![Linus Torvalds](/assets/img/avatar_default.png)
Pull second round of input updates from Dmitry Torokhov: "Mostly simple bug fixes, although we do have one brand new driver for Microchip AR1021 i2c touchscreen. Also there is the change to stop trying to use i8042 active multiplexing by default (it is still possible to activate it via i8042.nomux=0 on boxes that implement it)" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input: Input: xpad - add Thrustmaster as Xbox 360 controller vendor Input: xpad - add USB ID for Thrustmaster Ferrari 458 Racing Wheel Input: max77693-haptic - fix state check in imax77693_haptic_disable() Input: xen-kbdfront - free grant table entry in xenkbd_disconnect_backend Input: alps - fix v4 button press recognition Input: i8042 - disable active multiplexing by default Input: i8042 - add noloop quirk for Asus X750LN Input: synaptics - gate forcepad support by DMI check Input: Add Microchip AR1021 i2c touchscreen Input: cros_ec_keyb - add of match table Input: serio - avoid negative serio device numbers Input: avoid negative input device numbers Input: automatically set EV_ABS bit in input_set_abs_params Input: adp5588-keys - cancel workqueue in failure path Input: opencores-kbd - switch to using managed resources Input: evdev - fix EVIOCG{type} ioctl
373 lines
9.8 KiB
C
373 lines
9.8 KiB
C
/*
|
|
* ChromeOS EC keyboard driver
|
|
*
|
|
* Copyright (C) 2012 Google, Inc
|
|
*
|
|
* This software is licensed under the terms of the GNU General Public
|
|
* License version 2, as published by the Free Software Foundation, and
|
|
* may be copied, distributed, and modified under those terms.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU General Public License for more details.
|
|
*
|
|
* This driver uses the Chrome OS EC byte-level message-based protocol for
|
|
* communicating the keyboard state (which keys are pressed) from a keyboard EC
|
|
* to the AP over some bus (such as i2c, lpc, spi). The EC does debouncing,
|
|
* but everything else (including deghosting) is done here. The main
|
|
* motivation for this is to keep the EC firmware as simple as possible, since
|
|
* it cannot be easily upgraded and EC flash/IRAM space is relatively
|
|
* expensive.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/bitops.h>
|
|
#include <linux/i2c.h>
|
|
#include <linux/input.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/platform_device.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/input/matrix_keypad.h>
|
|
#include <linux/mfd/cros_ec.h>
|
|
#include <linux/mfd/cros_ec_commands.h>
|
|
|
|
/*
|
|
* @rows: Number of rows in the keypad
|
|
* @cols: Number of columns in the keypad
|
|
* @row_shift: log2 or number of rows, rounded up
|
|
* @keymap_data: Matrix keymap data used to convert to keyscan values
|
|
* @ghost_filter: true to enable the matrix key-ghosting filter
|
|
* @valid_keys: bitmap of existing keys for each matrix column
|
|
* @old_kb_state: bitmap of keys pressed last scan
|
|
* @dev: Device pointer
|
|
* @idev: Input device
|
|
* @ec: Top level ChromeOS device to use to talk to EC
|
|
*/
|
|
struct cros_ec_keyb {
|
|
unsigned int rows;
|
|
unsigned int cols;
|
|
int row_shift;
|
|
const struct matrix_keymap_data *keymap_data;
|
|
bool ghost_filter;
|
|
uint8_t *valid_keys;
|
|
uint8_t *old_kb_state;
|
|
|
|
struct device *dev;
|
|
struct input_dev *idev;
|
|
struct cros_ec_device *ec;
|
|
};
|
|
|
|
|
|
/*
|
|
* Returns true when there is at least one combination of pressed keys that
|
|
* results in ghosting.
|
|
*/
|
|
static bool cros_ec_keyb_has_ghosting(struct cros_ec_keyb *ckdev, uint8_t *buf)
|
|
{
|
|
int col1, col2, buf1, buf2;
|
|
struct device *dev = ckdev->dev;
|
|
uint8_t *valid_keys = ckdev->valid_keys;
|
|
|
|
/*
|
|
* Ghosting happens if for any pressed key X there are other keys
|
|
* pressed both in the same row and column of X as, for instance,
|
|
* in the following diagram:
|
|
*
|
|
* . . Y . g .
