1 /** 2 * Marvell NFC-over-UART driver 3 * 4 * Copyright (C) 2015, Marvell International Ltd. 5 * 6 * This software file (the "File") is distributed by Marvell International 7 * Ltd. under the terms of the GNU General Public License Version 2, June 1991 8 * (the "License"). You may use, redistribute and/or modify this File in 9 * accordance with the terms and conditions of the License, a copy of which 10 * is available on the worldwide web at 11 * http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt. 12 * 13 * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE 14 * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE 15 * ARE EXPRESSLY DISCLAIMED. The License provides additional details about 16 * this warranty disclaimer. 17 */ 18 19 #include <linux/module.h> 20 #include <linux/delay.h> 21 #include <linux/of_gpio.h> 22 #include <net/nfc/nci.h> 23 #include <net/nfc/nci_core.h> 24 #include "nfcmrvl.h" 25 26 static unsigned int hci_muxed; 27 static unsigned int flow_control; 28 static unsigned int break_control; 29 static unsigned int reset_n_io; 30 31 /* 32 ** NFCMRVL NCI OPS 33 */ 34 35 static int nfcmrvl_uart_nci_open(struct nfcmrvl_private *priv) 36 { 37 return 0; 38 } 39 40 static int nfcmrvl_uart_nci_close(struct nfcmrvl_private *priv) 41 { 42 return 0; 43 } 44 45 static int nfcmrvl_uart_nci_send(struct nfcmrvl_private *priv, 46 struct sk_buff *skb) 47 { 48 struct nci_uart *nu = priv->drv_data; 49 50 return nu->ops.send(nu, skb); 51 } 52 53 static void nfcmrvl_uart_nci_update_config(struct nfcmrvl_private *priv, 54 const void *param) 55 { 56 struct nci_uart *nu = priv->drv_data; 57 const struct nfcmrvl_fw_uart_config *config = param; 58 59 nci_uart_set_config(nu, le32_to_cpu(config->baudrate), 60 config->flow_control); 61 } 62 63 static struct nfcmrvl_if_ops uart_ops = { 64 .nci_open = nfcmrvl_uart_nci_open, 65 .nci_close = nfcmrvl_uart_nci_close, 66 .nci_send = nfcmrvl_uart_nci_send, 67 .nci_update_config = nfcmrvl_uart_nci_update_config 68 }; 69 70 static int nfcmrvl_uart_parse_dt(struct device_node *node, 71 struct nfcmrvl_platform_data *pdata) 72 { 73 struct device_node *matched_node; 74 int ret; 75 76 matched_node = of_find_compatible_node(node, NULL, "marvell,nfc-uart"); 77 if (!matched_node) { 78 matched_node = of_find_compatible_node(node, NULL, 79 "mrvl,nfc-uart"); 80 if (!matched_node) 81 return -ENODEV; 82 } 83 84 ret = nfcmrvl_parse_dt(matched_node, pdata); 85 if (ret < 0) { 86 pr_err("Failed to get generic entries\n"); 87 return ret; 88 } 89 90 if (of_find_property(matched_node, "flow-control", NULL)) 91 pdata->flow_control = 1; 92 else 93 pdata->flow_control = 0; 94 95 if (of_find_property(matched_node, "break-control", NULL)) 96 pdata->break_control = 1; 97 else 98 pdata->break_control = 0; 99 100 return 0; 101 } 102 103 /* 104 ** NCI UART OPS 105 */ 106 107 static int nfcmrvl_nci_uart_open(struct nci_uart *nu) 108 { 109 struct nfcmrvl_private *priv; 110 struct nfcmrvl_platform_data *pdata = NULL; 111 struct nfcmrvl_platform_data config; 112 113 /* 114 * Platform data cannot be used here since usually it is already used 115 * by low level serial driver. We can try to retrieve serial device 116 * and check if DT entries were added. 