This is a note to let you know that I've just added the patch titled gpio: tegra186: Fix tegra186_gpio_is_accessible() check to the 6.8-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: gpio-tegra186-fix-tegra186_gpio_is_accessible-check.patch and it can be found in the queue-6.8 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 011e41043e3fa96ce513a00e85069098b00ded7c Author: Prathamesh Shete <pshete@xxxxxxxxxx> Date: Wed Apr 24 15:25:14 2024 +0530 gpio: tegra186: Fix tegra186_gpio_is_accessible() check [ Upstream commit d806f474a9a7993648a2c70642ee129316d8deff ] The controller has several register bits describing access control information for a given GPIO pin. When SCR_SEC_[R|W]EN is unset, it means we have full read/write access to all the registers for given GPIO pin. When SCR_SEC[R|W]EN is set, it means we need to further check the accompanying SCR_SEC_G1[R|W] bit to determine read/write access to all the registers for given GPIO pin. This check was previously declaring that a GPIO pin was accessible only if either of the following conditions were met: - SCR_SEC_REN + SCR_SEC_WEN both set or - SCR_SEC_REN + SCR_SEC_WEN both set and SCR_SEC_G1R + SCR_SEC_G1W both set Update the check to properly handle cases where only one of SCR_SEC_REN or SCR_SEC_WEN is set. Fixes: b2b56a163230 ("gpio: tegra186: Check GPIO pin permission before access.") Signed-off-by: Prathamesh Shete <pshete@xxxxxxxxxx> Acked-by: Thierry Reding <treding@xxxxxxxxxx> Link: https://lore.kernel.org/r/20240424095514.24397-1-pshete@xxxxxxxxxx Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpio/gpio-tegra186.c b/drivers/gpio/gpio-tegra186.c index d87dd06db40d0..9130c691a2dd3 100644 --- a/drivers/gpio/gpio-tegra186.c +++ b/drivers/gpio/gpio-tegra186.c @@ -36,12 +36,6 @@ #define TEGRA186_GPIO_SCR_SEC_REN BIT(27) #define TEGRA186_GPIO_SCR_SEC_G1W BIT(9) #define TEGRA186_GPIO_SCR_SEC_G1R BIT(1) -#define TEGRA186_GPIO_FULL_ACCESS (TEGRA186_GPIO_SCR_SEC_WEN | \ - TEGRA186_GPIO_SCR_SEC_REN | \ - TEGRA186_GPIO_SCR_SEC_G1R | \ - TEGRA186_GPIO_SCR_SEC_G1W) -#define TEGRA186_GPIO_SCR_SEC_ENABLE (TEGRA186_GPIO_SCR_SEC_WEN | \ - TEGRA186_GPIO_SCR_SEC_REN) /* control registers */ #define TEGRA186_GPIO_ENABLE_CONFIG 0x00 @@ -177,10 +171,18 @@ static inline bool tegra186_gpio_is_accessible(struct tegra_gpio *gpio, unsigned value = __raw_readl(secure + TEGRA186_GPIO_SCR); - if ((value & TEGRA186_GPIO_SCR_SEC_ENABLE) == 0) - return true; + /* + * When SCR_SEC_[R|W]EN is unset, then we have full read/write access to all the + * registers for given GPIO pin. + * When SCR_SEC[R|W]EN is set, then there is need to further check the accompanying + * SCR_SEC_G1[R|W] bit to determine read/write access to all the registers for given + * GPIO pin. + */ - if ((value & TEGRA186_GPIO_FULL_ACCESS) == TEGRA186_GPIO_FULL_ACCESS) + if (((value & TEGRA186_GPIO_SCR_SEC_REN) == 0 || + ((value & TEGRA186_GPIO_SCR_SEC_REN) && (value & TEGRA186_GPIO_SCR_SEC_G1R))) && + ((value & TEGRA186_GPIO_SCR_SEC_WEN) == 0 || + ((value & TEGRA186_GPIO_SCR_SEC_WEN) && (value & TEGRA186_GPIO_SCR_SEC_G1W)))) return true; return false;