559 lines
14 KiB
C
559 lines
14 KiB
C
/*
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* Marvell NFC driver: Firmware downloader
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*
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* Copyright (C) 2015, Marvell International Ltd.
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*
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* This software file (the "File") is distributed by Marvell International
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* Ltd. under the terms of the GNU General Public License Version 2, June 1991
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* (the "License"). You may use, redistribute and/or modify this File in
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* accordance with the terms and conditions of the License, a copy of which
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* is available on the worldwide web at
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* http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt.
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*
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* THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE
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* IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE
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* ARE EXPRESSLY DISCLAIMED. The License provides additional details about
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* this warranty disclaimer.
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*/
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#include <linux/module.h>
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#include <asm/unaligned.h>
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#include <linux/firmware.h>
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#include <linux/nfc.h>
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#include <net/nfc/nci.h>
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#include <net/nfc/nci_core.h>
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#include "nfcmrvl.h"
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#define FW_DNLD_TIMEOUT 15000
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#define NCI_OP_PROPRIETARY_BOOT_CMD nci_opcode_pack(NCI_GID_PROPRIETARY, \
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NCI_OP_PROP_BOOT_CMD)
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/* FW download states */
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enum {
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STATE_RESET = 0,
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STATE_INIT,
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STATE_SET_REF_CLOCK,
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STATE_SET_HI_CONFIG,
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STATE_OPEN_LC,
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STATE_FW_DNLD,
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STATE_CLOSE_LC,
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STATE_BOOT
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};
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enum {
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SUBSTATE_WAIT_COMMAND = 0,
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SUBSTATE_WAIT_ACK_CREDIT,
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SUBSTATE_WAIT_NACK_CREDIT,
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SUBSTATE_WAIT_DATA_CREDIT,
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};
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/*
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** Patterns for responses
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*/
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static const uint8_t nci_pattern_core_reset_ntf[] = {
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0x60, 0x00, 0x02, 0xA0, 0x01
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};
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static const uint8_t nci_pattern_core_init_rsp[] = {
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0x40, 0x01, 0x11
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};
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static const uint8_t nci_pattern_core_set_config_rsp[] = {
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0x40, 0x02, 0x02, 0x00, 0x00
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};
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static const uint8_t nci_pattern_core_conn_create_rsp[] = {
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0x40, 0x04, 0x04, 0x00
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};
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static const uint8_t nci_pattern_core_conn_close_rsp[] = {
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0x40, 0x05, 0x01, 0x00
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};
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static const uint8_t nci_pattern_core_conn_credits_ntf[] = {
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0x60, 0x06, 0x03, 0x01, NCI_CORE_LC_CONNID_PROP_FW_DL, 0x01
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};
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static const uint8_t nci_pattern_proprietary_boot_rsp[] = {
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0x4F, 0x3A, 0x01, 0x00
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};
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static struct sk_buff *alloc_lc_skb(struct nfcmrvl_private *priv, uint8_t plen)
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{
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struct sk_buff *skb;
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struct nci_data_hdr *hdr;
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skb = nci_skb_alloc(priv->ndev, (NCI_DATA_HDR_SIZE + plen), GFP_KERNEL);
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if (!skb) {
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pr_err("no memory for data\n");
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return NULL;
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}
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hdr = (struct nci_data_hdr *) skb_put(skb, NCI_DATA_HDR_SIZE);
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hdr->conn_id = NCI_CORE_LC_CONNID_PROP_FW_DL;
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hdr->rfu = 0;
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hdr->plen = plen;
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nci_mt_set((__u8 *)hdr, NCI_MT_DATA_PKT);
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nci_pbf_set((__u8 *)hdr, NCI_PBF_LAST);
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return skb;
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}
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static void fw_dnld_over(struct nfcmrvl_private *priv, u32 error)
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{
