[PATCH 4.19 18/56] Revert "drm/amdgpu: Fix NULL dereference in dpm sysfs handlers"

[Greg Kroah-Hartman]

From: Alex Deucher <alexander.deuc...@amd.com>

commit 87004abfbc27261edd15716515d89ab42198b405 upstream.

This regressed some working configurations so revert it.  Will
fix this properly for 5.9 and backport then.

This reverts commit 38e0c89a19fd13f28d2b4721035160a3e66e270b.

Signed-off-by: Alex Deucher <alexander.deuc...@amd.com>
Cc: sta...@vger.kernel.org
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>

---
 drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c |    9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

--- a/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_pm.c
@@ -529,7 +529,8 @@ static ssize_t amdgpu_set_pp_od_clk_volt
 
        while (isspace(*++tmp_str));
 
-       while ((sub_str = strsep(&tmp_str, delimiter)) != NULL) {
+       while (tmp_str[0]) {
+               sub_str = strsep(&tmp_str, delimiter);
                ret = kstrtol(sub_str, 0, &parameter[parameter_size]);
                if (ret)
                        return -EINVAL;
@@ -629,7 +630,8 @@ static ssize_t amdgpu_read_mask(const ch
        memcpy(buf_cpy, buf, bytes);
        buf_cpy[bytes] = '\0';
        tmp = buf_cpy;
-       while ((sub_str = strsep(&tmp, delimiter)) != NULL) {
+       while (tmp[0]) {
+               sub_str = strsep(&tmp, delimiter);
                if (strlen(sub_str)) {
                        ret = kstrtol(sub_str, 0, &level);
                        if (ret)
@@ -880,7 +882,8 @@ static ssize_t amdgpu_set_pp_power_profi
                        i++;
                memcpy(buf_cpy, buf, count-i);
                tmp_str = buf_cpy;
-               while ((sub_str = strsep(&tmp_str, delimiter)) != NULL) {
+               while (tmp_str[0]) {
+                       sub_str = strsep(&tmp_str, delimiter);
                        ret = kstrtol(sub_str, 0, &parameter[parameter_size]);
                        if (ret) {
                                count = -EINVAL;