diff options
Diffstat (limited to 'drivers/media/i2c/dw9807-vcm.c')
| -rw-r--r-- | drivers/media/i2c/dw9807-vcm.c | 321 |
1 files changed, 321 insertions, 0 deletions
diff --git a/drivers/media/i2c/dw9807-vcm.c b/drivers/media/i2c/dw9807-vcm.c new file mode 100644 index 0000000000..4148009e0e --- /dev/null +++ b/drivers/media/i2c/dw9807-vcm.c @@ -0,0 +1,321 @@ +// 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/iopoll.h> +#include <linux/module.h> +#include <linux/pm_runtime.h> +#include <media/v4l2-ctrls.h> +#include <media/v4l2-device.h> + +#define DW9807_MAX_FOCUS_POS 1023 +/* + * This sets the minimum granularity for the focus positions. + * A value of 1 gives maximum accuracy for a desired focus position. + */ +#define DW9807_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 DW9807_CTRL_STEPS 16 +#define DW9807_CTRL_DELAY_US 1000 + +#define DW9807_CTL_ADDR 0x02 +/* + * DW9807 separates two registers to control the VCM position. + * One for MSB value, another is LSB value. + */ +#define DW9807_MSB_ADDR 0x03 +#define DW9807_LSB_ADDR 0x04 +#define DW9807_STATUS_ADDR 0x05 +#define DW9807_MODE_ADDR 0x06 +#define DW9807_RESONANCE_ADDR 0x07 + +#define MAX_RETRY 10 + +struct dw9807_device { + struct v4l2_ctrl_handler ctrls_vcm; + struct v4l2_subdev sd; + u16 current_val; +}; + +static inline struct dw9807_device *sd_to_dw9807_vcm( + struct v4l2_subdev *subdev) +{ + return container_of(subdev, struct dw9807_device, sd); +} + +static int dw9807_i2c_check(struct i2c_client *client) +{ + const char status_addr = DW9807_STATUS_ADDR; + char status_result; + int ret; + + ret = i2c_master_send(client, &status_addr, sizeof(status_addr)); + if (ret < 0) { + dev_err(&client->dev, "I2C write STATUS address fail ret = %d\n", + ret); + return ret; + } + + ret = i2c_master_recv(client, &status_result, sizeof(status_result)); + if (ret < 0) { + dev_err(&client->dev, "I2C read STATUS value fail ret = %d\n", + ret); + return ret; + } + + return status_result; +} + +static int dw9807_set_dac(struct i2c_client *client, u16 data) +{ + const char tx_data[3] = { + DW9807_MSB_ADDR, ((data >> 8) & 0x03), (data & 0xff) + }; + int val, ret; + + /* + * According to the datasheet, need to check the bus status before we + * write VCM position. This ensure that we really write the value + * into the register + */ + ret = readx_poll_timeout(dw9807_i2c_check, client, val, val <= 0, + DW9807_CTRL_DELAY_US, MAX_RETRY * DW9807_CTRL_DELAY_US); + + if (ret || val < 0) { + if (ret) { + dev_warn(&client->dev, + "Cannot do the write operation because VCM is busy\n"); + } + + return ret ? -EBUSY : val; + } + + /* Write VCM position to registers */ + ret = i2c_master_send(client, tx_data, sizeof(tx_data)); + if (ret < 0) { + dev_err(&client->dev, + "I2C write MSB fail ret=%d\n", ret); + + return ret; + } + + return 0; +} + +static int dw9807_set_ctrl(struct v4l2_ctrl *ctrl) +{ + struct dw9807_device *dev_vcm = container_of(ctrl->handler, + struct dw9807_device, ctrls_vcm); + + if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE) { + struct i2c_client *client = v4l2_get_subdevdata(&dev_vcm->sd); + + dev_vcm->current_val = ctrl->val; + return dw9807_set_dac(client, ctrl->val); + } + + return -EINVAL; +} + +static const struct v4l2_ctrl_ops dw9807_vcm_ctrl_ops = { + .s_ctrl = dw9807_set_ctrl, +}; + +static int dw9807_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) +{ + return pm_runtime_resume_and_get(sd->dev); +} + +static int dw9807_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) +{ + pm_runtime_put(sd->dev); + + return 0; +} + +static const struct v4l2_subdev_internal_ops dw9807_int_ops = { + .open = dw9807_open, + .close = dw9807_close, +}; + +static const struct v4l2_subdev_ops dw9807_ops = { }; + +static void dw9807_subdev_cleanup(struct dw9807_device *dw9807_dev) +{ + v4l2_async_unregister_subdev(&dw9807_dev->sd); + v4l2_ctrl_handler_free(&dw9807_dev->ctrls_vcm); + media_entity_cleanup(&dw9807_dev->sd.entity); +} + +static int dw9807_init_controls(struct dw9807_device *dev_vcm) +{ + struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm; + const struct v4l2_ctrl_ops *ops = &dw9807_vcm_ctrl_ops; + struct