[PATCH v2 1/2] usb: serial: add support for CH348

From: Corentin Labbe
Date: Fri Oct 21 2022 - 09:38:19 EST


The CH348 is an USB octo port serial adapter.
This patch adds support for it.

Signed-off-by: Corentin Labbe <clabbe@xxxxxxxxxxxx>
---
drivers/usb/serial/Kconfig | 9 +
drivers/usb/serial/Makefile | 1 +
drivers/usb/serial/ch348.c | 738 ++++++++++++++++++++++++++++++++++++
3 files changed, 748 insertions(+)
create mode 100644 drivers/usb/serial/ch348.c

diff --git a/drivers/usb/serial/Kconfig b/drivers/usb/serial/Kconfig
index ef8d1c73c754..1e1842656b54 100644
--- a/drivers/usb/serial/Kconfig
+++ b/drivers/usb/serial/Kconfig
@@ -112,6 +112,15 @@ config USB_SERIAL_CH341
To compile this driver as a module, choose M here: the
module will be called ch341.

+config USB_SERIAL_CH348
+ tristate "USB Winchiphead CH348 Octo Port Serial Driver"
+ help
+ Say Y here if you want to use a Winchiphead CH348 octo port
+ USB to serial adapter.
+
+ To compile this driver as a module, choose M here: the
+ module will be called ch348.
+
config USB_SERIAL_WHITEHEAT
tristate "USB ConnectTech WhiteHEAT Serial Driver"
select USB_EZUSB_FX2
diff --git a/drivers/usb/serial/Makefile b/drivers/usb/serial/Makefile
index c7bb1a88173e..d16ff59fde68 100644
--- a/drivers/usb/serial/Makefile
+++ b/drivers/usb/serial/Makefile
@@ -15,6 +15,7 @@ obj-$(CONFIG_USB_SERIAL_AIRCABLE) += aircable.o
obj-$(CONFIG_USB_SERIAL_ARK3116) += ark3116.o
obj-$(CONFIG_USB_SERIAL_BELKIN) += belkin_sa.o
obj-$(CONFIG_USB_SERIAL_CH341) += ch341.o
+obj-$(CONFIG_USB_SERIAL_CH348) += ch348.o
obj-$(CONFIG_USB_SERIAL_CP210X) += cp210x.o
obj-$(CONFIG_USB_SERIAL_CYBERJACK) += cyberjack.o
obj-$(CONFIG_USB_SERIAL_CYPRESS_M8) += cypress_m8.o
diff --git a/drivers/usb/serial/ch348.c b/drivers/usb/serial/ch348.c
new file mode 100644
index 000000000000..f0f9c1aaf271
--- /dev/null
+++ b/drivers/usb/serial/ch348.c
@@ -0,0 +1,738 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * USB serial driver for USB to Octal UARTs chip ch348.
+ *
+ * Copyright (C) 2022 Corentin Labbe <clabbe@xxxxxxxxxxxx>
+ * With the help of Neil Armstrong <neil.armstrong@xxxxxxxxxx>
+ */
+
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/serial.h>
+#include <linux/slab.h>
+#include <linux/tty.h>
+#include <linux/tty_driver.h>
+#include <linux/tty_flip.h>
+#include <linux/usb.h>
+#include <linux/usb/serial.h>
+
+#define DEFAULT_BAUD_RATE 9600
+#define DEFAULT_TIMEOUT 2000
+
+#define CH348_CTO_D 0x01
+#define CH348_CTO_R 0x02
+
+#define CH348_CTI_C 0x10
+#define CH348_CTI_DSR 0x20
+#define CH348_CTI_R 0x40
+#define CH348_CTI_DCD 0x80
+
+#define CH348_LO 0x02
+#define CH348_LP 0x04
+#define CH348_LF 0x08
+#define CH348_LB 0x10
+
+#define CMD_W_R 0xC0
+#define CMD_W_BR 0x80
+
+#define CMD_WB_E 0x90
+#define CMD_RB_E 0xC0
+
+#define M_NOR 0x00
+#define M_HF 0x03
+
+#define R_MOD 0x97
+#define R_IO_D 0x98
+#define R_IO_O 0x99
+#define R_IO_I 0x9b
+#define R_TM_O 0x9c
+#define R_INIT 0xa1
+
+#define R_C1 0x01
+#define R_C2 0x02
+#define R_C4 0x04
+#define R_C5 0x06
+
+#define R_II_B1 0x06
+#define R_II_B2 0x02
+#define R_II_B3 0x00
+
+struct ch348_rxbuf {
+ u8 port;
+ u8 length;
+ u8 data[];
+} __packed;
+
+#define CH348_RX_PORT_CHUNK_LENGTH 32
+#define CH348_RX_PORT_MAX_LENGTH 30
+
+struct ch348_txbuf {
+ u8 port;
+ __le16 length;
+ u8 data[];
+} __packed;
+
+struct ch348_initbuf {
+ u8 cmd;
+ u8 reg;
+ u8 port;
+ __be32 dwDTERate;
+ u8 bCharFormat;
+ u8 bParityType;
+ u8 bDataBits;
+ u8 rate;
+ u8 unk;
+} __packed;
+
+#define CH348_MAXPORT 8
+
+/*
+ * The CH348 multiplexes rx & tx into a pair of Bulk USB endpoints for
+ * the 8 serial ports, and another pair of Bulk USB endpoints to
+ * set port settings and receive port status events.
