modem: Add M6718 modem SPI IPC driver framework

Adds support for the M6718 modem IPC SPI driver. This patch adds the
spi driver under which the protocol will be added.

ST-Ericsson ID: 369397
ST-Ericsson FOSS-OUT ID: STETL-FOSS-OUT-12224
ST-Ericsson Linux next: NA

Change-Id: Ifa60efa9cb6a9d30b02b88b563624a293bc0930c
Signed-off-by: Chris Blair <chris.blair@stericsson.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/36433
Reviewed-by: Jonas ABERG <jonas.aberg@stericsson.com>

1 files changed, 135 insertions, 0 deletions

diff --git a/include/linux/modem/m6718_spi/modem_driver.h b/include/linux/modem/m6718_spi/modem_driver.h
new file mode 100644
index 00000000000..8c5209c228c
--- /dev/null
+++ b/include/linux/modem/m6718_spi/modem_driver.h
@@ -0,0 +1,135 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2011
+ *
+ * Author: Chris Blair <chris.blair@stericsson.com> for ST-Ericsson
+ *   based on shrm_driver.h
+ *
+ * License terms: GNU General Public License (GPL) version 2
+ *
+ * Modem IPC driver interface header.
+ */
+#ifndef _MODEM_DRIVER_H_
+#define _MODEM_DRIVER_H_
+
+#include <linux/device.h>
+#include <linux/modem/modem.h>
+#include <linux/cdev.h>
+#include <linux/spi/spi.h>
+
+
+/* driver L2 mux channels */
+#ifdef CONFIG_MODEM_M6718_SPI_ENABLE_FEATURE_LOOPBACK
+#define MODEM_M6718_SPI_MAX_CHANNELS		(9)
+#else
+#define MODEM_M6718_SPI_MAX_CHANNELS		(3)
+#endif
+
+#define MODEM_M6718_SPI_CHN_ISI			(0)
+/*#define MODEM_M6718_SPI_CHN_RPC		(1) not supported */
+#define MODEM_M6718_SPI_CHN_AUDIO		(2)
+/*#define MODEM_M6718_SPI_CHN_SECURITY		(3) not supported */
+/*						(4) not supported */
+#ifdef CONFIG_MODEM_M6718_SPI_ENABLE_FEATURE_LOOPBACK
+#define MODEM_M6718_SPI_CHN_MASTER_LOOPBACK0	(5)
+#define MODEM_M6718_SPI_CHN_SLAVE_LOOPBACK0	(6)
+#define MODEM_M6718_SPI_CHN_MASTER_LOOPBACK1	(7)
+#define MODEM_M6718_SPI_CHN_SLAVE_LOOPBACK1	(8)
+#endif
+
+/**
+ * struct queue_element - information to add an element to queue
+ * @entry:	list entry
+ * @offset:	message offset
+ * @size:	message size
+ * @no:		total number of messages
+ */
+struct queue_element {
+	struct list_head entry;
+	u32 offset;
+	u32 size;
+	u32 no;
+};
+
+/**
+ * struct message_queue - ISI, RPC, AUDIO, SECURITY message queue information
+ * @channel:		L2 mux channel served by this queue
+ * @fifo_base:		pointer to the respective fifo base
+ * @size:		size of the data to be read
+ * @free:		free space in the queue
+ * @readptr:		fifo read pointer
+ * @writeptr:		fifo write pointer
+ * @no:			total number of messages
+ * @update_lock:	spinlock for protecting the queue read operation
+ * @q_rp:		queue read pointer is valid
+ * @wq_readable:	wait queue head
+ * @msg_list:		message list
+ * @modem_spi_dev:	pointer to modem device information structure
+ */
+struct message_queue {
+      u8 channel;
+      u8 *fifo_base;
+      u32 size;
+      u32 free;
+      u32 readptr;
+      u32 writeptr;
+      u32 no;
+      spinlock_t update_lock;
+      atomic_t q_rp;
+      wait_queue_head_t wq_readable;
+      struct list_head msg_list;
+      struct modem_spi_dev *modem_spi_dev;
+};
+
+/**
+ * struct isa_device_context - modem char interface device information
+ * @dl_queue:	structre to store the queue related info
+ * @device_id:	channel id (ISI, AUDIO, RPC, ...)
+ * @addr:	device address
+ */
+struct isa_device_context {
+	struct message_queue dl_queue;
+	u8 device_id;
+	void *addr;
+};
+
+/**
+ * struct isa_driver_context - modem char interface driver information
+ * @is_open:		flag to check the usage of queue
+ * @isadev:		pointer to struct t_isadev_context
+ * @common_tx_lock:	spinlock for protecting common channel
+ * @audio_tx_mutex:	mutex for protecting audio channel
+ * @cdev:		character device structre
+ * @modem_class:	pointer to the class structure
+ */
+struct isa_driver_context {
+	atomic_t is_open[MODEM_M6718_SPI_MAX_CHANNELS];
+	struct isa_device_context *isadev;
+	spinlock_t common_tx_lock;
+	struct mutex audio_tx_mutex;
+	struct cdev cdev;
+	struct class *modem_class;
+};
+
+/**
+ * struct modem_spi_dev - modem device information
+ * @dev			pointer to device
+ * @ndev		pointer to net_device interface
+ * @modem		pointer to registered modem structure
+ * @isa_context		pointer to char device interface
+ * @netdev_flag_up:	flag to indicate up/down of network device
+ * @msr_flag:		flag to indicate modem-silent-reset is in progress
+ */
+struct modem_spi_dev {
+	struct device *dev;
+	struct net_device *ndev;
+	struct modem *modem;
+	struct isa_driver_context *isa_context;
+	int netdev_flag_up;
+	bool msr_flag;
+};
+
+/* function exported for L1 to call with received frames */
+int modem_m6718_spi_receive(struct spi_device *sdev, u8 channel,
+	u32 len, void *data);
+
+#endif /* _MODEM_DRIVER_H_ */