i2c_client *client = v4l2_get_subdevdata(&dev_vcm->sd); + + v4l2_ctrl_handler_init(hdl, 1); + + v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE, + 0, DW9807_MAX_FOCUS_POS, DW9807_FOCUS_STEPS, 0); + + dev_vcm->sd.ctrl_handler = hdl; + if (hdl->error) { + dev_err(&client->dev, "%s fail error: 0x%x\n", + __func__, hdl->error); + return hdl->error; + } + + return 0; +} + +static int dw9807_probe(struct i2c_client *client) +{ + struct dw9807_device *dw9807_dev; + int rval; + + dw9807_dev = devm_kzalloc(&client->dev, sizeof(*dw9807_dev), + GFP_KERNEL); + if (dw9807_dev == NULL) + return -ENOMEM; + + v4l2_i2c_subdev_init(&dw9807_dev->sd, client, &dw9807_ops); + dw9807_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE; + dw9807_dev->sd.internal_ops = &dw9807_int_ops; + + rval = dw9807_init_controls(dw9807_dev); + if (rval) + goto err_cleanup; + + rval = media_entity_pads_init(&dw9807_dev->sd.entity, 0, NULL); + if (rval < 0) + goto err_cleanup; + + dw9807_dev->sd.entity.function = MEDIA_ENT_F_LENS; + + rval = v4l2_async_register_subdev(&dw9807_dev->sd); + if (rval < 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(&dw9807_dev->ctrls_vcm); + media_entity_cleanup(&dw9807_dev->sd.entity); + + return rval; +} + +static void dw9807_remove(struct i2c_client *client) +{ + struct v4l2_subdev *sd = i2c_get_clientdata(client); + struct dw9807_device *dw9807_dev = sd_to_dw9807_vcm(sd); + + pm_runtime_disable(&client->dev); + + dw9807_subdev_cleanup(dw9807_dev); +} + +/* + * This function sets the vcm position, so it consumes least current + * The lens position is gradually moved in units of DW9807_CTRL_STEPS, + * to make the movements smoothly. + */ +static int __maybe_unused dw9807_vcm_suspend(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct v4l2_subdev *sd = i2c_get_clientdata(client); + struct dw9807_device *dw9807_dev = sd_to_dw9807_vcm(sd); + const char tx_data[2] = { DW9807_CTL_ADDR, 0x01 }; + int ret, val; + + for (val = dw9807_dev->current_val & ~(DW9807_CTRL_STEPS - 1); + val >= 0; val -= DW9807_CTRL_STEPS) { + ret = dw9807_set_dac(client, val); + if (ret) + dev_err_once(dev, "%s I2C failure: %d", __func__, ret); + usleep_range(DW9807_CTRL_DELAY_US, DW9807_CTRL_DELAY_US + 10); + } + + /* Power down */ + ret = i2c_master_send(client, tx_data, sizeof(tx_data)); + if (ret < 0) { + dev_err(&client->dev, "I2C write CTL fail ret = %d\n", ret); + return ret; + } + + 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 DW9807_CTRL_STEPS, + * to make the movements smoothly. + */ +static int __maybe_unused dw9807_vcm_resume(struct device *dev) +{ + struct i2c_client *client = to_i2c_client(dev); + struct v4l2_subdev *sd = i2c_get_clientdata(client); + struct dw9807_device *dw9807_dev = sd_to_dw9807_vcm(sd); + const char tx_data[2] = { DW9807_CTL_ADDR, 0x00 }; + int ret, val; + + /* Power on */ + ret = i2c_master_send(client, tx_data, sizeof(tx_data)); + if (ret < 0) { + dev_err(&client->dev, "I2C write CTL fail ret = %d\n", ret); + return ret; + } + + for (val = dw9807_dev->current_val % DW9807_CTRL_STEPS; + val < dw9807_dev->current_val + DW9807_CTRL_STEPS - 1; + val += DW9807_CTRL_STEPS) { + ret = dw9807_set_dac(client, val); + if (ret) + dev_err_ratelimited(dev, "%s I2C failure: %d", + __func__, ret); + usleep_range(DW9807_CTRL_DELAY_US, DW9807_CTRL_DELAY_US + 10); + } + + return 0; +} + +static const struct of_device_id dw9807_of_table[] = { + { .compatible = "dongwoon,dw9807-vcm" }, + /* Compatibility for older firmware, NEVER USE THIS IN FIRMWARE! */ + { .compatible = "dongwoon,dw9807" }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, dw9807_of_table); + +static const struct dev_pm_ops dw9807_pm_ops = { + SET_SYSTEM_SLEEP_PM_OPS(dw9807_vcm_suspend, dw9807_vcm_resume) + SET_RUNTIME_PM_OPS(dw9807_vcm_suspend, dw9807_vcm_resume, NULL) +}; + +static struct i2c_driver dw9807_i2c_driver = { + .driver = { + .name = "dw9807", + .pm = &dw9807_pm_ops, + .of_match_table = dw9807_of_table, + }, + .probe = dw9807_probe, + .remove = dw9807_remove, +}; + +module_i2c_driver(dw9807_i2c_driver); + +MODULE_AUTHOR("Chiang, Alan"); +MODULE_DESCRIPTION("DW9807 VCM driver"); +MODULE_LICENSE("GPL v2"); |