/*
 *
 *  Bluetooth support for Intel devices
 *
 *  Copyright (C) 2015  Intel Corporation
 *
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  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.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#include <linux/module.h>
#include <linux/firmware.h>
#include <linux/regmap.h>

#include <net/bluetooth/bluetooth.h>
#include <net/bluetooth/hci_core.h>

#include "btintel.h"

#define VERSION "0.1"

#define BDADDR_INTEL (&(bdaddr_t) {{0x00, 0x8b, 0x9e, 0x19, 0x03, 0x00}})

int btintel_check_bdaddr(struct hci_dev *hdev)
{
	struct hci_rp_read_bd_addr *bda;
	struct sk_buff *skb;

	skb = __hci_cmd_sync(hdev, HCI_OP_READ_BD_ADDR, 0, NULL,
			     HCI_INIT_TIMEOUT);
	if (IS_ERR(skb)) {
		int err = PTR_ERR(skb);
		bt_dev_err(hdev, "Reading Intel device address failed (%d)",
			   err);
		return err;
	}

	if (skb->len != sizeof(*bda)) {
		bt_dev_err(hdev, "Intel device address length mismatch");
		kfree_skb(skb);
		return -EIO;
	}

	bda = (struct hci_rp_read_bd_addr *)skb->data;

	/* For some Intel based controllers, the default Bluetooth device
	 * address 00:03:19:9E:8B:00 can be found. These controllers are
	 * fully operational, but have the danger of duplicate addresses
	 * and that in turn can cause problems with Bluetooth operation.
	 */
	if (!bacmp(&bda->bdaddr, BDADDR_INTEL)) {
		bt_dev_err(hdev, "Found Intel default device address (%pMR)",
			   &bda->bdaddr);
		set_bit(HCI_QUIRK_INVALID_BDADDR, &hdev->quirks);
	}

	kfree_skb(skb);

	return 0;
}
EXPORT_SYMBOL_GPL(btintel_check_bdaddr);

int btintel_enter_mfg(struct hci_dev *hdev)
{
	const u8 param[] = { 0x01, 0x00 };
	struct sk_buff *skb;

	skb = __hci_cmd_sync(hdev, 0xfc11, 2, param, HCI_CMD_TIMEOUT);
	if (IS_ERR(skb)) {
		bt_dev_err(hdev, "Entering manufacturer mode failed (%ld)",
			   PTR_ERR(skb));
		return PTR_ERR(skb);
	}
	kfree_skb(skb);

	return 0;
}
EXPORT_SYMBOL_GPL(btintel_enter_mfg);

int btintel_exit_mfg(struct hci_dev *hdev, bool reset, bool patched)
{
	u8 param[] = { 0x00, 0x00 };
	struct sk_buff *skb;

	/* The 2nd command parameter specifies the manufacturing exit method:
	 * 0x00: Just disable the manufacturing mode (0x00).
	 * 0x01: Disable manufacturing mode and reset with patches deactivated.
	 * 0x02: Disable manufacturing mode and reset with patches activated.
	 */
	if (reset)
		param[1] |= patched ? 0x02 : 0x01;

	skb = __hci_cmd_sync(hdev, 0xfc11, 2, param, HCI_CMD_TIMEOUT);
	if (IS_ERR(skb)) {
		bt_dev_err(hdev, "Exiting manufacturer mode failed (%ld)",
			   PTR_ERR(skb));
		return PTR_ERR(skb);
	}
	kfree_skb(skb);

	return 0;
}
EXPORT_SYMBOL_GPL(btintel_exit_mfg);

int btintel_set_bdaddr(struct hci_dev *hdev, const bdaddr_t *bdaddr)
{
	struct sk_buff *skb;
	int err;

	skb = __hci_cmd_sync(hdev, 0xfc31, 6, bdaddr, HCI_INIT_TIMEOUT);
	if (IS_ERR(skb)) {
		err = PTR_ERR(skb);
		bt_dev_err(hdev, "Changing Intel device address failed (%d)",
			   err);
		return err;
	}
	kfree_skb(skb);

