|  | // SPDX-License-Identifier: GPL-2.0 | 
|  | /* -*- 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. | 
|  | */ | 
|  |  | 
|  |  | 
|  | #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; | 
|  | }; | 
|  |  | 
|  |  | 
|  | /* 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 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 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; | 
|  |  | 
|  | 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"); | 
|  | } | 
|  |  | 
|  | module_usb_driver(cytherm_driver); | 
|  |  | 
|  | MODULE_AUTHOR(DRIVER_AUTHOR); | 
|  | MODULE_DESCRIPTION(DRIVER_DESC); | 
|  | MODULE_LICENSE("GPL"); |