linux/drivers/usb/serial/ti_usb_3410_5052.c

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/* vi: ts=8 sw=8
*
* TI 3410/5052 USB Serial Driver
*
* Copyright (C) 2004 Texas Instruments
*
* This driver is based on the Linux io_ti driver, which is
* Copyright (C) 2000-2002 Inside Out Networks
* Copyright (C) 2001-2002 Greg Kroah-Hartman
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* For questions or problems with this driver, contact Texas Instruments
* technical support, or Al Borchers <alborchers@steinerpoint.com>, or
* Peter Berger <pberger@brimson.com>.
*
* This driver needs this hotplug script in /etc/hotplug/usb/ti_usb_3410_5052
* or in /etc/hotplug.d/usb/ti_usb_3410_5052.hotplug to set the device
* configuration.
*
* #!/bin/bash
*
* BOOT_CONFIG=1
* ACTIVE_CONFIG=2
*
* if [[ "$ACTION" != "add" ]]
* then
* exit
* fi
*
* CONFIG_PATH=/sys${DEVPATH%/?*}/bConfigurationValue
*
* if [[ 0`cat $CONFIG_PATH` -ne $BOOT_CONFIG ]]
* then
* exit
* fi
*
* PRODUCT=${PRODUCT%/?*} # delete version
* VENDOR_ID=`printf "%d" 0x${PRODUCT%/?*}`
* PRODUCT_ID=`printf "%d" 0x${PRODUCT#*?/}`
*
* PARAM_PATH=/sys/module/ti_usb_3410_5052/parameters
*
* function scan() {
* s=$1
* shift
* for i
* do
* if [[ $s -eq $i ]]
* then
* return 0
* fi
* done
* return 1
* }
*
* IFS=$IFS,
*
* if (scan $VENDOR_ID 1105 `cat $PARAM_PATH/vendor_3410` &&
* scan $PRODUCT_ID 13328 `cat $PARAM_PATH/product_3410`) ||
* (scan $VENDOR_ID 1105 `cat $PARAM_PATH/vendor_5052` &&
* scan $PRODUCT_ID 20562 20818 20570 20575 `cat $PARAM_PATH/product_5052`)
* then
* echo $ACTIVE_CONFIG > $CONFIG_PATH
* fi
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/tty.h>
#include <linux/tty_driver.h>
#include <linux/tty_flip.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <linux/ioctl.h>
#include <linux/serial.h>
#include <linux/circ_buf.h>
#include <asm/uaccess.h>
#include <asm/semaphore.h>
#include <linux/usb.h>
#include <linux/usb/serial.h>
#include "ti_usb_3410_5052.h"
#include "ti_fw_3410.h" /* firmware image for 3410 */
#include "ti_fw_5052.h" /* firmware image for 5052 */
/* Defines */
#define TI_DRIVER_VERSION "v0.9"
#define TI_DRIVER_AUTHOR "Al Borchers <alborchers@steinerpoint.com>"
#define TI_DRIVER_DESC "TI USB 3410/5052 Serial Driver"
#define TI_FIRMWARE_BUF_SIZE 16284
#define TI_WRITE_BUF_SIZE 1024
#define TI_TRANSFER_TIMEOUT 2
#define TI_DEFAULT_LOW_LATENCY 0
#define TI_DEFAULT_CLOSING_WAIT 4000 /* in .01 secs */
/* supported setserial flags */
#define TI_SET_SERIAL_FLAGS (ASYNC_LOW_LATENCY)
/* read urb states */
#define TI_READ_URB_RUNNING 0
#define TI_READ_URB_STOPPING 1
#define TI_READ_URB_STOPPED 2
#define TI_EXTRA_VID_PID_COUNT 5
/* Structures */
struct ti_port {
int tp_is_open;
__u8 tp_msr;
__u8 tp_lsr;
__u8 tp_shadow_mcr;
__u8 tp_uart_mode; /* 232 or 485 modes */
unsigned int tp_uart_base_addr;
int tp_flags;
int tp_closing_wait;/* in .01 secs */
struct async_icount tp_icount;
wait_queue_head_t tp_msr_wait; /* wait for msr change */
wait_queue_head_t tp_write_wait;
struct ti_device *tp_tdev;
struct usb_serial_port *tp_port;
spinlock_t tp_lock;
int tp_read_urb_state;
int tp_write_urb_in_use;
struct circ_buf *tp_write_buf;
};
struct ti_device {
struct semaphore td_open_close_sem;
int td_open_port_count;
struct usb_serial *td_serial;
int td_is_3410;
int td_urb_error;
};
/* Function Declarations */
static int ti_startup(struct usb_serial *serial);
static void ti_shutdown(struct usb_serial *serial);
static int ti_open(struct usb_serial_port *port, struct file *file);
static void ti_close(struct usb_serial_port *port, struct file *file);
static int ti_write(struct usb_serial_port *port, const unsigned char *data,
int count);
static int ti_write_room(struct usb_serial_port *port);
static int ti_chars_in_buffer(struct usb_serial_port *port);
static void ti_throttle(struct usb_serial_port *port);
static void ti_unthrottle(struct usb_serial_port *port);
static int ti_ioctl(struct usb_serial_port *port, struct file *file, unsigned int cmd, unsigned long arg);
static void ti_set_termios(struct usb_serial_port *port,
struct termios *old_termios);
static int ti_tiocmget(struct usb_serial_port *port, struct file *file);
static int ti_tiocmset(struct usb_serial_port *port, struct file *file,
unsigned int set, unsigned int clear);
static void ti_break(struct usb_serial_port *port, int break_state);
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 13:55:46 +00:00
static void ti_interrupt_callback(struct urb *urb);
static void ti_bulk_in_callback(struct urb *urb);
static void ti_bulk_out_callback(struct urb *urb);
static void ti_recv(struct device *dev, struct tty_struct *tty,
unsigned char *data, int length);
static void ti_send(struct ti_port *tport);
static int ti_set_mcr(struct ti_port *tport, unsigned int mcr);
static int ti_get_lsr(struct ti_port *tport);
static int ti_get_serial_info(struct ti_port *tport,
struct serial_struct __user *ret_arg);
static int ti_set_serial_info(struct ti_port *tport,
struct serial_struct __user *new_arg);
static void ti_handle_new_msr(struct ti_port *tport, __u8 msr);
static void ti_drain(struct ti_port *tport, unsigned long timeout, int flush);
static void ti_stop_read(struct ti_port *tport, struct tty_struct *tty);
static int ti_restart_read(struct ti_port *tport, struct tty_struct *tty);
static int ti_command_out_sync(struct ti_device *tdev, __u8 command,
__u16 moduleid, __u16 value, __u8 *data, int size);
static int ti_command_in_sync(struct ti_device *tdev, __u8 command,
__u16 moduleid, __u16 value, __u8 *data, int size);
static int ti_write_byte(struct ti_device *tdev, unsigned long addr,
__u8 mask, __u8 byte);
static int ti_download_firmware(struct ti_device *tdev,
unsigned char *firmware, unsigned int firmware_size);
/* circular buffer */
static struct circ_buf *ti_buf_alloc(void);
static void ti_buf_free(struct circ_buf *cb);
static void ti_buf_clear(struct circ_buf *cb);
static int ti_buf_data_avail(struct circ_buf *cb);
static int ti_buf_space_avail(struct circ_buf *cb);
static int ti_buf_put(struct circ_buf *cb, const char *buf, int count);
static int ti_buf_get(struct circ_buf *cb, char *buf, int count);
/* Data */
/* module parameters */
static int debug;
static int low_latency = TI_DEFAULT_LOW_LATENCY;
static int closing_wait = TI_DEFAULT_CLOSING_WAIT;
static ushort vendor_3410[TI_EXTRA_VID_PID_COUNT];
static int vendor_3410_count;
static ushort product_3410[TI_EXTRA_VID_PID_COUNT];
static int product_3410_count;
static ushort vendor_5052[TI_EXTRA_VID_PID_COUNT];
static int vendor_5052_count;
static ushort product_5052[TI_EXTRA_VID_PID_COUNT];
static int product_5052_count;
/* supported devices */
/* the array dimension is the number of default entries plus */
/* TI_EXTRA_VID_PID_COUNT user defined entries plus 1 terminating */
/* null entry */
static struct usb_device_id ti_id_table_3410[1+TI_EXTRA_VID_PID_COUNT+1] = {
{ USB_DEVICE(TI_VENDOR_ID, TI_3410_PRODUCT_ID) },
{ USB_DEVICE(TI_VENDOR_ID, TI_3410_EZ430_ID) },
};
static struct usb_device_id ti_id_table_5052[4+TI_EXTRA_VID_PID_COUNT+1] = {
{ USB_DEVICE(TI_VENDOR_ID, TI_5052_BOOT_PRODUCT_ID) },
{ USB_DEVICE(TI_VENDOR_ID, TI_5152_BOOT_PRODUCT_ID) },
{ USB_DEVICE(TI_VENDOR_ID, TI_5052_EEPROM_PRODUCT_ID) },
{ USB_DEVICE(TI_VENDOR_ID, TI_5052_FIRMWARE_PRODUCT_ID) },
};
