On 2018年06月21日 19:23, Sakari Ailus wrote: > Hi Bingbu, > > On Tue, Jun 19, 2018 at 02:01:47PM +0800, bingbu.cao@xxxxxxxxx wrote: >> From: Bingbu Cao <bingbu.cao@xxxxxxxxx> >> >> Add a v4l2 sub-device driver for the ak7375 lens voice coil. >> This is a voice coil module using the i2c bus to control the >> focus position. >> >> ak7375 can write multiple bytes of data at a time. If more >> data is received instead of the stop condition after receiving >> one byte of data, the address inside the chip is automatically >> incremented and the data is written into the next address. >> >> The ak7375 can control the position with 12 bits value and >> consists of two 8 bit registers show as below: >> register 0x00(AK7375_REG_POSITION): >> +---+---+---+---+---+---+---+---+ >> |D11|D10|D09|D08|D07|D06|D05|D04| >> +---+---+---+---+---+---+---+---+ >> register 0x01: >> +---+---+---+---+---+---+---+---+ >> |D03|D02|D01|D00|---|---|---|---| >> +---+---+---+---+---+---+---+---+ >> >> This driver support : >> - set ak7375 to standby mode once suspend and >> turn it back to active if resume >> - set the position via V4L2_CID_FOCUS_ABSOLUTE ctrl >> >> Signed-off-by: Tianshu Qiu <tian.shu.qiu@xxxxxxxxx> >> Signed-off-by: Bingbu Cao <bingbu.cao@xxxxxxxxx> >> Reviewed-by: Sakari Ailus <sakari.ailus@xxxxxxxxxxxxxxx> >> >> --- >> Changes from v1 -> v3: >> - correct i2c write >> - add media_entity_pads_init() into probe >> - move the MAINTAINERs change into dt-binding change >> - correct the compatible stringa >> Changes since v3: >> - add active flag to indicate the mode >> - refine some coding style >> >> This patch is based on Sakari's media-tree git: >> https://git.linuxtv.org/sailus/media_tree.git/log/?h=for-4.18-5 >> --- >> --- >> drivers/media/i2c/Kconfig | 10 ++ >> drivers/media/i2c/Makefile | 1 + >> drivers/media/i2c/ak7375.c | 293 +++++++++++++++++++++++++++++++++++++++++++++ >> 3 files changed, 304 insertions(+) >> create mode 100644 drivers/media/i2c/ak7375.c >> >> diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig >> index 341452fe98df..ff3cb5afb0e1 100644 >> --- a/drivers/media/i2c/Kconfig >> +++ b/drivers/media/i2c/Kconfig >> @@ -326,6 +326,16 @@ config VIDEO_AD5820 >> This is a driver for the AD5820 camera lens voice coil. >> It is used for example in Nokia N900 (RX-51). >> >> +config VIDEO_AK7375 >> + tristate "AK7375 lens voice coil support" >> + depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER >> + depends on VIDEO_V4L2_SUBDEV_API >> + help >> + This is a driver for the AK7375 camera lens voice coil. >> + AK7375 is a 12 bit DAC with 120mA output current sink >> + capability. This is designed for linear control of >> + voice coil motors, controlled via I2C serial interface. >> + >> config VIDEO_DW9714 >> tristate "DW9714 lens voice coil support" >> depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER >> diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile >> index d679d57cd3b3..05b97e319ea9 100644 >> --- a/drivers/media/i2c/Makefile >> +++ b/drivers/media/i2c/Makefile >> @@ -23,6 +23,7 @@ obj-$(CONFIG_VIDEO_SAA7127) += saa7127.o >> obj-$(CONFIG_VIDEO_SAA7185) += saa7185.o >> obj-$(CONFIG_VIDEO_SAA6752HS) += saa6752hs.o >> obj-$(CONFIG_VIDEO_AD5820) += ad5820.o >> +obj-$(CONFIG_VIDEO_AK7375) += ak7375.o >> obj-$(CONFIG_VIDEO_DW9714) += dw9714.o >> obj-$(CONFIG_VIDEO_ADV7170) += adv7170.o >> obj-$(CONFIG_VIDEO_ADV7175) += adv7175.o >> diff --git a/drivers/media/i2c/ak7375.c b/drivers/media/i2c/ak7375.c >> new file mode 100644 >> index 000000000000..9f039513d57f >> --- /dev/null >> +++ b/drivers/media/i2c/ak7375.c >> @@ -0,0 +1,293 @@ >> +// 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 val; > "ret" would seem to be a more appropriate name for this. > > I'll apply the patch with this change if you're fine with that. Fine to me, thanks! > >> + >> + 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; >> + >> + val = ak7375_init_controls(ak7375_dev); >> + if (val) >> + goto err_cleanup; >> + >> + val = media_entity_pads_init(&ak7375_dev->sd.entity, 0, NULL); >> + if (val < 0) >> + goto err_cleanup; >> + >> + val = v4l2_async_register_subdev(&ak7375_dev->sd); >> + if (val < 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); >> + dev_err(&client->dev, "Probe failed: %d\n", val); >> + >> + return val; >> +} >> + >> +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@xxxxxxxxx>"); >> +MODULE_AUTHOR("Bingbu Cao <bingbu.cao@xxxxxxxxx>"); >> +MODULE_DESCRIPTION("AK7375 VCM driver"); >> +MODULE_LICENSE("GPL v2"); >> -- >> 1.9.1 >> -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
