linux/drivers/media/video/sn9c102/sn9c102_tas5130d1b.c
Trent Piepho c680dd6038 V4L/DVB (5502): Sn9c102: more efficient register writing code
There were many places in the driver which had long sequences of constant
register initializations.  These were done with one function call per
register.  The register address and value were immediate values in the
function calls.
This is very inefficient, as each register and value take twice the space
when they are code, as each includes a push instruction to put it on
the stack.  There there is the overhead, both size and time, for a
function call for each register.  It's also quite a few lines of C code
to do this.
The patch creates a function that writes multiple registers from a list,
and a macro that makes it easy to construct a such a list as a const
static local to send to the function.
This gets rid of quite a bit of C code, and shrinks the driver by around
8k, while at the same time being more efficient.
Acked-by: Luca Risolia <luca.risolia@studio.unibo.it>

Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
2007-04-27 15:45:27 -03:00

165 lines
4.5 KiB
C

/***************************************************************************
* Plug-in for TAS5130D1B image sensor connected to the SN9C1xx PC Camera *
* Controllers *
* *
* Copyright (C) 2004-2007 by Luca Risolia <luca.risolia@studio.unibo.it> *
* *
* This program is free software; you can redistribute it and/or modify *
* it under the terms of the GNU General Public License as published by *
* the Free Software Foundation; either version 2 of the License, or *
* (at your option) any later version. *
* *
* This program is distributed in the hope that it will be useful, *
* but WITHOUT ANY WARRANTY; without even the implied warranty of *
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
* GNU General Public License for more details. *
* *
* You should have received a copy of the GNU General Public License *
* along with this program; if not, write to the Free Software *
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. *
***************************************************************************/
#include "sn9c102_sensor.h"
static int tas5130d1b_init(struct sn9c102_device* cam)
{
int err;
err = sn9c102_write_const_regs(cam, {0x01, 0x01}, {0x20, 0x17},
{0x04, 0x01}, {0x01, 0x10},
{0x00, 0x11}, {0x00, 0x14},
{0x60, 0x17}, {0x07, 0x18});
return err;
}
static int tas5130d1b_set_ctrl(struct sn9c102_device* cam,
const struct v4l2_control* ctrl)
{
int err = 0;
switch (ctrl->id) {
case V4L2_CID_GAIN:
err += sn9c102_i2c_write(cam, 0x20, 0xf6 - ctrl->value);
break;
case V4L2_CID_EXPOSURE:
err += sn9c102_i2c_write(cam, 0x40, 0x47 - ctrl->value);
break;
default:
return -EINVAL;
}
return err ? -EIO : 0;
}
static int tas5130d1b_set_crop(struct sn9c102_device* cam,
const struct v4l2_rect* rect)
{
struct sn9c102_sensor* s = sn9c102_get_sensor(cam);
u8 h_start = (u8)(rect->left - s->cropcap.bounds.left) + 104,
v_start = (u8)(rect->top - s->cropcap.bounds.top) + 12;
int err = 0;
err += sn9c102_write_reg(cam, h_start, 0x12);
err += sn9c102_write_reg(cam, v_start, 0x13);
/* Do NOT change! */
err += sn9c102_write_reg(cam, 0x1f, 0x1a);
err += sn9c102_write_reg(cam, 0x1a, 0x1b);
err += sn9c102_write_reg(cam, sn9c102_pread_reg(cam, 0x19), 0x19);
return err;
}
static int tas5130d1b_set_pix_format(struct sn9c102_device* cam,
const struct v4l2_pix_format* pix)
{
int err = 0;
if (pix->pixelformat == V4L2_PIX_FMT_SN9C10X)
err += sn9c102_write_reg(cam, 0x63, 0x19);
else
err += sn9c102_write_reg(cam, 0xf3, 0x19);
return err;
}
static struct sn9c102_sensor tas5130d1b = {
.name = "TAS5130D1B",
.maintainer = "Luca Risolia <luca.risolia@studio.unibo.it>",
.supported_bridge = BRIDGE_SN9C101 | BRIDGE_SN9C102,
.sysfs_ops = SN9C102_I2C_WRITE,
.frequency = SN9C102_I2C_100KHZ,
.interface = SN9C102_I2C_3WIRES,
.init = &tas5130d1b_init,
.qctrl = {
{
.id = V4L2_CID_GAIN,
.type = V4L2_CTRL_TYPE_INTEGER,
.name = "global gain",
.minimum = 0x00,
.maximum = 0xf6,
.step = 0x02,
.default_value = 0x00,
.flags = 0,
},
{
.id = V4L2_CID_EXPOSURE,
.type = V4L2_CTRL_TYPE_INTEGER,
.name = "exposure",
.minimum = 0x00,
.maximum = 0x47,
.step = 0x01,
.default_value = 0x00,
.flags = 0,
},
},
.set_ctrl = &tas5130d1b_set_ctrl,
.cropcap = {
.bounds = {
.left = 0,
.top = 0,
.width = 640,
.height = 480,
},
.defrect = {
.left = 0,
.top = 0,
.width = 640,
.height = 480,
},
},
.set_crop = &tas5130d1b_set_crop,
.pix_format = {
.width = 640,
.height = 480,
.pixelformat = V4L2_PIX_FMT_SBGGR8,
.priv = 8,
},
.set_pix_format = &tas5130d1b_set_pix_format
};
int sn9c102_probe_tas5130d1b(struct sn9c102_device* cam)
{
const struct usb_device_id tas5130d1b_id_table[] = {
{ USB_DEVICE(0x0c45, 0x6024), },
{ USB_DEVICE(0x0c45, 0x6025), },
{ USB_DEVICE(0x0c45, 0x60aa), },
{ }
};
/* Sensor detection is based on USB pid/vid */
if (!sn9c102_match_id(cam, tas5130d1b_id_table))
return -ENODEV;
sn9c102_attach_sensor(cam, &tas5130d1b);
return 0;
}