From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from nblzone-211-213.nblnetworks.fi ([83.145.211.213]:36032 "EHLO hillosipuli.retiisi.org.uk" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752924AbdEHUzh (ORCPT ); Mon, 8 May 2017 16:55:37 -0400 Date: Mon, 8 May 2017 23:55:03 +0300 From: Sakari Ailus To: rajmohan.mani@intel.com Cc: linux-media@vger.kernel.org, mchehab@kernel.org Subject: Re: [PATCH] dw9714: Initial driver for dw9714 VCM Message-ID: <20170508205503.GL7456@valkosipuli.retiisi.org.uk> References: <1494156804-9784-1-git-send-email-rajmohan.mani@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1494156804-9784-1-git-send-email-rajmohan.mani@intel.com> Sender: linux-media-owner@vger.kernel.org List-ID: Hi Rajmohan, A few comments below... On Sun, May 07, 2017 at 04:33:24AM -0700, rajmohan.mani@intel.com wrote: > From: Rajmohan Mani > > DW9714 is a 10 bit DAC, designed for linear > control of voice coil motor. > > This driver creates a V4L2 subdevice and > provides control to set the desired focus. > > Signed-off-by: Rajmohan Mani > --- > drivers/media/i2c/Kconfig | 9 ++ > drivers/media/i2c/Makefile | 1 + > drivers/media/i2c/dw9714.c | 333 +++++++++++++++++++++++++++++++++++++++++++++ > 3 files changed, 343 insertions(+) > create mode 100644 drivers/media/i2c/dw9714.c > > diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig > index fd181c9..4f0a7ad 100644 > --- a/drivers/media/i2c/Kconfig > +++ b/drivers/media/i2c/Kconfig > @@ -300,6 +300,15 @@ 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_DW9714 > + tristate "DW9714 lens voice coil support" > + depends on I2C && VIDEO_V4L2 && MEDIA_CONTROLLER You should also depend on VIDEO_V4L2_SUBDEV_API . > + ---help--- > + This is a driver for the DW9714 camera lens voice coil. > + DW9714 is a 10 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_SAA7110 > tristate "Philips SAA7110 video decoder" > depends on VIDEO_V4L2 && I2C > diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile > index 62323ec..987bd1f 100644 > --- a/drivers/media/i2c/Makefile > +++ b/drivers/media/i2c/Makefile > @@ -21,6 +21,7 @@ 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-$(CONFIG_VIDEO_DW9714) += dw9714.o > obj-$(CONFIG_VIDEO_ADV7170) += adv7170.o > obj-$(CONFIG_VIDEO_ADV7175) += adv7175.o > obj-$(CONFIG_VIDEO_ADV7180) += adv7180.o > diff --git a/drivers/media/i2c/dw9714.c b/drivers/media/i2c/dw9714.c > new file mode 100644 > index 0000000..276d3f2 > --- /dev/null > +++ b/drivers/media/i2c/dw9714.c > @@ -0,0 +1,333 @@ > +/* > + * Copyright (c) 2015--2017 Intel Corporation. > + * > + * This program is free software; you can redistribute it and/or > + * modify it under the terms of the GNU General Public License version > + * 2 as published by the Free Software Foundation. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU General Public License for more details. > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#define DW9714_NAME "dw9714" > +#define DW9714_MAX_FOCUS_POS 1023 > +#define DW9714_CTRL_STEPS 16 /* Keep this value power of 2 */ > +#define DW9714_CTRL_DELAY_US 1000 > +/* > + * S[3:2] = 0x00, codes per step for "Linear Slope Control" > + * S[1:0] = 0x00, step period > + */ > +#define DW9714_DEFAULT_S 0x0 > +#define DW9714_VAL(data, s) (u16)((data) << 4 | (s)) > + > +/* dw9714 device structure */ > +struct dw9714_device { > + struct i2c_client *client; > + struct v4l2_ctrl_handler ctrls_vcm; > + struct v4l2_subdev sd; > + u16 current_val; > +}; > + > +#define to_dw9714_vcm(_ctrl) \ > + container_of(_ctrl->handler, struct dw9714_device, ctrls_vcm) > + > +static int dw9714_i2c_write(struct i2c_client *client, u16 data) > +{ > + const int num_msg = 1; > + int ret; > + u16 val = cpu_to_be16(data); > + struct i2c_msg msg = { > + .addr = client->addr, > + .flags = 0, > + .len = sizeof(val), > + .buf = (u8 *) &val, > + }; > + > + ret = i2c_transfer(client->adapter, &msg, num_msg); > + > + /*One retry */ > + if (ret != num_msg) > + ret = i2c_transfer(client->adapter, &msg, num_msg); > + > + if (ret != num_msg) { > + dev_err(&client->dev, "I2C write fail fail\n"); > + return -EIO; > + } else { > + return 0; > + } > +} > + > +static int dw9714_t_focus_vcm(struct dw9714_device *dw9714_dev, u16 val) > +{ > + struct i2c_client *client = dw9714_dev->client; > + int ret = -EINVAL; > + > + dev_dbg(&client->dev, "Setting new value VCM: %d\n", val); > + dw9714_dev->current_val = val; > + > + ret = dw9714_i2c_write(client, DW9714_VAL(val, DW9714_DEFAULT_S)); > + return ret; > +} > + > +static int dw9714_set_ctrl(struct v4l2_ctrl *ctrl) > +{ > + struct dw9714_device *dev_vcm = to_dw9714_vcm(ctrl); > + > + if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE) > + return dw9714_t_focus_vcm(dev_vcm, ctrl->val); > + else > + return -EINVAL; > +} > + > +static const struct v4l2_ctrl_ops dw9714_vcm_ctrl_ops = { > + .s_ctrl = dw9714_set_ctrl, > +}; > + > +static int dw9714_init_controls(struct dw9714_device *dev_vcm) > +{ > + struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm; > + const struct v4l2_ctrl_ops *ops = &dw9714_vcm_ctrl_ops; > + struct i2c_client *client = dev_vcm->client; > + > + v4l2_ctrl_handler_init(hdl, 1); > + > + v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE, > + 0, DW9714_MAX_FOCUS_POS, 1, 0); > + > + if (hdl->error) > + dev_err(&client->dev, "dw9714_init_controls fail\n"); > + dev_vcm->sd.ctrl_handler = hdl; > + return hdl->error; > +} > + > +static void dw9714_subdev_cleanup(struct dw9714_device *dw9714_dev) > +{ > + v4l2_ctrl_handler_free(&dw9714_dev->ctrls_vcm); Please release the control handler after unregistering the sub-device. > + v4l2_async_unregister_subdev(&dw9714_dev->sd); > + v4l2_device_unregister_subdev(&dw9714_dev->sd); > + media_entity_cleanup(&dw9714_dev->sd.entity); > +} > + > +static int dw9714_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) > +{ > + struct dw9714_device *dw9714_dev = container_of(sd, > + struct dw9714_device, > + sd); > + struct device *dev = &dw9714_dev->client->dev; > + int rval; > + > + rval = pm_runtime_get_sync(dev); If this fails you'll need to do pm_runtime_put(dev); > + dev_dbg(dev, "%s rval = %d\n", __func__, rval); > + > + return rval; > +} > + > +static int dw9714_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) > +{ > + struct dw9714_device *dw9714_dev = container_of(sd, > + struct dw9714_device, > + sd); > + struct device *dev = &dw9714_dev->client->dev; > + > + dev_dbg(dev, "%s\n", __func__); > + pm_runtime_put(dev); > + > + return 0; > +} > + > +static const struct v4l2_subdev_internal_ops dw9714_int_ops = { > + .open = dw9714_open, > + .close = dw9714_close, > +}; > + > +static const struct v4l2_subdev_ops dw9714_ops = { }; You should use v4l2_subdev_internal_ops here. > + > +static int dw9714_probe(struct i2c_client *client, > + const struct i2c_device_id *devid) > +{ > + struct dw9714_device *dw9714_dev; > + int rval; > + > + dw9714_dev = devm_kzalloc(&client->dev, sizeof(*dw9714_dev), > + GFP_KERNEL); > + > + if (dw9714_dev == NULL) > + return -ENOMEM; > + > + dw9714_dev->client = client; > + > + v4l2_i2c_subdev_init(&dw9714_dev->sd, client, &dw9714_ops); > + dw9714_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE; > + dw9714_dev->sd.internal_ops = &dw9714_int_ops; > + > + snprintf(dw9714_dev->sd.name, > + sizeof(dw9714_dev->sd.name), > + DW9714_NAME " %d-%4.4x", i2c_adapter_id(client->adapter), > + client->addr); > + > + rval = dw9714_init_controls(dw9714_dev); > + if (rval) > + goto err_cleanup; > + > + rval = media_entity_pads_init(&dw9714_dev->sd.entity, 0, NULL); > + if (rval < 0) > + goto err_cleanup; > + > + dw9714_dev->sd.entity.function = MEDIA_ENT_F_LENS; > + > + rval = v4l2_async_register_subdev(&dw9714_dev->sd); > + if (rval < 0) > + goto err_cleanup; > + > + pm_runtime_enable(&client->dev); Getting PM runtime right doesn't seem to be easy. :-I pm_runtime_enable() alone doesn't do the trick. I