new file mode 100644
@@ -0,0 +1,129 @@
+/*
+ * Copyright (C) ST-Ericsson AB 2010
+ * Contact: Sjur Brendeland / sjur.brandeland@stericsson.com
+ * Author: Amarnath Revanna / amarnath.bangalore.revanna@stericsson.com
+ * License terms: GNU General Public License (GPL) version 2
+ */
+
+#define pr_fmt(fmt) KBUILD_MODNAME ":" __func__ "():" fmt
+
+#include <linux/version.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/netdevice.h>
+#include <mach/mbox.h>
+#include <net/caif/caif_shm.h>
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("CAIF Shared Memory protocol driver");
+
+#define MAX_SHM_INSTANCES 1
+
+enum {
+ MBX_ACC0,
+ MBX_ACC1,
+ MBX_DSP
+};
+
+static struct shmdev_layer shmdev_lyr[MAX_SHM_INSTANCES];
+
+static unsigned int shm_start;
+static unsigned int shm_size;
+
+module_param(shm_size, uint , 0440);
+MODULE_PARM_DESC(shm_total_size, "Start of SHM shared memory");
+
+module_param(shm_start, uint , 0440);
+MODULE_PARM_DESC(shm_total_start, "Total Size of SHM shared memory");
+
+static int shmdev_send_msg(u32 dev_id, u32 mbx_msg)
+{
+ /* Always block until msg is written successfully */
+ mbox_send(shmdev_lyr[dev_id].hmbx, mbx_msg, true);
+ return 0;
+}
+
+static int shmdev_mbx_setup(void *pshmdrv_cb, struct shmdev_layer *pshm_dev,
+ void *pshm_drv)
+{
+ /*
+ * For UX5500, we have only 1 SHM instance which uses MBX0
+ * for communication with the peer modem
+ */
+ pshm_dev->hmbx = mbox_setup(MBX_ACC0, pshmdrv_cb, pshm_drv);
+
+ if (!pshm_dev->hmbx)
+ return -ENODEV;
+ else
+ return 0;
+}
+
+static int __init caif_shmdev_init(void)
+{
+ int i, result;
+
+ /* Loop is currently overkill, there is only one instance */
+ for (i = 0; i < MAX_SHM_INSTANCES; i++) {
+
+ shmdev_lyr[i].shm_base_addr = shm_start;
+ shmdev_lyr[i].shm_total_sz = shm_size;
+
+ if (((char *)shmdev_lyr[i].shm_base_addr == NULL)
+ || (shmdev_lyr[i].shm_total_sz <= 0)) {
+ pr_warn("ERROR,"
+ "Shared memory Address and/or Size incorrect"
+ ", Bailing out ...\n");
+ result = -EINVAL;
+ goto clean;
+ }
+
+ pr_info("SHM AREA (instance %d) STARTS"
+ " AT %p\n", i, (char *)shmdev_lyr[i].shm_base_addr);
+
+ shmdev_lyr[i].shm_id = i;
+ shmdev_lyr[i].pshmdev_mbxsend = shmdev_send_msg;
+ shmdev_lyr[i].pshmdev_mbxsetup = shmdev_mbx_setup;
+
+ /*
+ * Finally, CAIF core module is called with details in place:
+ * 1. SHM base address
+ * 2. SHM size
+ * 3. MBX handle
+ */
+ result = caif_shmcore_probe(&shmdev_lyr[i]);
+ if (result) {
+ pr_warn("ERROR[%d],"
+ "Could not probe SHM core (instance %d)"
+ " Bailing out ...\n", result, i);
+ goto clean;
+ }
+ }
+
+ return 0;
+
+clean:
+ /*
+ * For now, we assume that even if one instance of SHM fails, we bail
+ * out of the driver support completely. For this, we need to release
+ * any memory allocated and unregister any instance of SHM net device.
+ */
+ for (i = 0; i < MAX_SHM_INSTANCES; i++) {
+ if (shmdev_lyr[i].pshm_netdev)
+ unregister_netdev(shmdev_lyr[i].pshm_netdev);
+ }
+ return result;
+}
+
+static void __exit caif_shmdev_exit(void)
+{
+ int i;
+
+ for (i = 0; i < MAX_SHM_INSTANCES; i++) {
+ caif_shmcore_remove(shmdev_lyr[i].pshm_netdev);
+ kfree((void *)shmdev_lyr[i].shm_base_addr);
+ }
+
+}
+
+module_init(caif_shmdev_init);
+module_exit(caif_shmdev_exit);