+ *
+ * The USB serial cores ties every Bulk endpoints pairs to each ports,
+ * but in our case it will set port 0 with the rx/tx endpoints
+ * and port 1 with the setup/status endpoints.
+ *
+ * To still take advantage of the generic code, we (re-)initialize
+ * the USB serial port structure with the correct USB endpoint
+ * for read and write, and write proper process_read_urb()
+ * and prepare_write_buffer() to correctly (de-)multiplex data.
+ */
+
+/* struct ch348_ttyport - per-port information
+ * @uartmode UART port current mode
+ * @port: USB Serial Port structure
+ * @io_status: last reported I/O state
+ * @modem_status: last reported modem signals state
+ */
+struct ch348_ttyport {
+ u8 uartmode;
+ struct usb_serial_port *port;
+ unsigned int io_status;
+ unsigned int modem_status;
+};
+
+/* struct ch348 - main container for all this driver information
+ * @udev: pointer to the CH348 usb device
+ * @ttyport: List of per-port information
+ * @rx_endpoint: endpoint number for read operations
+ * @statusrx_endpoint: endpoint number for status operations
+ * @cmdtx_endpoint: endpoint number for configure operations
+ * @status_read_urb: URB for status
+ * @status_read_buffer: buffer used by status_read_urb
+ * @status_lock: control access of io_status/modem_status
+ * @readsize: packet size for bulk_in
+ * @writesize: packet size for bulk_out
+ */
+struct ch348 {
+ struct usb_device *udev;
+ struct ch348_ttyport ttyport[CH348_MAXPORT];
+
+ int rx_endpoint;
+ int tx_endpoint;
+ int statusrx_endpoint;
+ int cmdtx_endpoint;
+
+ struct urb *status_read_urb;
+ u8 *status_read_buffer;
+
+ spinlock_t status_lock;
+ int readsize;
+ int writesize;
+};
+
+struct ch348_magic {
+ u8 action;
+ u8 reg;
+ u8 control;
+} __packed;
+
+/* Some values came from vendor tree, and we have no meaning for them, this
+ * function simply use them.
