Re: [PATCH 01/10] staging: media: go7007: Some additional code for TW2804 driver functionality

From: Hans Verkuil
Date: Wed Aug 22 2012 - 04:03:06 EST


Hi Volokh!

Thanks for working on this!

I have some quick review notes below.

On Wed August 22 2012 12:45:10 Volokh Konstantin wrote:
> - using new v4l2 framework controls
> - function for reading volatile controls via i2c bus
> - separate V4L2_CID_ ctrls into each V4L2 calls
>
> Signed-off-by: Volokh Konstantin <volokh84@xxxxxxxxx>
> ---
> drivers/staging/media/go7007/wis-tw2804.c | 248 +++++++++++++++++++++++++++++
> 1 files changed, 248 insertions(+), 0 deletions(-)
>
> diff --git a/drivers/staging/media/go7007/wis-tw2804.c b/drivers/staging/media/go7007/wis-tw2804.c
> index 9134f03..05851d3 100644
> --- a/drivers/staging/media/go7007/wis-tw2804.c
> +++ b/drivers/staging/media/go7007/wis-tw2804.c
> @@ -21,10 +21,18 @@
> #include <linux/videodev2.h>
> #include <linux/ioctl.h>
> #include <linux/slab.h>
> +#include <media/v4l2-subdev.h>
> +#include <media/v4l2-device.h>
> +#include <media/v4l2-chip-ident.h>
> +#include <media/v4l2-ctrls.h>
>
> #include "wis-i2c.h"
>
> struct wis_tw2804 {
> + struct v4l2_subdev sd;
> + struct v4l2_ctrl_handler hdl;
> + u8 channel:2;
> + u8 input:1;
> int channel;
> int norm;
> int brightness;
> @@ -116,9 +124,246 @@ static int write_regs(struct i2c_client *client, u8 *regs, int channel)
> if (i2c_smbus_write_byte_data(client,
> regs[i] | (channel << 6), regs[i + 1]) < 0)
> return -1;
> +static s32 read_reg(struct i2c_client *client, u8 reg, u8 channel)
> +{
> + return i2c_smbus_read_byte_data(client, (reg) | (channel << 6));
> +}
> +
> +inline struct wis_tw2804 *to_state(struct v4l2_subdev *sd)
> +{
> + return container_of(sd, struct wis_tw2804, sd);
> +}
> +
> +inline struct wis_tw2804 *to_state_from_ctrl(struct v4l2_ctrl *ctrl)
> +{
> + return container_of(ctrl->handler, struct wis_tw2804, hdl);
> +}
> +
> +static int tw2804_log_status(struct v4l2_subdev *sd)
> +{
> + struct wis_tw2804 *state = to_state(sd);
> + v4l2_info(sd, "Standard: %s\n",
> + state->norm == V4L2_STD_NTSC ? "NTSC" :
> + state->norm == V4L2_STD_PAL ? "PAL" : "unknown");
> + v4l2_info(sd, "Channel: %d\n", state->channel);
> + v4l2_info(sd, "Input: %d\n", state->input);
> + v4l2_ctrl_handler_log_status(&state->hdl, sd->name);
> + return 0;
> +}
> +
> +static s32 get_ctrl_addr(int ctrl)
> +{
> + switch (ctrl) {
> + case V4L2_CID_BRIGHTNESS:
> + return 0x12;
> + case V4L2_CID_CONTRAST:
> + return 0x11;
> + case V4L2_CID_SATURATION:
> + return 0x10;
> + case V4L2_CID_HUE:
> + return 0x0f;
> + case V4L2_CID_AUTOGAIN:
> + return 0x02;
> + case V4L2_CID_COLOR_KILLER:
> + return 0x14;
> + case V4L2_CID_GAIN:
> + return 0x3c;
> + case V4L2_CID_CHROMA_GAIN:
> + return 0x3d;
> + case V4L2_CID_RED_BALANCE:
> + return 0x3f;
> + case V4L2_CID_BLUE_BALANCE:
> + return 0x3e;
> + default:
> + return -EINVAL;
> + }
> +}
> +
> +static int tw2804_g_volatile_ctrl(struct v4l2_ctrl *ctrl)
> +{
> + struct v4l2_subdev *sd = &to_state_from_ctrl(ctrl)->sd;
> + struct i2c_client *client = v4l2_get_subdevdata(sd);
> + s32 addr = get_ctrl_addr(ctrl->id);
> +
> + if (addr == -EINVAL)
> + return -EINVAL;
> +
> + switch (ctrl->id) {
> + case V4L2_CID_GAIN:
> + case V4L2_CID_CHROMA_GAIN:
> + case V4L2_CID_RED_BALANCE:
> + case V4L2_CID_BLUE_BALANCE:
> + ctrl->cur.val = read_reg(client, addr, 0);

