768 lines
18 KiB
C
768 lines
18 KiB
C
/*
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* UART driver for the Greybus "generic" UART module.
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*
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* Copyright 2014 Google Inc.
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* Copyright 2014 Linaro Ltd.
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*
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* Released under the GPLv2 only.
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*
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* Heavily based on drivers/usb/class/cdc-acm.c and
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* drivers/usb/serial/usb-serial.c.
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*/
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#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
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#include <linux/kernel.h>
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#include <linux/errno.h>
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#include <linux/module.h>
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#include <linux/sched.h>
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#include <linux/wait.h>
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#include <linux/slab.h>
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#include <linux/uaccess.h>
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#include <linux/mutex.h>
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#include <linux/tty.h>
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#include <linux/serial.h>
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#include <linux/tty_driver.h>
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#include <linux/tty_flip.h>
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#include <linux/serial.h>
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#include <linux/idr.h>
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#include <linux/fs.h>
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#include <linux/kdev_t.h>
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#include "greybus.h"
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#define GB_NUM_MINORS 16 /* 16 is is more than enough */
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#define GB_NAME "ttyGB"
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struct gb_tty_line_coding {
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__le32 rate;
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__u8 format;
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__u8 parity;
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__u8 data_bits;
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};
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struct gb_tty {
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struct tty_port port;
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void *buffer;
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u32 buffer_payload_max;
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struct gb_connection *connection;
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u16 cport_id;
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unsigned int minor;
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unsigned char clocal;
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bool disconnected;
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spinlock_t read_lock;
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spinlock_t write_lock;
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struct async_icount iocount;
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struct async_icount oldcount;
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wait_queue_head_t wioctl;
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struct mutex mutex;
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u8 ctrlin; /* input control lines */
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u8 ctrlout; /* output control lines */
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struct gb_tty_line_coding line_coding;
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};
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static struct tty_driver *gb_tty_driver;
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static DEFINE_IDR(tty_minors);
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static DEFINE_MUTEX(table_lock);
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static atomic_t reference_count = ATOMIC_INIT(0);
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static int gb_uart_receive_data(struct gb_tty *gb_tty,
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struct gb_connection *connection,
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struct gb_uart_recv_data_request *receive_data)
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{
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struct tty_port *port = &gb_tty->port;
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u16 recv_data_size;
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int count;
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unsigned long tty_flags = TTY_NORMAL;
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count = gb_tty->buffer_payload_max - sizeof(*receive_data);
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recv_data_size = le16_to_cpu(receive_data->size);
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if (!recv_data_size || recv_data_size > count)
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return -EINVAL;
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if (receive_data->flags) {
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if (receive_data->flags & GB_UART_RECV_FLAG_BREAK)
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tty_flags = TTY_BREAK;
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else if (receive_data->flags & GB_UART_RECV_FLAG_PARITY)
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tty_flags = TTY_PARITY;
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else if (receive_data->flags & GB_UART_RECV_FLAG_FRAMING)
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tty_flags = TTY_FRAME;
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/* overrun is special, not associated with a char */
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if (receive_data->flags & GB_UART_RECV_FLAG_OVERRUN)
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tty_insert_flip_char(port, 0, TTY_OVERRUN);
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}
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count = tty_insert_flip_string_fixed_flag(port, receive_data->data,
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tty_flags, recv_data_size);
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if (count != recv_data_size) {
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dev_err(&connection->bundle->dev,
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"UART: RX 0x%08x bytes only wrote 0x%08x\n",
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recv_data_size, count);
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}
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if (count)
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tty_flip_buffer_push(port);
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return 0;
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}
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static int gb_uart_request_recv(u8 type, struct gb_operation *op)
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{
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struct gb_connection *connection = op->connection;
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struct gb_tty *gb_tty = connection->private;
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struct gb_message *request = op->request;
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struct gb_uart_serial_state_request *serial_state;
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int ret = 0;
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switch (type) {
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case GB_UART_TYPE_RECEIVE_DATA:
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ret = gb_uart_receive_data(gb_tty, connection,
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request->payload);
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break;
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case GB_UART_TYPE_SERIAL_STATE:
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serial_state = request->payload;
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gb_tty->ctrlin = serial_state->control;
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break;
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default:
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dev_err(&connection->bundle->dev,
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"unsupported unsolicited request: 0x%02x\n", type);
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ret = -EINVAL;
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}
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return ret;
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}
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static int send_data(struct gb_tty *tty, u16 size, const u8 *data)
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{
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struct gb_uart_send_data_request *request;
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int ret;
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if (!data || !size)
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return 0;
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if (size > tty->buffer_payload_max)
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size = tty->buffer_payload_max;
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request = tty->buffer;
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request->size = cpu_to_le16(size);
