--- /dev/null
+CROS_EC Keyboard
+
+The CROS_EC (Matrix Keyboard Protocol) allows communcation with a secondary
+micro used for keyboard, and possible other features.
+
+The CROS_EC keyboard uses this protocol to receive key scans and produce input
+in U-Boot.
+
+Required properties :
+- compatible : "google,cros-ec-keyb"
+- google,key-rows : Number of key rows
+- google,key-columns : Number of key columns
+
+Optional properties, in addition to those specified by the shared
+matrix-keyboard bindings:
+
+- linux,fn-keymap: a second keymap, same specification as the
+ matrix-keyboard-controller spec but to be used when the KEY_FN modifier
+ key is pressed.
+- google,repeat-delay-ms : delay in milliseconds before repeat starts
+- google,repeat-rate-ms : delay between each subsequent key press
+- google,ghost-filter : enable ghost filtering for this device
+
+Example, taken from daisy:
+
+cros-ec-keyb {
+ compatible = "google,cros-ec-keyb";
+ google,key-rows = <8>;
+ google,key-columns = <13>;
+ google,ghost-filter;
+ google,repeat-delay-ms = <240>;
+ google,repeat-rate-ms = <30>;
+ /*
+ * Keymap entries take the form of 0xRRCCKKKK where
+ * RR=Row CC=Column KKKK=Key Code
+ * The values below are for a US keyboard layout and
+ * are taken from the Linux driver. Note that the
+ * 102ND key is not used for US keyboards.
+ */
+ linux,keymap = <
+ /* CAPSLCK F1 B F10 */
+ 0x0001003a 0x0002003c 0x00030030 0x00040044
+ /* N = R_ALT ESC */
+ 0x00060031 0x0008000d 0x000a0064 0x01010001
+ /* F4 G F7 H */
+ 0x0102003e 0x01030022 0x01040041 0x01060023
+ /* ' F9 BKSPACE L_CTRL */
+ 0x01080028 0x01090043 0x010b000e 0x0200001d
+ /* TAB F3 T F6 */
+ 0x0201000f 0x0202003d 0x02030014 0x02040040
+ /* ] Y 102ND [ */
+ 0x0205001b 0x02060015 0x02070056 0x0208001a
+ /* F8 GRAVE F2 5 */
+ 0x02090042 0x03010029 0x0302003c 0x03030006
+ /* F5 6 - \ */
+ 0x0304003f 0x03060007 0x0308000c 0x030b002b
+ /* R_CTRL A D F */
+ 0x04000061 0x0401001e 0x04020020 0x04030021
+ /* S K J ; */
+ 0x0404001f 0x04050025 0x04060024 0x04080027
+ /* L ENTER Z C */
+ 0x04090026 0x040b001c 0x0501002c 0x0502002e
+ /* V X , M */
+ 0x0503002f 0x0504002d 0x05050033 0x05060032
+ /* L_SHIFT / . SPACE */
+ 0x0507002a 0x05080035 0x05090034 0x050B0039
+ /* 1 3 4 2 */
+ 0x06010002 0x06020004 0x06030005 0x06040003
+ /* 8 7 0 9 */
+ 0x06050009 0x06060008 0x0608000b 0x0609000a
+ /* L_ALT DOWN RIGHT Q */
+ 0x060a0038 0x060b006c 0x060c006a 0x07010010
+ /* E R W I */
+ 0x07020012 0x07030013 0x07040011 0x07050017
+ /* U R_SHIFT P O */
+ 0x07060016 0x07070036 0x07080019 0x07090018
+ /* UP LEFT */
+ 0x070b0067 0x070c0069>;
+};
--- /dev/null
+/*
+ * Chromium OS Matrix Keyboard
+ *
+ * Copyright (c) 2012 The Chromium OS Authors.
