/*
   * (C) Copyright 2008 - 2009
   * Windriver, <www.windriver.com>
   * Tom Rix <Tom.Rix@windriver.com>
   *
   * Copyright 2011 Sebastian Andrzej Siewior <bigeasy@linutronix.de>
   *
   * Copyright 2014 Linaro, Ltd.
   * Rob Herring <robh@kernel.org>
   *
   * SPDX-License-Identifier:	GPL-2.0+
   */

  #include <config.h>

  #include <common.h>
  #include <errno.h>
  #include <malloc.h>
  #include <linux/usb/ch9.h>
  #include <linux/usb/gadget.h>
  #include <linux/usb/composite.h>
  #include <linux/compiler.h>
  #include <version.h>
  #include <g_dnl.h>

  #ifdef CONFIG_FASTBOOT_FLASH_MMC_DEV
  #include <fb_mmc.h>
  #endif

  
  #define FASTBOOT_VERSION		"0.4"
  
  #define FASTBOOT_INTERFACE_CLASS	0xff
  #define FASTBOOT_INTERFACE_SUB_CLASS	0x42
  #define FASTBOOT_INTERFACE_PROTOCOL	0x03
  
  #define RX_ENDPOINT_MAXIMUM_PACKET_SIZE_2_0  (0x0200)
  #define RX_ENDPOINT_MAXIMUM_PACKET_SIZE_1_1  (0x0040)
  #define TX_ENDPOINT_MAXIMUM_PACKET_SIZE      (0x0040)
  
  /* The 64 defined bytes plus \0 */
  #define RESPONSE_LEN	(64 + 1)
  
  #define EP_BUFFER_SIZE			4096
  
  struct f_fastboot {
  	struct usb_function usb_function;

  	/* IN/OUT EP's and corresponding requests */

  	struct usb_ep *in_ep, *out_ep;
  	struct usb_request *in_req, *out_req;
  };
  
  static inline struct f_fastboot *func_to_fastboot(struct usb_function *f)
  {
  	return container_of(f, struct f_fastboot, usb_function);
  }
  
  static struct f_fastboot *fastboot_func;
  static unsigned int download_size;
  static unsigned int download_bytes;
  
  static struct usb_endpoint_descriptor fs_ep_in = {
  	.bLength            = USB_DT_ENDPOINT_SIZE,
  	.bDescriptorType    = USB_DT_ENDPOINT,
  	.bEndpointAddress   = USB_DIR_IN,
  	.bmAttributes       = USB_ENDPOINT_XFER_BULK,
  	.wMaxPacketSize     = TX_ENDPOINT_MAXIMUM_PACKET_SIZE,
  	.bInterval          = 0x00,
  };
  
  static struct usb_endpoint_descriptor fs_ep_out = {
  	.bLength		= USB_DT_ENDPOINT_SIZE,
  	.bDescriptorType	= USB_DT_ENDPOINT,
  	.bEndpointAddress	= USB_DIR_OUT,
  	.bmAttributes		= USB_ENDPOINT_XFER_BULK,
  	.wMaxPacketSize		= RX_ENDPOINT_MAXIMUM_PACKET_SIZE_1_1,
  	.bInterval		= 0x00,
  };
  
  static struct usb_endpoint_descriptor hs_ep_out = {
  	.bLength		= USB_DT_ENDPOINT_SIZE,
  	.bDescriptorType	= USB_DT_ENDPOINT,
  	.bEndpointAddress	= USB_DIR_OUT,
  	.bmAttributes		= USB_ENDPOINT_XFER_BULK,
  	.wMaxPacketSize		= RX_ENDPOINT_MAXIMUM_PACKET_SIZE_2_0,
  	.bInterval		= 0x00,
  };
  
  static struct usb_interface_descriptor interface_desc = {
  	.bLength		= USB_DT_INTERFACE_SIZE,
  	.bDescriptorType	= USB_DT_INTERFACE,
  	.bInterfaceNumber	= 0x00,
  	.bAlternateSetting	= 0x00,
  	.bNumEndpoints		= 0x02,
  	.bInterfaceClass	= FASTBOOT_INTERFACE_CLASS,
  	.bInterfaceSubClass	= FASTBOOT_INTERFACE_SUB_CLASS,
  	.bInterfaceProtocol	= FASTBOOT_INTERFACE_PROTOCOL,
  };
  
  static struct usb_descriptor_header *fb_runtime_descs[] = {
  	(struct usb_descriptor_header *)&interface_desc,
  	(struct usb_descriptor_header *)&fs_ep_in,
  	(struct usb_descriptor_header *)&hs_ep_out,
  	NULL,
  };
  
