From 75e2bdad8901a0b599e01a96229be922eef1e488 Mon Sep 17 00:00:00 2001 From: Daniel Drake Date: Tue, 19 Oct 2010 18:24:05 -0300 Subject: [PATCH] [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 Acked-by: Jonathan Corbet Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/ov7670.c | 133 +++++++++++++++++++++++++---------- drivers/media/video/ov7670.h | 20 ++++++ 2 files changed, 115 insertions(+), 38 deletions(-) create mode 100644 drivers/media/video/ov7670.h diff --git a/drivers/media/video/ov7670.c b/drivers/media/video/ov7670.c index 0b78f33a69b4..c881a64b41fd 100644 --- a/drivers/media/video/ov7670.c +++ b/drivers/media/video/ov7670.c @@ -20,6 +20,7 @@ #include #include +#include "ov7670.h" MODULE_AUTHOR("Jonathan Corbet "); MODULE_DESCRIPTION("A low-level driver for OmniVision ov7670 sensors"); @@ -42,11 +43,6 @@ MODULE_PARM_DESC(debug, "Debug level (0-1)"); #define QCIF_WIDTH 176 #define QCIF_HEIGHT 144 -/* - * Our nominal (default) frame rate. - */ -#define OV7670_FRAME_RATE 30 - /* * The 7670 sits on i2c with ID 0x42 */ @@ -198,7 +194,11 @@ struct ov7670_info { 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 @@ static struct regval_list ov7670_fmt_raw[] = { * 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_read(struct v4l2_subdev *sd, unsigned char reg, } -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 @@ static int ov7670_write(struct v4l2_subdev *sd, unsigned char reg, 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_read(struct v4l2_subdev *sd, unsigned char reg, } -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 @@ static int ov7670_write(struct v4l2_subdev *sd, unsigned char reg, 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 @@ static int ov7670_g_parm(struct v4l2_subdev *sd, struct v4l2_streamparm *parms) 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 @@ static int ov7670_s_parm(struct v4l2_subdev *sd, struct v4l2_streamparm *parms) 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_frameintervals(struct v4l2_subdev *sd, 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 @@ static int ov7670_g_chip_ident(struct v4l2_subdev *sd, 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 @@ static const struct v4l2_subdev_core_ops ov7670_core_ops = { .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 @@ static int ov7670_probe(struct i2c_client *client, { 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 @@ static int ov7670_probe(struct i2c_client *client, 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; } diff --git a/drivers/media/video/ov7670.h b/drivers/media/video/ov7670.h new file mode 100644 index 000000000000..b133bc123031 --- /dev/null +++ b/drivers/media/video/ov7670.h @@ -0,0 +1,20 @@ +/* + * A V4L2 driver for OmniVision OV7670 cameras. + * + * Copyright 2010 One Laptop Per Child + * + * This file may be distributed under the terms of the GNU General + * Public License, version 2. + */ + +#ifndef __OV7670_H +#define __OV7670_H + +struct ov7670_config { + int min_width; /* Filter out smaller sizes */ + int min_height; /* Filter out smaller sizes */ + int clock_speed; /* External clock speed (MHz) */ + bool use_smbus; /* Use smbus I/O instead of I2C */ +}; + +#endif -- 2.34.1