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if (priv->fw_dnld.fw) {
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release_firmware(priv->fw_dnld.fw);
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priv->fw_dnld.fw = NULL;
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priv->fw_dnld.header = NULL;
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priv->fw_dnld.binary_config = NULL;
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}
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atomic_set(&priv->ndev->cmd_cnt, 0);
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if (timer_pending(&priv->ndev->cmd_timer))
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del_timer_sync(&priv->ndev->cmd_timer);
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if (timer_pending(&priv->fw_dnld.timer))
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del_timer_sync(&priv->fw_dnld.timer);
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nfc_info(priv->dev, "FW loading over (%d)]\n", error);
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if (error != 0) {
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/* failed, halt the chip to avoid power consumption */
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nfcmrvl_chip_halt(priv);
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}
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nfc_fw_download_done(priv->ndev->nfc_dev, priv->fw_dnld.name, error);
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}
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static void fw_dnld_timeout(unsigned long arg)
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{
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struct nfcmrvl_private *priv = (struct nfcmrvl_private *) arg;
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nfc_err(priv->dev, "FW loading timeout");
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priv->fw_dnld.state = STATE_RESET;
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fw_dnld_over(priv, -ETIMEDOUT);
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}
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static int process_state_reset(struct nfcmrvl_private *priv,
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struct sk_buff *skb)
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{
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if (sizeof(nci_pattern_core_reset_ntf) != skb->len ||
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memcmp(skb->data, nci_pattern_core_reset_ntf,
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sizeof(nci_pattern_core_reset_ntf)))
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return -EINVAL;
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nfc_info(priv->dev, "BootROM reset, start fw download\n");
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/* Start FW download state machine */
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priv->fw_dnld.state = STATE_INIT;
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nci_send_cmd(priv->ndev, NCI_OP_CORE_INIT_CMD, 0, NULL);
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return 0;
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}
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static int process_state_init(struct nfcmrvl_private *priv, struct sk_buff *skb)
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{
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struct nci_core_set_config_cmd cmd;
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if (sizeof(nci_pattern_core_init_rsp) >= skb->len ||
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memcmp(skb->data, nci_pattern_core_init_rsp,
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sizeof(nci_pattern_core_init_rsp)))
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return -EINVAL;
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cmd.num_params = 1;
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cmd.param.id = NFCMRVL_PROP_REF_CLOCK;
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cmd.param.len = 4;
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memcpy(cmd.param.val, &priv->fw_dnld.header->ref_clock, 4);
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nci_send_cmd(priv->ndev, NCI_OP_CORE_SET_CONFIG_CMD, 3 + cmd.param.len,
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&cmd);
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priv->fw_dnld.state = STATE_SET_REF_CLOCK;
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return 0;
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}
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static void create_lc(struct nfcmrvl_private *priv)
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{
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uint8_t param[2] = { NCI_CORE_LC_PROP_FW_DL, 0x0 };
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priv->fw_dnld.state = STATE_OPEN_LC;
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nci_send_cmd(priv->ndev, NCI_OP_CORE_CONN_CREATE_CMD, 2, param);
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}
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static int process_state_set_ref_clock(struct nfcmrvl_private *priv,
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struct sk_buff *skb)
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{
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struct nci_core_set_config_cmd cmd;
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if (sizeof(nci_pattern_core_set_config_rsp) != skb->len ||
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memcmp(skb->data, nci_pattern_core_set_config_rsp, skb->len))
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return -EINVAL;
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cmd.num_params = 1;
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cmd.param.id = NFCMRVL_PROP_SET_HI_CONFIG;
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switch (priv->phy) {
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case NFCMRVL_PHY_UART:
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cmd.param.len = 5;
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memcpy(cmd.param.val,
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&priv->fw_dnld.binary_config->uart.baudrate,
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4);
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cmd.param.val[4] =
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priv->fw_dnld.binary_config->uart.flow_control;
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break;
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case NFCMRVL_PHY_I2C:
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cmd.param.len = 5;
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memcpy(cmd.param.val,
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&priv->fw_dnld.binary_config->i2c.clk,
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4);
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cmd.param.val[4] = 0;
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break;