  /*
   * static strings, in UTF-8
   */
  static const char fastboot_name[] = "Android Fastboot";
  
  static struct usb_string fastboot_string_defs[] = {
  	[0].s = fastboot_name,
  	{  }			/* end of list */
  };
  
  static struct usb_gadget_strings stringtab_fastboot = {
  	.language	= 0x0409,	/* en-us */
  	.strings	= fastboot_string_defs,
  };
  
  static struct usb_gadget_strings *fastboot_strings[] = {
  	&stringtab_fastboot,
  	NULL,
  };
  
  static void rx_handler_command(struct usb_ep *ep, struct usb_request *req);
  
  static void fastboot_complete(struct usb_ep *ep, struct usb_request *req)
  {
  	int status = req->status;
  	if (!status)
  		return;
  	printf("status: %d ep '%s' trans: %d
  ", status, ep->name, req->actual);
  }
  
  static int fastboot_bind(struct usb_configuration *c, struct usb_function *f)
  {
  	int id;
  	struct usb_gadget *gadget = c->cdev->gadget;
  	struct f_fastboot *f_fb = func_to_fastboot(f);
  
  	/* DYNAMIC interface numbers assignments */
  	id = usb_interface_id(c, f);
  	if (id < 0)
  		return id;
  	interface_desc.bInterfaceNumber = id;
  
  	id = usb_string_id(c->cdev);
  	if (id < 0)
  		return id;
  	fastboot_string_defs[0].id = id;
  	interface_desc.iInterface = id;
  
  	f_fb->in_ep = usb_ep_autoconfig(gadget, &fs_ep_in);
  	if (!f_fb->in_ep)
  		return -ENODEV;
  	f_fb->in_ep->driver_data = c->cdev;
  
  	f_fb->out_ep = usb_ep_autoconfig(gadget, &fs_ep_out);
  	if (!f_fb->out_ep)
  		return -ENODEV;
  	f_fb->out_ep->driver_data = c->cdev;
  
  	hs_ep_out.bEndpointAddress = fs_ep_out.bEndpointAddress;
  
  	return 0;
  }
  
  static void fastboot_unbind(struct usb_configuration *c, struct usb_function *f)
  {
  	memset(fastboot_func, 0, sizeof(*fastboot_func));
  }
  
  static void fastboot_disable(struct usb_function *f)
  {
  	struct f_fastboot *f_fb = func_to_fastboot(f);
  
  	usb_ep_disable(f_fb->out_ep);
  	usb_ep_disable(f_fb->in_ep);
  
  	if (f_fb->out_req) {
  		free(f_fb->out_req->buf);
  		usb_ep_free_request(f_fb->out_ep, f_fb->out_req);
  		f_fb->out_req = NULL;
  	}
  	if (f_fb->in_req) {
  		free(f_fb->in_req->buf);
  		usb_ep_free_request(f_fb->in_ep, f_fb->in_req);
  		f_fb->in_req = NULL;
  	}
  }
  
  static struct usb_request *fastboot_start_ep(struct usb_ep *ep)
  {
  	struct usb_request *req;
  
  	req = usb_ep_alloc_request(ep, 0);
  	if (!req)
  		return NULL;
  
  	req->length = EP_BUFFER_SIZE;
  	req->buf = memalign(CONFIG_SYS_CACHELINE_SIZE, EP_BUFFER_SIZE);
  	if (!req->buf) {
  		usb_ep_free_request(ep, req);
  		return NULL;
  	}
  
  	memset(req->buf, 0, req->length);
  	return req;
  }
  
  static int fastboot_set_alt(struct usb_function *f,
  			    unsigned interface, unsigned alt)
  {
  	int ret;
  	struct usb_composite_dev *cdev = f->config->cdev;
  	struct usb_gadget *gadget = cdev->gadget;
  	struct f_fastboot *f_fb = func_to_fastboot(f);
  
  	debug("%s: func: %s intf: %d alt: %d
  ",
  	      __func__, f->name, interface, alt);
  
