ratp: implement support for GPIO commands

Introduce three new RATP commands that allow getting and setting GPIO
values as well as configuring the direction of the GPIO pins.

Signed-off-by: Aleksander Morgado <aleksander@aleksander.es>
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>

1 files changed, 144 insertions, 0 deletions

diff --git a/common/ratp/gpio.c b/common/ratp/gpio.c
new file mode 100644
index 0000000000..d2c527a40c
--- /dev/null
+++ b/common/ratp/gpio.c
@@ -0,0 +1,144 @@
+/*
+ * Copyright (c) 2018 Sascha Hauer <s.hauer@pengutronix.de>, Pengutronix
+ * Copyright (c) 2018 Zodiac Inflight Innovations
+ *
+ * See file CREDITS for list of people who contributed to this
+ * project.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#define pr_fmt(fmt) "barebox-ratp: gpio: " fmt
+
+#include <common.h>
+#include <ratp_bb.h>
+#include <malloc.h>
+#include <environment.h>
+#include <gpio.h>
+#include <errno.h>
+
+struct ratp_bb_gpio_get_value_request {
+	struct ratp_bb header;
+	uint32_t       gpio;
+} __packed;
+
+struct ratp_bb_gpio_get_value_response {
+	struct ratp_bb header;
+	uint8_t        value;
+} __packed;
+
+static int ratp_cmd_gpio_get_value(const struct ratp_bb *req, int req_len,
+				   struct ratp_bb **rsp, int *rsp_len)
+{
+	struct ratp_bb_gpio_get_value_request *gpio_req = (struct ratp_bb_gpio_get_value_request *)req;
+	struct ratp_bb_gpio_get_value_response *gpio_rsp;
+	int gpio_rsp_len;
+
+	if (req_len < sizeof(*gpio_req)) {
+		pr_err("get value request ignored: size mismatch (%d < %zu)\n", req_len, sizeof(*gpio_req));
+		return 2;
+	}
+
+	gpio_rsp_len = sizeof(struct ratp_bb_gpio_get_value_response);
+	gpio_rsp = xzalloc(gpio_rsp_len);
+	gpio_rsp->header.type = cpu_to_be16(BB_RATP_TYPE_GPIO_GET_VALUE_RETURN);
+	gpio_rsp->value = !!gpio_get_value(be32_to_cpu(gpio_req->gpio));
+
+	*rsp_len = gpio_rsp_len;
+	*rsp = (struct ratp_bb *)gpio_rsp;
+	return 0;
+}
+
+BAREBOX_RATP_CMD_START(GPIO_GET_VALUE)
+	.request_id = BB_RATP_TYPE_GPIO_GET_VALUE,
+	.response_id = BB_RATP_TYPE_GPIO_GET_VALUE_RETURN,
+	.cmd = ratp_cmd_gpio_get_value
+BAREBOX_RATP_CMD_END
+
+
+struct ratp_bb_gpio_set_value_request {
+	struct ratp_bb header;
+	uint32_t       gpio;
+	uint8_t        value;
+} __packed;
+
+static int ratp_cmd_gpio_set_value(const struct ratp_bb *req, int req_len,
+				   struct ratp_bb **rsp, int *rsp_len)
+{
+	struct ratp_bb_gpio_set_value_request *gpio_req = (struct ratp_bb_gpio_set_value_request *)req;
+
+	if (req_len < sizeof(*gpio_req)) {
+		pr_err("set value request ignored: size mismatch (%d < %zu)\n", req_len, sizeof(*gpio_req));
+		return 2;
+	}
+
+	gpio_set_value(be32_to_cpu(gpio_req->gpio), gpio_req->value);
+
+	*rsp_len = sizeof(struct ratp_bb);
+	*rsp = xzalloc(*rsp_len);
+	(*rsp)->type = cpu_to_be16(BB_RATP_TYPE_GPIO_SET_VALUE_RETURN);
+	return 0;
+}
+
+BAREBOX_RATP_CMD_START(GPIO_SET_VALUE)
+	.request_id = BB_RATP_TYPE_GPIO_SET_VALUE,
+	.response_id = BB_RATP_TYPE_GPIO_SET_VALUE_RETURN,
+	.cmd = ratp_cmd_gpio_set_value
+BAREBOX_RATP_CMD_END
+
+
+struct ratp_bb_gpio_set_direction_request {
+	struct ratp_bb header;
+	uint32_t       gpio;
+	uint8_t        direction; /* 0: input, 1: output */
+	uint8_t        value;     /* applicable only if direction output */
+} __packed;
+
+struct ratp_bb_gpio_set_direction_response {
+	struct ratp_bb header;
+	uint32_t       errno;
+} __packed;
+
+static int ratp_cmd_gpio_set_direction(const struct ratp_bb *req, int req_len,
+				       struct ratp_bb **rsp, int *rsp_len)
+{
+	struct ratp_bb_gpio_set_direction_request *gpio_req = (struct ratp_bb_gpio_set_direction_request *)req;
+	struct ratp_bb_gpio_set_direction_response *gpio_rsp;
+	int gpio_rsp_len;
+	uint32_t gpio;
+	int ret;
+
+	if (req_len < sizeof(*gpio_req)) {
+		pr_err("set direction request ignored: size mismatch (%d < %zu)\n", req_len, sizeof(*gpio_req));
+		return 2;
+	}
+
+	gpio = be32_to_cpu(gpio_req->gpio);
+	if (gpio_req->direction)
+		ret = gpio_direction_output(gpio, gpio_req->value);
+	else
+		ret = gpio_direction_input(gpio);
+
+	gpio_rsp_len = sizeof(struct ratp_bb_gpio_set_direction_response);
+	gpio_rsp = xzalloc(gpio_rsp_len);
+	gpio_rsp->header.type = cpu_to_be16(BB_RATP_TYPE_GPIO_SET_DIRECTION_RETURN);
+	gpio_rsp->errno = (ret == 0 ? 0 : EIO);
+
+	*rsp_len = gpio_rsp_len;
+	*rsp = (struct ratp_bb *)gpio_rsp;
+	return 0;
+}
+
+BAREBOX_RATP_CMD_START(GPIO_SET_DIRECTION)
+	.request_id = BB_RATP_TYPE_GPIO_SET_DIRECTION,
+	.response_id = BB_RATP_TYPE_GPIO_SET_DIRECTION_RETURN,
+	.cmd = ratp_cmd_gpio_set_direction
+BAREBOX_RATP_CMD_END