// SPDX-License-Identifier: GPL-2.0
/* -*- linux-c -*-
* Cypress USB Thermometer driver
*
* Copyright (c) 2004 Erik Rigtorp <[email protected]> <[email protected]>
*
* This driver works with Elektor magazine USB Interface as published in
* issue #291. It should also work with the original starter kit/demo board
* from Cypress.
*/
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/slab.h>
#include <linux/module.h>
#include <linux/usb.h>
#define DRIVER_AUTHOR "Erik Rigtorp"
#define DRIVER_DESC "Cypress USB Thermometer driver"
#define USB_SKEL_VENDOR_ID 0x04b4
#define USB_SKEL_PRODUCT_ID 0x0002
static const struct usb_device_id id_table[] = {
{ USB_DEVICE(USB_SKEL_VENDOR_ID, USB_SKEL_PRODUCT_ID) },
{ }
};
MODULE_DEVICE_TABLE (usb, id_table);
/* Structure to hold all of our device specific stuff */
struct usb_cytherm {
struct usb_device *udev; /* save off the usb device pointer */
struct usb_interface *interface; /* the interface for this device */
int brightness;
};
/* Vendor requests */
/* They all operate on one byte at a time */
#define PING 0x00
#define READ_ROM 0x01 /* Reads form ROM, value = address */
#define READ_RAM 0x02 /* Reads form RAM, value = address */
#define WRITE_RAM 0x03 /* Write to RAM, value = address, index = data */
#define READ_PORT 0x04 /* Reads from port, value = address */
#define WRITE_PORT 0x05 /* Write to port, value = address, index = data */
/* Send a vendor command to device */
static int vendor_command(struct usb_device *dev, unsigned char request,
unsigned char value, unsigned char index,
void *buf, int size)
{
return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
request,
USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_OTHER,
value,
index, buf, size,
USB_CTRL_GET_TIMEOUT);
}
#define BRIGHTNESS 0x2c /* RAM location for brightness value */
#define BRIGHTNESS_SEM 0x2b /* RAM location for brightness semaphore */
static ssize_t brightness_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usb_cytherm *cytherm = usb_get_intfdata(intf);
return sprintf(buf, "%i", cytherm->brightness);
}
static ssize_t brightness_store(struct device *dev, struct device_attribute *attr, const char *buf,
size_t count)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usb_cytherm *cytherm = usb_get_intfdata(intf);
unsigned char *buffer;
int retval;
buffer = kmalloc(8, GFP_KERNEL);
if (!buffer)
return 0;
cytherm->brightness = simple_strtoul(buf, NULL, 10);
if (cytherm->brightness > 0xFF)
cytherm->brightness = 0xFF;
else if (cytherm->brightness < 0)
cytherm->brightness = 0;
/* Set brightness */
retval = vendor_command(cytherm->udev, WRITE_RAM, BRIGHTNESS,
cytherm->brightness, buffer, 8);
if (retval)
dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
/* Inform µC that we have changed the brightness setting */
retval = vendor_command(cytherm->udev, WRITE_RAM, BRIGHTNESS_SEM,
0x01, buffer, 8);
if (retval)
dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
kfree(buffer);
return count;
}
static DEVICE_ATTR_RW(brightness);
#define TEMP 0x33 /* RAM location for temperature */
#define SIGN 0x34 /* RAM location for temperature sign */
static ssize_t temp_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usb_cytherm *cytherm = usb_get_intfdata(intf);
int retval;
unsigned char *buffer;
int temp, sign;
buffer = kmalloc(8, GFP_KERNEL);
if (!buffer)
return 0;
/* read temperature */
retval = vendor_command(cytherm->udev, READ_RAM, TEMP, 0, buffer, 8);
if (retval)
dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
temp = buffer[1];
/* read sign */
retval = vendor_command(cytherm->udev, READ_RAM, SIGN, 0, buffer, 8);
if (retval)
dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
sign = buffer[1];
kfree(buffer);
return sprintf(buf, "%c%i.%i", sign ? '-' : '+', temp >> 1,
5*(temp - ((temp >> 1) << 1)));
}
static DEVICE_ATTR_RO(temp);
#define BUTTON 0x7a
