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/kernel.h>
18 #include <linux/errno.h>
19 #include <linux/init.h>
20 #include <linux/module.h>
21 #include <linux/usb.h>
23 #define DRIVER_VERSION "v1.0"
24 #define DRIVER_AUTHOR "Erik Rigtorp"
25 #define DRIVER_DESC "Cypress USB Thermometer driver"
27 #define USB_SKEL_VENDOR_ID 0x04b4
28 #define USB_SKEL_PRODUCT_ID 0x0002
30 static struct usb_device_id id_table [] = {
31 { USB_DEVICE(USB_SKEL_VENDOR_ID, USB_SKEL_PRODUCT_ID) },
34 MODULE_DEVICE_TABLE (usb, id_table);
36 /* Structure to hold all of our device specific stuff */
38 struct usb_device *udev; /* save off the usb device pointer */
39 struct usb_interface *interface; /* the interface for this device */
44 /* local function prototypes */
45 static int cytherm_probe(struct usb_interface *interface,
46 const struct usb_device_id *id);
47 static void cytherm_disconnect(struct usb_interface *interface);
50 /* usb specific object needed to register this driver with the usb subsystem */
51 static struct usb_driver cytherm_driver = {
53 .probe = cytherm_probe,
54 .disconnect = cytherm_disconnect,
59 /* They all operate on one byte at a time */
61 #define READ_ROM 0x01 /* Reads form ROM, value = address */
62 #define READ_RAM 0x02 /* Reads form RAM, value = address */
63 #define WRITE_RAM 0x03 /* Write to RAM, value = address, index = data */
64 #define READ_PORT 0x04 /* Reads from port, value = address */
65 #define WRITE_PORT 0x05 /* Write to port, value = address, index = data */
68 /* Send a vendor command to device */
69 static int vendor_command(struct usb_device *dev, unsigned char request,
70 unsigned char value, unsigned char index,
73 return usb_control_msg(dev, usb_rcvctrlpipe(dev, 0),
75 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_OTHER,
78 USB_CTRL_GET_TIMEOUT);
83 #define BRIGHTNESS 0x2c /* RAM location for brightness value */
84 #define BRIGHTNESS_SEM 0x2b /* RAM location for brightness semaphore */
86 static ssize_t show_brightness(struct device *dev, struct device_attribute *attr, char *buf)
88 struct usb_interface *intf = to_usb_interface(dev);
89 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
91 return sprintf(buf, "%i", cytherm->brightness);
94 static ssize_t set_brightness(struct device *dev, struct device_attribute *attr, const char *buf,
97 struct usb_interface *intf = to_usb_interface(dev);
98 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
100 unsigned char *buffer;
103 buffer = kmalloc(8, GFP_KERNEL);
105 dev_err(&cytherm->udev->dev, "out of memory\n");
109 cytherm->brightness = simple_strtoul(buf, NULL, 10);
111 if (cytherm->brightness > 0xFF)
112 cytherm->brightness = 0xFF;
113 else if (cytherm->brightness < 0)
114 cytherm->brightness = 0;
117 retval = vendor_command(cytherm->udev, WRITE_RAM, BRIGHTNESS,
118 cytherm->brightness, buffer, 8);
120 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
121 /* Inform µC that we have changed the brightness setting */
122 retval = vendor_command(cytherm->udev, WRITE_RAM, BRIGHTNESS_SEM,
125 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
132 static DEVICE_ATTR(brightness, S_IRUGO | S_IWUSR | S_IWGRP,
133 show_brightness, set_brightness);
136 #define TEMP 0x33 /* RAM location for temperature */
137 #define SIGN 0x34 /* RAM location for temperature sign */
139 static ssize_t show_temp(struct device *dev, struct device_attribute *attr, char *buf)
142 struct usb_interface *intf = to_usb_interface(dev);
143 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
146 unsigned char *buffer;
150 buffer = kmalloc(8, GFP_KERNEL);
152 dev_err(&cytherm->udev->dev, "out of memory\n");
156 /* read temperature */
157 retval = vendor_command(cytherm->udev, READ_RAM, TEMP, 0, buffer, 8);
159 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
163 retval = vendor_command(cytherm->udev, READ_RAM, SIGN, 0, buffer, 8);
165 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
170 return sprintf(buf, "%c%i.%i", sign ? '-' : '+', temp >> 1,
171 5*(temp - ((temp >> 1) << 1)));
175 static ssize_t set_temp(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
180 static DEVICE_ATTR(temp, S_IRUGO, show_temp, set_temp);
185 static ssize_t show_button(struct device *dev, struct device_attribute *attr, char *buf)
188 struct usb_interface *intf = to_usb_interface(dev);
189 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
192 unsigned char *buffer;
194 buffer = kmalloc(8, GFP_KERNEL);
196 dev_err(&cytherm->udev->dev, "out of memory\n");
201 retval = vendor_command(cytherm->udev, READ_RAM, BUTTON, 0, buffer, 8);
203 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
210 return sprintf(buf, "1");
