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