2 * Cypress USB Thermometer driver
4 * Copyright (c) 2004 Erik Rigtorp <erkki@linux.nu> <erik@rigtorp.com>
6 * This driver works with Elektor magazine USB Interface as published in
7 * issue #291. It should also work with the original starter kit/demo board
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License as
12 * published by the Free Software Foundation, version 2.
17 #include <linux/config.h>
18 #include <linux/kernel.h>
19 #include <linux/errno.h>
20 #include <linux/init.h>
21 #include <linux/module.h>
22 #include <linux/usb.h>
24 #define DRIVER_VERSION "v1.0"
25 #define DRIVER_AUTHOR "Erik Rigtorp"
26 #define DRIVER_DESC "Cypress USB Thermometer driver"
28 #define USB_SKEL_VENDOR_ID 0x04b4
29 #define USB_SKEL_PRODUCT_ID 0x0002
31 static struct usb_device_id id_table [] = {
32 { USB_DEVICE(USB_SKEL_VENDOR_ID, USB_SKEL_PRODUCT_ID) },
35 MODULE_DEVICE_TABLE (usb, id_table);
37 /* Structure to hold all of our device specific stuff */
39 struct usb_device *udev; /* save off the usb device pointer */
40 struct usb_interface *interface; /* the interface for this device */
45 /* local function prototypes */
46 static int cytherm_probe(struct usb_interface *interface,
47 const struct usb_device_id *id);
48 static void cytherm_disconnect(struct usb_interface *interface);
51 /* usb specific object needed to register this driver with the usb subsystem */
52 static struct usb_driver cytherm_driver = {
55 .probe = cytherm_probe,
56 .disconnect = cytherm_disconnect,
61 /* They all operate on one byte at a time */
63 #define READ_ROM 0x01 /* Reads form ROM, value = address */
64 #define READ_RAM 0x02 /* Reads form RAM, value = address */
65 #define WRITE_RAM 0x03 /* Write to RAM, value = address, index = data */
66 #define READ_PORT 0x04 /* Reads from port, value = address */
67 #define WRITE_PORT 0x05 /* Write to port, value = address, index = data */
70 /* Send a vendor command to device */
71 static int vendor_command(struct usb_device *dev, unsigned char request,
72 unsigned char value, unsigned char index,
75 return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
77 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_OTHER,
80 USB_CTRL_GET_TIMEOUT);
85 #define BRIGHTNESS 0x2c /* RAM location for brightness value */
86 #define BRIGHTNESS_SEM 0x2b /* RAM location for brightness semaphore */
88 static ssize_t show_brightness(struct device *dev, struct device_attribute *attr, char *buf)
90 struct usb_interface *intf = to_usb_interface(dev);
91 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
93 return sprintf(buf, "%i", cytherm->brightness);
96 static ssize_t set_brightness(struct device *dev, struct device_attribute *attr, const char *buf,
99 struct usb_interface *intf = to_usb_interface(dev);
100 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
102 unsigned char *buffer;
105 buffer = kmalloc(8, GFP_KERNEL);
107 dev_err(&cytherm->udev->dev, "out of memory\n");
111 cytherm->brightness = simple_strtoul(buf, NULL, 10);
113 if (cytherm->brightness > 0xFF)
114 cytherm->brightness = 0xFF;
115 else if (cytherm->brightness < 0)
116 cytherm->brightness = 0;
119 retval = vendor_command(cytherm->udev, WRITE_RAM, BRIGHTNESS,
120 cytherm->brightness, buffer, 8);
122 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
123 /* Inform µC that we have changed the brightness setting */
124 retval = vendor_command(cytherm->udev, WRITE_RAM, BRIGHTNESS_SEM,
127 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
134 static DEVICE_ATTR(brightness, S_IRUGO | S_IWUSR | S_IWGRP,
135 show_brightness, set_brightness);
138 #define TEMP 0x33 /* RAM location for temperature */
139 #define SIGN 0x34 /* RAM location for temperature sign */
141 static ssize_t show_temp(struct device *dev, struct device_attribute *attr, char *buf)
144 struct usb_interface *intf = to_usb_interface(dev);
145 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
148 unsigned char *buffer;
152 buffer = kmalloc(8, GFP_KERNEL);
154 dev_err(&cytherm->udev->dev, "out of memory\n");
158 /* read temperature */
159 retval = vendor_command(cytherm->udev, READ_RAM, TEMP, 0, buffer, 8);
161 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
165 retval = vendor_command(cytherm->udev, READ_RAM, SIGN, 0, buffer, 8);
167 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
172 return sprintf(buf, "%c%i.%i", sign ? '-' : '+', temp >> 1,
173 5*(temp - ((temp >> 1) << 1)));
177 static ssize_t set_temp(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
182 static DEVICE_ATTR(temp, S_IRUGO, show_temp, set_temp);
