gpio: pca953x: Fix corruption of other gpios in set_multiple.

commit 53f8d322234649b4d6f1515b20c127a577efd164 upstream.

gpiod_set_array_value_complex does not clear the bits field.
Therefore when the drivers set_multiple funciton is called bits outside
the mask are undefined and can be either set or not. So bank_val needs
to be masked with bank_mask before or with the reg_val cache.

Fixes: b4818afeacbd ("gpio: pca953x: Add set_multiple to allow multiple")
Signed-off-by: Phil Reid <preid@electromag.com.au>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/gpio/gpio-pca953x.c b/drivers/gpio/gpio-pca953x.c
index 5fae629c241e6f012e86a81881fb56bcb23f46a8..47d08b9da60d1fedcef42b8a18f70b174d07824a 100644 (file)
--- a/drivers/gpio/gpio-pca953x.c
+++ b/drivers/gpio/gpio-pca953x.c
@@ -380,6 +380,7 @@ static void pca953x_gpio_set_multiple(struct gpio_chip *gc,
                if(bankmask) {
                        unsigned bankval  = bits[bank / sizeof(*bits)] >>
                                            ((bank % sizeof(*bits)) * 8);
+                       bankval &= bankmask;
                        reg_val[bank] = (reg_val[bank] & ~bankmask) | bankval;
                }
        }