From: William Breathitt Gray wbg@kernel.org

[ Upstream commit 2ba5772e530f73eb847fb96ce6c4017894869552 ]

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: db02247827ef ("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 # ae495810cffe: 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... Signed-off-by: Bartosz Golaszewski bartosz.golaszewski@linaro.org [ Adjust context ] Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/gpio/gpio-idio-16.c | 5 +++++ 1 file changed, 5 insertions(+)

diff --git a/drivers/gpio/gpio-idio-16.c b/drivers/gpio/gpio-idio-16.c index 2c95125892972..f7e557c2c9cd4 100644 --- a/drivers/gpio/gpio-idio-16.c +++ b/drivers/gpio/gpio-idio-16.c @@ -3,6 +3,7 @@ * GPIO library for the ACCES IDIO-16 family * Copyright (C) 2022 William Breathitt Gray */ +#include <linux/bitmap.h> #include <linux/bits.h> #include <linux/device.h> #include <linux/err.h> @@ -106,6 +107,7 @@ 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; @@ -163,6 +165,9 @@ 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);

From: Vincent Mailhol mailhol.vincent@wanadoo.fr

[ Upstream commit 19408200c094858d952a90bf4977733dc89a4df5 ]

Add GENMASK_TYPE() which generalizes __GENMASK() to support different types, and implement fixed-types versions of GENMASK() based on it. The fixed-type version allows more strict checks to the min/max values accepted, which is useful for defining registers like implemented by i915 and xe drivers with their REG_GENMASK*() macros.

The strict checks rely on shift-count-overflow compiler check to fail the build if a number outside of the range allowed is passed. Example:

#define FOO_MASK GENMASK_U32(33, 4)

will generate a warning like:

include/linux/bits.h:51:27: error: right shift count >= width of type [-Werror=shift-count-overflow] 51 | type_max(t) >> (BITS_PER_TYPE(t) - 1 - (h))))) | ^~

The result is casted to the corresponding fixed width type. For example, GENMASK_U8() returns an u8. Note that because of the C promotion rules, GENMASK_U8() and GENMASK_U16() will immediately be promoted to int if used in an expression. Regardless, the main goal is not to get the correct type, but rather to enforce more checks at compile time.

While GENMASK_TYPE() is crafted to cover all variants, including the already existing GENMASK(), GENMASK_ULL() and GENMASK_U128(), for the moment, only use it for the newly introduced GENMASK_U*(). The consolidation will be done in a separate change.

Co-developed-by: Yury Norov yury.norov@gmail.com Signed-off-by: Lucas De Marchi lucas.demarchi@intel.com Acked-by: Jani Nikula jani.nikula@intel.com Signed-off-by: Vincent Mailhol mailhol.vincent@wanadoo.fr Reviewed-by: Andy Shevchenko andriy.shevchenko@linux.intel.com Signed-off-by: Yury Norov yury.norov@gmail.com Stable-dep-of: 2ba5772e530f ("gpio: idio-16: Define fixed direction of the GPIO lines") Signed-off-by: William Breathitt Gray wbg@kernel.org --- include/linux/bitops.h | 1 - include/linux/bits.h | 30 ++++++++++++++++++++++++++++++ 2 files changed, 30 insertions(+), 1 deletion(-)

diff --git a/include/linux/bitops.h b/include/linux/bitops.h index ba35bbf07798..65d084abbc2c 100644 --- a/include/linux/bitops.h +++ b/include/linux/bitops.h @@ -8,7 +8,6 @@

#include <uapi/linux/kernel.h>

-#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE) #define BITS_TO_LONGS(nr) __KERNEL_DIV_ROUND_UP(nr, BITS_PER_TYPE(long)) #define BITS_TO_U64(nr) __KERNEL_DIV_ROUND_UP(nr, BITS_PER_TYPE(u64)) #define BITS_TO_U32(nr) __KERNEL_DIV_ROUND_UP(nr, BITS_PER_TYPE(u32)) diff --git a/include/linux/bits.h b/include/linux/bits.h index 18143b536d9d..b48aa3209c2e 100644 --- a/include/linux/bits.h +++ b/include/linux/bits.h @@ -12,6 +12,7 @@ #define BIT_ULL_MASK(nr) (ULL(1) << ((nr) % BITS_PER_LONG_LONG)) #define BIT_ULL_WORD(nr) ((nr) / BITS_PER_LONG_LONG) #define BITS_PER_BYTE 8 +#define BITS_PER_TYPE(type) (sizeof(type) * BITS_PER_BYTE)

/* * Create a contiguous bitmask starting at bit position @l and ending at @@ -20,11 +21,40 @@ */ #if !defined(__ASSEMBLY__)

+/* + * Missing asm support + * + * GENMASK_U*() depend on BITS_PER_TYPE() which relies on sizeof(), + * something not available in asm. Nevertheless, fixed width integers is a C + * concept. Assembly code can rely on the long and long long versions instead. + */ + #include <linux/build_bug.h> +#include <linux/overflow.h> #define GENMASK_INPUT_CHECK(h, l) \ (BUILD_BUG_ON_ZERO(__builtin_choose_expr( \ __is_constexpr((l) > (h)), (l) > (h), 0)))

