drivers/usb/gadget/function/u_qdss.c

/* Copyright (c) 2012-2016, The Linux Foundation. All rights reserved.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 and
 * only 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
 */

#include <linux/kernel.h>
#include <linux/device.h>
#include <linux/usb/msm_hsusb.h>
#include <linux/usb_bam.h>

#include "gadget_chips.h"

struct  usb_qdss_bam_connect_info {
	u32 usb_bam_pipe_idx;
	u32 peer_pipe_idx;
	unsigned long usb_bam_handle;
	struct sps_mem_buffer *data_fifo;
};

static struct usb_qdss_bam_connect_info bam_info;

int alloc_sps_req(struct usb_ep *data_ep)
{
	struct usb_request *req = NULL;
	struct f_qdss *qdss = data_ep->driver_data;
	struct usb_gadget *gadget = qdss->cdev->gadget;
	u32 sps_params = 0;

	pr_debug("send_sps_req\n");

	req = usb_ep_alloc_request(data_ep, GFP_ATOMIC);
	if (!req) {
		pr_err("usb_ep_alloc_request failed\n");
		return -ENOMEM;
	}

	if (gadget_is_dwc3(gadget)) {
		req->length = 32*1024;
		sps_params = MSM_SPS_MODE | MSM_DISABLE_WB |
			bam_info.usb_bam_pipe_idx;
	} else {
		/* non DWC3 BAM requires req->length to be 0 */
		req->length = 0;
		sps_params = (MSM_SPS_MODE | bam_info.usb_bam_pipe_idx |
				MSM_VENDOR_ID) & ~MSM_IS_FINITE_TRANSFER;
	}
	req->udc_priv = sps_params;
	qdss->endless_req = req;

	return 0;
}

static int init_data(struct usb_ep *ep);
static int set_qdss_data_connection(struct usb_gadget *gadget,
	struct usb_ep *data_ep, u8 data_addr, int enable)
{
	enum usb_ctrl		usb_bam_type;
	int			res = 0;
	int			idx;
	struct f_qdss *qdss = data_ep->driver_data;

	pr_debug("set_qdss_data_connection\n");

	usb_bam_type = usb_bam_get_bam_type(gadget->name);

	/* There is only one qdss pipe, so the pipe number can be set to 0 */
	idx = usb_bam_get_connection_idx(usb_bam_type, QDSS_P_BAM,
		PEER_PERIPHERAL_TO_USB, USB_BAM_DEVICE, 0);
	if (idx < 0) {
		pr_err("%s: usb_bam_get_connection_idx failed\n", __func__);
		return idx;
	}

	if (enable) {
		usb_bam_alloc_fifos(usb_bam_type, idx);
		bam_info.data_fifo =
			kzalloc(sizeof(struct sps_mem_buffer), GFP_KERNEL);
		if (!bam_info.data_fifo) {
			pr_err("qdss_data_connection: memory alloc failed\n");
			return -ENOMEM;
		}
		get_bam2bam_connection_info(usb_bam_type, idx,
				&bam_info.usb_bam_pipe_idx,
				NULL, bam_info.data_fifo, NULL);

		alloc_sps_req(data_ep);
		if (gadget_is_dwc3(gadget))
			msm_data_fifo_config(data_ep,
					     bam_info.data_fifo->phys_base,
					     bam_info.data_fifo->size,
					     bam_info.usb_bam_pipe_idx);
		init_data(qdss->port.data);

		res = usb_bam_connect(usb_bam_type, idx,
					&(bam_info.usb_bam_pipe_idx));
		gadget->bam2bam_func_enabled = true;
	} else {
		kfree(bam_info.data_fifo);
		res = usb_bam_disconnect_pipe(usb_bam_type, idx);
		if (res)
			pr_err("usb_bam_disconnection error\n");
		usb_bam_free_fifos(usb_bam_type, idx);
	}

	return res;
}

static int init_data(struct usb_ep *ep)
{
	struct f_qdss *qdss = ep->driver_data;
	struct usb_gadget *gadget = qdss->cdev->gadget;
	int res = 0;

	pr_debug("init_data\n");

	if (gadget_is_dwc3(gadget)) {
		res = msm_ep_config(ep, qdss->endless_req);
		if (res)
			pr_err("msm_ep_config failed\n");
	} else {
		pr_debug("QDSS is used with non DWC3 core\n");
	}

	return res;
}

int uninit_data(struct usb_ep *ep)
{
	struct f_qdss *qdss = ep->driver_data;
	struct usb_gadget *gadget = qdss->cdev->gadget;
	int res = 0;

	pr_err("uninit_data\n");

	if (gadget_is_dwc3(gadget)) {
		res = msm_ep_unconfig(ep);
		if (res)
			pr_err("msm_ep_unconfig failed\n");
	}

	return res;
}