https://github.com/torvalds/linux
Tip revision: 76e10d158efb6d4516018846f60c2ab5501900bc authored by Linus Torvalds on 20 May 2012, 22:29:13 UTC
Linux 3.4
Linux 3.4
Tip revision: 76e10d1
usbsevseg.c
/*
* USB 7 Segment Driver
*
* Copyright (C) 2008 Harrison Metzger <harrisonmetz@gmail.com>
* Based on usbled.c by Greg Kroah-Hartman (greg@kroah.com)
*
* 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, version 2.
*
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/init.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/string.h>
#include <linux/usb.h>
#define DRIVER_AUTHOR "Harrison Metzger <harrisonmetz@gmail.com>"
#define DRIVER_DESC "USB 7 Segment Driver"
#define VENDOR_ID 0x0fc5
#define PRODUCT_ID 0x1227
#define MAXLEN 8
/* table of devices that work with this driver */
static const struct usb_device_id id_table[] = {
{ USB_DEVICE(VENDOR_ID, PRODUCT_ID) },
{ },
};
MODULE_DEVICE_TABLE(usb, id_table);
/* the different text display modes the device is capable of */
static char *display_textmodes[] = {"raw", "hex", "ascii", NULL};
struct usb_sevsegdev {
struct usb_device *udev;
struct usb_interface *intf;
u8 powered;
u8 mode_msb;
u8 mode_lsb;
u8 decimals[MAXLEN];
u8 textmode;
u8 text[MAXLEN];
u16 textlength;
u8 shadow_power; /* for PM */
u8 has_interface_pm;
};
/* sysfs_streq can't replace this completely
* If the device was in hex mode, and the user wanted a 0,
* if str commands are used, we would assume the end of string
* so mem commands are used.
*/
inline size_t my_memlen(const char *buf, size_t count)
{
if (count > 0 && buf[count-1] == '\n')
return count - 1;
else
return count;
}
static void update_display_powered(struct usb_sevsegdev *mydev)
{
int rc;
if (mydev->powered && !mydev->has_interface_pm) {
rc = usb_autopm_get_interface(mydev->intf);
if (rc < 0)
return;
mydev->has_interface_pm = 1;
}
if (mydev->shadow_power != 1)
return;
rc = usb_control_msg(mydev->udev,
usb_sndctrlpipe(mydev->udev, 0),
0x12,
0x48,
(80 * 0x100) + 10, /* (power mode) */
(0x00 * 0x100) + (mydev->powered ? 1 : 0),
NULL,
0,
2000);
if (rc < 0)
dev_dbg(&mydev->udev->dev, "power retval = %d\n", rc);
if (!mydev->powered && mydev->has_interface_pm) {
usb_autopm_put_interface(mydev->intf);
mydev->has_interface_pm = 0;
}
}
static void update_display_mode(struct usb_sevsegdev *mydev)
{
int rc;
if(mydev->shadow_power != 1)
return;
rc = usb_control_msg(mydev->udev,
usb_sndctrlpipe(mydev->udev, 0),
0x12,
0x48,
(82 * 0x100) + 10, /* (set mode) */
(mydev->mode_msb * 0x100) + mydev->mode_lsb,
NULL,
0,
2000);
if (rc < 0)
dev_dbg(&mydev->udev->dev, "mode retval = %d\n", rc);
}
static void update_display_visual(struct usb_sevsegdev *mydev, gfp_t mf)
{
int rc;
int i;
unsigned char *buffer;
u8 decimals = 0;
if(mydev->shadow_power != 1)
return;
buffer = kzalloc(MAXLEN, mf);
if (!buffer) {
dev_err(&mydev->udev->dev, "out of memory\n");
return;
}
/* The device is right to left, where as you write left to right */
for (i = 0; i < mydev->textlength; i++)
buffer[i] = mydev->text[mydev->textlength-1-i];
rc = usb_control_msg(mydev->udev,
usb_sndctrlpipe(mydev->udev, 0),
0x12,
0x48,
(85 * 0x100) + 10, /* (write text) */
