X-Git-Url: https://git.karo-electronics.de/?a=blobdiff_plain;f=drivers%2Finput%2Fcros_ec_keyb.c;fp=drivers%2Finput%2Fcros_ec_keyb.c;h=e8dac237a995c0f492d3299921cc6f4fbbaf0f80;hb=5e62c5c013a717c5afd3397f7f4c823f66f04daf;hp=0000000000000000000000000000000000000000;hpb=e1b6c5e43bfba97f46fdb57724405ba916cec3b4;p=karo-tx-uboot.git diff --git a/drivers/input/cros_ec_keyb.c b/drivers/input/cros_ec_keyb.c new file mode 100644 index 0000000000..e8dac237a9 --- /dev/null +++ b/drivers/input/cros_ec_keyb.c @@ -0,0 +1,246 @@ +/* + * Chromium OS Matrix Keyboard + * + * Copyright (c) 2012 The Chromium OS Authors. + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include +#include +#include +#include +#include +#include + +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); +}