| Message ID | 1352938546-22104-1-git-send-email-laurent.pinchart@ideasonboard.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
Hi Laurent, Thanks for the patch! On Thu, Nov 15, 2012 at 01:15:46AM +0100, Laurent Pinchart wrote: > The AD5820 is a voice coil motor controller typically used to control > lens position in digital cameras. > > Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > --- > drivers/media/i2c/Kconfig | 9 + > drivers/media/i2c/Makefile | 1 + > drivers/media/i2c/ad5820.c | 496 ++++++++++++++++++++++++++++++++++++++++++++ > include/media/ad5820.h | 30 +++ > 4 files changed, 536 insertions(+), 0 deletions(-) > create mode 100644 drivers/media/i2c/ad5820.c > create mode 100644 include/media/ad5820.h > > Hi Florian, > > This is the ad5820 driver I've told you about. The code is compile-tested only > as I haven't had time to try it on an N900 (the only device I own that > includes an ad5820). > > It should be quite easy to adapt the driver to support both the ad5820 and the > ad5821. Would you have time to give it a try ? > > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig > index 24d78e2..65597cf 100644 > --- a/drivers/media/i2c/Kconfig > +++ b/drivers/media/i2c/Kconfig > @@ -534,6 +534,15 @@ config VIDEO_AS3645A > This is a driver for the AS3645A and LM3555 flash controllers. It has > build in control for flash, torch and indicator LEDs. > > +comment "Lens controllers" > + > +config VIDEO_AD5820 > + tristate "AD5820 lens voice coil support" > + depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER > + ---help--- > + This is a driver for the AD5820 camera lens voice coil. > + It is used for example in Nokia RX51. > + > comment "Video improvement chips" > > config VIDEO_UPD64031A > diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile > index b1d62df..975cfb8 100644 > --- a/drivers/media/i2c/Makefile > +++ b/drivers/media/i2c/Makefile > @@ -58,6 +58,7 @@ obj-$(CONFIG_VIDEO_SR030PC30) += sr030pc30.o > obj-$(CONFIG_VIDEO_NOON010PC30) += noon010pc30.o > obj-$(CONFIG_VIDEO_S5K6AA) += s5k6aa.o > obj-$(CONFIG_VIDEO_S5K4ECGX) += s5k4ecgx.o > +obj-$(CONFIG_VIDEO_AD5820) += ad5820.o > obj-$(CONFIG_VIDEO_ADP1653) += adp1653.o > obj-$(CONFIG_VIDEO_AS3645A) += as3645a.o > obj-$(CONFIG_VIDEO_SMIAPP_PLL) += smiapp-pll.o > diff --git a/drivers/media/i2c/ad5820.c b/drivers/media/i2c/ad5820.c > new file mode 100644 > index 0000000..995774f > --- /dev/null > +++ b/drivers/media/i2c/ad5820.c > @@ -0,0 +1,496 @@ > +/* > + * AD5820 DAC driver for camera voice coil focus. > + * > + * Copyright (C) 2008 Nokia Corporation > + * Copyright (C) 2007 Texas Instruments Wow. This is old. > + * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > + * Sakari Ailus <sakari.ailus@iki.fi> > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms of the GNU General Public License > + * version 2 as published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, but > + * WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + * General Public License for more details. > + */ > + > +#include <linux/bitops.h> > +#include <linux/delay.h> > +#include <linux/errno.h> > +#include <linux/gpio.h> > +#include <linux/i2c.h> > +#include <linux/kernel.h> > +#include <linux/module.h> > +#include <linux/regulator/consumer.h> > +#include <linux/sched.h> > +#include <linux/slab.h> Do you need all of these? E.g. delay.h and sched.h are probably not needed. > + > +#include <media/ad5820.h> > +#include <media/v4l2-ctrls.h> > +#include <media/v4l2-device.h> > +#include <media/v4l2-subdev.h> > + > +/* Register definitions */ > +#define AD5820_POWER_DOWN (1 << 15) > +#define AD5820_DAC_SHIFT 4 > +#define AD5820_RAMP_MODE_LINEAR (0 << 3) > +#define AD5820_RAMP_MODE_64_16 (1 << 3) > + > +#define CODE_TO_RAMP_US(s) ((s) == 0 ? 