1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Marvell NFC-over-UART driver 4 * 5 * Copyright (C) 2015, Marvell International Ltd. 6 */ 7 8 #include <linux/module.h> 9 #include <linux/delay.h> 10 #include <linux/of_gpio.h> 11 #include <net/nfc/nci.h> 12 #include <net/nfc/nci_core.h> 13 #include "nfcmrvl.h" 14 15 static unsigned int hci_muxed; 16 static unsigned int flow_control; 17 static unsigned int break_control; 18 static int reset_n_io = -EINVAL; 19 20 /* 21 * NFCMRVL NCI OPS 22 */ 23 24 static int nfcmrvl_uart_nci_open(struct nfcmrvl_private *priv) 25 { 26 return 0; 27 } 28 29 static int nfcmrvl_uart_nci_close(struct nfcmrvl_private *priv) 30 { 31 return 0; 32 } 33 34 static int nfcmrvl_uart_nci_send(struct nfcmrvl_private *priv, 35 struct sk_buff *skb) 36 { 37 struct nci_uart *nu = priv->drv_data; 38 39 return nu->ops.send(nu, skb); 40 } 41 42 static void nfcmrvl_uart_nci_update_config(struct nfcmrvl_private *priv, 43 const void *param) 44 { 45 struct nci_uart *nu = priv->drv_data; 46 const struct nfcmrvl_fw_uart_config *config = param; 47 48 nci_uart_set_config(nu, le32_to_cpu(config->baudrate), 49 config->flow_control); 50 } 51 52 static const struct nfcmrvl_if_ops uart_ops = { 53 .nci_open = nfcmrvl_uart_nci_open, 54 .nci_close = nfcmrvl_uart_nci_close, 55 .nci_send = nfcmrvl_uart_nci_send, 56 .nci_update_config = nfcmrvl_uart_nci_update_config 57 }; 58 59 static int nfcmrvl_uart_parse_dt(struct device_node *node, 60 struct nfcmrvl_platform_data *pdata) 61 { 62 struct device_node *matched_node; 63 int ret; 64 65 matched_node = of_get_compatible_child(node, "marvell,nfc-uart"); 66 if (!matched_node) { 67 matched_node = of_get_compatible_child(node, "mrvl,nfc-uart"); 68 if (!matched_node) 69 return -ENODEV; 70 } 71 72 ret = nfcmrvl_parse_dt(matched_node, pdata); 73 if (ret < 0) { 74 pr_err("Failed to get generic entries\n"); 75 of_node_put(matched_node); 76 return ret; 77 } 78 79 if (of_find_property(matched_node, "flow-control", NULL)) 80 pdata->flow_control = 1; 81 else 82 pdata->flow_control = 0; 83 84 if (of_find_property(matched_node, "break-control", NULL)) 85 pdata->break_control = 1; 86 else 87 pdata->break_control = 0; 88 89 of_node_put(matched_node); 90 91 return 0; 92 } 93 94 /* 95 * NCI UART OPS 96 */ 97 98 static int nfcmrvl_nci_uart_open(struct nci_uart *nu) 99 { 100 struct nfcmrvl_private *priv; 101 struct nfcmrvl_platform_data config; 102 const struct nfcmrvl_platform_data *pdata = NULL; 103 struct device *dev = nu->tty->dev; 104 105 /* 106 * Platform data cannot be used here since usually it is already used 107 * by low level serial driver. We can try to retrieve serial device 108 * and check if DT entries were added. 109 */ 110 111 if (dev && dev->parent && dev->parent->of_node) 112 if (nfcmrvl_uart_parse_dt(dev->parent->of_node, &config) == 0) 113 pdata = &config; 114 115 if (!pdata) { 116 pr_info("No platform data / DT -> fallback to module params\n"); 117 config.hci_muxed = hci_muxed; 118 config.reset_n_io = reset_n_io; 119 config.flow_control = flow_control; 120 config.break_control = break_control; 121 pdata = &config; 122 } 123 124 priv = nfcmrvl_nci_register_dev(NFCMRVL_PHY_UART, nu, &uart_ops, 125 dev, pdata); 126 if (IS_ERR(priv)) 127 return PTR_ERR(priv); 128 129 priv->support_fw_dnld = true; 130 131 nu->drv_data = priv; 132 nu->ndev = priv->ndev; 133 134 return 0; 135 } 136 137 static void nfcmrvl_nci_uart_close(struct nci_uart *nu) 138 { 139 nfcmrvl_nci_unregister_dev((struct nfcmrvl_private *)nu->drv_data); 140 } 141 142 static int nfcmrvl_nci_uart_recv(struct nci_uart *nu, struct sk_buff *skb) 143 { 144 return nfcmrvl_nci_recv_frame((struct nfcmrvl_private *)nu->drv_data, 145 skb); 146 } 147 148 static void nfcmrvl_nci_uart_tx_start(struct nci_uart *nu) 149 { 150 struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data; 151 152 if (priv->ndev->nfc_dev->fw_download_in_progress) 153 return; 154 155 /* Remove BREAK to wake up the NFCC */ 156 if (priv->config.break_control && nu->tty->ops->break_ctl) { 157 nu->tty->ops->break_ctl(nu->tty, 0); 158 usleep_range(3000, 5000); 159 } 160 } 161 162 static void nfcmrvl_nci_uart_tx_done(struct nci_uart *nu) 163 { 164 struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data; 165 166 if (priv->ndev->nfc_dev->fw_download_in_progress) 167 return; 168 169 /* 170 * To ensure that if the NFCC goes in DEEP SLEEP sate we can wake him 171 * up. we set BREAK. Once we will be ready to send again we will remove 172 * it. 173 */ 174 if (priv->config.break_control && nu->tty->ops->break_ctl) { 175 nu->tty->ops->break_ctl(nu->tty, -1); 176 usleep_range(1000, 3000); 177 } 178 } 179 180 static struct nci_uart nfcmrvl_nci_uart = { 181 .owner = THIS_MODULE, 182 .name = "nfcmrvl_uart", 183 .driver = NCI_UART_DRIVER_MARVELL, 184 .ops = { 185 .open = nfcmrvl_nci_uart_open, 186 .close = nfcmrvl_nci_uart_close, 187 .recv = nfcmrvl_nci_uart_recv, 188 .tx_start = nfcmrvl_nci_uart_tx_start, 189 .tx_done = nfcmrvl_nci_uart_tx_done, 190 } 191 }; 192 module_driver(nfcmrvl_nci_uart, nci_uart_register, nci_uart_unregister); 193 194 MODULE_AUTHOR("Marvell International Ltd."); 195 MODULE_DESCRIPTION("Marvell NFC-over-UART"); 196 MODULE_LICENSE("GPL v2"); 197 198 module_param(flow_control, uint, 0); 199 MODULE_PARM_DESC(flow_control, "Tell if UART needs flow control at init."); 200 201 module_param(break_control, uint, 0); 202 MODULE_PARM_DESC(break_control, "Tell if UART driver must drive break signal."); 203 204 module_param(hci_muxed, uint, 0); 205 MODULE_PARM_DESC(hci_muxed, "Tell if transport is muxed in HCI one."); 206 207 module_param(reset_n_io, int, 0); 208 MODULE_PARM_DESC(reset_n_io, "GPIO that is wired to RESET_N signal."); 209