Linux-ARM-Kernel Archive on lore.kernel.org
 help / color / mirror / Atom feed
From: Chanho Park <chanho61.park@samsung.com>
To: Tomasz Figa <tomasz.figa@gmail.com>,
	Krzysztof Kozlowski <krzk@kernel.org>,
	Sylwester Nawrocki <s.nawrocki@samsung.com>,
	Linus Walleij <linus.walleij@linaro.org>
Cc: Chanho Park <chanho61.park@samsung.com>,
	linux-samsung-soc@vger.kernel.org,
	linux-arm-kernel@lists.infradead.org
Subject: [PATCH] pinctrl: samsung: use raw_spinlock for locking
Date: Thu, 21 Jan 2021 12:00:09 +0900	[thread overview]
Message-ID: <20210121030009.25673-1-chanho61.park@samsung.com> (raw)
In-Reply-To: CGME20210121030006epcas2p40fd4e30ae5bf514b7891a464462db7be@epcas2p4.samsung.com

This patch converts spin_[lock|unlock] functions of pin bank to
raw_spinlock to support preempt-rt. This can avoid BUG() assertion when
irqchip callbacks are triggerred. Spinlocks can be converted rt_mutex
which is preemptible when we apply preempt-rt patches.

According to "Documentation/driver-api/gpio/driver.rst",

"Realtime considerations: a realtime compliant GPIO driver should not
use spinlock_t or any sleepable APIs (like PM runtime) as part of its
irqchip implementation.

- spinlock_t should be replaced with raw_spinlock_t.[1]
"

Cc: Tomasz Figa <tomasz.figa@gmail.com>
Cc: Krzysztof Kozlowski <krzk@kernel.org>
Cc: Sylwester Nawrocki <s.nawrocki@samsung.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Chanho Park <chanho61.park@samsung.com>
---
 drivers/pinctrl/samsung/pinctrl-exynos.c  | 16 ++++++++--------
 drivers/pinctrl/samsung/pinctrl-s3c24xx.c |  4 ++--
 drivers/pinctrl/samsung/pinctrl-samsung.c | 22 +++++++++++-----------
 drivers/pinctrl/samsung/pinctrl-samsung.h |  2 +-
 4 files changed, 22 insertions(+), 22 deletions(-)

diff --git a/drivers/pinctrl/samsung/pinctrl-exynos.c b/drivers/pinctrl/samsung/pinctrl-exynos.c
index b9ea09fabf84..0cd7f33cdf25 100644
--- a/drivers/pinctrl/samsung/pinctrl-exynos.c
+++ b/drivers/pinctrl/samsung/pinctrl-exynos.c
@@ -58,13 +58,13 @@ static void exynos_irq_mask(struct irq_data *irqd)
 	unsigned long mask;
 	unsigned long flags;
 
-	spin_lock_irqsave(&bank->slock, flags);
+	raw_spin_lock_irqsave(&bank->slock, flags);
 
 	mask = readl(bank->eint_base + reg_mask);
 	mask |= 1 << irqd->hwirq;
 	writel(mask, bank->eint_base + reg_mask);
 
-	spin_unlock_irqrestore(&bank->slock, flags);
+	raw_spin_unlock_irqrestore(&bank->slock, flags);
 }
 
 static void exynos_irq_ack(struct irq_data *irqd)
@@ -97,13 +97,13 @@ static void exynos_irq_unmask(struct irq_data *irqd)
 	if (irqd_get_trigger_type(irqd) & IRQ_TYPE_LEVEL_MASK)
 		exynos_irq_ack(irqd);
 
-	spin_lock_irqsave(&bank->slock, flags);
+	raw_spin_lock_irqsave(&bank->slock, flags);
 
 	mask = readl(bank->eint_base + reg_mask);
 	mask &= ~(1 << irqd->hwirq);
 	writel(mask, bank->eint_base + reg_mask);
 
-	spin_unlock_irqrestore(&bank->slock, flags);
+	raw_spin_unlock_irqrestore(&bank->slock, flags);
 }
 
 static int exynos_irq_set_type(struct irq_data *irqd, unsigned int type)
@@ -169,14 +169,14 @@ static int exynos_irq_request_resources(struct irq_data *irqd)
 	shift = irqd->hwirq * bank_type->fld_width[PINCFG_TYPE_FUNC];
 	mask = (1 << bank_type->fld_width[PINCFG_TYPE_FUNC]) - 1;
 