(0 * 0x100) + mydev->textmode, /* mode */
buffer,
mydev->textlength,
2000);
if (rc < 0)
dev_dbg(&mydev->udev->dev, "write retval = %d\n", rc);
kfree(buffer);
/* The device is right to left, where as you write left to right */
for (i = 0; i < sizeof(mydev->decimals); i++)
decimals |= mydev->decimals[i] << i;
rc = usb_control_msg(mydev->udev,
usb_sndctrlpipe(mydev->udev, 0),
0x12,
0x48,
(86 * 0x100) + 10, /* (set decimal) */
(0 * 0x100) + decimals, /* decimals */
NULL,
0,
2000);
if (rc < 0)
dev_dbg(&mydev->udev->dev, "decimal retval = %d\n", rc);
}
#define MYDEV_ATTR_SIMPLE_UNSIGNED(name, update_fcn) \
static ssize_t show_attr_##name(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct usb_interface *intf = to_usb_interface(dev); \
struct usb_sevsegdev *mydev = usb_get_intfdata(intf); \
\
return sprintf(buf, "%u\n", mydev->name); \
} \
\
static ssize_t set_attr_##name(struct device *dev, \
struct device_attribute *attr, const char *buf, size_t count) \
{ \
struct usb_interface *intf = to_usb_interface(dev); \
struct usb_sevsegdev *mydev = usb_get_intfdata(intf); \
\
mydev->name = simple_strtoul(buf, NULL, 10); \
update_fcn(mydev); \
\
return count; \
} \
static DEVICE_ATTR(name, S_IRUGO | S_IWUSR, show_attr_##name, set_attr_##name);
static ssize_t show_attr_text(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
return snprintf(buf, mydev->textlength, "%s\n", mydev->text);
}
static ssize_t set_attr_text(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
size_t end = my_memlen(buf, count);
if (end > sizeof(mydev->text))
return -EINVAL;
memset(mydev->text, 0, sizeof(mydev->text));
mydev->textlength = end;
if (end > 0)
memcpy(mydev->text, buf, end);
update_display_visual(mydev, GFP_KERNEL);
return count;
}
static DEVICE_ATTR(text, S_IRUGO | S_IWUSR, show_attr_text, set_attr_text);
static ssize_t show_attr_decimals(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
int i;
int pos;
for (i = 0; i < sizeof(mydev->decimals); i++) {
pos = sizeof(mydev->decimals) - 1 - i;
if (mydev->decimals[i] == 0)
buf[pos] = '0';
else if (mydev->decimals[i] == 1)
buf[pos] = '1';
else
buf[pos] = 'x';
}
buf[sizeof(mydev->decimals)] = '\n';
return sizeof(mydev->decimals) + 1;
}
static ssize_t set_attr_decimals(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
size_t end = my_memlen(buf, count);
int i;
if (end > sizeof(mydev->decimals))
return -EINVAL;
for (i = 0; i < end; i++)
if (buf[i] != '0' && buf[i] != '1')
return -EINVAL;
memset(mydev->decimals, 0, sizeof(mydev->decimals));
for (i = 0; i < end; i++)
if (buf[i] == '1')
mydev->decimals[end-1-i] = 1;
update_display_visual(mydev, GFP_KERNEL);
return count;
}
static DEVICE_ATTR(decimals, S_IRUGO | S_IWUSR, show_attr_decimals, set_attr_decimals);
static ssize_t show_attr_textmode(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
int i;
buf[0] = 0;
for (i = 0; display_textmodes[i]; i++) {
if (mydev->textmode == i) {
strcat(buf, " [");
strcat(buf, display_textmodes[i]);
strcat(buf, "] ");
} else {
strcat(buf, " ");
strcat(buf, display_textmodes[i]);
strcat(buf, " ");
}
}
strcat(buf, "\n");
return strlen(buf);
}
