[PATCH 11/11] pinctrl: stm32: add firewall checks before probing the HDP driver
From: Gatien Chevallier <gatien.chevallier@foss.st.com>
Date: 2026-01-09 10:59:04
Also in:
linux-devicetree, linux-gpio, lkml
Subsystem:
pin control subsystem, st stm32 hdp pinctrl driver, the rest · Maintainers:
Linus Walleij, Clément Le Goffic, Linus Torvalds
Because the HDP peripheral both depends on debug and firewall configuration, when CONFIG_STM32_FIREWALL is present, use the stm32 firewall framework to be able to check these configuration against the relevant controllers. Signed-off-by: Gatien Chevallier <gatien.chevallier@foss.st.com> --- drivers/pinctrl/stm32/pinctrl-stm32-hdp.c | 41 +++++++++++++++++++++++++++++++ 1 file changed, 41 insertions(+)
diff --git a/drivers/pinctrl/stm32/pinctrl-stm32-hdp.c b/drivers/pinctrl/stm32/pinctrl-stm32-hdp.c
index 0b1dff01e04c..7e4aa0465c06 100644
--- a/drivers/pinctrl/stm32/pinctrl-stm32-hdp.c
+++ b/drivers/pinctrl/stm32/pinctrl-stm32-hdp.c@@ -4,6 +4,7 @@ * Author: Clément Le Goffic <clement.legoffic@foss.st.com> for STMicroelectronics. */ #include <linux/bits.h> +#include <linux/bus/stm32_firewall_device.h> #include <linux/clk.h> #include <linux/gpio/driver.h> #include <linux/gpio/generic.h>
@@ -605,10 +606,50 @@ MODULE_DEVICE_TABLE(of, stm32_hdp_of_match); static int stm32_hdp_probe(struct platform_device *pdev) { struct gpio_generic_chip_config config; + struct stm32_firewall *firewall = NULL; struct device *dev = &pdev->dev; struct stm32_hdp *hdp; + int nb_firewall; u8 version; int err; + int i; + + nb_firewall = of_count_phandle_with_args(pdev->dev.of_node, "access-controllers", + "#access-controller-cells"); + if (IS_ENABLED(CONFIG_STM32_FIREWALL) && nb_firewall != -ENOENT) { + if (nb_firewall <= 0) + return -EINVAL; + + firewall = devm_kcalloc(dev, nb_firewall, sizeof(*firewall), GFP_KERNEL); + if (!firewall) + return -ENOMEM; + + /* Get stm32 firewall information */ + err = stm32_firewall_get_firewall(dev->of_node, firewall, nb_firewall); + if (err) + return dev_err_probe(dev, err, "Failed to get firewall controller\n"); + + for (i = 0; i < nb_firewall; i++) { + err = stm32_firewall_grant_access_by_id(firewall + i, + firewall[i].firewall_id); + if (err) { + while (i) { + u32 id; + + i--; + id = firewall[i].firewall_id; + stm32_firewall_release_access_by_id(firewall + i, id); + } + if (err == -EACCES) { + dev_info(dev, "No firewall access\n"); + return -ENODEV; + } + + return dev_err_probe(dev, err, "Error checking firewall access\n"); + } + } + } + hdp = devm_kzalloc(dev, sizeof(*hdp), GFP_KERNEL); if (!hdp)
--
2.43.0