diff options
authorAndy Shevchenko <>2020-09-30 17:20:13 +0300
committerGreg Kroah-Hartman <>2020-10-07 08:02:53 +0200
commit7af706248ce2319292a634a94a18a0e380fc4975 (patch)
parentb7d42304148585a388d6516c87e1462282e7ebf6 (diff)
gpio: pca953x: Correctly initialize registers 6 and 7 for PCA957x
[ Upstream commit 8c1f1c34777bddb633d4a068a9c812d29974c6bd ] When driver has been converted to the bitmap API the non-bitmap functions started behaving differently on 32-bit BE architectures since the bytes in two consequent unsigned longs are in different order in comparison to byte array. Hence if the chip had had more than 32 lines the memset() call over it would have not set up upper lines correctly. Although it's currently a theoretical case (no supported chips of this type has 32+ lines), it's better to provide a clean code to avoid people thinking this is okay and potentially producing not fully working things. Fixes: 35d13d94893f ("gpio: pca953x: convert to use bitmap API") Signed-off-by: Andy Shevchenko <> Reviewed-by: Bartosz Golaszewski <> Link: Signed-off-by: Linus Walleij <> Signed-off-by: Sasha Levin <>
1 files changed, 4 insertions, 1 deletions
diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
index cc95f1630feb..11c3bbd105f1 100644
--- a/drivers/gpio/gpio-pca953x.c
+++ b/drivers/gpio/gpio-pca953x.c
@@ -938,6 +938,7 @@ out:
static int device_pca957x_init(struct pca953x_chip *chip, u32 invert)
+ unsigned int i;
int ret;
ret = device_pca95xx_init(chip, invert);
@@ -945,7 +946,9 @@ static int device_pca957x_init(struct pca953x_chip *chip, u32 invert)
goto out;
/* To enable register 6, 7 to control pull up and pull down */
- memset(val, 0x02, NBANK(chip));
+ for (i = 0; i < NBANK(chip); i++)
+ bitmap_set_value8(val, 0x02, i * BANK_SZ);
ret = pca953x_write_regs(chip, PCA957X_BKEN, val);
if (ret)
goto out;