From c7877e1983f051cc267e1ec8c232a02d23c0a82a Mon Sep 17 00:00:00 2001 From: Greg Kroah-Hartman Date: Tue, 7 Apr 2009 11:56:32 -0700 Subject: [PATCH] Revert USB: usb-serial ch341: support for DTR/RTS/CTS Reverts commit 664d5df92e88b6ef091048a802b3750f4e989180 as the commit log information was not complete, and we didn't have a proper signed-off-by by the author of the original BSD code. Cc: Werner Cornelius Cc: Boris Hajduk Cc: Alan Cox Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/ch341.c | 374 +++++++------------------------------ 1 file changed, 72 insertions(+), 302 deletions(-) diff --git a/drivers/usb/serial/ch341.c b/drivers/usb/serial/ch341.c index ab4cc277aa65..d33d39d9b7e2 100644 --- a/drivers/usb/serial/ch341.c +++ b/drivers/usb/serial/ch341.c @@ -1,7 +1,5 @@ /* * Copyright 2007, Frank A Kingswood - * Copyright 2007, Werner Cornelius - * Copyright 2009, Boris Hajduk * * ch341.c implements a serial port driver for the Winchiphead CH341. * @@ -23,39 +21,9 @@ #include #include -#define DEFAULT_BAUD_RATE 9600 +#define DEFAULT_BAUD_RATE 2400 #define DEFAULT_TIMEOUT 1000 -/* flags for IO-Bits */ -#define CH341_BIT_RTS (1 << 6) -#define CH341_BIT_DTR (1 << 5) - -/******************************/ -/* interrupt pipe definitions */ -/******************************/ -/* always 4 interrupt bytes */ -/* first irq byte normally 0x08 */ -/* second irq byte base 0x7d + below */ -/* third irq byte base 0x94 + below */ -/* fourth irq byte normally 0xee */ - -/* second interrupt byte */ -#define CH341_MULT_STAT 0x04 /* multiple status since last interrupt event */ - -/* status returned in third interrupt answer byte, inverted in data - from irq */ -#define CH341_BIT_CTS 0x01 -#define CH341_BIT_DSR 0x02 -#define CH341_BIT_RI 0x04 -#define CH341_BIT_DCD 0x08 -#define CH341_BITS_MODEM_STAT 0x0f /* all bits */ - -/*******************************/ -/* baudrate calculation factor */ -/*******************************/ -#define CH341_BAUDBASE_FACTOR 1532620800 -#define CH341_BAUDBASE_DIVMAX 3 - static int debug; static struct usb_device_id id_table [] = { @@ -66,12 +34,9 @@ static struct usb_device_id id_table [] = { MODULE_DEVICE_TABLE(usb, id_table); struct ch341_private { - spinlock_t lock; /* access lock */ - wait_queue_head_t delta_msr_wait; /* wait queue for modem status */ - 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 multi_status_change; /* status changed multiple since last call */ + unsigned baud_rate; + u8 dtr; + u8 rts; }; static int ch341_control_out(struct usb_device *dev, u8 request, @@ -107,28 +72,37 @@ static int ch341_set_baudrate(struct usb_device *dev, { short a, b; int r; - unsigned long factor; - short divisor; dbg("ch341_set_baudrate(%d)", priv->baud_rate); - - if (!priv->baud_rate) + switch (priv->baud_rate) { + case 2400: + a = 0xd901; + b = 0x0038; + break; + case 4800: + a = 0x6402; + b = 0x001f; + break; + case 9600: + a = 0xb202; + b = 0x0013; + break; + case 19200: + a = 0xd902; + b = 0x000d; + break; + case 38400: + a = 0x6403; + b = 0x000a; + break; + case 115200: + a = 0xcc03; + b = 0x0008; + break; + default: return -EINVAL; - factor = (CH341_BAUDBASE_FACTOR / priv->baud_rate); - divisor = CH341_BAUDBASE_DIVMAX; - - while ((factor > 0xfff0) && divisor) { - factor >>= 3; - divisor--; } - if (factor > 0xfff0) - return -EINVAL; - - 