|
|
* . . . . . .
|
|
* . . . . . .
|
|
* . . X . Z .
|
|
*
|
|
* In this case only X, Y, and Z are pressed, but g appears to be
|
|
* pressed too (see Wikipedia).
|
|
*/
|
|
for (col1 = 0; col1 < ckdev->cols; col1++) {
|
|
buf1 = buf[col1] & valid_keys[col1];
|
|
for (col2 = col1 + 1; col2 < ckdev->cols; col2++) {
|
|
buf2 = buf[col2] & valid_keys[col2];
|
|
if (hweight8(buf1 & buf2) > 1) {
|
|
dev_dbg(dev, "ghost found at: B[%02d]:0x%02x & B[%02d]:0x%02x",
|
|
col1, buf1, col2, buf2);
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
|
|
/*
|
|
* Compares the new keyboard state to the old one and produces key
|
|
* press/release events accordingly. The keyboard state is 13 bytes (one byte
|
|
* per column)
|
|
*/
|
|
static void cros_ec_keyb_process(struct cros_ec_keyb *ckdev,
|
|
uint8_t *kb_state, int len)
|
|
{
|
|
struct input_dev *idev = ckdev->idev;
|
|
int col, row;
|
|
int new_state;
|
|
int old_state;
|
|
int num_cols;
|
|
|
|
num_cols = len;
|
|
|
|
if (ckdev->ghost_filter && cros_ec_keyb_has_ghosting(ckdev, kb_state)) {
|
|
/*
|
|
* Simple-minded solution: ignore this state. The obvious
|
|
* improvement is to only ignore changes to keys involved in
|
|
* the ghosting, but process the other changes.
|
|
*/
|
|
dev_dbg(ckdev->dev, "ghosting found\n");
|
|
return;
|
|
}
|
|
|
|
for (col = 0; col < ckdev->cols; col++) {
|
|
for (row = 0; row < ckdev->rows; row++) {
|
|
int pos = MATRIX_SCAN_CODE(row, col, ckdev->row_shift);
|
|
const unsigned short *keycodes = idev->keycode;
|
|
|
|
new_state = kb_state[col] & (1 << row);
|
|
old_state = ckdev->old_kb_state[col] & (1 << row);
|
|
if (new_state != old_state) {
|
|
dev_dbg(ckdev->dev,
|
|
"changed: [r%d c%d]: byte %02x\n",
|
|
row, col, new_state);
|
|
|
|
input_report_key(idev, keycodes[pos],
|
|
new_state);
|
|
}
|
|
}
|
|
ckdev->old_kb_state[col] = kb_state[col];
|
|
}
|
|
input_sync(ckdev->idev);
|
|
}
|
|
|
|
static int cros_ec_keyb_get_state(struct cros_ec_keyb *ckdev, uint8_t *kb_state)
|
|
{
|
|
struct cros_ec_command msg = {
|
|
.version = 0,
|
|
.command = EC_CMD_MKBP_STATE,
|
|
.outdata = NULL,
|
|
.outsize = 0,
|
|
.indata = kb_state,
|
|
.insize = ckdev->cols,
|
|
};
|
|
|
|
return cros_ec_cmd_xfer(ckdev->ec, &msg);
|
|
}
|
|
|
|
static irqreturn_t cros_ec_keyb_irq(int irq, void *data)
|
|
{
|
|
struct cros_ec_keyb *ckdev = data;
|
|
struct cros_ec_device *ec = ckdev->ec;
|
|
int ret;
|
|
uint8_t kb_state[ckdev->cols];
|
|
|
|
if (device_may_wakeup(ec->dev))
|
|
pm_wakeup_event(ec->dev, 0);
|
|
|
|
ret = cros_ec_keyb_get_state(ckdev, kb_state);
|
|
if (ret >= 0)
|
|
cros_ec_keyb_process(ckdev, kb_state, ret);
|
|
else
|
|
dev_err(ec->dev, "failed to get keyboard state: %d\n", ret);
|
|
|
|
return IRQ_HANDLED;
|
|
}
|
|
|
|
static int cros_ec_keyb_open(struct input_dev *dev)
|
|
{
|
|
struct cros_ec_keyb *ckdev = input_get_drvdata(dev);
|
|
struct cros_ec_device *ec = ckdev->ec;
|
|
|
|
return request_threaded_irq(ec->irq, NULL, cros_ec_keyb_irq,
|
|
IRQF_TRIGGER_LOW | IRQF_ONESHOT,
|
|
"cros_ec_keyb", ckdev);
|
|
}
|
|
|
|
static void cros_ec_keyb_close(struct input_dev *dev)
|
|
{
|
|
struct cros_ec_keyb *ckdev = input_get_drvdata(dev);
|
|
struct cros_ec_device *ec = ckdev->ec;
|
|
|
|
free_irq(ec->irq, ckdev);
|
|
}
|
|
|
|
/*
|
|
* Walks keycodes flipping bit in buffer COLUMNS deep where bit is ROW. Used by
|
|
* ghosting logic to ignore NULL or virtual keys.