+ */
+static int ch348_do_magic(struct ch348 *ch348, int portnum, u8 action, u8 reg, u8 control)
+{
+ int ret = 0, len;
+ struct ch348_magic *buffer;
+
+ buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
+ if (!buffer)
+ return -ENOMEM;
+
+ if (portnum < 4)
+ reg += 0x10 * portnum;
+ else
+ reg += 0x10 * (portnum - 4) + 0x08;
+
+ buffer->action = action;
+ buffer->reg = reg;
+ buffer->control = control;
+
+ ret = usb_bulk_msg(ch348->udev, ch348->cmdtx_endpoint, buffer, 3, &len,
+ DEFAULT_TIMEOUT);
+ if (ret)
+ dev_err(&ch348->udev->dev, "%s usb_bulk_msg err=%d\n", __func__, ret);
+
+ kfree(buffer);
+ return ret;
+}
+
+static int ch348_configure(struct ch348 *ch348, int portnum)
+{
+ int ret;
+
+ ret = ch348_do_magic(ch348, portnum, CMD_W_R, R_C2, 0x87);
+ if (ret)
+ return ret;
+ ret = ch348_do_magic(ch348, portnum, CMD_W_R, R_C4, 0x08);
+ return ret;
+}
+
+static void ch348_process_read_urb(struct urb *urb)
+{
+ struct usb_serial_port *port = urb->context;
+ struct ch348 *ch348 = usb_get_serial_data(port->serial);
+ u8 *buffer = urb->transfer_buffer, *end;
+ unsigned int portnum, usblen;
+ struct ch348_rxbuf *rxb;
+
+ if (!urb->actual_length) {
+ dev_warn(&port->dev, "%s:%d empty rx buffer\n", __func__, __LINE__);
+ return;
+ }
+
+ end = buffer + urb->actual_length;
+
+ for (; buffer < end; buffer += CH348_RX_PORT_CHUNK_LENGTH) {
+ rxb = (struct ch348_rxbuf *)buffer;
+ portnum = rxb->port;
+ if (portnum >= CH348_MAXPORT) {
+ dev_warn(&port->dev, "%s:%d invalid port %d\n",
+ __func__, __LINE__, portnum);
+ break;
+ }
+
+ usblen = rxb->length;
+ if (usblen > 30) {
+ dev_warn(&port->dev, "%s:%d invalid length %d for port %d\n",
+ __func__, __LINE__, usblen, portnum);
+ break;
+ }
+
+ port = ch348->ttyport[portnum].port;
+ tty_insert_flip_string(&port->port, rxb->data, usblen);
+ tty_flip_buffer_push(&port->port);
+ port->icount.rx += usblen;
+ usb_serial_debug_data(&port->dev, __func__, usblen, rxb->data);
+ }
+}
+
+static int ch348_prepare_write_buffer(struct usb_serial_port *port, void *dest, size_t size)
+{
+ struct ch348_txbuf *rxt = dest;
+ const size_t txhdrsize = offsetof(struct ch348_txbuf, data);
+ int count;
+
+ count = kfifo_out_locked(&port->write_fifo, rxt->data,
+ size - txhdrsize, &port->lock);
+
+ rxt->port = port->port_number;
+ rxt->length = cpu_to_le16(count);
+
+ return count + txhdrsize;
+}
+
+static int ch348_set_uartmode(struct ch348 *ch348, int portnum, u8 index, u8 mode)
+{
+ int ret = 0;
+
+ if (ch348->ttyport[portnum].uartmode == M_NOR && mode == M_HF) {
+ ret = ch348_do_magic(ch348, portnum, CMD_W_BR, R_C4, 0x51);
+ if (ret)
+ return ret;
+ ch348->ttyport[portnum].uartmode = M_HF;
+ }
+
+ if (ch348->ttyport[portnum].uartmode == M_HF && mode == M_NOR) {
+ ret = ch348_do_magic(ch348, portnum, CMD_W_BR, R_C4, 0x50);
+ if (ret)
+ return ret;
+ ch348->ttyport[portnum].uartmode = M_NOR;
+ }
+ return 0;
+}
+
+static void ch348_set_termios(struct tty_struct *tty, struct usb_serial_port *port,
+ const struct ktermios *termios_old)
+{
+ struct ch348 *ch348 = usb_get_serial_data(port->serial);
+ int portnum = port->port_number;
+ struct ktermios *termios = &tty->termios;
+ int ret, sent;
+ __le32 dwDTERate;
+ u8 bCharFormat;
+ struct ch348_initbuf *buffer;
+
+ if (termios_old && !tty_termios_hw_change(&tty->termios, termios_old))
+ return;
+
+ buffer = kzalloc(sizeof(*buffer), GFP_KERNEL);
+ if (!buffer) {
+ if (termios_old)
+ tty->termios = *termios_old;
+ return;
+ }
+
+ dwDTERate = tty_get_baud_rate(tty);
+ /* test show no success on low baud and datasheet said it is not supported */
+ if (dwDTERate < 1200)
+ dwDTERate = DEFAULT_BAUD_RATE;
+ /* datasheet said it is not supported */
+ if (dwDTERate > 6000000)
+ dwDTERate = 6000000;
+
+ bCharFormat = termios->c_cflag & CSTOPB ? 2 : 1;
+
+ buffer->bParityType = termios->c_cflag & PARENB ?
