[media] dvb-usb-firmware: don't do DMA on stack
[sfrench/cifs-2.6.git] / drivers / media / usb / dvb-usb / dvb-usb-firmware.c
1 /* dvb-usb-firmware.c is part of the DVB USB library.
2  *
3  * Copyright (C) 2004-6 Patrick Boettcher (patrick.boettcher@posteo.de)
4  * see dvb-usb-init.c for copyright information.
5  *
6  * This file contains functions for downloading the firmware to Cypress FX 1 and 2 based devices.
7  *
8  * FIXME: This part does actually not belong to dvb-usb, but to the usb-subsystem.
9  */
10 #include "dvb-usb-common.h"
11
12 #include <linux/usb.h>
13
14 struct usb_cypress_controller {
15         int id;
16         const char *name;       /* name of the usb controller */
17         u16 cpu_cs_register;    /* needs to be restarted, when the firmware has been downloaded. */
18 };
19
20 static struct usb_cypress_controller cypress[] = {
21         { .id = DEVICE_SPECIFIC, .name = "Device specific", .cpu_cs_register = 0 },
22         { .id = CYPRESS_AN2135,  .name = "Cypress AN2135",  .cpu_cs_register = 0x7f92 },
23         { .id = CYPRESS_AN2235,  .name = "Cypress AN2235",  .cpu_cs_register = 0x7f92 },
24         { .id = CYPRESS_FX2,     .name = "Cypress FX2",     .cpu_cs_register = 0xe600 },
25 };
26
27 /*
28  * load a firmware packet to the device
29  */
30 static int usb_cypress_writemem(struct usb_device *udev,u16 addr,u8 *data, u8 len)
31 {
32         return usb_control_msg(udev, usb_sndctrlpipe(udev,0),
33                         0xa0, USB_TYPE_VENDOR, addr, 0x00, data, len, 5000);
34 }
35
36 int usb_cypress_load_firmware(struct usb_device *udev, const struct firmware *fw, int type)
37 {
38         struct hexline *hx;
39         u8 *buf;
40         int ret, pos = 0;
41         u16 cpu_cs_register = cypress[type].cpu_cs_register;
42
43         buf = kmalloc(sizeof(*hx), GFP_KERNEL);
44         if (!buf)
45                 return -ENOMEM;
46         hx = (struct hexline *)buf;
47
48         /* stop the CPU */
49         buf[0] = 1;
50         if (usb_cypress_writemem(udev, cpu_cs_register, buf, 1) != 1)
51                 err("could not stop the USB controller CPU.");
52
53         while ((ret = dvb_usb_get_hexline(fw, hx, &pos)) > 0) {
54                 deb_fw("writing to address 0x%04x (buffer: 0x%02x %02x)\n", hx->addr, hx->len, hx->chk);
55                 ret = usb_cypress_writemem(udev, hx->addr, hx->data, hx->len);
56
57                 if (ret != hx->len) {
58                         err("error while transferring firmware (transferred size: %d, block size: %d)",
59                                 ret, hx->len);
60                         ret = -EINVAL;
61                         break;
62                 }
63         }
64         if (ret < 0) {
65                 err("firmware download failed at %d with %d",pos,ret);
66                 kfree(buf);
67                 return ret;
68         }
69
70         if (ret == 0) {
71                 /* restart the CPU */
72                 buf[0] = 0;
73                 if (usb_cypress_writemem(udev, cpu_cs_register, buf, 1) != 1) {
74                         err("could not restart the USB controller CPU.");
75                         ret = -EINVAL;
76                 }
77         } else
78                 ret = -EIO;
79
80         kfree(buf);
81
82         return ret;
83 }
84 EXPORT_SYMBOL(usb_cypress_load_firmware);
85
86 int dvb_usb_download_firmware(struct usb_device *udev, struct dvb_usb_device_properties *props)
87 {
88         int ret;
89         const struct firmware *fw = NULL;
90
91         if ((ret = request_firmware(&fw, props->firmware, &udev->dev)) != 0) {
92                 err("did not find the firmware file. (%s) Please see linux/Documentation/dvb/ for more details on firmware-problems. (%d)",
93                         props->firmware,ret);
94                 return ret;
95         }
96
97         info("downloading firmware from file '%s'",props->firmware);
98
99         switch (props->usb_ctrl) {
100                 case CYPRESS_AN2135:
101                 case CYPRESS_AN2235:
102                 case CYPRESS_FX2:
103                         ret = usb_cypress_load_firmware(udev, fw, props->usb_ctrl);
104                         break;
105                 case DEVICE_SPECIFIC:
106                         if (props->download_firmware)
107                                 ret = props->download_firmware(udev,fw);
108                         else {
109                                 err("BUG: driver didn't specified a download_firmware-callback, although it claims to have a DEVICE_SPECIFIC one.");
110                                 ret = -EINVAL;
111                         }
112                         break;
113                 default:
114                         ret = -EINVAL;
115                         break;
116         }
117
118         release_firmware(fw);
119         return ret;
120 }
121
122 int dvb_usb_get_hexline(const struct firmware *fw, struct hexline *hx,
123                                int *pos)
124 {
125         u8 *b = (u8 *) &fw->data[*pos];
126         int data_offs = 4;
127         if (*pos >= fw->size)
128                 return 0;
129
130         memset(hx,0,sizeof(struct hexline));
131
132         hx->len  = b[0];
133
134         if ((*pos + hx->len + 4) >= fw->size)
135                 return -EINVAL;
136
137         hx->addr = b[1] | (b[2] << 8);
138         hx->type = b[3];
139
140         if (hx->type == 0x04) {
141                 /* b[4] and b[5] are the Extended linear address record data field */
142                 hx->addr |= (b[4] << 24) | (b[5] << 16);
143 /*              hx->len -= 2;
144                 data_offs += 2; */
145         }
146         memcpy(hx->data,&b[data_offs],hx->len);
147         hx->chk = b[hx->len + data_offs];
148
149         *pos += hx->len + 5;
150
151         return *pos;
152 }
153 EXPORT_SYMBOL(dvb_usb_get_hexline);