckdev->cols; col++) {
226 for (row = 0; row < ckdev->rows; row++) {
227 code = keymap[MATRIX_SCAN_CODE(row, col, row_shift)];
228 if (code && (code != KEY_BATTERY))
229 ckdev->valid_keys[col] |= 1 << row;
230 }
231 dev_dbg(ckdev->dev, "valid_keys[%02d] = 0x%02x\n",
232 col, ckdev->valid_keys[col]);
233 }
234}
235
236static int cros_ec_keyb_probe(struct platform_device *pdev)
237{
238 struct cros_ec_device *ec = dev_get_drvdata(pdev->dev.parent);
239 struct device *dev = ec->dev;
240 struct cros_ec_keyb *ckdev;
241 struct input_dev *idev;
242 struct device_node *np;
243 int err;
244
245 np = pdev->dev.of_node;
246 if (!np)
247 return -ENODEV;
248
249 ckdev = devm_kzalloc(&pdev->dev, sizeof(*ckdev), GFP_KERNEL);
250 if (!ckdev)
251 return -ENOMEM;
252 err = matrix_keypad_parse_of_params(&pdev->dev, &ckdev->rows,
253 &ckdev->cols);
254 if (err)
255 return err;
256
257 ckdev->valid_keys = devm_kzalloc(&pdev->dev, ckdev->cols, GFP_KERNEL);
258 if (!ckdev->valid_keys)
259 return -ENOMEM;
260
261 ckdev->old_kb_state = devm_kzalloc(&pdev->dev, ckdev->cols, GFP_KERNEL);
262 if (!ckdev->old_kb_state)
263 return -ENOMEM;
264
265 idev = devm_input_allocate_device(&pdev->dev);
266 if (!idev)
267 return -ENOMEM;
268
269 if (!ec->irq) {
270 dev_err(dev, "no EC IRQ specified\n");
271 return -EINVAL;
272 }
273
274 ckdev->ec = ec;
275 ckdev->dev = dev;
276 dev_set_drvdata(&pdev->dev, ckdev);
277
278 idev->name = CROS_EC_DEV_NAME;
279 idev->phys = ec->phys_name;
280 __set_bit(EV_REP, idev->evbit);
281
282 idev->id.bustype = BUS_VIRTUAL;
283 idev->id.version = 1;
284 idev->id.product = 0;
285 idev->dev.parent = &pdev->dev;
286 idev->open = cros_ec_keyb_open;
287 idev->close = cros_ec_keyb_close;
288
289 ckdev->ghost_filter = of_property_read_bool(np,
290 "google,needs-ghost-filter");
291
292 err = matrix_keypad_build_keymap(NULL, NULL, ckdev->rows, ckdev->cols,
293 NULL, idev);
294 if (err) {
295 dev_err(dev, "cannot build key matrix\n");
296 return err;
297 }
298
299 ckdev->row_shift = get_count_order(ckdev->cols);
300
301 input_set_capability(idev, EV_MSC, MSC_SCAN);
302 input_set_drvdata(idev, ckdev);
303 ckdev->idev = idev;
304 cros_ec_keyb_compute_valid_keys(ckdev);
305
306 err = input_register_device(ckdev->idev);
307 if (err) {
308 dev_err(dev, "cannot register input device\n");
309 return err;
310 }
311
312 return 0;
313}
314
315#ifdef CONFIG_PM_SLEEP
316/* Clear any keys in the buffer */
317static void cros_ec_keyb_clear_keyboard(struct cros_ec_keyb *ckdev)
318{
319 uint8_t old_state[ckdev->cols];
320 uint8_t new_state[ckdev->cols];
321 unsigned long duration;
322 int i, ret;
323
324 /*
325 * Keep reading until we see that the scan state does not change.
326 * That indicates that we are done.
327 *
328 * Assume that the EC keyscan buffer is at most 32 deep.
329 */
330 duration = jiffies;
331 ret = cros_ec_keyb_get_state(ckdev, new_state);
332 for (i = 1; !ret && i < 32; i++) {
333 memcpy(old_state, new_state, sizeof(old_state));
334 ret = cros_ec_keyb_get_state(ckdev, new_state);
335 if (0 == memcmp(old_state, new_state, sizeof(old_state)))
336 break;
337 }
338 duration = jiffies - duration;
339 dev_info(ckdev->dev, "Discarded %d keyscan(s) in %dus\n", i,
340 jiffies_to_usecs(duration));
341}
342
343static int cros_ec_keyb_resume(struct device *dev)
344{
345 struct cros_ec_keyb *ckdev = dev_get_drvdata(dev);
346
347 /*
348 * When the EC is not a wake source, then it could not have caused the
349 * resume, so we clear the EC's key scan buffer. If the EC was a
350 * wake source (e.g. the lid is open and the user might press a key to
351 * wake) then the key scan buffer should be preserved.
