--- /dev/null
+// 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");
projects / platform / kernel / linux-starfive.git / commitdiff