This is a note to let you know that I've just added the patch titled pinctrl: microchip-sgpio: lock RMW access to the 5.15-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: pinctrl-microchip-sgpio-lock-rmw-access.patch and it can be found in the queue-5.15 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 322de47b04e550f9f49bd9fb4f403bc3daa0ce6f Author: Michael Walle <michael@xxxxxxxx> Date: Sat Feb 26 21:45:03 2022 +0100 pinctrl: microchip-sgpio: lock RMW access [ Upstream commit 7996c5f5ec7a20b3f6b8fae93fcf3cb8f1c01743 ] Protect any RMW access to the registers by a spinlock. Fixes: 7e5ea974e61c ("pinctrl: pinctrl-microchip-sgpio: Add pinctrl driver for Microsemi Serial GPIO") Signed-off-by: Michael Walle <michael@xxxxxxxx> Link: https://lore.kernel.org/r/20220226204507.2511633-2-michael@xxxxxxxx Signed-off-by: Linus Walleij <linus.walleij@xxxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/pinctrl/pinctrl-microchip-sgpio.c b/drivers/pinctrl/pinctrl-microchip-sgpio.c index 78765faa245a..dfa374195694 100644 --- a/drivers/pinctrl/pinctrl-microchip-sgpio.c +++ b/drivers/pinctrl/pinctrl-microchip-sgpio.c @@ -18,6 +18,7 @@ #include <linux/platform_device.h> #include <linux/property.h> #include <linux/reset.h> +#include <linux/spinlock.h> #include "core.h" #include "pinconf.h" @@ -115,6 +116,7 @@ struct sgpio_priv { u32 clock; u32 __iomem *regs; const struct sgpio_properties *properties; + spinlock_t lock; }; struct sgpio_port_addr { @@ -216,6 +218,7 @@ static void sgpio_output_set(struct sgpio_priv *priv, int value) { unsigned int bit = SGPIO_SRC_BITS * addr->bit; + unsigned long flags; u32 clr, set; switch (priv->properties->arch) { @@ -234,7 +237,10 @@ static void sgpio_output_set(struct sgpio_priv *priv, default: return; } + + spin_lock_irqsave(&priv->lock, flags); sgpio_clrsetbits(priv, REG_PORT_CONFIG, addr->port, clr, set); + spin_unlock_irqrestore(&priv->lock, flags); } static int sgpio_output_get(struct sgpio_priv *priv, @@ -562,10 +568,13 @@ static void microchip_sgpio_irq_settype(struct irq_data *data, struct sgpio_bank *bank = gpiochip_get_data(chip); unsigned int gpio = irqd_to_hwirq(data); struct sgpio_port_addr addr; + unsigned long flags; u32 ena; sgpio_pin_to_addr(bank->priv, gpio, &addr); + spin_lock_irqsave(&bank->priv->lock, flags); + /* Disable interrupt while changing type */ ena = sgpio_readl(bank->priv, REG_INT_ENABLE, addr.bit); sgpio_writel(bank->priv, ena & ~BIT(addr.port), REG_INT_ENABLE, addr.bit); @@ -582,6 +591,8 @@ static void microchip_sgpio_irq_settype(struct irq_data *data, /* Possibly re-enable interrupts */ sgpio_writel(bank->priv, ena, REG_INT_ENABLE, addr.bit); + + spin_unlock_irqrestore(&bank->priv->lock, flags); } static void microchip_sgpio_irq_setreg(struct irq_data *data, @@ -592,13 +603,16 @@ static void microchip_sgpio_irq_setreg(struct irq_data *data, struct sgpio_bank *bank = gpiochip_get_data(chip); unsigned int gpio = irqd_to_hwirq(data); struct sgpio_port_addr addr; + unsigned long flags; sgpio_pin_to_addr(bank->priv, gpio, &addr); + spin_lock_irqsave(&bank->priv->lock, flags); if (clear) sgpio_clrsetbits(bank->priv, reg, addr.bit, BIT(addr.port), 0); else sgpio_clrsetbits(bank->priv, reg, addr.bit, 0, BIT(addr.port)); + spin_unlock_irqrestore(&bank->priv->lock, flags); } static void microchip_sgpio_irq_mask(struct irq_data *data) @@ -814,6 +828,7 @@ static int microchip_sgpio_probe(struct platform_device *pdev) return -ENOMEM; priv->dev = dev; + spin_lock_init(&priv->lock); reset = devm_reset_control_get_optional_shared(&pdev->dev, "switch"); if (IS_ERR(reset))