linux/drivers/media/video/mt9v011.c
Johannes Obermaier 32127363ee [media] mt9v011: Fixed gain calculation
The implementation of the gain calculation for this sensor is incorrect.
It is only working for the first 127 values.

The reason is, that the gain cannot be set directly by writing a value
into the gain registers of the sensor. The gain register work this way
(see datasheet page 24): bits 0 to 6 are called "initial gain". These
are linear. But bits 7 and 8 ("analog multiplicative factors") and bits
9 and 10 ("digital multiplicative factors") work completely different:
Each of these bits increase the gain by the factor 2. So if the bits
7-10 are 0011, 0110, 1100 or 0101 for example, the gain from bits 0-6 is
multiplied by 4. The order of the bits 7-10 is not important for the
resulting gain. (But there are some recommended values for low noise)

The current driver doesn't do this correctly: If the current gain is 000
0111 1111 (127) and the gain is increased by 1, you would expect the
image to become brighter. But the image is completly dark, because the
new gain is 000 1000 0000 (128). This means: Initial gain of 0,
multiplied by 2. The result is 0.

This patch adds a new function which does the gain calculation and also
fixes the same bug for red_balance and blue_balance. Additionally, the
driver follows the recommendation from the datasheet, which says, that
the gain should always be above 0x0020.

Tested-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Johannes Obermaier <johannes.obermaier@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
2011-07-27 17:52:25 -03:00

723 lines
17 KiB
C

/*
* mt9v011 -Micron 1/4-Inch VGA Digital Image Sensor
*
* Copyright (c) 2009 Mauro Carvalho Chehab (mchehab@redhat.com)
* This code is placed under the terms of the GNU General Public License v2
*/
#include <linux/i2c.h>
#include <linux/slab.h>
#include <linux/videodev2.h>
#include <linux/delay.h>
#include <asm/div64.h>
#include <media/v4l2-device.h>
#include <media/v4l2-chip-ident.h>
#include <media/mt9v011.h>
MODULE_DESCRIPTION("Micron mt9v011 sensor driver");
MODULE_AUTHOR("Mauro Carvalho Chehab <mchehab@redhat.com>");
MODULE_LICENSE("GPL");
static int debug;
module_param(debug, int, 0);
MODULE_PARM_DESC(debug, "Debug level (0-2)");
#define R00_MT9V011_CHIP_VERSION 0x00
#define R01_MT9V011_ROWSTART 0x01
#define R02_MT9V011_COLSTART 0x02
#define R03_MT9V011_HEIGHT 0x03
#define R04_MT9V011_WIDTH 0x04
#define R05_MT9V011_HBLANK 0x05
#define R06_MT9V011_VBLANK 0x06
#define R07_MT9V011_OUT_CTRL 0x07
#define R09_MT9V011_SHUTTER_WIDTH 0x09
#define R0A_MT9V011_CLK_SPEED 0x0a
#define R0B_MT9V011_RESTART 0x0b
#define R0C_MT9V011_SHUTTER_DELAY 0x0c
#define R0D_MT9V011_RESET 0x0d
#define R1E_MT9V011_DIGITAL_ZOOM 0x1e
#define R20_MT9V011_READ_MODE 0x20
#define R2B_MT9V011_GREEN_1_GAIN 0x2b
#define R2C_MT9V011_BLUE_GAIN 0x2c
#define R2D_MT9V011_RED_GAIN 0x2d
#define R2E_MT9V011_GREEN_2_GAIN 0x2e
#define R35_MT9V011_GLOBAL_GAIN 0x35
#define RF1_MT9V011_CHIP_ENABLE 0xf1
#define MT9V011_VERSION 0x8232
#define MT9V011_REV_B_VERSION 0x8243