352 */
353 if (!ckdev->ec->was_wake_device)
354 cros_ec_keyb_clear_keyboard(ckdev);
355
356 return 0;
357}
358
359#endif
360
361static SIMPLE_DEV_PM_OPS(cros_ec_keyb_pm_ops, NULL, cros_ec_keyb_resume);
362
363#ifdef CONFIG_OF
364static const struct of_device_id cros_ec_keyb_of_match[] = {
365 { .compatible = "google,cros-ec-keyb" },
366 {},
367};
368MODULE_DEVICE_TABLE(of, cros_ec_keyb_of_match);
369#endif
370
371static struct platform_driver cros_ec_keyb_driver = {
372 .probe = cros_ec_keyb_probe,
373 .driver = {
374 .name = "cros-ec-keyb",
375 .of_match_table = of_match_ptr(cros_ec_keyb_of_match),
376 .pm = &cros_ec_keyb_pm_ops,
377 },
378};
379
380module_platform_driver(cros_ec_keyb_driver);
381
382MODULE_LICENSE("GPL");
383MODULE_DESCRIPTION("ChromeOS EC keyboard driver");
384MODULE_ALIAS("platform:cros-ec-keyb");
1// SPDX-License-Identifier: GPL-2.0
2// ChromeOS EC keyboard driver
3//
4// Copyright (C) 2012 Google, Inc.
5//
6// This driver uses the ChromeOS EC byte-level message-based protocol for
7// communicating the keyboard state (which keys are pressed) from a keyboard EC
8// to the AP over some bus (such as i2c, lpc, spi). The EC does debouncing,
9// but everything else (including deghosting) is done here. The main
10// motivation for this is to keep the EC firmware as simple as possible, since
11// it cannot be easily upgraded and EC flash/IRAM space is relatively
12// expensive.
13
14#include <linux/module.h>
15#include <linux/acpi.h>
16#include <linux/bitops.h>
17#include <linux/i2c.h>
18#include <linux/input.h>
19#include <linux/input/vivaldi-fmap.h>
20#include <linux/interrupt.h>
21#include <linux/kernel.h>
22#include <linux/notifier.h>
23#include <linux/platform_device.h>
24#include <linux/slab.h>
25#include <linux/sysrq.h>
26#include <linux/input/matrix_keypad.h>
27#include <linux/platform_data/cros_ec_commands.h>
28#include <linux/platform_data/cros_ec_proto.h>
29
30#include <linux/unaligned.h>
31
32/**
33 * struct cros_ec_keyb - Structure representing EC keyboard device
34 *
35 * @rows: Number of rows in the keypad
36 * @cols: Number of columns in the keypad
37 * @row_shift: log2 or number of rows, rounded up
38 * @ghost_filter: true to enable the matrix key-ghosting filter
39 * @valid_keys: bitmap of existing keys for each matrix column
40 * @old_kb_state: bitmap of keys pressed last scan
41 * @dev: Device pointer
42 * @ec: Top level ChromeOS device to use to talk to EC
43 * @idev: The input device for the matrix keys.
44 * @bs_idev: The input device for non-matrix buttons and switches (or NULL).
45 * @notifier: interrupt event notifier for transport devices
46 * @vdata: vivaldi function row data
47 */
48struct cros_ec_keyb {
49 unsigned int rows;
50 unsigned int cols;
51 int row_shift;
52 bool ghost_filter;
53 uint8_t *valid_keys;
54 uint8_t *old_kb_state;
55
56 struct device *dev;
57 struct cros_ec_device *ec;
58
59 struct input_dev *idev;
60 struct input_dev *bs_idev;
61 struct notifier_block notifier;
62
63 struct vivaldi_data vdata;
64};
65
66/**
67 * struct cros_ec_bs_map - Mapping between Linux keycodes and EC button/switch
68 * bitmap #defines
69 *
70 * @ev_type: The type of the input event to generate (e.g., EV_KEY).
