diff options
Diffstat (limited to 'drivers/nfc/nfcmrvl/uart.c')
-rw-r--r-- | drivers/nfc/nfcmrvl/uart.c | 225 |
1 files changed, 225 insertions, 0 deletions
diff --git a/drivers/nfc/nfcmrvl/uart.c b/drivers/nfc/nfcmrvl/uart.c new file mode 100644 index 0000000..61442d6 --- /dev/null +++ b/drivers/nfc/nfcmrvl/uart.c @@ -0,0 +1,225 @@ +/** + * Marvell NFC-over-UART driver + * + * Copyright (C) 2015, Marvell International Ltd. + * + * This software file (the "File") is distributed by Marvell International + * Ltd. under the terms of the GNU General Public License Version 2, June 1991 + * (the "License"). You may use, redistribute and/or modify this File in + * accordance with the terms and conditions of the License, a copy of which + * is available on the worldwide web at + * http://www.gnu.org/licenses/old-licenses/gpl-2.0.txt. + * + * THE FILE IS DISTRIBUTED AS-IS, WITHOUT WARRANTY OF ANY KIND, AND THE + * IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE + * ARE EXPRESSLY DISCLAIMED. The License provides additional details about + * this warranty disclaimer. + */ + +#include <linux/module.h> +#include <linux/delay.h> +#include <linux/of_gpio.h> +#include <net/nfc/nci.h> +#include <net/nfc/nci_core.h> +#include "nfcmrvl.h" + +static unsigned int hci_muxed; +static unsigned int flow_control; +static unsigned int break_control; +static unsigned int reset_n_io; + +/* +** NFCMRVL NCI OPS +*/ + +static int nfcmrvl_uart_nci_open(struct nfcmrvl_private *priv) +{ + return 0; +} + +static int nfcmrvl_uart_nci_close(struct nfcmrvl_private *priv) +{ + return 0; +} + +static int nfcmrvl_uart_nci_send(struct nfcmrvl_private *priv, + struct sk_buff *skb) +{ + struct nci_uart *nu = priv->drv_data; + + return nu->ops.send(nu, skb); +} + +static struct nfcmrvl_if_ops uart_ops = { + .nci_open = nfcmrvl_uart_nci_open, + .nci_close = nfcmrvl_uart_nci_close, + .nci_send = nfcmrvl_uart_nci_send, +}; + +#ifdef CONFIG_OF + +static int nfcmrvl_uart_parse_dt(struct device_node *node, + struct nfcmrvl_platform_data *pdata) +{ + struct device_node *matched_node; + int ret; + + matched_node = of_find_compatible_node(node, NULL, "mrvl,nfc-uart"); + if (!matched_node) + return -ENODEV; + + ret = nfcmrvl_parse_dt(matched_node, pdata); + if (ret < 0) { + pr_err("Failed to get generic entries\n"); + return ret; + } + + if (of_find_property(matched_node, "flow-control", NULL)) + pdata->flow_control = 1; + else + pdata->flow_control = 0; + + if (of_find_property(matched_node, "break-control", NULL)) + pdata->break_control = 1; + else + pdata->break_control = 0; + + return 0; +} + +#else + +static int nfcmrvl_uart_parse_dt(struct device_node *node, + struct nfcmrvl_platform_data *pdata) +{ + return -ENODEV; +} + +#endif + +/* +** NCI UART OPS +*/ + +static int nfcmrvl_nci_uart_open(struct nci_uart *nu) +{ + struct nfcmrvl_private *priv; + struct nfcmrvl_platform_data *pdata = NULL; + struct nfcmrvl_platform_data config; + + /* + * Platform data cannot be used here since usually it is already used + * by low level serial driver. We can try to retrieve serial device + * and check if DT entries were added. + */ + + if (nu->tty->dev->parent && nu->tty->dev->parent->of_node) + if (nfcmrvl_uart_parse_dt(nu->tty->dev->parent->of_node, + &config) == 0) + pdata = &config; + + if (!pdata) { + pr_info("No platform data / DT -> fallback to module params\n"); + config.hci_muxed = hci_muxed; + config.reset_n_io = reset_n_io; + config.flow_control = flow_control; + config.break_control = break_control; + pdata = &config; + } + + priv = nfcmrvl_nci_register_dev(nu, &uart_ops, nu->tty->dev, pdata); + if (IS_ERR(priv)) + return PTR_ERR(priv); + + priv->phy = NFCMRVL_PHY_UART; + + nu->drv_data = priv; + nu->ndev = priv->ndev; + + /* Set BREAK */ + if (priv->config.break_control && nu->tty->ops->break_ctl) + nu->tty->ops->break_ctl(nu->tty, -1); + + return 0; +} + +static void nfcmrvl_nci_uart_close(struct nci_uart *nu) +{ + nfcmrvl_nci_unregister_dev((struct nfcmrvl_private *)nu->drv_data); +} + +static int nfcmrvl_nci_uart_recv(struct nci_uart *nu, struct sk_buff *skb) +{ + return nfcmrvl_nci_recv_frame((struct nfcmrvl_private *)nu->drv_data, + skb); +} + +static void nfcmrvl_nci_uart_tx_start(struct nci_uart *nu) +{ + struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data; + + /* Remove BREAK to wake up the NFCC */ + if (priv->config.break_control && nu->tty->ops->break_ctl) { + nu->tty->ops->break_ctl(nu->tty, 0); + usleep_range(3000, 5000); + } +} + +static void nfcmrvl_nci_uart_tx_done(struct nci_uart *nu) +{ + struct nfcmrvl_private *priv = (struct nfcmrvl_private *)nu->drv_data; + + /* + ** To ensure that if the NFCC goes in DEEP SLEEP sate we can wake him + ** up. we set BREAK. Once we will be ready to send again we will remove + ** it. + */ + if (priv->config.break_control && nu->tty->ops->break_ctl) + nu->tty->ops->break_ctl(nu->tty, -1); +} + +static struct nci_uart nfcmrvl_nci_uart = { + .owner = THIS_MODULE, + .name = "nfcmrvl_uart", + .driver = NCI_UART_DRIVER_MARVELL, + .ops = { + .open = nfcmrvl_nci_uart_open, + .close = nfcmrvl_nci_uart_close, + .recv = nfcmrvl_nci_uart_recv, + .tx_start = nfcmrvl_nci_uart_tx_start, + .tx_done = nfcmrvl_nci_uart_tx_done, + } +}; + +/* +** Module init +*/ + +static int nfcmrvl_uart_init_module(void) +{ + return nci_uart_register(&nfcmrvl_nci_uart); +} + +static void nfcmrvl_uart_exit_module(void) +{ + nci_uart_unregister(&nfcmrvl_nci_uart); +} + +module_init(nfcmrvl_uart_init_module); +module_exit(nfcmrvl_uart_exit_module); + +MODULE_AUTHOR("Marvell International Ltd."); +MODULE_DESCRIPTION("Marvell NFC-over-UART"); +MODULE_LICENSE("GPL v2"); + +module_param(flow_control, uint, 0); +MODULE_PARM_DESC(flow_control, "Tell if UART needs flow control at init."); + +module_param(break_control, uint, 0); +MODULE_PARM_DESC(break_control, "Tell if UART driver must drive break signal."); + +module_param(hci_muxed, uint, 0); +MODULE_PARM_DESC(hci_muxed, "Tell if transport is muxed in HCI one."); + +module_param(reset_n_io, uint, 0); +MODULE_PARM_DESC(reset_n_io, "GPIO that is wired to RESET_N signal."); |