On Thursday 11 December 2008 21:38:28 Aguirre Rodriguez, Sergio Alberto wrote:
> >From 1341b74f5a90e4aa079a4fcb4fe2127ff344cce7 Mon Sep 17 00:00:00 2001
> From: Sergio Aguirre <[email protected]>
> Date: Thu, 11 Dec 2008 13:35:46 -0600
> Subject: [PATCH] OMAP: CAM: Add Lens Driver
>
> This adds the DW9710 Lens driver
>
> Signed-off-by: Sergio Aguirre <[email protected]>
> ---
> drivers/media/video/Kconfig | 8 +
> drivers/media/video/Makefile | 1 +
> drivers/media/video/dw9710.c | 569
> ++++++++++++++++++++++++++++++++++++++++++
> drivers/media/video/dw9710.h | 59 +++++
> 4 files changed, 637 insertions(+), 0 deletions(-)
> create mode 100644 drivers/media/video/dw9710.c
> create mode 100644 drivers/media/video/dw9710.h
>
> diff --git a/drivers/media/video/Kconfig b/drivers/media/video/Kconfig
> index 24957bc..50651f2 100644
> --- a/drivers/media/video/Kconfig
> +++ b/drivers/media/video/Kconfig
> @@ -313,6 +313,14 @@ config VIDEO_MT9P012
> MT9P012 camera. It is currently working with the TI OMAP3
> camera controller.
>
> +config VIDEO_DW9710
> + tristate "Lens driver for DW9710"
> + depends on I2C && VIDEO_V4L2
> + ---help---
> + This is a Video4Linux2 lens driver for the Dongwoon
> + DW9710 coil. It is currently working with the TI OMAP3
> + camera controller and micron MT9P012 sensor.
> +
> config VIDEO_SAA7110
> tristate "Philips SAA7110 video decoder"
> depends on VIDEO_V4L1 && I2C
> diff --git a/drivers/media/video/Makefile b/drivers/media/video/Makefile
> index f73b65c..41c71d5 100644
> --- a/drivers/media/video/Makefile
> +++ b/drivers/media/video/Makefile
> @@ -101,6 +101,7 @@ obj-$(CONFIG_VIDEO_OV7670) += ov7670.o
>
> obj-$(CONFIG_VIDEO_TCM825X) += tcm825x.o
> obj-$(CONFIG_VIDEO_MT9P012) += mt9p012.o
> +obj-$(CONFIG_VIDEO_DW9710) += dw9710.o
>
> obj-$(CONFIG_VIDEO_OMAP3) += omap34xxcam.o isp/
>
> diff --git a/drivers/media/video/dw9710.c b/drivers/media/video/dw9710.c
> new file mode 100644
> index 0000000..b5d5247
> --- /dev/null
> +++ b/drivers/media/video/dw9710.c
> @@ -0,0 +1,569 @@
> +/*
> + * drivers/media/video/dw9710.c
> + *
> + * DW9710 Coil Motor (LENS) driver
> + *
> + * Copyright (C) 2008 Texas Instruments.
> + *
> + * Contributors:
> + * Troy Laramy <[email protected]>
> + * Mohit Jalori <[email protected]>
> + *
> + * This file is licensed under the terms of the GNU General Public License
> + * version 2. This program is licensed "as is" without any warranty of any
> + * kind, whether express or implied.
