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/i2c-algo-bit.h>
  21 #include <linux/firmware.h>
  22 #include <media/v4l2-common.h>
  23 #include <media/cx25840.h>
  24
  25 #include "cx25840-core.h"
  26
  27 #define FWFILE "v4l-cx25840.fw"
  28
  29 /*
  30  * Mike Isely <isely@pobox.com> - The FWSEND parameter controls the
  31  * size of the firmware chunks sent down the I2C bus to the chip.
  32  * Previously this had been set to 1024 but unfortunately some I2C
  33  * implementations can't transfer data in such big gulps.
  34  * Specifically, the pvrusb2 driver has a hard limit of around 60
  35  * bytes, due to the encapsulation there of I2C traffic into USB
  36  * messages.  So we have to significantly reduce this parameter.
  37  */
  38 #define FWSEND 48
  39
  40 #define FWDEV(x) &((x)->adapter->dev)
  41
  42 static char *firmware = FWFILE;
  43
  44 module_param(firmware, charp, 0444);
  45
  46 MODULE_PARM_DESC(firmware, "Firmware image [default: " FWFILE "]");
  47
  48 static void start_fw_load(struct i2c_client *client)
  49 {
  50         /* DL_ADDR_LB=0 DL_ADDR_HB=0 */
  51         cx25840_write(client, 0x800, 0x00);
  52         cx25840_write(client, 0x801, 0x00);
  53         // DL_MAP=3 DL_AUTO_INC=0 DL_ENABLE=1
  54         cx25840_write(client, 0x803, 0x0b);
  55         /* AUTO_INC_DIS=1 */
  56         cx25840_write(client, 0x000, 0x20);
  57 }
  58
  59 static void end_fw_load(struct i2c_client *client)
  60 {
  61         /* AUTO_INC_DIS=0 */
  62         cx25840_write(client, 0x000, 0x00);
  63         /* DL_ENABLE=0 */
  64         cx25840_write(client, 0x803, 0x03);
  65 }
  66
  67 static int check_fw_load(struct i2c_client *client, int size)
  68 {
  69         /* DL_ADDR_HB DL_ADDR_LB */
  70         int s = cx25840_read(client, 0x801) << 8;
  71         s |= cx25840_read(client, 0x800);
  72
  73         if (size != s) {
  74                 v4l_err(client, "firmware %s load failed\n", firmware);
  75                 return -EINVAL;
  76         }
  77
  78         v4l_info(client, "loaded %s firmware (%d bytes)\n", firmware, size);
  79         return 0;
  80 }
  81
  82 static int fw_write(struct i2c_client *client, u8 * data, int size)
  83 {
  84         int sent;
  85
  86         if ((sent = i2c_master_send(client, data, size)) < size) {
  87                 v4l_err(client, "firmware load i2c failure\n");
  88                 return -ENOSYS;
  89         }
  90
  91         return 0;
  92 }
  93
  94 int cx25840_loadfw(struct i2c_client *client)
  95 {
  96         const struct firmware *fw = NULL;
  97         u8 buffer[4], *ptr;
  98         int size, send, retval;
  99
 100         if (request_firmware(&fw, firmware, FWDEV(client)) != 0) {
 101                 v4l_err(client, "unable to open firmware %s\n", firmware);
 102                 return -EINVAL;
 103         }
 104
 105         start_fw_load(client);
 106
 107         buffer[0] = 0x08;
 108         buffer[1] = 0x02;
 109         buffer[2] = fw->data[0];
 110         buffer[3] = fw->data[1];
 111         retval = fw_write(client, buffer, 4);
 112
 113         if (retval < 0) {
 114                 release_firmware(fw);
 115                 return retval;
 116         }
 117
 118         size = fw->size - 2;
 119         ptr = fw->data;
 120         while (size > 0) {
 121                 ptr[0] = 0x08;
 122                 ptr[1] = 0x02;
 123                 send = size > (FWSEND - 2) ? FWSEND : size + 2;
 124                 retval = fw_write(client, ptr, send);
 125
 126                 if (retval < 0) {
 127                         release_firmware(fw);
 128                         return retval;
 129                 }
 130
 131                 size -= FWSEND - 2;
 132                 ptr += FWSEND - 2;
 133         }
 134
 135         end_fw_load(client);
 136
 137         size = fw->size;
 138         release_firmware(fw);
 139
 140         return check_fw_load(client, size);
 141 }