|
|
*/
|
|
static void cros_ec_keyb_compute_valid_keys(struct cros_ec_keyb *ckdev)
|
|
{
|
|
int row, col;
|
|
int row_shift = ckdev->row_shift;
|
|
unsigned short *keymap = ckdev->idev->keycode;
|
|
unsigned short code;
|
|
|
|
BUG_ON(ckdev->idev->keycodesize != sizeof(*keymap));
|
|
|
|
for (col = 0; col < ckdev->cols; col++) {
|
|
for (row = 0; row < ckdev->rows; row++) {
|
|
code = keymap[MATRIX_SCAN_CODE(row, col, row_shift)];
|
|
if (code && (code != KEY_BATTERY))
|
|
ckdev->valid_keys[col] |= 1 << row;
|
|
}
|
|
dev_dbg(ckdev->dev, "valid_keys[%02d] = 0x%02x\n",
|
|
col, ckdev->valid_keys[col]);
|
|
}
|
|
}
|
|
|
|
static int cros_ec_keyb_probe(struct platform_device *pdev)
|
|
{
|
|
struct cros_ec_device *ec = dev_get_drvdata(pdev->dev.parent);
|
|
struct device *dev = ec->dev;
|
|
struct cros_ec_keyb *ckdev;
|
|
struct input_dev *idev;
|
|
struct device_node *np;
|
|
int err;
|
|
|
|
np = pdev->dev.of_node;
|
|
if (!np)
|
|
return -ENODEV;
|
|
|
|
ckdev = devm_kzalloc(&pdev->dev, sizeof(*ckdev), GFP_KERNEL);
|
|
if (!ckdev)
|
|
return -ENOMEM;
|
|
err = matrix_keypad_parse_of_params(&pdev->dev, &ckdev->rows,
|
|
&ckdev->cols);
|
|
if (err)
|
|
return err;
|
|
|
|
ckdev->valid_keys = devm_kzalloc(&pdev->dev, ckdev->cols, GFP_KERNEL);
|
|
if (!ckdev->valid_keys)
|
|
return -ENOMEM;
|
|
|
|
ckdev->old_kb_state = devm_kzalloc(&pdev->dev, ckdev->cols, GFP_KERNEL);
|
|
if (!ckdev->old_kb_state)
|
|
return -ENOMEM;
|
|
|
|
idev = devm_input_allocate_device(&pdev->dev);
|
|
if (!idev)
|
|
return -ENOMEM;
|
|
|
|
if (!ec->irq) {
|
|
dev_err(dev, "no EC IRQ specified\n");
|
|
return -EINVAL;
|
|
}
|
|
|
|
ckdev->ec = ec;
|
|
ckdev->dev = dev;
|
|
dev_set_drvdata(&pdev->dev, ckdev);
|
|
|
|
idev->name = ec->ec_name;
|
|
idev->phys = ec->phys_name;
|
|
__set_bit(EV_REP, idev->evbit);
|
|
|
|
idev->id.bustype = BUS_VIRTUAL;
|
|
idev->id.version = 1;
|
|
idev->id.product = 0;
|
|
idev->dev.parent = &pdev->dev;
|
|
idev->open = cros_ec_keyb_open;
|
|
idev->close = cros_ec_keyb_close;
|
|
|
|
ckdev->ghost_filter = of_property_read_bool(np,
|
|
"google,needs-ghost-filter");
|
|
|
|
err = matrix_keypad_build_keymap(NULL, NULL, ckdev->rows, ckdev->cols,
|
|
NULL, idev);
|
|
if (err) {
|
|
dev_err(dev, "cannot build key matrix\n");
|
|
return err;
|
|
}
|
|
|
|
ckdev->row_shift = get_count_order(ckdev->cols);
|
|
|
|
input_set_capability(idev, EV_MSC, MSC_SCAN);
|
|
