[PATCH V9 2/2] media: i2c: dw9768: Add DW9768 VCM driver
Dongchun Zhu
dongchun.zhu at mediatek.com
Tue Jun 30 02:22:11 EDT 2020
Add a V4L2 sub-device driver for DW9768 voice coil motor,
providing control to set the desired focus via IIC serial interface.
Signed-off-by: Dongchun Zhu <dongchun.zhu at mediatek.com>
---
MAINTAINERS | 1 +
drivers/media/i2c/Kconfig | 12 +
drivers/media/i2c/Makefile | 1 +
drivers/media/i2c/dw9768.c | 554 +++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 568 insertions(+)
create mode 100644 drivers/media/i2c/dw9768.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 62690c4..35b3dab 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -5221,6 +5221,7 @@ L: linux-media at vger.kernel.org
S: Maintained
T: git git://linuxtv.org/media_tree.git
F: Documentation/devicetree/bindings/media/i2c/dongwoon,dw9768.yaml
+F: drivers/media/i2c/dw9768.c
DONGWOON DW9807 LENS VOICE COIL DRIVER
M: Sakari Ailus <sakari.ailus at linux.intel.com>
diff --git a/drivers/media/i2c/Kconfig b/drivers/media/i2c/Kconfig
index da11036..933371f 100644
--- a/drivers/media/i2c/Kconfig
+++ b/drivers/media/i2c/Kconfig
@@ -1253,6 +1253,18 @@ config VIDEO_DW9714
capability. This is designed for linear control of
voice coil motors, controlled via I2C serial interface.
+config VIDEO_DW9768
+ tristate "DW9768 lens voice coil support"
+ depends on I2C && VIDEO_V4L2
+ select MEDIA_CONTROLLER
+ select VIDEO_V4L2_SUBDEV_API
+ select V4L2_FWNODE
+ help
+ This is a driver for the DW9768 camera lens voice coil.
+ DW9768 is a 10 bit DAC with 100mA output current sink
+ capability. This is designed for linear control of
+ voice coil motors, controlled via I2C serial interface.
+
config VIDEO_DW9807_VCM
tristate "DW9807 lens voice coil support"
depends on I2C && VIDEO_V4L2
diff --git a/drivers/media/i2c/Makefile b/drivers/media/i2c/Makefile
index 993acab..33ad435 100644
--- a/drivers/media/i2c/Makefile
+++ b/drivers/media/i2c/Makefile
@@ -24,6 +24,7 @@ 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-$(CONFIG_VIDEO_DW9768) += dw9768.o
obj-$(CONFIG_VIDEO_DW9807_VCM) += dw9807-vcm.o
obj-$(CONFIG_VIDEO_ADV7170) += adv7170.o
obj-$(CONFIG_VIDEO_ADV7175) += adv7175.o
diff --git a/drivers/media/i2c/dw9768.c b/drivers/media/i2c/dw9768.c
new file mode 100644
index 0000000..45cdd92
--- /dev/null
+++ b/drivers/media/i2c/dw9768.c
@@ -0,0 +1,554 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (c) 2020 MediaTek Inc.
+
+#include <linux/delay.h>
+#include <linux/i2c.h>
+#include <linux/module.h>
+#include <linux/pm_runtime.h>
+#include <linux/regulator/consumer.h>
+#include <media/v4l2-async.h>
+#include <media/v4l2-ctrls.h>
+#include <media/v4l2-device.h>
+#include <media/v4l2-fwnode.h>
+#include <media/v4l2-subdev.h>
+
+#define DW9768_NAME "dw9768"
+#define DW9768_MAX_FOCUS_POS (1024 - 1)
+/*
+ * This sets the minimum granularity for the focus positions.
+ * A value of 1 gives maximum accuracy for a desired focus position
+ */
+#define DW9768_FOCUS_STEPS 1
+
+/*
+ * Ring control and Power control register
+ * Bit[1] RING_EN
+ * 0: Direct mode
+ * 1: AAC mode (ringing control mode)
+ * Bit[0] PD
+ * 0: Normal operation mode
+ * 1: Power down mode
+ * DW9768 requires waiting time of Topr after PD reset takes place.
+ */
+#define DW9768_RING_PD_CONTROL_REG 0x02
+#define DW9768_PD_MODE_OFF 0x00
+#define DW9768_PD_MODE_EN BIT(0)
+#define DW9768_AAC_MODE_EN BIT(1)
+
+/*
+ * DW9768 separates two registers to control the VCM position.
+ * One for MSB value, another is LSB value.
