regulator: lp8788-buck: Silence build warning

This driver use id as array index, thus add bounder checking for id.

This patch fixes below build warning:
drivers/regulator/lp8788-buck.c: In function 'lp8788_buck_probe':
drivers/regulator/lp8788-buck.c:490:8: warning: array subscript is above array bounds [-Warray-bounds]
drivers/regulator/lp8788-buck.c:489:63: warning: array subscript is above array bounds [-Warray-bounds]

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: Axel Lin <axel.lin@ingics.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

1 files changed, 4 insertions, 1 deletions

diff --git a/drivers/regulator/lp8788-buck.c b/drivers/regulator/lp8788-buck.c
index 11619493a5cb..ef845c7ac69f 100644
--- a/drivers/regulator/lp8788-buck.c
+++ b/drivers/regulator/lp8788-buck.c
@@ -474,7 +474,7 @@ static int lp8788_init_dvs(struct platform_device *pdev,
         u8 default_dvs_mode[] = { LP8788_BUCK1_DVS_I2C, LP8788_BUCK2_DVS_I2C };
 
         /* no dvs for buck3, 4 */
-        if (id == BUCK3 || id == BUCK4)
+        if (id > BUCK2)
                 return 0;
 
         /* no dvs platform data, then dvs will be selected by I2C registers */
@@ -505,6 +505,9 @@ static int lp8788_buck_probe(struct platform_device *pdev)
         struct regulator_dev *rdev;
         int ret;
 
+        if (id >= LP8788_NUM_BUCKS)
+                return -EINVAL;
+
         buck = devm_kzalloc(&pdev->dev, sizeof(struct lp8788_buck), GFP_KERNEL);
         if (!buck)
                 return -ENOMEM;