	return 0;
}
EXPORT_SYMBOL_GPL(btintel_set_bdaddr);

int btintel_set_diag(struct hci_dev *hdev, bool enable)
{
	struct sk_buff *skb;
	u8 param[3];
	int err;

	if (enable) {
		param[0] = 0x03;
		param[1] = 0x03;
		param[2] = 0x03;
	} else {
		param[0] = 0x00;
		param[1] = 0x00;
		param[2] = 0x00;
	}

	skb = __hci_cmd_sync(hdev, 0xfc43, 3, param, HCI_INIT_TIMEOUT);
	if (IS_ERR(skb)) {
		err = PTR_ERR(skb);
		if (err == -ENODATA)
			goto done;
		bt_dev_err(hdev, "Changing Intel diagnostic mode failed (%d)",
			   err);
		return err;
	}
	kfree_skb(skb);

done:
	btintel_set_event_mask(hdev, enable);
	return 0;
}
EXPORT_SYMBOL_GPL(btintel_set_diag);

int btintel_set_diag_mfg(struct hci_dev *hdev, bool enable)
{
	int err, ret;

	err = btintel_enter_mfg(hdev);
	if (err)
		return err;

	ret = btintel_set_diag(hdev, enable);

	err = btintel_exit_mfg(hdev, false, false);
	if (err)
		return err;

	return ret;
}
EXPORT_SYMBOL_GPL(btintel_set_diag_mfg);

void btintel_hw_error(struct hci_dev *hdev, u8 code)
{
	struct sk_buff *skb;
	u8 type = 0x00;

	bt_dev_err(hdev, "Hardware error 0x%2.2x", code);

	skb = __hci_cmd_sync(hdev, HCI_OP_RESET, 0, NULL, HCI_INIT_TIMEOUT);
	if (IS_ERR(skb)) {
		bt_dev_err(hdev, "Reset after hardware error failed (%ld)",
			   PTR_ERR(skb));
		return;
	}
	kfree_skb(skb);

	skb = __hci_cmd_sync(hdev, 0xfc22, 1, &type, HCI_INIT_TIMEOUT);
	if (IS_ERR(skb)) {
		bt_dev_err(hdev, "Retrieving Intel exception info failed (%ld)",
			   PTR_ERR(skb));
		return;
	}

	if (skb->len != 13) {
		bt_dev_err(hdev, "Exception info size mismatch");
		kfree_skb(skb);
		return;
	}

	bt_dev_err(hdev, "Exception info %s", (char *)(skb->data + 1));

	kfree_skb(skb);
}
EXPORT_SYMBOL_GPL(btintel_hw_error);

void btintel_version_info(struct hci_dev *hdev, struct intel_version *ver)
{
	const char *variant;

	switch (ver->fw_variant) {
	case 0x06:
		variant = "Bootloader";
		break;
	case 0x23:
		variant = "Firmware";
		break;
	default:
		return;
	}

	bt_dev_info(hdev, "%s revision %u.%u build %u week %u %u",
		    variant, ver->fw_revision >> 4, ver->fw_revision & 0x0f,
		    ver->fw_build_num, ver->fw_build_ww,
		    2000 + ver->fw_build_yy);
}
EXPORT_SYMBOL_GPL(btintel_version_info);

int btintel_secure_send(struct hci_dev *hdev, u8 fragment_type, u32 plen,
			const void *param)
{
	while (plen > 0) {
		struct sk_buff *skb;
		u8 cmd_param[253], fragment_len = (plen > 252) ? 252 : plen;

		cmd_param[0] = fragment_type;
		memcpy(cmd_param + 1, param, fragment_len);

		skb = __hci_cmd_sync(hdev, 0xfc09, fragment_len + 1,
				     cmd_param, HCI_INIT_TIMEOUT);
		if (IS_ERR(skb))
			return PTR_ERR(skb);