117 */ 118 119 if (nu->tty->dev->parent && nu->tty->dev->parent->of_node) 120 if (nfcmrvl_uart_parse_dt(nu->tty->dev->parent->of_node, 121 &config) == 0) 122 pdata = &config; 123 124 if (!pdata) { 125 pr_info("No platform data / DT -> fallback to module params\n"); 126 config.hci_muxed = hci_muxed; 127 config.reset_n_io = reset_n_io; 128 config.flow_control = flow_control; 129 config.break_control = break_control; 130 pdata = &config; 131 } 132 133 priv = nfcmrvl_nci_register_dev(NFCMRVL_PHY_UART, nu, &uart_ops, 134 nu->tty->dev, pdata); 135 if (IS_ERR(priv)) 136 return PTR_ERR(priv); 137 138 priv->support_fw_dnld = true; 139 140 nu->drv_data = priv; 141 nu->ndev = priv->ndev; 142 143 return 0; 144 } 145 146 static void nfcmrvl_nci_uart_close(struct nci_uart *nu) 147 { 148 nfcmrvl_nci_unregister_dev((struct nfcmrvl_private *)nu->drv_data); 149 } 150 151 static int nfcmrvl_nci_uart_recv(struct nci_uart *nu, struct sk_buff *skb) 152 { 153 return nfcmrvl_nci_recv_frame((struct nfcmrvl_private *)nu->drv_data, 154 skb); 155 } 156 157 static void nfcmrvl_nci_uart_tx_start(struct nci_uart *nu) 158 { 159 struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data; 160 161 if (priv->ndev->nfc_dev->fw_download_in_progress) 162 return; 163 164 /* Remove BREAK to wake up the NFCC */ 165 if (priv->config.break_control && nu->tty->ops->break_ctl) { 166 nu->tty->ops->break_ctl(nu->tty, 0); 167 usleep_range(3000, 5000); 168 } 169 } 170 171 static void nfcmrvl_nci_uart_tx_done(struct nci_uart *nu) 172 { 173 struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data; 174 175 if (priv->ndev->nfc_dev->fw_download_in_progress) 176 return; 177 178 /* 179 ** To ensure that if the NFCC goes in DEEP SLEEP sate we can wake him 180 ** up. we set BREAK. Once we will be ready to send again we will remove 181 ** it. 182 */ 183 if (priv->config.break_control && nu->tty->ops->break_ctl) { 184 nu->tty->ops->break_ctl(nu->tty, -1); 185 usleep_range(1000, 3000); 186 } 187 } 188 189 static struct nci_uart nfcmrvl_nci_uart = { 190 .owner = THIS_MODULE, 191 .name = "nfcmrvl_uart", 192 .driver = NCI_UART_DRIVER_MARVELL, 193 .ops = { 194 .open = nfcmrvl_nci_uart_open, 195 .close = nfcmrvl_nci_uart_close, 196 .recv = nfcmrvl_nci_uart_recv, 197 .tx_start = nfcmrvl_nci_uart_tx_start, 198 .tx_done = nfcmrvl_nci_uart_tx_done, 199 } 200 }; 201 202 /* 203 ** Module init 204 */ 205 206 static int nfcmrvl_uart_init_module(void) 207 { 208 return nci_uart_register(&nfcmrvl_nci_uart); 209 } 210 211 static void nfcmrvl_uart_exit_module(void) 212 { 213 nci_uart_unregister(&nfcmrvl_nci_uart); 214 } 215 216 module_init(nfcmrvl_uart_init_module); 217 module_exit(nfcmrvl_uart_exit_module); 218 219 MODULE_AUTHOR("Marvell International Ltd."); 220 MODULE_DESCRIPTION("Marvell NFC-over-UART"); 221 MODULE_LICENSE("GPL v2"); 222 223 module_param(flow_control, uint, 0); 224 MODULE_PARM_DESC(flow_control, "Tell if UART needs flow control at init."); 225 226 module_param(break_control, uint, 0); 227 MODULE_PARM_DESC(break_control, "Tell if UART driver must drive break signal."); 228 229 module_param(hci_muxed, uint, 0); 230 MODULE_PARM_DESC(hci_muxed, "Tell if transport is muxed in HCI one."); 231 232 module_param(reset_n_io, uint, 0); 233 MODULE_PARM_DESC(reset_n_io, "GPIO that is wired to RESET_N signal."); 234