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memcpy(&request->data[0], data, size);
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ret = gb_operation_sync(tty->connection, GB_UART_TYPE_SEND_DATA,
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request, sizeof(*request) + size, NULL, 0);
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if (ret)
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return ret;
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else
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return size;
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}
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static int send_line_coding(struct gb_tty *tty)
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{
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struct gb_uart_set_line_coding_request request;
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memcpy(&request, &tty->line_coding,
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sizeof(tty->line_coding));
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return gb_operation_sync(tty->connection, GB_UART_TYPE_SET_LINE_CODING,
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&request, sizeof(request), NULL, 0);
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}
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static int send_control(struct gb_tty *gb_tty, u8 control)
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{
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struct gb_uart_set_control_line_state_request request;
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request.control = control;
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return gb_operation_sync(gb_tty->connection,
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GB_UART_TYPE_SET_CONTROL_LINE_STATE,
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&request, sizeof(request), NULL, 0);
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}
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static int send_break(struct gb_tty *gb_tty, u8 state)
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{
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struct gb_uart_set_break_request request;
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if ((state != 0) && (state != 1)) {
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dev_err(&gb_tty->connection->bundle->dev,
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"invalid break state of %d\n", state);
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return -EINVAL;
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}
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request.state = state;
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return gb_operation_sync(gb_tty->connection, GB_UART_TYPE_SEND_BREAK,
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&request, sizeof(request), NULL, 0);
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}
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static struct gb_tty *get_gb_by_minor(unsigned minor)
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{
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struct gb_tty *gb_tty;
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mutex_lock(&table_lock);
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gb_tty = idr_find(&tty_minors, minor);
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if (gb_tty) {
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mutex_lock(&gb_tty->mutex);
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if (gb_tty->disconnected) {
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mutex_unlock(&gb_tty->mutex);
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gb_tty = NULL;
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} else {
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tty_port_get(&gb_tty->port);
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mutex_unlock(&gb_tty->mutex);
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}
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}
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mutex_unlock(&table_lock);
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return gb_tty;
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}
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static int alloc_minor(struct gb_tty *gb_tty)
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{
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int minor;
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mutex_lock(&table_lock);
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minor = idr_alloc(&tty_minors, gb_tty, 0, GB_NUM_MINORS, GFP_KERNEL);
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mutex_unlock(&table_lock);
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if (minor >= 0)
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gb_tty->minor = minor;
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return minor;
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}
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static void release_minor(struct gb_tty *gb_tty)
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{
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int minor = gb_tty->minor;
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gb_tty->minor = 0; /* Maybe should use an invalid value instead */
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mutex_lock(&table_lock);
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idr_remove(&tty_minors, minor);
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mutex_unlock(&table_lock);
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}
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static int gb_tty_install(struct tty_driver *driver, struct tty_struct *tty)
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{
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struct gb_tty *gb_tty;
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int retval;
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gb_tty = get_gb_by_minor(tty->index);
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if (!gb_tty)
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return -ENODEV;
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retval = tty_standard_install(driver, tty);
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if (retval)
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goto error;
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tty->driver_data = gb_tty;
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return 0;
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error:
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tty_port_put(&gb_tty->port);
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return retval;
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}
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static int gb_tty_open(struct tty_struct *tty, struct file *file)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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return tty_port_open(&gb_tty->port, tty, file);
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}
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static void gb_tty_close(struct tty_struct *tty, struct file *file)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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tty_port_close(&gb_tty->port, tty, file);
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}
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static void gb_tty_cleanup(struct tty_struct *tty)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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tty_port_put(&gb_tty->port);
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}
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static void gb_tty_hangup(struct tty_struct *tty)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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tty_port_hangup(&gb_tty->port);
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}
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static int gb_tty_write(struct tty_struct *tty, const unsigned char *buf,
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int count)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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return send_data(gb_tty, count, buf);
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}
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static int gb_tty_write_room(struct tty_struct *tty)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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return gb_tty->buffer_payload_max;
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}
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static int gb_tty_chars_in_buffer(struct tty_struct *tty)
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{
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return 0;
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}
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static int gb_tty_break_ctl(struct tty_struct *tty, int state)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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return send_break(gb_tty, state ? 1 : 0);
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}
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static void gb_tty_set_termios(struct tty_struct *tty,
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struct ktermios *termios_old)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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struct ktermios *termios = &tty->termios;
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struct gb_tty_line_coding newline;
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u8 newctrl = gb_tty->ctrlout;
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newline.rate = cpu_to_le32(tty_get_baud_rate(tty));
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newline.format = termios->c_cflag & CSTOPB ?