+ (termios->c_cflag & PARODD ? 1 : 2) +
+ (termios->c_cflag & CMSPAR ? 2 : 0) : 0;
+
+ switch (termios->c_cflag & CSIZE) {
+ case CS5:
+ buffer->bDataBits = 5;
+ break;
+ case CS6:
+ buffer->bDataBits = 6;
+ break;
+ case CS7:
+ buffer->bDataBits = 7;
+ break;
+ case CS8:
+ default:
+ buffer->bDataBits = 8;
+ break;
+ }
+ buffer->cmd = CMD_WB_E | (portnum & 0x0F);
+ buffer->reg = R_INIT;
+ buffer->port = portnum;
+ buffer->dwDTERate = cpu_to_be32(le32_to_cpu(dwDTERate));
+ if (bCharFormat == 2)
+ buffer->bCharFormat = 0x02;
+ else if (bCharFormat == 1)
+ buffer->bCharFormat = 0x00;
+ buffer->rate = max_t(__le32, 5, DIV_ROUND_CLOSEST(10000 * 15, dwDTERate));
+ ret = usb_bulk_msg(ch348->udev, ch348->cmdtx_endpoint, buffer,
+ sizeof(*buffer), &sent, DEFAULT_TIMEOUT);
+ if (ret < 0) {
+ dev_err(&ch348->udev->dev, "%s usb_bulk_msg err=%d\n",
+ __func__, ret);
+ goto out;
+ }
+
+ ret = ch348_do_magic(ch348, portnum, CMD_W_R, R_C1, 0x0F);
+ if (ret < 0)
+ goto out;
+
+ if (C_CRTSCTS(tty))
+ ret = ch348_set_uartmode(ch348, portnum, portnum, M_HF);
+ else
+ ret = ch348_set_uartmode(ch348, portnum, portnum, M_NOR);
+
+out:
+ kfree(buffer);
+}
+
+static int ch348_open(struct tty_struct *tty, struct usb_serial_port *port)
+{
+ struct ch348 *ch348 = usb_get_serial_data(port->serial);
+ int rv;
+
+ if (tty)
+ ch348_set_termios(tty, port, NULL);
+
+ rv = ch348_configure(ch348, port->port_number);
+ if (rv)
+ pr_err("%s configure err\n", __func__);
+
+ rv = usb_serial_generic_open(tty, port);
+
+ return rv;
+}
+
+static int ch348_fixup_port_bulk_in(struct ch348 *ch348, struct usb_serial_port *port)
+{
+ int i;
+
+ /* Already Initialized */
+ if (port->bulk_in_size) {
+ port->bulk_in_endpointAddress = usb_pipeendpoint(ch348->rx_endpoint);
+
+ for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i)
+ usb_fill_bulk_urb(port->read_urbs[i], port->serial->dev,
+ ch348->rx_endpoint,
+ port->bulk_in_buffers[i], port->bulk_in_size,
+ usb_serial_generic_read_bulk_callback, port);
+ } else {
+ port->bulk_in_size = ch348->readsize;
+ port->bulk_in_endpointAddress = usb_pipeendpoint(ch348->rx_endpoint);
+
+ for (i = 0; i < ARRAY_SIZE(port->read_urbs); ++i) {
+ set_bit(i, &port->read_urbs_free);
+ port->read_urbs[i] = usb_alloc_urb(0, GFP_KERNEL);
+ if (!port->read_urbs[i])
+ return -ENOMEM;
+ port->bulk_in_buffers[i] = kmalloc(port->bulk_in_size, GFP_KERNEL);
+ if (!port->bulk_in_buffers[i])
+ return -ENOMEM;
+ usb_fill_bulk_urb(port->read_urbs[i], port->serial->dev,
+ ch348->rx_endpoint,
+ port->bulk_in_buffers[i], port->bulk_in_size,
+ usb_serial_generic_read_bulk_callback, port);
+ }
+
+ port->read_urb = port->read_urbs[0];
+ port->bulk_in_buffer = port->bulk_in_buffers[0];
+ }
+
+ return 0;
+}
+
+static int ch348_fixup_port_bulk_out(struct ch348 *ch348, struct usb_serial_port *port)
+{
+ int i;
+
+ /* Already Initialized */
+ if (port->bulk_out_size) {
+ port->bulk_out_endpointAddress = usb_pipeendpoint(ch348->tx_endpoint);
+
+ for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i)