That should be ctrl->val, not ctrl->cur.val.

> + break;
> + default:
> + return -EINVAL;
> + }
> + return 0;
> +}
> +
> +static int tw2804_s_ctrl(struct v4l2_ctrl *ctrl)
> +{
> + struct wis_tw2804 *state = to_state_from_ctrl(ctrl);
> + struct v4l2_subdev *sd = &state->sd;
> + struct i2c_client *client = v4l2_get_subdevdata(sd);
> + s32 reg = ctrl->val;
> + s32 addr = get_ctrl_addr(ctrl->id);
> +
> + if (addr == -EINVAL)
> + return -EINVAL;
> +
> + switch (ctrl->id) {
> + case V4L2_CID_AUTOGAIN:
> + reg = read_reg(client, addr, state->channel);
> + if (reg > 0) {
> + if (ctrl->val == 0)
> + reg &= ~(1<<7);
> + else
> + reg |= 1<<7;
> + } else
> + return reg;
> + break;
> + case V4L2_CID_COLOR_KILLER:
> + reg = read_reg(client, addr, state->channel);
> + if (reg > 0)
> + reg = (reg & ~(0x03)) | (ctrl->val == 0 ? 0x02 : 0x03);
> + else
> + return reg;
> + break;
> + default:
> + break;
> + }
> +
> + reg = reg > 255 ? 255 : (reg < 0 ? 0 : reg);
> + reg = write_reg(client, addr, (u8)reg,
> + ctrl->id == V4L2_CID_GAIN ||
> + ctrl->id == V4L2_CID_CHROMA_GAIN ||
> + ctrl->id == V4L2_CID_RED_BALANCE ||
> + ctrl->id == V4L2_CID_BLUE_BALANCE ? 0 : state->channel);
> +
> + if (reg < 0) {
> + v4l2_err(sd, "Can`t set_ctrl value:id=%d;value=%d\n", ctrl->id,
> + ctrl->val);
> + return reg;
> + }
> + return 0;
> +}
> +
> +static int tw2804_s_std(struct v4l2_subdev *sd, v4l2_std_id norm)
> +{
> + struct wis_tw2804 *dec = to_state(sd);
> + struct i2c_client *client = v4l2_get_subdevdata(sd);
> +
> + u8 regs[] = {
> + 0x01, norm&V4L2_STD_NTSC ? 0xc4 : 0x84,

I recommend creating a bool variable storing the result of norm & V4L2_STD_NTSC
rather than repeating it.

Also, do you really mean 'norm & V4L2_STD_NTSC', or do you mean
'norm & V4L2_STD_525_60'?

My guess is the latter.