+ * DAC_MSB: D[9:8] (ADD: 0x03)
+ * DAC_LSB: D[7:0] (ADD: 0x04)
+ * D[9:0] DAC data input: positive output current = D[9:0] / 1023 * 100[mA]
+ */
+#define DW9768_MSB_ADDR 0x03
+#define DW9768_LSB_ADDR 0x04
+#define DW9768_STATUS_ADDR 0x05
+
+/*
+ * AAC mode control & prescale register
+ * Bit[7:5] Namely AC[2:0], decide the VCM mode and operation time.
+ * 001 AAC2 0.48 x Tvib
+ * 010 AAC3 0.70 x Tvib
+ * 011 AAC4 0.75 x Tvib
+ * 101 AAC8 1.13 x Tvib
+ * Bit[2:0] Namely PRESC[2:0], set the internal clock dividing rate as follow.
+ * 000 2
+ * 001 1
+ * 010 1/2
+ * 011 1/4
+ * 100 8
+ * 101 4
+ */
+#define DW9768_AAC_PRESC_REG 0x06
+#define DW9768_AAC_MODE_SEL_MASK GENMASK(7, 5)
+#define DW9768_CLOCK_PRE_SCALE_SEL_MASK GENMASK(2, 0)
+
+/*
+ * VCM period of vibration register
+ * Bit[5:0] Defined as VCM rising periodic time (Tvib) together with PRESC[2:0]
+ * Tvib = (6.3ms + AACT[5:0] * 0.1ms) * Dividing Rate
+ * Dividing Rate is the internal clock dividing rate that is defined at
+ * PRESCALE register (ADD: 0x06)
+ */
+#define DW9768_AAC_TIME_REG 0x07
+
+/*
+ * DW9768 requires waiting time (delay time) of t_OPR after power-up,
+ * or in the case of PD reset taking place.
+ */
+#define DW9768_T_OPR_US 1000
+#define DW9768_TVIB_MS_BASE10 (64 - 1)
+#define DW9768_AAC_MODE_DEFAULT 2
+#define DW9768_AAC_TIME_DEFAULT 0x20
+#define DW9768_CLOCK_PRE_SCALE_DEFAULT 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 DW9768_MOVE_STEPS 16
+
+static const char * const dw9768_supply_names[] = {
+ "vin", /* Digital I/O power */
+ "vdd", /* Digital core power */
+};
+
+/* dw9768 device structure */
+struct dw9768 {
+ struct regulator_bulk_data supplies[ARRAY_SIZE(dw9768_supply_names)];
+ struct v4l2_ctrl_handler ctrls;
+ struct v4l2_ctrl *focus;
+ struct v4l2_subdev sd;
+
+ u32 aac_mode;
+ u32 aac_timing;
+ u32 clock_presc;
+ u32 move_delay_us;
+};
+
+static inline struct dw9768 *sd_to_dw9768(struct v4l2_subdev *subdev)
+{
+ return container_of(subdev, struct dw9768, sd);
+}
+
+struct regval_list {
+ u8 reg_num;
+ u8 value;
+};
+
+struct dw9768_aac_mode_ot_multi {
+ u32 aac_mode_enum;
+ u32 ot_multi_base100;
+};
+
+struct dw9768_clk_presc_dividing_rate {
+ u32 clk_presc_enum;
+ u32 dividing_rate_base100;
+};
+
+static const struct dw9768_aac_mode_ot_multi aac_mode_ot_multi[] = {
+ {1, 48},
+ {2, 70},
+ {3, 75},
+ {5, 113},
+};
+
+static const struct dw9768_clk_presc_dividing_rate presc_dividing_rate[] = {
+ {0, 200},
+ {1, 100},
+ {2, 50},
+ {3, 25},
+ {4, 800},
+ {5, 400},
+};
+
+static u32 dw9768_find_ot_multi(u32 aac_mode_param)
+{
+ u32 cur_ot_multi_base100 = 70;
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(aac_mode_ot_multi); i++) {
+ if (aac_mode_ot_multi[i].aac_mode_enum == aac_mode_param) {
+ cur_ot_multi_base100 =
+ aac_mode_ot_multi[i].ot_multi_base100;
+ }
+ }
+
+ return cur_ot_multi_base100;
+}
+
+static u32 dw9768_find_dividing_rate(u32 presc_param)
+{
+ u32 cur_clk_dividing_rate_base100 = 100;
+ unsigned int i;
+
+ for (i = 0; i < ARRAY_SIZE(presc_dividing_rate); i++) {
+ if (presc_dividing_rate[i].clk_presc_enum == presc_param) {
+ cur_clk_dividing_rate_base100 =
+ presc_dividing_rate[i].dividing_rate_base100;
+ }
+ }
+
+ return cur_clk_dividing_rate_base100;
+}
+
+/*
+ * DW9768_AAC_PRESC_REG & DW9768_AAC_TIME_REG determine VCM operation time.
