diff options
Diffstat (limited to 'drivers/nfc/s3fwrn5/uart.c')
| -rw-r--r-- | drivers/nfc/s3fwrn5/uart.c | 196 |
1 files changed, 196 insertions, 0 deletions
diff --git a/drivers/nfc/s3fwrn5/uart.c b/drivers/nfc/s3fwrn5/uart.c new file mode 100644 index 000000000000..82ea35d748a5 --- /dev/null +++ b/drivers/nfc/s3fwrn5/uart.c @@ -0,0 +1,196 @@ +// 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>"); |