input_set_drvdata(idev, ckdev);
|
|
ckdev->idev = idev;
|
|
cros_ec_keyb_compute_valid_keys(ckdev);
|
|
|
|
err = input_register_device(ckdev->idev);
|
|
if (err) {
|
|
dev_err(dev, "cannot register input device\n");
|
|
return err;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
#ifdef CONFIG_PM_SLEEP
|
|
/* Clear any keys in the buffer */
|
|
static void cros_ec_keyb_clear_keyboard(struct cros_ec_keyb *ckdev)
|
|
{
|
|
uint8_t old_state[ckdev->cols];
|
|
uint8_t new_state[ckdev->cols];
|
|
unsigned long duration;
|
|
int i, ret;
|
|
|
|
/*
|
|
* Keep reading until we see that the scan state does not change.
|
|
* That indicates that we are done.
|
|
*
|
|
* Assume that the EC keyscan buffer is at most 32 deep.
|
|
*/
|
|
duration = jiffies;
|
|
ret = cros_ec_keyb_get_state(ckdev, new_state);
|
|
for (i = 1; !ret && i < 32; i++) {
|
|
memcpy(old_state, new_state, sizeof(old_state));
|
|
ret = cros_ec_keyb_get_state(ckdev, new_state);
|
|
if (0 == memcmp(old_state, new_state, sizeof(old_state)))
|
|
break;
|
|
}
|
|
duration = jiffies - duration;
|
|
dev_info(ckdev->dev, "Discarded %d keyscan(s) in %dus\n", i,
|
|
jiffies_to_usecs(duration));
|
|
}
|
|
|
|
static int cros_ec_keyb_resume(struct device *dev)
|
|
{
|
|
struct cros_ec_keyb *ckdev = dev_get_drvdata(dev);
|
|
|
|
/*
|
|
* When the EC is not a wake source, then it could not have caused the
|
|
* resume, so we clear the EC's key scan buffer. If the EC was a
|
|
* wake source (e.g. the lid is open and the user might press a key to
|
|
* wake) then the key scan buffer should be preserved.
|
|
*/
|
|
if (ckdev->ec->was_wake_device)
|
|
cros_ec_keyb_clear_keyboard(ckdev);
|
|
|
|
return 0;
|
|
}
|
|
|
|
#endif
|
|
|
|
static SIMPLE_DEV_PM_OPS(cros_ec_keyb_pm_ops, NULL, cros_ec_keyb_resume);
|
|
|
|
#ifdef CONFIG_OF
|
|
static const struct of_device_id cros_ec_keyb_of_match[] = {
|
|
{ .compatible = "google,cros-ec-keyb" },
|
|
{},
|
|
};
|
|
MODULE_DEVICE_TABLE(of, cros_ec_keyb_of_match);
|
|
#endif
|
|
|
|
static struct platform_driver cros_ec_keyb_driver = {
|
|
.probe = cros_ec_keyb_probe,
|
|
.driver = {
|
|
.name = "cros-ec-keyb",
|
|
.of_match_table = of_match_ptr(cros_ec_keyb_of_match),
|
|
.pm = &cros_ec_keyb_pm_ops,
|
|
},
|
|
};
|
|
|
|
module_platform_driver(cros_ec_keyb_driver);
|
|
|
|
MODULE_LICENSE("GPL");
|
|
MODULE_DESCRIPTION("ChromeOS EC keyboard driver");
|
|
MODULE_ALIAS("platform:cros-ec-keyb");
|