+/* + * Generate a mask for the specified type @t. Additional checks are made to + * guarantee the value returned fits in that type, relying on + * -Wshift-count-overflow compiler check to detect incompatible arguments. + * For example, all these create build errors or warnings: + * + * - GENMASK(15, 20): wrong argument order + * - GENMASK(72, 15): doesn't fit unsigned long + * - GENMASK_U32(33, 15): doesn't fit in a u32 + */ +#define GENMASK_TYPE(t, h, l) \ + ((t)(GENMASK_INPUT_CHECK(h, l) + \ + (type_max(t) << (l) & \ + type_max(t) >> (BITS_PER_TYPE(t) - 1 - (h))))) + +#define GENMASK_U8(h, l) GENMASK_TYPE(u8, h, l) +#define GENMASK_U16(h, l) GENMASK_TYPE(u16, h, l) +#define GENMASK_U32(h, l) GENMASK_TYPE(u32, h, l) +#define GENMASK_U64(h, l) GENMASK_TYPE(u64, h, l) + #else /* defined(__ASSEMBLY__) */

/*

From: Ioana Ciornei ioana.ciornei@nxp.com

[ Upstream commit 00aaae60faf554c27c95e93d47f200a93ff266ef ]

There are GPIO controllers such as the one present in the LX2160ARDB QIXIS FPGA which have fixed-direction input and output GPIO lines mixed together in a single register. This cannot be modeled using the gpio-regmap as-is since there is no way to present the true direction of a GPIO line.

In order to make this use case possible, add a new configuration parameter - fixed_direction_output - into the gpio_regmap_config structure. This will enable user drivers to provide a bitmap that represents the fixed direction of the GPIO lines.

Signed-off-by: Ioana Ciornei ioana.ciornei@nxp.com Acked-by: Bartosz Golaszewski bartosz.golaszewski@linaro.org Reviewed-by: Michael Walle mwalle@kernel.org Signed-off-by: Bartosz Golaszewski bartosz.golaszewski@linaro.org Stable-dep-of: 2ba5772e530f ("gpio: idio-16: Define fixed direction of the GPIO lines") Signed-off-by: William Breathitt Gray wbg@kernel.org --- drivers/gpio/gpio-regmap.c | 26 ++++++++++++++++++++++++-- include/linux/gpio/regmap.h | 5 +++++ 2 files changed, 29 insertions(+), 2 deletions(-)

diff --git a/drivers/gpio/gpio-regmap.c b/drivers/gpio/gpio-regmap.c index a9fd1398070e..fed9af5ff9ec 100644 --- a/drivers/gpio/gpio-regmap.c +++ b/drivers/gpio/gpio-regmap.c @@ -29,6 +29,7 @@ struct gpio_regmap { unsigned int reg_clr_base; unsigned int reg_dir_in_base; unsigned int reg_dir_out_base; + unsigned long *fixed_direction_output;

#ifdef CONFIG_REGMAP_IRQ int regmap_irq_line; @@ -122,6 +123,13 @@ static int gpio_regmap_get_direction(struct gpio_chip *chip, unsigned int base, val, reg, mask; int invert, ret;

+ if (gpio->fixed_direction_output) { + if (test_bit(offset, gpio->fixed_direction_output)) + return GPIO_LINE_DIRECTION_OUT; + else + return GPIO_LINE_DIRECTION_IN; + } + if (gpio->reg_dat_base && !gpio->reg_set_base) return GPIO_LINE_DIRECTION_IN; if (gpio->reg_set_base && !gpio->reg_dat_base) @@ -280,9 +288,20 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config chip->direction_output = gpio_regmap_direction_output; }

+ if (config->fixed_direction_output) { + gpio->fixed_direction_output = bitmap_alloc(chip->ngpio, + GFP_KERNEL); + if (!gpio->fixed_direction_output) { + ret = -ENOMEM; + goto err_free_gpio; + } + bitmap_copy(gpio->fixed_direction_output, + config->fixed_direction_output, chip->ngpio); + } + ret = gpiochip_add_data(chip, gpio); if (ret < 0) - goto err_free_gpio; + goto err_free_bitmap;

#ifdef CONFIG_REGMAP_IRQ if (config->regmap_irq_chip) { @@ -291,7 +310,7 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config config->regmap_irq_line, config->regmap_irq_flags, 0, config->regmap_irq_chip, &gpio->irq_chip_data); if (ret) - goto err_free_gpio; + goto err_free_bitmap;

irq_domain = regmap_irq_get_domain(gpio->irq_chip_data); } else @@ -308,6 +327,8 @@ struct gpio_regmap *gpio_regmap_register(const struct gpio_regmap_config *config

err_remove_gpiochip: gpiochip_remove(chip); +err_free_bitmap: + bitmap_free(gpio->fixed_direction_output); err_free_gpio: kfree(gpio); return ERR_PTR(ret); @@ -326,6 +347,7 @@ void gpio_regmap_unregister(struct gpio_regmap *gpio) #endif

gpiochip_remove(&gpio->gpio_chip); + bitmap_free(gpio->fixed_direction_output); kfree(gpio); } EXPORT_SYMBOL_GPL(gpio_regmap_unregister); diff --git a/include/linux/gpio/regmap.h b/include/linux/gpio/regmap.h index 76f6c73106dc..cf55202aaec2 100644 --- a/include/linux/gpio/regmap.h +++ b/include/linux/gpio/regmap.h @@ -37,6 +37,10 @@ struct regmap; * offset to a register/bitmask pair. If not * given the default gpio_regmap_simple_xlate() * is used. + * @fixed_direction_output: + * (Optional) Bitmap representing the fixed direction of + * the GPIO lines. Useful when there are GPIO lines with a + * fixed direction mixed together in the same register. * @drvdata: (Optional) Pointer to driver specific data which is * not used by gpio-remap but is provided "as is" to the * driver callback(s). @@ -82,6 +86,7 @@ struct gpio_regmap_config { int reg_stride; int ngpio_per_reg; struct irq_domain *irq_domain; + unsigned long *fixed_direction_output;

#ifdef CONFIG_REGMAP_IRQ struct regmap_irq_chip *regmap_irq_chip;