  	/* make sure we don't enable the ep twice */
  	if (gadget->speed == USB_SPEED_HIGH)
  		ret = usb_ep_enable(f_fb->out_ep, &hs_ep_out);
  	else
  		ret = usb_ep_enable(f_fb->out_ep, &fs_ep_out);
  	if (ret) {
  		puts("failed to enable out ep
  ");
  		return ret;
  	}
  
  	f_fb->out_req = fastboot_start_ep(f_fb->out_ep);
  	if (!f_fb->out_req) {
  		puts("failed to alloc out req
  ");
  		ret = -EINVAL;
  		goto err;
  	}
  	f_fb->out_req->complete = rx_handler_command;
  
  	ret = usb_ep_enable(f_fb->in_ep, &fs_ep_in);
  	if (ret) {
  		puts("failed to enable in ep
  ");
  		goto err;
  	}
  
  	f_fb->in_req = fastboot_start_ep(f_fb->in_ep);
  	if (!f_fb->in_req) {
  		puts("failed alloc req in
  ");
  		ret = -EINVAL;
  		goto err;
  	}
  	f_fb->in_req->complete = fastboot_complete;
  
  	ret = usb_ep_queue(f_fb->out_ep, f_fb->out_req, 0);
  	if (ret)
  		goto err;
  
  	return 0;
  err:
  	fastboot_disable(f);
  	return ret;
  }
  
  static int fastboot_add(struct usb_configuration *c)
  {
  	struct f_fastboot *f_fb = fastboot_func;
  	int status;
  
  	debug("%s: cdev: 0x%p
  ", __func__, c->cdev);
  
  	if (!f_fb) {
  		f_fb = memalign(CONFIG_SYS_CACHELINE_SIZE, sizeof(*f_fb));
  		if (!f_fb)
  			return -ENOMEM;
  
  		fastboot_func = f_fb;
  		memset(f_fb, 0, sizeof(*f_fb));
  	}
  
  	f_fb->usb_function.name = "f_fastboot";
  	f_fb->usb_function.hs_descriptors = fb_runtime_descs;
  	f_fb->usb_function.bind = fastboot_bind;
  	f_fb->usb_function.unbind = fastboot_unbind;
  	f_fb->usb_function.set_alt = fastboot_set_alt;
  	f_fb->usb_function.disable = fastboot_disable;
  	f_fb->usb_function.strings = fastboot_strings;
  
  	status = usb_add_function(c, &f_fb->usb_function);
  	if (status) {
  		free(f_fb);
  		fastboot_func = f_fb;
  	}
  
  	return status;
  }
  DECLARE_GADGET_BIND_CALLBACK(usb_dnl_fastboot, fastboot_add);

  static int fastboot_tx_write(const char *buffer, unsigned int buffer_size)

  {
  	struct usb_request *in_req = fastboot_func->in_req;
  	int ret;
  
  	memcpy(in_req->buf, buffer, buffer_size);
  	in_req->length = buffer_size;
  	ret = usb_ep_queue(fastboot_func->in_ep, in_req, 0);
  	if (ret)
  		printf("Error %d on queue
  ", ret);
  	return 0;
  }
  
  static int fastboot_tx_write_str(const char *buffer)
  {
  	return fastboot_tx_write(buffer, strlen(buffer));
  }
  
  static void compl_do_reset(struct usb_ep *ep, struct usb_request *req)
  {
  	do_reset(NULL, 0, 0, NULL);
  }
  
  static void cb_reboot(struct usb_ep *ep, struct usb_request *req)
  {
  	fastboot_func->in_req->complete = compl_do_reset;
  	fastboot_tx_write_str("OKAY");
  }
  