		kfree_skb(skb);

		plen -= fragment_len;
		param += fragment_len;
	}

	return 0;
}
EXPORT_SYMBOL_GPL(btintel_secure_send);

int btintel_load_ddc_config(struct hci_dev *hdev, const char *ddc_name)
{
	const struct firmware *fw;
	struct sk_buff *skb;
	const u8 *fw_ptr;
	int err;

	err = request_firmware_direct(&fw, ddc_name, &hdev->dev);
	if (err < 0) {
		bt_dev_err(hdev, "Failed to load Intel DDC file %s (%d)",
			   ddc_name, err);
		return err;
	}

	bt_dev_info(hdev, "Found Intel DDC parameters: %s", ddc_name);

	fw_ptr = fw->data;

	/* DDC file contains one or more DDC structure which has
	 * Length (1 byte), DDC ID (2 bytes), and DDC value (Length - 2).
	 */
	while (fw->size > fw_ptr - fw->data) {
		u8 cmd_plen = fw_ptr[0] + sizeof(u8);

		skb = __hci_cmd_sync(hdev, 0xfc8b, cmd_plen, fw_ptr,
				     HCI_INIT_TIMEOUT);
		if (IS_ERR(skb)) {
			bt_dev_err(hdev, "Failed to send Intel_Write_DDC (%ld)",
				   PTR_ERR(skb));
			release_firmware(fw);
			return PTR_ERR(skb);
		}

		fw_ptr += cmd_plen;
		kfree_skb(skb);
	}

	release_firmware(fw);

	bt_dev_info(hdev, "Applying Intel DDC parameters completed");

	return 0;
}
EXPORT_SYMBOL_GPL(btintel_load_ddc_config);

int btintel_set_event_mask(struct hci_dev *hdev, bool debug)
{
	/* Three events are enabled by default in the event mask as they are
	 * used during the startup sequence of the device and debugging purpose.
	 * The remaining events are thereby disabled by default but can be
	 * enabled as desired. Enabled events are
	 * 0000000000000001H HCI_Intel_Bootup ,
	 * 0000000000000400H HCI_Intel_Fatal_Exception Event and
	 * 0000000000000800H HCI_Intel_System_Exception Event
	 */
	u8 mask[8] = { 0x01, 0x0c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
	struct sk_buff *skb;
	int err;

	if (debug)
		mask[1] |= 0x62;

	skb = __hci_cmd_sync(hdev, 0xfc52, 8, mask, HCI_INIT_TIMEOUT);
	if (IS_ERR(skb)) {
		err = PTR_ERR(skb);
		bt_dev_err(hdev, "Setting Intel event mask failed (%d)", err);
		return err;
	}
	kfree_skb(skb);

	return 0;
}
EXPORT_SYMBOL_GPL(btintel_set_event_mask);

int btintel_set_event_mask_mfg(struct hci_dev *hdev, bool debug)
{
	int err, ret;

	err = btintel_enter_mfg(hdev);
	if (err)
		return err;

	ret = btintel_set_event_mask(hdev, debug);

	err = btintel_exit_mfg(hdev, false, false);
	if (err)
		return err;

	return ret;
}
EXPORT_SYMBOL_GPL(btintel_set_event_mask_mfg);

int btintel_read_version(struct hci_dev *hdev, struct intel_version *ver)
{
	struct sk_buff *skb;

	skb = __hci_cmd_sync(hdev, 0xfc05, 0, NULL, HCI_CMD_TIMEOUT);
	if (IS_ERR(skb)) {
		bt_dev_err(hdev, "Reading Intel version information failed (%ld)",
			   PTR_ERR(skb));
		return PTR_ERR(skb);
	}

	if (skb->len != sizeof(*ver)) {
		bt_dev_err(hdev, "Intel version event size mismatch");
		kfree_skb(skb);
		return -EILSEQ;
	}