0 : (1 << ((s) - 1)) * 50) > +#define RAMP_US_TO_CODE(c) fls(((c) + ((c)>>1)) / 50) > + > +struct ad5820_device { > + struct v4l2_subdev subdev; > + > + struct regulator *vana; > + int xshutdown; > + > + struct v4l2_ctrl_handler ctrls; > + u32 focus_absolute; > + u32 focus_ramp_time; > + u32 focus_ramp_mode; > + > + struct mutex power_lock; > + int power_count; > + > + int standby:1; > +}; > + > +#define to_ad5820_device(sd) container_of(sd, struct ad5820_device, subdev) > + > +/** > + * @brief I2C write using i2c_transfer(). > + * @param coil - the driver data structure > + * @param data - register value to be written > + * @returns nonnegative on success, negative if failed > + */ > +static int ad5820_write(struct ad5820_device *coil, u16 data) > +{ > + struct i2c_client *client = v4l2_get_subdevdata(&coil->subdev); > + struct i2c_msg msg; > + int r; > + > + if (!client->adapter) > + return -ENODEV; > + > + data = cpu_to_be16(data); > + msg.addr = client->addr; > + msg.flags = 0; > + msg.len = 2; > + msg.buf = (u8 *)&data; > + > + r = i2c_transfer(client->adapter, &msg, 1); I know we've gotten used to i2c_transfer(), but wouldn't i2c_master_{send,recv}() be better for the task? > + if (r < 0) { > + dev_err(&client->dev, "write failed, error %d\n", r); > + return r; > + } > + > + return 0; > +} > + > +/** > + * @brief I2C read using i2c_transfer(). > + * @param coil - the driver data structure > + * @returns unsigned 16-bit register value on success, negative if failed > + */ > +static int ad5820_read(struct ad5820_device *coil) > +{ > + struct i2c_client *client = v4l2_get_subdevdata(&coil->subdev); > + struct i2c_msg msg; > + int r; > + u16 data = 0; > + > + if (!client->adapter) > + return -ENODEV; > + > + msg.addr = client->addr; > + msg.flags = I2C_M_RD; > + msg.len = 2; > + msg.buf = (u8 *)&data; > + > + r = i2c_transfer(client->adapter, &msg, 1); > + if (r < 0) { > + dev_err(&client->dev, "read failed, error %d\n", r); > + return r; > + } > + > + return be16_to_cpu(data); > +} > + > +/* Calculate status word and write it to the device based on current > + * values of V4L2 controls. It is assumed that the stored V4L2 control > + * values are properly limited and rounded. */ > +static int ad5820_update_hw(struct ad5820_device *coil) > +{ > + u16 status; > + > + status = RAMP_US_TO_CODE(coil->focus_ramp_time); > + status |= coil->focus_ramp_mode > + ? AD5820_RAMP_MODE_64_16 : AD5820_RAMP_MODE_LINEAR; > + status |= coil->focus_absolute << AD5820_DAC_SHIFT; > + > + if (coil->standby) > + status |= AD5820_POWER_DOWN; > + > + return ad5820_write(coil, status); > +} > + > +/* -------------------------------------------------------------------------- > + * Power handling > + */ > + > +static void ad5820_power_off(struct ad5820_device *coil) > +{ > + if (coil->xshutdown != -1) > + gpio_set_value(coil->xshutdown, 0); > + > + regulator_disable(coil->vana); > +} > + > +static int ad5820_power_on(struct ad5820_device *coil) > +{ > + int ret; > + > + ret = regulator_enable(coil->vana); > + if (ret < 0) > + return ret; > + > + if (coil->xshutdown != -1) > + gpio_set_value(coil->xshutdown, 1); > + > + return 0; > +} > + > +/* -------------------------------------------------------------------------- > + * V4L2 controls > + */ > + > +#define V4L2_CID_FOCUS_AD5820_RAMP_TIME (V4L2_CID_USER_BASE | 0x1000) > +#define V4L2_CID_FOCUS_AD5820_RAMP_MODE (V4L2_CID_USER_BASE | 0x1001) > + > +static int ad5820_set_ctrl(struct v4l2_ctrl *ctrl) > +{ > + struct ad5820_device *coil = > + container_of(ctrl->handler, struct ad5820_device, ctrls); > + u32 code; > + int r = 0; > + > + switch (ctrl->id) { > + case V4L2_CID_FOCUS_ABSOLUTE: > + coil->focus_absolute = ctrl->val; > + return ad5820_update_hw(coil); > + > + case V4L2_CID_FOCUS_AD5820_RAMP_TIME: > + code = RAMP_US_TO_CODE(ctrl->val); > + ctrl->val = CODE_TO_RAMP_US(code); > + coil->focus_ramp_time = ctrl->val; > + break; > + > + case V4L2_CID_FOCUS_AD5820_RAMP_MODE: > + coil->focus_ramp_mode = ctrl->val; > + break; > + } > + > + return r; > +} > + > +static const struct