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GB_SERIAL_2_STOP_BITS : GB_SERIAL_1_STOP_BITS;
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newline.parity = termios->c_cflag & PARENB ?
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(termios->c_cflag & PARODD ? 1 : 2) +
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(termios->c_cflag & CMSPAR ? 2 : 0) : 0;
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switch (termios->c_cflag & CSIZE) {
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case CS5:
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newline.data_bits = 5;
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break;
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case CS6:
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newline.data_bits = 6;
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break;
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case CS7:
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newline.data_bits = 7;
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break;
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case CS8:
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default:
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newline.data_bits = 8;
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break;
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}
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/* FIXME: needs to clear unsupported bits in the termios */
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gb_tty->clocal = ((termios->c_cflag & CLOCAL) != 0);
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if (C_BAUD(tty) == B0) {
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newline.rate = gb_tty->line_coding.rate;
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newctrl &= GB_UART_CTRL_DTR;
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} else if (termios_old && (termios_old->c_cflag & CBAUD) == B0) {
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newctrl |= GB_UART_CTRL_DTR;
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}
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if (newctrl != gb_tty->ctrlout) {
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gb_tty->ctrlout = newctrl;
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send_control(gb_tty, newctrl);
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}
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if (memcpy(&gb_tty->line_coding, &newline, sizeof(newline))) {
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memcpy(&gb_tty->line_coding, &newline, sizeof(newline));
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send_line_coding(gb_tty);
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}
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}
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static int gb_tty_tiocmget(struct tty_struct *tty)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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return (gb_tty->ctrlout & GB_UART_CTRL_DTR ? TIOCM_DTR : 0) |
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(gb_tty->ctrlout & GB_UART_CTRL_RTS ? TIOCM_RTS : 0) |
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(gb_tty->ctrlin & GB_UART_CTRL_DSR ? TIOCM_DSR : 0) |
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(gb_tty->ctrlin & GB_UART_CTRL_RI ? TIOCM_RI : 0) |
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(gb_tty->ctrlin & GB_UART_CTRL_DCD ? TIOCM_CD : 0) |
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TIOCM_CTS;
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}
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static int gb_tty_tiocmset(struct tty_struct *tty, unsigned int set,
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unsigned int clear)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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u8 newctrl = gb_tty->ctrlout;
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set = (set & TIOCM_DTR ? GB_UART_CTRL_DTR : 0) |
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(set & TIOCM_RTS ? GB_UART_CTRL_RTS : 0);
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clear = (clear & TIOCM_DTR ? GB_UART_CTRL_DTR : 0) |
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(clear & TIOCM_RTS ? GB_UART_CTRL_RTS : 0);
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newctrl = (newctrl & ~clear) | set;
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if (gb_tty->ctrlout == newctrl)
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return 0;
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gb_tty->ctrlout = newctrl;
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return send_control(gb_tty, newctrl);
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}
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static void gb_tty_throttle(struct tty_struct *tty)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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unsigned char stop_char;
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int retval;
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if (I_IXOFF(tty)) {
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stop_char = STOP_CHAR(tty);
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retval = gb_tty_write(tty, &stop_char, 1);
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if (retval <= 0)
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return;
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}
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if (tty->termios.c_cflag & CRTSCTS) {
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gb_tty->ctrlout &= ~GB_UART_CTRL_RTS;
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retval = send_control(gb_tty, gb_tty->ctrlout);
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}
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}
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static void gb_tty_unthrottle(struct tty_struct *tty)
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{
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struct gb_tty *gb_tty = tty->driver_data;
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unsigned char start_char;
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int retval;
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if (I_IXOFF(tty)) {
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start_char = START_CHAR(tty);
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retval = gb_tty_write(tty, &start_char, 1);
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if (retval <= 0)
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return;
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}
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if (tty->termios.c_cflag & CRTSCTS) {
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gb_tty->ctrlout |= GB_UART_CTRL_RTS;
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retval = send_control(gb_tty, gb_tty->ctrlout);
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}
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}
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static int get_serial_info(struct gb_tty *gb_tty,
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struct serial_struct __user *info)
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{
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struct serial_struct tmp;
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if (!info)
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return -EINVAL;
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memset(&tmp, 0, sizeof(tmp));
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tmp.flags = ASYNC_LOW_LATENCY | ASYNC_SKIP_TEST;
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tmp.type = PORT_16550A;
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tmp.line = gb_tty->minor;
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tmp.xmit_fifo_size = 16;
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tmp.baud_base = 9600;
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tmp.close_delay = gb_tty->port.close_delay / 10;
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tmp.closing_wait = gb_tty->port.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
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ASYNC_CLOSING_WAIT_NONE : gb_tty->port.closing_wait / 10;
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if (copy_to_user(info, &tmp, sizeof(tmp)))
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return -EFAULT;
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return 0;
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}
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static int set_serial_info(struct gb_tty *gb_tty,
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struct serial_struct __user *newinfo)
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{
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struct serial_struct new_serial;
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unsigned int closing_wait;
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unsigned int close_delay;
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int retval = 0;
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if (copy_from_user(&new_serial, newinfo, sizeof(new_serial)))
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return -EFAULT;
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close_delay = new_serial.close_delay * 10;
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closing_wait = new_serial.closing_wait == ASYNC_CLOSING_WAIT_NONE ?
