From 3a29355a22c0275fe864100794fee58a73175d93 Mon Sep 17 00:00:00 2001 From: Viresh Kumar Date: Thu, 19 Aug 2021 10:00:22 +0530 Subject: gpio: Add virtio-gpio driver This patch adds a new driver for Virtio based GPIO devices. This allows a guest VM running Linux to access GPIO lines provided by the host. It supports all basic operations, except interrupts for the GPIO lines. Based on the initial work posted by: "Enrico Weigelt, metux IT consult" . Reviewed-by: Linus Walleij Signed-off-by: Viresh Kumar Signed-off-by: Bartosz Golaszewski --- include/uapi/linux/virtio_gpio.h | 47 ++++++++++++++++++++++++++++++++++++++++ include/uapi/linux/virtio_ids.h | 1 + 2 files changed, 48 insertions(+) create mode 100644 include/uapi/linux/virtio_gpio.h (limited to 'include') diff --git a/include/uapi/linux/virtio_gpio.h b/include/uapi/linux/virtio_gpio.h new file mode 100644 index 000000000000..844574acf095 --- /dev/null +++ b/include/uapi/linux/virtio_gpio.h @@ -0,0 +1,47 @@ +/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */ + +#ifndef _LINUX_VIRTIO_GPIO_H +#define _LINUX_VIRTIO_GPIO_H + +#include + +/* Virtio GPIO request types */ +#define VIRTIO_GPIO_MSG_GET_NAMES 0x0001 +#define VIRTIO_GPIO_MSG_GET_DIRECTION 0x0002 +#define VIRTIO_GPIO_MSG_SET_DIRECTION 0x0003 +#define VIRTIO_GPIO_MSG_GET_VALUE 0x0004 +#define VIRTIO_GPIO_MSG_SET_VALUE 0x0005 + +/* Possible values of the status field */ +#define VIRTIO_GPIO_STATUS_OK 0x0 +#define VIRTIO_GPIO_STATUS_ERR 0x1 + +/* Direction types */ +#define VIRTIO_GPIO_DIRECTION_NONE 0x00 +#define VIRTIO_GPIO_DIRECTION_OUT 0x01 +#define VIRTIO_GPIO_DIRECTION_IN 0x02 + +struct virtio_gpio_config { + __u16 ngpio; + __u8 padding[2]; + __u32 gpio_names_size; +} __packed; + +/* Virtio GPIO Request / Response */ +struct virtio_gpio_request { + __u16 type; + __u16 gpio; + __u32 value; +}; + +struct virtio_gpio_response { + __u8 status; + __u8 value; +}; + +struct virtio_gpio_response_get_names { + __u8 status; + __u8 value[]; +}; + +#endif /* _LINUX_VIRTIO_GPIO_H */ diff --git a/include/uapi/linux/virtio_ids.h b/include/uapi/linux/virtio_ids.h index 70a8057ad4bb..e04fa2bfc0eb 100644 --- a/include/uapi/linux/virtio_ids.h +++ b/include/uapi/linux/virtio_ids.h @@ -56,6 +56,7 @@ #define VIRTIO_ID_PMEM 27 /* virtio pmem */ #define VIRTIO_ID_MAC80211_HWSIM 29 /* virtio mac80211-hwsim */ #define VIRTIO_ID_BT 40 /* virtio bluetooth */ +#define VIRTIO_ID_GPIO 41 /* virtio gpio */ /* * Virtio Transitional IDs -- cgit