xshm: Config data use for platform devices.

This patch defines the configuration data needed to operate
on a channel. Each channel is represented as a platform device
containing the necessary configuration data to operate on the channel.

Signed-off-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/include/linux/xshm/xshm_pdev.h b/include/linux/xshm/xshm_pdev.h
new file mode 100644 (file)
index 0000000..0c223fb
--- /dev/null
+++ b/include/linux/xshm/xshm_pdev.h
@@ -0,0 +1,188 @@
+/*
+ * Copyright (C) ST-Ericsson AB 2010
+ * Author: Sjur Brendeland / sjur.brandeland@stericsson.com
+ * License terms: GNU General Public License (GPL) version 2
+ */
+
+#ifndef XSHM_PDEV_H_
+#define XSHM_PDEV_H_
+#include <linux/platform_device.h>
+
+#define XSHM_NAMESZ 16
+
+/**
+ * struct xshm_udchannel - Unidirectional channel for xshm driver.
+ *
+ * @addr: Base address of the channel, address must be
+ *               a kernel logical address.
+ * @buffers: The number of buffers in the channel.
+ * @ch_size: The size of data area for the channel in one direction.
+ * @xfer_bit: GENI/O bit used when sending data (write pointer move)
+ * @xfer_done_bit: GENI/O bit used to indicate avilable buffers
+ *     (read pointer move).
+ * @alignment: Alignment used in payload protocol.
+ * @mtu: Maxium Transfer Unit used for packet in a buffer (Packet mode).
+ * @packets: Maxium number of packets in a buffer (Packet mode).
+ * @state: State of the device 0 - Closed, 1 - Open
+ * @read: Specify the read index for a channel. In packed mode
+ *     this index will at any time refer to the next buffer available for read.
+ *     In stream mode, this will be the read index in the ring-buffer.
+ * @write: Specify the write index for a channel. In packed mode
+ *     this index will at any time refer to the next buffer available for
+ *     write. In stream mode, this will be the write index in the ring-buffer.
+ * @buf_size: In packet mode, this array contains the size of each buffer.
+ *     In stream mode this is unused.
+ *
+ * This external shared memory channel configuration is exported from the
+ * platform device. It gives the platform driver the
+ * necessary information for running the shared memory protocol
+ * between modem and host.
+ *
+ * Note that two instances of this configuration is needed in order to run a
+ * bi-directional channel.
+ */
+struct xshm_udchannel {
+       void *addr;
+       u32 buffers;
+       u32 ch_size;
+       u8 xfer_done_bit;
+       u8 xfer_bit;
+       u32 mtu;
+       u32 alignment;
+       u32 packets;
+       __le32 *state;
+       __le32 *read;
+       __le32 *write;
+       __le32 *buf_size;
+/* private: */
+       struct kobject kobj; /* kobj must be located at the end */
+};
+
+/**
+ * struct xshm_channel - Channel definition for xshm driver.
+ * @rx: Configuration for RX channel
+ * @tx: Configuration for TX channel
+ * @excl_group: Only channels with the same group ID can be open simultaneously.
+ * @mode: Configuring type of channel PACKET(1), STREAM(2)
+ * @name: Name of interface.
+ * @priority: Priority of the channel.
+ * @latency: Latency of the channel.
+ */
+struct xshm_channel {
+       struct xshm_udchannel rx, tx;
+       u32 excl_group;
+       u32 mode;
+       char name[XSHM_NAMESZ];
+       u32 priority;
+       u32 latency;
+};
+
+#define XSHM_OPEN   1
+#define XSHM_CLOSED 0
+
+enum xshm_dev_state {
+       XSHM_DEV_CLOSED = 0,
+       XSHM_DEV_OPENING,
+       XSHM_DEV_OPEN,
+       XSHM_DEV_ACTIVE,
+};
+
+/**
+ * struct xshm_dev - Device definition for xshm platform device.