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of
+ * the License, or (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
+ * MA 02111-1307 USA
+ */
+
+#include <common.h>
+#include <cros_ec.h>
+#include <fdtdec.h>
+#include <input.h>
+#include <key_matrix.h>
+#include <stdio_dev.h>
+
+DECLARE_GLOBAL_DATA_PTR;
+
+enum {
+ KBC_MAX_KEYS = 8, /* Maximum keys held down at once */
+};
+
+static struct keyb {
+ struct cros_ec_dev *dev; /* The CROS_EC device */
+ struct input_config input; /* The input layer */
+ struct key_matrix matrix; /* The key matrix layer */
+ int key_rows; /* Number of keyboard rows */
+ int key_cols; /* Number of keyboard columns */
+ unsigned int repeat_delay_ms; /* Time before autorepeat starts */
+ unsigned int repeat_rate_ms; /* Autorepeat rate in ms */
+ int ghost_filter; /* 1 to enable ghost filter, else 0 */
+ int inited; /* 1 if keyboard is ready */
+} config;
+
+
+/**
+ * Check the keyboard controller and return a list of key matrix positions
+ * for which a key is pressed
+ *
+ * @param config Keyboard config
+ * @param keys List of keys that we have detected
+ * @param max_count Maximum number of keys to return
+ * @return number of pressed keys, 0 for none
+ */
+static int check_for_keys(struct keyb *config,
+ struct key_matrix_key *keys, int max_count)
+{
+ struct key_matrix_key *key;
+ struct mbkp_keyscan scan;
+ unsigned int row, col, bit, data;
+ int num_keys;
+
+ if (cros_ec_scan_keyboard(config->dev, &scan)) {
+ debug("%s: keyboard scan failed\n", __func__);
+ return -1;
+ }
+
+ for (col = num_keys = bit = 0; col < config->matrix.num_cols;
+ col++) {
+ for (row = 0; row < config->matrix.num_rows; row++) {
+ unsigned int mask = 1 << (bit & 7);
+
+ data = scan.data[bit / 8];
+ if ((data & mask) && num_keys < max_count) {
+ key = keys + num_keys++;
+ key->row = row;
+ key->col = col;
+ key->valid = 1;
+ }
+ bit++;
+ }
+ }
+
+ return num_keys;
+}
+
+/**
+ * Test if keys are available to be read
+ *
+ * @return 0 if no keys available, 1 if keys are available
+ */
+static int kbd_tstc(void)
+{
+ /* Just get input to do this for us */
+ return config.inited ? input_tstc(&config.input) : 0;
+}
+
+/**
+ * Read a key
+ *
+ * @return ASCII key code, or 0 if no key, or -1 if error
+ */
+static int kbd_getc(void)
+{
+ /* Just get input to do this for us */
+ return config.inited ? input_getc(&config.input) : 0;
+}
+
+/**
+ * Check the keyboard, and send any keys that are pressed.
+ *
+ * This is called by input_tstc() and input_getc() when they need more
+ * characters
+ *
+ * @param input Input configuration
+ * @return 1, to indicate that we have something to look at
+ */
+int cros_ec_kbc_check(struct input_config *input)
+{
+ static struct key_matrix_key last_keys[KBC_MAX_KEYS];
+ static int last_num_keys;
+ struct key_matrix_key keys[KBC_MAX_KEYS];
+ int keycodes[KBC_MAX_KEYS];
+ int num_keys, num_keycodes;
+ int irq_pending, sent;
+
+ /*
+ * Loop until the EC has no more keyscan records, or we have
+ * received at least one character. This means we know that tstc()
+ * will always return non-zero if keys have been pressed.
+ *
+ * Without this loop, a key release (which generates no new ascii
+ * characters) will cause us to exit this function, and just tstc()
+ * may return 0 before all keys have been read from the EC.
+ */
+ do {
+ irq_pending = cros_ec_interrupt_pending(config.dev);
+ if (irq_pending) {
+ num_keys = check_for_keys(&config, keys, KBC_MAX_KEYS);
+ last_num_keys = num_keys;
+ memcpy(last_keys, keys, sizeof(keys));
+ } else {
+ /*
+ * EC doesn't want to be asked, so use keys from last
+ * time.