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); @@ -136,18 +110,19 @@ static int ch341_set_baudrate(struct usb_device *dev, return r; } -static int ch341_set_handshake(struct usb_device *dev, u8 control) +static int ch341_set_handshake(struct usb_device *dev, + struct ch341_private *priv) { - dbg("ch341_set_handshake(0x%02x)", control); - return ch341_control_out(dev, 0xa4, ~control, 0); + dbg("ch341_set_handshake(%d,%d)", priv->dtr, priv->rts); + return ch341_control_out(dev, 0xa4, + ~((priv->dtr?1<<5:0)|(priv->rts?1<<6:0)), 0); } -static int ch341_get_status(struct usb_device *dev, struct ch341_private *priv) +static int ch341_get_status(struct usb_device *dev) { char *buffer; int r; const unsigned size = 8; - unsigned long flags; dbg("ch341_get_status()"); @@ -159,15 +134,10 @@ static int ch341_get_status(struct usb_device *dev, struct ch341_private *priv) 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; - priv->multi_status_change = 0; - spin_unlock_irqrestore(&priv->lock, flags); - } else - r = -EPROTO; + /* Not having the datasheet for the CH341, we ignore the bytes returned + * from the device. Return error if the device did not respond in time. + */ + r = 0; out: kfree(buffer); return r; @@ -210,7 +180,7 @@ static int ch341_configure(struct usb_device *dev, struct ch341_private *priv) goto out; /* expect 0xff 0xee */ - r = ch341_get_status(dev, priv); + r = ch341_get_status(dev); if (r < 0) goto out; @@ -222,12 +192,12 @@ static int ch341_configure(struct usb_device *dev, struct ch341_private *priv) if (r < 0) goto out; - r = ch341_set_handshake(dev, priv->line_control); + r = ch341_set_handshake(dev, priv); if (r < 0) goto out; /* expect 0x9f 0xee */ - r = ch341_get_status(dev, priv); + r = ch341_get_status(dev); out: kfree(buffer); return r; @@ -246,10 +216,9 @@ static int ch341_attach(struct usb_serial *serial) if (!priv) return -ENOMEM; - spin_lock_init(&priv->lock); - init_waitqueue_head(&priv->delta_msr_wait); priv->baud_rate = DEFAULT_BAUD_RATE; - priv->line_control = CH341_BIT_RTS | CH341_BIT_DTR; + priv->dtr = 1; + priv->rts = 1; r = ch341_configure(serial->dev, priv); if (r < 0) @@ -262,35 +231,6 @@ error: kfree(priv); return r; } -static void ch341_close(struct tty_struct *tty, struct usb_serial_port *port, - struct file *filp) -{ - struct ch341_private *priv = usb_get_serial_port_data(port); - unsigned long flags; - unsigned int c_cflag; - - dbg("%s - port %d", __func__, port->number); - - /* shutdown our urbs */ - dbg("%s - shutting down urbs", __func__); - usb_kill_urb(port->write_urb); - usb_kill_urb(port->read_urb); - usb_kill_urb(port->interrupt_in_urb); - - if (tty) { - c_cflag = tty->termios->c_cflag; - if (c_cflag & HUPCL) { - /* drop DTR and RTS */ - spin_lock_irqsave(&priv->lock, flags); - priv->line_control = 0; - spin_unlock_irqrestore(&priv->lock, flags); - ch341_set_handshake(port->serial->dev, 0); - } - } - wake_up_interruptible(&priv->delta_msr_wait); -} - - /* open this device, set default parameters */ static int ch341_open(struct tty_struct *tty, struct usb_serial_port *port, struct file *filp) @@ -302,13 +242,14 @@ static int ch341_open(struct tty_struct *tty, struct usb_serial_port *port, dbg("ch341_open()"); priv->baud_rate = DEFAULT_BAUD_RATE; - priv->line_control = CH341_BIT_RTS | CH341_BIT_DTR; + priv->dtr = 