static struct usb_device_id ti_id_table_combined[] = {
{ USB_DEVICE(TI_VENDOR_ID, TI_3410_PRODUCT_ID) },
{ USB_DEVICE(TI_VENDOR_ID, TI_3410_EZ430_ID) },
{ USB_DEVICE(TI_VENDOR_ID, TI_5052_BOOT_PRODUCT_ID) },
{ USB_DEVICE(TI_VENDOR_ID, TI_5152_BOOT_PRODUCT_ID) },
{ USB_DEVICE(TI_VENDOR_ID, TI_5052_EEPROM_PRODUCT_ID) },
{ USB_DEVICE(TI_VENDOR_ID, TI_5052_FIRMWARE_PRODUCT_ID) },
{ }
};
static struct usb_driver ti_usb_driver = {
.name = "ti_usb_3410_5052",
.probe = usb_serial_probe,
.disconnect = usb_serial_disconnect,
.id_table = ti_id_table_combined,
.no_dynamic_id = 1,
};
static struct usb_serial_driver ti_1port_device = {
.driver = {
.owner = THIS_MODULE,
.name = "ti_usb_3410_5052_1",
},
.description = "TI USB 3410 1 port adapter",
.id_table = ti_id_table_3410,
.num_interrupt_in = 1,
.num_bulk_in = 1,
.num_bulk_out = 1,
.num_ports = 1,
.attach = ti_startup,
.shutdown = ti_shutdown,
.open = ti_open,
.close = ti_close,
.write = ti_write,
.write_room = ti_write_room,
.chars_in_buffer = ti_chars_in_buffer,
.throttle = ti_throttle,
.unthrottle = ti_unthrottle,
.ioctl = ti_ioctl,
.set_termios = ti_set_termios,
.tiocmget = ti_tiocmget,
.tiocmset = ti_tiocmset,
.break_ctl = ti_break,
.read_int_callback = ti_interrupt_callback,
.read_bulk_callback = ti_bulk_in_callback,
.write_bulk_callback = ti_bulk_out_callback,
};
static struct usb_serial_driver ti_2port_device = {
.driver = {
.owner = THIS_MODULE,
.name = "ti_usb_3410_5052_2",
},
.description = "TI USB 5052 2 port adapter",
.id_table = ti_id_table_5052,
.num_interrupt_in = 1,
.num_bulk_in = 2,
.num_bulk_out = 2,
.num_ports = 2,
.attach = ti_startup,
.shutdown = ti_shutdown,
.open = ti_open,
.close = ti_close,
.write = ti_write,
.write_room = ti_write_room,
.chars_in_buffer = ti_chars_in_buffer,
.throttle = ti_throttle,
.unthrottle = ti_unthrottle,
.ioctl = ti_ioctl,
.set_termios = ti_set_termios,
.tiocmget = ti_tiocmget,
.tiocmset = ti_tiocmset,
.break_ctl = ti_break,
.read_int_callback = ti_interrupt_callback,
.read_bulk_callback = ti_bulk_in_callback,
.write_bulk_callback = ti_bulk_out_callback,
};
/* Module */
MODULE_AUTHOR(TI_DRIVER_AUTHOR);
MODULE_DESCRIPTION(TI_DRIVER_DESC);
MODULE_VERSION(TI_DRIVER_VERSION);
MODULE_LICENSE("GPL");
module_param(debug, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(debug, "Enable debugging, 0=no, 1=yes");
module_param(low_latency, bool, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(low_latency, "TTY low_latency flag, 0=off, 1=on, default is off");
module_param(closing_wait, int, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(closing_wait, "Maximum wait for data to drain in close, in .01 secs, default is 4000");
module_param_array(vendor_3410, ushort, &vendor_3410_count, S_IRUGO);
MODULE_PARM_DESC(vendor_3410, "Vendor ids for 3410 based devices, 1-5 short integers");
module_param_array(product_3410, ushort, &product_3410_count, S_IRUGO);
MODULE_PARM_DESC(product_3410, "Product ids for 3410 based devices, 1-5 short integers");
module_param_array(vendor_5052, ushort, &vendor_5052_count, S_IRUGO);
MODULE_PARM_DESC(vendor_5052, "Vendor ids for 5052 based devices, 1-5 short integers");
module_param_array(product_5052, ushort, &product_5052_count, S_IRUGO);
MODULE_PARM_DESC(product_5052, "Product ids for 5052 based devices, 1-5 short integers");
MODULE_DEVICE_TABLE(usb, ti_id_table_combined);
/* Functions */
static int __init ti_init(void)
{
int i,j;
int ret;
/* insert extra vendor and product ids */
j = ARRAY_SIZE(ti_id_table_3410) - TI_EXTRA_VID_PID_COUNT - 1;
for (i=0; i<min(vendor_3410_count,product_3410_count); i++,j++) {
ti_id_table_3410[j].idVendor = vendor_3410[i];
ti_id_table_3410[j].idProduct = product_3410[i];
ti_id_table_3410[j].match_flags = USB_DEVICE_ID_MATCH_DEVICE;
}
j = ARRAY_SIZE(ti_id_table_5052) - TI_EXTRA_VID_PID_COUNT - 1;
for (i=0; i<min(vendor_5052_count,product_5052_count); i++,j++) {
ti_id_table_5052[j].idVendor = vendor_5052[i];
ti_id_table_5052[j].idProduct = product_5052[i];
ti_id_table_5052[j].match_flags = USB_DEVICE_ID_MATCH_DEVICE;
}
ret = usb_serial_register(&ti_1port_device);
if (ret)
goto failed_1port;
ret = usb_serial_register(&ti_2port_device);
if (ret)
goto failed_2port;
ret = usb_register(&ti_usb_driver);
if (ret)
goto failed_usb;
info(TI_DRIVER_DESC " " TI_DRIVER_VERSION);
return 0;
failed_usb:
usb_serial_deregister(&ti_2port_device);
failed_2port:
usb_serial_deregister(&ti_1port_device);
failed_1port:
return ret;
}
static void __exit ti_exit(void)
{
usb_serial_deregister(&ti_1port_device);
usb_serial_deregister(&ti_2port_device);
usb_deregister(&ti_usb_driver);
}
module_init(ti_init);
module_exit(ti_exit);
static int ti_startup(struct usb_serial *serial)
{
struct ti_device *tdev;
struct ti_port *tport;
struct usb_device *dev = serial->dev;
int status;
int i;
dbg("%s - product 0x%4X, num configurations %d, configuration value %d",
__FUNCTION__, le16_to_cpu(dev->descriptor.idProduct),
dev->descriptor.bNumConfigurations,
dev->actconfig->desc.bConfigurationValue);
/* create device structure */
tdev = kzalloc(sizeof(struct ti_device), GFP_KERNEL);
if (tdev == NULL) {
dev_err(&dev->dev, "%s - out of memory\n", __FUNCTION__);
return -ENOMEM;
}
sema_init(&tdev->td_open_close_sem, 1);
tdev->td_serial = serial;
usb_set_serial_data(serial, tdev);
/* determine device type */
if (usb_match_id(serial->interface, ti_id_table_3410))
tdev->td_is_3410 = 1;
dbg("%s - device type is %s", __FUNCTION__, tdev->td_is_3410 ? "3410" : "5052");
/* if we have only 1 configuration, download firmware */
if (dev->descriptor.bNumConfigurations == 1) {
if (tdev->td_is_3410)
status = ti_download_firmware(tdev, ti_fw_3410,
sizeof(ti_fw_3410));
else
status = ti_download_firmware(tdev, ti_fw_5052,
sizeof(ti_fw_5052));
if (status)
goto free_tdev;
/* 3410 must be reset, 5052 resets itself */
if (tdev->td_is_3410) {
msleep_interruptible(100);
usb_reset_device(dev);
}
status = -ENODEV;
goto free_tdev;
}
/* the second configuration must be set (in sysfs by hotplug script) */
if (dev->actconfig->desc.bConfigurationValue == TI_BOOT_CONFIG) {
status = -ENODEV;
goto free_tdev;
}
/* set up port structures */
for (i = 0; i < serial->num_ports; ++i) {
tport = kmalloc(sizeof(struct ti_port), GFP_KERNEL);
if (tport == NULL) {
dev_err(&dev->dev, "%s - out of memory\n", __FUNCTION__);
status = -ENOMEM;
goto free_tports;
}
memset(tport, 0, sizeof(struct ti_port));
spin_lock_init(&tport->tp_lock);
tport->tp_uart_base_addr = (i == 0 ? TI_UART1_BASE_ADDR : TI_UART2_BASE_ADDR);
tport->tp_flags = low_latency ? ASYNC_LOW_LATENCY : 0;
tport->tp_closing_wait = closing_wait;
init_waitqueue_head(&tport->tp_msr_wait);
init_waitqueue_head(&tport->tp_write_wait);
tport->tp_write_buf = ti_buf_alloc();
if (tport->tp_write_buf == NULL) {
dev_err(&dev->dev, "%s - out of memory\n", __FUNCTION__);
kfree(tport);
status = -ENOMEM;
goto free_tports;
}
tport->tp_port = serial->port[i];
tport->tp_tdev = tdev;
usb_set_serial_port_data(serial->port[i], tport);
tport->tp_uart_mode = 0; /* default is RS232 */
}
return 0;
free_tports:
for (--i; i>=0; --i) {
tport = usb_get_serial_port_data(serial->port[i]);
ti_buf_free(tport->tp_write_buf);
kfree(tport);
usb_set_serial_port_data(serial->port[i], NULL);
}
free_tdev:
kfree(tdev);
usb_set_serial_data(serial, NULL);
return status;
}
