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 of_node_put(matched_node); 88 return ret; 89 } 90 91 if (of_find_property(matched_node, "flow-control", NULL)) 92 pdata->flow_control = 1; 93 else 94 pdata->flow_control = 0; 95 96 if (of_find_property(matched_node, "break-control", NULL)) 97 pdata->break_control = 1; 98 else 99 pdata->break_control = 0; 100 101 of_node_put(matched_node); 102 103 return 0; 104 } 105 106 /* 107 ** NCI UART OPS 108 */ 109 110 static int nfcmrvl_nci_uart_open(struct nci_uart *nu) 111 { 112 struct nfcmrvl_private *priv; 113 struct nfcmrvl_platform_data *pdata = NULL; 114 struct nfcmrvl_platform_data config; 115 struct device *dev = nu->tty->dev; 116 117 /* 118 * Platform data cannot be used here since usually it is already used 119 * by low level serial driver. We can try to retrieve serial device 120 * and check if DT entries were added. 121 */ 122 123 if (dev && dev->parent && dev->parent->of_node) 124 if (nfcmrvl_uart_parse_dt(dev->parent->of_node, &config) == 0) 125 pdata = &config; 126 127 if (!pdata) { 128 pr_info("No platform data / DT -> fallback to module params\n"); 129 config.hci_muxed = hci_muxed; 130 config.reset_n_io = reset_n_io; 131 config.flow_control = flow_control; 132 config.break_control = break_control; 133 pdata = &config; 134 } 135 136 priv = nfcmrvl_nci_register_dev(NFCMRVL_PHY_UART, nu, &uart_ops, 137 dev, pdata); 138 if (IS_ERR(priv)) 139 return PTR_ERR(priv); 140 141 priv->support_fw_dnld = true; 142 143 nu->drv_data = priv; 144 nu->ndev = priv->ndev; 145 146 return 0; 147 } 148 149 static void nfcmrvl_nci_uart_close(struct nci_uart *nu) 150 { 151 nfcmrvl_nci_unregister_dev((struct nfcmrvl_private *)nu->drv_data); 152 } 153 154 static int nfcmrvl_nci_uart_recv(struct nci_uart *nu, struct sk_buff *skb) 155 { 156 return nfcmrvl_nci_recv_frame((struct nfcmrvl_private *)nu->drv_data, 157 skb); 158 } 159 160 static void nfcmrvl_nci_uart_tx_start(struct nci_uart *nu) 161 { 162 struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data; 163 164 if (priv->ndev->nfc_dev->fw_download_in_progress) 165 return; 166 167 /* Remove BREAK to wake up the NFCC */ 168 if (priv->config.break_control && nu->tty->ops->break_ctl) { 169 nu->tty->ops->break_ctl(nu->tty, 0); 170 usleep_range(3000, 5000); 171 } 172 } 173 174 static void nfcmrvl_nci_uart_tx_done(struct nci_uart *nu) 175 { 176 struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data; 177 178 if (priv->ndev->nfc_dev->fw_download_in_progress) 179 return; 180 181 /* 182 ** To ensure that if the NFCC goes in DEEP SLEEP sate we can wake him 183 ** up. we set BREAK. Once we will be ready to send again we will remove 184 ** it. 185 */ 186 if (priv->config.break_control && nu->tty->ops->break_ctl) { 187 nu->tty->ops->break_ctl(nu->tty, -1); 188 usleep_range(1000, 3000); 189 } 190 } 191 192 static struct nci_uart nfcmrvl_nci_uart = { 193 .owner = THIS_MODULE, 194 .name = "nfcmrvl_uart", 195 .driver = NCI_UART_DRIVER_MARVELL, 196 .ops = { 197 .open = nfcmrvl_nci_uart_open, 198 .close = nfcmrvl_nci_uart_close, 199 .recv = nfcmrvl_nci_uart_recv, 200 .tx_start = nfcmrvl_nci_uart_tx_start, 201 .tx_done = nfcmrvl_nci_uart_tx_done, 202 } 203 }; 204 205 /* 206 ** Module init 207 */ 208 209 static int nfcmrvl_uart_init_module(void) 210 { 211 return nci_uart_register(&nfcmrvl_nci_uart); 212 } 213 214 static void nfcmrvl_uart_exit_module(void) 215 { 216 nci_uart_unregister(&nfcmrvl_nci_uart); 217 } 218 219 module_init(nfcmrvl_uart_init_module); 220 module_exit(nfcmrvl_uart_exit_module); 221 222 MODULE_AUTHOR("Marvell International Ltd."); 223 MODULE_DESCRIPTION("Marvell NFC-over-UART"); 224 MODULE_LICENSE("GPL v2"); 225 226 module_param(flow_control, uint, 0); 227 MODULE_PARM_DESC(flow_control, "Tell if UART needs flow control at init."); 228 229 module_param(break_control, uint, 0); 230 MODULE_PARM_DESC(break_control, "Tell if UART driver must drive break signal."); 231 232 module_param(hci_muxed, uint, 0); 233 MODULE_PARM_DESC(hci_muxed, "Tell if transport is muxed in HCI one."); 234 235 module_param(reset_n_io, uint, 0); 236 MODULE_PARM_DESC(reset_n_io, "GPIO that is wired to RESET_N signal."); 237