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case NFCMRVL_PHY_SPI:
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cmd.param.len = 5;
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memcpy(cmd.param.val,
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&priv->fw_dnld.binary_config->spi.clk,
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4);
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cmd.param.val[4] = 0;
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break;
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default:
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create_lc(priv);
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return 0;
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}
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priv->fw_dnld.state = STATE_SET_HI_CONFIG;
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nci_send_cmd(priv->ndev, NCI_OP_CORE_SET_CONFIG_CMD, 3 + cmd.param.len,
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&cmd);
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return 0;
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}
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static int process_state_set_hi_config(struct nfcmrvl_private *priv,
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struct sk_buff *skb)
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{
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if (sizeof(nci_pattern_core_set_config_rsp) != skb->len ||
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memcmp(skb->data, nci_pattern_core_set_config_rsp, skb->len))
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return -EINVAL;
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create_lc(priv);
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return 0;
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}
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static int process_state_open_lc(struct nfcmrvl_private *priv,
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struct sk_buff *skb)
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{
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if (sizeof(nci_pattern_core_conn_create_rsp) >= skb->len ||
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memcmp(skb->data, nci_pattern_core_conn_create_rsp,
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sizeof(nci_pattern_core_conn_create_rsp)))
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return -EINVAL;
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priv->fw_dnld.state = STATE_FW_DNLD;
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priv->fw_dnld.substate = SUBSTATE_WAIT_COMMAND;
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priv->fw_dnld.offset = priv->fw_dnld.binary_config->offset;
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return 0;
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}
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static int process_state_fw_dnld(struct nfcmrvl_private *priv,
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struct sk_buff *skb)
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{
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uint16_t len;
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uint16_t comp_len;
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struct sk_buff *out_skb;
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switch (priv->fw_dnld.substate) {
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case SUBSTATE_WAIT_COMMAND:
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/*
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* Command format:
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* B0..2: NCI header
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* B3 : Helper command (0xA5)
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* B4..5: le16 data size
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* B6..7: le16 data size complement (~)
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* B8..N: payload
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*/
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/* Remove NCI HDR */
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skb_pull(skb, 3);
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if (skb->data[0] != HELPER_CMD_PACKET_FORMAT || skb->len != 5) {
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nfc_err(priv->dev, "bad command");
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return -EINVAL;
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}
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skb_pull(skb, 1);
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len = get_unaligned_le16(skb->data);
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skb_pull(skb, 2);
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comp_len = get_unaligned_le16(skb->data);
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memcpy(&comp_len, skb->data, 2);
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skb_pull(skb, 2);
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if (((~len) & 0xFFFF) != comp_len) {
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nfc_err(priv->dev, "bad len complement: %x %x %x",
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len, comp_len, (~len & 0xFFFF));
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out_skb = alloc_lc_skb(priv, 1);
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if (!out_skb)
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return -ENOMEM;
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*skb_put(out_skb, 1) = 0xBF;
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nci_send_frame(priv->ndev, out_skb);
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priv->fw_dnld.substate = SUBSTATE_WAIT_NACK_CREDIT;
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return 0;
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}
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priv->fw_dnld.chunk_len = len;
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out_skb = alloc_lc_skb(priv, 1);
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if (!out_skb)
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return -ENOMEM;
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*skb_put(out_skb, 1) = HELPER_ACK_PACKET_FORMAT;
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nci_send_frame(priv->ndev, out_skb);
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priv->fw_dnld.substate = SUBSTATE_WAIT_ACK_CREDIT;
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break;
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case SUBSTATE_WAIT_ACK_CREDIT:
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if (sizeof(nci_pattern_core_conn_credits_ntf) != skb->len ||
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memcmp(nci_pattern_core_conn_credits_ntf, skb->data,
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skb->len)) {
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nfc_err(priv->dev, "bad packet: waiting for credit");
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return -EINVAL;