static void ti_shutdown(struct usb_serial *serial)
{
int i;
struct ti_device *tdev = usb_get_serial_data(serial);
struct ti_port *tport;
dbg("%s", __FUNCTION__);
for (i=0; i < serial->num_ports; ++i) {
tport = usb_get_serial_port_data(serial->port[i]);
if (tport) {
ti_buf_free(tport->tp_write_buf);
kfree(tport);
usb_set_serial_port_data(serial->port[i], NULL);
}
}
kfree(tdev);
usb_set_serial_data(serial, NULL);
}
static int ti_open(struct usb_serial_port *port, struct file *file)
{
struct ti_port *tport = usb_get_serial_port_data(port);
struct ti_device *tdev;
struct usb_device *dev;
struct urb *urb;
int port_number;
int status;
__u16 open_settings = (__u8)(TI_PIPE_MODE_CONTINOUS |
TI_PIPE_TIMEOUT_ENABLE |
(TI_TRANSFER_TIMEOUT << 2));
dbg("%s - port %d", __FUNCTION__, port->number);
if (tport == NULL)
return -ENODEV;
dev = port->serial->dev;
tdev = tport->tp_tdev;
/* only one open on any port on a device at a time */
if (down_interruptible(&tdev->td_open_close_sem))
return -ERESTARTSYS;
if (port->tty)
port->tty->low_latency =
(tport->tp_flags & ASYNC_LOW_LATENCY) ? 1 : 0;
port_number = port->number - port->serial->minor;
memset(&(tport->tp_icount), 0x00, sizeof(tport->tp_icount));
tport->tp_msr = 0;
tport->tp_shadow_mcr |= (TI_MCR_RTS | TI_MCR_DTR);
/* start interrupt urb the first time a port is opened on this device */
if (tdev->td_open_port_count == 0) {
dbg("%s - start interrupt in urb", __FUNCTION__);
urb = tdev->td_serial->port[0]->interrupt_in_urb;
if (!urb) {
dev_err(&port->dev, "%s - no interrupt urb\n", __FUNCTION__);
status = -EINVAL;
goto up_sem;
}
urb->complete = ti_interrupt_callback;
urb->context = tdev;
urb->dev = dev;
status = usb_submit_urb(urb, GFP_KERNEL);
if (status) {
dev_err(&port->dev, "%s - submit interrupt urb failed, %d\n", __FUNCTION__, status);
goto up_sem;
}
}
ti_set_termios(port, NULL);
dbg("%s - sending TI_OPEN_PORT", __FUNCTION__);
status = ti_command_out_sync(tdev, TI_OPEN_PORT,
(__u8)(TI_UART1_PORT + port_number), open_settings, NULL, 0);
if (status) {
dev_err(&port->dev, "%s - cannot send open command, %d\n", __FUNCTION__, status);
goto unlink_int_urb;
}
dbg("%s - sending TI_START_PORT", __FUNCTION__);
status = ti_command_out_sync(tdev, TI_START_PORT,
(__u8)(TI_UART1_PORT + port_number), 0, NULL, 0);
if (status) {
dev_err(&port->dev, "%s - cannot send start command, %d\n", __FUNCTION__, status);
goto unlink_int_urb;
}
dbg("%s - sending TI_PURGE_PORT", __FUNCTION__);
status = ti_command_out_sync(tdev, TI_PURGE_PORT,
(__u8)(TI_UART1_PORT + port_number), TI_PURGE_INPUT, NULL, 0);
if (status) {
dev_err(&port->dev, "%s - cannot clear input buffers, %d\n", __FUNCTION__, status);
goto unlink_int_urb;
}
status = ti_command_out_sync(tdev, TI_PURGE_PORT,
(__u8)(TI_UART1_PORT + port_number), TI_PURGE_OUTPUT, NULL, 0);
if (status) {
dev_err(&port->dev, "%s - cannot clear output buffers, %d\n", __FUNCTION__, status);
goto unlink_int_urb;
}
/* reset the data toggle on the bulk endpoints to work around bug in
* host controllers where things get out of sync some times */
usb_clear_halt(dev, port->write_urb->pipe);
usb_clear_halt(dev, port->read_urb->pipe);
ti_set_termios(port, NULL);
dbg("%s - sending TI_OPEN_PORT (2)", __FUNCTION__);
status = ti_command_out_sync(tdev, TI_OPEN_PORT,
(__u8)(TI_UART1_PORT + port_number), open_settings, NULL, 0);
if (status) {
dev_err(&port->dev, "%s - cannot send open command (2), %d\n", __FUNCTION__, status);
goto unlink_int_urb;
}
dbg("%s - sending TI_START_PORT (2)", __FUNCTION__);
status = ti_command_out_sync(tdev, TI_START_PORT,
(__u8)(TI_UART1_PORT + port_number), 0, NULL, 0);
if (status) {
dev_err(&port->dev, "%s - cannot send start command (2), %d\n", __FUNCTION__, status);
goto unlink_int_urb;
}
/* start read urb */
dbg("%s - start read urb", __FUNCTION__);
urb = port->read_urb;
if (!urb) {
dev_err(&port->dev, "%s - no read urb\n", __FUNCTION__);
status = -EINVAL;
goto unlink_int_urb;
}
tport->tp_read_urb_state = TI_READ_URB_RUNNING;
urb->complete = ti_bulk_in_callback;
urb->context = tport;
urb->dev = dev;
status = usb_submit_urb(urb, GFP_KERNEL);
if (status) {
dev_err(&port->dev, "%s - submit read urb failed, %d\n", __FUNCTION__, status);
goto unlink_int_urb;
}
tport->tp_is_open = 1;
++tdev->td_open_port_count;
goto up_sem;
unlink_int_urb:
if (tdev->td_open_port_count == 0)
usb_kill_urb(port->serial->port[0]->interrupt_in_urb);
up_sem:
up(&tdev->td_open_close_sem);
dbg("%s - exit %d", __FUNCTION__, status);
return status;
}
static void ti_close(struct usb_serial_port *port, struct file *file)
{
struct ti_device *tdev;
struct ti_port *tport;
int port_number;
int status;
int do_up;
dbg("%s - port %d", __FUNCTION__, port->number);
tdev = usb_get_serial_data(port->serial);
tport = usb_get_serial_port_data(port);
if (tdev == NULL || tport == NULL)
return;
tport->tp_is_open = 0;
ti_drain(tport, (tport->tp_closing_wait*HZ)/100, 1);
usb_kill_urb(port->read_urb);
usb_kill_urb(port->write_urb);
tport->tp_write_urb_in_use = 0;
port_number = port->number - port->serial->minor;
dbg("%s - sending TI_CLOSE_PORT", __FUNCTION__);
status = ti_command_out_sync(tdev, TI_CLOSE_PORT,
(__u8)(TI_UART1_PORT + port_number), 0, NULL, 0);
if (status)
dev_err(&port->dev, "%s - cannot send close port command, %d\n" , __FUNCTION__, status);
/* if down is interrupted, continue anyway */
do_up = !down_interruptible(&tdev->td_open_close_sem);
--tport->tp_tdev->td_open_port_count;
if (tport->tp_tdev->td_open_port_count <= 0) {
/* last port is closed, shut down interrupt urb */
usb_kill_urb(port->serial->port[0]->interrupt_in_urb);
tport->tp_tdev->td_open_port_count = 0;
}
if (do_up)
up(&tdev->td_open_close_sem);
dbg("%s - exit", __FUNCTION__);
}
static int ti_write(struct usb_serial_port *port, const unsigned char *data,
int count)
{
struct ti_port *tport = usb_get_serial_port_data(port);
unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number);
if (count == 0) {
dbg("%s - write request of 0 bytes", __FUNCTION__);
return 0;
}
if (tport == NULL || !tport->tp_is_open)
return -ENODEV;
spin_lock_irqsave(&tport->tp_lock, flags);
count = ti_buf_put(tport->tp_write_buf, data, count);
spin_unlock_irqrestore(&tport->tp_lock, flags);
ti_send(tport);
return count;
}
static int ti_write_room(struct usb_serial_port *port)
{
struct ti_port *tport = usb_get_serial_port_data(port);
int room = 0;
unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number);
if (tport == NULL)
return -ENODEV;
spin_lock_irqsave(&tport->tp_lock, flags);
room = ti_buf_space_avail(tport->tp_write_buf);
spin_unlock_irqrestore(&tport->tp_lock, flags);
dbg("%s - returns %d", __FUNCTION__, room);
return room;
}
static int ti_chars_in_buffer(struct usb_serial_port *port)
{
struct ti_port *tport = usb_get_serial_port_data(port);
int chars = 0;
unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number);
if (tport == NULL)
return -ENODEV;
spin_lock_irqsave(&tport->tp_lock, flags);
chars = ti_buf_data_avail(tport->tp_write_buf);
spin_unlock_irqrestore(&tport->tp_lock, flags);
dbg("%s - returns %d", __FUNCTION__, chars);
return chars;
}
static void ti_throttle(struct usb_serial_port *port)
{
struct ti_port *tport = usb_get_serial_port_data(port);
struct tty_struct *tty;
dbg("%s - port %d", __FUNCTION__, port->number);
if (tport == NULL)
return;
tty = port->tty;
