Failing to register with devfreq leaves hba->devfreq assigned, which
causes the error path to dereference the ERR_PTR(). Rather than bolting
on more conditionals, move the call of devm_devfreq_add_device() into
it's own function and only update hba->devfreq once it's successfully
registered.

The subsequent patch builds upon this to make UFS actually work again,
as it's been broken since f1d981eaecf8 ("PM / devfreq: Use the available
min/max frequency")

Also switch to use DEVFREQ_GOV_SIMPLE_ONDEMAND constant.

Reviewed-by: Chanwoo Choi <cw00.c...@samsung.com>
Signed-off-by: Bjorn Andersson <bjorn.anders...@linaro.org>
---

Changes since v2:
- Use DEVFREQ_GOV_SIMPLE_ONDEMAND, per Chanwoo's recommendation
- Picked up Chanwoo's R-b

Changes since v1:
- None

 drivers/scsi/ufs/ufshcd.c | 31 ++++++++++++++++++++++---------
 1 file changed, 22 insertions(+), 9 deletions(-)

diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c
index 00e79057f870..f04902a066cb 100644
--- a/drivers/scsi/ufs/ufshcd.c
+++ b/drivers/scsi/ufs/ufshcd.c
@@ -1287,6 +1287,26 @@ static struct devfreq_dev_profile ufs_devfreq_profile = {
        .get_dev_status = ufshcd_devfreq_get_dev_status,
 };
 
+static int ufshcd_devfreq_init(struct ufs_hba *hba)
+{
+       struct devfreq *devfreq;
+       int ret;
+
+       devfreq = devm_devfreq_add_device(hba->dev,
+                       &ufs_devfreq_profile,
+                       DEVFREQ_GOV_SIMPLE_ONDEMAND,
+                       NULL);
+       if (IS_ERR(devfreq)) {
+               ret = PTR_ERR(devfreq);
+               dev_err(hba->dev, "Unable to register with devfreq %d\n", ret);
+               return ret;
+       }
+
+       hba->devfreq = devfreq;
+
+       return 0;
+}
+
 static void __ufshcd_suspend_clkscaling(struct ufs_hba *hba)
 {
        unsigned long flags;
@@ -6439,16 +6459,9 @@ static int ufshcd_probe_hba(struct ufs_hba *hba)
                                sizeof(struct ufs_pa_layer_attr));
                        hba->clk_scaling.saved_pwr_info.is_valid = true;
                        if (!hba->devfreq) {
-                               hba->devfreq = devm_devfreq_add_device(hba->dev,
-                                                       &ufs_devfreq_profile,
-                                                       "simple_ondemand",
-                                                       NULL);
-                               if (IS_ERR(hba->devfreq)) {
-                                       ret = PTR_ERR(hba->devfreq);
-                                       dev_err(hba->dev, "Unable to register 
with devfreq %d\n",
-                                                       ret);
+                               ret = ufshcd_devfreq_init(hba);
+                               if (ret)
                                        goto out;
-                               }
                        }
                        hba->clk_scaling.is_allowed = true;
                }
-- 
2.17.0

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