71 * @code: A linux keycode
72 * @bit: A #define like EC_MKBP_POWER_BUTTON or EC_MKBP_LID_OPEN
73 * @inverted: If the #define and EV_SW have opposite meanings, this is true.
74 * Only applicable to switches.
75 */
76struct cros_ec_bs_map {
77 unsigned int ev_type;
78 unsigned int code;
79 u8 bit;
80 bool inverted;
81};
82
83/* cros_ec_keyb_bs - Map EC button/switch #defines into kernel ones */
84static const struct cros_ec_bs_map cros_ec_keyb_bs[] = {
85 /* Buttons */
86 {
87 .ev_type = EV_KEY,
88 .code = KEY_POWER,
89 .bit = EC_MKBP_POWER_BUTTON,
90 },
91 {
92 .ev_type = EV_KEY,
93 .code = KEY_VOLUMEUP,
94 .bit = EC_MKBP_VOL_UP,
95 },
96 {
97 .ev_type = EV_KEY,
98 .code = KEY_VOLUMEDOWN,
99 .bit = EC_MKBP_VOL_DOWN,
100 },
101 {
102 .ev_type = EV_KEY,
103 .code = KEY_BRIGHTNESSUP,
104 .bit = EC_MKBP_BRI_UP,
105 },
106 {
107 .ev_type = EV_KEY,
108 .code = KEY_BRIGHTNESSDOWN,
109 .bit = EC_MKBP_BRI_DOWN,
110 },
111 {
112 .ev_type = EV_KEY,
113 .code = KEY_SCREENLOCK,
114 .bit = EC_MKBP_SCREEN_LOCK,
115 },
116
117 /* Switches */
118 {
119 .ev_type = EV_SW,
120 .code = SW_LID,
121 .bit = EC_MKBP_LID_OPEN,
122 .inverted = true,
123 },
124 {
125 .ev_type = EV_SW,
126 .code = SW_TABLET_MODE,
127 .bit = EC_MKBP_TABLET_MODE,
128 },
129};
130
131/*
132 * Returns true when there is at least one combination of pressed keys that
133 * results in ghosting.
134 */
135static bool cros_ec_keyb_has_ghosting(struct cros_ec_keyb *ckdev, uint8_t *buf)
136{
137 int col1, col2, buf1, buf2;
138 struct device *dev = ckdev->dev;
139 uint8_t *valid_keys = ckdev->valid_keys;
140
141 /*
142 * Ghosting happens if for any pressed key X there are other keys
143 * pressed both in the same row and column of X as, for instance,
144 * in the following diagram:
145 *
146 * . . Y . g .
147 * . . . . . .
148 * . . . . . .
149 * . . X . Z .
150 *
151 * In this case only X, Y, and Z are pressed, but g appears to be
152 * pressed too (see Wikipedia).
153 */
154 for (col1 = 0; col1 < ckdev->cols; col1++) {
155 buf1 = buf[col1] & valid_keys[col1];
156 for (col2 = col1 + 1; col2 < ckdev->cols; col2++) {
157 buf2 = buf[col2] & valid_keys[col2];
158 if (hweight8(buf1 & buf2) > 1) {
159 dev_dbg(dev, "ghost found at: B[%02d]:0x%02x & B[%02d]:0x%02x",
160 col1, buf1, col2, buf2);
161 return true;
162 }
163 }
164 }
165
166 return false;
167}
168
169
170/*
171 * Compares the new keyboard state to the old one and produces key
172 * press/release events accordingly. The keyboard state is 13 bytes (one byte
173 * per column)
174 */
175static void cros_ec_keyb_process(struct cros_ec_keyb *ckdev,
176 uint8_t *kb_state, int len)
177{
178 struct input_dev *idev = ckdev->idev;
179 int col, row;
180 int new_state;
181 int old_state;
182
183 if (ckdev->ghost_filter && cros_ec_keyb_has_ghosting(ckdev, kb_state)) {
184 /*
185 * Simple-minded solution: ignore this state. The obvious
186 * improvement is to only ignore changes to keys involved in
187 * the ghosting, but process the other changes.