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ASYNC_CLOSING_WAIT_NONE : new_serial.closing_wait * 10;
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mutex_lock(&gb_tty->port.mutex);
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if (!capable(CAP_SYS_ADMIN)) {
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if ((close_delay != gb_tty->port.close_delay) ||
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(closing_wait != gb_tty->port.closing_wait))
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retval = -EPERM;
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else
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retval = -EOPNOTSUPP;
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} else {
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gb_tty->port.close_delay = close_delay;
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gb_tty->port.closing_wait = closing_wait;
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}
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mutex_unlock(&gb_tty->port.mutex);
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return retval;
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}
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static int wait_serial_change(struct gb_tty *gb_tty, unsigned long arg)
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{
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int retval = 0;
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DECLARE_WAITQUEUE(wait, current);
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struct async_icount old;
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struct async_icount new;
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if (!(arg & (TIOCM_DSR | TIOCM_RI | TIOCM_CD)))
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return -EINVAL;
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do {
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spin_lock_irq(&gb_tty->read_lock);
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old = gb_tty->oldcount;
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new = gb_tty->iocount;
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gb_tty->oldcount = new;
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spin_unlock_irq(&gb_tty->read_lock);
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if ((arg & TIOCM_DSR) && (old.dsr != new.dsr))
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break;
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if ((arg & TIOCM_CD) && (old.dcd != new.dcd))
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break;
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if ((arg & TIOCM_RI) && (old.rng != new.rng))
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break;
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add_wait_queue(&gb_tty->wioctl, &wait);
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set_current_state(TASK_INTERRUPTIBLE);
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schedule();
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|
remove_wait_queue(&gb_tty->wioctl, &wait);
|
|
if (gb_tty->disconnected) {
|
|
if (arg & TIOCM_CD)
|
|
break;
|
|
retval = -ENODEV;
|
|
} else if (signal_pending(current)) {
|
|
retval = -ERESTARTSYS;
|
|
}
|
|
} while (!retval);
