drivers/media/video/cx25840/cx25840-firmware.c

   1 /* cx25840 firmware functions
   2  *
   3  * This program is free software; you can redistribute it and/or
   4  * modify it under the terms of the GNU General Public License
   5  * as published by the Free Software Foundation; either version 2
   6  * of the License, or (at your option) any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program; if not, write to the Free Software
  15  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
  16  */
  17
  18 #include <linux/module.h>
  19 #include <linux/i2c.h>
  20 #include <linux/firmware.h>
  21 #include <media/v4l2-common.h>
  22 #include <media/cx25840.h>
  23
  24 #include "cx25840-core.h"
  25
  26 #define FWFILE "v4l-cx25840.fw"
  27
  28 /*
  29  * Mike Isely <isely@pobox.com> - The FWSEND parameter controls the
  30  * size of the firmware chunks sent down the I2C bus to the chip.
  31  * Previously this had been set to 1024 but unfortunately some I2C
  32  * implementations can't transfer data in such big gulps.
  33  * Specifically, the pvrusb2 driver has a hard limit of around 60
  34  * bytes, due to the encapsulation there of I2C traffic into USB
  35  * messages.  So we have to significantly reduce this parameter.
  36  */
  37 #define FWSEND 48
  38
  39 #define FWDEV(x) &((x)->dev)
  40
  41 static char *firmware = FWFILE;
  42
  43 module_param(firmware, charp, 0444);
  44
  45 MODULE_PARM_DESC(firmware, "Firmware image [default: " FWFILE "]");
  46
  47 static void start_fw_load(struct i2c_client *client)
  48 {
  49         /* DL_ADDR_LB=0 DL_ADDR_HB=0 */
  50         cx25840_write(client, 0x800, 0x00);
  51         cx25840_write(client, 0x801, 0x00);
  52         // DL_MAP=3 DL_AUTO_INC=0 DL_ENABLE=1
  53         cx25840_write(client, 0x803, 0x0b);
  54         /* AUTO_INC_DIS=1 */
  55         cx25840_write(client, 0x000, 0x20);
  56 }
  57
  58 static void end_fw_load(struct i2c_client *client)
  59 {
  60         /* AUTO_INC_DIS=0 */
  61         cx25840_write(client, 0x000, 0x00);
  62         /* DL_ENABLE=0 */
  63         cx25840_write(client, 0x803, 0x03);
  64 }
  65
  66 static int check_fw_load(struct i2c_client *client, int size)
  67 {
  68         /* DL_ADDR_HB DL_ADDR_LB */
  69         int s = cx25840_read(client, 0x801) << 8;
  70         s |= cx25840_read(client, 0x800);
  71
  72         if (size != s) {
  73                 v4l_err(client, "firmware %s load failed\n", firmware);
  74                 return -EINVAL;
  75         }
  76
  77         v4l_info(client, "loaded %s firmware (%d bytes)\n", firmware, size);
  78         return 0;
  79 }
  80
  81 static int fw_write(struct i2c_client *client, u8 * data, int size)
  82 {
  83         int sent;
  84
  85         if ((sent = i2c_master_send(client, data, size)) < size) {
  86                 v4l_err(client, "firmware load i2c failure\n");
  87                 return -ENOSYS;
  88         }
  89
  90         return 0;
  91 }
  92
  93 int cx25840_loadfw(struct i2c_client *client)
  94 {
  95         const struct firmware *fw = NULL;
  96         u8 buffer[4], *ptr;
  97         int size, send, retval;
  98
  99         if (request_firmware(&fw, firmware, FWDEV(client)) != 0) {
 100                 v4l_err(client, "unable to open firmware %s\n", firmware);
 101                 return -EINVAL;
 102         }
 103
 104         start_fw_load(client);
 105
 106         buffer[0] = 0x08;
 107         buffer[1] = 0x02;
 108         buffer[2] = fw->data[0];
 109         buffer[3] = fw->data[1];
 110         retval = fw_write(client, buffer, 4);
 111
 112         if (retval < 0) {
 113                 release_firmware(fw);
 114                 return retval;
 115         }
 116
 117         size = fw->size - 2;
 118         ptr = fw->data;
 119         while (size > 0) {
 120                 ptr[0] = 0x08;
 121                 ptr[1] = 0x02;
 122                 send = size > (FWSEND - 2) ? FWSEND : size + 2;
 123                 retval = fw_write(client, ptr, send);
 124
 125                 if (retval < 0) {
 126                         release_firmware(fw);
 127                         return retval;
 128                 }
 129
 130                 size -= FWSEND - 2;
 131                 ptr += FWSEND - 2;
 132         }
 133
 134         end_fw_load(client);
 135
 136         size = fw->size;
 137         release_firmware(fw);
 138
 139         return check_fw_load(client, size);
 140 }