188 */
189 dev_dbg(ckdev->dev, "ghosting found\n");
190 return;
191 }
192
193 for (col = 0; col < ckdev->cols; col++) {
194 for (row = 0; row < ckdev->rows; row++) {
195 int pos = MATRIX_SCAN_CODE(row, col, ckdev->row_shift);
196 const unsigned short *keycodes = idev->keycode;
197
198 new_state = kb_state[col] & (1 << row);
199 old_state = ckdev->old_kb_state[col] & (1 << row);
200 if (new_state != old_state) {
201 dev_dbg(ckdev->dev,
202 "changed: [r%d c%d]: byte %02x\n",
203 row, col, new_state);
204
205 input_event(idev, EV_MSC, MSC_SCAN, pos);
206 input_report_key(idev, keycodes[pos],
207 new_state);
208 }
209 }
210 ckdev->old_kb_state[col] = kb_state[col];
211 }
212 input_sync(ckdev->idev);
213}
214
215/**
216 * cros_ec_keyb_report_bs - Report non-matrixed buttons or switches
217 *
218 * This takes a bitmap of buttons or switches from the EC and reports events,
219 * syncing at the end.
220 *
221 * @ckdev: The keyboard device.
222 * @ev_type: The input event type (e.g., EV_KEY).
223 * @mask: A bitmap of buttons from the EC.
224 */
225static void cros_ec_keyb_report_bs(struct cros_ec_keyb *ckdev,
226 unsigned int ev_type, u32 mask)
227
228{
229 struct input_dev *idev = ckdev->bs_idev;
230 int i;
231
232 for (i = 0; i < ARRAY_SIZE(cros_ec_keyb_bs); i++) {
233 const struct cros_ec_bs_map *map = &cros_ec_keyb_bs[i];
234
235 if (map->ev_type != ev_type)
236 continue;
237
238 input_event(idev, ev_type, map->code,
239 !!(mask & BIT(map->bit)) ^ map->inverted);
240 }
241 input_sync(idev);
242}
243
244static int cros_ec_keyb_work(struct notifier_block *nb,
245 unsigned long queued_during_suspend, void *_notify)
246{
247 struct cros_ec_keyb *ckdev = container_of(nb, struct cros_ec_keyb,
248 notifier);
249 u32 val;
250 unsigned int ev_type;
251
252 /*
253 * If not wake enabled, discard key state changes during
254 * suspend. Switches will be re-checked in
255 * cros_ec_keyb_resume() to be sure nothing is lost.
256 */
257 if (queued_during_suspend && !device_may_wakeup(ckdev->dev))
258 return NOTIFY_OK;
259
260 switch (ckdev->ec->event_data.event_type) {
261 case EC_MKBP_EVENT_KEY_MATRIX:
262 pm_wakeup_event(ckdev->dev, 0);
263
264 if (ckdev->ec->event_size != ckdev->cols) {
265 dev_err(ckdev->dev,
266 "Discarded incomplete key matrix event.\n");
267 return NOTIFY_OK;
268 }
269
270 cros_ec_keyb_process(ckdev,
271 ckdev->ec->event_data.data.key_matrix,
272 ckdev->ec->event_size);
273 break;
274
275 case EC_MKBP_EVENT_SYSRQ:
276 pm_wakeup_event(ckdev->dev, 0);
277
278 val = get_unaligned_le32(&ckdev->ec->event_data.data.sysrq);
279 dev_dbg(ckdev->dev, "sysrq code from EC: %#x\n", val);
280 handle_sysrq(val);
281 break;
282
283 case EC_MKBP_EVENT_BUTTON:
284 case EC_MKBP_EVENT_SWITCH:
285 pm_wakeup_event(ckdev->dev, 0);
286
287 if (ckdev->ec->event_data.event_type == EC_MKBP_EVENT_BUTTON) {
288 val = get_unaligned_le32(
289 &ckdev->ec->event_data.data.buttons);
290 ev_type = EV_KEY;
291 } else {
292 val = get_unaligned_le32(
293 &ckdev->ec->event_data.data.switches);
294 ev_type = EV_SW;
295 }
296 cros_ec_keyb_report_bs(ckdev, ev_type, val);
297 break;
298
299 default:
300 return NOTIFY_DONE;
301 }
302
303 return NOTIFY_OK;
304}
305
306/*
307 * Walks keycodes flipping bit in buffer COLUMNS deep where bit is ROW. Used by
308 * ghosting logic to ignore NULL or virtual keys.