static ssize_t set_attr_textmode(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usb_sevsegdev *mydev = usb_get_intfdata(intf);
int i;
for (i = 0; display_textmodes[i]; i++) {
if (sysfs_streq(display_textmodes[i], buf)) {
mydev->textmode = i;
update_display_visual(mydev, GFP_KERNEL);
return count;
}
}
return -EINVAL;
}
static DEVICE_ATTR(textmode, S_IRUGO | S_IWUSR, show_attr_textmode, set_attr_textmode);
MYDEV_ATTR_SIMPLE_UNSIGNED(powered, update_display_powered);
MYDEV_ATTR_SIMPLE_UNSIGNED(mode_msb, update_display_mode);
MYDEV_ATTR_SIMPLE_UNSIGNED(mode_lsb, update_display_mode);
static struct attribute *dev_attrs[] = {
&dev_attr_powered.attr,
&dev_attr_text.attr,
&dev_attr_textmode.attr,
&dev_attr_decimals.attr,
&dev_attr_mode_msb.attr,
&dev_attr_mode_lsb.attr,
NULL
};
static struct attribute_group dev_attr_grp = {
.attrs = dev_attrs,
};
static int sevseg_probe(struct usb_interface *interface,
const struct usb_device_id *id)
{
struct usb_device *udev = interface_to_usbdev(interface);
struct usb_sevsegdev *mydev = NULL;
int rc = -ENOMEM;
mydev = kzalloc(sizeof(struct usb_sevsegdev), GFP_KERNEL);
if (mydev == NULL) {
dev_err(&interface->dev, "Out of memory\n");
goto error_mem;
}
mydev->udev = usb_get_dev(udev);
mydev->intf = interface;
usb_set_intfdata(interface, mydev);
/* PM */
mydev->shadow_power = 1; /* currently active */
mydev->has_interface_pm = 0; /* have not issued autopm_get */
/*set defaults */
mydev->textmode = 0x02; /* ascii mode */
mydev->mode_msb = 0x06; /* 6 characters */
mydev->mode_lsb = 0x3f; /* scanmode for 6 chars */
rc = sysfs_create_group(&interface->dev.kobj, &dev_attr_grp);
if (rc)
goto error;
dev_info(&interface->dev, "USB 7 Segment device now attached\n");
return 0;
error:
usb_set_intfdata(interface, NULL);
usb_put_dev(mydev->udev);
kfree(mydev);
error_mem:
return rc;
}
static void sevseg_disconnect(struct usb_interface *interface)
{
struct usb_sevsegdev *mydev;
mydev = usb_get_intfdata(interface);
sysfs_remove_group(&interface->dev.kobj, &dev_attr_grp);
usb_set_intfdata(interface, NULL);
usb_put_dev(mydev->udev);
kfree(mydev);
dev_info(&interface->dev, "USB 7 Segment now disconnected\n");
}
static int sevseg_suspend(struct usb_interface *intf, pm_message_t message)
{
struct usb_sevsegdev *mydev;
mydev = usb_get_intfdata(intf);
mydev->shadow_power = 0;
return 0;
}
static int sevseg_resume(struct usb_interface *intf)
{
struct usb_sevsegdev *mydev;
mydev = usb_get_intfdata(intf);
mydev->shadow_power = 1;
update_display_mode(mydev);
update_display_visual(mydev, GFP_NOIO);
return 0;
}
static int sevseg_reset_resume(struct usb_interface *intf)
{
struct usb_sevsegdev *mydev;
mydev = usb_get_intfdata(intf);
mydev->shadow_power = 1;
update_display_mode(mydev);
update_display_visual(mydev, GFP_NOIO);
return 0;
}
static struct usb_driver sevseg_driver = {
.name = "usbsevseg",
.probe = sevseg_probe,
.disconnect = sevseg_disconnect,
.suspend = sevseg_suspend,
.resume = sevseg_resume,
.reset_resume = sevseg_reset_resume,
.id_table = id_table,
.supports_autosuspend = 1,
};
module_usb_driver(sevseg_driver);
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");