v4l2_ctrl_ops ad5820_ctrl_ops = { > + .s_ctrl = ad5820_set_ctrl, > +}; > + > +static const char * const ad5820_focus_menu[] = { > + "Linear ramp", > + "64/16 ramp", > +}; > + > +static const struct v4l2_ctrl_config ad5820_ctrls[] = { > + { > + .ops = &ad5820_ctrl_ops, > + .id = V4L2_CID_FOCUS_AD5820_RAMP_TIME, > + .type = V4L2_CTRL_TYPE_INTEGER, > + .name = "Focus ramping time [us]", > + .min = 0, > + .max = 3200, > + .step = 50, > + .def = 0, > + .flags = 0, > + }, > + { > + .ops = &ad5820_ctrl_ops, > + .id = V4L2_CID_FOCUS_AD5820_RAMP_MODE, > + .type = V4L2_CTRL_TYPE_MENU, > + .name = "Focus ramping mode", > + .min = 0, > + .max = ARRAY_SIZE(ad5820_focus_menu), > + .step = 0, > + .def = 0, > + .flags = 0, > + .qmenu = ad5820_focus_menu, > + }, > +}; > + > +/* -------------------------------------------------------------------------- > + * V4L2 subdev operations > + */ > + > +static int __ad5820_set_power(struct ad5820_device *coil, bool on) > +{ > + int ret; > + > + if (!on) { > + /* Go to standby first as real power off my be denied by the > + * hardware (single power line control for both coil and > + * sensor). > + */ > + coil->standby = 1; > + ad5820_update_hw(coil); > + ad5820_power_off(coil); > + return 0; > + } > + > + ret = ad5820_power_on(coil); > + if (ret < 0) > + return ret; > + > + /* Restore the hardware settings. */ > + coil->standby = 0; > + ret = ad5820_update_hw(coil); > + if (ret < 0) { > + coil->standby = 1; > + return ret; > + } > + > + return 0; > +} > + > +static int ad5820_set_power(struct v4l2_subdev *subdev, int on) > +{ > + struct ad5820_device *coil = to_ad5820_device(subdev); > + int ret = 0; > + > + mutex_lock(&coil->power_lock); > + > + /* If the power count is modified from 0 to != 0 or from != 0 to 0, > + * update the power state. > + */ > + if (coil->power_count == !on) { > + ret = __ad5820_set_power(coil, !!on); > + if (ret < 0) > + goto done; > + } > + > + /* Update the power count. */ > + coil->power_count += on ? 1 : -1; > + WARN_ON(coil->power_count < 0); > + > +done: > + mutex_unlock(&coil->power_lock); > + return ret; > +} > + > +static int ad5820_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) > +{ > + return ad5820_set_power(sd, 1); > +} > + > +static int ad5820_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) > +{ > + return ad5820_set_power(sd, 0); > +} > + > +static const struct v4l2_subdev_core_ops ad5820_core_ops = { > + .s_power = ad5820_set_power, > +}; > + > +static const struct v4l2_subdev_ops ad5820_ops = { > + .core = &ad5820_core_ops, > +}; > + > +static const struct v4l2_subdev_internal_ops ad5820_internal_ops = { > + .open = ad5820_open, > + .close = ad5820_close, > +}; > + > +/* -------------------------------------------------------------------------- > + * I2C driver > + */ > +#ifdef CONFIG_PM > + > +static int ad5820_suspend(struct device *dev) > +{ > + struct i2c_client *client = to_i2c_client(dev); > + struct v4l2_subdev *subdev = i2c_get_clientdata(client); > + struct ad5820_device *coil = to_ad5820_device(subdev); > + > + if (!coil->power_count) > + return 0; > + > + ad5820_power_off(coil); > + return 0; > +} > + > +static int ad5820_resume(struct device *dev) > +{ > + struct i2c_client *client = to_i2c_client(dev); > + struct v4l2_subdev *subdev = i2c_get_clientdata(client); > + struct ad5820_device *coil = to_ad5820_device(subdev); > + > + if (!coil->power_count) > + return 0; > + > + return __ad5820_set_power(coil, true); > +} > + > +#endif /* CONFIG_PM */ > + > +static int ad5820_detect(struct ad5820_device *coil) > +{ > + const u16 status = AD5820_POWER_DOWN | 0x3ff0; > + int ret; > + > + if (ad5820_power_on(coil) < 0) > + return -ENODEV; > + > + if (ad5820_write(coil, status) || ad5820_read(coil) != status) { > + ad5820_power_off(coil); > + return -ENODEV; > + } > + > + __ad5820_set_power(coil, false); > + return ret; > +} > + > +static int ad5820_probe(struct i2c_client *client, > + const struct i2c_device_id *devid) > +{ > + struct ad5820_platform_data *pdata = client->dev.platform_data; > + struct ad5820_device *coil; > + unsigned int i; > + int ret = -ENODEV; > + > + coil = kzalloc(sizeof(*coil), GFP_KERNEL); > + if (coil == NULL) > + return -ENOMEM; > + > + mutex_init(&coil->power_lock); > + coil->focus_absolute = 0; > + coil->focus_ramp_time = 0; > + coil->focus_ramp_mode = 0; > + coil->xshutdown = -1; > + > + coil->vana = regulator_get(&client->dev, "VANA"); > + if (IS_ERR(coil->vana)) { > + dev_err(&client->dev, "could not get regulator for vana\n"); > + goto done; > + } > + > + if (pdata && pdata->xshutdown != -1) { > + ret = gpio_request_one(pdata->xshutdown, GPIOF_OUT_INIT_LOW, > + "ad5820_xshutdown"); > + if (ret < 0) > + goto done; > + > + coil->xshutdown = pdata->xshutdown; > + } > + > + ret = ad5820_detect(coil); > + if (ret < 0) { > + dev_err(&client->dev, "not detected\n"); > + goto done; > + } > + > + v4l2_ctrl_handler_init(&coil->ctrls, ARRAY_SIZE(ad5820_ctrls) + 1); > + > + /* V4L2_CID_FOCUS_ABSOLUTE > + * > + * Minimum current is 0 mA, maximum is 100 mA. Thus, 1 code is > + * equivalent to 100/1023 = 0.0978 mA. Nevertheless, we do not use [mA] > + * for focus position, because it is meaningless for user. Meaningful > + * would be to use focus distance or even its inverse, but since the > + * driver doesn't have sufficiently knowledge to do the conversion, we > + * will just use abstract codes here. In any case, smaller value = focus > + * position farther from camera. The default zero value means focus at > + * infinity, and also least current consumption. > + */ > + v4l2_ctrl_new_std(&coil->ctrls, &ad5820_ctrl_ops, > + V4L2_CID_FOCUS_ABSOLUTE, 0, 1023, 1, 0); > + > + /* V4L2_CID_TEST_PATTERN and V4L2_CID_MODE_* */ > + for (i = 0; i < ARRAY_SIZE(ad5820_ctrls); ++i) > + v4l2_ctrl_new_custom(&coil->ctrls, &ad5820_ctrls[i], NULL); > + > + if (coil->ctrls.error) { > + ret = coil->ctrls.error; > + goto done; > + } > + > + coil->subdev.ctrl_handler = &coil->ctrls; > + > + v4l2_i2c_subdev_init(&coil->subdev, client, &ad5820_ops); > + coil->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE; > + coil->subdev.internal_ops = &ad5820_internal_ops; > + > + ret = media_entity_init(&coil->subdev.entity, 0, NULL, 0); > + if (ret < 0) > + goto done; > + > + ret = 0; > + > +done: > + if (ret < 0) { > + v4l2_ctrl_handler_free(&coil->ctrls); > + media_entity_cleanup(&coil->subdev.entity); > + > + if (coil->xshutdown != -1) > + gpio_free(coil->xshutdown); > + regulator_put(coil->vana); > + > + kfree(coil); > + } > + > + return ret; > +} > + > +static int __exit ad5820_remove(struct i2c_client *client) > +{ > + struct v4l2_subdev *subdev = i2c_get_clientdata(client); > + struct ad5820_device *coil = to_ad5820_device(subdev); > + > + v4l2_device_unregister_subdev(&coil->subdev); > + v4l2_ctrl_handler_free(&coil->ctrls); > + media_entity_cleanup(&coil->subdev.entity); > + > + if (coil->xshutdown != -1) > + gpio_free(coil->xshutdown); > + regulator_put(coil->vana); > + > + kfree(coil); > + return 0; > +} > + > +static const struct i2c_device_id ad5820_id_table[] = { > + { AD5820_NAME, 0 }, > + { } > +}; > +MODULE_DEVICE_TABLE(i2c, ad5820_id_table); > + > +static SIMPLE_DEV_PM_OPS(ad5820_pm_ops, ad5820_suspend, ad5820_resume); > + > +static struct i2c_driver ad5820_i2c_driver = { > + .driver = { > + .name = AD5820_NAME, > + .pm = &ad5820_pm_ops, > + }, > + .probe = ad5820_probe, > + .remove = __exit_p(ad5820_remove), > + .id_table = ad5820_id_table, > +}; > + > +module_i2c_driver(ad5820_i2c_driver); > + > +MODULE_AUTHOR("Tuukka Toivonen <tuukka.o.toivonen@nokia.com>"); I think Tuukka's e-mail is wrong here. tuukkat76@gmail.com? Cc Tuukka. > +MODULE_DESCRIPTION("AD5820 camera lens driver"); > +MODULE_LICENSE("GPL"); > diff --git a/include/media/ad5820.h b/include/media/ad5820.h > new file mode 100644 > index 0000000..2c28131 > --- /dev/null > +++ b/include/media/ad5820.h > @@ -0,0 +1,30 @@ > +/* > + * AD5820 DAC driver for camera voice coil focus. > + * > + * Copyright (C) 2008 Nokia Corporation > + * Copyright (C) 2007 Texas Instruments > + * > + * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com> > + * Sakari Ailus <sakari.ailus@iki.fi> > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms of the GNU General Public License > + * version 2 as published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, but > + * WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + * General Public License for more details. > + */ > + > +#ifndef __AD5820_H__ > +#define __AD5820_H__ > + > +#define AD5820_NAME "ad5820" > +#define AD5820_I2C_ADDR (0x18 >> 1) > + > +struct ad5820_platform_data { > + int xshutdown; > +}; > + > +#endif /* __AD5820_H__ */ The patch itself looks fine, but I think the bigger question is: what's the interface for such low-level lens control chips? Based on what I've seen in the past, the vast majority of these are very simple but a yet diverse set of devices in terms of how they are controlled. So until we've got more of them the private controls are probably best we can do.
diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig index 24d78e2..65597cf 100644 --- a/drivers/media/i2c/Kconfig +++ b/drivers/media/i2c/Kconfig @@ -534,6 +534,15 @@ config VIDEO_AS3645A This is a driver for the AS3645A and LM3555 flash controllers. It has build in control for flash, torch and indicator LEDs. +comment "Lens controllers" + +config VIDEO_AD5820 + tristate "AD5820 lens voice coil support" + depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER + ---help--- + This is a driver for the AD5820 camera lens voice coil. + It is used for example in Nokia RX51. + comment "Video improvement chips" config VIDEO_UPD64031A diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile index b1d62df..975cfb8 100644 --- a/drivers/media/i2c/Makefile +++ b/drivers/media/i2c/Makefile @@ -58,6 +58,7 @@ obj-$(CONFIG_VIDEO_SR030PC30) += sr030pc30.o obj-$(CONFIG_VIDEO_NOON010PC30) += noon010pc30.o obj-$(CONFIG_VIDEO_S5K6AA) += s5k6aa.o obj-$(CONFIG_VIDEO_S5K4ECGX) += s5k4ecgx.o +obj-$(CONFIG_VIDEO_AD5820) += ad5820.o obj-$(CONFIG_VIDEO_ADP1653) += adp1653.o obj-$(CONFIG_VIDEO_AS3645A) += as3645a.o obj-$(CONFIG_VIDEO_SMIAPP_PLL) += smiapp-pll.o diff --git a/drivers/media/i2c/ad5820.c b/drivers/media/i2c/ad5820.c new file mode 100644 index 0000000..995774f --- /dev/null +++ b/drivers/media/i2c/ad5820.c @@ -0,0 +1,496 @@ +/* + * AD5820 DAC driver for camera voice coil focus. + * + * Copyright (C) 2008 Nokia Corporation + * Copyright (C) 2007 Texas Instruments + * + * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com> + * Sakari Ailus <sakari.ailus@iki.fi> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ + +#include <linux/bitops.h> +#include <linux/delay.h> +#include <linux/errno.h> +#include <linux/gpio.h> +#include <linux/i2c.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/regulator/consumer.h> +#include <linux/sched.h> +#include <linux/slab.h> + +#include <media/ad5820.h> +#include <media/v4l2-ctrls.h> +#include <media/v4l2-device.h> +#include <media/v4l2-subdev.h> + +/* Register definitions */ +#define AD5820_POWER_DOWN (1 << 15) +#define AD5820_DAC_SHIFT 4 +#define AD5820_RAMP_MODE_LINEAR (0 << 3) +#define AD5820_RAMP_MODE_64_16 (1 << 3) + +#define CODE_TO_RAMP_US(s) ((s) == 0 ? 