// SPDX-License-Identifier: GPL-2.0+ /* * UART Link Layer for S3FWRN82 NCI based Driver * * Copyright (C) 2015 Samsung Electronics * Robert Baldyga <r.baldyga@samsung.com> * Copyright (C) 2020 Samsung Electronics * Bongsu Jeon <bongsu.jeon@samsung.com> */ #include <linux/device.h> #include <linux/kernel.h> #include <linux/module.h> #include <linux/nfc.h> #include <linux/netdevice.h> #include <linux/of.h> #include <linux/serdev.h> #include <linux/gpio.h> #include <linux/of_gpio.h> #include "phy_common.h" #define S3FWRN82_NCI_HEADER 3 #define S3FWRN82_NCI_IDX 2 #define NCI_SKB_BUFF_LEN 258 struct s3fwrn82_uart_phy { struct phy_common common; struct serdev_device *ser_dev; struct sk_buff *recv_skb; }; static int s3fwrn82_uart_write(void *phy_id, struct sk_buff *out) { struct s3fwrn82_uart_phy *phy = phy_id; int err; err = serdev_device_write(phy->ser_dev, out->data, out->len, MAX_SCHEDULE_TIMEOUT); if (err < 0) return err; return 0; } static const struct s3fwrn5_phy_ops uart_phy_ops = { .set_wake = s3fwrn5_phy_set_wake, .set_mode = s3fwrn5_phy_set_mode, .get_mode = s3fwrn5_phy_get_mode, .write = s3fwrn82_uart_write, }; static int s3fwrn82_uart_read(struct serdev_device *serdev, const unsigned char *data, size_t count) { struct s3fwrn82_uart_phy *phy = serdev_device_get_drvdata(serdev); size_t i; for (i = 0; i < count; i++) { skb_put_u8(phy->recv_skb, *data++); if (phy->recv_skb->len < S3FWRN82_NCI_HEADER) continue; if ((phy->recv_skb->len - S3FWRN82_NCI_HEADER) < phy->recv_skb->data[S3FWRN82_NCI_IDX]) continue; s3fwrn5_recv_frame(phy->common.ndev, phy->recv_skb, phy->common.mode); phy->recv_skb = alloc_skb(NCI_SKB_BUFF_LEN, GFP_KERNEL); if (!phy->recv_skb) return 0; } return i; } static const struct serdev_device_ops s3fwrn82_serdev_ops = { .receive_buf = s3fwrn82_uart_read, .write_wakeup = serdev_device_write_wakeup, }; static const struct of_device_id s3fwrn82_uart_of_match[] = { { .compatible = "samsung,s3fwrn82", }, {}, }; MODULE_DEVICE_TABLE(of, s3fwrn82_uart_of_match); static int s3fwrn82_uart_parse_dt(struct serdev_device *serdev) { struct s3fwrn82_uart_phy *phy = serdev_device_get_drvdata(serdev); struct device_node *np = serdev->dev.of_node; if (!np) return -ENODEV; phy->common.gpio_en = of_get_named_gpio(np, "en-gpios", 0); if (!gpio_is_valid(phy->common.gpio_en)) return -ENODEV; phy->common.gpio_fw_wake = of_get_named_gpio(np, "wake-gpios", 0); if (!gpio_is_valid(phy->common.gpio_fw_wake)) return -ENODEV; return 0; } static int s3fwrn82_uart_probe(struct serdev_device *serdev) { struct s3fwrn82_uart_phy *phy; int ret = -ENOMEM; phy = devm_kzalloc(&serdev->dev, sizeof(*phy), GFP_KERNEL); if (!phy) goto err_exit; phy->recv_skb = alloc_skb(NCI_SKB_BUFF_LEN, GFP_KERNEL); if (!phy->recv_skb) goto err_exit; mutex_init(&phy->common.mutex); phy->common.mode = S3FWRN5_MODE_COLD; phy->ser_dev = serdev; serdev_device_set_drvdata(serdev, phy); serdev_device_set_client_ops(serdev, &s3fwrn82_serdev_ops); ret = serdev_device_open(serdev); if (ret) { dev_err(&serdev->dev, "Unable to open device\n"); goto err_skb; } ret = serdev_device_set_baudrate(serdev, 115200); if (ret != 115200) { ret = -EINVAL; goto err_serdev; } serdev_device_set_flow_control(serdev, false); ret = s3fwrn82_uart_parse_dt(serdev); if (ret < 0) goto err_serdev; ret = devm_gpio_request_one(&phy->ser_dev->dev, phy->common.gpio_en, GPIOF_OUT_INIT_HIGH, "s3fwrn82_en"); if (ret < 0) goto err_serdev; ret = devm_gpio_request_one(&phy->ser_dev->dev, phy->common.gpio_fw_wake, GPIOF_OUT_INIT_LOW, "s3fwrn82_fw_wake"); if (ret < 0) goto err_serdev; ret = s3fwrn5_probe(&phy->common.ndev, phy, &phy->ser_dev->dev, &uart_phy_ops); if (ret < 0) goto err_serdev; return ret; err_serdev: serdev_device_close(serdev); err_skb: kfree_skb(phy->recv_skb); err_exit: return ret; } static void s3fwrn82_uart_remove(struct serdev_device *serdev) { struct s3fwrn82_uart_phy *phy = serdev_device_get_drvdata(serdev); s3fwrn5_remove(phy->common.ndev); serdev_device_close(serdev); kfree_skb(phy->recv_skb); } static struct serdev_device_driver s3fwrn82_uart_driver = { .probe = s3fwrn82_uart_probe, .remove = s3fwrn82_uart_remove, .driver = { .name = "s3fwrn82_uart", .of_match_table = s3fwrn82_uart_of_match, }, }; module_serdev_device_driver(s3fwrn82_uart_driver); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("UART driver for Samsung NFC"); MODULE_AUTHOR("Bongsu Jeon <bongsu.jeon@samsung.com>");