@@ -10,6 +10,7 @@
#include <linux/gpio/driver.h>
#include <linux/io.h>
#include <linux/module.h>
+#include <linux/mutex.h>
#include <linux/of_device.h>
#include <linux/pinctrl/pinconf-generic.h>
#include <linux/pinctrl/pinconf.h>
@@ -138,7 +139,8 @@ struct rzg2l_pinctrl {
struct gpio_chip gpio_chip;
struct pinctrl_gpio_range gpio_range;
- spinlock_t lock;
+ spinlock_t lock; /* lock read/write registers */
+ struct mutex mutex; /* serialize adding groups and functions */
};
static const unsigned int iolh_groupa_mA[] = { 2, 4, 8, 12 };
@@ -348,11 +350,13 @@ static int rzg2l_dt_subnode_to_map(struct pinctrl_dev *pctldev,
name = np->name;
}
+ mutex_lock(&pctrl->mutex);
+
/* Register a single pin group listing all the pins we read from DT */
gsel = pinctrl_generic_add_group(pctldev, name, pins, num_pinmux, NULL);
if (gsel < 0) {
ret = gsel;
- goto done;
+ goto unlock;
}
/*
@@ -366,6 +370,8 @@ static int rzg2l_dt_subnode_to_map(struct pinctrl_dev *pctldev,
goto remove_group;
}
+ mutex_unlock(&pctrl->mutex);
+
maps[idx].type = PIN_MAP_TYPE_MUX_GROUP;
maps[idx].data.mux.group = name;
maps[idx].data.mux.function = name;
@@ -377,6 +383,8 @@ static int rzg2l_dt_subnode_to_map(struct pinctrl_dev *pctldev,
remove_group:
pinctrl_generic_remove_group(pctldev, gsel);
+unlock:
+ mutex_unlock(&pctrl->mutex);
done:
*index = idx;
kfree(configs);
@@ -1266,6 +1274,7 @@ static int rzg2l_pinctrl_probe(struct platform_device *pdev)
}
spin_lock_init(&pctrl->lock);
+ mutex_init(&pctrl->mutex);
platform_set_drvdata(pdev, pctrl);
commit 661efa2284bbc2338da0424e219603f034072c74 upstream. Fix the below random NULL pointer crash during boot by serializing pinctrl group and function creation/remove calls in rzg2l_dt_subnode_to_map() with mutex lock. Crash log: pc : __pi_strcmp+0x20/0x140 lr : pinmux_func_name_to_selector+0x68/0xa4 Call trace: __pi_strcmp+0x20/0x140 pinmux_generic_add_function+0x34/0xcc rzg2l_dt_subnode_to_map+0x314/0x44c rzg2l_dt_node_to_map+0x164/0x194 pinctrl_dt_to_map+0x218/0x37c create_pinctrl+0x70/0x3d8 While at it, add comments for bitmap_lock and lock. Fixes: c4c4637eb57f ("pinctrl: renesas: Add RZ/G2L pin and gpio controller driver") Tested-by: Chris Paterson <Chris.Paterson2@renesas.com> Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be> Link: https://lore.kernel.org/r/20230815131558.33787-2-biju.das.jz@bp.renesas.com Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be> [biju: dropped comments arund bitmap lock as support is not yet added in 5.10 ] Signed-off-by: Biju Das <biju.das.jz@bp.renesas.com> --- drivers/pinctrl/renesas/pinctrl-rzg2l.c | 13 +++++++++++-- 1 file changed, 11 insertions(+), 2 deletions(-)