	memcpy(ver, skb->data, sizeof(*ver));

	kfree_skb(skb);

	return 0;
}
EXPORT_SYMBOL_GPL(btintel_read_version);

void btintel_retry_fw_download(struct hci_dev *hdev)
{
	/* Send Intel Reset command. This will result in
	 * re-enumeration of BT controller.
	 */
	static const u8 reset_param[] = { 0x00, 0x01, 0x00, 0x00,
					0x00, 0x00, 0x00, 0x00 };
	struct sk_buff *skb;

	skb = __hci_cmd_sync(hdev, 0xfc01, sizeof(reset_param),
				reset_param, HCI_INIT_TIMEOUT);
	if (IS_ERR(skb)) {
		bt_dev_err(hdev, "Sending Intel Reset failed (%ld)",
				PTR_ERR(skb));
		return;
	}
	bt_dev_info(hdev, "Intel reset sent to retry FW download");
	kfree_skb(skb);
	/* Current Intel BT controllers(ThP/JfP) hold the USB reset
	 * lines for 2ms when it receives Intel Reset in bootloader mode.
	 * Whereas, the upcoming Intel BT controllers will hold USB reset
	 * for 150ms. To keep the delay generic, 150ms is chosen here.
	 */
	msleep(150);
}
EXPORT_SYMBOL_GPL(btintel_retry_fw_download);

/* ------- REGMAP IBT SUPPORT ------- */

#define IBT_REG_MODE_8BIT  0x00
#define IBT_REG_MODE_16BIT 0x01
#define IBT_REG_MODE_32BIT 0x02

struct regmap_ibt_context {
	struct hci_dev *hdev;
	__u16 op_write;
	__u16 op_read;
};

struct ibt_cp_reg_access {
	__le32  addr;
	__u8    mode;
	__u8    len;
	__u8    data[0];
} __packed;

struct ibt_rp_reg_access {
	__u8    status;
	__le32  addr;
	__u8    data[0];
} __packed;

static int regmap_ibt_read(void *context, const void *addr, size_t reg_size,
			   void *val, size_t val_size)
{
	struct regmap_ibt_context *ctx = context;
	struct ibt_cp_reg_access cp;
	struct ibt_rp_reg_access *rp;
	struct sk_buff *skb;
	int err = 0;

	if (reg_size != sizeof(__le32))
		return -EINVAL;

	switch (val_size) {
	case 1:
		cp.mode = IBT_REG_MODE_8BIT;
		break;
	case 2:
		cp.mode = IBT_REG_MODE_16BIT;
		break;
	case 4:
		cp.mode = IBT_REG_MODE_32BIT;
		break;
	default:
		return -EINVAL;
	}

	/* regmap provides a little-endian formatted addr */
	cp.addr = *(__le32 *)addr;
	cp.len = val_size;

	bt_dev_dbg(ctx->hdev, "Register (0x%x) read", le32_to_cpu(cp.addr));

	skb = hci_cmd_sync(ctx->hdev, ctx->op_read, sizeof(cp), &cp,
			   HCI_CMD_TIMEOUT);
	if (IS_ERR(skb)) {
		err = PTR_ERR(skb);
		bt_dev_err(ctx->hdev, "regmap: Register (0x%x) read error (%d)",
			   le32_to_cpu(cp.addr), err);
		return err;
	}

	if (skb->len != sizeof(*rp) + val_size) {
		bt_dev_err(ctx->hdev, "regmap: Register (0x%x) read error, bad len",
			   le32_to_cpu(cp.addr));
		err = -EINVAL;
		goto done;
	}

	rp = (struct ibt_rp_reg_access *)skb->data;

	if (rp->addr != cp.addr) {
		bt_dev_err(ctx->hdev, "regmap: Register (0x%x) read error, bad addr",
			   le32_to_cpu(rp->addr));
		err = -EINVAL;
		goto done;
	}

	memcpy(val, rp->data, val_size);