> + *
> + */
> +
> +#include <linux/mutex.h>
> +#include <linux/i2c.h>
> +#include <linux/delay.h>
> +#include <media/v4l2-int-device.h>
> +#include <mach/gpio.h>
> +#include <linux/platform_device.h>
> +#include <linux/cdev.h>
> +#include <linux/device.h>
> +
> +#include "dw9710.h"
> +
> +#define DRIVER_NAME "dw9710"
> +
> +static int
> +dw9710_probe(struct i2c_client *client, const struct i2c_device_id *id);
> +static int __exit dw9710_remove(struct i2c_client *client);
> +
> +struct dw9710_device {
> + const struct dw9710_platform_data *pdata;
> + struct v4l2_int_device *v4l2_int_device;
> + struct i2c_client *i2c_client;
> + int opened;
> + u16 current_lens_posn;
> + u16 saved_lens_posn;
> + int state;
> + int power_state;
> +};
> +
> +static const struct i2c_device_id dw9710_id[] = {
> + { DW9710_NAME, 0 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(i2c, dw9710_id);
> +
> +static struct i2c_driver dw9710_i2c_driver = {
> + .driver = {
> + .name = DW9710_NAME,
> + .owner = THIS_MODULE,
> + },
> + .probe = dw9710_probe,
> + .remove = __exit_p(dw9710_remove),
> + .id_table = dw9710_id,
> +};
> +
> +static struct dw9710_device dw9710 = {
> + .state = LENS_NOT_DETECTED,
> + .current_lens_posn = DEF_LENS_POSN,
> +};
> +
> +static struct vcontrol {
> + struct v4l2_queryctrl qc;
> + int current_value;
> +} video_control[] = {
> + {
> + {
> + .id = V4L2_CID_FOCUS_ABSOLUTE,
> + .type = V4L2_CTRL_TYPE_INTEGER,
> + .name = "Lens Position",
Please use the standard string for this: "Focus, Absolute".
> + .minimum = 0,
> + .maximum = MAX_FOCUS_POS,
> + .step = LENS_POSN_STEP,
> + .default_value = DEF_LENS_POSN,
> + },
> + .current_value = DEF_LENS_POSN,
> + }
> +};
> +
> +static struct i2c_driver dw9710_i2c_driver;
> +
> +/**
> + * find_vctrl - Finds the requested ID in the video control structure array
> + * @id: ID of control to search the video control array for
> + *
> + * Returns the index of the requested ID from the control structure array
> + */
> +static int
> +find_vctrl(int id)
> +{
> + int i;
> +
> + if (id < V4L2_CID_BASE)
> + return -EDOM;
> +
> + for (i = (ARRAY_SIZE(video_control) - 1); i >= 0; i--)
> + if (video_control[i].qc.id == id)
> + break;
> + if (i < 0)
> + i = -EINVAL;
> + return i;
> +}
> +
> +/**
> + * camaf_reg_read - Reads a value from a register in DW9710 Coil driver
> device.
> + * @client: Pointer to structure of I2C client.
> + * @value: Pointer to u16 for returning value of register to read.
> + *
> + * Returns zero if successful, or non-zero otherwise.
> + **/
> +static int camaf_reg_read(struct i2c_client *client, u16 *value)
> +{
> + int err;
> + struct i2c_msg msg[1];
> + unsigned char data[2];
> +
> + if (!client->adapter)
> + return -ENODEV;
> +
> + msg->addr = client->addr;
> + msg->flags = I2C_M_RD;
> + msg->len = 2;
> + msg->buf = data;
> +
> + data[0] = 0;
> + data[1] = 0;
> +
> + err = i2c_transfer(client->adapter, msg, 1);
> +
> + if (err >= 0) {
> + *value = err = ((data[0] & 0xFF) << 8) | (data[1]);
> + return 0;
> + }
> + return err;
> +}
> +
> +/**
> + * camaf_reg_write - Writes a value to a register in DW9710 Coil driver
> device.
> + * @client: Pointer to structure of I2C client.
> + * @value: Value of register to write.
> + *
> + * Returns zero if successful, or non-zero otherwise.
> + **/
> +static int camaf_reg_write(struct i2c_client *client, u16 value)
> +{
> + int err;
> + struct i2c_msg msg[1];
> + unsigned char data[2];
> + int retry = 0;
> +
> + if (!client->adapter)
> + return -ENODEV;
> +
> +again:
> + msg->addr = client->addr;
> + msg->flags = 0;
> + msg->len = 2;
> + msg->buf = data;
> +
> + data[0] = (u8)(value >> 8);
> + data[1] = (u8)(value & 0xFF);
> +
> + err = i2c_transfer(client->adapter, msg, 1);
> +
> + if (err >= 0)
> + return 0;
> +
> + if (retry <= DW9710_I2C_RETRY_COUNT) {
> + dev_dbg(&client->dev, "retry ... %d", retry);
> + retry++;
> + set_current_state(TASK_UNINTERRUPTIBLE);
> + schedule_timeout(msecs_to_jiffies(20));
> + goto again;
> + }
> + return err;
> +}
> +
> +/**
> + * dw9710_detect - Detects DW9710 Coil driver device.