|
|
|
|
return retval;
|
|
}
|
|
|
|
static int get_serial_usage(struct gb_tty *gb_tty,
|
|
struct serial_icounter_struct __user *count)
|
|
{
|
|
struct serial_icounter_struct icount;
|
|
int retval = 0;
|
|
|
|
memset(&icount, 0, sizeof(icount));
|
|
icount.dsr = gb_tty->iocount.dsr;
|
|
icount.rng = gb_tty->iocount.rng;
|
|
icount.dcd = gb_tty->iocount.dcd;
|
|
icount.frame = gb_tty->iocount.frame;
|
|
icount.overrun = gb_tty->iocount.overrun;
|
|
icount.parity = gb_tty->iocount.parity;
|
|
icount.brk = gb_tty->iocount.brk;
|
|
|
|
if (copy_to_user(count, &icount, sizeof(icount)) > 0)
|
|
retval = -EFAULT;
|
|
|
|
return retval;
|
|
}
|
|
|
|
static int gb_tty_ioctl(struct tty_struct *tty, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
struct gb_tty *gb_tty = tty->driver_data;
|
|
|
|
switch (cmd) {
|
|
case TIOCGSERIAL:
|
|
return get_serial_info(gb_tty,
|
|
(struct serial_struct __user *)arg);
|
|
case TIOCSSERIAL:
|
|
return set_serial_info(gb_tty,
|
|
(struct serial_struct __user *)arg);
|
|
case TIOCMIWAIT:
|
|
return wait_serial_change(gb_tty, arg);
|
|
case TIOCGICOUNT:
|
|
return get_serial_usage(gb_tty,
|
|
(struct serial_icounter_struct __user *)arg);
|
|
}
|
|
|
|
return -ENOIOCTLCMD;
|
|
}
|
|
|
|
|
|
static const struct tty_operations gb_ops = {
|
|
.install = gb_tty_install,
|
|
.open = gb_tty_open,
|
|
.close = gb_tty_close,
|
|
.cleanup = gb_tty_cleanup,
|
|
.hangup = gb_tty_hangup,
|
|
.write = gb_tty_write,
|
|
.write_room = gb_tty_write_room,
|
|
.ioctl = gb_tty_ioctl,
|
|
.throttle = gb_tty_throttle,
|
|
.unthrottle = gb_tty_unthrottle,
|
|
.chars_in_buffer = gb_tty_chars_in_buffer,
|
|
.break_ctl = gb_tty_break_ctl,
|
|
.set_termios = gb_tty_set_termios,
|
|
.tiocmget = gb_tty_tiocmget,
|
|
.tiocmset = gb_tty_tiocmset,
|
|
};
|
|
|
|
static struct tty_port_operations null_ops = { };
|
|
|
|
static int gb_tty_init(void);
|
|
static void gb_tty_exit(void);
|
|
|
|
static int gb_uart_connection_init(struct gb_connection *connection)
|
|
{
|
|
struct gb_tty *gb_tty;
|
|
struct device *tty_dev;
|
|
int retval;
|
|
int minor;
|
|
|
|
/* First time here, initialize the tty structures */
|
|
if (atomic_inc_return(&reference_count) == 1) {
|
|
retval = gb_tty_init();
|
|
if (retval) {
|
|
atomic_dec(&reference_count);
|
|
return retval;
|
|
}
|
|
}
|
|
|
|
gb_tty = kzalloc(sizeof(*gb_tty), GFP_KERNEL);
|
|
if (!gb_tty) {
|
|
retval = -ENOMEM;
|
|
goto error_alloc;
|
|
}
|
|
|
|
gb_tty->buffer_payload_max =
|
|
gb_operation_get_payload_size_max(connection);
|
|
if (!gb_tty->buffer_payload_max) {
|
|
retval = -EINVAL;
|
|
goto error_payload;
|
|
}
|
|
|
|
gb_tty->buffer = kzalloc(gb_tty->buffer_payload_max, GFP_KERNEL);
|
|
if (!gb_tty->buffer) {
|
|
retval = -ENOMEM;
|
|
goto error_payload;
|
|
}
|
|
|
|
gb_tty->connection = connection;
|
|
connection->private = gb_tty;
|
|
|
|
minor = alloc_minor(gb_tty);
|
|
if (minor < 0) {
|
|
if (minor == -ENOSPC) {
|
|
dev_err(&connection->bundle->dev,
|
|
"no more free minor numbers\n");
|
|
retval = -ENODEV;
|
|
goto error_minor;
|
|
}
|
|
retval = minor;
|
|
goto error_minor;
|
|
}
|
|
|
|
gb_tty->minor = minor;
|
|
spin_lock_init(&gb_tty->write_lock);
|
|
spin_lock_init(&gb_tty->read_lock);
|
|
init_waitqueue_head(&gb_tty->wioctl);
|
|
mutex_init(&gb_tty->mutex);
|
|
|
|
tty_port_init(&gb_tty->port);