/* supported controls */
static struct v4l2_queryctrl mt9v011_qctrl[] = {
{
.id = V4L2_CID_GAIN,
.type = V4L2_CTRL_TYPE_INTEGER,
.name = "Gain",
.minimum = 0,
.maximum = (1 << 12) - 1 - 0x0020,
.step = 1,
.default_value = 0x0020,
.flags = 0,
}, {
.id = V4L2_CID_EXPOSURE,
.type = V4L2_CTRL_TYPE_INTEGER,
.name = "Exposure",
.minimum = 0,
.maximum = 2047,
.step = 1,
.default_value = 0x01fc,
.flags = 0,
}, {
.id = V4L2_CID_RED_BALANCE,
.type = V4L2_CTRL_TYPE_INTEGER,
.name = "Red Balance",
.minimum = -1 << 9,
.maximum = (1 << 9) - 1,
.step = 1,
.default_value = 0,
.flags = 0,
}, {
.id = V4L2_CID_BLUE_BALANCE,
.type = V4L2_CTRL_TYPE_INTEGER,
.name = "Blue Balance",
.minimum = -1 << 9,
.maximum = (1 << 9) - 1,
.step = 1,
.default_value = 0,
.flags = 0,
}, {
.id = V4L2_CID_HFLIP,
.type = V4L2_CTRL_TYPE_BOOLEAN,
.name = "Mirror",
.minimum = 0,
.maximum = 1,
.step = 1,
.default_value = 0,
.flags = 0,
}, {
.id = V4L2_CID_VFLIP,
.type = V4L2_CTRL_TYPE_BOOLEAN,
.name = "Vflip",
.minimum = 0,
.maximum = 1,
.step = 1,
.default_value = 0,
.flags = 0,
}, {
}
};
struct mt9v011 {
struct v4l2_subdev sd;
unsigned width, height;
unsigned xtal;
unsigned hflip:1;
unsigned vflip:1;
u16 global_gain, exposure;
s16 red_bal, blue_bal;
};
static inline struct mt9v011 *to_mt9v011(struct v4l2_subdev *sd)
{
return container_of(sd, struct mt9v011, sd);
}
static int mt9v011_read(struct v4l2_subdev *sd, unsigned char addr)
{
struct i2c_client *c = v4l2_get_subdevdata(sd);
__be16 buffer;
int rc, val;
rc = i2c_master_send(c, &addr, 1);
if (rc != 1)
v4l2_dbg(0, debug, sd,
"i2c i/o error: rc == %d (should be 1)\n", rc);
msleep(10);
rc = i2c_master_recv(c, (char *)&buffer, 2);
if (rc != 2)
v4l2_dbg(0, debug, sd,
"i2c i/o error: rc == %d (should be 2)\n", rc);
val = be16_to_cpu(buffer);
v4l2_dbg(2, debug, sd, "mt9v011: read 0x%02x = 0x%04x\n", addr, val);
return val;
}
static void mt9v011_write(struct v4l2_subdev *sd, unsigned char addr,
u16 value)
{
struct i2c_client *c = v4l2_get_subdevdata(sd);
unsigned char buffer[3];
int rc;
buffer[0] = addr;
buffer[1] = value >> 8;
buffer[2] = value & 0xff;
v4l2_dbg(2, debug, sd,
"mt9v011: writing 0x%02x 0x%04x\n", buffer[0], value);
rc = i2c_master_send(c, buffer, 3);
if (rc != 3)
v4l2_dbg(0, debug, sd,
"i2c i/o error: rc == %d (should be 3)\n", rc);
}
struct i2c_reg_value {
unsigned char reg;
u16 value;
};
/*
* Values used at the original driver
* Some values are marked as Reserved at the datasheet
*/
static const struct i2c_reg_value mt9v011_init_default[] = {
{ R0D_MT9V011_RESET, 0x0001 },
{ R0D_MT9V011_RESET, 0x0000 },
{ R0C_MT9V011_SHUTTER_DELAY, 0x0000 },
{ R09_MT9V011_SHUTTER_WIDTH, 0x1fc },
{ R0A_MT9V011_CLK_SPEED, 0x0000 },
{ R1E_MT9V011_DIGITAL_ZOOM, 0x0000 },
{ R07_MT9V011_OUT_CTRL, 0x0002 }, /* chip enable */
};
static u16 calc_mt9v011_gain(s16 lineargain)
{
u16 digitalgain = 0;
u16 analogmult = 0;
u16 analoginit = 0;
if (lineargain < 0)
lineargain = 0;
/* recommended minimum */
lineargain += 0x0020;
if (lineargain > 2047)
lineargain = 2047;
if (lineargain > 1023) {
digitalgain = 3;