if (!tty) {
dbg("%s - no tty", __FUNCTION__);
return;
}
if (I_IXOFF(tty) || C_CRTSCTS(tty))
ti_stop_read(tport, tty);
}
static void ti_unthrottle(struct usb_serial_port *port)
{
struct ti_port *tport = usb_get_serial_port_data(port);
struct tty_struct *tty;
int status;
dbg("%s - port %d", __FUNCTION__, port->number);
if (tport == NULL)
return;
tty = port->tty;
if (!tty) {
dbg("%s - no tty", __FUNCTION__);
return;
}
if (I_IXOFF(tty) || C_CRTSCTS(tty)) {
status = ti_restart_read(tport, tty);
if (status)
dev_err(&port->dev, "%s - cannot restart read, %d\n", __FUNCTION__, status);
}
}
static int ti_ioctl(struct usb_serial_port *port, struct file *file,
unsigned int cmd, unsigned long arg)
{
struct ti_port *tport = usb_get_serial_port_data(port);
struct async_icount cnow;
struct async_icount cprev;
dbg("%s - port %d, cmd = 0x%04X", __FUNCTION__, port->number, cmd);
if (tport == NULL)
return -ENODEV;
switch (cmd) {
case TIOCGSERIAL:
dbg("%s - (%d) TIOCGSERIAL", __FUNCTION__, port->number);
return ti_get_serial_info(tport, (struct serial_struct __user *)arg);
break;
case TIOCSSERIAL:
dbg("%s - (%d) TIOCSSERIAL", __FUNCTION__, port->number);
return ti_set_serial_info(tport, (struct serial_struct __user *)arg);
break;
case TIOCMIWAIT:
dbg("%s - (%d) TIOCMIWAIT", __FUNCTION__, port->number);
cprev = tport->tp_icount;
while (1) {
interruptible_sleep_on(&tport->tp_msr_wait);
if (signal_pending(current))
return -ERESTARTSYS;
cnow = tport->tp_icount;
if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr &&
cnow.dcd == cprev.dcd && cnow.cts == cprev.cts)
return -EIO; /* no change => error */
if (((arg & TIOCM_RNG) && (cnow.rng != cprev.rng)) ||
((arg & TIOCM_DSR) && (cnow.dsr != cprev.dsr)) ||
((arg & TIOCM_CD) && (cnow.dcd != cprev.dcd)) ||
((arg & TIOCM_CTS) && (cnow.cts != cprev.cts)) ) {
return 0;
}
cprev = cnow;
}
break;
case TIOCGICOUNT:
dbg("%s - (%d) TIOCGICOUNT RX=%d, TX=%d", __FUNCTION__, port->number, tport->tp_icount.rx, tport->tp_icount.tx);
if (copy_to_user((void __user *)arg, &tport->tp_icount, sizeof(tport->tp_icount)))
return -EFAULT;
return 0;
}
return -ENOIOCTLCMD;
}
static void ti_set_termios(struct usb_serial_port *port,
struct termios *old_termios)
{
struct ti_port *tport = usb_get_serial_port_data(port);
struct tty_struct *tty = port->tty;
struct ti_uart_config *config;
tcflag_t cflag,iflag;
int baud;
int status;
int port_number = port->number - port->serial->minor;
unsigned int mcr;
dbg("%s - port %d", __FUNCTION__, port->number);
if (!tty || !tty->termios) {
dbg("%s - no tty or termios", __FUNCTION__);
return;
}
cflag = tty->termios->c_cflag;
iflag = tty->termios->c_iflag;
if (old_termios && cflag == old_termios->c_cflag
&& iflag == old_termios->c_iflag) {
dbg("%s - nothing to change", __FUNCTION__);
return;
}
dbg("%s - clfag %08x, iflag %08x", __FUNCTION__, cflag, iflag);
if (old_termios)
dbg("%s - old clfag %08x, old iflag %08x", __FUNCTION__, old_termios->c_cflag, old_termios->c_iflag);
if (tport == NULL)
return;
config = kmalloc(sizeof(*config), GFP_KERNEL);
if (!config) {
dev_err(&port->dev, "%s - out of memory\n", __FUNCTION__);
return;
}
config->wFlags = 0;
/* these flags must be set */
config->wFlags |= TI_UART_ENABLE_MS_INTS;
config->wFlags |= TI_UART_ENABLE_AUTO_START_DMA;
config->bUartMode = (__u8)(tport->tp_uart_mode);
switch (cflag & CSIZE) {
case CS5:
config->bDataBits = TI_UART_5_DATA_BITS;
break;
case CS6:
config->bDataBits = TI_UART_6_DATA_BITS;
break;
case CS7:
config->bDataBits = TI_UART_7_DATA_BITS;
break;
default:
case CS8:
config->bDataBits = TI_UART_8_DATA_BITS;
break;
}
if (cflag & PARENB) {
if (cflag & PARODD) {
config->wFlags |= TI_UART_ENABLE_PARITY_CHECKING;
config->bParity = TI_UART_ODD_PARITY;
} else {
config->wFlags |= TI_UART_ENABLE_PARITY_CHECKING;
config->bParity = TI_UART_EVEN_PARITY;
}
} else {
config->wFlags &= ~TI_UART_ENABLE_PARITY_CHECKING;
config->bParity = TI_UART_NO_PARITY;
}
if (cflag & CSTOPB)
config->bStopBits = TI_UART_2_STOP_BITS;
else
config->bStopBits = TI_UART_1_STOP_BITS;
if (cflag & CRTSCTS) {
/* RTS flow control must be off to drop RTS for baud rate B0 */
if ((cflag & CBAUD) != B0)
config->wFlags |= TI_UART_ENABLE_RTS_IN;
config->wFlags |= TI_UART_ENABLE_CTS_OUT;
} else {
tty->hw_stopped = 0;
ti_restart_read(tport, tty);
}
if (I_IXOFF(tty) || I_IXON(tty)) {
config->cXon = START_CHAR(tty);
config->cXoff = STOP_CHAR(tty);
if (I_IXOFF(tty))
config->wFlags |= TI_UART_ENABLE_X_IN;
else
ti_restart_read(tport, tty);
if (I_IXON(tty))
config->wFlags |= TI_UART_ENABLE_X_OUT;
}
baud = tty_get_baud_rate(tty);
if (!baud) baud = 9600;
if (tport->tp_tdev->td_is_3410)
config->wBaudRate = (__u16)((923077 + baud/2) / baud);
else
config->wBaudRate = (__u16)((461538 + baud/2) / baud);
dbg("%s - BaudRate=%d, wBaudRate=%d, wFlags=0x%04X, bDataBits=%d, bParity=%d, bStopBits=%d, cXon=%d, cXoff=%d, bUartMode=%d",
__FUNCTION__, baud, config->wBaudRate, config->wFlags, config->bDataBits, config->bParity, config->bStopBits, config->cXon, config->cXoff, config->bUartMode);
cpu_to_be16s(&config->wBaudRate);
cpu_to_be16s(&config->wFlags);
status = ti_command_out_sync(tport->tp_tdev, TI_SET_CONFIG,
(__u8)(TI_UART1_PORT + port_number), 0, (__u8 *)config,
sizeof(*config));
if (status)
dev_err(&port->dev, "%s - cannot set config on port %d, %d\n", __FUNCTION__, port_number, status);
/* SET_CONFIG asserts RTS and DTR, reset them correctly */
mcr = tport->tp_shadow_mcr;
/* if baud rate is B0, clear RTS and DTR */
if ((cflag & CBAUD) == B0)
mcr &= ~(TI_MCR_DTR | TI_MCR_RTS);
status = ti_set_mcr(tport, mcr);
if (status)
dev_err(&port->dev, "%s - cannot set modem control on port %d, %d\n", __FUNCTION__, port_number, status);
kfree(config);
}
static int ti_tiocmget(struct usb_serial_port *port, struct file *file)
{
struct ti_port *tport = usb_get_serial_port_data(port);
unsigned int result;
unsigned int msr;
unsigned int mcr;
dbg("%s - port %d", __FUNCTION__, port->number);
if (tport == NULL)
return -ENODEV;
msr = tport->tp_msr;
mcr = tport->tp_shadow_mcr;
result = ((mcr & TI_MCR_DTR) ? TIOCM_DTR : 0)
| ((mcr & TI_MCR_RTS) ? TIOCM_RTS : 0)
| ((mcr & TI_MCR_LOOP) ? TIOCM_LOOP : 0)
| ((msr & TI_MSR_CTS) ? TIOCM_CTS : 0)
| ((msr & TI_MSR_CD) ? TIOCM_CAR : 0)
| ((msr & TI_MSR_RI) ? TIOCM_RI : 0)
| ((msr & TI_MSR_DSR) ? TIOCM_DSR : 0);
dbg("%s - 0x%04X", __FUNCTION__, result);
return result;
}
static int ti_tiocmset(struct usb_serial_port *port, struct file *file,
unsigned int set, unsigned int clear)
{
struct ti_port *tport = usb_get_serial_port_data(port);
unsigned int mcr;
dbg("%s - port %d", __FUNCTION__, port->number);
if (tport == NULL)
return -ENODEV;
mcr = tport->tp_shadow_mcr;
if (set & TIOCM_RTS)
mcr |= TI_MCR_RTS;
if (set & TIOCM_DTR)
mcr |= TI_MCR_DTR;
if (set & TIOCM_LOOP)
mcr |= TI_MCR_LOOP;
if (clear & TIOCM_RTS)
mcr &= ~TI_MCR_RTS;
if (clear & TIOCM_DTR)
mcr &= ~TI_MCR_DTR;
if (clear & TIOCM_LOOP)
mcr &= ~TI_MCR_LOOP;
return ti_set_mcr(tport, mcr);
}
static void ti_break(struct usb_serial_port *port, int break_state)
{
struct ti_port *tport = usb_get_serial_port_data(port);
int status;
dbg("%s - state = %d", __FUNCTION__, break_state);
if (tport == NULL)
return;
ti_drain(tport, (tport->tp_closing_wait*HZ)/100, 0);
status = ti_write_byte(tport->tp_tdev,
tport->tp_uart_base_addr + TI_UART_OFFSET_LCR,
