Initial import

1 files changed, 201 insertions, 0 deletions

diff --git a/include/linux/mfd/cros_ec.h b/include/linux/mfd/cros_ec.h
new file mode 100644
index 000000000..324a34683
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+++ b/include/linux/mfd/cros_ec.h
@@ -0,0 +1,201 @@
+/*
+ * ChromeOS EC multi-function device
+ *
+ * Copyright (C) 2012 Google, Inc
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * 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.
+ */
+
+#ifndef __LINUX_MFD_CROS_EC_H
+#define __LINUX_MFD_CROS_EC_H
+
+#include <linux/cdev.h>
+#include <linux/notifier.h>
+#include <linux/mfd/cros_ec_commands.h>
+#include <linux/mutex.h>
+
+/*
+ * Command interface between EC and AP, for LPC, I2C and SPI interfaces.
+ */
+enum {
+	EC_MSG_TX_HEADER_BYTES	= 3,
+	EC_MSG_TX_TRAILER_BYTES	= 1,
+	EC_MSG_TX_PROTO_BYTES	= EC_MSG_TX_HEADER_BYTES +
+					EC_MSG_TX_TRAILER_BYTES,
+	EC_MSG_RX_PROTO_BYTES	= 3,
+
+	/* Max length of messages */
+	EC_MSG_BYTES		= EC_PROTO2_MAX_PARAM_SIZE +
+					EC_MSG_TX_PROTO_BYTES,
+};
+
+/*
+ * @version: Command version number (often 0)
+ * @command: Command to send (EC_CMD_...)
+ * @outsize: Outgoing length in bytes
+ * @insize: Max number of bytes to accept from EC
+ * @result: EC's response to the command (separate from communication failure)
+ * @outdata: Outgoing data to EC
+ * @indata: Where to put the incoming data from EC
+ */
+struct cros_ec_command {
+	uint32_t version;
+	uint32_t command;
+	uint32_t outsize;
+	uint32_t insize;
+	uint32_t result;
+	uint8_t outdata[EC_PROTO2_MAX_PARAM_SIZE];
+	uint8_t indata[EC_PROTO2_MAX_PARAM_SIZE];
+};
+
+/**
+ * struct cros_ec_device - Information about a ChromeOS EC device
+ *
+ * @ec_name: name of EC device (e.g. 'chromeos-ec')
+ * @phys_name: name of physical comms layer (e.g. 'i2c-4')
+ * @dev: Device pointer for physical comms device
+ * @vdev: Device pointer for virtual comms device
+ * @cdev: Character device structure for virtual comms device
+ * @was_wake_device: true if this device was set to wake the system from
+ * sleep at the last suspend
+ * @cmd_readmem: direct read of the EC memory-mapped region, if supported
+ *     @offset is within EC_LPC_ADDR_MEMMAP region.
+ *     @bytes: number of bytes to read. zero means "read a string" (including
+ *     the trailing '\0'). At most only EC_MEMMAP_SIZE bytes can be read.
+ *     Caller must ensure that the buffer is large enough for the result when
+ *     reading a string.
+ *
+ * @priv: Private data
+ * @irq: Interrupt to use
+ * @din: input buffer (for data from EC)
+ * @dout: output buffer (for data to EC)
+ * \note
+ * These two buffers will always be dword-aligned and include enough
+ * space for up to 7 word-alignment bytes also, so we can ensure that
+ * the body of the message is always dword-aligned (64-bit).
+ * We use this alignment to keep ARM and x86 happy. Probably word
+ * alignment would be OK, there might be a small performance advantage
+ * to using dword.
+ * @din_size: size of din buffer to allocate (zero to use static din)
+ * @dout_size: size of dout buffer to allocate (zero to use static dout)
+ * @parent: pointer to parent device (e.g. i2c or spi device)
+ * @wake_enabled: true if this device can wake the system from sleep
+ * @cmd_xfer: send command to EC and get response
+ *     Returns the number of bytes received if the communication succeeded, but
+ *     that doesn't mean the EC was happy with the command. The caller
+ *     should check msg.result for the EC's result code.