+ *
+ * @pdev: Platform device
+ * @cfg: Configuration for the Channel
+ * @state: State of the device: Closed - No user space client is using it,
+ *     Open - Open but no payload queued, Active - Payload queued on device.
+ *
+ * @open: The driver calls open() when channel is taken into use.
+ *     This function will fail if channel configuration is inconsistent,
+ *     or upon resource conflicts with other channels.
+ *
+ * @open_cb: The device calls open_cb() when is ready for use.
+ *
+ * @close: Called by the driver when a channel is no longer in use.
+ *
+ * @close_cb: The device calls close_cb() to notify about remote side closure.
+ *
+ * @ipc_tx_release_cb: This callback is triggered by the modem when a
+ *     transmit operation has completed and the buffer can be reused.
+ *     This function must be set by the driver upon device registration.
+ *     The "more" flag is set if ipc_rx_cb() call is coming immediately
+ *     after this call to ipc_tx_release_cb().
+ *
+ * @ipc_rx_cb: The driver gets this callback when the modem sends a buffer
+ *     from the modem. The driver must call ipc_rx_release()
+ *     to make the buffer available again when the received buffer has been
+ *     processed.
+ *     This function pointer must be set by the driver upon device
+ *     registration.
+ *
+ * @ipc_rx_release: Called by the driver when a RX operation has completed
+ *     and that the rx-buffer is released.
+ *
+ * @ipc_tx: Called by the driver when a TX buffer shall be sent to the modem.
+ *
+ * @driver_data: pointer to driver specific data.
+ *
+ * When communicating between two systems (e.g. modem and host),
+ * external shared memory can bused (e.g. C2C or DPRAM).
+ *
+ * This structure is used by the platform device representing the
+ * External Shared Memory.
+ *
+ * The this structure contains configuration data for the platform device and
+ * functions pointers for IPC communication between Linux host and modem.
+ * The external shared memory protocol memory e.g. C2C or DPRAM
+ * together is a IPC mechanism for transporting small commands such as
+ * Mailbox or GENI/O.
+ *
+ * This data structure is initiated by the xshm platform device, except
+ * for the functions ipc_rx_cb() and ipc_tx_release_cb(). They must be set by
+ * the platform driver when device is registering.
+ */
+
+struct xshm_dev {
+       struct platform_device pdev;
+       struct xshm_channel cfg;
+       enum xshm_dev_state state;
+       int (*open)(struct xshm_dev *dev);
+       void (*close)(struct xshm_dev *dev);
+       int (*ipc_rx_release)(struct xshm_dev *dev, bool more);
+       int (*ipc_tx)(struct xshm_dev *dev);
+       int (*open_cb)(void *drv);
+       void (*close_cb)(void *drv);
+       int (*ipc_rx_cb)(void *drv);
+       int (*ipc_tx_release_cb)(void *drv);
+       void *driver_data;
+       /* private: */
+       struct list_head node;
+       void *priv;
+};
+
+/**
+ * xshm_create_dev() - Create an instance of the xshm platform device.
+ * @shmdev: Device configuration data.
+ */
+int xshm_register_dev(struct xshm_dev *shmdev);
+
+/** xshm_ipc_ready() - Notify that GENO bit READY_FOR_IPC is set
+*/
+void xshm_ipc_ready(void);
+
+/** xshm_caif_ready() - Notify that GENO bit READY_FOR_CAIF is set
+*/
+void xshm_caif_ready(void);
+
+extern bool ready_for_ipc;
+extern bool ready_for_caif;
+void xshm_put(struct xshm_dev *shmdev);
+struct xshm_dev *xshmdev_alloc(void);
+void xshmdev_free(struct xshm_dev *dev);
+void remove_devices(void);
+void close_devices(void);
+void xshm_boot_exit(void);
+int xshm_boot_init(void);
+void xshm_reset(void);
+void genio_ipc_ready_cb(void);
+#endif