[media] ov7670: allow configuration of image size, clock speed, and I/O method
These parameters need to be configurable based on the host system.
They can now be communicated through the s_config call.
The old CONFIG_OLPC_XO_1 selector was not correct; this kind of
arrangement wouldn't allow for a universal kernel that would work on both
laptops.
Certain parts of the probe routine had to be moved later (into s_config),
because we can't do any I/O until we know which I/O method has been
selected through this mechanism.
Signed-off-by: Daniel Drake <dsd@laptop.org>
Acked-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
diff --git a/drivers/media/video/ov7670.c b/drivers/media/video/ov7670.c
index 0b78f33..c881a64 100644
--- a/drivers/media/video/ov7670.c
+++ b/drivers/media/video/ov7670.c
@@ -20,6 +20,7 @@
#include <media/v4l2-chip-ident.h>
#include <media/v4l2-mediabus.h>
+#include "ov7670.h"
MODULE_AUTHOR("Jonathan Corbet <corbet@lwn.net>");
MODULE_DESCRIPTION("A low-level driver for OmniVision ov7670 sensors");
@@ -43,11 +44,6 @@
#define QCIF_HEIGHT 144
/*
- * Our nominal (default) frame rate.
- */
-#define OV7670_FRAME_RATE 30
-
-/*
* The 7670 sits on i2c with ID 0x42
*/
#define OV7670_I2C_ADDR 0x42
@@ -198,7 +194,11 @@
struct ov7670_format_struct *fmt; /* Current format */
unsigned char sat; /* Saturation value */
int hue; /* Hue value */
+ int min_width; /* Filter out smaller sizes */
+ int min_height; /* Filter out smaller sizes */
+ int clock_speed; /* External clock speed (MHz) */
u8 clkrc; /* Clock divider value */
+ bool use_smbus; /* Use smbus I/O instead of I2C */
};
static inline struct ov7670_info *to_state(struct v4l2_subdev *sd)
@@ -415,8 +415,7 @@
* ov7670 is not really an SMBUS device, though, so the communication
* is not always entirely reliable.
*/
-#ifdef CONFIG_OLPC_XO_1
-static int ov7670_read(struct v4l2_subdev *sd, unsigned char reg,
+static int ov7670_read_smbus(struct v4l2_subdev *sd, unsigned char reg,
unsigned char *value)
{
struct i2c_client *client = v4l2_get_subdevdata(sd);
@@ -431,7 +430,7 @@
}
-static int ov7670_write(struct v4l2_subdev *sd, unsigned char reg,
+static int ov7670_write_smbus(struct v4l2_subdev *sd, unsigned char reg,
unsigned char value)
{
struct i2c_client *client = v4l2_get_subdevdata(sd);
@@ -442,11 +441,10 @@
return ret;
}
-#else /* ! CONFIG_OLPC_XO_1 */
/*
* On most platforms, we'd rather do straight i2c I/O.
*/
-static int ov7670_read(struct v4l2_subdev *sd, unsigned char reg,
+static int ov7670_read_i2c(struct v4l2_subdev *sd, unsigned char reg,
unsigned char *value)
{
struct i2c_client *client = v4l2_get_subdevdata(sd);
@@ -479,7 +477,7 @@
}
-static int ov7670_write(struct v4l2_subdev *sd, unsigned char reg,
+static int ov7670_write_i2c(struct v4l2_subdev *sd, unsigned char reg,
unsigned char value)
{
struct i2c_client *client = v4l2_get_subdevdata(sd);
@@ -498,8 +496,26 @@
msleep(5); /* Wait for reset to run */
return ret;
}
-#endif /* CONFIG_OLPC_XO_1 */
+static int ov7670_read(struct v4l2_subdev *sd, unsigned char reg,
+ unsigned char *value)
+{
+ struct ov7670_info *info = to_state(sd);
+ if (info->use_smbus)
+ return ov7670_read_smbus(sd, reg, value);
+ else
+ return ov7670_read_i2c(sd, reg, value);
+}
+
+static int ov7670_write(struct v4l2_subdev *sd, unsigned char reg,
+ unsigned char value)
+{
+ struct ov7670_info *info = to_state(sd);
+ if (info->use_smbus)
+ return ov7670_write_smbus(sd, reg, value);
+ else
+ return ov7670_write_i2c(sd, reg, value);
+}
/*
* Write a list of register settings; ff/ff stops the process.
