diff options
Diffstat (limited to 'drivers/usb/serial/ch341.c')
| -rw-r--r-- | drivers/usb/serial/ch341.c | 207 |
1 files changed, 141 insertions, 66 deletions
diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c index f139488d0816..95aa5233726c 100644 --- a/drivers/usb/serial/ch341.c +++ b/drivers/usb/serial/ch341.c @@ -61,13 +61,26 @@ * the Net/FreeBSD uchcom.c driver by Takanori Watanabe. Domo arigato. */ +#define CH341_REQ_READ_VERSION 0x5F #define CH341_REQ_WRITE_REG 0x9A #define CH341_REQ_READ_REG 0x95 -#define CH341_REG_BREAK1 0x05 -#define CH341_REG_BREAK2 0x18 -#define CH341_NBREAK_BITS_REG1 0x01 -#define CH341_NBREAK_BITS_REG2 0x40 - +#define CH341_REQ_SERIAL_INIT 0xA1 +#define CH341_REQ_MODEM_CTRL 0xA4 + +#define CH341_REG_BREAK 0x05 +#define CH341_REG_LCR 0x18 +#define CH341_NBREAK_BITS 0x01 + +#define CH341_LCR_ENABLE_RX 0x80 +#define CH341_LCR_ENABLE_TX 0x40 +#define CH341_LCR_MARK_SPACE 0x20 +#define CH341_LCR_PAR_EVEN 0x10 +#define CH341_LCR_ENABLE_PAR 0x08 +#define CH341_LCR_STOP_BITS_2 0x04 +#define CH341_LCR_CS8 0x03 +#define CH341_LCR_CS7 0x02 +#define CH341_LCR_CS6 0x01 +#define CH341_LCR_CS5 0x00 static const struct usb_device_id id_table[] = { { USB_DEVICE(0x4348, 0x5523) }, @@ -82,6 +95,7 @@ struct ch341_private { unsigned baud_rate; /* set baud rate */ u8 line_control; /* set line control value RTS/DTR */ u8 line_status; /* active status of modem control inputs */ + u8 lcr; }; static void ch341_set_termios(struct tty_struct *tty, @@ -99,6 +113,8 @@ static int ch341_control_out(struct usb_device *dev, u8 request, r = usb_control_msg(dev, usb_sndctrlpipe(dev, 0), request, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT, value, index, NULL, 0, DEFAULT_TIMEOUT); + if (r < 0) + dev_err(&dev->dev, "failed to send control message: %d\n", r); return r; } @@ -116,13 +132,26 @@ static int ch341_control_in(struct usb_device *dev, r = usb_control_msg(dev, usb_rcvctrlpipe(dev, 0), request, USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN, value, index, buf, bufsize, DEFAULT_TIMEOUT); - return r; + if (r < bufsize) { + if (r >= 0) { + dev_err(&dev->dev, + "short control message received (%d < %u)\n", + r, bufsize); + r = -EIO; + } + + dev_err(&dev->dev, "failed to receive control message: %d\n", + r); + return r; + } + + return 0; } -static int ch341_set_baudrate(struct usb_device *dev, - struct ch341_private *priv) +static int ch341_set_baudrate_lcr(struct usb_device *dev, + struct ch341_private *priv, u8 lcr) { - short a, b; + short a; int r; unsigned long factor; short divisor; @@ -142,43 +171,47 @@ static int ch341_set_baudrate(struct usb_device *dev, factor = 0x10000 - factor; a = (factor & 0xff00) | divisor; - b = factor & 0xff; - r = ch341_control_out(dev, 0x9a, 0x1312, a); - if (!r) - r = ch341_control_out(dev, 0x9a, 0x0f2c, b); + /* + * CH341A buffers data until a full endpoint-size packet (32 bytes) + * has been received unless bit 7 is set. + */ + a |= BIT(7); + + r = ch341_control_out(dev, CH341_REQ_WRITE_REG, 0x1312, a); + if (r) + return r; + + r = ch341_control_out(dev, CH341_REQ_WRITE_REG, 0x2518, lcr); + if (r) + return r; return r; } static int ch341_set_handshake(struct usb_device *dev, u8 control) { - return ch341_control_out(dev, 0xa4, ~control, 0); + return ch341_control_out(dev, CH341_REQ_MODEM_CTRL, ~control, 0); } static int ch341_get_status(struct usb_device *dev, struct ch341_private *priv) { + const unsigned int size = 