HSI: cmt_speech: Add cmt-speech driver

Introduces the cmt-speech driver, which implements
a character device interface for transferring speech
data frames over HSI/SSI.

The driver is used to exchange voice/speech data between
the Nokia N900/N950/N9's modem and its cpu.
Signed-off-by: Kai Vehmanen <kai.vehmanen@nokia.com>
Signed-off-by: Carlos Chinea <carlos.chinea@nokia.com>
Signed-off-by: Joni Lapilainen <joni.lapilainen@gmail.com>

Since the original driver has been written for 2.6.28 some
build fixes and general cleanups have been added by me:

 * fix build for 4.0 kernel
 * replace GFP_ATOMIC with GFP_KERNEL in cs_alloc_cmds()
 * add sanity check for CS_SET_WAKELINE ioctl
 * cleanup driver initialisation
 * rename driver to cmt-speech to be consistent with
   ssi-protocol driver
 * move cs-protocol.h to include/uapi/linux/hsi, since
   it describes a userspace API
 * replace hardcoded channels numbers with values provided
   via the HSI framework (e.g. coming from DT)
Acked-by: Aaro Koskinen <aaro.koskinen@iki.fi>
Tested-by: Pavel Machek <pavel@ucw.cz>
Signed-off-by: Sebastian Reichel <sre@kernel.org>

drivers/hsi/clients/Kconfig

@@ -13,6 +13,16 @@ config NOKIA_MODEM
 
 	If unsure, say N.
 
+config CMT_SPEECH
+	tristate "CMT speech"
+	depends on HSI && SSI_PROTOCOL
+	help
+	If you say Y here, you will enable the CMT speech protocol used
+	by Nokia modems. If you say M the protocol will be available as
+	module named cmt_speech.
+
+	If unsure, say N.
+
 config SSI_PROTOCOL
 	tristate "SSI protocol"
 	depends on HSI && PHONET && OMAP_SSI

drivers/hsi/clients/Makefile

@@ -4,4 +4,5 @@
 
 obj-$(CONFIG_NOKIA_MODEM)	+= nokia-modem.o
 obj-$(CONFIG_SSI_PROTOCOL)	+= ssi_protocol.o
+obj-$(CONFIG_CMT_SPEECH)	+= cmt_speech.o
 obj-$(CONFIG_HSI_CHAR)		+= hsi_char.o

include/uapi/linux/hsi/Kbuild

 # UAPI Header export list
-header-y += hsi_char.h
+header-y += hsi_char.h cs-protocol.h

include/uapi/linux/hsi/cs-protocol.h

+/*
+ * cmt-speech interface definitions
+ *
+ * Copyright (C) 2008,2009,2010 Nokia Corporation. All rights reserved.
+ *
+ * Contact: Kai Vehmanen <kai.vehmanen@nokia.com>
+ * Original author: Peter Ujfalusi <peter.ujfalusi@nokia.com>
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA
+ */
+
+#ifndef _CS_PROTOCOL_H
+#define _CS_PROTOCOL_H
+
+#include <linux/types.h>
+#include <linux/ioctl.h>
+
+/* chardev parameters */
+#define CS_DEV_FILE_NAME		"/dev/cmt_speech"
+
+/* user-space API versioning */
+#define CS_IF_VERSION			2
+
+/* APE kernel <-> user space messages */
+#define CS_CMD_SHIFT			28
+#define CS_DOMAIN_SHIFT			24
+
+#define CS_CMD_MASK			0xff000000
+#define CS_PARAM_MASK			0xffffff
+
+#define CS_CMD(id, dom) \
+	(((id) << CS_CMD_SHIFT) | ((dom) << CS_DOMAIN_SHIFT))
+
+#define CS_ERROR			CS_CMD(1, 0)
+#define CS_RX_DATA_RECEIVED		CS_CMD(2, 0)
+#define CS_TX_DATA_READY		CS_CMD(3, 0)
+#define CS_TX_DATA_SENT			CS_CMD(4, 0)
+
+/* params to CS_ERROR indication */
+#define CS_ERR_PEER_RESET		0
+
+/* ioctl interface */
+
+/* parameters to CS_CONFIG_BUFS ioctl */
+#define CS_FEAT_TSTAMP_RX_CTRL		(1 << 0)
+#define CS_FEAT_ROLLING_RX_COUNTER	(2 << 0)
+
+/* parameters to CS_GET_STATE ioctl */
+#define CS_STATE_CLOSED			0
+#define CS_STATE_OPENED			1 /* resource allocated */
+#define CS_STATE_CONFIGURED		2 /* data path active */
+
+/* maximum number of TX/RX buffers */
+#define CS_MAX_BUFFERS_SHIFT		4
+#define CS_MAX_BUFFERS			(1 << CS_MAX_BUFFERS_SHIFT)
+
+/* Parameters for setting up the data buffers */
+struct cs_buffer_config {
+	__u32 rx_bufs;	/* number of RX buffer slots */
+	__u32 tx_bufs;	/* number of TX buffer slots */
+	__u32 buf_size;	/* bytes */
+	__u32 flags;	/* see CS_FEAT_* */
+	__u32 reserved[4];
+};
+
+/*
+ * Struct describing the layout and contents of the driver mmap area.
+ * This information is meant as read-only information for the application.
+ */
+struct cs_mmap_config_block {
+	__u32 reserved1;
+	__u32 buf_size;		/* 0=disabled, otherwise the transfer size */
+	__u32 rx_bufs;		/* # of RX buffers */
+	__u32 tx_bufs;		/* # of TX buffers */
+	__u32 reserved2;
+	/* array of offsets within the mmap area for each RX and TX buffer */
+	__u32 rx_offsets[CS_MAX_BUFFERS];
+	__u32 tx_offsets[CS_MAX_BUFFERS];
+	__u32 rx_ptr;
+	__u32 rx_ptr_boundary;
+	__u32 reserved3[2];
+	/*
+	 * if enabled with CS_FEAT_TSTAMP_RX_CTRL, monotonic
+	 * timestamp taken when the last control command was received
+	 */
+	struct timespec tstamp_rx_ctrl;
+};
+
+#define CS_IO_MAGIC		'C'
+
+#define CS_IOW(num, dtype)	_IOW(CS_IO_MAGIC, num, dtype)
+#define CS_IOR(num, dtype)	_IOR(CS_IO_MAGIC, num, dtype)
+#define CS_IOWR(num, dtype)	_IOWR(CS_IO_MAGIC, num, dtype)
+#define CS_IO(num)		_IO(CS_IO_MAGIC, num)
+
+#define CS_GET_STATE		CS_IOR(21, unsigned int)
+#define CS_SET_WAKELINE		CS_IOW(23, unsigned int)
+#define CS_GET_IF_VERSION	CS_IOR(30, unsigned int)
+#define CS_CONFIG_BUFS		CS_IOW(31, struct cs_buffer_config)
+
+#endif /* _CS_PROTOCOL_H */