> + * @client: Pointer to structure of I2C client.
> + *
> + * Returns 0 if successful, -1 if camera is off or if test register value
> + * wasn't stored properly, or returned errors from either camaf_reg_write or
> + * camaf_reg_read functions.
> + **/
> +static int dw9710_detect(struct i2c_client *client)
> +{
> + int err = 0;
> + u16 wposn = 0, rposn = 0;
> + u16 posn = 0x05;
> +
> + wposn = (CAMAF_DW9710_POWERDN(CAMAF_DW9710_ENABLE) |
> + CAMAF_DW9710_DATA(posn));
> +
> + err = camaf_reg_write(client, wposn);
> + if (err) {
> + printk(KERN_ERR "Unable to write DW9710 \n");
> + return err;
> + }
> +
> + err = camaf_reg_read(client, &rposn);
> + if (err) {
> + printk(KERN_ERR "Unable to read DW9710 \n");
> + return err;
> + }
> +
> + if (wposn != rposn) {
> + printk(KERN_ERR "W/R MISMATCH!\n");
> + return -1;
> + }
> + posn = 0;
> + wposn = (CAMAF_DW9710_POWERDN(CAMAF_DW9710_ENABLE) |
> + CAMAF_DW9710_DATA(posn));
> + err = camaf_reg_write(client, wposn);
> +
> + return err;
> +}
> +
> +/**
> + * dw9710_af_setfocus - Sets the desired focus.
> + * @posn: Desired focus position, 0 (far) - 100 (close).
> + *
> + * Returns 0 on success, -EINVAL if camera is off or focus value is out of
> + * bounds, or returned errors from either camaf_reg_write or camaf_reg_read
> + * functions.
> + **/
> +int dw9710_af_setfocus(u16 posn)
> +{
> + struct dw9710_device *af_dev = &dw9710;
> + struct i2c_client *client = af_dev->i2c_client;
> + u16 cur_focus_value = 0;
> + int ret = -EINVAL;
> +
> + if (posn > MAX_FOCUS_POS) {
> + printk(KERN_ERR "Bad posn params 0x%x \n", posn);
> + return ret;
> + }
> +
> + if ((af_dev->power_state == V4L2_POWER_OFF) ||
> + (af_dev->power_state == V4L2_POWER_STANDBY)) {
> + af_dev->current_lens_posn = posn;
> + return 0;
> + }
> +
> + ret = camaf_reg_read(client, &cur_focus_value);
> +
> + if (ret) {
> + printk(KERN_ERR "Read of current Lens position failed\n");
> + return ret;
> + }
> +
> + if (CAMAF_DW9710_DATA_R(cur_focus_value) == posn) {
> + printk(KERN_DEBUG "Device already in requested focal
> point\n");
> + return ret;
> + }
> +
> + ret = camaf_reg_write(client,
> + CAMAF_DW9710_POWERDN(CAMAF_DW9710_ENABLE) |
> + CAMAF_DW9710_DATA(posn));
> +
> + if (ret)
> + printk(KERN_ERR "Setfocus register write failed\n");
> + dw9710.current_lens_posn = posn;
> + return ret;
> +}
> +EXPORT_SYMBOL(dw9710_af_setfocus);
> +
> +/**
> + * dw9710_af_getfocus - Gets the focus value from device.
> + * @value: Pointer to u16 variable which will contain the focus value.
> + *
> + * Returns 0 if successful, -EINVAL if camera is off, or return value of
> + * camaf_reg_read if fails.
> + **/
> +int dw9710_af_getfocus(u16 *value)
> +{
> + int ret = -EINVAL;
> + u16 posn = 0;
> +
> + struct dw9710_device *af_dev = &dw9710;
> + struct i2c_client *client = af_dev->i2c_client;
> +
> + if ((af_dev->power_state == V4L2_POWER_OFF) ||
> + (af_dev->power_state == V4L2_POWER_STANDBY))
> + return ret;
> +
> + ret = camaf_reg_read(client, &posn);
> +
> + if (ret) {
> + printk(KERN_ERR "Read of current Lens position failed\n");
> + return ret;
> + }
> + *value = CAMAF_DW9710_DATA_R(posn);
> + dw9710.current_lens_posn = CAMAF_DW9710_DATA_R(posn);
> + return ret;
> +}
> +EXPORT_SYMBOL(dw9710_af_getfocus);
> +
> +/**
> + * ioctl_queryctrl - V4L2 lens interface handler for VIDIOC_QUERYCTRL ioctl
> + * @s: pointer to standard V4L2 device structure
> + * @qc: standard V4L2 VIDIOC_QUERYCTRL ioctl structure
> + *
> + * If the requested control is supported, returns the control information
> + * from the video_control[] array. Otherwise, returns -EINVAL if the
> + * control is not supported.
