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1// SPDX-License-Identifier: GPL-2.0-only2/*3 * drivers/media/i2c/ad5820.c4 *5 * AD5820 DAC driver for camera voice coil focus.6 *7 * Copyright (C) 2008 Nokia Corporation8 * Copyright (C) 2007 Texas Instruments9 * Copyright (C) 2016 Pavel Machek <pavel@ucw.cz>10 *11 * Contact: Tuukka Toivonen <tuukkat76@gmail.com>12 * Sakari Ailus <sakari.ailus@iki.fi>13 *14 * Based on af_d88.c by Texas Instruments.15 */16 17#include <linux/errno.h>18#include <linux/i2c.h>19#include <linux/kernel.h>20#include <linux/module.h>21#include <linux/regulator/consumer.h>22#include <linux/gpio/consumer.h>23 24#include <media/v4l2-ctrls.h>25#include <media/v4l2-device.h>26#include <media/v4l2-subdev.h>27 28/* Register definitions */29#define AD5820_POWER_DOWN (1 << 15)30#define AD5820_DAC_SHIFT 431#define AD5820_RAMP_MODE_LINEAR (0 << 3)32#define AD5820_RAMP_MODE_64_16 (1 << 3)33 34#define CODE_TO_RAMP_US(s) ((s) == 0 ? 0 : (1 << ((s) - 1)) * 50)35#define RAMP_US_TO_CODE(c) fls(((c) + ((c)>>1)) / 50)36 37#define to_ad5820_device(sd) container_of(sd, struct ad5820_device, subdev)38 39struct ad5820_device {40 struct v4l2_subdev subdev;41 struct ad5820_platform_data *platform_data;42 struct regulator *vana;43 44 struct v4l2_ctrl_handler ctrls;45 u32 focus_absolute;46 u32 focus_ramp_time;47 u32 focus_ramp_mode;48 49 struct gpio_desc *enable_gpio;50 51 struct mutex power_lock;52 int power_count;53 54 bool standby;55};56 57static int ad5820_write(struct ad5820_device *coil, u16 data)58{59 struct i2c_client *client = v4l2_get_subdevdata(&coil->subdev);60 struct i2c_msg msg;61 __be16 be_data;62 int r;63 64 if (!client->adapter)65 return -ENODEV;66 67 be_data = cpu_to_be16(data);68 msg.addr = client->addr;69 msg.flags = 0;70 msg.len = 2;71 msg.buf = (u8 *)&be_data;72 73 r = i2c_transfer(client->adapter, &msg, 1);74 if (r < 0) {75 dev_err(&client->dev, "write failed, error %d\n", r);76 return r;77 }78 79 return 0;80}81 82/*83 * Calculate status word and write it to the device based on current84 * values of V4L2 controls. It is assumed that the stored V4L2 control85 * values are properly limited and rounded.86 */87static int ad5820_update_hw(struct ad5820_device *coil)88{89 u16 status;90 91 status = RAMP_US_TO_CODE(coil->focus_ramp_time);92 status |= coil->focus_ramp_mode93 ? AD5820_RAMP_MODE_64_16 : AD5820_RAMP_MODE_LINEAR;94 status |= coil->focus_absolute << AD5820_DAC_SHIFT;95 96 if (coil->standby)97 status |= AD5820_POWER_DOWN;98 99 return ad5820_write(coil, status);100}101 102/*103 * Power handling104 */105static int ad5820_power_off(struct ad5820_device *coil, bool standby)106{107 int ret = 0, ret2;108 109 /*110 * Go to standby first as real power off my be denied by the hardware111 * (single power line control for both coil and sensor).112 */113 if (standby) {114 coil->standby = true;115 ret = ad5820_update_hw(coil);116 }117 118 gpiod_set_value_cansleep(coil->enable_gpio, 0);119 120 ret2 = regulator_disable(coil->vana);121 if (ret)122 return ret;123 return ret2;124}125 126static int ad5820_power_on(struct ad5820_device *coil, bool restore)127{128 int ret;129 130 ret = regulator_enable(coil->vana);131 if (ret < 0)132 