linux/drivers/usb/serial/ch341.c
Tejun Heo 5a0e3ad6af include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h
percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files.  percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed.  Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability.  As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

  http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
  only the necessary includes are there.  ie. if only gfp is used,
  gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
  blocks and try to put the new include such that its order conforms
  to its surrounding.  It's put in the include block which contains
  core kernel includes, in the same order that the rest are ordered -
  alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
  doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
  because the file doesn't have fitting include block), it prints out
  an error message indicating which .h file needs to be added to the
  file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
   over 4000 files, deleting around 700 includes and adding ~480 gfp.h
   and ~3000 slab.h inclusions.  The script emitted errors for ~400
   files.

2. Each error was manually checked.  Some didn't need the inclusion,
   some needed manual addition while adding it to implementation .h or
   embedding .c file was more appropriate for others.  This step added
   inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
   from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
   e.g. lib/decompress_*.c used malloc/free() wrappers around slab
   APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
   editing them as sprinkling gfp.h and slab.h inclusions around .h
   files could easily lead to inclusion dependency hell.  Most gfp.h
   inclusion directives were ignored as stuff from gfp.h was usually
   wildly available and often used in preprocessor macros.  Each
   slab.h inclusion directive was examined and added manually as
   necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
   were fixed.  CONFIG_GCOV_KERNEL was turned off for all tests (as my
   distributed build env didn't work with gcov compiles) and a few
   more options had to be turned off depending on archs to make things
   build (like ipr on powerpc/64 which failed due to missing writeq).

   * x86 and x86_64 UP and SMP allmodconfig and a custom test config.
   * powerpc and powerpc64 SMP allmodconfig
   * sparc and sparc64 SMP allmodconfig
   * ia64 SMP allmodconfig
   * s390 SMP allmodconfig
   * alpha SMP allmodconfig
   * um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
   a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2010-03-30 22:02:32 +09:00