309 */
310static void cros_ec_keyb_compute_valid_keys(struct cros_ec_keyb *ckdev)
311{
312 int row, col;
313 int row_shift = ckdev->row_shift;
314 unsigned short *keymap = ckdev->idev->keycode;
315 unsigned short code;
316
317 BUG_ON(ckdev->idev->keycodesize != sizeof(*keymap));
318
319 for (col = 0; col < ckdev->cols; col++) {
320 for (row = 0; row < ckdev->rows; row++) {
321 code = keymap[MATRIX_SCAN_CODE(row, col, row_shift)];
322 if (code && (code != KEY_BATTERY))
323 ckdev->valid_keys[col] |= 1 << row;
324 }
325 dev_dbg(ckdev->dev, "valid_keys[%02d] = 0x%02x\n",
326 col, ckdev->valid_keys[col]);
327 }
328}
329
330/**
331 * cros_ec_keyb_info - Wrap the EC command EC_CMD_MKBP_INFO
332 *
333 * This wraps the EC_CMD_MKBP_INFO, abstracting out all of the marshalling and
334 * unmarshalling and different version nonsense into something simple.
335 *
336 * @ec_dev: The EC device
337 * @info_type: Either EC_MKBP_INFO_SUPPORTED or EC_MKBP_INFO_CURRENT.
338 * @event_type: Either EC_MKBP_EVENT_BUTTON or EC_MKBP_EVENT_SWITCH. Actually
339 * in some cases this could be EC_MKBP_EVENT_KEY_MATRIX or
340 * EC_MKBP_EVENT_HOST_EVENT too but we don't use in this driver.
341 * @result: Where we'll store the result; a union
342 * @result_size: The size of the result. Expected to be the size of one of
343 * the elements in the union.
344 *
345 * Returns 0 if no error or -error upon error.
346 */
347static int cros_ec_keyb_info(struct cros_ec_device *ec_dev,
348 enum ec_mkbp_info_type info_type,
349 enum ec_mkbp_event event_type,
350 union ec_response_get_next_data *result,
351 size_t result_size)
352{
353 struct ec_params_mkbp_info *params;
354 struct cros_ec_command *msg;
355 int ret;
356
357 msg = kzalloc(sizeof(*msg) + max_t(size_t, result_size,
358 sizeof(*params)), GFP_KERNEL);
359 if (!msg)
360 return -ENOMEM;
361
362 msg->command = EC_CMD_MKBP_INFO;
363 msg->version = 1;
364 msg->outsize = sizeof(*params);
365 msg->insize = result_size;
366 params = (struct ec_params_mkbp_info *)msg->data;
367 params->info_type = info_type;
368 params->event_type = event_type;
369
370 ret = cros_ec_cmd_xfer_status(ec_dev, msg);
371 if (ret == -ENOPROTOOPT) {
372 /* With older ECs we just return 0 for everything */
373 memset(result, 0, result_size);
374 ret = 0;
375 } else if (ret < 0) {
376 dev_warn(ec_dev->dev, "Transfer error %d/%d: %d\n",
377 (int)info_type, (int)event_type, ret);
378 } else if (ret != result_size) {
379 dev_warn(ec_dev->dev, "Wrong size %d/%d: %d != %zu\n",
380 (int)info_type, (int)event_type,
381 ret, result_size);
382 ret = -EPROTO;
383 } else {
384 memcpy(result, msg->data, result_size);
385 ret = 0;
386 }
387
388 kfree(msg);
389
390 return ret;
391}
392
393/**
394 * cros_ec_keyb_query_switches - Query the state of switches and report
395 *
396 * This will ask the EC about the current state of switches and report to the
397 * kernel. Note that we don't query for buttons because they are more
398 * transitory and we'll get an update on the next release / press.
399 *
400 * @ckdev: The keyboard device
401 *
402 * Returns 0 if no error or -error upon error.
403 */
404static int cros_ec_keyb_query_switches(struct cros_ec_keyb *ckdev)
405{
406 struct cros_ec_device *ec_dev = ckdev->ec;
407 union ec_response_get_next_data event_data = {};
408 int ret;
409
410 ret = cros_ec_keyb_info(ec_dev, EC_MKBP_INFO_CURRENT,
411 EC_MKBP_EVENT_SWITCH, &event_data,
412 sizeof(event_data.switches));
413 if (ret)
414 return ret;
415
416 cros_ec_keyb_report_bs(ckdev, EV_SW,
417 get_unaligned_le32(&event_data.switches));
418
419 return 0;
420}
421
422/**
423 * cros_ec_keyb_resume - Resume the keyboard
424 *
425 * We use the resume notification as a chance to query the EC for switches.