+ usb_fill_bulk_urb(port->write_urbs[i], port->serial->dev,
+ ch348->tx_endpoint,
+ port->bulk_out_buffers[i], port->bulk_out_size,
+ usb_serial_generic_write_bulk_callback, port);
+ } else {
+ if (kfifo_alloc(&port->write_fifo, PAGE_SIZE, GFP_KERNEL))
+ return -ENOMEM;
+
+ port->bulk_out_size = ch348->writesize;
+ port->bulk_out_endpointAddress = usb_pipeendpoint(ch348->tx_endpoint);
+
+ for (i = 0; i < ARRAY_SIZE(port->write_urbs); ++i) {
+ set_bit(i, &port->write_urbs_free);
+ port->write_urbs[i] = usb_alloc_urb(0, GFP_KERNEL);
+ if (!port->write_urbs[i])
+ return -ENOMEM;
+ port->bulk_out_buffers[i] = kmalloc(port->bulk_out_size, GFP_KERNEL);
+ if (!port->bulk_out_buffers[i])
+ return -ENOMEM;
+ usb_fill_bulk_urb(port->write_urbs[i], port->serial->dev,
+ ch348->tx_endpoint,
+ port->bulk_out_buffers[i], port->bulk_out_size,
+ usb_serial_generic_write_bulk_callback, port);
+ }
+
+ port->write_urb = port->write_urbs[0];
+ port->bulk_out_buffer = port->bulk_out_buffers[0];
+ }
+
+ return 0;
+}
+
+static int ch348_attach(struct usb_serial *serial)
+{
+ struct ch348 *ch348 = usb_get_serial_data(serial);
+ int i, ret;
+
+ /* Fixup Bulk OUT and IN endpoints */
+ for (i = 0; i < serial->num_port_pointers; ++i) {
+ ret = ch348_fixup_port_bulk_out(ch348, serial->port[i]);
+ if (ret)
+ return ret;
+ ret = ch348_fixup_port_bulk_in(ch348, serial->port[i]);
+ if (ret)
+ return ret;
+ }
+
+ return usb_submit_urb(ch348->status_read_urb, GFP_KERNEL);
+}
+
+static void ch348_update_io_status(struct ch348 *ch348, unsigned int portnum, u8 data)
+{
+ u8 diff;
+
+ if (portnum >= CH348_MAXPORT)
+ return;
+
+ data &= (CH348_LO | CH348_LP | CH348_LF | CH348_LB);
+
+ spin_lock(&ch348->status_lock);
+ diff = data ^ ch348->ttyport[portnum].io_status;
+ ch348->ttyport[portnum].io_status = data;
+ spin_unlock(&ch348->status_lock);
+
+ if (!diff)
+ return;
+
+ if (diff & CH348_LO)
+ ch348->ttyport[portnum].port->icount.overrun++;
+ if (diff & CH348_LP)
+ ch348->ttyport[portnum].port->icount.parity++;
+ if (diff & CH348_LF)
+ ch348->ttyport[portnum].port->icount.frame++;
+ if (diff & CH348_LB)
+ ch348->ttyport[portnum].port->icount.brk++;
+
+ wake_up_interruptible(&ch348->ttyport[portnum].port->port.delta_msr_wait);
+}
+
+static void ch348_update_modem_status(struct ch348 *ch348, unsigned int portnum, u8 data)
+{
+ struct tty_struct *tty;
+ u8 diff;
+
+ if (portnum >= CH348_MAXPORT)
+ return;
+
+ data &= (CH348_CTI_C | CH348_CTI_DSR | CH348_CTI_R | CH348_CTI_DCD);
+
+ spin_lock(&ch348->status_lock);
+ diff = data ^ ch348->ttyport[portnum].modem_status;
+ ch348->ttyport[portnum].modem_status = data;
+ spin_unlock(&ch348->status_lock);
+
+ if (!diff)
+ return;
+
+ if (diff & CH348_CTI_C)
+ ch348->ttyport[portnum].port->icount.cts++;
+ if (diff & CH348_CTI_DSR)
+ ch348->ttyport[portnum].port->icount.dsr++;
+ if (diff & CH348_CTI_R)
+ ch348->ttyport[portnum].port->icount.rng++;
+ if (diff & CH348_CTI_DCD) {
+ ch348->ttyport[portnum].port->icount.dcd++;