|
|
gb_tty->port.ops = &null_ops;
|
|
|
|
send_control(gb_tty, gb_tty->ctrlout);
|
|
|
|
/* initialize the uart to be 9600n81 */
|
|
gb_tty->line_coding.rate = cpu_to_le32(9600);
|
|
gb_tty->line_coding.format = GB_SERIAL_1_STOP_BITS;
|
|
gb_tty->line_coding.parity = GB_SERIAL_NO_PARITY;
|
|
gb_tty->line_coding.data_bits = 8;
|
|
send_line_coding(gb_tty);
|
|
|
|
tty_dev = tty_port_register_device(&gb_tty->port, gb_tty_driver, minor,
|
|
&connection->bundle->dev);
|
|
if (IS_ERR(tty_dev)) {
|
|
retval = PTR_ERR(tty_dev);
|
|
goto error;
|
|
}
|
|
|
|
return 0;
|
|
error:
|
|
tty_port_destroy(&gb_tty->port);
|
|
release_minor(gb_tty);
|
|
error_minor:
|
|
connection->private = NULL;
|
|
kfree(gb_tty->buffer);
|
|
error_payload:
|
|
kfree(gb_tty);
|
|
error_alloc:
|
|
if (atomic_dec_return(&reference_count) == 0)
|
|
gb_tty_exit();
|
|
return retval;
|
|
}
|
|
|
|
static void gb_uart_connection_exit(struct gb_connection *connection)
|
|
{
|
|
struct gb_tty *gb_tty = connection->private;
|
|
struct tty_struct *tty;
|
|
|
|
if (!gb_tty)
|
|
return;
|
|
|
|
mutex_lock(&gb_tty->mutex);
|
|
gb_tty->disconnected = true;
|
|
|
|
wake_up_all(&gb_tty->wioctl);
|
|
connection->private = NULL;
|
|
mutex_unlock(&gb_tty->mutex);
|
|
|
|
tty = tty_port_tty_get(&gb_tty->port);
|
|
if (tty) {
|
|
tty_vhangup(tty);
|
|
tty_kref_put(tty);
|
|
}
|
|
/* FIXME - stop all traffic */
|
|
|
|
tty_unregister_device(gb_tty_driver, gb_tty->minor);
|
|
|
|
/* FIXME - free transmit / receive buffers */
|
|
|
|
tty_port_put(&gb_tty->port);
|
|
tty_port_destroy(&gb_tty->port);
|
|
kfree(gb_tty->buffer);
|
|
kfree(gb_tty);
|
|
|
|
/* If last device is gone, tear down the tty structures */
|
|
if (atomic_dec_return(&reference_count) == 0)
|
|
gb_tty_exit();
|
|
}
|
|
|
|
static int gb_tty_init(void)
|
|
{
|
|
int retval = 0;
|
|
|
|
gb_tty_driver = tty_alloc_driver(GB_NUM_MINORS, 0);
|
|
if (IS_ERR(gb_tty_driver)) {
|
|
pr_err("Can not allocate tty driver\n");
|
|
retval = -ENOMEM;
|
|
goto fail_unregister_dev;
|
|
}
|
|
|
|
gb_tty_driver->driver_name = "gb";
|
|
gb_tty_driver->name = GB_NAME;
|
|
gb_tty_driver->major = 0;
|
|
gb_tty_driver->minor_start = 0;
|
|
gb_tty_driver->type = TTY_DRIVER_TYPE_SERIAL;
|
|
gb_tty_driver->subtype = SERIAL_TYPE_NORMAL;
|
|
gb_tty_driver->flags = TTY_DRIVER_REAL_RAW | TTY_DRIVER_DYNAMIC_DEV;
|
|
gb_tty_driver->init_termios = tty_std_termios;
|
|
gb_tty_driver->init_termios.c_cflag = B9600 | CS8 | CREAD | HUPCL | CLOCAL;
|
|
tty_set_operations(gb_tty_driver, &gb_ops);
|
|
|
|
retval = tty_register_driver(gb_tty_driver);
|
|
if (retval) {
|
|
pr_err("Can not register tty driver: %d\n", retval);
|
|
goto fail_put_gb_tty;
|
|
}
|
|
|
|
return 0;
|
|
|
|
fail_put_gb_tty:
|
|
put_tty_driver(gb_tty_driver);
|
|
fail_unregister_dev:
|
|
return retval;
|
|
}
|
|
|
|
static void gb_tty_exit(void)
|
|
{
|
|
tty_unregister_driver(gb_tty_driver);
|
|
put_tty_driver(gb_tty_driver);
|
|
idr_destroy(&tty_minors);
|
|
}
|
|
|
|
static struct gb_protocol uart_protocol = {
|
|
.name = "uart",
|
|
.id = GREYBUS_PROTOCOL_UART,
|
|
.major = GB_UART_VERSION_MAJOR,
|
|
.minor = GB_UART_VERSION_MINOR,
|
|
.connection_init = gb_uart_connection_init,
|
|
.connection_exit = gb_uart_connection_exit,
|
|
.request_recv = gb_uart_request_recv,
|
|
};
|
|
|
|
gb_builtin_protocol_driver(uart_protocol);
|