426 *
427 * @dev: The keyboard device
428 *
429 * Returns 0 if no error or -error upon error.
430 */
431static int cros_ec_keyb_resume(struct device *dev)
432{
433 struct cros_ec_keyb *ckdev = dev_get_drvdata(dev);
434
435 if (ckdev->bs_idev)
436 return cros_ec_keyb_query_switches(ckdev);
437
438 return 0;
439}
440
441/**
442 * cros_ec_keyb_register_bs - Register non-matrix buttons/switches
443 *
444 * Handles all the bits of the keyboard driver related to non-matrix buttons
445 * and switches, including asking the EC about which are present and telling
446 * the kernel to expect them.
447 *
448 * If this device has no support for buttons and switches we'll return no error
449 * but the ckdev->bs_idev will remain NULL when this function exits.
450 *
451 * @ckdev: The keyboard device
452 * @expect_buttons_switches: Indicates that EC must report button and/or
453 * switch events
454 *
455 * Returns 0 if no error or -error upon error.
456 */
457static int cros_ec_keyb_register_bs(struct cros_ec_keyb *ckdev,
458 bool expect_buttons_switches)
459{
460 struct cros_ec_device *ec_dev = ckdev->ec;
461 struct device *dev = ckdev->dev;
462 struct input_dev *idev;
463 union ec_response_get_next_data event_data = {};
464 const char *phys;
465 u32 buttons;
466 u32 switches;
467 int ret;
468 int i;
469
470 ret = cros_ec_keyb_info(ec_dev, EC_MKBP_INFO_SUPPORTED,
471 EC_MKBP_EVENT_BUTTON, &event_data,
472 sizeof(event_data.buttons));
473 if (ret)
474 return ret;
475 buttons = get_unaligned_le32(&event_data.buttons);
476
477 ret = cros_ec_keyb_info(ec_dev, EC_MKBP_INFO_SUPPORTED,
478 EC_MKBP_EVENT_SWITCH, &event_data,
479 sizeof(event_data.switches));
480 if (ret)
481 return ret;
482 switches = get_unaligned_le32(&event_data.switches);
483
484 if (!buttons && !switches)
485 return expect_buttons_switches ? -EINVAL : 0;
486
487 /*
488 * We call the non-matrix buttons/switches 'input1', if present.
489 * Allocate phys before input dev, to ensure correct tear-down
490 * ordering.
491 */
492 phys = devm_kasprintf(dev, GFP_KERNEL, "%s/input1", ec_dev->phys_name);
493 if (!phys)
494 return -ENOMEM;
495
496 idev = devm_input_allocate_device(dev);
497 if (!idev)
498 return -ENOMEM;
499
500 idev->name = "cros_ec_buttons";
501 idev->phys = phys;
502 __set_bit(EV_REP, idev->evbit);
503
504 idev->id.bustype = BUS_VIRTUAL;
505 idev->id.version = 1;
506 idev->id.product = 0;
507 idev->dev.parent = dev;
508
509 input_set_drvdata(idev, ckdev);
510 ckdev->bs_idev = idev;
511
512 for (i = 0; i < ARRAY_SIZE(cros_ec_keyb_bs); i++) {
513 const struct cros_ec_bs_map *map = &cros_ec_keyb_bs[i];
514
515 if ((map->ev_type == EV_KEY && (buttons & BIT(map->bit))) ||
516 (map->ev_type == EV_SW && (switches & BIT(map->bit))))
517 input_set_capability(idev, map->ev_type, map->code);
518 }
519
520 ret = cros_ec_keyb_query_switches(ckdev);
521 if (ret) {
522 dev_err(dev, "cannot query switches\n");
523 return ret;
524 }
525
526 ret = input_register_device(ckdev->bs_idev);
527 if (ret) {
528 dev_err(dev, "cannot register input device\n");
529 return ret;
530 }
531
532 return 0;
533}
534
535static void cros_ec_keyb_parse_vivaldi_physmap(struct cros_ec_keyb *ckdev)
536{
537 u32 *physmap = ckdev->vdata.function_row_physmap;
538 unsigned int row, col, scancode;
539 int n_physmap;
540 int error;
541 int i;
542
543 n_physmap = device_property_count_u32(ckdev->dev,
544 "function-row-physmap");
545 if (n_physmap <= 0)
546 return;
547
548 if (n_physmap >= VIVALDI_MAX_FUNCTION_ROW_KEYS) {
549 dev_warn(ckdev->dev,
550 "only up to %d top row keys is supported (%d specified)\n",
551 VIVALDI_MAX_FUNCTION_ROW_KEYS, n_physmap);
552 n_physmap = VIVALDI_MAX_FUNCTION_ROW_KEYS;
553 }
554
555 error = device_property_read_u32_array(ckdev->dev,
556 "function-row-physmap",
557 physmap, n_physmap);
558 if (error) {
559 dev_warn(ckdev->dev,
560 "failed to parse function-row-physmap property: %d\n",
561 error);
562 return;
563 }
564
565 /*
566 * Convert (in place) from row/column encoding to matrix "scancode"
567 * used by the driver.
