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 int reset_n_io = -EINVAL; 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_get_compatible_child(node, "marvell,nfc-uart"); 77 if (!matched_node) { 78 matched_node = of_get_compatible_child(node, "mrvl,nfc-uart"); 79 if (!matched_node) 80 return -ENODEV; 81 } 82 83 ret = nfcmrvl_parse_dt(matched_node, pdata); 84 if (ret < 0) { 85 pr_err("Failed to get generic entries\n"); 86 of_node_put(matched_node); 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 of_node_put(matched_node); 101 102 return 0; 103 } 104 105 /* 106 ** NCI UART OPS 107 */ 108 109 static int nfcmrvl_nci_uart_open(struct nci_uart *nu) 110 { 111 struct nfcmrvl_private *priv; 112 struct nfcmrvl_platform_data *pdata = NULL; 113 struct nfcmrvl_platform_data config; 114 struct device *dev = nu->tty->dev; 115 116 /* 117 * Platform data cannot be used here since usually it is already used 118 * by low level serial driver. We can try to retrieve serial device 119 * and check if DT entries were added. 120 */ 121 122 if (dev && dev->parent && dev->parent->of_node) 123 if (nfcmrvl_uart_parse_dt(dev->parent->of_node, &config) == 0) 124 pdata = &config; 125 126 if (!pdata) { 127 pr_info("No platform data / DT -> fallback to module params\n"); 128 config.hci_muxed = hci_muxed; 129 config.reset_n_io = reset_n_io; 130 config.flow_control = flow_control; 131 config.break_control = break_control; 132 pdata = &config; 133 } 134 135 priv = nfcmrvl_nci_register_dev(NFCMRVL_PHY_UART, nu, &uart_ops, 136 dev, pdata); 137 if (IS_ERR(priv)) 138 return PTR_ERR(priv); 139 140 priv->support_fw_dnld = true; 141 142 nu->drv_data = priv; 143 nu->ndev = priv->ndev; 144 145 return 0; 146 } 147 148 static void nfcmrvl_nci_uart_close(struct nci_uart *nu) 149 { 150 nfcmrvl_nci_unregister_dev((struct nfcmrvl_private *)nu->drv_data); 151 } 152 153 static int nfcmrvl_nci_uart_recv(struct nci_uart *nu, struct sk_buff *skb) 154 { 155 return nfcmrvl_nci_recv_frame((struct nfcmrvl_private *)nu->drv_data, 156 skb); 157 } 158 159 static void nfcmrvl_nci_uart_tx_start(struct nci_uart *nu) 160 { 161 struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data; 162 163 if (priv->ndev->nfc_dev->fw_download_in_progress) 164 return; 165 166 /* Remove BREAK to wake up the NFCC */ 167 if (priv->config.break_control && nu->tty->ops->break_ctl) { 168 nu->tty->ops->break_ctl(nu->tty, 0); 169 usleep_range(3000, 5000); 170 } 171 } 172 173 static void nfcmrvl_nci_uart_tx_done(struct nci_uart *nu) 174 { 175 struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data; 176 177 if (priv->ndev->nfc_dev->fw_download_in_progress) 178 return; 179 180 /* 181 ** To ensure that if the NFCC goes in DEEP SLEEP sate we can wake him 182 ** up. we set BREAK. Once we will be ready to send again we will remove 183 ** it. 184 */ 185 if (priv->config.break_control && nu->tty->ops->break_ctl) { 186 nu->tty->ops->break_ctl(nu->tty, -1); 187 usleep_range(1000, 3000); 188 } 189 } 190 191 static struct nci_uart nfcmrvl_nci_uart = { 192 .owner = THIS_MODULE, 193 .name = "nfcmrvl_uart", 194 .driver = NCI_UART_DRIVER_MARVELL, 195 .ops = { 196 .open = nfcmrvl_nci_uart_open, 197 .close = nfcmrvl_nci_uart_close, 198 .recv = nfcmrvl_nci_uart_recv, 199 .tx_start = nfcmrvl_nci_uart_tx_start, 200 .tx_done = nfcmrvl_nci_uart_tx_done, 201 } 202 }; 203 204 /* 205 ** Module init 206 */ 207 208 static int nfcmrvl_uart_init_module(void) 209 { 210 return nci_uart_register(&nfcmrvl_nci_uart); 211 } 212 213 static void nfcmrvl_uart_exit_module(void) 214 { 215 nci_uart_unregister(&nfcmrvl_nci_uart); 216 } 217 218 module_init(nfcmrvl_uart_init_module); 219 module_exit(nfcmrvl_uart_exit_module); 220 221 MODULE_AUTHOR("Marvell International Ltd."); 222 MODULE_DESCRIPTION("Marvell NFC-over-UART"); 223 MODULE_LICENSE("GPL v2"); 224 225 module_param(flow_control, uint, 0); 226 MODULE_PARM_DESC(flow_control, "Tell if UART needs flow control at init."); 227 228 module_param(break_control, uint, 0); 229 MODULE_PARM_DESC(break_control, "Tell if UART driver must drive break signal."); 230 231 module_param(hci_muxed, uint, 0); 232 MODULE_PARM_DESC(hci_muxed, "Tell if transport is muxed in HCI one."); 233 234 module_param(reset_n_io, int, 0); 235 MODULE_PARM_DESC(reset_n_io, "GPIO that is wired to RESET_N signal."); 236