674 lines
17 KiB
C

/*
* Copyright 2007, Frank A Kingswood <frank@kingswood-consulting.co.uk>
* Copyright 2007, Werner Cornelius <werner@cornelius-consult.de>
* Copyright 2009, Boris Hajduk <boris@hajduk.org>
*
* ch341.c implements a serial port driver for the Winchiphead CH341.
*
* The CH341 device can be used to implement an RS232 asynchronous
* serial port, an IEEE-1284 parallel printer port or a memory-like
* interface. In all cases the CH341 supports an I2C interface as well.
* This driver only supports the asynchronous serial interface.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 as published by the Free Software Foundation.
*/
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/tty.h>
#include <linux/module.h>
#include <linux/slab.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include <linux/serial.h>
#include <asm/unaligned.h>
#define DEFAULT_BAUD_RATE 9600
#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
/* Break support - the information used to implement this was gleaned from
* the Net/FreeBSD uchcom.c driver by Takanori Watanabe. Domo arigato.
*/
#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
static int debug;
static const struct usb_device_id id_table[] = {
{ USB_DEVICE(0x4348, 0x5523) },
{ USB_DEVICE(0x1a86, 0x7523) },
{ },
};
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 */
};
static int ch341_control_out(struct usb_device *dev, u8 request,
u16 value, u16 index)
{
int r;
dbg("ch341_control_out(%02x,%02x,%04x,%04x)", USB_DIR_OUT|0x40,
(int)request, (int)value, (int)index);
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);
return r;
}
static int ch341_control_in(struct usb_device *dev,
u8 request, u16 value, u16 index,
char *buf, unsigned bufsize)
{
int r;
dbg("ch341_control_in(%02x,%02x,%04x,%04x,%p,%u)", USB_DIR_IN|0x40,
(int)request, (int)value, (int)index, buf, (int)bufsize);
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;
}
static int ch341_set_baudrate(struct usb_device *dev,
struct ch341_private *priv)
{
short a, b;
int r;
unsigned long factor;
short divisor;
dbg("ch341_set_baudrate(%d)", priv->baud_rate);
if (!priv->baud_rate)
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);
return r;
}
static int ch341_set_handshake(struct usb_device *dev, u8 control)
{
dbg("ch341_set_handshake(0x%02x)", control);
return ch341_control_out(dev, 0xa4, ~control, 0);
}
static int ch341_get_status(struct usb_device *dev, struct ch341_private *priv)
{
char *buffer;
int r;
const unsigned size = 8;
unsigned long flags;
dbg("ch341_get_status()");
buffer = kmalloc(size, GFP_KERNEL);
if (!buffer)
return -ENOMEM;
r = ch341_control_in(dev, 0x95, 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;
priv->multi_status_change = 0;
spin_unlock_irqrestore(&priv->lock, flags);
} else
r = -EPROTO;
out: kfree(buffer);
return r;
}
/* -------------------------------------------------------------------------- */
static int ch341_configure(struct usb_device *dev, struct ch341_private *priv)
{
char *buffer;
int r;
const unsigned size = 8;
dbg("ch341_configure()");
buffer = kmalloc(size, GFP_KERNEL);
if (!buffer)
return -ENOMEM;
/* expect two bytes 0x27 0x00 */
r = ch341_control_in(dev, 0x5f, 0, 0, buffer, size);
if (r < 0)
goto out;
r = ch341_control_out(dev, 0xa1, 0, 0);
if (r < 0)
goto out;
r = ch341_set_baudrate(dev, priv);
if (r < 0)
goto out;
/* expect two bytes 0x56 0x00 */
r = ch341_control_in(dev, 0x95, 0x2518, 0, buffer, size);
if (r < 0)
goto out;
r = ch341_control_out(dev, 0x9a, 0x2518, 0x0050);
if (r < 0)
goto out;
/* expect 0xff 0xee */
r = ch341_get_status(dev, 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);
if (r < 0)
goto out;
r = ch341_set_handshake(dev, priv->line_control);
if (r < 0)
goto out;
/* expect 0x9f 0xee */
r = ch341_get_status(dev, priv);
out: kfree(buffer);
return r;
}
/* allocate private data */
static int ch341_attach(struct usb_serial *serial)
{
struct ch341_private *priv;
int r;
dbg("ch341_attach()");
/* private data */
priv = kzalloc(sizeof(struct ch341_private), GFP_KERNEL);
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;
r = ch341_configure(serial->dev, priv);
if (r < 0)
goto error;
usb_set_serial_port_data(serial->port[0], priv);
return 0;
error: kfree(priv);
return r;
}
static int ch341_carrier_raised(struct usb_serial_port *port)
{
struct ch341_private *priv = usb_get_serial_port_data(port);
if (priv->line_status & CH341_BIT_DCD)
return 1;
return 0;
}
static void ch341_dtr_rts(struct usb_serial_port *port, int on)
{
struct ch341_private *priv = usb_get_serial_port_data(port);
unsigned long flags;
dbg("%s - port %d", __func__, port->number);
/* drop DTR and RTS */
spin_lock_irqsave(&priv->lock, flags);
if (on)