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}
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if (priv->fw_dnld.chunk_len == 0) {
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/* FW Loading is done */
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uint8_t conn_id = NCI_CORE_LC_CONNID_PROP_FW_DL;
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priv->fw_dnld.state = STATE_CLOSE_LC;
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nci_send_cmd(priv->ndev, NCI_OP_CORE_CONN_CLOSE_CMD,
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1, &conn_id);
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} else {
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out_skb = alloc_lc_skb(priv, priv->fw_dnld.chunk_len);
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if (!out_skb)
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return -ENOMEM;
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memcpy(skb_put(out_skb, priv->fw_dnld.chunk_len),
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((uint8_t *)priv->fw_dnld.fw->data) +
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priv->fw_dnld.offset,
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priv->fw_dnld.chunk_len);
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nci_send_frame(priv->ndev, out_skb);
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priv->fw_dnld.substate = SUBSTATE_WAIT_DATA_CREDIT;
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}
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break;
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case SUBSTATE_WAIT_DATA_CREDIT:
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if (sizeof(nci_pattern_core_conn_credits_ntf) != skb->len ||
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memcmp(nci_pattern_core_conn_credits_ntf, skb->data,
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skb->len)) {
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nfc_err(priv->dev, "bad packet: waiting for credit");
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return -EINVAL;
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}
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priv->fw_dnld.offset += priv->fw_dnld.chunk_len;
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priv->fw_dnld.chunk_len = 0;
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priv->fw_dnld.substate = SUBSTATE_WAIT_COMMAND;
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break;
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case SUBSTATE_WAIT_NACK_CREDIT:
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if (sizeof(nci_pattern_core_conn_credits_ntf) != skb->len ||
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memcmp(nci_pattern_core_conn_credits_ntf, skb->data,
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skb->len)) {
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nfc_err(priv->dev, "bad packet: waiting for credit");
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return -EINVAL;
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}
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priv->fw_dnld.substate = SUBSTATE_WAIT_COMMAND;
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break;
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}
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return 0;
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}
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static int process_state_close_lc(struct nfcmrvl_private *priv,
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struct sk_buff *skb)
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{
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if (sizeof(nci_pattern_core_conn_close_rsp) != skb->len ||
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memcmp(skb->data, nci_pattern_core_conn_close_rsp, skb->len))
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return -EINVAL;
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priv->fw_dnld.state = STATE_BOOT;
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nci_send_cmd(priv->ndev, NCI_OP_PROPRIETARY_BOOT_CMD, 0, NULL);
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return 0;
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}
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static int process_state_boot(struct nfcmrvl_private *priv, struct sk_buff *skb)
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{
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if (sizeof(nci_pattern_proprietary_boot_rsp) != skb->len ||
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memcmp(skb->data, nci_pattern_proprietary_boot_rsp, skb->len))
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return -EINVAL;
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/*
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* Update HI config to use the right configuration for the next
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* data exchanges.
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*/
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priv->if_ops->nci_update_config(priv,
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&priv->fw_dnld.binary_config->config);
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if (priv->fw_dnld.binary_config == &priv->fw_dnld.header->helper) {
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/*
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* This is the case where an helper was needed and we have
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* uploaded it. Now we have to wait the next RESET NTF to start
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* FW download.
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*/
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priv->fw_dnld.state = STATE_RESET;
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priv->fw_dnld.binary_config = &priv->fw_dnld.header->firmware;
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nfc_info(priv->dev, "FW loading: helper loaded");
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} else {
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nfc_info(priv->dev, "FW loading: firmware loaded");
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fw_dnld_over(priv, 0);
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}
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return 0;
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}
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static void fw_dnld_rx_work(struct work_struct *work)
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{
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int ret;
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struct sk_buff *skb;
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struct nfcmrvl_fw_dnld *fw_dnld = container_of(work,
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struct nfcmrvl_fw_dnld,
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rx_work);
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struct nfcmrvl_private *priv = container_of(fw_dnld,