TI_LCR_BREAK, break_state == -1 ? TI_LCR_BREAK : 0);
if (status)
dbg("%s - error setting break, %d", __FUNCTION__, status);
}
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 13:55:46 +00:00
static void ti_interrupt_callback(struct urb *urb)
{
struct ti_device *tdev = (struct ti_device *)urb->context;
struct usb_serial_port *port;
struct usb_serial *serial = tdev->td_serial;
struct ti_port *tport;
struct device *dev = &urb->dev->dev;
unsigned char *data = urb->transfer_buffer;
int length = urb->actual_length;
int port_number;
int function;
int status;
__u8 msr;
dbg("%s", __FUNCTION__);
switch (urb->status) {
case 0:
break;
case -ECONNRESET:
case -ENOENT:
case -ESHUTDOWN:
dbg("%s - urb shutting down, %d", __FUNCTION__, urb->status);
tdev->td_urb_error = 1;
return;
default:
dev_err(dev, "%s - nonzero urb status, %d\n", __FUNCTION__, urb->status);
tdev->td_urb_error = 1;
goto exit;
}
if (length != 2) {
dbg("%s - bad packet size, %d", __FUNCTION__, length);
goto exit;
}
if (data[0] == TI_CODE_HARDWARE_ERROR) {
dev_err(dev, "%s - hardware error, %d\n", __FUNCTION__, data[1]);
goto exit;
}
port_number = TI_GET_PORT_FROM_CODE(data[0]);
function = TI_GET_FUNC_FROM_CODE(data[0]);
dbg("%s - port_number %d, function %d, data 0x%02X", __FUNCTION__, port_number, function, data[1]);
if (port_number >= serial->num_ports) {
dev_err(dev, "%s - bad port number, %d\n", __FUNCTION__, port_number);
goto exit;
}
port = serial->port[port_number];
tport = usb_get_serial_port_data(port);
if (!tport)
goto exit;
switch (function) {
case TI_CODE_DATA_ERROR:
dev_err(dev, "%s - DATA ERROR, port %d, data 0x%02X\n", __FUNCTION__, port_number, data[1]);
break;
case TI_CODE_MODEM_STATUS:
msr = data[1];
dbg("%s - port %d, msr 0x%02X", __FUNCTION__, port_number, msr);
ti_handle_new_msr(tport, msr);
break;
default:
dev_err(dev, "%s - unknown interrupt code, 0x%02X\n", __FUNCTION__, data[1]);
break;
}
exit:
status = usb_submit_urb(urb, GFP_ATOMIC);
if (status)
dev_err(dev, "%s - resubmit interrupt urb failed, %d\n", __FUNCTION__, status);
}
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 13:55:46 +00:00
static void ti_bulk_in_callback(struct urb *urb)
{
struct ti_port *tport = (struct ti_port *)urb->context;
struct usb_serial_port *port = tport->tp_port;
struct device *dev = &urb->dev->dev;
int status = 0;
dbg("%s", __FUNCTION__);
switch (urb->status) {
case 0:
break;
case -ECONNRESET:
case -ENOENT:
case -ESHUTDOWN:
dbg("%s - urb shutting down, %d", __FUNCTION__, urb->status);
tport->tp_tdev->td_urb_error = 1;
wake_up_interruptible(&tport->tp_write_wait);
return;
default:
dev_err(dev, "%s - nonzero urb status, %d\n", __FUNCTION__, urb->status );
tport->tp_tdev->td_urb_error = 1;
wake_up_interruptible(&tport->tp_write_wait);
}
if (urb->status == -EPIPE)
goto exit;
if (urb->status) {
dev_err(dev, "%s - stopping read!\n", __FUNCTION__);
return;
}
if (port->tty && urb->actual_length) {
usb_serial_debug_data(debug, dev, __FUNCTION__,
urb->actual_length, urb->transfer_buffer);
if (!tport->tp_is_open)
dbg("%s - port closed, dropping data", __FUNCTION__);
else
ti_recv(&urb->dev->dev, port->tty, urb->transfer_buffer,
urb->actual_length);
spin_lock(&tport->tp_lock);
tport->tp_icount.rx += urb->actual_length;
spin_unlock(&tport->tp_lock);
}
exit:
/* continue to read unless stopping */
spin_lock(&tport->tp_lock);
if (tport->tp_read_urb_state == TI_READ_URB_RUNNING) {
urb->dev = port->serial->dev;
status = usb_submit_urb(urb, GFP_ATOMIC);
} else if (tport->tp_read_urb_state == TI_READ_URB_STOPPING) {
tport->tp_read_urb_state = TI_READ_URB_STOPPED;
}
spin_unlock(&tport->tp_lock);
if (status)
dev_err(dev, "%s - resubmit read urb failed, %d\n", __FUNCTION__, status);
}
IRQ: Maintain regs pointer globally rather than passing to IRQ handlers Maintain a per-CPU global "struct pt_regs *" variable which can be used instead of passing regs around manually through all ~1800 interrupt handlers in the Linux kernel. The regs pointer is used in few places, but it potentially costs both stack space and code to pass it around. On the FRV arch, removing the regs parameter from all the genirq function results in a 20% speed up of the IRQ exit path (ie: from leaving timer_interrupt() to leaving do_IRQ()). Where appropriate, an arch may override the generic storage facility and do something different with the variable. On FRV, for instance, the address is maintained in GR28 at all times inside the kernel as part of general exception handling. Having looked over the code, it appears that the parameter may be handed down through up to twenty or so layers of functions. Consider a USB character device attached to a USB hub, attached to a USB controller that posts its interrupts through a cascaded auxiliary interrupt controller. A character device driver may want to pass regs to the sysrq handler through the input layer which adds another few layers of parameter passing. I've build this code with allyesconfig for x86_64 and i386. I've runtested the main part of the code on FRV and i386, though I can't test most of the drivers. I've also done partial conversion for powerpc and MIPS - these at least compile with minimal configurations. This will affect all archs. Mostly the changes should be relatively easy. Take do_IRQ(), store the regs pointer at the beginning, saving the old one: struct pt_regs *old_regs = set_irq_regs(regs); And put the old one back at the end: set_irq_regs(old_regs); Don't pass regs through to generic_handle_irq() or __do_IRQ(). In timer_interrupt(), this sort of change will be necessary: - update_process_times(user_mode(regs)); - profile_tick(CPU_PROFILING, regs); + update_process_times(user_mode(get_irq_regs())); + profile_tick(CPU_PROFILING); I'd like to move update_process_times()'s use of get_irq_regs() into itself, except that i386, alone of the archs, uses something other than user_mode(). Some notes on the interrupt handling in the drivers: (*) input_dev() is now gone entirely. The regs pointer is no longer stored in the input_dev struct. (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does something different depending on whether it's been supplied with a regs pointer or not. (*) Various IRQ handler function pointers have been moved to type irq_handler_t. Signed-Off-By: David Howells <dhowells@redhat.com> (cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 13:55:46 +00:00
static void ti_bulk_out_callback(struct urb *urb)
{
struct ti_port *tport = (struct ti_port *)urb->context;
struct usb_serial_port *port = tport->tp_port;
struct device *dev = &urb->dev->dev;
dbg("%s - port %d", __FUNCTION__, port->number);
tport->tp_write_urb_in_use = 0;
switch (urb->status) {
case 0:
break;
case -ECONNRESET:
case -ENOENT:
case -ESHUTDOWN:
dbg("%s - urb shutting down, %d", __FUNCTION__, urb->status);
tport->tp_tdev->td_urb_error = 1;
wake_up_interruptible(&tport->tp_write_wait);
return;
default:
dev_err(dev, "%s - nonzero urb status, %d\n", __FUNCTION__, urb->status);
tport->tp_tdev->td_urb_error = 1;
wake_up_interruptible(&tport->tp_write_wait);
}
/* send any buffered data */
ti_send(tport);
}
static void ti_recv(struct device *dev, struct tty_struct *tty,
unsigned char *data, int length)
{
int cnt;
do {