wonder if adding pm_runtime_suspend() would do the trick. > + > + return 0; > + > +err_cleanup: > + dw9714_subdev_cleanup(dw9714_dev); > + dev_err(&client->dev, "Probe failed: %d\n", rval); > + return rval; > +} > + > +static int dw9714_remove(struct i2c_client *client) > +{ > + struct v4l2_subdev *sd = i2c_get_clientdata(client); > + struct dw9714_device *dw9714_dev = container_of(sd, > + struct dw9714_device, > + sd); > + > + pm_runtime_disable(&client->dev); > + dw9714_subdev_cleanup(dw9714_dev); > + > + return 0; > +} > + > +#ifdef CONFIG_PM > + > +static int dw9714_runtime_suspend(struct device *dev) > +{ > + return 0; > +} > + > +static int dw9714_runtime_resume(struct device *dev) > +{ > + return 0; I think it'd be fine to remove empty callbacks. > +} > + > +/* This function sets the vcm position, so it consumes least current */ > +static int dw9714_suspend(struct device *dev) > +{ > + struct i2c_client *client = to_i2c_client(dev); > + struct v4l2_subdev *sd = i2c_get_clientdata(client); > + struct dw9714_device *dw9714_dev = container_of(sd, > + struct dw9714_device, > + sd); > + int ret, val; > + > + dev_dbg(dev, "%s\n", __func__); > + > + for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1); > + val >= 0; val -= DW9714_CTRL_STEPS) { > + ret = dw9714_i2c_write(client, > + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); > + if (ret) > + dev_err(dev, "%s I2C failure: %d", __func__, ret); > + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); > + } > + return 0; > +} > + > +/* > + * This function sets the vcm position, so the focus position is set > + * closer to the camera > + */ > +static int dw9714_resume(struct device *dev) > +{ > + struct i2c_client *client = to_i2c_client(dev); > + struct v4l2_subdev *sd = i2c_get_clientdata(client); > + struct dw9714_device *dw9714_dev = container_of(sd, > + struct dw9714_device, > + sd); > + int ret, val; > + > + dev_dbg(dev, "%s\n", __func__); > + > + for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS; > + val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1; > + val += DW9714_CTRL_STEPS) { > + ret = dw9714_i2c_write(client, > + DW9714_VAL((u16) val, DW9714_DEFAULT_S)); > + if (ret) > + dev_err(dev, "%s I2C failure: %d", __func__, ret); > + usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10); > + } > + > + /* restore v4l2 control values */ > + ret = v4l2_ctrl_handler_setup(&dw9714_dev->ctrls_vcm); Doesn't this need to be done for runtime_resume as well? > + dev_dbg(dev, "%s ret = %d\n", __func__, ret); > + return ret; > +} > + > +#else > + > +#define dw9714_suspend NULL > +#define dw9714_resume NULL > +#define dw9714_runtime_suspend NULL > +#define dw9714_runtime_resume NULL > + > +#endif /* CONFIG_PM */ > + > +#ifdef CONFIG_ACPI > +static const struct acpi_device_id dw9714_acpi_match[] = { > + {"DW9714", 0}, > + {}, > +}; > +MODULE_DEVICE_TABLE(acpi, dw9714_acpi_match); > +#endif > + > +static const struct i2c_device_id dw9714_id_table[] = { > + {DW9714_NAME, 0}, > + {} > +}; > + > +MODULE_DEVICE_TABLE(i2c, dw9714_id_table); > + > +static const struct dev_pm_ops dw9714_pm_ops = { > + .suspend = dw9714_suspend, > + .resume = dw9714_resume, > + .runtime_suspend = dw9714_runtime_suspend, > + .runtime_resume = dw9714_runtime_resume, > +}; > + > +static struct i2c_driver dw9714_i2c_driver = { > + .driver = { > + .name = DW9714_NAME, > + .pm = &dw9714_pm_ops, > +#ifdef CONFIG_ACPI > + .acpi_match_table = ACPI_PTR(dw9714_acpi_match), > +#endif > + }, > + .probe = dw9714_probe, > + .remove = dw9714_remove, > + .id_table = dw9714_id_table, > +}; > + > +module_i2c_driver(dw9714_i2c_driver); > + > +MODULE_AUTHOR("Tianshu Qiu "); > +MODULE_AUTHOR("Jian Xu Zheng "); > +MODULE_AUTHOR("Yuning Pu "); > +MODULE_AUTHOR("Jouni Ukkonen "); > +MODULE_AUTHOR("Tommi Franttila "); > +MODULE_DESCRIPTION("DW9714 VCM driver"); > +MODULE_LICENSE("GPL"); -- Regards, Sakari Ailus e-mail: sakari.ailus@iki.fi XMPP: sailus@retiisi.org.uk