Add a new uclass for button that implements two functions: - button_get_by_label - button_get_status
Reviewed-by: Simon Glass sjg@chromium.org Signed-off-by: Philippe Reynes philippe.reynes@softathome.com ---
Changelog: v2: - re-order include - use uclass_id_foreach_dev - add comments to enum button_state_t
drivers/Kconfig | 2 ++ drivers/Makefile | 1 + drivers/button/Kconfig | 12 +++++++++ drivers/button/Makefile | 5 ++++ drivers/button/button-uclass.c | 43 ++++++++++++++++++++++++++++++ include/button.h | 59 ++++++++++++++++++++++++++++++++++++++++++ include/dm/uclass-id.h | 1 + 7 files changed, 123 insertions(+) create mode 100644 drivers/button/Kconfig create mode 100644 drivers/button/Makefile create mode 100644 drivers/button/button-uclass.c create mode 100644 include/button.h
diff --git a/drivers/Kconfig b/drivers/Kconfig index e34a227..3cb05aa 100644 --- a/drivers/Kconfig +++ b/drivers/Kconfig @@ -14,6 +14,8 @@ source "drivers/block/Kconfig"
source "drivers/bootcount/Kconfig"
+source "drivers/button/Kconfig" + source "drivers/cache/Kconfig"
source "drivers/clk/Kconfig" diff --git a/drivers/Makefile b/drivers/Makefile index 94e8c5d..727a713 100644 --- a/drivers/Makefile +++ b/drivers/Makefile @@ -1,5 +1,6 @@ # SPDX-License-Identifier: GPL-2.0+
+obj-$(CONFIG_$(SPL_TPL_)BUTTON) += button/ obj-$(CONFIG_$(SPL_TPL_)CACHE) += cache/ obj-$(CONFIG_$(SPL_TPL_)CLK) += clk/ obj-$(CONFIG_$(SPL_TPL_)DM) += core/ diff --git a/drivers/button/Kconfig b/drivers/button/Kconfig new file mode 100644 index 0000000..8301858 --- /dev/null +++ b/drivers/button/Kconfig @@ -0,0 +1,12 @@ +menu "Button Support" + +config BUTTON + bool "Enable button support" + depends on DM + help + Many boards have buttons which can be used to change behaviour (reset, ...). + U-Boot provides a uclass API to implement this feature. Button drivers + can provide access to board-specific buttons. Use of the device tree + for configuration is encouraged. + +endmenu diff --git a/drivers/button/Makefile b/drivers/button/Makefile new file mode 100644 index 0000000..0b4c128 --- /dev/null +++ b/drivers/button/Makefile @@ -0,0 +1,5 @@ +# SPDX-License-Identifier: GPL-2.0+ +# +# Copyright (C) 2020 Philippe Reynes philippe.reynes@softathome.com + +obj-$(CONFIG_BUTTON) += button-uclass.o diff --git a/drivers/button/button-uclass.c b/drivers/button/button-uclass.c new file mode 100644 index 0000000..1c742c2 --- /dev/null +++ b/drivers/button/button-uclass.c @@ -0,0 +1,43 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright (C) 2020 Philippe Reynes philippe.reynes@softathome.com + * + * Based on led-uclass.c + */ + +#include <common.h> +#include <button.h> +#include <dm.h> +#include <dm/uclass-internal.h> + +int button_get_by_label(const char *label, struct udevice **devp) +{ + struct udevice *dev; + struct uclass *uc; + + uclass_id_foreach_dev(UCLASS_BUTTON, dev, uc) { + struct button_uc_plat *uc_plat = dev_get_uclass_platdata(dev); + + /* Ignore the top-level button node */ + if (uc_plat->label && !strcmp(label, uc_plat->label)) + return uclass_get_device_tail(dev, 0, devp); + } + + return -ENODEV; +} + +enum button_state_t button_get_state(struct udevice *dev) +{ + struct button_ops *ops = button_get_ops(dev); + + if (!ops->get_state) + return -ENOSYS; + + return ops->get_state(dev); +} + +UCLASS_DRIVER(button) = { + .id = UCLASS_BUTTON, + .name = "button", + .per_device_platdata_auto_alloc_size = sizeof(struct button_uc_plat), +}; diff --git a/include/button.h b/include/button.h new file mode 100644 index 0000000..688b63b --- /dev/null +++ b/include/button.h @@ -0,0 +1,59 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright (C) 2020 Philippe Reynes philippe.reynes@softathome.com + */ + +#ifndef __BUTTON_H +#define __BUTTON_H + +/** + * struct button_uc_plat - Platform data the uclass stores about each device + * + * @label: Button label + */ +struct button_uc_plat { + const char *label; +}; + +/** + * enum button_state_t - State used for button + * - BUTTON_OFF - Button is not pressed + * - BUTTON_ON - Button is pressed + * - BUTTON_COUNT - Number of button state + */ +enum button_state_t { + BUTTON_OFF = 0, + BUTTON_ON = 1, + BUTTON_COUNT, +}; + +struct button_ops { + /** + * get_state() - get the state of a button + * + * @dev: button device to change + * @return button state button_state_t, or -ve on error + */ + enum button_state_t (*get_state)(struct udevice *dev); +}; + +#define button_get_ops(dev) ((struct button_ops *)(dev)->driver->ops) + +/** + * button_get_by_label() - Find a button device by label + * + * @label: button label to look up + * @devp: Returns the associated device, if found + * @return 0 if found, -ENODEV if not found, other -ve on error + */ +int button_get_by_label(const char *label, struct udevice **devp); + +/** + * button_get_state() - get the state of a button + * + * @dev: button device to change + * @return button state button_state_t, or -ve on error + */ +enum button_state_t button_get_state(struct udevice *dev); + +#endif diff --git a/include/dm/uclass-id.h b/include/dm/uclass-id.h index 7837d45..85c7149 100644 --- a/include/dm/uclass-id.h +++ b/include/dm/uclass-id.h @@ -38,6 +38,7 @@ enum uclass_id { UCLASS_BLK, /* Block device */ UCLASS_BOARD, /* Device information from hardware */ UCLASS_BOOTCOUNT, /* Bootcount backing store */ + UCLASS_BUTTON, /* Button */ UCLASS_CACHE, /* Cache controller */ UCLASS_CLK, /* Clock source, e.g. used by peripherals */ UCLASS_CPU, /* CPU, typically part of an SoC */