analogmult = 3;
analoginit = lineargain / 16;
} else if (lineargain > 511) {
digitalgain = 1;
analogmult = 3;
analoginit = lineargain / 8;
} else if (lineargain > 255) {
analogmult = 3;
analoginit = lineargain / 4;
} else if (lineargain > 127) {
analogmult = 1;
analoginit = lineargain / 2;
} else
analoginit = lineargain;
return analoginit + (analogmult << 7) + (digitalgain << 9);
}
static void set_balance(struct v4l2_subdev *sd)
{
struct mt9v011 *core = to_mt9v011(sd);
u16 green_gain, blue_gain, red_gain;
u16 exposure;
s16 bal;
exposure = core->exposure;
green_gain = calc_mt9v011_gain(core->global_gain);
bal = core->global_gain;
bal += (core->blue_bal * core->global_gain / (1 << 7));
blue_gain = calc_mt9v011_gain(bal);
bal = core->global_gain;
bal += (core->red_bal * core->global_gain / (1 << 7));
red_gain = calc_mt9v011_gain(bal);
mt9v011_write(sd, R2B_MT9V011_GREEN_1_GAIN, green_gain);
mt9v011_write(sd, R2E_MT9V011_GREEN_2_GAIN, green_gain);
mt9v011_write(sd, R2C_MT9V011_BLUE_GAIN, blue_gain);
mt9v011_write(sd, R2D_MT9V011_RED_GAIN, red_gain);
mt9v011_write(sd, R09_MT9V011_SHUTTER_WIDTH, exposure);
}
static void calc_fps(struct v4l2_subdev *sd, u32 *numerator, u32 *denominator)
{
struct mt9v011 *core = to_mt9v011(sd);
unsigned height, width, hblank, vblank, speed;
unsigned row_time, t_time;
u64 frames_per_ms;
unsigned tmp;
height = mt9v011_read(sd, R03_MT9V011_HEIGHT);
width = mt9v011_read(sd, R04_MT9V011_WIDTH);
hblank = mt9v011_read(sd, R05_MT9V011_HBLANK);
vblank = mt9v011_read(sd, R06_MT9V011_VBLANK);
speed = mt9v011_read(sd, R0A_MT9V011_CLK_SPEED);
row_time = (width + 113 + hblank) * (speed + 2);
t_time = row_time * (height + vblank + 1);
frames_per_ms = core->xtal * 1000l;
do_div(frames_per_ms, t_time);
tmp = frames_per_ms;
v4l2_dbg(1, debug, sd, "Programmed to %u.%03u fps (%d pixel clcks)\n",
tmp / 1000, tmp % 1000, t_time);
if (numerator && denominator) {
*numerator = 1000;
*denominator = (u32)frames_per_ms;
}
}
static u16 calc_speed(struct v4l2_subdev *sd, u32 numerator, u32 denominator)
{
struct mt9v011 *core = to_mt9v011(sd);
unsigned height, width, hblank, vblank;
unsigned row_time, line_time;
u64 t_time, speed;
/* Avoid bogus calculus */
if (!numerator || !denominator)
return 0;
height = mt9v011_read(sd, R03_MT9V011_HEIGHT);
width = mt9v011_read(sd, R04_MT9V011_WIDTH);
hblank = mt9v011_read(sd, R05_MT9V011_HBLANK);
vblank = mt9v011_read(sd, R06_MT9V011_VBLANK);
row_time = width + 113 + hblank;
line_time = height + vblank + 1;
t_time = core->xtal * ((u64)numerator);
/* round to the closest value */
t_time += denominator / 2;
do_div(t_time, denominator);
speed = t_time;
do_div(speed, row_time * line_time);
/* Avoid having a negative value for speed */
if (speed < 2)
speed = 0;
else
speed -= 2;
/* Avoid speed overflow */
if (speed > 15)
return 15;
return (u16)speed;
}
static void set_res(struct v4l2_subdev *sd)
{
struct mt9v011 *core = to_mt9v011(sd);
unsigned vstart, hstart;
/*
* The mt9v011 doesn't have scaling. So, in order to select the desired
* resolution, we're cropping at the middle of the sensor.