+
+ tty = tty_port_tty_get(&ch348->ttyport[portnum].port->port);
+ if (tty) {
+ usb_serial_handle_dcd_change(ch348->ttyport[portnum].port, tty,
+ data & CH348_CTI_DCD);
+ tty_kref_put(tty);
+ }
+ }
+
+ wake_up_interruptible(&ch348->ttyport[portnum].port->port.delta_msr_wait);
+}
+
+static void ch348_update_status(struct ch348 *ch348, u8 *data, unsigned int len)
+{
+ u8 *end = data + len;
+ unsigned int portnum, reg;
+
+ for (; data < end; ) {
+ portnum = data[0] & 0xf;
+ reg = data[1];
+
+ if (reg == R_INIT) {
+ data += sizeof(struct ch348_initbuf);
+ continue;
+ }
+
+ if (reg >= R_MOD && reg <= R_IO_I) {
+ /* This signal is used by vendor driver to handle GPIO Interrupts */
+ dev_dbg(&ch348->udev->dev, "port%d: unhandled status %02x%02x\n",
+ portnum, data[2], data[3]);
+ data += 4;
+ continue;
+ }
+
+ if ((reg & 0xf) == R_II_B1) {
+ dev_dbg(&ch348->udev->dev, "port%d: uart io state %02x\n",
+ portnum, data[2]);
+ ch348_update_io_status(ch348, portnum, data[2]);
+ data += 3;
+ continue;
+ }
+
+ if ((reg & 0xf) == R_II_B2) {
+ /* This signal is used by vendor driver to aggregate multiple port TX */
+ dev_dbg(&ch348->udev->dev,
+ "port%d: unhandled Write Empty status\n", portnum);
+ data += 3;
+ continue;
+ }
+
+ if ((reg & 0xf) == R_II_B3) {
+ dev_dbg(&ch348->udev->dev, "port%d: modem status %02x\n", portnum, data[2]);
+ ch348_update_modem_status(ch348, portnum, data[2]);
+ data += 3;
+ continue;
+ }
+
+ dev_dbg(&ch348->udev->dev, "port%d: unknown status %02x\n", portnum, reg);
+ data += 3;
+ }
+}
+
+static void ch348_status_read_bulk_callback(struct urb *urb)
+{
+ struct ch348 *ch348 = urb->context;
+ u8 *data = urb->transfer_buffer;
+ unsigned int len = urb->actual_length;
+ int ret;
+
+ switch (urb->status) {
+ case 0:
+ /* success */
+ break;
+ case -ECONNRESET:
+ case -ENOENT:
+ case -ESHUTDOWN:
+ /* this urb is terminated, clean up */
+ dev_dbg(&ch348->udev->dev, "%s - urb shutting down: %d\n",
+ __func__, urb->status);
+ return;
+ default:
+ dev_dbg(&ch348->udev->dev, "%s - nonzero urb status: %d\n",
+ __func__, urb->status);
+ goto exit;
+ }
+
+ usb_serial_debug_data(&ch348->udev->dev, __func__, len, data);
+ ch348_update_status(ch348, data, len);
+
+exit:
+ ret = usb_submit_urb(urb, GFP_ATOMIC);
+ if (ret) {
+ dev_err(&ch348->udev->dev, "%s - usb_submit_urb failed: %d\n",
+ __func__, ret);
+ }
+}
+
+static int ch348_allocate_status_read(struct ch348 *ch348, struct usb_endpoint_descriptor *epd)
+{
+ int buffer_size = usb_endpoint_maxp(epd);
+
+ ch348->status_read_urb = usb_alloc_urb(0, GFP_KERNEL);
+ if (!ch348->status_read_urb)
+ return -ENOMEM;
+ ch348->status_read_buffer = kmalloc(buffer_size, GFP_KERNEL);
+ if (!ch348->status_read_buffer) {
+ usb_free_urb(ch348->status_read_urb);
+ return -ENOMEM;
+ }
+
+ usb_fill_bulk_urb(ch348->status_read_urb, ch348->udev,
+ ch348->statusrx_endpoint, ch348->status_read_buffer,
+ buffer_size, ch348_status_read_bulk_callback, ch348);
+
+ return 0;
+}
+
+static void ch348_release(struct usb_serial *serial)