568 */
569 for (i = 0; i < n_physmap; i++) {
570 row = KEY_ROW(physmap[i]);
571 col = KEY_COL(physmap[i]);
572 scancode = MATRIX_SCAN_CODE(row, col, ckdev->row_shift);
573 physmap[i] = scancode;
574 }
575
576 ckdev->vdata.num_function_row_keys = n_physmap;
577}
578
579/**
580 * cros_ec_keyb_register_matrix - Register matrix keys
581 *
582 * Handles all the bits of the keyboard driver related to matrix keys.
583 *
584 * @ckdev: The keyboard device
585 *
586 * Returns 0 if no error or -error upon error.
587 */
588static int cros_ec_keyb_register_matrix(struct cros_ec_keyb *ckdev)
589{
590 struct cros_ec_device *ec_dev = ckdev->ec;
591 struct device *dev = ckdev->dev;
592 struct input_dev *idev;
593 const char *phys;
594 int err;
595
596 err = matrix_keypad_parse_properties(dev, &ckdev->rows, &ckdev->cols);
597 if (err)
598 return err;
599
600 ckdev->valid_keys = devm_kzalloc(dev, ckdev->cols, GFP_KERNEL);
601 if (!ckdev->valid_keys)
602 return -ENOMEM;
603
604 ckdev->old_kb_state = devm_kzalloc(dev, ckdev->cols, GFP_KERNEL);
605 if (!ckdev->old_kb_state)
606 return -ENOMEM;
607
608 /*
609 * We call the keyboard matrix 'input0'. Allocate phys before input
610 * dev, to ensure correct tear-down ordering.
611 */
612 phys = devm_kasprintf(dev, GFP_KERNEL, "%s/input0", ec_dev->phys_name);
613 if (!phys)
614 return -ENOMEM;
615
616 idev = devm_input_allocate_device(dev);
617 if (!idev)
618 return -ENOMEM;
619
620 idev->name = CROS_EC_DEV_NAME;
621 idev->phys = phys;
622 __set_bit(EV_REP, idev->evbit);
623
624 idev->id.bustype = BUS_VIRTUAL;
625 idev->id.version = 1;
626 idev->id.product = 0;
627 idev->dev.parent = dev;
628
629 ckdev->ghost_filter = device_property_read_bool(dev,
630 "google,needs-ghost-filter");
631
632 err = matrix_keypad_build_keymap(NULL, NULL, ckdev->rows, ckdev->cols,
633 NULL, idev);
634 if (err) {
635 dev_err(dev, "cannot build key matrix\n");
636 return err;
637 }
638
639 ckdev->row_shift = get_count_order(ckdev->cols);
640
641 input_set_capability(idev, EV_MSC, MSC_SCAN);
642 input_set_drvdata(idev, ckdev);
643 ckdev->idev = idev;
644 cros_ec_keyb_compute_valid_keys(ckdev);
645 cros_ec_keyb_parse_vivaldi_physmap(ckdev);
646
647 err = input_register_device(ckdev->idev);
648 if (err) {
649 dev_err(dev, "cannot register input device\n");
650 return err;
651 }
652
653 return 0;
654}
655
656static ssize_t function_row_physmap_show(struct device *dev,
657 struct device_attribute *attr,
658 char *buf)
659{
660 const struct cros_ec_keyb *ckdev = dev_get_drvdata(dev);
661 const struct vivaldi_data *data = &ckdev->vdata;
662
663 return vivaldi_function_row_physmap_show(data, buf);
664}
665
666static DEVICE_ATTR_RO(function_row_physmap);
667
668static struct attribute *cros_ec_keyb_attrs[] = {
669 &dev_attr_function_row_physmap.attr,
670 NULL,
671};
672
673static umode_t cros_ec_keyb_attr_is_visible(struct kobject *kobj,
674 struct attribute *attr,
675 int n)
676{
677 struct device *dev = kobj_to_dev(kobj);
678 struct cros_ec_keyb *ckdev = dev_get_drvdata(dev);
679
680 if (attr == &dev_attr_function_row_physmap.attr &&
681 !ckdev->vdata.num_function_row_keys)
682 return 0;
683
684 return attr->mode;
685}
686
687static const struct attribute_group cros_ec_keyb_group = {
688 .is_visible = cros_ec_keyb_attr_is_visible,
689 .attrs = cros_ec_keyb_attrs,
690};
691__ATTRIBUTE_GROUPS(cros_ec_keyb);
692
693static int cros_ec_keyb_probe(struct platform_device *pdev)
694{
695 struct cros_ec_device *ec;
696 struct device *dev = &pdev->dev;
697 struct cros_ec_keyb *ckdev;
698 bool buttons_switches_only = device_get_match_data(dev);
699 int err;
700
701 /*
702 * If the parent ec device has not been probed yet, defer the probe of
703 * this keyboard/button driver until later.
