1 // SPDX-License-Identifier: GPL-2.0 2 // Copyright (C) 2018 Intel Corporation 3 4 #include <linux/acpi.h> 5 #include <linux/delay.h> 6 #include <linux/i2c.h> 7 #include <linux/module.h> 8 #include <linux/pm_runtime.h> 9 #include <media/v4l2-ctrls.h> 10 #include <media/v4l2-device.h> 11 12 #define AK7375_MAX_FOCUS_POS 4095 13 /* 14 * This sets the minimum granularity for the focus positions. 15 * A value of 1 gives maximum accuracy for a desired focus position 16 */ 17 #define AK7375_FOCUS_STEPS 1 18 /* 19 * This acts as the minimum granularity of lens movement. 20 * Keep this value power of 2, so the control steps can be 21 * uniformly adjusted for gradual lens movement, with desired 22 * number of control steps. 23 */ 24 #define AK7375_CTRL_STEPS 64 25 #define AK7375_CTRL_DELAY_US 1000 26 27 #define AK7375_REG_POSITION 0x0 28 #define AK7375_REG_CONT 0x2 29 #define AK7375_MODE_ACTIVE 0x0 30 #define AK7375_MODE_STANDBY 0x40 31 32 /* ak7375 device structure */ 33 struct ak7375_device { 34 struct v4l2_ctrl_handler ctrls_vcm; 35 struct v4l2_subdev sd; 36 struct v4l2_ctrl *focus; 37 /* active or standby mode */ 38 bool active; 39 }; 40 41 static inline struct ak7375_device *to_ak7375_vcm(struct v4l2_ctrl *ctrl) 42 { 43 return container_of(ctrl->handler, struct ak7375_device, ctrls_vcm); 44 } 45 46 static inline struct ak7375_device *sd_to_ak7375_vcm(struct v4l2_subdev *subdev) 47 { 48 return container_of(subdev, struct ak7375_device, sd); 49 } 50 51 static int ak7375_i2c_write(struct ak7375_device *ak7375, 52 u8 addr, u16 data, u8 size) 53 { 54 struct i2c_client *client = v4l2_get_subdevdata(&ak7375->sd); 55 u8 buf[3]; 56 int ret; 57 58 if (size != 1 && size != 2) 59 return -EINVAL; 60 buf[0] = addr; 61 buf[size] = data & 0xff; 62 if (size == 2) 63 buf[1] = (data >> 8) & 0xff; 64 ret = i2c_master_send(client, (const char *)buf, size + 1); 65 if (ret < 0) 66 return ret; 67 if (ret != size + 1) 68 return -EIO; 69 70 return 0; 71 } 72 73 static int ak7375_set_ctrl(struct v4l2_ctrl *ctrl) 74 { 75 struct ak7375_device *dev_vcm = to_ak7375_vcm(ctrl); 76 77 if (ctrl->id == V4L2_CID_FOCUS_ABSOLUTE) 78 return ak7375_i2c_write(dev_vcm, AK7375_REG_POSITION, 79 ctrl->val << 4, 2); 80 81 return -EINVAL; 82 } 83 84 static const struct v4l2_ctrl_ops ak7375_vcm_ctrl_ops = { 85 .s_ctrl = ak7375_set_ctrl, 86 }; 87 88 static int ak7375_open(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) 89 { 90 int ret; 91 92 ret = pm_runtime_get_sync(sd->dev); 93 if (ret < 0) { 94 pm_runtime_put_noidle(sd->dev); 95 return ret; 96 } 97 98 return 0; 99 } 100 101 static int ak7375_close(struct v4l2_subdev *sd, struct v4l2_subdev_fh *fh) 102 { 103 pm_runtime_put(sd->dev); 104 105 return 0; 106 } 107 108 static const struct v4l2_subdev_internal_ops ak7375_int_ops = { 109 .open = ak7375_open, 110 .close = ak7375_close, 111 }; 112 113 static const struct v4l2_subdev_ops ak7375_ops = { }; 114 115 static void ak7375_subdev_cleanup(struct ak7375_device *ak7375_dev) 116 { 117 v4l2_async_unregister_subdev(&ak7375_dev->sd); 118 v4l2_ctrl_handler_free(&ak7375_dev->ctrls_vcm); 119 media_entity_cleanup(&ak7375_dev->sd.entity); 120 } 121 122 static int ak7375_init_controls(struct ak7375_device *dev_vcm) 123 { 124 struct v4l2_ctrl_handler *hdl = &dev_vcm->ctrls_vcm; 125 const struct v4l2_ctrl_ops *ops = &ak7375_vcm_ctrl_ops; 126 127 v4l2_ctrl_handler_init(hdl, 1); 128 129 dev_vcm->focus = v4l2_ctrl_new_std(hdl, ops, V4L2_CID_FOCUS_ABSOLUTE, 130 0, AK7375_MAX_FOCUS_POS, AK7375_FOCUS_STEPS, 0); 131 132 if (hdl->error) 133 dev_err(dev_vcm->sd.dev, "%s fail error: 0x%x\n", 134 __func__, hdl->error); 135 dev_vcm->sd.ctrl_handler = hdl; 136 137 return hdl->error; 138 } 139 140 static int ak7375_probe(struct i2c_client *client) 141 { 142 struct ak7375_device *ak7375_dev; 143 int ret; 144 145 ak7375_dev = devm_kzalloc(&client->dev, sizeof(*ak7375_dev), 146 GFP_KERNEL); 147 if (!ak7375_dev) 148 return -ENOMEM; 149 150 v4l2_i2c_subdev_init(&ak7375_dev->sd, client, &ak7375_ops); 151 ak7375_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE; 152 ak7375_dev->sd.internal_ops = &ak7375_int_ops; 153 ak7375_dev->sd.entity.function = MEDIA_ENT_F_LENS; 154 155 ret = ak7375_init_controls(ak7375_dev); 156 if (ret) 157 goto err_cleanup; 158 159 ret = media_entity_pads_init(&ak7375_dev->sd.entity, 0, NULL); 160 if (ret < 0) 161 goto err_cleanup; 162 163 ret = v4l2_async_register_subdev(&ak7375_dev->sd); 164 if (ret < 0) 165 goto err_cleanup; 166 167 pm_runtime_set_active(&client->dev); 168 pm_runtime_enable(&client->dev); 169 pm_runtime_idle(&client->dev); 170 171 return 0; 172 173 err_cleanup: 174 v4l2_ctrl_handler_free(&ak7375_dev->ctrls_vcm); 175 media_entity_cleanup(&ak7375_dev->sd.entity); 176 177 return ret; 178 } 179 180 static int ak7375_remove(struct i2c_client *client) 181 { 182 struct v4l2_subdev *sd = i2c_get_clientdata(client); 183 struct ak7375_device *ak7375_dev = sd_to_ak7375_vcm(sd); 184 185 ak7375_subdev_cleanup(ak7375_dev); 186 pm_runtime_disable(&client->dev); 187 pm_runtime_set_suspended(&client->dev); 188 189 return 0; 190 } 191 192 /* 193 * This function sets the vcm position, so it consumes least current 194 * The lens position is gradually moved in units of AK7375_CTRL_STEPS, 195 * to make the movements smoothly. 196 */ 197 static int __maybe_unused ak7375_vcm_suspend(struct device *dev) 198 { 199 200 struct i2c_client *client = to_i2c_client(dev); 201 struct v4l2_subdev *sd = i2c_get_clientdata(client); 202 struct ak7375_device *ak7375_dev = sd_to_ak7375_vcm(sd); 203 int ret, val; 204 205 if (!ak7375_dev->active) 206 return 0; 207 208 for (val = ak7375_dev->focus->val & ~(AK7375_CTRL_STEPS - 1); 209 val >= 0; val -= AK7375_CTRL_STEPS) { 210 ret = ak7375_i2c_write(ak7375_dev, AK7375_REG_POSITION, 211 val << 4, 2); 212 if (ret) 213 dev_err_once(dev, "%s I2C failure: %d\n", 214 __func__, ret); 215 usleep_range(AK7375_CTRL_DELAY_US, AK7375_CTRL_DELAY_US + 10); 216 } 217 218 ret = ak7375_i2c_write(ak7375_dev, AK7375_REG_CONT, 219 AK7375_MODE_STANDBY, 1); 220 if (ret) 221 dev_err(dev, "%s I2C failure: %d\n", __func__, ret); 222 223 ak7375_dev->active = false; 224 225 return 0; 226 } 227 228 /* 229 * This function sets the vcm position to the value set by the user 230 * through v4l2_ctrl_ops s_ctrl handler 231 * The lens position is gradually moved in units of AK7375_CTRL_STEPS, 232 * to make the movements smoothly. 233 */ 234 static int __maybe_unused ak7375_vcm_resume(struct device *dev) 235 { 236 struct i2c_client *client = to_i2c_client(dev); 237 struct v4l2_subdev *sd = i2c_get_clientdata(client); 238 struct ak7375_device *ak7375_dev = sd_to_ak7375_vcm(sd); 239 int ret, val; 240 241 if (ak7375_dev->active) 242 return 0; 243 244 ret = ak7375_i2c_write(ak7375_dev, AK7375_REG_CONT, 245 AK7375_MODE_ACTIVE, 1); 246 if (ret) { 247 dev_err(dev, "%s I2C failure: %d\n", __func__, ret); 248 return ret; 249 } 250 251 for (val = ak7375_dev->focus->val % AK7375_CTRL_STEPS; 252 val <= ak7375_dev->focus->val; 253 val += AK7375_CTRL_STEPS) { 254 ret = ak7375_i2c_write(ak7375_dev, AK7375_REG_POSITION, 255 val << 4, 2); 256 if (ret) 257 dev_err_ratelimited(dev, "%s I2C failure: %d\n", 258 __func__, ret); 259 usleep_range(AK7375_CTRL_DELAY_US, AK7375_CTRL_DELAY_US + 10); 260 } 261 262 ak7375_dev->active = true; 263 264 return 0; 265 } 266 267 static const struct of_device_id ak7375_of_table[] = { 268 { .compatible = "asahi-kasei,ak7375" }, 269 { /* sentinel */ } 270 }; 271 MODULE_DEVICE_TABLE(of, ak7375_of_table); 272 273 static const struct dev_pm_ops ak7375_pm_ops = { 274 SET_SYSTEM_SLEEP_PM_OPS(ak7375_vcm_suspend, ak7375_vcm_resume) 275 SET_RUNTIME_PM_OPS(ak7375_vcm_suspend, ak7375_vcm_resume, NULL) 276 }; 277 278 static struct i2c_driver ak7375_i2c_driver = { 279 .driver = { 280 .name = "ak7375", 281 .pm = &ak7375_pm_ops, 282 .of_match_table = ak7375_of_table, 283 }, 284 .probe_new = ak7375_probe, 285 .remove = ak7375_remove, 286 }; 287 module_i2c_driver(ak7375_i2c_driver); 288 289 MODULE_AUTHOR("Tianshu Qiu <tian.shu.qiu@intel.com>"); 290 MODULE_AUTHOR("Bingbu Cao <bingbu.cao@intel.com>"); 291 MODULE_DESCRIPTION("AK7375 VCM driver"); 292 MODULE_LICENSE("GPL v2"); 293