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path: root/drivers/nfc/nfcmrvl/uart.c
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Diffstat (limited to 'drivers/nfc/nfcmrvl/uart.c')
-rw-r--r--drivers/nfc/nfcmrvl/uart.c225
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 000000000000..61442d6528a6
--- /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.");