[PATCH] TTY layer buffering revamp The API and code have been through various bits of initial review by serial driver people but they definitely need to live somewhere for a while so the unconverted drivers can get knocked into shape, existing drivers that have been updated can be better tuned and bugs whacked out. This replaces the tty flip buffers with kmalloc objects in rings. In the normal situation for an IRQ driven serial port at typical speeds the behaviour is pretty much the same, two buffers end up allocated and the kernel cycles between them as before. When there are delays or at high speed we now behave far better as the buffer pool can grow a bit rather than lose characters. This also means that we can operate at higher speeds reliably. For drivers that receive characters in blocks (DMA based, USB and especially virtualisation) the layer allows a lot of driver specific code that works around the tty layer with private secondary queues to be removed. The IBM folks need this sort of layer, the smart serial port people do, the virtualisers do (because a virtualised tty typically operates at infinite speed rather than emulating 9600 baud). Finally many drivers had invalid and unsafe attempts to avoid buffer overflows by directly invoking tty methods extracted out of the innards of work queue structs. These are no longer needed and all go away. That fixes various random hangs with serial ports on overflow. The other change in here is to optimise the receive_room path that is used by some callers. It turns out that only one ldisc uses receive room except asa constant and it updates it far far less than the value is read. We thus make it a variable not a function call. I expect the code to contain bugs due to the size alone but I'll be watching and squashing them and feeding out new patches as it goes. Because the buffers now dynamically expand you should only run out of buffering when the kernel runs out of memory for real. That means a lot of the horrible hacks high performance drivers used to do just aren't needed any more. Description: tty_insert_flip_char is an old API and continues to work as before, as does tty_flip_buffer_push() [this is why many drivers dont need modification]. It does now also return the number of chars inserted There are also tty_buffer_request_room(tty, len) which asks for a buffer block of the length requested and returns the space found. This improves efficiency with hardware that knows how much to transfer. and tty_insert_flip_string_flags(tty, str, flags, len) to insert a string of characters and flags For a smart interface the usual code is len = tty_request_buffer_room(tty, amount_hardware_says); tty_insert_flip_string(tty, buffer_from_card, len); More description! At the moment tty buffers are attached directly to the tty. This is causing a lot of the problems related to tty layer locking, also problems at high speed and also with bursty data (such as occurs in virtualised environments) I'm working on ripping out the flip buffers and replacing them with a pool of dynamically allocated buffers. This allows both for old style "byte I/O" devices and also helps virtualisation and smart devices where large blocks of data suddenely materialise and need storing. So far so good. Lots of drivers reference tty->flip.*. Several of them also call directly and unsafely into function pointers it provides. This will all break. Most drivers can use tty_insert_flip_char which can be kept as an API but others need more. At the moment I've added the following interfaces, if people think more will be needed now is a good time to say int tty_buffer_request_room(tty, size) Try and ensure at least size bytes are available, returns actual room (may be zero). At the moment it just uses the flipbuf space but that will change. Repeated calls without characters being added are not cumulative. (ie if you call it with 1, 1, 1, and then 4 you'll have four characters of space. The other functions will also try and grow buffers in future but this will be a more efficient way when you know block sizes. int tty_insert_flip_char(tty, ch, flag) As before insert a character if there is room. Now returns 1 for success, 0 for failure. int tty_insert_flip_string(tty, str, len) Insert a block of non error characters. Returns the number inserted. int tty_prepare_flip_string(tty, strptr, len) Adjust the buffer to allow len characters to be added. Returns a buffer pointer in strptr and the length available. This allows for hardware that needs to use functions like insl or mencpy_fromio. Signed-off-by: Alan Cox <alan@redhat.com> Cc: Paul Fulghum <paulkf@microgate.com> Signed-off-by: Hirokazu Takata <takata@linux-m32r.org> Signed-off-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: John Hawkes <hawkes@sgi.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 04:54:13 +00:00
cnt = tty_buffer_request_room(tty, length);
if (cnt < length) {
dev_err(dev, "%s - dropping data, %d bytes lost\n", __FUNCTION__, length - cnt);
if(cnt == 0)
break;
}
[PATCH] TTY layer buffering revamp The API and code have been through various bits of initial review by serial driver people but they definitely need to live somewhere for a while so the unconverted drivers can get knocked into shape, existing drivers that have been updated can be better tuned and bugs whacked out. This replaces the tty flip buffers with kmalloc objects in rings. In the normal situation for an IRQ driven serial port at typical speeds the behaviour is pretty much the same, two buffers end up allocated and the kernel cycles between them as before. When there are delays or at high speed we now behave far better as the buffer pool can grow a bit rather than lose characters. This also means that we can operate at higher speeds reliably. For drivers that receive characters in blocks (DMA based, USB and especially virtualisation) the layer allows a lot of driver specific code that works around the tty layer with private secondary queues to be removed. The IBM folks need this sort of layer, the smart serial port people do, the virtualisers do (because a virtualised tty typically operates at infinite speed rather than emulating 9600 baud). Finally many drivers had invalid and unsafe attempts to avoid buffer overflows by directly invoking tty methods extracted out of the innards of work queue structs. These are no longer needed and all go away. That fixes various random hangs with serial ports on overflow. The other change in here is to optimise the receive_room path that is used by some callers. It turns out that only one ldisc uses receive room except asa constant and it updates it far far less than the value is read. We thus make it a variable not a function call. I expect the code to contain bugs due to the size alone but I'll be watching and squashing them and feeding out new patches as it goes. Because the buffers now dynamically expand you should only run out of buffering when the kernel runs out of memory for real. That means a lot of the horrible hacks high performance drivers used to do just aren't needed any more. Description: tty_insert_flip_char is an old API and continues to work as before, as does tty_flip_buffer_push() [this is why many drivers dont need modification]. It does now also return the number of chars inserted There are also tty_buffer_request_room(tty, len) which asks for a buffer block of the length requested and returns the space found. This improves efficiency with hardware that knows how much to transfer. and tty_insert_flip_string_flags(tty, str, flags, len) to insert a string of characters and flags For a smart interface the usual code is len = tty_request_buffer_room(tty, amount_hardware_says); tty_insert_flip_string(tty, buffer_from_card, len); More description! At the moment tty buffers are attached directly to the tty. This is causing a lot of the problems related to tty layer locking, also problems at high speed and also with bursty data (such as occurs in virtualised environments) I'm working on ripping out the flip buffers and replacing them with a pool of dynamically allocated buffers. This allows both for old style "byte I/O" devices and also helps virtualisation and smart devices where large blocks of data suddenely materialise and need storing. So far so good. Lots of drivers reference tty->flip.