0 : (1 << ((s) - 1)) * 50) +#define RAMP_US_TO_CODE(c) fls(((c) + ((c)>>1)) / 50) + +struct ad5820_device { + struct v4l2_subdev subdev; + + struct regulator *vana; + int xshutdown; + + struct v4l2_ctrl_handler ctrls; + u32 focus_absolute; + u32 focus_ramp_time; + u32 focus_ramp_mode; + + struct mutex power_lock; + int power_count; + + int standby:1; +}; + +#define to_ad5820_device(sd) container_of(sd, struct ad5820_device, subdev) + +/** + * @brief I2C write using i2c_transfer(). + * @param coil - the driver data structure + * @param data - register value to be written + * @returns nonnegative on success, negative if failed + */ +static int ad5820_write(struct ad5820_device *coil, u16 data) +{ + struct i2c_client *client = v4l2_get_subdevdata(&coil->subdev); + struct i2c_msg msg; + int r; + + if (!client->adapter) + return -ENODEV; + + data = cpu_to_be16(data); + msg.addr = client->addr; + msg.flags = 0; + msg.len = 2; + msg.buf = (u8 *)&data; + + r = i2c_transfer(client->adapter, &msg, 1); + if (r < 0) { + dev_err(&client->dev, "write failed, error %d\n", r); + return r; + } + + return 0; +} + +/** + * @brief I2C read using i2c_transfer(). + * @param coil - the driver data structure + * @returns unsigned 16-bit register value on success, negative if failed + */ +static int ad5820_read(struct ad5820_device *coil) +{ + struct i2c_client *client = v4l2_get_subdevdata(&coil->subdev); + struct i2c_msg msg; + int r; + u16 data = 0; + + if (!client->adapter) + return -ENODEV; + + msg.addr = client->addr; + msg.flags = I2C_M_RD; + msg.len = 2; + msg.buf = (u8 *)&data; + + r = i2c_transfer(client->adapter, &msg, 1); + if (r < 0) { + dev_err(&client->dev, "read failed, error %d\n", r); + return r; + } + + return be16_to_cpu(data); +} + +/* Calculate status word and write it to the device based on current + * values of V4L2 controls. It is assumed that the stored V4L2 control + * values are properly limited and rounded. */ +static int ad5820_update_hw(struct ad5820_device *coil) +{ + u16 status; + + status = RAMP_US_TO_CODE(coil->focus_ramp_time); + status |= coil->focus_ramp_mode + ? AD5820_RAMP_MODE_64_16 : AD5820_RAMP_MODE_LINEAR; + status |= coil->focus_absolute << AD5820_DAC_SHIFT; + + if (coil->standby) + status |= AD5820_POWER_DOWN; + + return ad5820_write(coil, status); +} + +/* -------------------------------------------------------------------------- + * Power handling + */ + +static void ad5820_power_off(struct ad5820_device *coil) +{ + if (coil->xshutdown != -1) + gpio_set_value(coil->xshutdown, 0); + + regulator_disable(coil->vana); +} + +static int ad5820_power_on(struct ad5820_device *coil) +{ + int ret; + + ret = regulator_enable(coil->vana); + if (ret < 0) + return ret; + + if (coil->xshutdown != -1) + gpio_set_value(coil->xshutdown, 1); + + return 0; +} + +/* -------------------------------------------------------------------------- + * V4L2 controls + */ + +#define V4L2_CID_FOCUS_AD5820_RAMP_TIME (V4L2_CID_USER_BASE | 0x1000) +#define V4L2_CID_FOCUS_AD5820_RAMP_MODE (V4L2_CID_USER_BASE | 0x1001) + +static int ad5820_set_ctrl(struct v4l2_ctrl *ctrl) +{ + struct ad5820_device *coil = + container_of(ctrl->handler, struct ad5820_device, ctrls); + u32 code; + int r = 0; + + switch (ctrl->id) { + case V4L2_CID_FOCUS_ABSOLUTE: + coil->focus_absolute = ctrl->val; + return ad5820_update_hw(coil); + + case V4L2_CID_FOCUS_AD5820_RAMP_TIME: + code = RAMP_US_TO_CODE(ctrl->val); + ctrl->val = CODE_TO_RAMP_US(code); + coil->focus_ramp_time = ctrl->val; + break; + + case V4L2_CID_FOCUS_AD5820_RAMP_MODE: + coil->focus_ramp_mode = ctrl->val; + break; + } + + return r; +} + +static const struct v4l2_ctrl_ops ad5820_ctrl_ops = { + .s_ctrl = ad5820_set_ctrl, +}; + +static const char * const ad5820_focus_menu[] = { + "Linear ramp", + "64/16 ramp", +}; + +static const struct v4l2_ctrl_config ad5820_ctrls[] = { + { + .ops = &ad5820_ctrl_ops, + .id = V4L2_CID_FOCUS_AD5820_RAMP_TIME, + .type = V4L2_CTRL_TYPE_INTEGER, + .name = "Focus ramping time [us]", + .min = 0, + .max = 3200, + .step = 50, + .def = 0, + .flags = 0, + }, + { + .ops = &ad5820_ctrl_ops, + .id = V4L2_CID_FOCUS_AD5820_RAMP_MODE, + .type = V4L2_CTRL_TYPE_MENU, + .name = "Focus ramping mode", + .min = 0, + .max = ARRAY_SIZE(ad5820_focus_menu), + .step = 0, + .def = 0, + .flags = 0, + .qmenu = ad5820_focus_menu, + }, +}; + +/* -------------------------------------------------------------------------- + * V4L2 