return ret;133 134 gpiod_set_value_cansleep(coil->enable_gpio, 1);135 136 if (restore) {137 /* Restore the hardware settings. */138 coil->standby = false;139 ret = ad5820_update_hw(coil);140 if (ret)141 goto fail;142 }143 return 0;144 145fail:146 gpiod_set_value_cansleep(coil->enable_gpio, 0);147 coil->standby = true;148 regulator_disable(coil->vana);149 150 return ret;151}152 153/*154 * V4L2 controls155 */156static int ad5820_set_ctrl(struct v4l2_ctrl *ctrl)157{158 struct ad5820_device *coil =159 container_of(ctrl->handler, struct ad5820_device, ctrls);160 161 switch (ctrl->id) {162 case V4L2_CID_FOCUS_ABSOLUTE:163 coil->focus_absolute = ctrl->val;164 return ad5820_update_hw(coil);165 }166 167 return 0;168}169 170static const struct v4l2_ctrl_ops ad5820_ctrl_ops = {171 .s_ctrl = ad5820_set_ctrl,172};173 174 175static int ad5820_init_controls(struct ad5820_device *coil)176{177 v4l2_ctrl_handler_init(&coil->ctrls, 1);178 179 /*180 * V4L2_CID_FOCUS_ABSOLUTE181 *182 * Minimum current is 0 mA, maximum is 100 mA. Thus, 1 code is183 * equivalent to 100/1023 = 0.0978 mA. Nevertheless, we do not use [mA]184 * for focus position, because it is meaningless for user. Meaningful185 * would be to use focus distance or even its inverse, but since the186 * driver doesn't have sufficiently knowledge to do the conversion, we187 * will just use abstract codes here. In any case, smaller value = focus188 * position farther from camera. The default zero value means focus at189 * infinity, and also least current consumption.190 */191 v4l2_ctrl_new_std(&coil->ctrls, &ad5820_ctrl_ops,192 V4L2_CID_FOCUS_ABSOLUTE, 0, 1023, 1, 0);193 194 if (coil->ctrls.error)195 return coil->ctrls.error;196 197 coil->focus_absolute = 0;198 coil->focus_ramp_time = 0;199 coil->focus_ramp_mode = 0;200 201 coil->subdev.ctrl_handler = &coil->ctrls;202 203 return 0;204}205 206/*207 * V4L2 subdev operations208 */209static int ad5820_registered(struct v4l2_subdev *subdev)210{211 struct ad5820_device *coil = to_ad5820_device(subdev);212 213 return ad5820_init_controls(coil);214}215 216static int217ad5820_set_power(struct v4l2_subdev *subdev, int on)218{219 struct ad5820_device *coil = to_ad5820_device(subdev);220 int ret = 0;221 222 mutex_lock(&coil->power_lock);223 224 /*225 * If the power count is modified from 0 to != 0 or from != 0 to 0,226 * update the power state.227 */228 if (coil->power_count == !on) {229 ret = on ? ad5820_power_on(coil, true) :230 ad5820_power_off(coil, true);231 if (ret < 0)232 goto done;233 }234 235 /* Update the power count. */236 coil->power_count += on ? 1 : -1;237 WARN_ON(coil->power_count < 0);238 239done:240 mutex_unlock(&coil->power_lock);241 return ret;242}243 244static int ad5820_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)245{246 return ad5820_set_power(sd, 1);247}248 249static int ad5820_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)250{251 return ad5820_set_power(sd, 0);252}253 254static const struct v4l2_subdev_core_ops ad5820_core_ops = {255 .s_power = ad5820_set_power,256};257 258static const struct v4l2_subdev_ops ad5820_ops = {259 .core = &ad5820_core_ops,260};261 262static const struct v4l2_subdev_internal_ops ad5820_internal_ops = {263 .registered = ad5820_registered,264 .open = ad5820_open,265 .close = ad5820_close,266};267 268/*269 * I2C driver270 */271static int __maybe_unused ad5820_suspend(struct device *dev)272{273 struct v4l2_subdev *subdev = dev_get_drvdata(dev);274 struct ad5820_device *coil = to_ad5820_device(subdev);275 276 if (!coil->power_count)277 return 0;278 279 return ad5820_power_off(coil, false);280}281 282static int __maybe_unused ad5820_resume(struct device *dev)283{284 struct v4l2_subdev *subdev = dev_get_drvdata(dev);285 struct ad5820_device *coil = to_ad5820_device(subdev);286 287 if (!coil->power_count)288 return 0;289 290 return ad5820_power_on(coil, true);291}292 293static int ad5820_probe(struct i2c_client *client)294{295 struct ad5820_device *coil;296 int ret;297 298 coil = devm_kzalloc(&client->dev, sizeof(*coil), GFP_KERNEL);299 if (!coil)300 return -ENOMEM;301 302 coil->vana = devm_regulator_get(&client->dev, "VANA");303 if (IS_ERR(coil->vana))304 return dev_err_probe(&client->dev, PTR_ERR(coil->vana),305 "could not get regulator for vana\n");306 307 coil->enable_gpio = devm_gpiod_get_optional(&client->dev, "enable",308 GPIOD_OUT_LOW);309 if (IS_ERR(coil->enable_gpio))310 return dev_err_probe(&client->dev, PTR_ERR(coil->enable_gpio),311 "could not get enable gpio\n");312 313 mutex_init(&coil->power_lock);314 315 v4l2_i2c_subdev_init(&coil->subdev, client, &ad5820_ops);316 coil->subdev.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;317 coil->subdev.internal_ops = &ad5820_internal_ops;318 coil->subdev.entity.function = MEDIA_ENT_F_LENS;319 strscpy(coil->subdev.name, "ad5820 focus", sizeof(coil->subdev.name));320 321 ret = media_entity_pads_init(&coil->subdev.entity, 0, NULL);322 if (ret < 0)323 goto clean_mutex;324 325 ret = v4l2_async_register_subdev(&coil->subdev);326 if (ret < 0)327 goto clean_entity;328 329 return ret;330 331clean_entity:332 media_entity_cleanup(&coil->subdev.entity);333clean_mutex:334 mutex_destroy(&coil->power_lock);335 return ret;336}337 338static void ad5820_remove(struct i2c_client *client)339{340 struct v4l2_subdev *subdev = i2c_get_clientdata(client);341 struct ad5820_device *coil = to_ad5820_device(subdev);342 343 v4l2_async_unregister_subdev(&coil->subdev);344 v4l2_ctrl_handler_free(&coil->ctrls);345 media_entity_cleanup(&coil->subdev.entity);346 mutex_destroy(&coil->power_lock);347}348 349static const struct i2c_device_id ad5820_id_table[] = {350 { "ad5820" },351 { "ad5821" },352 { }353};354MODULE_DEVICE_TABLE(i2c, ad5820_id_table);355 356static const struct of_device_id ad5820_of_table[] = {357 { .compatible = "adi,ad5820" },358 { .compatible = "adi,ad5821" },359 { }360};361MODULE_DEVICE_TABLE(of, ad5820_of_table);362 363static SIMPLE_DEV_PM_OPS(ad5820_pm, ad5820_suspend, ad5820_resume);364 365static struct i2c_driver ad5820_i2c_driver = {366 .driver = {367 .name = "ad5820",368 .pm = &ad5820_pm,369 .of_match_table = ad5820_of_table,370 },371 .probe = ad5820_probe,372 .remove = ad5820_remove,373 .id_table = ad5820_id_table,374};375 376module_i2c_driver(ad5820_i2c_driver);377 378MODULE_AUTHOR("Tuukka Toivonen");379MODULE_DESCRIPTION("AD5820 camera lens driver");380MODULE_LICENSE("GPL");381