212 return sprintf(buf, "0");
216 static ssize_t set_button(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
221 static DEVICE_ATTR(button, S_IRUGO, show_button, set_button);
224 static ssize_t show_port0(struct device *dev, struct device_attribute *attr, char *buf)
226 struct usb_interface *intf = to_usb_interface(dev);
227 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
230 unsigned char *buffer;
232 buffer = kmalloc(8, GFP_KERNEL);
234 dev_err(&cytherm->udev->dev, "out of memory\n");
238 retval = vendor_command(cytherm->udev, READ_PORT, 0, 0, buffer, 8);
240 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
246 return sprintf(buf, "%d", retval);
250 static ssize_t set_port0(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
252 struct usb_interface *intf = to_usb_interface(dev);
253 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
255 unsigned char *buffer;
259 buffer = kmalloc(8, GFP_KERNEL);
261 dev_err(&cytherm->udev->dev, "out of memory\n");
265 tmp = simple_strtoul(buf, NULL, 10);
272 retval = vendor_command(cytherm->udev, WRITE_PORT, 0,
275 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
282 static DEVICE_ATTR(port0, S_IRUGO | S_IWUSR | S_IWGRP, show_port0, set_port0);
284 static ssize_t show_port1(struct device *dev, struct device_attribute *attr, char *buf)
286 struct usb_interface *intf = to_usb_interface(dev);
287 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
290 unsigned char *buffer;
292 buffer = kmalloc(8, GFP_KERNEL);
294 dev_err(&cytherm->udev->dev, "out of memory\n");
298 retval = vendor_command(cytherm->udev, READ_PORT, 1, 0, buffer, 8);
300 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
306 return sprintf(buf, "%d", retval);
310 static ssize_t set_port1(struct device *dev, struct device_attribute *attr, const char *buf, size_t count)
312 struct usb_interface *intf = to_usb_interface(dev);
313 struct usb_cytherm *cytherm = usb_get_intfdata(intf);
315 unsigned char *buffer;
319 buffer = kmalloc(8, GFP_KERNEL);
321 dev_err(&cytherm->udev->dev, "out of memory\n");
325 tmp = simple_strtoul(buf, NULL, 10);
332 retval = vendor_command(cytherm->udev, WRITE_PORT, 1,
335 dev_dbg(&cytherm->udev->dev, "retval = %d\n", retval);
342 static DEVICE_ATTR(port1, S_IRUGO | S_IWUSR | S_IWGRP, show_port1, set_port1);
346 static int cytherm_probe(struct usb_interface *interface,
347 const struct usb_device_id *id)
349 struct usb_device *udev = interface_to_usbdev(interface);
350 struct usb_cytherm *dev = NULL;
351 int retval = -ENOMEM;
353 dev = kzalloc (sizeof(struct usb_cytherm), GFP_KERNEL);
355 dev_err (&interface->dev, "Out of memory\n");
359 dev->udev = usb_get_dev(udev);
361 usb_set_intfdata (interface, dev);
363 dev->brightness = 0xFF;
365 retval = device_create_file(&interface->dev, &dev_attr_brightness);
368 retval = device_create_file(&interface->dev, &dev_attr_temp);
371 retval = device_create_file(&interface->dev, &dev_attr_button);
374 retval = device_create_file(&interface->dev, &dev_attr_port0);
377 retval = device_create_file(&interface->dev, &dev_attr_port1);
381 dev_info (&interface->dev,
382 "Cypress thermometer device now attached\n");
385 device_remove_file(&interface->dev, &dev_attr_brightness);
386 device_remove_file(&interface->dev, &dev_attr_temp);
387 device_remove_file(&interface->dev, &dev_attr_button);
388 device_remove_file(&interface->dev, &dev_attr_port0);
389 device_remove_file(&interface->dev, &dev_attr_port1);
390 usb_set_intfdata (interface, NULL);
391 usb_put_dev(dev->udev);
397 static void cytherm_disconnect(struct usb_interface *interface)
399 struct usb_cytherm *dev;
401 dev = usb_get_intfdata (interface);
403 device_remove_file(&interface->dev, &dev_attr_brightness);
404 device_remove_file(&interface->dev, &dev_attr_temp);
405 device_remove_file(&interface->dev, &dev_attr_button);
406 device_remove_file(&interface->dev, &dev_attr_port0);
407 device_remove_file(&interface->dev, &dev_attr_port1);
409 /* first remove the files, then NULL the pointer */
410 usb_set_intfdata (interface, NULL);
412 usb_put_dev(dev->udev);
416 dev_info(&interface->dev, "Cypress thermometer now disconnected\n");
420 static int __init usb_cytherm_init(void)
424 result = usb_register(&cytherm_driver);
426 printk(KERN_ERR KBUILD_MODNAME ": usb_register failed! "
427 "Error number: %d\n", result);
431 printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":"
436 static void __exit usb_cytherm_exit(void)
438 usb_deregister(&cytherm_driver);
442 module_init (usb_cytherm_init);
443 module_exit (usb_cytherm_exit);
445 MODULE_AUTHOR(DRIVER_AUTHOR);
446 MODULE_DESCRIPTION(DRIVER_DESC);
447 MODULE_LICENSE("GPL");