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/delay.h> 9 #include <linux/device.h> 10 #include <linux/err.h> 11 #include <linux/gpio/consumer.h> 12 #include <linux/module.h> 13 #include <linux/of.h> 14 #include <linux/printk.h> 15 16 #include <net/nfc/nci.h> 17 #include <net/nfc/nci_core.h> 18 19 #include "nfcmrvl.h" 20 21 static unsigned int hci_muxed; 22 static unsigned int flow_control; 23 static unsigned int break_control; 24 25 /* 26 * NFCMRVL NCI OPS 27 */ 28 29 static int nfcmrvl_uart_nci_open(struct nfcmrvl_private *priv) 30 { 31 return 0; 32 } 33 34 static int nfcmrvl_uart_nci_close(struct nfcmrvl_private *priv) 35 { 36 return 0; 37 } 38 39 static int nfcmrvl_uart_nci_send(struct nfcmrvl_private *priv, 40 struct sk_buff *skb) 41 { 42 struct nci_uart *nu = priv->drv_data; 43 44 return nu->ops.send(nu, skb); 45 } 46 47 static void nfcmrvl_uart_nci_update_config(struct nfcmrvl_private *priv, 48 const void *param) 49 { 50 struct nci_uart *nu = priv->drv_data; 51 const struct nfcmrvl_fw_uart_config *config = param; 52 53 nci_uart_set_config(nu, le32_to_cpu(config->baudrate), 54 config->flow_control); 55 } 56 57 static const struct nfcmrvl_if_ops uart_ops = { 58 .nci_open = nfcmrvl_uart_nci_open, 59 .nci_close = nfcmrvl_uart_nci_close, 60 .nci_send = nfcmrvl_uart_nci_send, 61 .nci_update_config = nfcmrvl_uart_nci_update_config 62 }; 63 64 static int nfcmrvl_uart_parse_dt(struct device_node *node, 65 struct nfcmrvl_platform_data *pdata, 66 struct device *dev) 67 { 68 struct device_node *matched_node; 69 struct gpio_desc *reset_gpio; 70 int ret; 71 72 matched_node = of_get_compatible_child(node, "marvell,nfc-uart"); 73 if (!matched_node) { 74 matched_node = of_get_compatible_child(node, "mrvl,nfc-uart"); 75 if (!matched_node) 76 return -ENODEV; 77 } 78 79 ret = nfcmrvl_parse_dt(matched_node, pdata); 80 if (ret < 0) { 81 pr_err("Failed to get generic entries\n"); 82 of_node_put(matched_node); 83 return ret; 84 } 85 86 pdata->flow_control = of_property_read_bool(matched_node, "flow-control"); 87 pdata->break_control = of_property_read_bool(matched_node, "break-control"); 88 89 reset_gpio = devm_fwnode_gpiod_get_optional(dev, 90 of_fwnode_handle(matched_node), 91 "reset", GPIOD_OUT_HIGH, 92 "nfcmrvl_reset_n"); 93 if (IS_ERR(reset_gpio)) { 94 of_node_put(matched_node); 95 return PTR_ERR(reset_gpio); 96 } 97 pdata->reset_gpio = reset_gpio; 98 99 of_node_put(matched_node); 100 101 return 0; 102 } 103 104 /* 105 * NCI UART OPS 106 */ 107 108 static int nfcmrvl_nci_uart_open(struct nci_uart *nu) 109 { 110 struct nfcmrvl_private *priv; 111 struct nfcmrvl_platform_data config; 112 const struct nfcmrvl_platform_data *pdata = NULL; 113 struct device *dev = nu->tty->dev; 114 115 /* 116 * Platform data cannot be used here since usually it is already used 117 * by low level serial driver. We can try to retrieve serial device 118 * and check if DT entries were added. 119 */ 120 121 if (dev && dev->parent && dev->parent->of_node) 122 if (nfcmrvl_uart_parse_dt(dev->parent->of_node, &config, dev) == 0) 123 pdata = &config; 124 125 if (!pdata) { 126 pr_info("No platform data / DT -> fallback to module params\n"); 127 config.hci_muxed = hci_muxed; 128 config.reset_gpio = NULL; 129 config.flow_control = flow_control; 130 config.break_control = break_control; 131 pdata = &config; 132 } 133 134 priv = nfcmrvl_nci_register_dev(NFCMRVL_PHY_UART, nu, &uart_ops, 135 dev, pdata); 136 if (IS_ERR(priv)) 137 return PTR_ERR(priv); 138 139 priv->support_fw_dnld = true; 140 141 nu->drv_data = priv; 142 nu->ndev = priv->ndev; 143 144 return 0; 145 } 146 147 static void nfcmrvl_nci_uart_close(struct nci_uart *nu) 148 { 149 nfcmrvl_nci_unregister_dev((struct nfcmrvl_private *)nu->drv_data); 150 } 151 152 static int nfcmrvl_nci_uart_recv(struct nci_uart *nu, struct sk_buff *skb) 153 { 154 return nfcmrvl_nci_recv_frame((struct nfcmrvl_private *)nu->drv_data, 155 skb); 156 } 157 158 static void nfcmrvl_nci_uart_tx_start(struct nci_uart *nu) 159 { 160 struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data; 161 162 if (priv->ndev->nfc_dev->fw_download_in_progress) 163 return; 164 165 /* Remove BREAK to wake up the NFCC */ 166 if (priv->config.break_control && nu->tty->ops->break_ctl) { 167 nu->tty->ops->break_ctl(nu->tty, 0); 168 usleep_range(3000, 5000); 169 } 170 } 171 172 static void nfcmrvl_nci_uart_tx_done(struct nci_uart *nu) 173 { 174 struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data; 175 176 if (priv->ndev->nfc_dev->fw_download_in_progress) 177 return; 178 179 /* 180 * To ensure that if the NFCC goes in DEEP SLEEP sate we can wake him 181 * up. we set BREAK. Once we will be ready to send again we will remove 182 * it. 183 */ 184 if (priv->config.break_control && nu->tty->ops->break_ctl) { 185 nu->tty->ops->break_ctl(nu->tty, -1); 186 usleep_range(1000, 3000); 187 } 188 } 189 190 static struct nci_uart nfcmrvl_nci_uart = { 191 .owner = THIS_MODULE, 192 .name = "nfcmrvl_uart", 193 .driver = NCI_UART_DRIVER_MARVELL, 194 .ops = { 195 .open = nfcmrvl_nci_uart_open, 196 .close = nfcmrvl_nci_uart_close, 197 .recv = nfcmrvl_nci_uart_recv, 198 .tx_start = nfcmrvl_nci_uart_tx_start, 199 .tx_done = nfcmrvl_nci_uart_tx_done, 200 } 201 }; 202 module_driver(nfcmrvl_nci_uart, nci_uart_register, nci_uart_unregister); 203 204 MODULE_AUTHOR("Marvell International Ltd."); 205 MODULE_DESCRIPTION("Marvell NFC-over-UART"); 206 MODULE_LICENSE("GPL v2"); 207 208 module_param(flow_control, uint, 0); 209 MODULE_PARM_DESC(flow_control, "Tell if UART needs flow control at init."); 210 211 module_param(break_control, uint, 0); 212 MODULE_PARM_DESC(break_control, "Tell if UART driver must drive break signal."); 213 214 module_param(hci_muxed, uint, 0); 215 MODULE_PARM_DESC(hci_muxed, "Tell if transport is muxed in HCI one."); 216