> + */
> +static int ioctl_queryctrl(struct v4l2_int_device *s,
> + struct v4l2_queryctrl *qc)
> +{
> + int i;
> +
> + i = find_vctrl(qc->id);
> + if (i == -EINVAL)
> + qc->flags = V4L2_CTRL_FLAG_DISABLED;
> +
> + if (i < 0)
> + return -EINVAL;
> +
> + *qc = video_control[i].qc;
> + return 0;
> +}
> +
> +/**
> + * ioctl_g_ctrl - V4L2 DW9710 lens interface handler for VIDIOC_G_CTRL ioctl
> + * @s: pointer to standard V4L2 device structure
> + * @vc: standard V4L2 VIDIOC_G_CTRL ioctl structure
> + *
> + * If the requested control is supported, returns the control's current
> + * value from the video_control[] array. Otherwise, returns -EINVAL
> + * if the control is not supported.
> + */
> +static int ioctl_g_ctrl(struct v4l2_int_device *s,
> + struct v4l2_control *vc)
> +{
> + struct vcontrol *lvc;
> + int i;
> + u16 curr_posn;
> +
> + i = find_vctrl(vc->id);
> + if (i < 0)
> + return -EINVAL;
> + lvc = &video_control[i];
> +
> + switch (vc->id) {
> + case V4L2_CID_FOCUS_ABSOLUTE:
> + if (dw9710_af_getfocus(&curr_posn))
> + return -EFAULT;
> + vc->value = curr_posn;
> + lvc->current_value = curr_posn;
> + break;
> + }
> +
> + return 0;
> +}
> +
> +/**
> + * ioctl_s_ctrl - V4L2 DW9710 lens interface handler for VIDIOC_S_CTRL ioctl
> + * @s: pointer to standard V4L2 device structure
> + * @vc: standard V4L2 VIDIOC_S_CTRL ioctl structure
> + *
> + * If the requested control is supported, sets the control's current
> + * value in HW (and updates the video_control[] array). Otherwise,
> + * returns -EINVAL if the control is not supported.
> + */
> +static int ioctl_s_ctrl(struct v4l2_int_device *s,
> + struct v4l2_control *vc)
> +{
> + int retval = -EINVAL;
> + int i;
> + struct vcontrol *lvc;
> +
> + i = find_vctrl(vc->id);
> + if (i < 0)
> + return -EINVAL;
> + lvc = &video_control[i];
> +
> + switch (vc->id) {
> + case V4L2_CID_FOCUS_ABSOLUTE:
> + retval = dw9710_af_setfocus(vc->value);
> + if (!retval)
> + lvc->current_value = vc->value;
> + break;
> + }
> +
> + return retval;
> +}
> +
> +/**
> + * ioctl_g_priv - V4L2 sensor interface handler for vidioc_int_g_priv_num
> + * @s: pointer to standard V4L2 device structure
> + * @p: void pointer to hold sensor's private data address
> + *
> + * Returns device's (sensor's) private data area address in p parameter
> + */
> +static int ioctl_g_priv(struct v4l2_int_device *s, void *p)
> +{
> + struct dw9710_device *lens = s->priv;
> +
> + return lens->pdata->priv_data_set(p);
> +
> +}
> +
> +/**
> + * ioctl_s_power - V4L2 sensor interface handler for vidioc_int_s_power_num
> + * @s: pointer to standard V4L2 device structure
> + * @on: power state to which device is to be set
> + *
> + * Sets devices power state to requrested state, if possible.
