/* -*- linux-c -*- * Cypress USB Thermometer driver * * Copyright (c) 2004 Erik Rigtorp <erkki@linux.nu> <erik@rigtorp.com> * * 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. * * 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/usb.h> #define DRIVER_VERSION "v1.0" #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; }; /* local function prototypes */ static int cytherm_probe(struct usb_interface *interface, const struct usb_device_id *id); static void cytherm_disconnect(struct usb_interface *interface); /* 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, }; /* 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 show_brightness(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 set_brightness(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) { dev_err(&cytherm->udev->dev, "out of memory\n"); 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(brightness, S_IRUGO | S_IWUSR | S_IWGRP, show_brightness, set_brightness); #define TEMP 0x33 /* RAM location for temperature */ #define SIGN 0x34 /* RAM location for temperature sign */ static ssize_t show_temp(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) { dev_err(&cytherm->udev->dev, "out of memory\n"); 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 ssize_t set_temp(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { return count; } static DEVICE_ATTR(temp, S_IRUGO, show_temp, set_temp); #define BUTTON 0x7a static ssize_t show_button(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) { dev_err(&cytherm->udev->dev, "out of memory\n"); 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 ssize_t set_button(struct device *dev, struct device_attribute *attr, const char *buf, size_t count) { return count; } static DEVICE_ATTR(button, S_IRUGO, show_button, set_button); static ssize_t show_port0(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) { dev_err(&cytherm->udev->dev, "out of memory\n"); 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 set_port0(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) { dev_err(&cytherm->udev->dev, "out of memory\n"); 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(port0, S_IRUGO | S_IWUSR | S_IWGRP, show_port0, set_port0); static ssize_t show_port1(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) { dev_err(&cytherm->udev->dev, "out of memory\n"); 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 set_port1(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) { dev_err(&cytherm->udev->dev, "out of memory\n"); 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(port1, S_IRUGO | S_IWUSR | S_IWGRP, show_port1, set_port1); 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 = NULL; int retval = -ENOMEM; dev = kzalloc (sizeof(struct usb_cytherm), GFP_KERNEL); if (dev == NULL) { dev_err (&interface->dev, "Out of memory\n"); goto error_mem; } dev->udev = usb_get_dev(udev); usb_set_intfdata (interface, dev); dev->brightness = 0xFF; retval = device_create_file(&interface->dev, &dev_attr_brightness); if (retval) goto error; retval = device_create_file(&interface->dev, &dev_attr_temp); if (retval) goto error; retval = device_create_file(&interface->dev, &dev_attr_button); if (retval) goto error; retval = device_create_file(&interface->dev, &dev_attr_port0); if (retval) goto error; retval = device_create_file(&interface->dev, &dev_attr_port1); if (retval) goto error; dev_info (&interface->dev, "Cypress thermometer device now attached\n"); return 0; error: device_remove_file(&interface->dev, &dev_attr_brightness); device_remove_file(&interface->dev, &dev_attr_temp); device_remove_file(&interface->dev, &dev_attr_button); device_remove_file(&interface->dev, &dev_attr_port0); device_remove_file(&interface->dev, &dev_attr_port1); usb_set_intfdata (interface, NULL); usb_put_dev(dev->udev); kfree(dev); error_mem: return retval; } static void cytherm_disconnect(struct usb_interface *interface) { struct usb_cytherm *dev; dev = usb_get_intfdata (interface); device_remove_file(&interface->dev, &dev_attr_brightness); device_remove_file(&interface->dev, &dev_attr_temp); device_remove_file(&interface->dev, &dev_attr_button); device_remove_file(&interface->dev, &dev_attr_port0); device_remove_file(&interface->dev, &dev_attr_port1); /* 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"); } static int __init usb_cytherm_init(void) { int result; result = usb_register(&cytherm_driver); if (result) { printk(KERN_ERR KBUILD_MODNAME ": usb_register failed! " "Error number: %d\n", result); return result; } printk(KERN_INFO KBUILD_MODNAME ": " DRIVER_VERSION ":" DRIVER_DESC "\n"); return 0; } static void __exit usb_cytherm_exit(void) { usb_deregister(&cytherm_driver); } module_init (usb_cytherm_init); module_exit (usb_cytherm_exit); MODULE_AUTHOR(DRIVER_AUTHOR); MODULE_DESCRIPTION(DRIVER_DESC); MODULE_LICENSE("GPL");