*. Several of them also call directly and unsafely into function pointers it provides. This will all break. Most drivers can use tty_insert_flip_char which can be kept as an API but others need more. At the moment I've added the following interfaces, if people think more will be needed now is a good time to say int tty_buffer_request_room(tty, size) Try and ensure at least size bytes are available, returns actual room (may be zero). At the moment it just uses the flipbuf space but that will change. Repeated calls without characters being added are not cumulative. (ie if you call it with 1, 1, 1, and then 4 you'll have four characters of space. The other functions will also try and grow buffers in future but this will be a more efficient way when you know block sizes. int tty_insert_flip_char(tty, ch, flag) As before insert a character if there is room. Now returns 1 for success, 0 for failure. int tty_insert_flip_string(tty, str, len) Insert a block of non error characters. Returns the number inserted. int tty_prepare_flip_string(tty, strptr, len) Adjust the buffer to allow len characters to be added. Returns a buffer pointer in strptr and the length available. This allows for hardware that needs to use functions like insl or mencpy_fromio. Signed-off-by: Alan Cox <alan@redhat.com> Cc: Paul Fulghum <paulkf@microgate.com> Signed-off-by: Hirokazu Takata <takata@linux-m32r.org> Signed-off-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: Jeff Dike <jdike@addtoit.com> Signed-off-by: John Hawkes <hawkes@sgi.com> Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com> Signed-off-by: Adrian Bunk <bunk@stusta.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-01-10 04:54:13 +00:00
tty_insert_flip_string(tty, data, cnt);
tty_flip_buffer_push(tty);
data += cnt;
length -= cnt;
} while (length > 0);
}
static void ti_send(struct ti_port *tport)
{
int count, result;
struct usb_serial_port *port = tport->tp_port;
struct tty_struct *tty = port->tty;
unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number);
spin_lock_irqsave(&tport->tp_lock, flags);
if (tport->tp_write_urb_in_use) {
spin_unlock_irqrestore(&tport->tp_lock, flags);
return;
}
count = ti_buf_get(tport->tp_write_buf,
port->write_urb->transfer_buffer,
port->bulk_out_size);
if (count == 0) {
spin_unlock_irqrestore(&tport->tp_lock, flags);
return;
}
tport->tp_write_urb_in_use = 1;
spin_unlock_irqrestore(&tport->tp_lock, flags);
usb_serial_debug_data(debug, &port->dev, __FUNCTION__, count, port->write_urb->transfer_buffer);
usb_fill_bulk_urb(port->write_urb, port->serial->dev,
usb_sndbulkpipe(port->serial->dev,
port->bulk_out_endpointAddress),
port->write_urb->transfer_buffer, count,
ti_bulk_out_callback, tport);
result = usb_submit_urb(port->write_urb, GFP_ATOMIC);
if (result) {
dev_err(&port->dev, "%s - submit write urb failed, %d\n", __FUNCTION__, result);
tport->tp_write_urb_in_use = 0;
/* TODO: reschedule ti_send */
} else {
spin_lock_irqsave(&tport->tp_lock, flags);
tport->tp_icount.tx += count;
spin_unlock_irqrestore(&tport->tp_lock, flags);
}
/* more room in the buffer for new writes, wakeup */
if (tty)
tty_wakeup(tty);
wake_up_interruptible(&tport->tp_write_wait);
}
static int ti_set_mcr(struct ti_port *tport, unsigned int mcr)
{
int status;
status = ti_write_byte(tport->tp_tdev,
tport->tp_uart_base_addr + TI_UART_OFFSET_MCR,
TI_MCR_RTS | TI_MCR_DTR | TI_MCR_LOOP, mcr);
if (!status)
tport->tp_shadow_mcr = mcr;
return status;
}
static int ti_get_lsr(struct ti_port *tport)
{
int size,status;
struct ti_device *tdev = tport->tp_tdev;
struct usb_serial_port *port = tport->tp_port;
int port_number = port->number - port->serial->minor;
struct ti_port_status *data;
dbg("%s - port %d", __FUNCTION__, port->number);
size = sizeof(struct ti_port_status);
data = kmalloc(size, GFP_KERNEL);
if (!data) {
dev_err(&port->dev, "%s - out of memory\n", __FUNCTION__);
return -ENOMEM;
}
status = ti_command_in_sync(tdev, TI_GET_PORT_STATUS,
(__u8)(TI_UART1_PORT+port_number), 0, (__u8 *)data, size);
if (status) {
dev_err(&port->dev, "%s - get port status command failed, %d\n", __FUNCTION__, status);
goto free_data;
}
dbg("%s - lsr 0x%02X", __FUNCTION__, data->bLSR);
tport->tp_lsr = data->bLSR;
free_data:
kfree(data);
return status;
}
static int ti_get_serial_info(struct ti_port *tport,
struct serial_struct __user *ret_arg)
{
struct usb_serial_port *port = tport->tp_port;
struct serial_struct ret_serial;
if (!ret_arg)
return -EFAULT;
memset(&ret_serial, 0, sizeof(ret_serial));
ret_serial.type = PORT_16550A;
ret_serial.line = port->serial->minor;
ret_serial.port = port->number - port->serial->minor;
ret_serial.flags = tport->tp_flags;
ret_serial.xmit_fifo_size = TI_WRITE_BUF_SIZE;
ret_serial.baud_base = tport->tp_tdev->td_is_3410 ? 921600 : 460800;
ret_serial.closing_wait = tport->tp_closing_wait;
if (copy_to_user(ret_arg, &ret_serial, sizeof(*ret_arg)))
return -EFAULT;
return 0;
}
static int ti_set_serial_info(struct ti_port *tport,
struct serial_struct __user *new_arg)
{
struct usb_serial_port *port = tport->tp_port;
struct serial_struct new_serial;
if (copy_from_user(&new_serial, new_arg, sizeof(new_serial)))
return -EFAULT;
tport->tp_flags = new_serial.flags & TI_SET_SERIAL_FLAGS;
if (port->tty)
port->tty->low_latency =
(tport->tp_flags & ASYNC_LOW_LATENCY) ? 1 : 0;
tport->tp_closing_wait = new_serial.closing_wait;
return 0;
}
static void ti_handle_new_msr(struct ti_port *tport, __u8 msr)
{
struct async_icount *icount;
struct tty_struct *tty;
unsigned long flags;
dbg("%s - msr 0x%02X", __FUNCTION__, msr);
if (msr & TI_MSR_DELTA_MASK) {
spin_lock_irqsave(&tport->tp_lock, flags);
icount = &tport->tp_icount;
if (msr & TI_MSR_DELTA_CTS)
icount->cts++;
if (msr & TI_MSR_DELTA_DSR)
icount->dsr++;
if (msr & TI_MSR_DELTA_CD)
icount->dcd++;
if (msr & TI_MSR_DELTA_RI)
icount->rng++;
wake_up_interruptible(&tport->tp_msr_wait);
spin_unlock_irqrestore(&tport->tp_lock, flags);
}
tport->tp_msr = msr & TI_MSR_MASK;
/* handle CTS flow control */
tty = tport->tp_port->tty;
if (tty && C_CRTSCTS(tty)) {
if (msr & TI_MSR_CTS) {
tty->hw_stopped = 0;
tty_wakeup(tty);
} else {
tty->hw_stopped = 1;
}
}
}
static void ti_drain(struct ti_port *tport, unsigned long timeout, int flush)
{
struct ti_device *tdev = tport->tp_tdev;
struct usb_serial_port *port = tport->tp_port;
