ahci: Fix potential NULL ptr dereference.

This fixes coverity issue: 20360

Bug 200741055

Change-Id: I6bfdaf58b4d7d03a3c4edde6c229e9c1bc4164f7
Signed-off-by: Achal Verma <achalv@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvidia/+/2528439
Tested-by: Rahul Jain (SW-TEGRA) <rahuljain@nvidia.com>
Reviewed-by: Rahul Jain (SW-TEGRA) <rahuljain@nvidia.com>
Reviewed-on: https://git-master.nvidia.com/r/c/linux-nvidia/+/2575305
Tested-by: mobile promotions <svcmobile_promotions@nvidia.com>
Reviewed-by: svc-mobile-coverity <svc-mobile-coverity@nvidia.com>
Reviewed-by: Phoenix Jung <pjung@nvidia.com>
Reviewed-by: mobile promotions <svcmobile_promotions@nvidia.com>
GVS: Gerrit_Virtual_Submit

1 files changed, 16 insertions, 7 deletions

diff --git a/drivers/ata/tegra/ahci_tegra.c b/drivers/ata/tegra/ahci_tegra.c
index cd2602a59..9033e8324 100644
--- a/drivers/ata/tegra/ahci_tegra.c
+++ b/drivers/ata/tegra/ahci_tegra.c
@@ -1412,16 +1412,25 @@ static int tegra_ahci_disable_features(struct ahci_host_priv *hpriv)
 static int tegra_ahci_quirks(struct ahci_host_priv *hpriv)
 {
         struct tegra_ahci_priv *tegra = hpriv->plat_data;
-        struct platform_device *pdev = tegra->pdev;
-        struct device *dev = &pdev->dev;
-        u32 t_satao_nvoob_comma_cnt_mask =
-                        tegra->soc_data->reg.t_satao_nvoob_comma_cnt_mask;
-        u32 t_satao_nvoob_comma_cnt =
-                        tegra->soc_data->reg.t_satao_nvoob_comma_cnt;
+        struct platform_device *pdev;
+        struct device *dev;
+        u32 t_satao_nvoob_comma_cnt_mask;
+        u32 t_satao_nvoob_comma_cnt;
         unsigned int val;
         unsigned int mask;
         int ret = 0;
 
+        if (tegra) {
+                pdev = tegra->pdev;
+                dev = &pdev->dev;
+                t_satao_nvoob_comma_cnt_mask =
+                        tegra->soc_data->reg.t_satao_nvoob_comma_cnt_mask;
+                t_satao_nvoob_comma_cnt =
+                        tegra->soc_data->reg.t_satao_nvoob_comma_cnt;
+        } else {
+                return -ENODEV;
+        }
+
         /* SATA WARS */
         /* For SQUELCH Filter & Gen3 drive getting detected as Gen1 drive */
 
@@ -1443,7 +1452,7 @@ static int tegra_ahci_quirks(struct ahci_host_priv *hpriv)
         val = T_SATA0_CFG2NVOOB_2_COMWAKE_IDLE_CNT_LOW;
         tegra_ahci_scfg_update(hpriv, val, mask, T_SATA0_CFG2NVOOB_2);
 
-        if (tegra && tegra->prod_list) {
+        if (tegra->prod_list) {
                 tegra_ahci_scfg_writel(hpriv, T_SATA0_INDEX_CH1, T_SATA0_INDEX);
                 ret = tegra_prod_set_by_name(tegra->base_list, "prod",
                                                         tegra->prod_list);