* hblank and vblank should be adjusted, in order to warrant that
* we'll preserve the line timings for 30 fps, no matter what resolution
* is selected.
* NOTE: datasheet says that width (and height) should be filled with
* width-1. However, this doesn't work, since one pixel per line will
* be missing.
*/
hstart = 20 + (640 - core->width) / 2;
mt9v011_write(sd, R02_MT9V011_COLSTART, hstart);
mt9v011_write(sd, R04_MT9V011_WIDTH, core->width);
mt9v011_write(sd, R05_MT9V011_HBLANK, 771 - core->width);
vstart = 8 + (480 - core->height) / 2;
mt9v011_write(sd, R01_MT9V011_ROWSTART, vstart);
mt9v011_write(sd, R03_MT9V011_HEIGHT, core->height);
mt9v011_write(sd, R06_MT9V011_VBLANK, 508 - core->height);
calc_fps(sd, NULL, NULL);
};
static void set_read_mode(struct v4l2_subdev *sd)
{
struct mt9v011 *core = to_mt9v011(sd);
unsigned mode = 0x1000;
if (core->hflip)
mode |= 0x4000;
if (core->vflip)
mode |= 0x8000;
mt9v011_write(sd, R20_MT9V011_READ_MODE, mode);
}
static int mt9v011_reset(struct v4l2_subdev *sd, u32 val)
{
int i;
for (i = 0; i < ARRAY_SIZE(mt9v011_init_default); i++)
mt9v011_write(sd, mt9v011_init_default[i].reg,
mt9v011_init_default[i].value);
set_balance(sd);
set_res(sd);
set_read_mode(sd);
return 0;
};
static int mt9v011_g_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
{
struct mt9v011 *core = to_mt9v011(sd);
v4l2_dbg(1, debug, sd, "g_ctrl called\n");
switch (ctrl->id) {
case V4L2_CID_GAIN:
ctrl->value = core->global_gain;
return 0;
case V4L2_CID_EXPOSURE:
ctrl->value = core->exposure;
return 0;
case V4L2_CID_RED_BALANCE:
ctrl->value = core->red_bal;
return 0;
case V4L2_CID_BLUE_BALANCE:
ctrl->value = core->blue_bal;
return 0;
case V4L2_CID_HFLIP:
ctrl->value = core->hflip ? 1 : 0;
return 0;
case V4L2_CID_VFLIP:
ctrl->value = core->vflip ? 1 : 0;
return 0;
}
return -EINVAL;
}
static int mt9v011_queryctrl(struct v4l2_subdev *sd, struct v4l2_queryctrl *qc)
{
int i;
v4l2_dbg(1, debug, sd, "queryctrl called\n");
for (i = 0; i < ARRAY_SIZE(mt9v011_qctrl); i++)
if (qc->id && qc->id == mt9v011_qctrl[i].id) {
memcpy(qc, &(mt9v011_qctrl[i]),
sizeof(*qc));
return 0;
}
return -EINVAL;
}
static int mt9v011_s_ctrl(struct v4l2_subdev *sd, struct v4l2_control *ctrl)
{
struct mt9v011 *core = to_mt9v011(sd);
u8 i, n;
n = ARRAY_SIZE(mt9v011_qctrl);
for (i = 0; i < n; i++) {
if (ctrl->id != mt9v011_qctrl[i].id)
continue;
if (ctrl->value < mt9v011_qctrl[i].minimum ||
ctrl->value > mt9v011_qctrl[i].maximum)
return -ERANGE;
v4l2_dbg(1, debug, sd, "s_ctrl: id=%d, value=%d\n",
ctrl->id, ctrl->value);
break;
}
switch (ctrl->id) {
case V4L2_CID_GAIN:
core->global_gain = ctrl->value;
break;
case V4L2_CID_EXPOSURE:
core->exposure = ctrl->value;
break;
case V4L2_CID_RED_BALANCE:
core->red_bal = ctrl->value;
break;
case V4L2_CID_BLUE_BALANCE:
core->blue_bal = ctrl->value;
break;
case V4L2_CID_HFLIP:
core->hflip = ctrl->value;