priv->line_control |= CH341_BIT_RTS | CH341_BIT_DTR;
else
priv->line_control &= ~(CH341_BIT_RTS | CH341_BIT_DTR);
spin_unlock_irqrestore(&priv->lock, flags);
ch341_set_handshake(port->serial->dev, priv->line_control);
wake_up_interruptible(&priv->delta_msr_wait);
}
static void ch341_close(struct usb_serial_port *port)
{
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);
}
/* open this device, set default parameters */
static int ch341_open(struct tty_struct *tty, struct usb_serial_port *port)
{
struct usb_serial *serial = port->serial;
struct ch341_private *priv = usb_get_serial_port_data(serial->port[0]);
int r;
dbg("ch341_open()");
priv->baud_rate = DEFAULT_BAUD_RATE;
r = ch341_configure(serial->dev, priv);
if (r)
goto out;
r = ch341_set_handshake(serial->dev, priv->line_control);
if (r)
goto out;
r = ch341_set_baudrate(serial->dev, priv);
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(port);
return -EPROTO;
}
r = usb_serial_generic_open(tty, port);
out: return r;
}
/* Old_termios contains the original termios settings and
* tty->termios contains the new setting to be used.
*/
static void ch341_set_termios(struct tty_struct *tty,
struct usb_serial_port *port, struct ktermios *old_termios)
{
struct ch341_private *priv = usb_get_serial_port_data(port);
unsigned baud_rate;
unsigned long flags;
dbg("ch341_set_termios()");
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);
}
ch341_set_handshake(port->serial->dev, priv->line_control);
/* Unimplemented:
* (cflag & CSIZE) : data bits [5, 8]
* (cflag & PARENB) : parity {NONE, EVEN, ODD}
* (cflag & CSTOPB) : stop bits [1, 2]
*/
}
static void ch341_break_ctl(struct tty_struct *tty, int break_state)
{
const uint16_t ch341_break_reg =
CH341_REG_BREAK1 | ((uint16_t) CH341_REG_BREAK2 << 8);
struct usb_serial_port *port = tty->driver_data;
int r;
uint16_t reg_contents;
uint8_t *break_reg;
dbg("%s()", __func__);
break_reg = kmalloc(2, GFP_KERNEL);
if (!break_reg) {
dev_err(&port->dev, "%s - kmalloc failed\n", __func__);
return;
}
r = ch341_control_in(port->serial->dev, CH341_REQ_READ_REG,
ch341_break_reg, 0, break_reg, 2);
if (r < 0) {
dev_err(&port->dev, "%s - USB control read error (%d)\n",
__func__, r);
goto out;
}
dbg("%s - initial ch341 break register contents - reg1: %x, reg2: %x",
__func__, break_reg[0], break_reg[1]);
if (break_state != 0) {
dbg("%s - Enter break state requested", __func__);
break_reg[0] &= ~CH341_NBREAK_BITS_REG1;
break_reg[1] &= ~CH341_NBREAK_BITS_REG2;
} else {
dbg("%s - Leave break state requested", __func__);
break_reg[0] |= CH341_NBREAK_BITS_REG1;
break_reg[1] |= CH341_NBREAK_BITS_REG2;
}
dbg("%s - New ch341 break register contents - reg1: %x, reg2: %x",
__func__, break_reg[0], break_reg[1]);
reg_contents = get_unaligned_le16(break_reg);
r = ch341_control_out(port->serial->dev, CH341_REQ_WRITE_REG,
ch341_break_reg, reg_contents);
if (r < 0)
dev_err(&port->dev, "%s - USB control write error (%d)\n",
__func__, r);
out:
kfree(break_reg);
}
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;
}
static int ch341_reset_resume(struct usb_interface *intf)
{
struct usb_device *dev = interface_to_usbdev(intf);
struct usb_serial *serial = NULL;
struct ch341_private *priv;
serial = usb_get_intfdata(intf);
priv = usb_get_serial_port_data(serial->port[0]);
/*reconfigure ch341 serial port after bus-reset*/
ch341_configure(dev, priv);
usb_serial_resume(intf);
return 0;
}
static struct usb_driver ch341_driver = {
.name = "ch341",
.probe = usb_serial_probe,
.disconnect = usb_serial_disconnect,
.suspend = usb_serial_suspend,
.resume = usb_serial_resume,
.reset_resume = ch341_reset_resume,
.id_table = id_table,
.no_dynamic_id = 1,
.supports_autosuspend = 1,
};
static struct usb_serial_driver ch341_device = {
.driver = {
.owner = THIS_MODULE,
.name = "ch341-uart",
},
.id_table = id_table,
.usb_driver = &ch341_driver,
.num_ports = 1,
.open = ch341_open,
.dtr_rts = ch341_dtr_rts,
.carrier_raised = ch341_carrier_raised,
.close = ch341_close,
.ioctl = ch341_ioctl,
.set_termios = ch341_set_termios,
.break_ctl = ch341_break_ctl,
.tiocmget = ch341_tiocmget,
.tiocmset = ch341_tiocmset,
.read_int_callback = ch341_read_int_callback,
.attach = ch341_attach,
};
static int __init ch341_init(void)
{
int retval;
retval = usb_serial_register(&ch341_device);
if (retval)
return retval;
retval = usb_register(&ch341_driver);
if (retval)
usb_serial_deregister(&ch341_device);
return retval;
}
static void __exit ch341_exit(void)
{
usb_deregister(&ch341_driver);
usb_serial_deregister(&ch341_device);
}
module_init(ch341_init);
module_exit(ch341_exit);
MODULE_LICENSE("GPL");
module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Debug enabled or not");
/* EOF ch341.c */