+ * For current VCM mode: AAC3, Operation Time would be 0.70 x Tvib.
+ * Tvib = (6.3ms + AACT[5:0] * 0.1MS) * Dividing Rate.
+ * Below is calculation of the operation delay for each step.
+ */
+static inline u32 dw9768_cal_move_delay(u32 aac_mode_param, u32 presc_param,
+ u32 aac_timing_param)
+{
+ u32 Tvib_us;
+ u32 ot_multi_base100;
+ u32 clk_dividing_rate_base100;
+
+ ot_multi_base100 = dw9768_find_ot_multi(aac_mode_param);
+
+ clk_dividing_rate_base100 = dw9768_find_dividing_rate(presc_param);
+
+ Tvib_us = (DW9768_TVIB_MS_BASE10 + aac_timing_param) *
+ clk_dividing_rate_base100;
+
+ return Tvib_us * ot_multi_base100 / 100;
+}
+
+static int dw9768_mod_reg(struct dw9768 *dw9768, u8 reg, u8 mask, u8 val)
+{
+ struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
+ int ret;
+
+ ret = i2c_smbus_read_byte_data(client, reg);
+ if (ret < 0)
+ return ret;
+
+ val = ((unsigned char)ret & ~mask) | (val & mask);
+
+ return i2c_smbus_write_byte_data(client, reg, val);
+}
+
+static int dw9768_set_dac(struct dw9768 *dw9768, u16 val)
+{
+ struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
+
+ /* Write VCM position to registers */
+ return i2c_smbus_write_word_swapped(client, DW9768_MSB_ADDR, val);
+}
+
+static int dw9768_init(struct dw9768 *dw9768)
+{
+ struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
+ int ret, val;
+
+ /* Reset DW9768_RING_PD_CONTROL_REG to default status 0x00 */
+ ret = i2c_smbus_write_byte_data(client, DW9768_RING_PD_CONTROL_REG,
+ DW9768_PD_MODE_OFF);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * DW9769 requires waiting delay time of t_OPR
+ * after PD reset takes place.
+ */
+ usleep_range(DW9768_T_OPR_US, DW9768_T_OPR_US + 100);
+
+ /* Set DW9768_RING_PD_CONTROL_REG to DW9768_AAC_MODE_EN(0x01) */
+ ret = i2c_smbus_write_byte_data(client, DW9768_RING_PD_CONTROL_REG,
+ DW9768_AAC_MODE_EN);
+ if (ret < 0)
+ return ret;
+
+ /* Set AAC mode */
+ ret = dw9768_mod_reg(dw9768, DW9768_AAC_PRESC_REG,
+ DW9768_AAC_MODE_SEL_MASK,
+ dw9768->aac_mode << 5);
+ if (ret < 0)
+ return ret;
+
+ /* Set clock presc */
+ if (dw9768->clock_presc != DW9768_CLOCK_PRE_SCALE_DEFAULT) {
+ ret = dw9768_mod_reg(dw9768, DW9768_AAC_PRESC_REG,
+ DW9768_CLOCK_PRE_SCALE_SEL_MASK,
+ dw9768->clock_presc);
+ if (ret < 0)
+ return ret;
+ }
+
+ /* Set AAC Timing */
+ if (dw9768->aac_timing != DW9768_AAC_TIME_DEFAULT) {
+ ret = i2c_smbus_write_byte_data(client, DW9768_AAC_TIME_REG,
+ dw9768->aac_timing);
+ if (ret < 0)
+ return ret;
+ }
+
+ for (val = dw9768->focus->val % DW9768_MOVE_STEPS;
+ val <= dw9768->focus->val;
+ val += DW9768_MOVE_STEPS) {
+ ret = dw9768_set_dac(dw9768, val);
+ if (ret) {
+ dev_err(&client->dev, "I2C failure: %d", ret);
+ return ret;
+ }
+ usleep_range(dw9768->move_delay_us,
+ dw9768->move_delay_us + 1000);
+ }
+
+ return 0;
+}
+
+static int dw9768_release(struct dw9768 *dw9768)
+{
+ struct i2c_client *client = v4l2_get_subdevdata(&dw9768->sd);
+ int ret, val;
+
+ val = round_down(dw9768->focus->val, DW9768_MOVE_STEPS);
+ for ( ; val >= 0; val -= DW9768_MOVE_STEPS) {
+ ret = dw9768_set_dac(dw9768, val);
+ if (ret) {
+ dev_err(&client->dev, "I2C write fail: %d", ret);
+ return ret;
+ }
+ usleep_range(dw9768->move_delay_us,
+ dw9768->move_delay_us + 1000);
+ }
+
+ ret = i2c_smbus_write_byte_data(client, DW9768_RING_PD_CONTROL_REG,
+ DW9768_PD_MODE_EN);
+ if (ret < 0)
+ return ret;
+
+ /*
+ * DW9769 requires waiting delay time of t_OPR
+ * after PD reset takes place.