  static int strcmp_l1(const char *s1, const char *s2)
  {
  	if (!s1 || !s2)
  		return -1;
  	return strncmp(s1, s2, strlen(s1));
  }
  
  static void cb_getvar(struct usb_ep *ep, struct usb_request *req)
  {
  	char *cmd = req->buf;
  	char response[RESPONSE_LEN];
  	const char *s;

  	size_t chars_left;

  
  	strcpy(response, "OKAY");

  	chars_left = sizeof(response) - strlen(response) - 1;

  	strsep(&cmd, ":");
  	if (!cmd) {

  		error("missing variable
  ");

  		fastboot_tx_write_str("FAILmissing var");
  		return;
  	}
  
  	if (!strcmp_l1("version", cmd)) {

  		strncat(response, FASTBOOT_VERSION, chars_left);

  	} else if (!strcmp_l1("bootloader-version", cmd)) {

  		strncat(response, U_BOOT_VERSION, chars_left);

  	} else if (!strcmp_l1("downloadsize", cmd) ||
  		!strcmp_l1("max-download-size", cmd)) {

  		char str_num[12];

  		sprintf(str_num, "0x%08x", CONFIG_USB_FASTBOOT_BUF_SIZE);

  		strncat(response, str_num, chars_left);

  	} else if (!strcmp_l1("serialno", cmd)) {
  		s = getenv("serial#");
  		if (s)

  			strncat(response, s, chars_left);

  		else
  			strcpy(response, "FAILValue not set");
  	} else {

  		error("unknown variable: %s
  ", cmd);

  		strcpy(response, "FAILVariable not implemented");
  	}
  	fastboot_tx_write_str(response);
  }
  
  static unsigned int rx_bytes_expected(void)
  {
  	int rx_remain = download_size - download_bytes;
  	if (rx_remain < 0)
  		return 0;
  	if (rx_remain > EP_BUFFER_SIZE)
  		return EP_BUFFER_SIZE;
  	return rx_remain;
  }
  
  #define BYTES_PER_DOT	0x20000
  static void rx_handler_dl_image(struct usb_ep *ep, struct usb_request *req)
  {
  	char response[RESPONSE_LEN];
  	unsigned int transfer_size = download_size - download_bytes;
  	const unsigned char *buffer = req->buf;
  	unsigned int buffer_size = req->actual;

  	unsigned int pre_dot_num, now_dot_num;

  
  	if (req->status != 0) {
  		printf("Bad status: %d
  ", req->status);
  		return;
  	}
  
  	if (buffer_size < transfer_size)
  		transfer_size = buffer_size;
  
  	memcpy((void *)CONFIG_USB_FASTBOOT_BUF_ADDR + download_bytes,
  	       buffer, transfer_size);

  	pre_dot_num = download_bytes / BYTES_PER_DOT;

  	download_bytes += transfer_size;

  	now_dot_num = download_bytes / BYTES_PER_DOT;
  
  	if (pre_dot_num != now_dot_num) {
  		putc('.');
  		if (!(now_dot_num % 74))
  			putc('
  ');
  	}

  
  	/* Check if transfer is done */
  	if (download_bytes >= download_size) {
  		/*
  		 * Reset global transfer variable, keep download_bytes because
  		 * it will be used in the next possible flashing command
  		 */
  		download_size = 0;
  		req->complete = rx_handler_command;
  		req->length = EP_BUFFER_SIZE;
  
  		sprintf(response, "OKAY");
  		fastboot_tx_write_str(response);
  
  		printf("
  downloading of %d bytes finished
  ", download_bytes);
  	} else {
  		req->length = rx_bytes_expected();
  		if (req->length < ep->maxpacket)
  			req->length = ep->maxpacket;
  	}

  	req->actual = 0;
  	usb_ep_queue(ep, req, 0);
  }
  
  static void cb_download(struct usb_ep *ep, struct usb_request *req)
  {
  	char *cmd = req->buf;
  	char response[RESPONSE_LEN];
  
  	strsep(&cmd, ":");
  	download_size = simple_strtoul(cmd, NULL, 16);
  	download_bytes = 0;
  
