gpio: idio-16: Define fixed direction of the GPIO lines

[ Upstream commit 2ba5772 ]

The direction of the IDIO-16 GPIO lines is fixed with the first 16 lines
as output and the remaining 16 lines as input. Set the gpio_config
fixed_direction_output member to represent the fixed direction of the
GPIO lines.

Fixes: db02247 ("gpio: idio-16: Migrate to the regmap API")
Reported-by: Mark Cave-Ayland <mark.caveayland@nutanix.com>
Closes: https://lore.kernel.org/r/9b0375fd-235f-4ee1-a7fa-daca296ef6bf@nutanix.com
Suggested-by: Michael Walle <mwalle@kernel.org>
Cc: stable@vger.kernel.org # ae49581: gpio: regmap: add the .fixed_direction_output configuration parameter
Cc: stable@vger.kernel.org
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: William Breathitt Gray <wbg@kernel.org>
Reviewed-by: Linus Walleij <linus.walleij@linaro.org>
Link: https://lore.kernel.org/r/20251020-fix-gpio-idio-16-regmap-v2-3-ebeb50e93c33@kernel.org
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@linaro.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

Author: William Breathitt Gray

drivers/gpio/gpio-idio-16.c

@@ -6,6 +6,7 @@
 
 #define DEFAULT_SYMBOL_NAMESPACE "GPIO_IDIO_16"
 
+#include <linux/bitmap.h>
 #include <linux/bits.h>
 #include <linux/device.h>
 #include <linux/err.h>
@@ -107,6 +108,7 @@ int devm_idio_16_regmap_register(struct device *const dev,
 	struct idio_16_data *data;
 	struct regmap_irq_chip *chip;
 	struct regmap_irq_chip_data *chip_data;
+	DECLARE_BITMAP(fixed_direction_output, IDIO_16_NGPIO);
 
 	if (!config->parent)
 		return -EINVAL;
@@ -164,6 +166,9 @@ int devm_idio_16_regmap_register(struct device *const dev,
 	gpio_config.irq_domain = regmap_irq_get_domain(chip_data);
 	gpio_config.reg_mask_xlate = idio_16_reg_mask_xlate;
 
+	bitmap_from_u64(fixed_direction_output, GENMASK_U64(15, 0));
+	gpio_config.fixed_direction_output = fixed_direction_output;
+
 	return PTR_ERR_OR_ZERO(devm_gpio_regmap_register(dev, &gpio_config));
 }
 EXPORT_SYMBOL_GPL(devm_idio_16_regmap_register);