187 static ssize_t show_button(struct device *dev, struct device_attribute *attr, char *buf)
190 struct usb_interface *intf = to_usb_interface(dev);
191 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
194 unsigned char *buffer;
196 buffer = kmalloc(8, GFP_KERNEL);
198 dev_err(&cytherm->udev->dev, "out of memory\n");
203 retval = vendor_command(cytherm->udev, READ_RAM, BUTTON, 0, buffer, 8);
205 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
212 return sprintf(buf, "1");
214 return sprintf(buf, "0");
218 static ssize_t set_button(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
223 static DEVICE_ATTR(button, S_IRUGO, show_button, set_button);
226 static ssize_t show_port0(struct device *dev, struct device_attribute *attr, char *buf)
228 struct usb_interface *intf = to_usb_interface(dev);
229 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
232 unsigned char *buffer;
234 buffer = kmalloc(8, GFP_KERNEL);
236 dev_err(&cytherm->udev->dev, "out of memory\n");
240 retval = vendor_command(cytherm->udev, READ_PORT, 0, 0, buffer, 8);
242 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
248 return sprintf(buf, "%d", retval);
252 static ssize_t set_port0(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
254 struct usb_interface *intf = to_usb_interface(dev);
255 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
257 unsigned char *buffer;
261 buffer = kmalloc(8, GFP_KERNEL);
263 dev_err(&cytherm->udev->dev, "out of memory\n");
267 tmp = simple_strtoul(buf, NULL, 10);
274 retval = vendor_command(cytherm->udev, WRITE_PORT, 0,
277 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
284 static DEVICE_ATTR(port0, S_IRUGO | S_IWUSR | S_IWGRP, show_port0, set_port0);
286 static ssize_t show_port1(struct device *dev, struct device_attribute *attr, char *buf)
288 struct usb_interface *intf = to_usb_interface(dev);
289 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
292 unsigned char *buffer;
294 buffer = kmalloc(8, GFP_KERNEL);
296 dev_err(&cytherm->udev->dev, "out of memory\n");
300 retval = vendor_command(cytherm->udev, READ_PORT, 1, 0, buffer, 8);
302 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
308 return sprintf(buf, "%d", retval);
312 static ssize_t set_port1(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
314 struct usb_interface *intf = to_usb_interface(dev);
315 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
317 unsigned char *buffer;
321 buffer = kmalloc(8, GFP_KERNEL);
323 dev_err(&cytherm->udev->dev, "out of memory\n");
327 tmp = simple_strtoul(buf, NULL, 10);
334 retval = vendor_command(cytherm->udev, WRITE_PORT, 1,
337 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
344 static DEVICE_ATTR(port1, S_IRUGO | S_IWUSR | S_IWGRP, show_port1, set_port1);
348 static int cytherm_probe(struct usb_interface *interface,
349 const struct usb_device_id *id)
351 struct usb_device *udev = interface_to_usbdev(interface);
352 struct usb_cytherm *dev = NULL;
353 int retval = -ENOMEM;
355 dev = kmalloc (sizeof(struct usb_cytherm), GFP_KERNEL);
357 dev_err (&interface->dev, "Out of memory\n");
360 memset (dev, 0x00, sizeof (*dev));
362 dev->udev = usb_get_dev(udev);
364 usb_set_intfdata (interface, dev);
366 dev->brightness = 0xFF;
368 device_create_file(&interface->dev, &dev_attr_brightness);
369 device_create_file(&interface->dev, &dev_attr_temp);
370 device_create_file(&interface->dev, &dev_attr_button);
371 device_create_file(&interface->dev, &dev_attr_port0);
372 device_create_file(&interface->dev, &dev_attr_port1);
374 dev_info (&interface->dev,
375 "Cypress thermometer device now attached\n");
383 static void cytherm_disconnect(struct usb_interface *interface)
385 struct usb_cytherm *dev;
387 dev = usb_get_intfdata (interface);
388 usb_set_intfdata (interface, NULL);
390 device_remove_file(&interface->dev, &dev_attr_brightness);
391 device_remove_file(&interface->dev, &dev_attr_temp);
392 device_remove_file(&interface->dev, &dev_attr_button);
393 device_remove_file(&interface->dev, &dev_attr_port0);
394 device_remove_file(&interface->dev, &dev_attr_port1);
396 usb_put_dev(dev->udev);
400 dev_info(&interface->dev, "Cypress thermometer now disconnected\n");
404 static int __init usb_cytherm_init(void)
408 result = usb_register(&cytherm_driver);
411 err("usb_register failed. Error number %d", result);
415 info(DRIVER_VERSION ":" DRIVER_DESC);
419 static void __exit usb_cytherm_exit(void)
421 usb_deregister(&cytherm_driver);
425 module_init (usb_cytherm_init);
426 module_exit (usb_cytherm_exit);
428 MODULE_AUTHOR(DRIVER_AUTHOR);
429 MODULE_DESCRIPTION(DRIVER_DESC);
430 MODULE_LICENSE("GPL");