[media] V4L2: soc-camera: fix requesting regulators in synchronous case

With synchronous subdevice probing regulators should be requested by the
soc-camera core in soc_camera_pdrv_probe(). Subdevice drivers, supporting
asynchronous probing, call soc_camera_power_init() to request regulators.
Erroneously, the same regulator array is used in the latter case as in
the former, which leads to a failure. This patch fixes it by preventing
the second regulator request from being executed.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>

diff --git a/drivers/media/platform/soc_camera/soc_camera.c b/drivers/media/platform/soc_camera/soc_camera.c
index dc1b26c..387a232 100644 (file)
--- a/drivers/media/platform/soc_camera/soc_camera.c
+++ b/drivers/media/platform/soc_camera/soc_camera.c
@@ -136,7 +136,7 @@ EXPORT_SYMBOL(soc_camera_power_off);
 
 int soc_camera_power_init(struct device *dev, struct soc_camera_subdev_desc *ssdd)
 {
-
+       /* Should not have any effect in synchronous case */
        return devm_regulator_bulk_get(dev, ssdd->num_regulators,
                                       ssdd->regulators);
 }
@@ -1311,6 +1311,7 @@ eusrfmt:
 static int soc_camera_i2c_init(struct soc_camera_device *icd,
                               struct soc_camera_desc *sdesc)
 {
+       struct soc_camera_subdev_desc *ssdd;
        struct i2c_client *client;
        struct soc_camera_host *ici;
        struct soc_camera_host_desc *shd = &sdesc->host_desc;
@@ -1333,7 +1334,21 @@ static int soc_camera_i2c_init(struct soc_camera_device *icd,
                return -ENODEV;
        }
 
-       shd->board_info->platform_data = &sdesc->subdev_desc;
+       ssdd = kzalloc(sizeof(*ssdd), GFP_KERNEL);
+       if (!ssdd) {
+               ret = -ENOMEM;
+               goto ealloc;
+       }
+
+       memcpy(ssdd, &sdesc->subdev_desc, sizeof(*ssdd));
+       /*
+        * In synchronous case we request regulators ourselves in
+        * soc_camera_pdrv_probe(), make sure the subdevice driver doesn't try
+        * to allocate them again.
+        */
+       ssdd->num_regulators = 0;
+       ssdd->regulators = NULL;
+       shd->board_info->platform_data = ssdd;
 
        snprintf(clk_name, sizeof(clk_name), "%d-%04x",
                 shd->i2c_adapter_id, shd->board_info->addr);
@@ -1359,8 +1374,10 @@ static int soc_camera_i2c_init(struct soc_camera_device *icd,
        return 0;
 ei2cnd:
        v4l2_clk_unregister(icd->clk);
-eclkreg:
        icd->clk = NULL;
+eclkreg:
+       kfree(ssdd);
+ealloc:
        i2c_put_adapter(adap);
        return ret;
 }
@@ -1370,15 +1387,18 @@ static void soc_camera_i2c_free(struct soc_camera_device *icd)
        struct i2c_client *client =
                to_i2c_client(to_soc_camera_control(icd));
        struct i2c_adapter *adap;
+       struct soc_camera_subdev_desc *ssdd;
 
        icd->control = NULL;
        if (icd->sasc)
                return;
 
        adap = client->adapter;
+       ssdd = client->dev.platform_data;
        v4l2_device_unregister_subdev(i2c_get_clientdata(client));
        i2c_unregister_device(client);
        i2c_put_adapter(adap);
+       kfree(ssdd);
        v4l2_clk_unregister(icd->clk);
        icd->clk = NULL;
 }
@@ -1995,9 +2015,10 @@ static int soc_camera_pdrv_probe(struct platform_device *pdev)
 
        /*
         * In the asynchronous case ssdd->num_regulators == 0 yet, so, the below
-        * regulator allocation is a dummy. They will be really requested later
-        * in soc_camera_async_bind(). Also note, that in that case regulators
-        * are attached to the I2C device and not to the camera platform device.
+        * regulator allocation is a dummy. They are actually requested by the
+        * subdevice driver, using soc_camera_power_init(). Also note, that in
+        * that case regulators are attached to the I2C device and not to the
+        * camera platform device.
         */
        ret = devm_regulator_bulk_get(&pdev->dev, ssdd->num_regulators,
                                      ssdd->regulators);