1 // SPDX-License-Identifier: GPL-2.0+ 2 /* 3 * Driver for Option High Speed Mobile Devices. 4 * 5 * (c) 2008 Dan Williams <dcbw@redhat.com> 6 * 7 * Inspiration taken from sierra_ms.c by Kevin Lloyd <klloyd@sierrawireless.com> 8 */ 9 10 #include <linux/usb.h> 11 #include <linux/slab.h> 12 #include <linux/module.h> 13 14 #include "usb.h" 15 #include "transport.h" 16 #include "option_ms.h" 17 #include "debug.h" 18 19 #define ZCD_FORCE_MODEM 0x01 20 #define ZCD_ALLOW_MS 0x02 21 22 static unsigned int option_zero_cd = ZCD_FORCE_MODEM; 23 module_param(option_zero_cd, uint, S_IRUGO | S_IWUSR); 24 MODULE_PARM_DESC(option_zero_cd, "ZeroCD mode (1=Force Modem (default)," 25 " 2=Allow CD-Rom"); 26 27 #define RESPONSE_LEN 1024 28 29 static int option_rezero(struct us_data *us) 30 { 31 static const unsigned char rezero_msg[] = { 32 0x55, 0x53, 0x42, 0x43, 0x78, 0x56, 0x34, 0x12, 33 0x01, 0x00, 0x00, 0x00, 0x80, 0x00, 0x06, 0x01, 34 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 35 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 36 }; 37 char *buffer; 38 int result; 39 40 usb_stor_dbg(us, "Option MS: %s\n", "DEVICE MODE SWITCH"); 41 42 buffer = kzalloc(RESPONSE_LEN, GFP_KERNEL); 43 if (buffer == NULL) 44 return USB_STOR_TRANSPORT_ERROR; 45 46 memcpy(buffer, rezero_msg, sizeof(rezero_msg)); 47 result = usb_stor_bulk_transfer_buf(us, 48 us->send_bulk_pipe, 49 buffer, sizeof(rezero_msg), NULL); 50 if (result != USB_STOR_XFER_GOOD) { 51 result = USB_STOR_XFER_ERROR; 52 goto out; 53 } 54 55 /* 56 * Some of the devices need to be asked for a response, but we don't 57 * care what that response is. 58 */ 59 usb_stor_bulk_transfer_buf(us, 60 us->recv_bulk_pipe, 61 buffer, RESPONSE_LEN, NULL); 62 63 /* Read the CSW */ 64 usb_stor_bulk_transfer_buf(us, 65 us->recv_bulk_pipe, 66 buffer, 13, NULL); 67 68 result = USB_STOR_XFER_GOOD; 69 70 out: 71 kfree(buffer); 72 return result; 73 } 74 75 static int option_inquiry(struct us_data *us) 76 { 77 static const unsigned char inquiry_msg[] = { 78 0x55, 0x53, 0x42, 0x43, 0x12, 0x34, 0x56, 0x78, 79 0x24, 0x00, 0x00, 0x00, 0x80, 0x00, 0x06, 0x12, 80 0x00, 0x00, 0x00, 0x24, 0x00, 0x00, 0x00, 0x00, 81 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 82 }; 83 char *buffer; 84 int result; 85 86 usb_stor_dbg(us, "Option MS: %s\n", "device inquiry for vendor name"); 87 88 buffer = kzalloc(0x24, GFP_KERNEL); 89 if (buffer == NULL) 90 return USB_STOR_TRANSPORT_ERROR; 91 92 memcpy(buffer, inquiry_msg, sizeof(inquiry_msg)); 93 result = usb_stor_bulk_transfer_buf(us, 94 us->send_bulk_pipe, 95 buffer, sizeof(inquiry_msg), NULL); 96 if (result != USB_STOR_XFER_GOOD) { 97 result = USB_STOR_XFER_ERROR; 98 goto out; 99 } 100 101 result = usb_stor_bulk_transfer_buf(us, 102 us->recv_bulk_pipe, 103 buffer, 0x24, NULL); 104 if (result != USB_STOR_XFER_GOOD) { 105 result = USB_STOR_XFER_ERROR; 106 goto out; 107 } 108 109 result = memcmp(buffer+8, "Option", 6); 110 111 if (result != 0) 112 result = memcmp(buffer+8, "ZCOPTION", 8); 113 114 /* Read the CSW */ 115 usb_stor_bulk_transfer_buf(us, 116 us->recv_bulk_pipe, 117 buffer, 13, NULL); 118 119 out: 120 kfree(buffer); 121 return result; 122 } 123 124 125 int option_ms_init(struct us_data *us) 126 { 127 int result; 128 129 usb_stor_dbg(us, "Option MS: %s\n", "option_ms_init called"); 130 131 /* 132 * Additional test for vendor information via INQUIRY, 133 * because some vendor/product IDs are ambiguous 134 */ 135 result = option_inquiry(us); 136 if (result != 0) { 137 usb_stor_dbg(us, "Option MS: %s\n", 138 "vendor is not Option or not determinable, no action taken"); 139 return 0; 140 } else 141 usb_stor_dbg(us, "Option MS: %s\n", 142 "this is a genuine Option device, proceeding"); 143 144 /* Force Modem mode */ 145 if (option_zero_cd == ZCD_FORCE_MODEM) { 146 usb_stor_dbg(us, "Option MS: %s\n", "Forcing Modem Mode"); 147 result = option_rezero(us); 148 if (result != USB_STOR_XFER_GOOD) 149 usb_stor_dbg(us, "Option MS: %s\n", 150 "Failed to switch to modem mode"); 151 return -EIO; 152 } else if (option_zero_cd == ZCD_ALLOW_MS) { 153 /* Allow Mass Storage mode (keep CD-Rom) */ 154 usb_stor_dbg(us, "Option MS: %s\n", 155 "Allowing Mass Storage Mode if device requests it"); 156 } 157 158 return 0; 159 } 160 161