+ */
+ num_keys = last_num_keys;
+ memcpy(keys, last_keys, sizeof(keys));
+ }
+
+ if (num_keys < 0)
+ return -1;
+ num_keycodes = key_matrix_decode(&config.matrix, keys,
+ num_keys, keycodes, KBC_MAX_KEYS);
+ sent = input_send_keycodes(input, keycodes, num_keycodes);
+ } while (irq_pending && !sent);
+
+ return 1;
+}
+
+/**
+ * Decode MBKP keyboard details from the device tree
+ *
+ * @param blob Device tree blob
+ * @param node Node to decode from
+ * @param config Configuration data read from fdt
+ * @return 0 if ok, -1 on error
+ */
+static int cros_ec_keyb_decode_fdt(const void *blob, int node,
+ struct keyb *config)
+{
+ /*
+ * Get keyboard rows and columns - at present we are limited to
+ * 8 columns by the protocol (one byte per row scan)
+ */
+ config->key_rows = fdtdec_get_int(blob, node, "google,key-rows", 0);
+ config->key_cols = fdtdec_get_int(blob, node, "google,key-columns", 0);
+ if (!config->key_rows || !config->key_cols ||
+ config->key_rows * config->key_cols / 8
+ > CROS_EC_KEYSCAN_COLS) {
+ debug("%s: Invalid key matrix size %d x %d\n", __func__,
+ config->key_rows, config->key_cols);
+ return -1;
+ }
+ config->repeat_delay_ms = fdtdec_get_int(blob, node,
+ "google,repeat-delay-ms", 0);
+ config->repeat_rate_ms = fdtdec_get_int(blob, node,
+ "google,repeat-rate-ms", 0);
+ config->ghost_filter = fdtdec_get_bool(blob, node,
+ "google,ghost-filter");
+ return 0;
+}
+
+/**
+ * Set up the keyboard. This is called by the stdio device handler.
+ *
+ * We want to do this init when the keyboard is actually used rather than
+ * at start-up, since keyboard input may not currently be selected.
+ *
+ * @return 0 if ok, -1 on error
+ */
+static int cros_ec_init_keyboard(void)
+{
+ const void *blob = gd->fdt_blob;
+ int node;
+
+ config.dev = board_get_cros_ec_dev();
+ if (!config.dev) {
+ debug("%s: no cros_ec device: cannot init keyboard\n",
+ __func__);
+ return -1;
+ }
+ node = fdtdec_next_compatible(blob, 0, COMPAT_GOOGLE_CROS_EC_KEYB);
+ if (node < 0) {
+ debug("%s: Node not found\n", __func__);
+ return -1;
+ }
+ if (cros_ec_keyb_decode_fdt(blob, node, &config))
+ return -1;
+ input_set_delays(&config.input, config.repeat_delay_ms,
+ config.repeat_rate_ms);
+ if (key_matrix_init(&config.matrix, config.key_rows,
+ config.key_cols, config.ghost_filter)) {
+ debug("%s: cannot init key matrix\n", __func__);
+ return -1;
+ }
+ if (key_matrix_decode_fdt(&config.matrix, gd->fdt_blob, node)) {
+ debug("%s: Could not decode key matrix from fdt\n", __func__);
+ return -1;
+ }
+ config.inited = 1;
+ debug("%s: Matrix keyboard %dx%d ready\n", __func__, config.key_rows,
+ config.key_cols);
+
+ return 0;
+}
+
+int drv_keyboard_init(void)
+{
+ struct stdio_dev dev;
+
+ if (input_init(&config.input, 0)) {
+ debug("%s: Cannot set up input\n", __func__);
+ return -1;
+ }
+ config.input.read_keys = cros_ec_kbc_check;
+
+ memset(&dev, '\0', sizeof(dev));
+ strcpy(dev.name, "cros-ec-keyb");
+ dev.flags = DEV_FLAGS_INPUT | DEV_FLAGS_SYSTEM;
+ dev.getc = kbd_getc;
+ dev.tstc = kbd_tstc;
+ dev.start = cros_ec_init_keyboard;
+
+ /* Register the device. cros_ec_init_keyboard() will be called soon */
+ return input_stdio_register(&dev);
+}
projects / oweals / u-boot.git / commitdiff