static ssize_t button_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usb_cytherm *cytherm = usb_get_intfdata(intf);
int retval;
unsigned char *buffer;
buffer = kmalloc(8, GFP_KERNEL);
if (!buffer)
return 0;
/* check button */
retval = vendor_command(cytherm->udev, READ_RAM, BUTTON, 0, buffer, 8);
if (retval)
dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
retval = buffer[1];
kfree(buffer);
if (retval)
return sprintf(buf, "1");
else
return sprintf(buf, "0");
}
static DEVICE_ATTR_RO(button);
static ssize_t port0_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usb_cytherm *cytherm = usb_get_intfdata(intf);
int retval;
unsigned char *buffer;
buffer = kmalloc(8, GFP_KERNEL);
if (!buffer)
return 0;
retval = vendor_command(cytherm->udev, READ_PORT, 0, 0, buffer, 8);
if (retval)
dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
retval = buffer[1];
kfree(buffer);
return sprintf(buf, "%d", retval);
}
static ssize_t port0_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usb_cytherm *cytherm = usb_get_intfdata(intf);
unsigned char *buffer;
int retval;
int tmp;
buffer = kmalloc(8, GFP_KERNEL);
if (!buffer)
return 0;
tmp = simple_strtoul(buf, NULL, 10);
if (tmp > 0xFF)
tmp = 0xFF;
else if (tmp < 0)
tmp = 0;
retval = vendor_command(cytherm->udev, WRITE_PORT, 0,
tmp, buffer, 8);
if (retval)
dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
kfree(buffer);
return count;
}
static DEVICE_ATTR_RW(port0);
static ssize_t port1_show(struct device *dev, struct device_attribute *attr, char *buf)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usb_cytherm *cytherm = usb_get_intfdata(intf);
int retval;
unsigned char *buffer;
buffer = kmalloc(8, GFP_KERNEL);
if (!buffer)
return 0;
retval = vendor_command(cytherm->udev, READ_PORT, 1, 0, buffer, 8);
if (retval)
dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
retval = buffer[1];
kfree(buffer);
return sprintf(buf, "%d", retval);
}
static ssize_t port1_store(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
{
struct usb_interface *intf = to_usb_interface(dev);
struct usb_cytherm *cytherm = usb_get_intfdata(intf);
unsigned char *buffer;
int retval;
int tmp;
buffer = kmalloc(8, GFP_KERNEL);
if (!buffer)
return 0;
tmp = simple_strtoul(buf, NULL, 10);
if (tmp > 0xFF)
tmp = 0xFF;
else if (tmp < 0)
tmp = 0;
retval = vendor_command(cytherm->udev, WRITE_PORT, 1,
tmp, buffer, 8);
if (retval)
dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
kfree(buffer);
return count;
}
static DEVICE_ATTR_RW(port1);
static struct attribute *cytherm_attrs[] = {
&dev_attr_brightness.attr,
&dev_attr_temp.attr,
&dev_attr_button.attr,
&dev_attr_port0.attr,
&dev_attr_port1.attr,
NULL,
};
ATTRIBUTE_GROUPS(cytherm);
static int cytherm_probe(struct usb_interface *interface,
const struct usb_device_id *id)
{
struct usb_device *udev = interface_to_usbdev(interface);
struct usb_cytherm *dev;
int retval = -ENOMEM;
dev = kzalloc(sizeof(struct usb_cytherm), GFP_KERNEL);
if (!dev)
goto error_mem;
dev->udev = usb_get_dev(udev);
usb_set_intfdata(interface, dev);
dev->brightness = 0xFF;
dev_info(&interface->dev,
"Cypress thermometer device now attached\n");
return 0;
error_mem:
return retval;
}
static void cytherm_disconnect(struct usb_interface *interface)
{
struct usb_cytherm *dev;
dev = usb_get_intfdata(interface);
/* first remove the files, then NULL the pointer */
usb_set_intfdata(interface, NULL);
usb_put_dev(dev->udev);
kfree(dev);
dev_info(&interface->dev, "Cypress thermometer now disconnected\n");
}
/* usb specific object needed to register this driver with the usb subsystem */
static struct usb_driver cytherm_driver = {
.name = "cytherm",
.probe = cytherm_probe,
.disconnect = cytherm_disconnect,
.id_table = id_table,
.dev_groups = cytherm_groups,
};
module_usb_driver(cytherm_driver);
MODULE_AUTHOR(DRIVER_AUTHOR);
MODULE_DESCRIPTION(DRIVER_DESC);
MODULE_LICENSE("GPL");
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