// SPDX-License-Identifier: GPL-2.0 // Copyright (C) 2018 Intel Corporation #include <linux/acpi.h> #include <linux/delay.h> #include <linux/i2c.h> #include <linux/module.h> #include <linux/pm_runtime.h> #include <media/v4l2-ctrls.h> #include <media/v4l2-device.h> #define AK7375_MAX_FOCUS_POS 4095 /* * This sets the minimum granularity for the focus positions. * A value of 1 gives maximum accuracy for a desired focus position */ #define AK7375_FOCUS_STEPS 1 /* * This acts as the minimum granularity of lens movement. * Keep this value power of 2, so the control steps can be * uniformly adjusted for gradual lens movement, with desired * number of control steps. */ #define AK7375_CTRL_STEPS 64 #define AK7375_CTRL_DELAY_US 1000 #define AK7375_REG_POSITION 0x0 #define AK7375_REG_CONT 0x2 #define AK7375_MODE_ACTIVE 0x0 #define AK7375_MODE_STANDBY 0x40 /* ak7375 device structure */ struct ak7375_device { struct v4l2_ctrl_handler ctrls_vcm; struct v4l2_subdev sd; struct v4l2_ctrl *focus; /* active or standby mode */ bool active; }; static inline struct ak7375_device *to_ak7375_vcm(struct v4l2_ctrl *ctrl) { return container_of(ctrl->handler, struct ak7375_device, ctrls_vcm); } static inline struct ak7375_device *sd_to_ak7375_vcm(struct v4l2_subdev *subdev) { return container_of(subdev, struct ak7375_device, sd); } static int ak7375_i2c_write(struct ak7375_device *ak7375, u8 addr, u16 data, u8 size) { struct i2c_client *client = v4l2_get_subdevdata(&ak7375->sd); u8 buf[3]; int ret; if (size != 1 && size != 2) return -EINVAL; buf[0] = addr; buf[size] = data & 0xff; if (size == 2) buf[1] = (data >> 8) & 0xff; ret = i2c_master_send(client, (const char *)buf, size + 1); if (ret < 0) return ret; if (ret != size + 1) return -EIO; return 0; } static int ak7375_set_ctrl(struct v4l2_ctrl *ctrl) { struct ak7375_device *dev_vcm = to_ak7375_vcm(ctrl); if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE) return ak7375_i2c_write(dev_vcm, AK7375_REG_POSITION, ctrl->val << 4, 2); return -EINVAL; } static const struct v4l2_ctrl_ops ak7375_vcm_ctrl_ops = { .s_ctrl = ak7375_set_ctrl, }; static int ak7375_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) { int ret; ret = pm_runtime_get_sync(sd->dev); if (ret < 0) { pm_runtime_put_noidle(sd->dev); return ret; } return 0; } static int ak7375_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) { pm_runtime_put(sd->dev); return 0; } static const struct v4l2_subdev_internal_ops ak7375_int_ops = { .open = ak7375_open, .close = ak7375_close, }; static const struct v4l2_subdev_ops ak7375_ops = { }; static void ak7375_subdev_cleanup(struct ak7375_device *ak7375_dev) { v4l2_async_unregister_subdev(&ak7375_dev->sd); v4l2_ctrl_handler_free(&ak7375_dev->ctrls_vcm); media_entity_cleanup(&ak7375_dev->sd.entity); } static int ak7375_init_controls(struct ak7375_device *dev_vcm) { struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm; const struct v4l2_ctrl_ops *ops = &ak7375_vcm_ctrl_ops; v4l2_ctrl_handler_init(hdl, 1); dev_vcm->focus = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE, 0, AK7375_MAX_FOCUS_POS, AK7375_FOCUS_STEPS, 0); if (hdl->error) dev_err(dev_vcm->sd.dev, "%s fail error: 0x%x\n", __func__, hdl->error); dev_vcm->sd.ctrl_handler = hdl; return hdl->error; } static int ak7375_probe(struct i2c_client *client) { struct ak7375_device *ak7375_dev; int ret; ak7375_dev = devm_kzalloc(&client->dev, sizeof(*ak7375_dev), GFP_KERNEL); if (!ak7375_dev) return -ENOMEM; v4l2_i2c_subdev_init(&ak7375_dev->sd, client, &ak7375_ops); ak7375_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE; ak7375_dev->sd.internal_ops = &ak7375_int_ops; ak7375_dev->sd.entity.function = MEDIA_ENT_F_LENS; ret = ak7375_init_controls(ak7375_dev); if (ret) goto err_cleanup; ret = media_entity_pads_init(&ak7375_dev->sd.entity, 0, NULL); if (ret < 0) goto err_cleanup; ret = v4l2_async_register_subdev(&ak7375_dev->sd); if (ret < 0) goto err_cleanup; pm_runtime_set_active(&client->dev); pm_runtime_enable(&client->dev); pm_runtime_idle(&client->dev); return 0; err_cleanup: v4l2_ctrl_handler_free(&ak7375_dev->ctrls_vcm); media_entity_cleanup(&ak7375_dev->sd.entity); return ret; } static int ak7375_remove(struct i2c_client *client) { struct v4l2_subdev *sd = i2c_get_clientdata(client); struct ak7375_device *ak7375_dev = sd_to_ak7375_vcm(sd); ak7375_subdev_cleanup(ak7375_dev); pm_runtime_disable(&client->dev); pm_runtime_set_suspended(&client->dev); return 0; } /* * This function sets the vcm position, so it consumes least current * The lens position is gradually moved in units of AK7375_CTRL_STEPS, * to make the movements smoothly. */ static int __maybe_unused ak7375_vcm_suspend(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); struct v4l2_subdev *sd = i2c_get_clientdata(client); struct ak7375_device *ak7375_dev = sd_to_ak7375_vcm(sd); int ret, val; if (!ak7375_dev->active) return 0; for (val = ak7375_dev->focus->val & ~(AK7375_CTRL_STEPS - 1); val >= 0; val -= AK7375_CTRL_STEPS) { ret = ak7375_i2c_write(ak7375_dev, AK7375_REG_POSITION, val << 4, 2); if (ret) dev_err_once(dev, "%s I2C failure: %d\n", __func__, ret); usleep_range(AK7375_CTRL_DELAY_US, AK7375_CTRL_DELAY_US + 10); } ret = ak7375_i2c_write(ak7375_dev, AK7375_REG_CONT, AK7375_MODE_STANDBY, 1); if (ret) dev_err(dev, "%s I2C failure: %d\n", __func__, ret); ak7375_dev->active = false; return 0; } /* * This function sets the vcm position to the value set by the user * through v4l2_ctrl_ops s_ctrl handler * The lens position is gradually moved in units of AK7375_CTRL_STEPS, * to make the movements smoothly. */ static int __maybe_unused ak7375_vcm_resume(struct device *dev) { struct i2c_client *client = to_i2c_client(dev); struct v4l2_subdev *sd = i2c_get_clientdata(client); struct ak7375_device *ak7375_dev = sd_to_ak7375_vcm(sd); int ret, val; if (ak7375_dev->active) return 0; ret = ak7375_i2c_write(ak7375_dev, AK7375_REG_CONT, AK7375_MODE_ACTIVE, 1); if (ret) { dev_err(dev, "%s I2C failure: %d\n", __func__, ret); return ret; } for (val = ak7375_dev->focus->val % AK7375_CTRL_STEPS; val <= ak7375_dev->focus->val; val += AK7375_CTRL_STEPS) { ret = ak7375_i2c_write(ak7375_dev, AK7375_REG_POSITION, val << 4, 2); if (ret) dev_err_ratelimited(dev, "%s I2C failure: %d\n", __func__, ret); usleep_range(AK7375_CTRL_DELAY_US, AK7375_CTRL_DELAY_US + 10); } ak7375_dev->active = true; return 0; } static const struct of_device_id ak7375_of_table[] = { { .compatible = "asahi-kasei,ak7375" }, { /* sentinel */ } }; MODULE_DEVICE_TABLE(of, ak7375_of_table); static const struct dev_pm_ops ak7375_pm_ops = { SET_SYSTEM_SLEEP_PM_OPS(ak7375_vcm_suspend, ak7375_vcm_resume) SET_RUNTIME_PM_OPS(ak7375_vcm_suspend, ak7375_vcm_resume, NULL) }; static struct i2c_driver ak7375_i2c_driver = { .driver = { .name = "ak7375", .pm = &ak7375_pm_ops, .of_match_table = ak7375_of_table, }, .probe_new = ak7375_probe, .remove = ak7375_remove, }; module_i2c_driver(ak7375_i2c_driver); MODULE_AUTHOR("Tianshu Qiu <tian.shu.qiu@intel.com>"); MODULE_AUTHOR("Bingbu Cao <bingbu.cao@intel.com>"); MODULE_DESCRIPTION("AK7375 VCM driver"); MODULE_LICENSE("GPL v2");