wait_queue_t wait;
unsigned long flags;
dbg("%s - port %d", __FUNCTION__, port->number);
spin_lock_irqsave(&tport->tp_lock, flags);
/* wait for data to drain from the buffer */
tdev->td_urb_error = 0;
init_waitqueue_entry(&wait, current);
add_wait_queue(&tport->tp_write_wait, &wait);
for (;;) {
set_current_state(TASK_INTERRUPTIBLE);
if (ti_buf_data_avail(tport->tp_write_buf) == 0
|| timeout == 0 || signal_pending(current)
|| tdev->td_urb_error
|| !usb_get_intfdata(port->serial->interface)) /* disconnect */
break;
spin_unlock_irqrestore(&tport->tp_lock, flags);
timeout = schedule_timeout(timeout);
spin_lock_irqsave(&tport->tp_lock, flags);
}
set_current_state(TASK_RUNNING);
remove_wait_queue(&tport->tp_write_wait, &wait);
/* flush any remaining data in the buffer */
if (flush)
ti_buf_clear(tport->tp_write_buf);
spin_unlock_irqrestore(&tport->tp_lock, flags);
/* wait for data to drain from the device */
/* wait for empty tx register, plus 20 ms */
timeout += jiffies;
tport->tp_lsr &= ~TI_LSR_TX_EMPTY;
while ((long)(jiffies - timeout) < 0 && !signal_pending(current)
&& !(tport->tp_lsr&TI_LSR_TX_EMPTY) && !tdev->td_urb_error
&& usb_get_intfdata(port->serial->interface)) { /* not disconnected */
if (ti_get_lsr(tport))
break;
msleep_interruptible(20);
}
}
static void ti_stop_read(struct ti_port *tport, struct tty_struct *tty)
{
unsigned long flags;
spin_lock_irqsave(&tport->tp_lock, flags);
if (tport->tp_read_urb_state == TI_READ_URB_RUNNING)
tport->tp_read_urb_state = TI_READ_URB_STOPPING;
spin_unlock_irqrestore(&tport->tp_lock, flags);
}
static int ti_restart_read(struct ti_port *tport, struct tty_struct *tty)
{
struct urb *urb;
int status = 0;
unsigned long flags;
spin_lock_irqsave(&tport->tp_lock, flags);
if (tport->tp_read_urb_state == TI_READ_URB_STOPPED) {
urb = tport->tp_port->read_urb;
urb->complete = ti_bulk_in_callback;
urb->context = tport;
urb->dev = tport->tp_port->serial->dev;
status = usb_submit_urb(urb, GFP_KERNEL);
}
tport->tp_read_urb_state = TI_READ_URB_RUNNING;
spin_unlock_irqrestore(&tport->tp_lock, flags);
return status;
}
static int ti_command_out_sync(struct ti_device *tdev, __u8 command,
__u16 moduleid, __u16 value, __u8 *data, int size)
{
int status;
status = usb_control_msg(tdev->td_serial->dev,
usb_sndctrlpipe(tdev->td_serial->dev, 0), command,
(USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_OUT),
value, moduleid, data, size, 1000);
if (status == size)
status = 0;
if (status > 0)
status = -ECOMM;
return status;
}
static int ti_command_in_sync(struct ti_device *tdev, __u8 command,
__u16 moduleid, __u16 value, __u8 *data, int size)
{
int status;
status = usb_control_msg(tdev->td_serial->dev,
usb_rcvctrlpipe(tdev->td_serial->dev, 0), command,
(USB_TYPE_VENDOR | USB_RECIP_DEVICE | USB_DIR_IN),
value, moduleid, data, size, 1000);
if (status == size)
status = 0;
if (status > 0)
status = -ECOMM;
return status;
}
static int ti_write_byte(struct ti_device *tdev, unsigned long addr,
__u8 mask, __u8 byte)
{
int status;
unsigned int size;
struct ti_write_data_bytes *data;
struct device *dev = &tdev->td_serial->dev->dev;
dbg("%s - addr 0x%08lX, mask 0x%02X, byte 0x%02X", __FUNCTION__, addr, mask, byte);
size = sizeof(struct ti_write_data_bytes) + 2;
data = kmalloc(size, GFP_KERNEL);
if (!data) {
dev_err(dev, "%s - out of memory\n", __FUNCTION__);
return -ENOMEM;
}
data->bAddrType = TI_RW_DATA_ADDR_XDATA;
data->bDataType = TI_RW_DATA_BYTE;
data->bDataCounter = 1;
data->wBaseAddrHi = cpu_to_be16(addr>>16);
data->wBaseAddrLo = cpu_to_be16(addr);
data->bData[0] = mask;
data->bData[1] = byte;
status = ti_command_out_sync(tdev, TI_WRITE_DATA, TI_RAM_PORT, 0,
(__u8 *)data, size);
if (status < 0)
dev_err(dev, "%s - failed, %d\n", __FUNCTION__, status);
kfree(data);
return status;
}
static int ti_download_firmware(struct ti_device *tdev,
unsigned char *firmware, unsigned int firmware_size)
{
int status = 0;
int buffer_size;
int pos;
int len;
int done;
__u8 cs = 0;
__u8 *buffer;
struct usb_device *dev = tdev->td_serial->dev;
struct ti_firmware_header *header;
unsigned int pipe = usb_sndbulkpipe(dev,
tdev->td_serial->port[0]->bulk_out_endpointAddress);
buffer_size = TI_FIRMWARE_BUF_SIZE + sizeof(struct ti_firmware_header);
buffer = kmalloc(buffer_size, GFP_KERNEL);
if (!buffer) {
dev_err(&dev->dev, "%s - out of memory\n", __FUNCTION__);
return -ENOMEM;
}
memcpy(buffer, firmware, firmware_size);
memset(buffer+firmware_size, 0xff, buffer_size-firmware_size);
for(pos = sizeof(struct ti_firmware_header); pos < buffer_size; pos++)
cs = (__u8)(cs + buffer[pos]);
header = (struct ti_firmware_header *)buffer;
header->wLength = cpu_to_le16((__u16)(buffer_size - sizeof(struct ti_firmware_header)));
header->bCheckSum = cs;
dbg("%s - downloading firmware", __FUNCTION__);
for (pos = 0; pos < buffer_size; pos += done) {
len = min(buffer_size - pos, TI_DOWNLOAD_MAX_PACKET_SIZE);
status = usb_bulk_msg(dev, pipe, buffer+pos, len, &done, 1000);
if (status)
break;
}
kfree(buffer);
if (status) {
dev_err(&dev->dev, "%s - error downloading firmware, %d\n", __FUNCTION__, status);
return status;
}
dbg("%s - download successful", __FUNCTION__);
return 0;
}
/* Circular Buffer Functions */
/*
* ti_buf_alloc
*
* Allocate a circular buffer and all associated memory.
*/
static struct circ_buf *ti_buf_alloc(void)
{
struct circ_buf *cb;
cb = (struct circ_buf *)kmalloc(sizeof(struct circ_buf), GFP_KERNEL);
if (cb == NULL)
return NULL;
cb->buf = kmalloc(TI_WRITE_BUF_SIZE, GFP_KERNEL);
if (cb->buf == NULL) {
kfree(cb);
return NULL;
}
ti_buf_clear(cb);
return cb;
}
/*
* ti_buf_free
*
* Free the buffer and all associated memory.
*/
static void ti_buf_free(struct circ_buf *cb)
{
kfree(cb->buf);
kfree(cb);
}
/*
* ti_buf_clear
*
* Clear out all data in the circular buffer.
*/
static void ti_buf_clear(struct circ_buf *cb)
{
cb->head = cb->tail = 0;
}
/*
* ti_buf_data_avail
*
* Return the number of bytes of data available in the circular
* buffer.
*/
static int ti_buf_data_avail(struct circ_buf *cb)
{
return CIRC_CNT(cb->head,cb->tail,TI_WRITE_BUF_SIZE);
}
/*
* ti_buf_space_avail
*
* Return the number of bytes of space available in the circular
* buffer.
*/
static int ti_buf_space_avail(struct circ_buf *cb)
{
return CIRC_SPACE(cb->head,cb->tail,TI_WRITE_BUF_SIZE);
}
/*
* ti_buf_put
*
* Copy data data from a user buffer and put it into the circular buffer.
* Restrict to the amount of space available.
*
* Return the number of bytes copied.
*/
static int ti_buf_put(struct circ_buf *cb, const char *buf, int count)
{
int c, ret = 0;
while (1) {
c = CIRC_SPACE_TO_END(cb->head, cb->tail, TI_WRITE_BUF_SIZE);
if (count < c)
c = count;
if (c <= 0)
break;
memcpy(cb->buf + cb->head, buf, c);
cb->head = (cb->head + c) & (TI_WRITE_BUF_SIZE-1);
buf += c;
count -= c;
ret += c;
}
return ret;
}
/*
* ti_buf_get
*
* Get data from the circular buffer and copy to the given buffer.
* Restrict to the amount of data available.
*
* Return the number of bytes copied.
*/
static int ti_buf_get(struct circ_buf *cb, char *buf, int count)
{
int c, ret = 0;
while (1) {
c = CIRC_CNT_TO_END(cb->head, cb->tail, TI_WRITE_BUF_SIZE);
if (count < c)
c = count;
if (c <= 0)
break;
memcpy(buf, cb->buf + cb->tail, c);
cb->tail = (cb->tail + c) & (TI_WRITE_BUF_SIZE-1);
buf += c;
count -= c;
ret += c;
}
return ret;
}