subdev operations + */ + +static int __ad5820_set_power(struct ad5820_device *coil, bool on) +{ + int ret; + + if (!on) { + /* Go to standby first as real power off my be denied by the + * hardware (single power line control for both coil and + * sensor). + */ + coil->standby = 1; + ad5820_update_hw(coil); + ad5820_power_off(coil); + return 0; + } + + ret = ad5820_power_on(coil); + if (ret < 0) + return ret; + + /* Restore the hardware settings. */ + coil->standby = 0; + ret = ad5820_update_hw(coil); + if (ret < 0) { + coil->standby = 1; + return ret; + } + + return 0; +} + +static int ad5820_set_power(struct v4l2_subdev *subdev, int on) +{ + struct ad5820_device *coil = to_ad5820_device(subdev); + int ret = 0; + + mutex_lock(&coil->power_lock); + + /* If the power count is modified from 0 to != 0 or from != 0 to 0, + * update the power state. + */ + if (coil->power_count == !on) { + ret = __ad5820_set_power(coil, !!on); + if (ret < 0) + goto done; + } + + /* Update the power count. */ + coil->power_count += on ? 1 : -1; + WARN_ON(coil->power_count < 0); + +done: + mutex_unlock(&coil->power_lock); + return ret; +} + +static int ad5820_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) +{ + return ad5820_set_power(sd, 1); +} + +static int ad5820_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) +{ + return ad5820_set_power(sd, 0); +} + +static const struct v4l2_subdev_core_ops ad5820_core_ops = { + .s_power = ad5820_set_power, +}; + +static const struct v4l2_subdev_ops ad5820_ops = { + .core = &ad5820_core_ops, +}; + +static const struct v4l2_subdev_internal_ops ad5820_internal_ops = { + .open = ad5820_open, + .close = ad5820_close, +}; + +/* -------------------------------------------------------------------------- + * I2C driver + */ +#ifdef CONFIG_PM + +static int ad5820_suspend(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct v4l2_subdev *subdev = i2c_get_clientdata(client); + struct ad5820_device *coil = to_ad5820_device(subdev); + + if (!coil->power_count) + return 0; + + ad5820_power_off(coil); + return 0; +} + +static int ad5820_resume(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct v4l2_subdev *subdev = i2c_get_clientdata(client); + struct ad5820_device *coil = to_ad5820_device(subdev); + + if (!coil->power_count) + return 0; + + return __ad5820_set_power(coil, true); +} + +#endif /* CONFIG_PM */ + +static int ad5820_detect(struct ad5820_device *coil) +{ + const u16 status = AD5820_POWER_DOWN | 0x3ff0; + int ret; + + if (ad5820_power_on(coil) < 0) + return -ENODEV; + + if (ad5820_write(coil, status) || ad5820_read(coil) != status) { + ad5820_power_off(coil); + return -ENODEV; + } + + __ad5820_set_power(coil, false); + return ret; +} + +static int ad5820_probe(struct i2c_client *client, + const struct i2c_device_id *devid) +{ + struct ad5820_platform_data *pdata = client->dev.platform_data; + struct ad5820_device *coil; + unsigned int i; + int ret = -ENODEV; + + coil = kzalloc(sizeof(*coil), GFP_KERNEL); + if (coil == NULL) + return -ENOMEM; + + mutex_init(&coil->power_lock); + coil->focus_absolute = 0; + coil->focus_ramp_time = 0; + coil->focus_ramp_mode = 0; + coil->xshutdown = -1; + + coil->vana = regulator_get(&client->dev, "VANA"); + if (IS_ERR(coil->vana)) { + dev_err(&client->dev, "could not get regulator for vana\n"); + goto done; + } + + if (pdata && pdata->xshutdown != -1) { + ret = gpio_request_one(pdata->xshutdown, GPIOF_OUT_INIT_LOW, + "ad5820_xshutdown"); + if (ret < 0) + goto done; + + coil->xshutdown = pdata->xshutdown; + } + + ret = ad5820_detect(coil); + if (ret < 0) { + dev_err(&client->dev, "not detected\n"); + goto done; + } + + v4l2_ctrl_handler_init(&coil->ctrls, ARRAY_SIZE(ad5820_ctrls) + 1); + + /* V4L2_CID_FOCUS_ABSOLUTE + * + * Minimum current is 0 mA, maximum is 100 mA. Thus, 1 code is + * equivalent to 100/1023 = 0.0978 mA. Nevertheless, we do not use [mA] + * for focus position, because