diff options
Diffstat (limited to 'drivers/input/apple_spi_kbd.c')
| -rw-r--r-- | drivers/input/apple_spi_kbd.c | 271 |
1 files changed, 271 insertions, 0 deletions
diff --git a/drivers/input/apple_spi_kbd.c b/drivers/input/apple_spi_kbd.c new file mode 100644 index 0000000000..7cf12f453a --- /dev/null +++ b/drivers/input/apple_spi_kbd.c @@ -0,0 +1,271 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2021 Mark Kettenis <kettenis@openbsd.org> + */ + +#include <common.h> +#include <dm.h> +#include <keyboard.h> +#include <spi.h> +#include <stdio_dev.h> +#include <asm-generic/gpio.h> +#include <linux/delay.h> +#include <linux/input.h> + +/* + * The Apple SPI keyboard controller implements a protocol that + * closely resembles HID Keyboard Boot protocol. The key codes are + * mapped according to the HID Keyboard/Keypad Usage Table. + */ + +/* Modifier key bits */ +#define HID_MOD_LEFTCTRL BIT(0) +#define HID_MOD_LEFTSHIFT BIT(1) +#define HID_MOD_LEFTALT BIT(2) +#define HID_MOD_LEFTGUI BIT(3) +#define HID_MOD_RIGHTCTRL BIT(4) +#define HID_MOD_RIGHTSHIFT BIT(5) +#define HID_MOD_RIGHTALT BIT(6) +#define HID_MOD_RIGHTGUI BIT(7) + +static const u8 hid_kbd_keymap[] = { + KEY_RESERVED, 0xff, 0xff, 0xff, + KEY_A, KEY_B, KEY_C, KEY_D, + KEY_E, KEY_F, KEY_G, KEY_H, + KEY_I, KEY_J, KEY_K, KEY_L, + KEY_M, KEY_N, KEY_O, KEY_P, + KEY_Q, KEY_R, KEY_S, KEY_T, + KEY_U, KEY_V, KEY_W, KEY_X, + KEY_Y, KEY_Z, KEY_1, KEY_2, + KEY_3, KEY_4, KEY_5, KEY_6, + KEY_7, KEY_8, KEY_9, KEY_0, + KEY_ENTER, KEY_ESC, KEY_BACKSPACE, KEY_TAB, + KEY_SPACE, KEY_MINUS, KEY_EQUAL, KEY_LEFTBRACE, + KEY_RIGHTBRACE, KEY_BACKSLASH, 0xff, KEY_SEMICOLON, + KEY_APOSTROPHE, KEY_GRAVE, KEY_COMMA, KEY_DOT, + KEY_SLASH, KEY_CAPSLOCK, KEY_F1, KEY_F2, + KEY_F3, KEY_F4, KEY_F5, KEY_F6, + KEY_F7, KEY_F8, KEY_F9, KEY_F10, + KEY_F11, KEY_F12, KEY_SYSRQ, KEY_SCROLLLOCK, + KEY_PAUSE, KEY_INSERT, KEY_HOME, KEY_PAGEUP, + KEY_DELETE, KEY_END, KEY_PAGEDOWN, KEY_RIGHT, + KEY_LEFT, KEY_DOWN, KEY_UP, KEY_NUMLOCK, + KEY_KPSLASH, KEY_KPASTERISK, KEY_KPMINUS, KEY_KPPLUS, + KEY_KPENTER, KEY_KP1, KEY_KP2, KEY_KP3, + KEY_KP4, KEY_KP5, KEY_KP6, KEY_KP7, + KEY_KP8, KEY_KP9, KEY_KP0, KEY_KPDOT, + KEY_BACKSLASH, KEY_COMPOSE, KEY_POWER, KEY_KPEQUAL, +}; + +/* Report ID used for keyboard input reports. */ +#define KBD_REPORTID 0x01 + +struct apple_spi_kbd_report { + u8 reportid; + u8 modifiers; + u8 reserved; + u8 keycode[6]; + u8 fn; +}; + +struct apple_spi_kbd_priv { + struct gpio_desc enable; + struct apple_spi_kbd_report old; /* previous keyboard input report */ + struct apple_spi_kbd_report new; /* current keyboard input report */ +}; + +/* Keyboard device. */ +#define KBD_DEVICE 0x01 + +/* The controller sends us fixed-size packets of 256 bytes. */ +struct apple_spi_kbd_packet { + u8 flags; +#define PACKET_READ 0x20 + u8 device; + u16 offset; + u16 remaining; + u16 len; + u8 data[246]; + u16 crc; +}; + +/* Packets contain a single variable-sized message. */ +struct apple_spi_kbd_msg { + u8 type; +#define MSG_REPORT 0x10 + u8 device; + u8 unknown; + u8 msgid; + u16 rsplen; + u16 cmdlen; + u8 data[0]; +}; + +static void apple_spi_kbd_service_modifiers(struct input_config *input) +{ + struct apple_spi_kbd_priv *priv = dev_get_priv(input->dev); + u8 new = priv->new.modifiers; + u8 old = priv->old.modifiers; + + if ((new ^ old) & HID_MOD_LEFTCTRL) + input_add_keycode(input, KEY_LEFTCTRL, + old & HID_MOD_LEFTCTRL); + if ((new ^ old) & HID_MOD_RIGHTCTRL) + input_add_keycode(input, KEY_RIGHTCTRL, + old & HID_MOD_RIGHTCTRL); + if ((new ^ old) & HID_MOD_LEFTSHIFT) + input_add_keycode(input, KEY_LEFTSHIFT, + old & HID_MOD_LEFTSHIFT); + if ((new ^ old) & HID_MOD_RIGHTSHIFT) + input_add_keycode(input, KEY_RIGHTSHIFT, + old & HID_MOD_RIGHTSHIFT); + if ((new ^ old) & HID_MOD_LEFTALT) + input_add_keycode(input, KEY_LEFTALT, + old & HID_MOD_LEFTALT); + if ((new ^ old) & HID_MOD_RIGHTALT) + input_add_keycode(input, KEY_RIGHTALT, + old & HID_MOD_RIGHTALT); + if ((new ^ old) & HID_MOD_LEFTGUI) + input_add_keycode(input, KEY_LEFTMETA, + old & HID_MOD_LEFTGUI); + if ((new ^ old) & HID_MOD_RIGHTGUI) + input_add_keycode(input, KEY_RIGHTMETA, + old & HID_MOD_RIGHTGUI); +} + +static void apple_spi_kbd_service_key(struct input_config *input, int i, + int released) +{ + struct apple_spi_kbd_priv *priv = dev_get_priv(input->dev); + u8 *new; + u8 *old; + + if (released) { + new = priv->new.keycode; + old = priv->old.keycode; + } else { + new = priv->old.keycode; + old = priv->new.keycode; + } + + if (memscan(new, old[i], sizeof(priv->new.keycode)) == + new + sizeof(priv->new.keycode) && + old[i] < ARRAY_SIZE(hid_kbd_keymap)) + input_add_keycode(input, hid_kbd_keymap[old[i]], released); +} + +static int apple_spi_kbd_check(struct input_config *input) +{ + struct udevice *dev = input->dev; + struct apple_spi_kbd_priv *priv = dev_get_priv(dev); + struct apple_spi_kbd_packet packet; + struct apple_spi_kbd_msg *msg; + struct apple_spi_kbd_report *report; + int i, ret; + + memset(&packet, 0, sizeof(packet)); + + ret = dm_spi_claim_bus(dev); + if (ret < 0) + return ret; + + /* + * The keyboard controller needs delays after asserting CS# + * and before deasserting CS#. + */ + ret = dm_spi_xfer(dev, 0, NULL, NULL, SPI_XFER_BEGIN); + if (ret < 0) + goto fail; + udelay(100); + ret = dm_spi_xfer(dev, sizeof(packet) * 8, NULL, &packet, 0); + if (ret < 0) + goto fail; + udelay(100); + ret = dm_spi_xfer(dev, 0, NULL, NULL, SPI_XFER_END); + if (ret < 0) + goto fail; + + dm_spi_release_bus(dev); + + /* + * The keyboard controller needs a delay between subsequent + * SPI transfers. + */ + udelay(250); + + msg = (struct apple_spi_kbd_msg *)packet.data; + report = (struct apple_spi_kbd_report *)msg->data; + if (packet.flags == PACKET_READ && packet.device == KBD_DEVICE && + msg->type == MSG_REPORT && msg->device == KBD_DEVICE && + msg->cmdlen == sizeof(struct apple_spi_kbd_report) && + report->reportid == KBD_REPORTID) { + memcpy(&priv->new, report, + sizeof(struct apple_spi_kbd_report)); + apple_spi_kbd_service_modifiers(input); + for (i = 0; i < sizeof(priv->new.keycode); i++) { + apple_spi_kbd_service_key(input, i, 1); + apple_spi_kbd_service_key(input, i, 0); + } + memcpy(&priv->old, &priv->new, + sizeof(struct apple_spi_kbd_report)); + return 1; + } + + return 0; + +fail: + /* + * Make sure CS# is deasserted. If this fails there is nothing + * we can do, so ignore any errors. + */ + dm_spi_xfer(dev, 0, NULL, NULL, SPI_XFER_END); + dm_spi_release_bus(dev); + return ret; +} + +static int apple_spi_kbd_probe(struct udevice *dev) +{ + struct apple_spi_kbd_priv *priv = dev_get_priv(dev); + struct keyboard_priv *uc_priv = dev_get_uclass_priv(dev); + struct stdio_dev *sdev = &uc_priv->sdev; + struct input_config *input = &uc_priv->input; + int ret; + + ret = gpio_request_by_name(dev, "spien-gpios", 0, &priv->enable, + GPIOD_IS_OUT); + if (ret < 0) + return ret; + + /* Reset the keyboard controller. */ + dm_gpio_set_value(&priv->enable, 1); + udelay(5000); + dm_gpio_set_value(&priv->enable, 0); + udelay(5000); + + /* Enable the keyboard controller. */ + dm_gpio_set_value(&priv->enable, 1); + + input->dev = dev; + input->read_keys = apple_spi_kbd_check; + input_add_tables(input, false); + strcpy(sdev->name, "spikbd"); + + return input_stdio_register(sdev); +} + +static const struct keyboard_ops apple_spi_kbd_ops = { +}; + +static const struct udevice_id apple_spi_kbd_of_match[] = { + { .compatible = "apple,spi-hid-transport" }, + { /* sentinel */ } +}; + +U_BOOT_DRIVER(apple_spi_kbd) = { + .name = "apple_spi_kbd", + .id = UCLASS_KEYBOARD, + .of_match = apple_spi_kbd_of_match, + .probe = apple_spi_kbd_probe, + .priv_auto = sizeof(struct apple_spi_kbd_priv), + .ops = &apple_spi_kbd_ops, +}; |