2; char *buffer; int r; - const unsigned size = 8; unsigned long flags; buffer = kmalloc(size, GFP_KERNEL); if (!buffer) return -ENOMEM; - r = ch341_control_in(dev, 0x95, 0x0706, 0, buffer, size); + r = ch341_control_in(dev, CH341_REQ_READ_REG, 0x0706, 0, buffer, size); if (r < 0) goto out; - /* setup the private status if available */ - if (r == 2) { - r = 0; - spin_lock_irqsave(&priv->lock, flags); - priv->line_status = (~(*buffer)) & CH341_BITS_MODEM_STAT; - spin_unlock_irqrestore(&priv->lock, flags); - } else - r = -EPROTO; + spin_lock_irqsave(&priv->lock, flags); + priv->line_status = (~(*buffer)) & CH341_BITS_MODEM_STAT; + spin_unlock_irqrestore(&priv->lock, flags); out: kfree(buffer); return r; @@ -188,33 +221,30 @@ out: kfree(buffer); static int ch341_configure(struct usb_device *dev, struct ch341_private *priv) { + const unsigned int size = 2; char *buffer; int r; - const unsigned size = 8; buffer = kmalloc(size, GFP_KERNEL); if (!buffer) return -ENOMEM; /* expect two bytes 0x27 0x00 */ - r = ch341_control_in(dev, 0x5f, 0, 0, buffer, size); + r = ch341_control_in(dev, CH341_REQ_READ_VERSION, 0, 0, buffer, size); if (r < 0) goto out; + dev_dbg(&dev->dev, "Chip version: 0x%02x\n", buffer[0]); - r = ch341_control_out(dev, 0xa1, 0, 0); - if (r < 0) - goto out; - - r = ch341_set_baudrate(dev, priv); + r = ch341_control_out(dev, CH341_REQ_SERIAL_INIT, 0, 0); if (r < 0) goto out; /* expect two bytes 0x56 0x00 */ - r = ch341_control_in(dev, 0x95, 0x2518, 0, buffer, size); + r = ch341_control_in(dev, CH341_REQ_READ_REG, 0x2518, 0, buffer, size); if (r < 0) goto out; - r = ch341_control_out(dev, 0x9a, 0x2518, 0x0050); + r = ch341_control_out(dev, CH341_REQ_WRITE_REG, 0x2518, 0x0050); if (r < 0) goto out; @@ -223,11 +253,7 @@ static int ch341_configure(struct usb_device *dev, struct ch341_private *priv) if (r < 0) goto out; - r = ch341_control_out(dev, 0xa1, 0x501f, 0xd90a); - if (r < 0) - goto out; - - r = ch341_set_baudrate(dev, priv); + r = ch341_set_baudrate_lcr(dev, priv, priv->lcr); if (r < 0) goto out; @@ -253,7 +279,6 @@ static int ch341_port_probe(struct usb_serial_port *port) spin_lock_init(&priv->lock); priv->baud_rate = DEFAULT_BAUD_RATE; - priv->line_control = CH341_BIT_RTS | CH341_BIT_DTR; r = ch341_configure(port->serial->dev, priv); if (r < 0) @@ -315,7 +340,7 @@ static int ch341_open(struct tty_struct *tty, struct usb_serial_port *port) r = ch341_configure(serial->dev, priv); if (r) - goto out; + return r; if (tty) ch341_set_termios(tty, port, NULL); @@ -325,12 +350,19 @@ static int ch341_open(struct tty_struct *tty, struct usb_serial_port *port) if (r) { dev_err(&port->dev, "%s - failed to submit interrupt urb: %d\n", __func__, r); - goto out; + return r; } r = usb_serial_generic_open(tty, port); + if (r) + goto err_kill_interrupt_urb; + + return 0; -out: return r; +err_kill_interrupt_urb: + usb_kill_urb(port->interrupt_in_urb); + + return r; } /* Old_termios contains the original termios settings and @@ -342,35 +374,69 @@ static void ch341_set_termios(struct tty_struct *tty, struct ch341_private *priv = usb_get_serial_port_data(port); unsigned baud_rate; unsigned long flags; + unsigned char ctrl; + int r; + + /* redundant changes may cause the chip to lose bytes */ + if (old_termios && !tty_termios_hw_change(&tty->termios, old_termios)) + return; baud_rate = tty_get_baud_rate(tty); - priv->baud_rate = baud_rate; + ctrl = CH341_LCR_ENABLE_RX | CH341_LCR_ENABLE_TX; + + switch (C_CSIZE(tty)) { + case CS5: + ctrl |= CH341_LCR_CS5; + break; + case CS6: + ctrl |= CH341_LCR_CS6; + break; + case CS7: + ctrl |= CH341_LCR_CS7; + break; + case CS8: + ctrl |= CH341_LCR_CS8; + break; + } + + if (C_PARENB(tty)) { + ctrl |= CH341_LCR_ENABLE_PAR; + if (C_PARODD(tty) == 0) + ctrl |= CH341_LCR_PAR_EVEN; + if (C_CMSPAR(tty)) + ctrl |= CH341_LCR_MARK_SPACE; + } + + if (C_CSTOPB(tty)) + ctrl |= CH341_LCR_STOP_BITS_2; if (baud_rate) { - spin_lock_irqsave(&priv->lock, flags); - priv->line_control |= (CH341_BIT_DTR | CH341_BIT_RTS); - spin_unlock_irqrestore(&priv->lock, flags); - ch341_set_baudrate(port->serial->dev, priv); - } else { - spin_lock_irqsave(&priv->lock, flags); - priv->line_control &= ~(CH341_BIT_DTR | CH341_BIT_RTS); - spin_unlock_irqrestore(&priv->lock, flags); + priv->baud_rate = baud_rate; + + r = ch341_set_baudrate_lcr(port->serial->dev, priv, ctrl); + if (r < 0 && old_termios) { + priv->baud_rate = tty_termios_baud_rate(old_termios); + tty_termios_copy_hw(&tty->termios, old_termios); + } else if (r == 0) { + priv->lcr = ctrl; + } } - ch341_set_handshake(port->serial->dev, priv->line_control); + spin_lock_irqsave(&priv->lock, flags); + if (C_BAUD(tty) == B0) + priv->line_control &= ~(CH341_BIT_DTR | CH341_BIT_RTS); + else if (old_termios && (old_termios->c_cflag & CBAUD) == B0) + priv->line_control |= (CH341_BIT_DTR | CH341_BIT_RTS); + spin_unlock_irqrestore(&priv->lock, flags); - /* Unimplemented: - * (cflag & CSIZE) : data bits [5, 8] - * (cflag & PARENB) : parity {NONE, EVEN, ODD} - * (cflag & CSTOPB) : stop bits [1, 2] - */ + ch341_set_handshake(port->serial->dev, priv->line_control); } static void ch341_break_ctl(struct tty_struct *tty, int break_state) { const uint16_t ch341_break_reg = - ((uint16_t) CH341_REG_BREAK2 << 8) | CH341_REG_BREAK1; + ((uint16_t) CH341_REG_LCR << 8) | CH341_REG_BREAK; struct usb_serial_port *port = tty->driver_data; int r; uint16_t reg_contents; @@ -391,12 +457,12 @@ static void ch341_break_ctl(struct tty_struct *tty, int break_state) __func__, break_reg[0], break_reg[1]); if (break_state != 0) { dev_dbg(&port->dev, "%s - Enter break state requested\n", __func__); - break_reg[0] &= ~CH341_NBREAK_BITS_REG1; - break_reg[1] &= ~CH341_NBREAK_BITS_REG2; + break_reg[0] &= ~CH341_NBREAK_BITS; + break_reg[1] &= ~CH341_LCR_ENABLE_TX; } else { dev_dbg(&port->dev, "%s - Leave break state requested\n", __func__); - break_reg[0] |= CH341_NBREAK_BITS_REG1; - break_reg[1] |= CH341_NBREAK_BITS_REG2; + break_reg[0] |= CH341_NBREAK_BITS; + break_reg[1] |= CH341_LCR_ENABLE_TX; } dev_dbg(&port->dev, "%s - New ch341 break register contents - reg1: %x, reg2: %x\n", __func__, break_reg[0], break_reg[1]); @@ -539,14 +605,23 @@ static int ch341_tiocmget(struct tty_struct *tty) static int ch341_reset_resume(struct usb_serial *serial) { - struct ch341_private *priv; - - priv = usb_get_serial_port_data(serial->port[0]); + struct usb_serial_port *port = serial->port[0]; + struct ch341_private *priv = usb_get_serial_port_data(port); + int ret; /* reconfigure ch341 serial port after bus-reset */ ch341_configure(serial->dev, priv); - return 0; + if (tty_port_initialized(&port->port)) { + ret = usb_submit_urb(port->interrupt_in_urb, GFP_NOIO); + if (ret) { + dev_err(&port->dev, "failed to submit interrupt urb: %d\n", + ret); + return ret; + } + } + + return usb_serial_generic_resume(serial); } static struct usb_serial_driver ch341_device = { |