> + */
> +static int ioctl_s_power(struct v4l2_int_device *s, enum v4l2_power on)
> +{
> + struct dw9710_device *lens = s->priv;
> + struct i2c_client *c = lens->i2c_client;
> + int rval;
> +
> + rval = lens->pdata->power_set(on);
> + if (rval < 0) {
> + dev_err(&c->dev, "Unable to set the power state: " DRIVER_NAME
> + " lens HW\n");
> + return rval;
> + }
> +
> + if ((on == V4L2_POWER_ON) && (lens->state == LENS_NOT_DETECTED)) {
> + rval = dw9710_detect(c);
> + if (rval < 0) {
> + dev_err(&c->dev, "Unable to detect "
> + DRIVER_NAME " lens HW\n");
> + printk(KERN_ERR "Unable to detect "
> + DRIVER_NAME " lens HW\n");
> + lens->state = LENS_NOT_DETECTED;
> + return rval;
> + }
> + lens->state = LENS_DETECTED;
> + pr_info(DRIVER_NAME " lens HW detected\n");
> + }
> +
> + if ((lens->power_state == V4L2_POWER_STANDBY) && (on == V4L2_POWER_ON)
> + && (lens->state == LENS_DETECTED))
> + dw9710_af_setfocus(lens->current_lens_posn);
> +
> + lens->power_state = on;
> + return 0;
> +}
> +
> +static struct v4l2_int_ioctl_desc dw9710_ioctl_desc[] = {
> + { .num = vidioc_int_s_power_num,
> + .func = (v4l2_int_ioctl_func *)ioctl_s_power },
> + { .num = vidioc_int_g_priv_num,
> + .func = (v4l2_int_ioctl_func *)ioctl_g_priv },
> + { .num = vidioc_int_queryctrl_num,
> + .func = (v4l2_int_ioctl_func *)ioctl_queryctrl },
> + { .num = vidioc_int_g_ctrl_num,
> + .func = (v4l2_int_ioctl_func *)ioctl_g_ctrl },
> + { .num = vidioc_int_s_ctrl_num,
> + .func = (v4l2_int_ioctl_func *)ioctl_s_ctrl },
> +};
> +
> +static struct v4l2_int_slave dw9710_slave = {
> + .ioctls = dw9710_ioctl_desc,
> + .num_ioctls = ARRAY_SIZE(dw9710_ioctl_desc),
> +};
> +
> +static struct v4l2_int_device dw9710_int_device = {
> + .module = THIS_MODULE,
> + .name = DRIVER_NAME,
> + .priv = &dw9710,
> + .type = v4l2_int_type_slave,
> + .u = {
> + .slave = &dw9710_slave,
> + },
> +};
> +
> +/**
> + * dw9710_probe - Probes the driver for valid I2C attachment.
> + * @client: Pointer to structure of I2C client.
> + *
> + * Returns 0 if successful, or -EBUSY if unable to get client attached data.
> + **/
> +static int
> +dw9710_probe(struct i2c_client *client, const struct i2c_device_id *id)
> +{
> + struct dw9710_device *lens = &dw9710;
> + int err;
> +
> + dev_info(&client->dev, "dw9710 probe called....\n");
> +
> + if (i2c_get_clientdata(client)) {
> + printk(KERN_ERR " DTA BUSY %s\n", client->name);
> + return -EBUSY;
> + }
> +
> + lens->pdata = client->dev.platform_data;
> +
> + if (!lens->pdata) {
> + dev_err(&client->dev, "no platform data?\n");
> + return -ENODEV;
> + }
> +
> + lens->v4l2_int_device = &dw9710_int_device;
> +
> + lens->i2c_client = client;
> + i2c_set_clientdata(client, lens);
> +
> + err = v4l2_int_device_register(lens->v4l2_int_device);
> + if (err) {
> + printk(KERN_ERR "Failed to Register "
> + DRIVER_NAME " as V4L2 device.\n");
> + i2c_set_clientdata(client, NULL);
> + } else {
> + printk(KERN_ERR "Registered "
> + DRIVER_NAME " as V4L2 device.\n");
> + }
> +
> + return 0;
> +}
> +
> +/**
> + * dw9710_remove - Routine when device its unregistered from I2C
> + * @client: Pointer to structure of I2C client.
> + *
> + * Returns 0 if successful, or -ENODEV if the client isn't attached.