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struct nfcmrvl_private,
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fw_dnld);
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while ((skb = skb_dequeue(&fw_dnld->rx_q))) {
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nfc_send_to_raw_sock(priv->ndev->nfc_dev, skb,
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RAW_PAYLOAD_NCI, NFC_DIRECTION_RX);
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switch (fw_dnld->state) {
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case STATE_RESET:
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ret = process_state_reset(priv, skb);
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break;
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case STATE_INIT:
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ret = process_state_init(priv, skb);
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break;
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case STATE_SET_REF_CLOCK:
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ret = process_state_set_ref_clock(priv, skb);
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break;
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case STATE_SET_HI_CONFIG:
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ret = process_state_set_hi_config(priv, skb);
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break;
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case STATE_OPEN_LC:
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ret = process_state_open_lc(priv, skb);
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break;
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case STATE_FW_DNLD:
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ret = process_state_fw_dnld(priv, skb);
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break;
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case STATE_CLOSE_LC:
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ret = process_state_close_lc(priv, skb);
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break;
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case STATE_BOOT:
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ret = process_state_boot(priv, skb);
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break;
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default:
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ret = -EFAULT;
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}
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kfree_skb(skb);
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if (ret != 0) {
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nfc_err(priv->dev, "FW loading error");
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fw_dnld_over(priv, ret);
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break;
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}
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}
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}
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int nfcmrvl_fw_dnld_init(struct nfcmrvl_private *priv)
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{
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char name[32];
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INIT_WORK(&priv->fw_dnld.rx_work, fw_dnld_rx_work);
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snprintf(name, sizeof(name), "%s_nfcmrvl_fw_dnld_rx_wq",
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dev_name(priv->dev));
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priv->fw_dnld.rx_wq = create_singlethread_workqueue(name);
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if (!priv->fw_dnld.rx_wq)
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return -ENOMEM;
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skb_queue_head_init(&priv->fw_dnld.rx_q);
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return 0;
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}
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void nfcmrvl_fw_dnld_deinit(struct nfcmrvl_private *priv)
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{
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destroy_workqueue(priv->fw_dnld.rx_wq);
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}
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void nfcmrvl_fw_dnld_recv_frame(struct nfcmrvl_private *priv,
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struct sk_buff *skb)
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{
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/* Discard command timer */
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if (timer_pending(&priv->ndev->cmd_timer))
|
|
del_timer_sync(&priv->ndev->cmd_timer);
|
|
|
|
/* Allow next command */
|
|
atomic_set(&priv->ndev->cmd_cnt, 1);
|
|
|
|
/* Queue and trigger rx work */
|
|
skb_queue_tail(&priv->fw_dnld.rx_q, skb);
|
|
queue_work(priv->fw_dnld.rx_wq, &priv->fw_dnld.rx_work);
|
|
}
|
|
|
|
void nfcmrvl_fw_dnld_abort(struct nfcmrvl_private *priv)
|
|
{
|
|
fw_dnld_over(priv, -EHOSTDOWN);
|
|
}
|
|
|
|
int nfcmrvl_fw_dnld_start(struct nci_dev *ndev, const char *firmware_name)
|
|
{
|
|
struct nfcmrvl_private *priv = nci_get_drvdata(ndev);
|
|
struct nfcmrvl_fw_dnld *fw_dnld = &priv->fw_dnld;
|
|
|
|
if (!priv->support_fw_dnld)
|
|
return -ENOTSUPP;
|
|
|
|
if (!firmware_name || !firmware_name[0])
|
|
return -EINVAL;
|
|
|
|
strcpy(fw_dnld->name, firmware_name);
|
|
|
|
/*
|
|
* Retrieve FW binary file and parse it to initialize FW download
|
|
* state machine.
|
|
*/
|
|
|
|
/* Retrieve FW binary */
|
|
if (request_firmware(&fw_dnld->fw, firmware_name, priv->dev) < 0) {
|
|
nfc_err(priv->dev, "failed to retrieve FW %s", firmware_name);
|
|
return -ENOENT;
|
|
}
|
|
|
|
fw_dnld->header = (const struct nfcmrvl_fw *) priv->fw_dnld.fw->data;
|
|
|
|
if (fw_dnld->header->magic != NFCMRVL_FW_MAGIC ||
|
|
fw_dnld->header->phy != priv->phy) {
|
|
nfc_err(priv->dev, "bad firmware binary %s magic=0x%x phy=%d",
|
|
firmware_name, fw_dnld->header->magic,
|
|
fw_dnld->header->phy);
|
|
release_firmware(fw_dnld->fw);
|
|
fw_dnld->header = NULL;
|
|
return -EINVAL;
|
|
}
|
|
|
|
if (fw_dnld->header->helper.offset != 0) {
|
|
nfc_info(priv->dev, "loading helper");
|
|
fw_dnld->binary_config = &fw_dnld->header->helper;
|
|
} else {
|
|
nfc_info(priv->dev, "loading firmware");
|
|
fw_dnld->binary_config = &fw_dnld->header->firmware;
|
|
}
|
|
|
|
/* Configure a timer for timeout */
|
|
setup_timer(&priv->fw_dnld.timer, fw_dnld_timeout,
|
|
(unsigned long) priv);
|
|
mod_timer(&priv->fw_dnld.timer,
|
|
jiffies + msecs_to_jiffies(FW_DNLD_TIMEOUT));
|
|
|
|
/* Ronfigure HI to be sure that it is the bootrom values */
|
|
priv->if_ops->nci_update_config(priv,
|
|
&fw_dnld->header->bootrom.config);
|
|
|
|
/* Allow first command */
|
|
atomic_set(&priv->ndev->cmd_cnt, 1);
|
|
|
|
/* First, reset the chip */
|
|
priv->fw_dnld.state = STATE_RESET;
|
|
nfcmrvl_chip_reset(priv);
|
|
|
|
/* Now wait for CORE_RESET_NTF or timeout */
|
|
|
|
return 0;
|
|
}
|