set_read_mode(sd);
return 0;
case V4L2_CID_VFLIP:
core->vflip = ctrl->value;
set_read_mode(sd);
return 0;
default:
return -EINVAL;
}
set_balance(sd);
return 0;
}
static int mt9v011_enum_mbus_fmt(struct v4l2_subdev *sd, unsigned index,
enum v4l2_mbus_pixelcode *code)
{
if (index > 0)
return -EINVAL;
*code = V4L2_MBUS_FMT_SGRBG8_1X8;
return 0;
}
static int mt9v011_try_mbus_fmt(struct v4l2_subdev *sd, struct v4l2_mbus_framefmt *fmt)
{
if (fmt->code != V4L2_MBUS_FMT_SGRBG8_1X8)
return -EINVAL;
v4l_bound_align_image(&fmt->width, 48, 639, 1,
&fmt->height, 32, 480, 1, 0);
fmt->field = V4L2_FIELD_NONE;
fmt->colorspace = V4L2_COLORSPACE_SRGB;
return 0;
}
static int mt9v011_g_parm(struct v4l2_subdev *sd, struct v4l2_streamparm *parms)
{
struct v4l2_captureparm *cp = &parms->parm.capture;
if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
return -EINVAL;
memset(cp, 0, sizeof(struct v4l2_captureparm));
cp->capability = V4L2_CAP_TIMEPERFRAME;
calc_fps(sd,
&cp->timeperframe.numerator,
&cp->timeperframe.denominator);
return 0;
}
static int mt9v011_s_parm(struct v4l2_subdev *sd, struct v4l2_streamparm *parms)
{
struct v4l2_captureparm *cp = &parms->parm.capture;
struct v4l2_fract *tpf = &cp->timeperframe;
u16 speed;
if (parms->type != V4L2_BUF_TYPE_VIDEO_CAPTURE)
return -EINVAL;
if (cp->extendedmode != 0)
return -EINVAL;
speed = calc_speed(sd, tpf->numerator, tpf->denominator);
mt9v011_write(sd, R0A_MT9V011_CLK_SPEED, speed);
v4l2_dbg(1, debug, sd, "Setting speed to %d\n", speed);
/* Recalculate and update fps info */
calc_fps(sd, &tpf->numerator, &tpf->denominator);
return 0;
}
static int mt9v011_s_mbus_fmt(struct v4l2_subdev *sd, struct v4l2_mbus_framefmt *fmt)
{
struct mt9v011 *core = to_mt9v011(sd);
int rc;
rc = mt9v011_try_mbus_fmt(sd, fmt);
if (rc < 0)
return -EINVAL;
core->width = fmt->width;
core->height = fmt->height;
set_res(sd);
return 0;
}
#ifdef CONFIG_VIDEO_ADV_DEBUG
static int mt9v011_g_register(struct v4l2_subdev *sd,
struct v4l2_dbg_register *reg)
{
struct i2c_client *client = v4l2_get_subdevdata(sd);
if (!v4l2_chip_match_i2c_client(client, &reg->match))
return -EINVAL;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
reg->val = mt9v011_read(sd, reg->reg & 0xff);
reg->size = 2;
return 0;
}
static int mt9v011_s_register(struct v4l2_subdev *sd,
struct v4l2_dbg_register *reg)
{
struct i2c_client *client = v4l2_get_subdevdata(sd);
if (!v4l2_chip_match_i2c_client(client, &reg->match))
return -EINVAL;
if (!capable(CAP_SYS_ADMIN))
return -EPERM;
mt9v011_write(sd, reg->reg & 0xff, reg->val & 0xffff);
return 0;
}
#endif
static int mt9v011_g_chip_ident(struct v4l2_subdev *sd,
struct v4l2_dbg_chip_ident *chip)
{
u16 version;
struct i2c_client *client = v4l2_get_subdevdata(sd);
version = mt9v011_read(sd, R00_MT9V011_CHIP_VERSION);
return v4l2_chip_ident_i2c_client(client, chip, V4L2_IDENT_MT9V011,
version);
}