+ */
+ usleep_range(DW9768_T_OPR_US, DW9768_T_OPR_US + 100);
+
+ return 0;
+}
+
+static int dw9768_runtime_suspend(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct v4l2_subdev *sd = i2c_get_clientdata(client);
+ struct dw9768 *dw9768 = sd_to_dw9768(sd);
+
+ dw9768_release(dw9768);
+ regulator_bulk_disable(ARRAY_SIZE(dw9768_supply_names),
+ dw9768->supplies);
+
+ return 0;
+}
+
+static int dw9768_runtime_resume(struct device *dev)
+{
+ struct i2c_client *client = to_i2c_client(dev);
+ struct v4l2_subdev *sd = i2c_get_clientdata(client);
+ struct dw9768 *dw9768 = sd_to_dw9768(sd);
+ int ret;
+
+ ret = regulator_bulk_enable(ARRAY_SIZE(dw9768_supply_names),
+ dw9768->supplies);
+ if (ret < 0) {
+ dev_err(dev, "failed to enable regulators\n");
+ return ret;
+ }
+
+ /*
+ * The datasheet refers to t_OPR that needs to be waited before sending
+ * I2C commands after power-up.
+ */
+ usleep_range(DW9768_T_OPR_US, DW9768_T_OPR_US + 100);
+
+ ret = dw9768_init(dw9768);
+ if (ret < 0)
+ goto disable_regulator;
+
+ return 0;
+
+disable_regulator:
+ regulator_bulk_disable(ARRAY_SIZE(dw9768_supply_names),
+ dw9768->supplies);
+
+ return ret;
+}
+
+static int dw9768_set_ctrl(struct v4l2_ctrl *ctrl)
+{
+ struct dw9768 *dw9768 = container_of(ctrl->handler,
+ struct dw9768, ctrls);
+
+ if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE)
+ return dw9768_set_dac(dw9768, ctrl->val);
+
+ return 0;
+}
+
+static const struct v4l2_ctrl_ops dw9768_ctrl_ops = {
+ .s_ctrl = dw9768_set_ctrl,
+};
+
+static int dw9768_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 dw9768_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh)
+{
+ pm_runtime_put(sd->dev);
+
+ return 0;
+}
+
+static const struct v4l2_subdev_internal_ops dw9768_int_ops = {
+ .open = dw9768_open,
+ .close = dw9768_close,
+};
+
+static const struct v4l2_subdev_ops dw9768_ops = { };
+
+static int dw9768_init_controls(struct dw9768 *dw9768)
+{
+ struct v4l2_ctrl_handler *hdl = &dw9768->ctrls;
+ const struct v4l2_ctrl_ops *ops = &dw9768_ctrl_ops;
+
+ v4l2_ctrl_handler_init(hdl, 1);
+
+ dw9768->focus = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE, 0,
+ DW9768_MAX_FOCUS_POS,
+ DW9768_FOCUS_STEPS, 0);
+
+ if (hdl->error)
+ return hdl->error;
+
+ dw9768->sd.ctrl_handler = hdl;
+
+ return 0;
+}
+
+static int dw9768_probe(struct i2c_client *client)
+{
+ struct device *dev = &client->dev;
+ struct dw9768 *dw9768;
+ unsigned int i;
+ int ret;
+
+ dw9768 = devm_kzalloc(dev, sizeof(*dw9768), GFP_KERNEL);
+ if (!dw9768)
+ return -ENOMEM;
+
+ /* Initialize subdev */
+ v4l2_i2c_subdev_init(&dw9768->sd, client, &dw9768_ops);
+
+ dw9768->aac_mode = DW9768_AAC_MODE_DEFAULT;
+ dw9768->aac_timing = DW9768_AAC_TIME_DEFAULT;
+ dw9768->clock_presc = DW9768_CLOCK_PRE_SCALE_DEFAULT;
+
+ /* Optional indication of AAC mode select */
+ fwnode_property_read_u32(dev_fwnode(dev), "dongwoon,aac-mode",
+ &dw9768->aac_mode);
+
+ /* Optional indication of clock pre-scale select */
