// SPDX-License-Identifier: GPL-2.0 /* -*- linux-c -*- * Cypress USB Thermometer driver * * Copyright (c) 2004 Erik Rigtorp * * 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 #include #include #include #include #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 = NULL; 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");