+{
+ struct ch348 *ch348 = usb_get_serial_data(serial);
+
+ usb_kill_urb(ch348->status_read_urb);
+ usb_free_urb(ch348->status_read_urb);
+}
+
+static int ch348_probe(struct usb_serial *serial, const struct usb_device_id *id)
+{
+ struct usb_interface *intf;
+ struct usb_endpoint_descriptor *epcmdwrite = NULL;
+ struct usb_endpoint_descriptor *epstatusread = NULL;
+ struct usb_endpoint_descriptor *epread = NULL;
+ struct usb_endpoint_descriptor *epwrite = NULL;
+ struct usb_device *usb_dev = serial->dev;
+ struct ch348 *ch348;
+ int ret;
+
+ intf = usb_ifnum_to_if(usb_dev, 0);
+
+ ret = usb_find_common_endpoints(intf->cur_altsetting, &epread, &epwrite,
+ NULL, NULL);
+ if (ret) {
+ dev_err(&serial->dev->dev, "ERROR: failed to find basic endpoints ret=%d\n", ret);
+ return ret;
+ }
+ epstatusread = &intf->cur_altsetting->endpoint[2].desc;
+ epcmdwrite = &intf->cur_altsetting->endpoint[3].desc;
+
+ if (!usb_endpoint_is_bulk_in(epstatusread)) {
+ dev_err(&serial->dev->dev, "ERROR: missing second bulk in\n");
+ return -EINVAL;
+ }
+ if (!usb_endpoint_is_bulk_out(epcmdwrite)) {
+ dev_err(&serial->dev->dev, "ERROR: missing second bulk out\n");
+ return -EINVAL;
+ }
+
+ ch348 = devm_kzalloc(&serial->dev->dev, sizeof(*ch348), GFP_KERNEL);
+ if (!ch348)
+ return -ENOMEM;
+
+ usb_set_serial_data(serial, ch348);
+
+ ch348->readsize = usb_endpoint_maxp(epread);
+ ch348->writesize = usb_endpoint_maxp(epwrite);
+ ch348->udev = serial->dev;
+
+ spin_lock_init(&ch348->status_lock);
+
+ ch348->rx_endpoint = usb_rcvbulkpipe(usb_dev, epread->bEndpointAddress);
+ ch348->tx_endpoint = usb_sndbulkpipe(usb_dev, epwrite->bEndpointAddress);
+ ch348->cmdtx_endpoint = usb_sndbulkpipe(usb_dev, epcmdwrite->bEndpointAddress);
+ ch348->statusrx_endpoint = usb_rcvbulkpipe(usb_dev, epstatusread->bEndpointAddress);
+
+ ret = ch348_allocate_status_read(ch348, epstatusread);
+ if (ret)
+ return ret;
+ return 0;
+}
+
+static int ch348_port_probe(struct usb_serial_port *port)
+{
+ struct ch348 *ch348 = usb_get_serial_data(port->serial);
+
+ ch348->ttyport[port->port_number].port = port;
+
+ return 0;
+}
+
+static const struct usb_device_id ch348_ids[] = {
+ { USB_DEVICE(0x1a86, 0x55d9), },
+ { }
+};
+
+MODULE_DEVICE_TABLE(usb, ch348_ids);
+
+static struct usb_serial_driver ch348_device = {
+ .driver = {
+ .owner = THIS_MODULE,
+ .name = "ch348",
+ },
+ .id_table = ch348_ids,
+ .num_ports = CH348_MAXPORT,
+ .open = ch348_open,
+ .set_termios = ch348_set_termios,
+ .process_read_urb = ch348_process_read_urb,
+ .prepare_write_buffer = ch348_prepare_write_buffer,
+ .probe = ch348_probe,
+ .attach = ch348_attach,
+ .release = ch348_release,
+ .port_probe = ch348_port_probe,
+};
+
+static struct usb_serial_driver * const serial_drivers[] = {
+ &ch348_device, NULL
+};
+
+module_usb_serial_driver(serial_drivers, ch348_ids);
+
+MODULE_AUTHOR("Corentin Labbe <clabbe@xxxxxxxxxxxx>");
+MODULE_DESCRIPTION("USB CH348 Octo port serial converter driver");
+MODULE_LICENSE("GPL");
--
2.37.4