static const struct v4l2_subdev_core_ops mt9v011_core_ops = {
.queryctrl = mt9v011_queryctrl,
.g_ctrl = mt9v011_g_ctrl,
.s_ctrl = mt9v011_s_ctrl,
.reset = mt9v011_reset,
.g_chip_ident = mt9v011_g_chip_ident,
#ifdef CONFIG_VIDEO_ADV_DEBUG
.g_register = mt9v011_g_register,
.s_register = mt9v011_s_register,
#endif
};
static const struct v4l2_subdev_video_ops mt9v011_video_ops = {
.enum_mbus_fmt = mt9v011_enum_mbus_fmt,
.try_mbus_fmt = mt9v011_try_mbus_fmt,
.s_mbus_fmt = mt9v011_s_mbus_fmt,
.g_parm = mt9v011_g_parm,
.s_parm = mt9v011_s_parm,
};
static const struct v4l2_subdev_ops mt9v011_ops = {
.core = &mt9v011_core_ops,
.video = &mt9v011_video_ops,
};
/****************************************************************************
I2C Client & Driver
****************************************************************************/
static int mt9v011_probe(struct i2c_client *c,
const struct i2c_device_id *id)
{
u16 version;
struct mt9v011 *core;
struct v4l2_subdev *sd;
/* Check if the adapter supports the needed features */
if (!i2c_check_functionality(c->adapter,
I2C_FUNC_SMBUS_READ_BYTE | I2C_FUNC_SMBUS_WRITE_BYTE_DATA))
return -EIO;
core = kzalloc(sizeof(struct mt9v011), GFP_KERNEL);
if (!core)
return -ENOMEM;
sd = &core->sd;
v4l2_i2c_subdev_init(sd, c, &mt9v011_ops);
/* Check if the sensor is really a MT9V011 */
version = mt9v011_read(sd, R00_MT9V011_CHIP_VERSION);
if ((version != MT9V011_VERSION) &&
(version != MT9V011_REV_B_VERSION)) {
v4l2_info(sd, "*** unknown micron chip detected (0x%04x).\n",
version);
kfree(core);
return -EINVAL;
}
core->global_gain = 0x0024;
core->exposure = 0x01fc;
core->width = 640;
core->height = 480;
core->xtal = 27000000; /* Hz */
if (c->dev.platform_data) {
struct mt9v011_platform_data *pdata = c->dev.platform_data;
core->xtal = pdata->xtal;
v4l2_dbg(1, debug, sd, "xtal set to %d.%03d MHz\n",
core->xtal / 1000000, (core->xtal / 1000) % 1000);
}
v4l_info(c, "chip found @ 0x%02x (%s - chip version 0x%04x)\n",
c->addr << 1, c->adapter->name, version);
return 0;
}
static int mt9v011_remove(struct i2c_client *c)
{
struct v4l2_subdev *sd = i2c_get_clientdata(c);
v4l2_dbg(1, debug, sd,
"mt9v011.c: removing mt9v011 adapter on address 0x%x\n",
c->addr << 1);
v4l2_device_unregister_subdev(sd);
kfree(to_mt9v011(sd));
return 0;
}
/* ----------------------------------------------------------------------- */
static const struct i2c_device_id mt9v011_id[] = {
{ "mt9v011", 0 },
{ }
};
MODULE_DEVICE_TABLE(i2c, mt9v011_id);
static struct i2c_driver mt9v011_driver = {
.driver = {
.owner = THIS_MODULE,
.name = "mt9v011",
},
.probe = mt9v011_probe,
.remove = mt9v011_remove,
.id_table = mt9v011_id,
};
static __init int init_mt9v011(void)
{
return i2c_add_driver(&mt9v011_driver);
}
static __exit void exit_mt9v011(void)
{
i2c_del_driver(&mt9v011_driver);
}
module_init(init_mt9v011);
module_exit(exit_mt9v011);