> + 0x09, norm&V4L2_STD_NTSC ? 0x07 : 0x04,
> + 0x0a, norm&V4L2_STD_NTSC ? 0xf0 : 0x20,
> + 0x0b, norm&V4L2_STD_NTSC ? 0x07 : 0x04,
> + 0x0c, norm&V4L2_STD_NTSC ? 0xf0 : 0x20,
> + 0x0d, norm&V4L2_STD_NTSC ? 0x40 : 0x4a,
> + 0x16, norm&V4L2_STD_NTSC ? 0x00 : 0x40,
> + 0x17, norm&V4L2_STD_NTSC ? 0x00 : 0x40,
> + 0x20, norm&V4L2_STD_NTSC ? 0x07 : 0x0f,
> + 0x21, norm&V4L2_STD_NTSC ? 0x07 : 0x0f,
> + 0xff, 0xff,
> + };
> + write_regs(client, regs, dec->channel);
> + dec->norm = norm;
> + return 0;
> +}
> +
> +static int tw2804_g_chip_ident(struct v4l2_subdev *sd,
> + struct v4l2_dbg_chip_ident *chip)
> +{
> + struct i2c_client *client = v4l2_get_subdevdata(sd);
> + return v4l2_chip_ident_i2c_client(client, chip,
> + V4L2_IDENT_TW2804, 0x0e);
> +}
> +
> +static const struct v4l2_ctrl_ops tw2804_ctrl_ops = {
> + .g_volatile_ctrl = tw2804_g_volatile_ctrl,
> + .s_ctrl = tw2804_s_ctrl,
> +};
> +
> +static const struct v4l2_subdev_core_ops tw2804_core_ops = {
> + .log_status = tw2804_log_status,
> + .g_chip_ident = tw2804_g_chip_ident,
> + .g_ext_ctrls = v4l2_subdev_g_ext_ctrls,
> + .try_ext_ctrls = v4l2_subdev_try_ext_ctrls,
> + .s_ext_ctrls = v4l2_subdev_s_ext_ctrls,
> + .g_ctrl = v4l2_subdev_g_ctrl,
> + .s_ctrl = v4l2_subdev_s_ctrl,
> + .queryctrl = v4l2_subdev_queryctrl,
> + .querymenu = v4l2_subdev_querymenu,
> + .s_std = tw2804_s_std,
> +};
> +
> +static int tw2804_s_video_routing(struct v4l2_subdev *sd, u32 input, u32 output,
> + u32 config)
> +{
> + struct wis_tw2804 *dec = to_state(sd);
> + struct i2c_client *client = v4l2_get_subdevdata(sd);
> + s32 reg = 0;
> +
> + if (0 > input || input > 1)
> + return -EINVAL;
> +
> + if (input == dec->input)
> + return 0;
> +
> + reg = read_reg(client, 0x22, dec->channel);
> +
> + if (reg >= 0) {
> + if (input == 0)
> + reg &= ~(1<<2);
> + else
> + reg |= 1<<2;
> + reg = write_reg(client, 0x22, (u8)reg, dec->channel);
> + }
> +
> + if (reg >= 0)
> + dec->input = input;
> + else
> + return reg;
> return 0;
> }
>
> +static int tw2804_s_mbus_fmt(struct v4l2_subdev *sd,
> + struct v4l2_mbus_framefmt *fmt)
> +{
> + /*TODO need select between 3fmt:
> + * bt_656,
> + * bt_601_8bit,
> + * bt_656_dual,
> + */
> + return 0;
> +}
> +
> +static int tw2804_s_stream(struct v4l2_subdev *sd, int enable)
> +{
> + struct wis_tw2804 *dec = to_state(sd);
> + struct i2c_client *client = v4l2_get_subdevdata(sd);
> + u32 reg = read_reg(client, 0x78, 0);
> +
> + if (enable == 1)
> + write_reg(client, 0x78, reg & ~(1<<dec->channel), 0);
> + else
> + write_reg(client, 0x78, reg | (1<<dec->channel), 0);
> +
> + return 0;
> +}
> +
> +static const struct v4l2_subdev_video_ops tw2804_video_ops = {
> + .s_routing = tw2804_s_video_routing,
> + .s_mbus_fmt = tw2804_s_mbus_fmt,
> + .s_stream = tw2804_s_stream,
> +};
> +
> +static const struct v4l2_subdev_ops tw2804_ops = {
> + .core = &tw2804_core_ops,
> + .video = &tw2804_video_ops,
> +};
> +
> static int wis_tw2804_command(struct i2c_client *client,
> unsigned int cmd, void *arg)
> {
> @@ -355,3 +600,6 @@ module_init(wis_tw2804_init);
> module_exit(wis_tw2804_cleanup);
>
> MODULE_LICENSE("GPL v2");
> +MODULE_DESCRIPTION("TW2804/TW2802 V4L2 i2c driver");
> +MODULE_AUTHOR("Volokh Konstantin <volokh84@xxxxxxxxx>");
> +MODULE_AUTHOR("Micronas USA Inc");
>

Regards,

Hans
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/