704 */
705 ec = dev_get_drvdata(pdev->dev.parent);
706 if (!ec)
707 return -EPROBE_DEFER;
708
709 ckdev = devm_kzalloc(dev, sizeof(*ckdev), GFP_KERNEL);
710 if (!ckdev)
711 return -ENOMEM;
712
713 ckdev->ec = ec;
714 ckdev->dev = dev;
715 dev_set_drvdata(dev, ckdev);
716
717 if (!buttons_switches_only) {
718 err = cros_ec_keyb_register_matrix(ckdev);
719 if (err) {
720 dev_err(dev, "cannot register matrix inputs: %d\n",
721 err);
722 return err;
723 }
724 }
725
726 err = cros_ec_keyb_register_bs(ckdev, buttons_switches_only);
727 if (err) {
728 dev_err(dev, "cannot register non-matrix inputs: %d\n", err);
729 return err;
730 }
731
732 ckdev->notifier.notifier_call = cros_ec_keyb_work;
733 err = blocking_notifier_chain_register(&ckdev->ec->event_notifier,
734 &ckdev->notifier);
735 if (err) {
736 dev_err(dev, "cannot register notifier: %d\n", err);
737 return err;
738 }
739
740 device_init_wakeup(ckdev->dev, true);
741 return 0;
742}
743
744static void cros_ec_keyb_remove(struct platform_device *pdev)
745{
746 struct cros_ec_keyb *ckdev = dev_get_drvdata(&pdev->dev);
747
748 blocking_notifier_chain_unregister(&ckdev->ec->event_notifier,
749 &ckdev->notifier);
750}
751
752#ifdef CONFIG_ACPI
753static const struct acpi_device_id cros_ec_keyb_acpi_match[] = {
754 { "GOOG0007", true },
755 { }
756};
757MODULE_DEVICE_TABLE(acpi, cros_ec_keyb_acpi_match);
758#endif
759
760#ifdef CONFIG_OF
761static const struct of_device_id cros_ec_keyb_of_match[] = {
762 { .compatible = "google,cros-ec-keyb" },
763 { .compatible = "google,cros-ec-keyb-switches", .data = (void *)true },
764 {}
765};
766MODULE_DEVICE_TABLE(of, cros_ec_keyb_of_match);
767#endif
768
769static DEFINE_SIMPLE_DEV_PM_OPS(cros_ec_keyb_pm_ops, NULL, cros_ec_keyb_resume);
770
771static struct platform_driver cros_ec_keyb_driver = {
772 .probe = cros_ec_keyb_probe,
773 .remove = cros_ec_keyb_remove,
774 .driver = {
775 .name = "cros-ec-keyb",
776 .dev_groups = cros_ec_keyb_groups,
777 .of_match_table = of_match_ptr(cros_ec_keyb_of_match),
778 .acpi_match_table = ACPI_PTR(cros_ec_keyb_acpi_match),
779 .pm = pm_sleep_ptr(&cros_ec_keyb_pm_ops),
780 },
781};
782
783module_platform_driver(cros_ec_keyb_driver);
784
785MODULE_LICENSE("GPL v2");
786MODULE_DESCRIPTION("ChromeOS EC keyboard driver");
787MODULE_ALIAS("platform:cros-ec-keyb");