/*
 *
 *  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 <asm/unaligned.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)
{
        static 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)
{
        u8 mask[8] = { 0x87, 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);

/* ------- 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);

int btintel_send_intel_reset(struct hci_dev *hdev, u32 boot_param)
{
        struct intel_reset params = { 0x00, 0x01, 0x00, 0x01, 0x00000000 };
        struct sk_buff *skb;

        params.boot_param = cpu_to_le32(boot_param);

        skb = __hci_cmd_sync(hdev, 0xfc01, sizeof(params), &params,
                             HCI_INIT_TIMEOUT);
        if (IS_ERR(skb)) {
                bt_dev_err(hdev, "Failed to send Intel Reset command");
                return PTR_ERR(skb);
        }

        kfree_skb(skb);

        return 0;
}
EXPORT_SYMBOL_GPL(btintel_send_intel_reset);

int btintel_read_boot_params(struct hci_dev *hdev,
                             struct intel_boot_params *params)
{
        struct sk_buff *skb;

        skb = __hci_cmd_sync(hdev, 0xfc0d, 0, NULL, HCI_INIT_TIMEOUT);
        if (IS_ERR(skb)) {
                bt_dev_err(hdev, "Reading Intel boot parameters failed (%ld)",
                           PTR_ERR(skb));
                return PTR_ERR(skb);
        }

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

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

        kfree_skb(skb);

        if (params->status) {
                bt_dev_err(hdev, "Intel boot parameters command failed (%02x)",
                           params->status);
                return -bt_to_errno(params->status);
        }

        bt_dev_info(hdev, "Device revision is %u",
                    le16_to_cpu(params->dev_revid));

        bt_dev_info(hdev, "Secure boot is %s",
                    params->secure_boot ? "enabled" : "disabled");

        bt_dev_info(hdev, "OTP lock is %s",
                    params->otp_lock ? "enabled" : "disabled");

        bt_dev_info(hdev, "API lock is %s",
                    params->api_lock ? "enabled" : "disabled");

        bt_dev_info(hdev, "Debug lock is %s",
                    params->debug_lock ? "enabled" : "disabled");

        bt_dev_info(hdev, "Minimum firmware build %u week %u %u",
                    params->min_fw_build_nn, params->min_fw_build_cw,
                    2000 + params->min_fw_build_yy);

        return 0;
}
EXPORT_SYMBOL_GPL(btintel_read_boot_params);

int btintel_download_firmware(struct hci_dev *hdev, const struct firmware *fw,
                              u32 *boot_param)
{
        int err;
        const u8 *fw_ptr;
        u32 frag_len;

        /* Start the firmware download transaction with the Init fragment
         * represented by the 128 bytes of CSS header.
         */
        err = btintel_secure_send(hdev, 0x00, 128, fw->data);
        if (err < 0) {
                bt_dev_err(hdev, "Failed to send firmware header (%d)", err);
                goto done;
        }

        /* Send the 256 bytes of public key information from the firmware
         * as the PKey fragment.
         */
        err = btintel_secure_send(hdev, 0x03, 256, fw->data + 128);
        if (err < 0) {
                bt_dev_err(hdev, "Failed to send firmware pkey (%d)", err);
                goto done;
        }

        /* Send the 256 bytes of signature information from the firmware
         * as the Sign fragment.
         */
        err = btintel_secure_send(hdev, 0x02, 256, fw->data + 388);
        if (err < 0) {
                bt_dev_err(hdev, "Failed to send firmware signature (%d)", err);
                goto done;
        }

        fw_ptr = fw->data + 644;
        frag_len = 0;

        while (fw_ptr - fw->data < fw->size) {
                struct hci_command_hdr *cmd = (void *)(fw_ptr + frag_len);

                /* Each SKU has a different reset parameter to use in the
                 * HCI_Intel_Reset command and it is embedded in the firmware
                 * data. So, instead of using static value per SKU, check
                 * the firmware data and save it for later use.
                 */
                if (le16_to_cpu(cmd->opcode) == 0xfc0e) {
                        /* The boot parameter is the first 32-bit value
                         * and rest of 3 octets are reserved.
                         */
                        *boot_param = get_unaligned_le32(fw_ptr + sizeof(*cmd));

                        bt_dev_dbg(hdev, "boot_param=0x%x", *boot_param);
                }

                frag_len += sizeof(*cmd) + cmd->plen;

                /* The parameter length of the secure send command requires
                 * a 4 byte alignment. It happens so that the firmware file
                 * contains proper Intel_NOP commands to align the fragments
                 * as needed.
                 *
                 * Send set of commands with 4 byte alignment from the
                 * firmware data buffer as a single Data fragement.
                 */
                if (!(frag_len % 4)) {
                        err = btintel_secure_send(hdev, 0x01, frag_len, fw_ptr);
                        if (err < 0) {
                                bt_dev_err(hdev,
                                           "Failed to send firmware data (%d)",
                                           err);
                                goto done;
                        }

                        fw_ptr += frag_len;
                        frag_len = 0;
                }
        }

done:
        return err;
}
EXPORT_SYMBOL_GPL(btintel_download_firmware);

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");