> + **/
> +static int __exit dw9710_remove(struct i2c_client *client)
> +{
> + if (!client->adapter)
> + return -ENODEV;
> +
> + i2c_set_clientdata(client, NULL);
> + return 0;
> +}
> +
> +/**
> + * dw9710_init - Module initialisation.
> + *
> + * Returns 0 if successful, or -EINVAL if device couldn't be initialized, or
> + * added as a character device.
> + **/
> +static int __init dw9710_init(void)
> +{
> + int err = -EINVAL;
> +
> + err = i2c_add_driver(&dw9710_i2c_driver);
> + if (err)
> + goto fail;
> + return err;
> +fail:
> + printk(KERN_ERR "Failed to register " DRIVER_NAME ".\n");
> + return err;
> +}
> +late_initcall(dw9710_init);
> +
> +/**
> + * dw9710_cleanup - Module cleanup.
> + **/
> +static void __exit dw9710_cleanup(void)
> +{
> + i2c_del_driver(&dw9710_i2c_driver);
> +}
> +module_exit(dw9710_cleanup);
> +
> +MODULE_AUTHOR("Texas Instruments");
> +MODULE_LICENSE("GPL");
> +MODULE_DESCRIPTION("DW9710 LENS driver");
> diff --git a/drivers/media/video/dw9710.h b/drivers/media/video/dw9710.h
> new file mode 100644
> index 0000000..e4050a4
> --- /dev/null
> +++ b/drivers/media/video/dw9710.h
> @@ -0,0 +1,59 @@
> +/*
> + * drivers/media/video/dw9710.h
> + *
> + * Register defines for Auto Focus device
> + *
> + * Copyright (C) 2008 Texas Instruments.
> + *
> + * Contributors:
> + * Troy Laramy <[email protected]>
> + * Mohit Jalori <[email protected]>
> + *
> + * This file is licensed under the terms of the GNU General Public License
> + * version 2. This program is licensed "as is" without any warranty of any
> + * kind, whether express or implied.
> + *
> + */
> +
> +#ifndef CAMAF_DW9710_H
> +#define CAMAF_DW9710_H
> +
> +#define DW9710_AF_I2C_ADDR 0x0C
> +#define DW9710_NAME "DW9710"
> +#define DW9710_I2C_RETRY_COUNT 5
> +#define MAX_FOCUS_POS 0xFF
> +
> +#define CAMAF_DW9710_DISABLE 0x1
> +#define CAMAF_DW9710_ENABLE 0x0
> +#define CAMAF_DW9710_POWERDN(ARG) (((ARG) & 0x1) << 15)
> +#define CAMAF_DW9710_POWERDN_R(ARG) (((ARG) >> 15) & 0x1)
> +
> +#define CAMAF_DW9710_DATA(ARG) (((ARG) & 0xFF) << 6)
> +#define CAMAF_DW9710_DATA_R(ARG) (((ARG) >> 6) & 0xFF)
> +#define CAMAF_FREQUENCY_EQ1(mclk) ((u16)(mclk/16000))
> +
> +/* State of lens */
> +#define LENS_DETECTED 1
> +#define LENS_NOT_DETECTED 0
> +
> +/* Focus control values */
> +#define DEF_LENS_POSN 0 /* 0x7F */
> +#define LENS_POSN_STEP 1
> +
> +
> +/**
> + * struct dw9710_platform_data - platform data values and access functions
> + * @power_set: Power state access function, zero is off, non-zero is on.
> + * @priv_data_set: device private data (pointer) access function
> + */
> +struct dw9710_platform_data {
> + int (*power_set)(enum v4l2_power power);
> + int (*priv_data_set)(void *);
> +};
> +
> +/*
> + * Sets the specified focus value [0(far) - 100(near)]
> + */
> +int dw9710_af_setfocus(u16 posn);
> +int dw9710_af_getfocus(u16 *value);
> +#endif /* End of of CAMAF_DW9710_H */
This header seems to be a mix of kernel-public and driver-private things.
Please split this up. Anything kernel-public should go to
include/media/dw9710.h. Driver-private data should either be in the source
or in a header next to the source.
Regards,
Hans
> --
> 1.5.6.5
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--
Hans Verkuil - video4linux developer - sponsored by TANDBERG
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