it is meaningless for user. Meaningful + * would be to use focus distance or even its inverse, but since the + * driver doesn't have sufficiently knowledge to do the conversion, we + * will just use abstract codes here. In any case, smaller value = focus + * position farther from camera. The default zero value means focus at + * infinity, and also least current consumption. + */ + v4l2_ctrl_new_std(&coil->ctrls, &ad5820_ctrl_ops, + V4L2_CID_FOCUS_ABSOLUTE, 0, 1023, 1, 0); + + /* V4L2_CID_TEST_PATTERN and V4L2_CID_MODE_* */ + for (i = 0; i < ARRAY_SIZE(ad5820_ctrls); ++i) + v4l2_ctrl_new_custom(&coil->ctrls, &ad5820_ctrls[i], NULL); + + if (coil->ctrls.error) { + ret = coil->ctrls.error; + goto done; + } + + coil->subdev.ctrl_handler = &coil->ctrls; + + v4l2_i2c_subdev_init(&coil->subdev, client, &ad5820_ops); + coil->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE; + coil->subdev.internal_ops = &ad5820_internal_ops; + + ret = media_entity_init(&coil->subdev.entity, 0, NULL, 0); + if (ret < 0) + goto done; + + ret = 0; + +done: + if (ret < 0) { + v4l2_ctrl_handler_free(&coil->ctrls); + media_entity_cleanup(&coil->subdev.entity); + + if (coil->xshutdown != -1) + gpio_free(coil->xshutdown); + regulator_put(coil->vana); + + kfree(coil); + } + + return ret; +} + +static int __exit ad5820_remove(struct i2c_client *client) +{ + struct v4l2_subdev *subdev = i2c_get_clientdata(client); + struct ad5820_device *coil = to_ad5820_device(subdev); + + v4l2_device_unregister_subdev(&coil->subdev); + v4l2_ctrl_handler_free(&coil->ctrls); + media_entity_cleanup(&coil->subdev.entity); + + if (coil->xshutdown != -1) + gpio_free(coil->xshutdown); + regulator_put(coil->vana); + + kfree(coil); + return 0; +} + +static const struct i2c_device_id ad5820_id_table[] = { + { AD5820_NAME, 0 }, + { } +}; +MODULE_DEVICE_TABLE(i2c, ad5820_id_table); + +static SIMPLE_DEV_PM_OPS(ad5820_pm_ops, ad5820_suspend, ad5820_resume); + +static struct i2c_driver ad5820_i2c_driver = { + .driver = { + .name = AD5820_NAME, + .pm = &ad5820_pm_ops, + }, + .probe = ad5820_probe, + .remove = __exit_p(ad5820_remove), + .id_table = ad5820_id_table, +}; + +module_i2c_driver(ad5820_i2c_driver); + +MODULE_AUTHOR("Tuukka Toivonen <tuukka.o.toivonen@nokia.com>"); +MODULE_DESCRIPTION("AD5820 camera lens driver"); +MODULE_LICENSE("GPL"); diff --git a/include/media/ad5820.h b/include/media/ad5820.h new file mode 100644 index 0000000..2c28131 --- /dev/null +++ b/include/media/ad5820.h @@ -0,0 +1,30 @@ +/* + * AD5820 DAC driver for camera voice coil focus. + * + * Copyright (C) 2008 Nokia Corporation + * Copyright (C) 2007 Texas Instruments + * + * Contact: Laurent Pinchart <laurent.pinchart@ideasonboard.com> + * Sakari Ailus <sakari.ailus@iki.fi> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * version 2 as published by the Free Software Foundation. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License for more details. + */ + +#ifndef __AD5820_H__ +#define __AD5820_H__ + +#define AD5820_NAME "ad5820" +#define AD5820_I2C_ADDR (0x18 >> 1) + +struct ad5820_platform_data { + int xshutdown; +}; + +#endif /* __AD5820_H__ */
The AD5820 is a voice coil motor controller typically used to control lens position in digital cameras. Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com> --- drivers/media/i2c/Kconfig | 9 + drivers/media/i2c/Makefile | 1 + drivers/media/i2c/ad5820.c | 496 ++++++++++++++++++++++++++++++++++++++++++++ include/media/ad5820.h | 30 +++ 4 files changed, 536 insertions(+), 0 deletions(-) create mode 100644 drivers/media/i2c/ad5820.c create mode 100644 include/media/ad5820.h Hi Florian, This is the ad5820 driver I've told you about. The code is compile-tested only as I haven't had time to try it on an N900 (the only device I own that includes an ad5820). It should be quite easy to adapt the driver to support both the ad5820 and the ad5821. Would you have time to give it a try ?