Return-path: Received: from mx08-00178001.pphosted.com ([91.207.212.93]:26991 "EHLO mx07-00178001.pphosted.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1751015AbdEBGE0 (ORCPT ); Tue, 2 May 2017 02:04:26 -0400 From: Shikha Singh To: , , CC: , , , , , Subject: [[linux-nfc][PATCH v1] 3/6] NFC: nfcst: Add UART LDisc Driver Date: Tue, 2 May 2017 02:03:40 -0400 Message-ID: <1493705023-8710-4-git-send-email-shikha.singh@st.com> (sfid-20170502_080431_634061_8B474715) In-Reply-To: <1493705023-8710-1-git-send-email-shikha.singh@st.com> References: <1493705023-8710-1-git-send-email-shikha.singh@st.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-wireless-owner@vger.kernel.org List-ID: Add support of ST NFC transceiver controlled over UART. This driver registers with the digital LDisc UART framework as an UART LDisc driver, and as a phy driver with the ST NFC transceiver core framework. Signed-off-by: Shikha Singh --- drivers/nfc/nfcst/Kconfig | 17 +++++ drivers/nfc/nfcst/Makefile | 3 + drivers/nfc/nfcst/uart.c | 164 +++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 184 insertions(+) create mode 100644 drivers/nfc/nfcst/uart.c diff --git a/drivers/nfc/nfcst/Kconfig b/drivers/nfc/nfcst/Kconfig index 2c71aa2..70fec4f 100644 --- a/drivers/nfc/nfcst/Kconfig +++ b/drivers/nfc/nfcst/Kconfig @@ -15,3 +15,20 @@ config NFC_ST Say Y here to compile support for ST NFC transceiver core framework into the kernel or say M to compile it as module. + +config NFC_ST_UART + tristate "ST NFC-over-UART driver" + depends on NFC_DIGITAL && NFC_DIGITAL_UART + select NFC_ST + help + ST NFC-over-UART driver. + + This driver is an UART LDisc driver that helps + ST NFC transceiver core framework communicate with + the transceiver device over the UART interface. + The driver registers as a phy driver with the core, + and as an LDisc driver with the digital UART LDisc + framework. + + Say Y here to compile support for ST NFC-over-UART driver + into the kernel or say M to compile it as module. diff --git a/drivers/nfc/nfcst/Makefile b/drivers/nfc/nfcst/Makefile index d46acc5..a90055a 100644 --- a/drivers/nfc/nfcst/Makefile +++ b/drivers/nfc/nfcst/Makefile @@ -4,3 +4,6 @@ nfcst-y += core.o obj-$(CONFIG_NFC_ST) += nfcst.o + +nfcst_uart-y += uart.o +obj-$(CONFIG_NFC_ST_UART) += nfcst_uart.o diff --git a/drivers/nfc/nfcst/uart.c b/drivers/nfc/nfcst/uart.c new file mode 100644 index 0000000..953281d --- /dev/null +++ b/drivers/nfc/nfcst/uart.c @@ -0,0 +1,164 @@ +/* + * -------------------------------------------------------------------- + * LDisc UART Driver for ST NFC Transceiver + * -------------------------------------------------------------------- + * Copyright (C) 2016 STMicroelectronics Pvt. Ltd. All rights reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms and conditions of the GNU General Public License, + * version 2, as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see . + */ + +#include +#include +#include +#include "stnfcdev.h" + +#define DEVICE_DEFAULT_BAUD 57600 + +static unsigned int baud = DEVICE_DEFAULT_BAUD; + +static int nfcst_uart_digital_send(void *phy_ctx, struct sk_buff *skb) +{ + struct digital_uart *du = (struct digital_uart *)phy_ctx; + + return du->ops.send(du, skb); +} + +static struct nfcst_if_ops uart_ops = { + .phy_send = nfcst_uart_digital_send, +}; + +static int nfcst_uart_parse_dt(struct device_node *node, + struct nfcst_pltf_data *pdata) +{ + struct device_node *matched_node; + const void *ptr; + + matched_node = of_find_compatible_node(node, NULL, "st,nfc-uart"); + if (!matched_node) + return -ENODEV; + + ptr = of_get_property(matched_node, "st,baudrate", NULL); + if (!ptr) + return -ENODEV; + + pdata->baudrate = be32_to_cpup(ptr); + + return 0; +} + +/* + * DIGITAL UART OPS + */ +static int nfcst_digital_uart_open(struct digital_uart *du) +{ + void *priv; + int err; + struct nfcst_pltf_data config; + struct nfcst_pltf_data *pdata = NULL; + + if (du->tty->dev->parent && du->tty->dev->parent->of_node) { + err = nfcst_uart_parse_dt(du->tty->dev->parent->of_node, + &config); + if (err) + dev_err(du->tty->dev, "No st nfc uart platform data found in DT\n"); + else + pdata = &config; + } + + if (!pdata) { + dev_info(du->tty->dev, "No platform data / DT -> fallback to module params\n"); + config.baudrate = baud; + pdata = &config; + } + priv = nfcst_register_phy(PHY_UART, (void *)du, &uart_ops, + du->tty->dev, pdata); + if (IS_ERR(priv)) + return PTR_ERR(priv); + + du->drv_data = priv; + + /* set the default configuration */ + digital_uart_set_config(du, + DEVICE_DEFAULT_BAUD, + 0, + DIGITAL_UART_STOP_BIT_2); + + return 0; +} + +static void nfcst_digital_uart_close(struct digital_uart *du) +{ + nfcst_unregister_phy(du->drv_data); +} + +static int nfcst_digital_uart_recv(struct digital_uart *du, struct sk_buff *skb) +{ + return nfcst_recv_frame(du->drv_data, skb); +} + +static int nfcst_digital_uart_recv_hdr_len(struct digital_uart *du, + const u8 *data, + int count) +{ + return nfcst_recv_hdr_len(du->drv_data, data, count); +} + +static int nfcst_digital_uart_fr_len(struct digital_uart *du, + const u8 *data, + int count) +{ + return nfcst_recv_fr_len(du->drv_data, data, count); +} + +static int nfcst_digital_uart_max_fr_sz(struct digital_uart *du) +{ + return nfcst_recv_max_fr_sz(du->drv_data); +} + +static struct digital_uart nfcst_uart = { + .owner = THIS_MODULE, + .name = "nfcst_uart", + .driver = DIGITAL_UART_DRIVER_ST, + .ops = { + .open = nfcst_digital_uart_open, + .close = nfcst_digital_uart_close, + .recv = nfcst_digital_uart_recv, + .recv_fr_hdr_sz = nfcst_digital_uart_recv_hdr_len, + .recv_pl_sz = nfcst_digital_uart_fr_len, + .recv_fr_max_sz = nfcst_digital_uart_max_fr_sz, + } +}; + +/* + * Module init + */ +static int nfcst_uart_init_module(void) +{ + return digital_uart_register(&nfcst_uart); +} + +static void nfcst_uart_exit_module(void) +{ + digital_uart_unregister(&nfcst_uart); +} + +module_init(nfcst_uart_init_module); +module_exit(nfcst_uart_exit_module); + +MODULE_AUTHOR("Sudeep Biswas "); +MODULE_AUTHOR("Shikha Singh "); +MODULE_DESCRIPTION("ST NFC-over-UART"); +MODULE_LICENSE("GPL v2"); + +module_param(baud, uint, 0000); +MODULE_PARM_DESC(baud, "Tell the UART baudrate for communication"); -- 1.8.2.1