  	printf("Starting download of %d bytes
  ", download_size);
  
  	if (0 == download_size) {
  		sprintf(response, "FAILdata invalid size");
  	} else if (download_size > CONFIG_USB_FASTBOOT_BUF_SIZE) {
  		download_size = 0;
  		sprintf(response, "FAILdata too large");
  	} else {
  		sprintf(response, "DATA%08x", download_size);
  		req->complete = rx_handler_dl_image;
  		req->length = rx_bytes_expected();
  		if (req->length < ep->maxpacket)
  			req->length = ep->maxpacket;
  	}
  	fastboot_tx_write_str(response);
  }
  
  static void do_bootm_on_complete(struct usb_ep *ep, struct usb_request *req)
  {
  	char boot_addr_start[12];
  	char *bootm_args[] = { "bootm", boot_addr_start, NULL };
  
  	puts("Booting kernel..
  ");
  
  	sprintf(boot_addr_start, "0x%lx", load_addr);
  	do_bootm(NULL, 0, 2, bootm_args);
  
  	/* This only happens if image is somehow faulty so we start over */
  	do_reset(NULL, 0, 0, NULL);
  }
  
  static void cb_boot(struct usb_ep *ep, struct usb_request *req)
  {
  	fastboot_func->in_req->complete = do_bootm_on_complete;
  	fastboot_tx_write_str("OKAY");
  }

  #ifdef CONFIG_FASTBOOT_FLASH
  static void cb_flash(struct usb_ep *ep, struct usb_request *req)
  {
  	char *cmd = req->buf;
  	char response[RESPONSE_LEN];
  
  	strsep(&cmd, ":");
  	if (!cmd) {

  		error("missing partition name
  ");

  		fastboot_tx_write_str("FAILmissing partition name");
  		return;
  	}
  
  	strcpy(response, "FAILno flash device defined");
  #ifdef CONFIG_FASTBOOT_FLASH_MMC_DEV
  	fb_mmc_flash_write(cmd, (void *)CONFIG_USB_FASTBOOT_BUF_ADDR,
  			   download_bytes, response);
  #endif
  	fastboot_tx_write_str(response);
  }
  #endif

  struct cmd_dispatch_info {
  	char *cmd;
  	void (*cb)(struct usb_ep *ep, struct usb_request *req);
  };
  
  static const struct cmd_dispatch_info cmd_dispatch_info[] = {
  	{
  		.cmd = "reboot",
  		.cb = cb_reboot,
  	}, {
  		.cmd = "getvar:",
  		.cb = cb_getvar,
  	}, {
  		.cmd = "download:",
  		.cb = cb_download,
  	}, {
  		.cmd = "boot",
  		.cb = cb_boot,
  	},

  #ifdef CONFIG_FASTBOOT_FLASH
  	{
  		.cmd = "flash",
  		.cb = cb_flash,
  	},
  #endif

  };
  
  static void rx_handler_command(struct usb_ep *ep, struct usb_request *req)
  {
  	char *cmdbuf = req->buf;
  	void (*func_cb)(struct usb_ep *ep, struct usb_request *req) = NULL;
  	int i;
  
  	for (i = 0; i < ARRAY_SIZE(cmd_dispatch_info); i++) {
  		if (!strcmp_l1(cmd_dispatch_info[i].cmd, cmdbuf)) {
  			func_cb = cmd_dispatch_info[i].cb;
  			break;
  		}
  	}

  	if (!func_cb) {
  		error("unknown command: %s
  ", cmdbuf);

  		fastboot_tx_write_str("FAILunknown command");

  	} else {

  		if (req->actual < req->length) {
  			u8 *buf = (u8 *)req->buf;
  			buf[req->actual] = 0;
  			func_cb(ep, req);
  		} else {
  			error("buffer overflow
  ");
  			fastboot_tx_write_str("FAILbuffer overflow");
  		}

  	}

  
  	if (req->status == 0) {
  		*cmdbuf = '\0';
  		req->actual = 0;
  		usb_ep_queue(ep, req, 0);
  	}
  }