1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * cypress_cy7c63.c 4 * 5 * Copyright (c) 2006-2007 Oliver Bock (bock@tfh-berlin.de) 6 * 7 * This driver is based on the Cypress USB Driver by Marcus Maul 8 * (cyport) and the 2.0 version of Greg Kroah-Hartman's 9 * USB Skeleton driver. 10 * 11 * This is a generic driver for the Cypress CY7C63xxx family. 12 * For the time being it enables you to read from and write to 13 * the single I/O ports of the device. 14 * 15 * Supported vendors: AK Modul-Bus Computer GmbH 16 * (Firmware "Port-Chip") 17 * 18 * Supported devices: CY7C63001A-PC 19 * CY7C63001C-PXC 20 * CY7C63001C-SXC 21 * 22 * Supported functions: Read/Write Ports 23 * 24 * 25 * For up-to-date information please visit: 26 * http://www.obock.de/kernel/cypress 27 */ 28 29 #include <linux/module.h> 30 #include <linux/kernel.h> 31 #include <linux/slab.h> 32 #include <linux/usb.h> 33 34 #define DRIVER_AUTHOR "Oliver Bock (bock@tfh-berlin.de)" 35 #define DRIVER_DESC "Cypress CY7C63xxx USB driver" 36 37 #define CYPRESS_VENDOR_ID 0xa2c 38 #define CYPRESS_PRODUCT_ID 0x8 39 40 #define CYPRESS_READ_PORT 0x4 41 #define CYPRESS_WRITE_PORT 0x5 42 43 #define CYPRESS_READ_RAM 0x2 44 #define CYPRESS_WRITE_RAM 0x3 45 #define CYPRESS_READ_ROM 0x1 46 47 #define CYPRESS_READ_PORT_ID0 0 48 #define CYPRESS_WRITE_PORT_ID0 0 49 #define CYPRESS_READ_PORT_ID1 0x2 50 #define CYPRESS_WRITE_PORT_ID1 1 51 52 #define CYPRESS_MAX_REQSIZE 8 53 54 55 /* table of devices that work with this driver */ 56 static const struct usb_device_id cypress_table[] = { 57 { USB_DEVICE(CYPRESS_VENDOR_ID, CYPRESS_PRODUCT_ID) }, 58 { } 59 }; 60 MODULE_DEVICE_TABLE(usb, cypress_table); 61 62 /* structure to hold all of our device specific stuff */ 63 struct cypress { 64 struct usb_device * udev; 65 unsigned char port[2]; 66 }; 67 68 /* used to send usb control messages to device */ 69 static int vendor_command(struct cypress *dev, unsigned char request, 70 unsigned char address, unsigned char data) 71 { 72 int retval = 0; 73 unsigned int pipe; 74 unsigned char *iobuf; 75 76 /* allocate some memory for the i/o buffer*/ 77 iobuf = kzalloc(CYPRESS_MAX_REQSIZE, GFP_KERNEL); 78 if (!iobuf) { 79 retval = -ENOMEM; 80 goto error; 81 } 82 83 dev_dbg(&dev->udev->dev, "Sending usb_control_msg (data: %d)\n", data); 84 85 /* prepare usb control message and send it upstream */ 86 pipe = usb_rcvctrlpipe(dev->udev, 0); 87 retval = usb_control_msg(dev->udev, pipe, request, 88 USB_DIR_IN | USB_TYPE_VENDOR | USB_RECIP_OTHER, 89 address, data, iobuf, CYPRESS_MAX_REQSIZE, 90 USB_CTRL_GET_TIMEOUT); 91 /* we must not process garbage */ 92 if (retval < 2) 93 goto err_buf; 94 95 /* store returned data (more READs to be added) */ 96 switch (request) { 97 case CYPRESS_READ_PORT: 98 if (address == CYPRESS_READ_PORT_ID0) { 99 dev->port[0] = iobuf[1]; 100 dev_dbg(&dev->udev->dev, 101 "READ_PORT0 returned: %d\n", 102 dev->port[0]); 103 } 104 else if (address == CYPRESS_READ_PORT_ID1) { 105 dev->port[1] = iobuf[1]; 106 dev_dbg(&dev->udev->dev, 107 "READ_PORT1 returned: %d\n", 108 dev->port[1]); 109 } 110 break; 111 } 112 113 err_buf: 114 kfree(iobuf); 115 error: 116 return retval; 117 } 118 119 /* write port value */ 120 static ssize_t write_port(struct device *dev, struct device_attribute *attr, 121 const char *buf, size_t count, 122 int port_num, int write_id) 123 { 124 int value = -1; 125 int result = 0; 126 127 struct usb_interface *intf = to_usb_interface(dev); 128 struct cypress *cyp = usb_get_intfdata(intf); 129 130 dev_dbg(&cyp->udev->dev, "WRITE_PORT%d called\n", port_num); 131 132 /* validate input data */ 133 if (sscanf(buf, "%d", &value) < 1) { 134 result = -EINVAL; 135 goto error; 136 } 137 if (value < 0 || value > 255) { 138 result = -EINVAL; 139 goto error; 140 } 141 142 result = vendor_command(cyp, CYPRESS_WRITE_PORT, write_id, 143 (unsigned char)value); 144 145 dev_dbg(&cyp->udev->dev, "Result of vendor_command: %d\n\n", result); 146 error: 147 return result < 0 ? result : count; 148 } 149 150 /* attribute callback handler (write) */ 151 static ssize_t port0_store(struct device *dev, 152 struct device_attribute *attr, 153 const char *buf, size_t count) 154 { 155 return write_port(dev, attr, buf, count, 0, CYPRESS_WRITE_PORT_ID0); 156 } 157 158 /* attribute callback handler (write) */ 159 static ssize_t port1_store(struct device *dev, 160 struct device_attribute *attr, 161 const char *buf, size_t count) 162 { 163 return write_port(dev, attr, buf, count, 1, CYPRESS_WRITE_PORT_ID1); 164 } 165 166 /* read port value */ 167 static ssize_t read_port(struct device *dev, struct device_attribute *attr, 168 char *buf, int port_num, int read_id) 169 { 170 int result = 0; 171 172 struct usb_interface *intf = to_usb_interface(dev); 173 struct cypress *cyp = usb_get_intfdata(intf); 174 175 dev_dbg(&cyp->udev->dev, "READ_PORT%d called\n", port_num); 176 177 result = vendor_command(cyp, CYPRESS_READ_PORT, read_id, 0); 178 179 dev_dbg(&cyp->udev->dev, "Result of vendor_command: %d\n\n", result); 180 181 return sprintf(buf, "%d", cyp->port[port_num]); 182 } 183 184 /* attribute callback handler (read) */ 185 static ssize_t port0_show(struct device *dev, 186 struct device_attribute *attr, char *buf) 187 { 188 return read_port(dev, attr, buf, 0, CYPRESS_READ_PORT_ID0); 189 } 190 static DEVICE_ATTR_RW(port0); 191 192 /* attribute callback handler (read) */ 193 static ssize_t port1_show(struct device *dev, 194 struct device_attribute *attr, char *buf) 195 { 196 return read_port(dev, attr, buf, 1, CYPRESS_READ_PORT_ID1); 197 } 198 static DEVICE_ATTR_RW(port1); 199 200 static struct attribute *cypress_attrs[] = { 201 &dev_attr_port0.attr, 202 &dev_attr_port1.attr, 203 NULL, 204 }; 205 ATTRIBUTE_GROUPS(cypress); 206 207 static int cypress_probe(struct usb_interface *interface, 208 const struct usb_device_id *id) 209 { 210 struct cypress *dev; 211 int retval = -ENOMEM; 212 213 /* allocate memory for our device state and initialize it */ 214 dev = kzalloc(sizeof(*dev), GFP_KERNEL); 215 if (!dev) 216 goto error_mem; 217 218 dev->udev = usb_get_dev(interface_to_usbdev(interface)); 219 220 /* save our data pointer in this interface device */ 221 usb_set_intfdata(interface, dev); 222 223 /* let the user know that the device is now attached */ 224 dev_info(&interface->dev, 225 "Cypress CY7C63xxx device now attached\n"); 226 return 0; 227 228 error_mem: 229 return retval; 230 } 231 232 static void cypress_disconnect(struct usb_interface *interface) 233 { 234 struct cypress *dev; 235 236 dev = usb_get_intfdata(interface); 237 238 /* the intfdata can be set to NULL only after the 239 * device files have been removed */ 240 usb_set_intfdata(interface, NULL); 241 242 usb_put_dev(dev->udev); 243 244 dev_info(&interface->dev, 245 "Cypress CY7C63xxx device now disconnected\n"); 246 247 kfree(dev); 248 } 249 250 static struct usb_driver cypress_driver = { 251 .name = "cypress_cy7c63", 252 .probe = cypress_probe, 253 .disconnect = cypress_disconnect, 254 .id_table = cypress_table, 255 .dev_groups = cypress_groups, 256 }; 257 258 module_usb_driver(cypress_driver); 259 260 MODULE_AUTHOR(DRIVER_AUTHOR); 261 MODULE_DESCRIPTION(DRIVER_DESC); 262 263 MODULE_LICENSE("GPL"); 264