From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Boyd Subject: [PATCH v2 2/3] gpiolib-of: Support 'reserved-gpio-ranges' property Date: Thu, 25 Jan 2018 17:13:59 -0800 Message-ID: <20180126011400.2191-3-sboyd@codeaurora.org> References: <20180126011400.2191-1-sboyd@codeaurora.org> Return-path: In-Reply-To: <20180126011400.2191-1-sboyd-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Linus Walleij Cc: linux-kernel-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-msm-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org, Timur Tabi , Andy Shevchenko , Bjorn Andersson , linux-gpio-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Grant Likely , devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: devicetree@vger.kernel.org Some qcom platforms make some GPIOs or pins unavailable for use by non-secure operating systems, and thus reading or writing the registers for those pins will cause access control issues. Add support for a DT property to describe the set of GPIOs that are available for use so that higher level OSes are able to know what pins to avoid reading/writing. For now, we plumb this into the gpiochip irq APIs so that GPIO/pinctrl drivers can use the gpiochip_irqchip_irq_valid() to test validity of GPIOs. Signed-off-by: Stephen Boyd --- Or this can move into a dedicated API and not be tied to the irq code. Something like of_gpiochip_init_valid_mask? drivers/gpio/gpiolib-of.c | 28 ++++++++++++++++++++++++++++ drivers/gpio/gpiolib.c | 9 +++++++++ 2 files changed, 37 insertions(+) diff --git a/drivers/gpio/gpiolib-of.c b/drivers/gpio/gpiolib-of.c index 564bb7a31da4..194b3306ef74 100644 --- a/drivers/gpio/gpiolib-of.c +++ b/drivers/gpio/gpiolib-of.c @@ -498,6 +498,32 @@ void of_mm_gpiochip_remove(struct of_mm_gpio_chip *mm_gc) } EXPORT_SYMBOL(of_mm_gpiochip_remove); +#ifdef CONFIG_GPIOLIB_IRQCHIP +static void of_gpiochip_init_irq_valid_mask(struct gpio_chip *chip) +{ + int len, i; + u32 start, count; + struct device_node *np = chip->of_node; + + len = of_property_count_u32_elems(np, "reserved-gpio-ranges"); + if (len < 0 || len % 2 != 0) + return; + + for (i = 0; i < len; i += 2) { + of_property_read_u32_index(np, "reserved-gpio-ranges", + i, &start); + of_property_read_u32_index(np, "reserved-gpio-ranges", + i + 1, &count); + if (start >= chip->ngpio || start + count >= chip->ngpio) + continue; + + bitmap_clear(chip->irq.valid_mask, start, count); + } +}; +#else +static void of_gpiochip_init_irq_valid_mask(struct gpio_chip *chip) { } +#endif + #ifdef CONFIG_PINCTRL static int of_gpiochip_add_pin_range(struct gpio_chip *chip) { @@ -602,6 +628,8 @@ int of_gpiochip_add(struct gpio_chip *chip) if (chip->of_gpio_n_cells > MAX_PHANDLE_ARGS) return -EINVAL; + of_gpiochip_init_irq_valid_mask(chip); + status = of_gpiochip_add_pin_range(chip); if (status) return status; diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c index 930676ec9847..8483850463e6 100644 --- a/drivers/gpio/gpiolib.c +++ b/drivers/gpio/gpiolib.c @@ -1483,6 +1483,15 @@ static struct gpio_chip *find_chip_by_name(const char *name) static int gpiochip_irqchip_init_valid_mask(struct gpio_chip *gpiochip) { +#ifdef CONFIG_OF_GPIO + int size; + struct device_node *np = gpiochip->of_node; + + size = of_property_count_u32_elems(np, "reserved-gpio-ranges"); + if (size > 0 && size % 2 == 0) + gpiochip->irq.need_valid_mask = true; +#endif + if (!gpiochip->irq.need_valid_mask) return 0; -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html