1; + priv->rts = 1; r = ch341_configure(serial->dev, priv); if (r) goto out; - r = ch341_set_handshake(serial->dev, priv->line_control); + r = ch341_set_handshake(serial->dev, priv); if (r) goto out; @@ -316,16 +257,6 @@ static int ch341_open(struct tty_struct *tty, struct usb_serial_port *port, if (r) goto out; - dbg("%s - submitting interrupt urb", __func__); - port->interrupt_in_urb->dev = serial->dev; - r = usb_submit_urb(port->interrupt_in_urb, GFP_KERNEL); - if (r) { - dev_err(&port->dev, "%s - failed submitting interrupt urb," - " error %d\n", __func__, r); - ch341_close(tty, port, NULL); - return -EPROTO; - } - r = usb_serial_generic_open(tty, port, filp); out: return r; @@ -339,194 +270,38 @@ 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; dbg("ch341_set_termios()"); - if (!tty || !tty->termios) - return; - baud_rate = tty_get_baud_rate(tty); - priv->baud_rate = baud_rate; - - 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); + switch (baud_rate) { + case 2400: + case 4800: + case 9600: + case 19200: + case 38400: + case 115200: + priv->baud_rate = baud_rate; + break; + default: + dbg("Rate %d not supported, using %d", + baud_rate, DEFAULT_BAUD_RATE); + priv->baud_rate = DEFAULT_BAUD_RATE; } - ch341_set_handshake(port->serial->dev, priv->line_control); + ch341_set_baudrate(port->serial->dev, priv); /* Unimplemented: * (cflag & CSIZE) : data bits [5, 8] * (cflag & PARENB) : parity {NONE, EVEN, ODD} * (cflag & CSTOPB) : stop bits [1, 2] */ -} - -static int ch341_tiocmset(struct tty_struct *tty, struct file *file, - unsigned int set, unsigned int clear) -{ - struct usb_serial_port *port = tty->driver_data; - struct ch341_private *priv = usb_get_serial_port_data(port); - unsigned long flags; - u8 control; - - spin_lock_irqsave(&priv->lock, flags); - if (set & TIOCM_RTS) - priv->line_control |= CH341_BIT_RTS; - if (set & TIOCM_DTR) - priv->line_control |= CH341_BIT_DTR; - if (clear & TIOCM_RTS) - priv->line_control &= ~CH341_BIT_RTS; - if (clear & TIOCM_DTR) - priv->line_control &= ~CH341_BIT_DTR; - control = priv->line_control; - spin_unlock_irqrestore(&priv->lock, flags); - - return ch341_set_handshake(port->serial->dev, control); -} - -static void ch341_read_int_callback(struct urb *urb) -{ - struct usb_serial_port *port = (struct usb_serial_port *) urb->context; - unsigned char *data = urb->transfer_buffer; - unsigned int actual_length = urb->actual_length; - int status; - - dbg("%s (%d)", __func__, port->number); - - switch (urb->status) { - case 0: - /* success */ - break; - case -ECONNRESET: - case -ENOENT: - case -ESHUTDOWN: - /* this urb is terminated, clean up */ - dbg("%s - urb shutting down with status: %d", __func__, - urb->status); - return; - default: - dbg("%s - nonzero urb status received: %d", __func__, - urb->status); - goto exit; - } - - usb_serial_debug_data(debug, &port->dev, __func__, - urb->actual_length, urb->transfer_buffer); - - if (actual_length >= 4) { - struct ch341_private *priv = usb_get_serial_port_data(port); - unsigned long flags; - - spin_lock_irqsave(&priv->lock, flags); - priv->line_status = (~(data[2])) & CH341_BITS_MODEM_STAT; - if ((data[1] & CH341_MULT_STAT)) - priv->multi_status_change = 1; - spin_unlock_irqrestore(&priv->lock, flags); - wake_up_interruptible(&priv->delta_msr_wait); - } - -exit: - status = usb_submit_urb(urb, GFP_ATOMIC); - if (status) - dev_err(&urb->dev->dev, - "%s - usb_submit_urb failed with result %d\n", - __func__, status); -} - -static int wait_modem_info(struct usb_serial_port *port, unsigned int arg) -{ - struct ch341_private *priv = usb_get_serial_port_data(port); - unsigned long flags; - u8 prevstatus; - u8 status; - u8 changed; - u8 multi_change = 0; - - spin_lock_irqsave(&priv->lock, flags); - prevstatus = priv->line_status; - priv->multi_status_change = 0; - spin_unlock_irqrestore(&priv->lock, flags); - - while (!multi_change) { - interruptible_sleep_on(&priv->delta_msr_wait); - /* see if a signal did it */ - if (signal_pending(current)) - return -ERESTARTSYS; - - spin_lock_irqsave(&priv->lock, flags); - status = priv->line_status; - multi_change = priv->multi_status_change; - spin_unlock_irqrestore(&priv->lock, flags); - - changed = prevstatus ^ status; - - if (((arg & TIOCM_RNG) && (changed & CH341_BIT_RI)) || - ((arg & TIOCM_DSR) && (changed & CH341_BIT_DSR)) || - ((arg & TIOCM_CD) && (changed & CH341_BIT_DCD)) || - ((arg & TIOCM_CTS) && (changed & CH341_BIT_CTS))) { - return 0; - } - prevstatus = status; - } - - return 0; -} - -/*static int ch341_ioctl(struct usb_serial_port *port, struct file *file,*/ -static int ch341_ioctl(struct tty_struct *tty, struct file *file, - unsigned int cmd, unsigned long arg) -{ - struct usb_serial_port *port = tty->driver_data; - dbg("%s (%d) cmd = 0x%04x", __func__, port->number, cmd); - - switch (cmd) { - case TIOCMIWAIT: - dbg("%s (%d) TIOCMIWAIT", __func__, port->number); - return wait_modem_info(port, arg); - - default: - dbg("%s not supported = 0x%04x", __func__, cmd); - break; - } - - return -ENOIOCTLCMD; -} - -static int ch341_tiocmget(struct tty_struct *tty, struct file *file) -{ - struct usb_serial_port *port = tty->driver_data; - struct ch341_private *priv = usb_get_serial_port_data(port); - unsigned long flags; - u8 mcr; - u8 status; - unsigned int result; - - dbg("%s (%d)", __func__, port->number); - - spin_lock_irqsave(&priv->lock, flags); - mcr = priv->line_control; - status = priv->line_status; - spin_unlock_irqrestore(&priv->lock, flags); - - result = ((mcr & CH341_BIT_DTR) ? TIOCM_DTR : 0) - | ((mcr & CH341_BIT_RTS) ? TIOCM_RTS : 0) - | ((status & CH341_BIT_CTS) ? TIOCM_CTS : 0) - | ((status & CH341_BIT_DSR) ? TIOCM_DSR : 0) - | ((status & CH341_BIT_RI) ? TIOCM_RI : 0) - | ((status & CH341_BIT_DCD) ? TIOCM_CD : 0); - - dbg("%s - result = %x", __func__, result); - return result; + /* Copy back the old hardware settings */ + tty_termios_copy_hw(tty->termios, old_termios); + /* And re-encode with the new baud */ + tty_encode_baud_rate(tty, baud_rate, baud_rate); } @@ -564,17 +339,12 @@ static struct usb_serial_driver ch341_device = { .owner = THIS_MODULE, .name = "ch341-uart", }, - .id_table = id_table, - .usb_driver = &ch341_driver, - .num_ports = 1, - .open = ch341_open, - .close = ch341_close, - .ioctl = ch341_ioctl, - .set_termios = ch341_set_termios, - .tiocmget = ch341_tiocmget, - .tiocmset = ch341_tiocmset, - .read_int_callback = ch341_read_int_callback, - .attach = ch341_attach, + .id_table = id_table, + .usb_driver = &ch341_driver, + .num_ports = 1, + .open = ch341_open, + .set_termios = ch341_set_termios, + .attach = ch341_attach, }; static int __init ch341_init(void) -- 2.20.1