done:
	kfree_skb(skb);
	return err;
}

static int regmap_ibt_gather_write(void *context,
				   const void *addr, size_t reg_size,
				   const void *val, size_t val_size)
{
	struct regmap_ibt_context *ctx = context;
	struct ibt_cp_reg_access *cp;
	struct sk_buff *skb;
	int plen = sizeof(*cp) + val_size;
	u8 mode;
	int err = 0;

	if (reg_size != sizeof(__le32))
		return -EINVAL;

	switch (val_size) {
	case 1:
		mode = IBT_REG_MODE_8BIT;
		break;
	case 2:
		mode = IBT_REG_MODE_16BIT;
		break;
	case 4:
		mode = IBT_REG_MODE_32BIT;
		break;
	default:
		return -EINVAL;
	}

	cp = kmalloc(plen, GFP_KERNEL);
	if (!cp)
		return -ENOMEM;

	/* regmap provides a little-endian formatted addr/value */
	cp->addr = *(__le32 *)addr;
	cp->mode = mode;
	cp->len = val_size;
	memcpy(&cp->data, val, val_size);

	bt_dev_dbg(ctx->hdev, "Register (0x%x) write", le32_to_cpu(cp->addr));

	skb = hci_cmd_sync(ctx->hdev, ctx->op_write, plen, cp, HCI_CMD_TIMEOUT);
	if (IS_ERR(skb)) {
		err = PTR_ERR(skb);
		bt_dev_err(ctx->hdev, "regmap: Register (0x%x) write error (%d)",
			   le32_to_cpu(cp->addr), err);
		goto done;
	}
	kfree_skb(skb);

done:
	kfree(cp);
	return err;
}

static int regmap_ibt_write(void *context, const void *data, size_t count)
{
	/* data contains register+value, since we only support 32bit addr,
	 * minimum data size is 4 bytes.
	 */
	if (WARN_ONCE(count < 4, "Invalid register access"))
		return -EINVAL;

	return regmap_ibt_gather_write(context, data, 4, data + 4, count - 4);
}

static void regmap_ibt_free_context(void *context)
{
	kfree(context);
}

static struct regmap_bus regmap_ibt = {
	.read = regmap_ibt_read,
	.write = regmap_ibt_write,
	.gather_write = regmap_ibt_gather_write,
	.free_context = regmap_ibt_free_context,
	.reg_format_endian_default = REGMAP_ENDIAN_LITTLE,
	.val_format_endian_default = REGMAP_ENDIAN_LITTLE,
};

/* Config is the same for all register regions */
static const struct regmap_config regmap_ibt_cfg = {
	.name      = "btintel_regmap",
	.reg_bits  = 32,
	.val_bits  = 32,
};

struct regmap *btintel_regmap_init(struct hci_dev *hdev, u16 opcode_read,
				   u16 opcode_write)
{
	struct regmap_ibt_context *ctx;

	bt_dev_info(hdev, "regmap: Init R%x-W%x region", opcode_read,
		    opcode_write);

	ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
	if (!ctx)
		return ERR_PTR(-ENOMEM);

	ctx->op_read = opcode_read;
	ctx->op_write = opcode_write;
	ctx->hdev = hdev;

	return regmap_init(&hdev->dev, &regmap_ibt, ctx, &regmap_ibt_cfg);
}
EXPORT_SYMBOL_GPL(btintel_regmap_init);

MODULE_AUTHOR("Marcel Holtmann <marcel@holtmann.org>");
MODULE_DESCRIPTION("Bluetooth support for Intel devices ver " VERSION);
MODULE_VERSION(VERSION);
MODULE_LICENSE("GPL");
MODULE_FIRMWARE("intel/ibt-11-5.sfi");
MODULE_FIRMWARE("intel/ibt-11-5.ddc");
MODULE_FIRMWARE("intel/ibt-12-16.sfi");
MODULE_FIRMWARE("intel/ibt-12-16.ddc");