dm: input: Create a keyboard uclass

Add a uclass for keyboard input, mirroring the existing stdio methods.
This is enabled by a new CONFIG_DM_KEYBOARD option.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Marek Vasut <marex@denx.de>
Reviewed-by: Bin Meng <bmeng.cn@gmail.com>

common/usb_kbd.c

@@ -649,12 +649,6 @@ U_BOOT_DRIVER(usb_kbd) = {
 	.probe = usb_kbd_probe,
 };
 
-/* TODO(sjg@chromium.org): Move this into a common location */
-UCLASS_DRIVER(keyboard) = {
-	.id		= UCLASS_KEYBOARD,
-	.name		= "keyboard",
-};
-
 static const struct usb_device_id kbd_id_table[] = {
 	{
 		.match_flags = USB_DEVICE_ID_MATCH_INT_CLASS |

drivers/input/Kconfig

@@ -1,3 +1,12 @@
+config DM_KEYBOARD
+	bool "Enable driver model keyboard support"
+	depends on DM
+	help
+	  This adds a uclass for keyboards and implements keyboard support
+	  using driver model. The API is implemented by keyboard.h and
+	  includes methods to start/stop the device, check for available
+	  input and update LEDs if the keyboard has them.
+
 config CROS_EC_KEYB
 	bool "Enable Chrome OS EC keyboard support"
 	help

drivers/input/Makefile

@@ -5,6 +5,8 @@
 # SPDX-License-Identifier:	GPL-2.0+
 #
 
+obj-$(CONFIG_DM_KEYBOARD) += keyboard-uclass.o
+
 obj-$(CONFIG_I8042_KBD) += i8042.o
 obj-$(CONFIG_TEGRA_KEYBOARD) += tegra-kbc.o
 obj-$(CONFIG_TWL4030_INPUT) += twl4030.o

drivers/input/keyboard-uclass.c

@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2015 Google, Inc
+ *
+ * SPDX-License-Identifier:	GPL-2.0+
+ */
+
+#include <common.h>
+#include <dm.h>
+#include <keyboard.h>
+
+static int keyboard_start(struct stdio_dev *sdev)
+{
+	struct udevice *dev = sdev->priv;
+	struct keyboard_ops *ops = keyboard_get_ops(dev);
+
+	if (ops->start)
+		return ops->start(dev);
+
+	return 0;
+}
+
+static int keyboard_stop(struct stdio_dev *sdev)
+{
+	struct udevice *dev = sdev->priv;
+	struct keyboard_ops *ops = keyboard_get_ops(dev);
+
+	if (ops->stop)
+		return ops->stop(dev);
+
+	return 0;
+}
+
+static int keyboard_tstc(struct stdio_dev *sdev)
+{
+	struct udevice *dev = sdev->priv;
+	struct keyboard_priv *priv = dev_get_uclass_priv(dev);
+	struct keyboard_ops *ops = keyboard_get_ops(dev);
+
+	/* Just get input to do this for us if we can */
+	if (priv->input.dev)
+		return input_tstc(&priv->input);
+	else if (ops->tstc)
+		return ops->tstc(dev);
+
+	return -ENOSYS;
+}
+
+static int keyboard_getc(struct stdio_dev *sdev)
+{
+	struct udevice *dev = sdev->priv;
+	struct keyboard_priv *priv = dev_get_uclass_priv(dev);
+	struct keyboard_ops *ops = keyboard_get_ops(dev);
+
+	/* Just get input to do this for us if we can */
+	if (priv->input.dev)
+		return input_getc(&priv->input);
+	else if (ops->getc)
+		return ops->getc(dev);
+
+	return -ENOSYS;
+}
+
+static int keyboard_pre_probe(struct udevice *dev)
+{
+	struct keyboard_priv *priv = dev_get_uclass_priv(dev);
+	struct stdio_dev *sdev = &priv->sdev;
+	int ret;
+
+	strlcpy(sdev->name, dev->name, sizeof(sdev->name));
+	sdev->flags = DEV_FLAGS_INPUT;
+	sdev->getc = keyboard_getc;
+	sdev->tstc = keyboard_tstc;
+	sdev->start = keyboard_start;
+	sdev->stop = keyboard_stop;
+	sdev->priv = dev;
+	ret = input_init(&priv->input, 0);
+	if (ret) {
+		debug("%s: Cannot set up input, ret=%d - please add DEBUG to drivers/input/input.c to figure out the cause\n",
+		      __func__, ret);
+		return ret;
+	}
+
+	return 0;
+}
+
+UCLASS_DRIVER(keyboard) = {
+	.id		= UCLASS_KEYBOARD,
+	.name		= "keyboard",
+	.pre_probe	= keyboard_pre_probe,
+	.per_device_auto_alloc_size = sizeof(struct keyboard_priv),
+};

include/keyboard.h

@@ -1,6 +1,84 @@
 #ifndef __KEYBOARD_H
 #define __KEYBOARD_H
 
+#ifdef CONFIG_DM_KEYBOARD
+#include <input.h>
+#include <stdio_dev.h>
+
+/**
+ * struct keyboard_priv - information about a keyboard, for the uclass
+ *
+ * @sdev:	stdio device
+ * @input:	input configuration (the driver may use this if desired)
+ */
+struct keyboard_priv {
+	struct stdio_dev sdev;
+
+	/*
+	 * This is set up by the uclass but will only be used if the driver
+	 * sets input.dev to its device pointer (it is initially NULL).
+	 */
+	struct input_config input;
+};
+
+/**
+ * struct keyboard_ops - keyboard device operations
+ */
+struct keyboard_ops {
+	/**
+	 * start() - enable the keyboard ready for use
+	 *
+	 * @dev:	Device to enable
+	 * @return 0 if OK, -ve on error
+	 */
+	int (*start)(struct udevice *dev);
+
+	/**
+	 * stop() - disable the keyboard when no-longer needed
+	 *
+	 * @dev:	Device to disable
+	 * @return 0 if OK, -ve on error
+	 */
+	int (*stop)(struct udevice *dev);
+
+	/**
+	 * tstc() - check if a key is available
+	 *
+	 * @dev:	Device to check
+	 * @return 0 if no key is available, 1 if a key is available, -ve on
+	 *	   error
+	 */
+	int (*tstc)(struct udevice *dev);
+
+	/**
+	 * getc() - get a key
+	 *
+	 * TODO(sjg@chromium.org): At present this method may wait if it calls
+	 * input_getc().
+	 *
+	 * @dev:	Device to read from
+	 * @return -EAGAIN if no key is available, otherwise key value read
+	 *	   (as ASCII).
+	 */
+	int (*getc)(struct udevice *dev);
+
+	/**
+	 * update_leds() - update keyboard LEDs
+	 *
+	 * This is called when the LEDs have changed and need to be updated.
+	 * For example, if 'caps lock' is pressed then this method will be
+	 * called with the new LED value.
+	 *
+	 * @dev:	Device to update
+	 * @leds:	New LED mask (see INPUT_LED_... in input.h)
+	 */
+	int (*update_leds)(struct udevice *dev, int leds);
+};
+
+#define keyboard_get_ops(dev)	((struct keyboard_ops *)(dev)->driver->ops)
+
+#else
+
 #ifdef CONFIG_PS2MULT
 #include <ps2mult.h>
 #endif
@@ -18,5 +96,6 @@ extern int kbd_init (void);
 extern void handle_scancode(unsigned char scancode);
 extern int kbd_init_hw(void);
 extern void pckbd_leds(unsigned char leds);
+#endif /* !CONFIG_DM_KEYBOARD */
 
 #endif /* __KEYBOARD_H */