+ * @lock: one transaction at a time
+ */
+struct cros_ec_device {
+
+	/* These are used by other drivers that want to talk to the EC */
+	const char *ec_name;
+	const char *phys_name;
+	struct device *dev;
+	struct device *vdev;
+	struct cdev cdev;
+	bool was_wake_device;
+	struct class *cros_class;
+	int (*cmd_readmem)(struct cros_ec_device *ec, unsigned int offset,
+			   unsigned int bytes, void *dest);
+
+	/* These are used to implement the platform-specific interface */
+	void *priv;
+	int irq;
+	uint8_t *din;
+	uint8_t *dout;
+	int din_size;
+	int dout_size;
+	struct device *parent;
+	bool wake_enabled;
+	int (*cmd_xfer)(struct cros_ec_device *ec,
+			struct cros_ec_command *msg);
+	struct mutex lock;
+};
+
+/**
+ * cros_ec_suspend - Handle a suspend operation for the ChromeOS EC device
+ *
+ * This can be called by drivers to handle a suspend event.
+ *
+ * ec_dev: Device to suspend
+ * @return 0 if ok, -ve on error
+ */
+int cros_ec_suspend(struct cros_ec_device *ec_dev);
+
+/**
+ * cros_ec_resume - Handle a resume operation for the ChromeOS EC device
+ *
+ * This can be called by drivers to handle a resume event.
+ *
+ * @ec_dev: Device to resume
+ * @return 0 if ok, -ve on error
+ */
+int cros_ec_resume(struct cros_ec_device *ec_dev);
+
+/**
+ * cros_ec_prepare_tx - Prepare an outgoing message in the output buffer
+ *
+ * This is intended to be used by all ChromeOS EC drivers, but at present
+ * only SPI uses it. Once LPC uses the same protocol it can start using it.
+ * I2C could use it now, with a refactor of the existing code.
+ *
+ * @ec_dev: Device to register
+ * @msg: Message to write
+ */
+int cros_ec_prepare_tx(struct cros_ec_device *ec_dev,
+		       struct cros_ec_command *msg);
+
+/**
+ * cros_ec_check_result - Check ec_msg->result
+ *
+ * This is used by ChromeOS EC drivers to check the ec_msg->result for
+ * errors and to warn about them.
+ *
+ * @ec_dev: EC device
+ * @msg: Message to check
+ */
+int cros_ec_check_result(struct cros_ec_device *ec_dev,
+			 struct cros_ec_command *msg);
+
+/**
+ * cros_ec_cmd_xfer - Send a command to the ChromeOS EC
+ *
+ * Call this to send a command to the ChromeOS EC.  This should be used
+ * instead of calling the EC's cmd_xfer() callback directly.
+ *
+ * @ec_dev: EC device
+ * @msg: Message to write
+ */
+int cros_ec_cmd_xfer(struct cros_ec_device *ec_dev,
+		     struct cros_ec_command *msg);
+
+/**
+ * cros_ec_remove - Remove a ChromeOS EC
+ *
+ * Call this to deregister a ChromeOS EC, then clean up any private data.
+ *
+ * @ec_dev: Device to register
+ * @return 0 if ok, -ve on error
+ */
+int cros_ec_remove(struct cros_ec_device *ec_dev);
+
+/**
+ * cros_ec_register - Register a new ChromeOS EC, using the provided info
+ *
+ * Before calling this, allocate a pointer to a new device and then fill
+ * in all the fields up to the --private-- marker.
+ *
+ * @ec_dev: Device to register
+ * @return 0 if ok, -ve on error
+ */
+int cros_ec_register(struct cros_ec_device *ec_dev);
+
+#endif /* __LINUX_MFD_CROS_EC_H */