From 62d826c8ddafb0a55eb6c5255779ddb782dc5507 Mon Sep 17 00:00:00 2001 From: "bart.hartgers@gmail.com" Date: Wed, 28 Oct 2009 10:43:29 +0100 Subject: [PATCH] USB: ark3116: Callbacks for interrupt and bulk read Signed-off-by: Bart Hartgers Cc: Mike McCormack Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/ark3116.c | 194 +++++++++++++++++++++++++++++++++++ 1 file changed, 194 insertions(+) diff --git a/drivers/usb/serial/ark3116.c b/drivers/usb/serial/ark3116.c index a7c26990ec67..067daf4db646 100644 --- a/drivers/usb/serial/ark3116.c +++ b/drivers/usb/serial/ark3116.c @@ -605,6 +605,198 @@ static void ark3116_break_ctl(struct tty_struct *tty, int break_state) mutex_unlock(&priv->hw_lock); } +static void ark3116_update_msr(struct usb_serial_port *port, __u8 msr) +{ + struct ark3116_private *priv = usb_get_serial_port_data(port); + unsigned long flags; + + spin_lock_irqsave(&priv->status_lock, flags); + priv->msr = msr; + spin_unlock_irqrestore(&priv->status_lock, flags); + + if (msr & UART_MSR_ANY_DELTA) { + /* update input line counters */ + if (msr & UART_MSR_DCTS) + priv->icount.cts++; + if (msr & UART_MSR_DDSR) + priv->icount.dsr++; + if (msr & UART_MSR_DDCD) + priv->icount.dcd++; + if (msr & UART_MSR_TERI) + priv->icount.rng++; + wake_up_interruptible(&priv->delta_msr_wait); + } +} + +static void ark3116_update_lsr(struct usb_serial_port *port, __u8 lsr) +{ + struct ark3116_private *priv = usb_get_serial_port_data(port); + unsigned long flags; + + spin_lock_irqsave(&priv->status_lock, flags); + /* combine bits */ + priv->lsr |= lsr; + spin_unlock_irqrestore(&priv->status_lock, flags); + + if (lsr&UART_LSR_BRK_ERROR_BITS) { + if (lsr & UART_LSR_BI) + priv->icount.brk++; + if (lsr & UART_LSR_FE) + priv->icount.frame++; + if (lsr & UART_LSR_PE) + priv->icount.parity++; + if (lsr & UART_LSR_OE) + priv->icount.overrun++; + } +} + +static void ark3116_read_int_callback(struct urb *urb) +{ + struct usb_serial_port *port = urb->context; + int status = urb->status; + const __u8 *data = urb->transfer_buffer; + int result; + + switch (status) { + case -ECONNRESET: + case -ENOENT: + case -ESHUTDOWN: + /* this urb is terminated, clean up */ + dbg("%s - urb shutting down with status: %d", + __func__, status); + return; + default: + dbg("%s - nonzero urb status received: %d", + __func__, status); + break; + case 0: /* success */ + /* discovered this by trail and error... */ + if ((urb->actual_length == 4) && (data[0] == 0xe8)) { + const __u8 id = data[1]&UART_IIR_ID; + dbg("%s: iir=%02x", __func__, data[1]); + if (id == UART_IIR_MSI) { + dbg("%s: msr=%02x", __func__, data[3]); + ark3116_update_msr(port, data[3]); + break; + } else if (id == UART_IIR_RLSI) { + dbg("%s: lsr=%02x", __func__, data[2]); + ark3116_update_lsr(port, data[2]); + break; + } + } + /* + * Not sure what this data meant... + */ + usb_serial_debug_data(debug, &port->dev, + __func__, + urb->actual_length, + urb->transfer_buffer); + break; + } + + result = usb_submit_urb(urb, GFP_ATOMIC); + if (result) + dev_err(&urb->dev->dev, + "%s - Error %d submitting interrupt urb\n", + __func__, result); +} + + +/* Data comes in via the bulk (data) URB, erors/interrupts via the int URB. + * This means that we cannot be sure which data byte has an associated error + * condition, so we report an error for all data in the next bulk read. + * + * Actually, there might even be a window between the bulk data leaving the + * ark and reading/resetting the lsr in the read_bulk_callback where an + * interrupt for the next data block could come in. + * Without somekind of ordering on the ark, we would have to report the + * error for the next block of data as well... + * For now, let's pretend this can't happen. + */ + +static void send_to_tty(struct tty_struct *tty, + const unsigned char *chars, + size_t size, char flag) +{ + if (size == 0) + return; + if (flag == TTY_NORMAL) { + tty_insert_flip_string(tty, chars, size); + } else { + int i; + for (i = 0; i < size; ++i) + tty_insert_flip_char(tty, chars[i], flag); + } +} + +static void ark3116_read_bulk_callback(struct urb *urb) +{ + struct usb_serial_port *port = urb->context; + struct ark3116_private *priv = usb_get_serial_port_data(port); + const __u8 *data = urb->transfer_buffer; + int status = urb->status; + struct tty_struct *tty; + unsigned long flags; + int result; + char flag; + __u32 lsr; + + switch (status) { + case -ECONNRESET: + case -ENOENT: + case -ESHUTDOWN: + /* this urb is terminated, clean up */ + dbg("%s - urb shutting down with status: %d", + __func__, status); + return; + default: + dbg("%s - nonzero urb status received: %d", + __func__, status); + break; + case 0: /* success */ + + spin_lock_irqsave(&priv->status_lock, flags); + lsr = priv->lsr; + /* clear error bits */ + priv->lsr &= ~UART_LSR_BRK_ERROR_BITS; + spin_unlock_irqrestore(&priv->status_lock, flags); + + if (unlikely(lsr & UART_LSR_BI)) + flag = TTY_BREAK; + else if (unlikely(lsr & UART_LSR_PE)) + flag = TTY_PARITY; + else if (unlikely(lsr & UART_LSR_FE)) + flag = TTY_FRAME; + else + flag = TTY_NORMAL; + + tty = tty_port_tty_get(&port->port); + if (tty) { + tty_buffer_request_room(tty, urb->actual_length + 1); + /* overrun is special, not associated with a char */ + if (unlikely(lsr & UART_LSR_OE)) + tty_insert_flip_char(tty, 0, TTY_OVERRUN); + send_to_tty(tty, data, urb->actual_length, flag); + tty_flip_buffer_push(tty); + tty_kref_put(tty); + } + + /* Throttle the device if requested by tty */ + spin_lock_irqsave(&port->lock, flags); + port->throttled = port->throttle_req; + if (port->throttled) { + spin_unlock_irqrestore(&port->lock, flags); + return; + } else + spin_unlock_irqrestore(&port->lock, flags); + } + /* Continue reading from device */ + result = usb_submit_urb(urb, GFP_ATOMIC); + if (result) + dev_err(&urb->dev->dev, "%s - failed resubmitting" + " read urb, error %d\n", __func__, result); +} + static struct usb_driver ark3116_driver = { .name = "ark3116", .probe = usb_serial_probe, @@ -631,6 +823,8 @@ static struct usb_serial_driver ark3116_device = { .open = ark3116_open, .close = ark3116_close, .break_ctl = ark3116_break_ctl, + .read_int_callback = ark3116_read_int_callback, + .read_bulk_callback = ark3116_read_bulk_callback, }; static int __init ark3116_init(void) -- 2.39.5