platform/chrome: Add Chrome OS EC userspace device interface

This patch adds a device interface to access the
Chrome OS Embedded Controller from user-space.

Signed-off-by: Bill Richardson <wfrichar@chromium.org>
Reviewed-by: Simon Glass <sjg@google.com>
Signed-off-by: Javier Martinez Canillas <javier.martinez@collabora.co.uk>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Tested-by: Gwendal Grignou <gwendal@chromium.org>
Reviewed-by: Gwendal Grignou <gwendal@chromium.org>
Signed-off-by: Olof Johansson <olof@lixom.net>

1 files changed, 47 insertions, 0 deletions

diff --git a/drivers/platform/chrome/cros_ec_dev.h b/drivers/platform/chrome/cros_ec_dev.h
new file mode 100644
index 000000000000..15c54c4c5531
--- /dev/null
+++ b/drivers/platform/chrome/cros_ec_dev.h
@@ -0,0 +1,47 @@
+/*
+ * cros_ec_dev - expose the Chrome OS Embedded Controller to userspace
+ *
+ * Copyright (C) 2014 Google, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef _CROS_EC_DEV_H_
+#define _CROS_EC_DEV_H_
+
+#include <linux/ioctl.h>
+#include <linux/types.h>
+#include <linux/mfd/cros_ec.h>
+
+#define CROS_EC_DEV_NAME "cros_ec"
+#define CROS_EC_DEV_VERSION "1.0.0"
+
+/*
+ * @offset: within EC_LPC_ADDR_MEMMAP region
+ * @bytes: number of bytes to read. zero means "read a string" (including '\0')
+ *         (at most only EC_MEMMAP_SIZE bytes can be read)
+ * @buffer: where to store the result
+ * ioctl returns the number of bytes read, negative on error
+ */
+struct cros_ec_readmem {
+	uint32_t offset;
+	uint32_t bytes;
+	uint8_t buffer[EC_MEMMAP_SIZE];
+};
+
+#define CROS_EC_DEV_IOC       0xEC
+#define CROS_EC_DEV_IOCXCMD   _IOWR(CROS_EC_DEV_IOC, 0, struct cros_ec_command)
+#define CROS_EC_DEV_IOCRDMEM  _IOWR(CROS_EC_DEV_IOC, 1, struct cros_ec_readmem)
+
+#endif /* _CROS_EC_DEV_H_ */