@@ -854,7 +870,7 @@
memset(cp, 0, sizeof(struct v4l2_captureparm));
cp->capability = V4L2_CAP_TIMEPERFRAME;
cp->timeperframe.numerator = 1;
- cp->timeperframe.denominator = OV7670_FRAME_RATE;
+ cp->timeperframe.denominator = info->clock_speed;
if ((info->clkrc & CLK_EXT) == 0 && (info->clkrc & CLK_SCALE) > 1)
cp->timeperframe.denominator /= (info->clkrc & CLK_SCALE);
return 0;
@@ -875,14 +891,14 @@
if (tpf->numerator == 0 || tpf->denominator == 0)
div = 1; /* Reset to full rate */
else
- div = (tpf->numerator*OV7670_FRAME_RATE)/tpf->denominator;
+ div = (tpf->numerator * info->clock_speed) / tpf->denominator;
if (div == 0)
div = 1;
else if (div > CLK_SCALE)
div = CLK_SCALE;
info->clkrc = (info->clkrc & 0x80) | div;
tpf->numerator = 1;
- tpf->denominator = OV7670_FRAME_RATE/div;
+ tpf->denominator = info->clock_speed / div;
return ov7670_write(sd, REG_CLKRC, info->clkrc);
}
@@ -912,14 +928,30 @@
static int ov7670_enum_framesizes(struct v4l2_subdev *sd,
struct v4l2_frmsizeenum *fsize)
{
+ struct ov7670_info *info = to_state(sd);
+ int i;
+ int num_valid = -1;
__u32 index = fsize->index;
- if (index >= N_WIN_SIZES)
- return -EINVAL;
- fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
- fsize->discrete.width = ov7670_win_sizes[index].width;
- fsize->discrete.height = ov7670_win_sizes[index].height;
- return 0;
+ /*
+ * If a minimum width/height was requested, filter out the capture
+ * windows that fall outside that.
+ */
+ for (i = 0; i < N_WIN_SIZES; i++) {
+ struct ov7670_win_size *win = &ov7670_win_sizes[index];
+ if (info->min_width && win->width < info->min_width)
+ continue;
+ if (info->min_height && win->height < info->min_height)
+ continue;
+ if (index == ++num_valid) {
+ fsize->type = V4L2_FRMSIZE_TYPE_DISCRETE;
+ fsize->discrete.width = win->width;
+ fsize->discrete.height = win->height;
+ return 0;
+ }
+ }
+
+ return -EINVAL;
}
/*
@@ -1417,6 +1449,47 @@
return v4l2_chip_ident_i2c_client(client, chip, V4L2_IDENT_OV7670, 0);
}
+static int ov7670_s_config(struct v4l2_subdev *sd, int dumb, void *data)
+{
+ struct i2c_client *client = v4l2_get_subdevdata(sd);
+ struct ov7670_config *config = data;
+ struct ov7670_info *info = to_state(sd);
+ int ret;
+
+ info->clock_speed = 30; /* default: a guess */
+
+ /*
+ * Must apply configuration before initializing device, because it
+ * selects I/O method.
+ */
+ if (config) {
+ info->min_width = config->min_width;
+ info->min_height = config->min_height;
+ info->use_smbus = config->use_smbus;
+
+ if (config->clock_speed)
+ info->clock_speed = config->clock_speed;
+ }
+
+ /* Make sure it's an ov7670 */
+ ret = ov7670_detect(sd);
+ if (ret) {
+ v4l_dbg(1, debug, client,
+ "chip found @ 0x%x (%s) is not an ov7670 chip.\n",
+ client->addr << 1, client->adapter->name);
+ kfree(info);
+ return ret;
+ }
+ v4l_info(client, "chip found @ 0x%02x (%s)\n",
+ client->addr << 1, client->adapter->name);
+
+ info->fmt = &ov7670_formats[0];
+ info->sat = 128; /* Review this */
+ info->clkrc = info->clock_speed / 30;
+
+ return 0;
+}
+
#ifdef CONFIG_VIDEO_ADV_DEBUG
static int ov7670_g_register(struct v4l2_subdev *sd, struct v4l2_dbg_register *reg)
{
@@ -1455,6 +1528,7 @@
.s_ctrl = ov7670_s_ctrl,
.queryctrl = ov7670_queryctrl,
.reset = ov7670_reset,
+ .s_config = ov7670_s_config,
.init = ov7670_init,
#ifdef CONFIG_VIDEO_ADV_DEBUG
.g_register = ov7670_g_register,
@@ -1484,7 +1558,6 @@
{
struct v4l2_subdev *sd;
struct ov7670_info *info;
- int ret;
info = kzalloc(sizeof(struct ov7670_info), GFP_KERNEL);
if (info == NULL)
@@ -1492,22 +1565,6 @@
sd = &info->sd;
v4l2_i2c_subdev_init(sd, client, &ov7670_ops);
- /* Make sure it's an ov7670 */
- ret = ov7670_detect(sd);
- if (ret) {
- v4l_dbg(1, debug, client,
- "chip found @ 0x%x (%s) is not an ov7670 chip.\n",
- client->addr << 1, client->adapter->name);
- kfree(info);
- return ret;
- }
- v4l_info(client, "chip found @ 0x%02x (%s)\n",
- client->addr << 1, client->adapter->name);
-
- info->fmt = &ov7670_formats[0];
- info->sat = 128; /* Review this */
- info->clkrc = 1; /* 30fps */
-
return 0;
}