media: i2c: dw9714: add optional regulator support

Allow the dw9714 to control a regulator and adjust suspend() and resume()
to support both runtime and system pm.

Signed-off-by: Angus Ainslie <angus@akkea.ca>
Signed-off-by: Martin Kepplinger <martin.kepplinger@puri.sm>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@kernel.org>

diff --git a/drivers/media/i2c/dw9714.c b/drivers/media/i2c/dw9714.c
index 3863dfeb829346ff5cdd0ce2f20e9cad5d37830d..cd7008ad8f2f37764bb55babc90cf87c06496e02 100644 (file)
--- a/drivers/media/i2c/dw9714.c
+++ b/drivers/media/i2c/dw9714.c
@@ -5,6 +5,7 @@
 #include <linux/i2c.h>
 #include <linux/module.h>
 #include <linux/pm_runtime.h>
+#include <linux/regulator/consumer.h>
 #include <media/v4l2-ctrls.h>
 #include <media/v4l2-device.h>
 #include <media/v4l2-event.h>
@@ -36,6 +37,7 @@ struct dw9714_device {
        struct v4l2_ctrl_handler ctrls_vcm;
        struct v4l2_subdev sd;
        u16 current_val;
+       struct regulator *vcc;
 };
 
 static inline struct dw9714_device *to_dw9714_vcm(struct v4l2_ctrl *ctrl)
@@ -145,6 +147,16 @@ static int dw9714_probe(struct i2c_client *client)
        if (dw9714_dev == NULL)
                return -ENOMEM;
 
+       dw9714_dev->vcc = devm_regulator_get(&client->dev, "vcc");
+       if (IS_ERR(dw9714_dev->vcc))
+               return PTR_ERR(dw9714_dev->vcc);
+
+       rval = regulator_enable(dw9714_dev->vcc);
+       if (rval < 0) {
+               dev_err(&client->dev, "failed to enable vcc: %d\n", rval);
+               return rval;
+       }
+
        v4l2_i2c_subdev_init(&dw9714_dev->sd, client, &dw9714_ops);
        dw9714_dev->sd.flags |= V4L2_SUBDEV_FL_HAS_DEVNODE |
                                V4L2_SUBDEV_FL_HAS_EVENTS;
@@ -181,8 +193,18 @@ static int dw9714_remove(struct i2c_client *client)
 {
        struct v4l2_subdev *sd = i2c_get_clientdata(client);
        struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
+       int ret;
 
        pm_runtime_disable(&client->dev);
+       if (!pm_runtime_status_suspended(&client->dev)) {
+               ret = regulator_disable(dw9714_dev->vcc);
+               if (ret) {
+                       dev_err(&client->dev,
+                               "Failed to disable vcc: %d\n", ret);
+                       return ret;
+               }
+       }
+       pm_runtime_set_suspended(&client->dev);
        dw9714_subdev_cleanup(dw9714_dev);
 
        return 0;
@@ -200,6 +222,9 @@ static int __maybe_unused dw9714_vcm_suspend(struct device *dev)
        struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
        int ret, val;
 
+       if (pm_runtime_suspended(&client->dev))
+               return 0;
+
        for (val = dw9714_dev->current_val & ~(DW9714_CTRL_STEPS - 1);
             val >= 0; val -= DW9714_CTRL_STEPS) {
                ret = dw9714_i2c_write(client,
@@ -208,7 +233,12 @@ static int __maybe_unused dw9714_vcm_suspend(struct device *dev)
                        dev_err_once(dev, "%s I2C failure: %d", __func__, ret);
                usleep_range(DW9714_CTRL_DELAY_US, DW9714_CTRL_DELAY_US + 10);
        }
-       return 0;
+
+       ret = regulator_disable(dw9714_dev->vcc);
+       if (ret)
+               dev_err(dev, "Failed to disable vcc: %d\n", ret);
+
+       return ret;
 }
 
 /*
@@ -224,6 +254,16 @@ static int  __maybe_unused dw9714_vcm_resume(struct device *dev)
        struct dw9714_device *dw9714_dev = sd_to_dw9714_vcm(sd);
        int ret, val;
 
+       if (pm_runtime_suspended(&client->dev))
+               return 0;
+
+       ret = regulator_enable(dw9714_dev->vcc);
+       if (ret) {
+               dev_err(dev, "Failed to enable vcc: %d\n", ret);
+               return ret;
+       }
+       usleep_range(1000, 2000);
+
        for (val = dw9714_dev->current_val % DW9714_CTRL_STEPS;
             val < dw9714_dev->current_val + DW9714_CTRL_STEPS - 1;
             val += DW9714_CTRL_STEPS) {