+ fwnode_property_read_u32(dev_fwnode(dev), "dongwoon,clock-presc",
+ &dw9768->clock_presc);
+
+ /* Optional indication of AAC Timing */
+ fwnode_property_read_u32(dev_fwnode(dev), "dongwoon,aac-timing",
+ &dw9768->aac_timing);
+
+ dw9768->move_delay_us = dw9768_cal_move_delay(dw9768->aac_mode,
+ dw9768->clock_presc,
+ dw9768->aac_timing);
+
+ for (i = 0; i < ARRAY_SIZE(dw9768_supply_names); i++)
+ dw9768->supplies[i].supply = dw9768_supply_names[i];
+
+ ret = devm_regulator_bulk_get(dev, ARRAY_SIZE(dw9768_supply_names),
+ dw9768->supplies);
+ if (ret) {
+ dev_err(dev, "failed to get regulators\n");
+ return ret;
+ }
+
+ /* Initialize controls */
+ ret = dw9768_init_controls(dw9768);
+ if (ret)
+ goto err_free_handler;
+
+ /* Initialize subdev */
+ dw9768->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE;
+ dw9768->sd.internal_ops = &dw9768_int_ops;
+
+ ret = media_entity_pads_init(&dw9768->sd.entity, 0, NULL);
+ if (ret < 0)
+ goto err_free_handler;
+
+ dw9768->sd.entity.function = MEDIA_ENT_F_LENS;
+
+ pm_runtime_enable(dev);
+ if (!pm_runtime_enabled(dev)) {
+ ret = dw9768_runtime_resume(dev);
+ if (ret < 0) {
+ dev_err(dev, "failed to power on: %d\n", ret);
+ goto err_clean_entity;
+ }
+ }
+
+ ret = v4l2_async_register_subdev(&dw9768->sd);
+ if (ret < 0) {
+ dev_err(dev, "failed to register V4L2 subdev: %d", ret);
+ goto err_power_off;
+ }
+
+ return 0;
+
+err_power_off:
+ if (pm_runtime_enabled(dev))
+ pm_runtime_disable(dev);
+ else
+ dw9768_runtime_suspend(dev);
+err_clean_entity:
+ media_entity_cleanup(&dw9768->sd.entity);
+err_free_handler:
+ v4l2_ctrl_handler_free(&dw9768->ctrls);
+
+ return ret;
+}
+
+static int dw9768_remove(struct i2c_client *client)
+{
+ struct v4l2_subdev *sd = i2c_get_clientdata(client);
+ struct dw9768 *dw9768 = sd_to_dw9768(sd);
+
+ v4l2_async_unregister_subdev(&dw9768->sd);
+ v4l2_ctrl_handler_free(&dw9768->ctrls);
+ media_entity_cleanup(&dw9768->sd.entity);
+ pm_runtime_disable(&client->dev);
+ if (!pm_runtime_status_suspended(&client->dev))
+ dw9768_runtime_suspend(&client->dev);
+ pm_runtime_set_suspended(&client->dev);
+
+ return 0;
+}
+
+static const struct of_device_id dw9768_of_table[] = {
+ { .compatible = "dongwoon,dw9768" },
+ { .compatible = "giantec,gt9769" },
+ {}
+};
+MODULE_DEVICE_TABLE(of, dw9768_of_table);
+
+static const struct dev_pm_ops dw9768_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ SET_RUNTIME_PM_OPS(dw9768_runtime_suspend, dw9768_runtime_resume, NULL)
+};
+
+static struct i2c_driver dw9768_i2c_driver = {
+ .driver = {
+ .name = DW9768_NAME,
+ .pm = &dw9768_pm_ops,
+ .of_match_table = dw9768_of_table,
+ },
+ .probe_new = dw9768_probe,
+ .remove = dw9768_remove,
+};
+module_i2c_driver(dw9768_i2c_driver);
+
+MODULE_AUTHOR("Dongchun Zhu <dongchun.zhu at mediatek.com>");
+MODULE_DESCRIPTION("DW9768 VCM driver");
+MODULE_LICENSE("GPL v2");
--
2.9.2
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