-	spin_lock_irqsave(&bank->slock, flags);
+	raw_spin_lock_irqsave(&bank->slock, flags);
 
 	con = readl(bank->pctl_base + reg_con);
 	con &= ~(mask << shift);
 	con |= EXYNOS_PIN_FUNC_EINT << shift;
 	writel(con, bank->pctl_base + reg_con);
 
-	spin_unlock_irqrestore(&bank->slock, flags);
+	raw_spin_unlock_irqrestore(&bank->slock, flags);
 
 	return 0;
 }
@@ -192,14 +192,14 @@ static void exynos_irq_release_resources(struct irq_data *irqd)
 	shift = irqd->hwirq * bank_type->fld_width[PINCFG_TYPE_FUNC];
 	mask = (1 << bank_type->fld_width[PINCFG_TYPE_FUNC]) - 1;
 
-	spin_lock_irqsave(&bank->slock, flags);
+	raw_spin_lock_irqsave(&bank->slock, flags);
 
 	con = readl(bank->pctl_base + reg_con);
 	con &= ~(mask << shift);
 	con |= EXYNOS_PIN_FUNC_INPUT << shift;
 	writel(con, bank->pctl_base + reg_con);
 
-	spin_unlock_irqrestore(&bank->slock, flags);
+	raw_spin_unlock_irqrestore(&bank->slock, flags);
 
 	gpiochip_unlock_as_irq(&bank->gpio_chip, irqd->hwirq);
 }
diff --git a/drivers/pinctrl/samsung/pinctrl-s3c24xx.c b/drivers/pinctrl/samsung/pinctrl-s3c24xx.c
index 2223ead5bd72..00d77d6946b5 100644
--- a/drivers/pinctrl/samsung/pinctrl-s3c24xx.c
+++ b/drivers/pinctrl/samsung/pinctrl-s3c24xx.c
@@ -145,14 +145,14 @@ static void s3c24xx_eint_set_function(struct samsung_pinctrl_drv_data *d,
 	shift = pin * bank_type->fld_width[PINCFG_TYPE_FUNC];
 	mask = (1 << bank_type->fld_width[PINCFG_TYPE_FUNC]) - 1;
 
-	spin_lock_irqsave(&bank->slock, flags);
+	raw_spin_lock_irqsave(&bank->slock, flags);
 
 	val = readl(reg);
 	val &= ~(mask << shift);
 	val |= bank->eint_func << shift;
 	writel(val, reg);
 
-	spin_unlock_irqrestore(&bank->slock, flags);
+	raw_spin_unlock_irqrestore(&bank->slock, flags);
 }
 
 static int s3c24xx_eint_type(struct irq_data *data, unsigned int type)
diff --git a/drivers/pinctrl/samsung/pinctrl-samsung.c b/drivers/pinctrl/samsung/pinctrl-samsung.c
index 608eb5a07248..376876bd6605 100644
--- a/drivers/pinctrl/samsung/pinctrl-samsung.c
+++ b/drivers/pinctrl/samsung/pinctrl-samsung.c
@@ -400,14 +400,14 @@ static void samsung_pinmux_setup(struct pinctrl_dev *pctldev, unsigned selector,
 		reg += 4;
 	}
 
-	spin_lock_irqsave(&bank->slock, flags);
+	raw_spin_lock_irqsave(&bank->slock, flags);
 
 	data = readl(reg + type->reg_offset[PINCFG_TYPE_FUNC]);
 	data &= ~(mask << shift);
 	data |= func->val << shift;
 	writel(data, reg + type->reg_offset[PINCFG_TYPE_FUNC]);
 
-	spin_unlock_irqrestore(&bank->slock, flags);
+	raw_spin_unlock_irqrestore(&bank->slock, flags);
 }
 
 /* enable a specified pinmux by writing to registers */
@@ -451,7 +451,7 @@ static int samsung_pinconf_rw(struct pinctrl_dev *pctldev, unsigned int pin,
 	width = type->fld_width[cfg_type];
 	cfg_reg = type->reg_offset[cfg_type];
 
-	spin_lock_irqsave(&bank->slock, flags);
+	raw_spin_lock_irqsave(&bank->slock, flags);
 
 	mask = (1 << width) - 1;
 	shift = pin_offset * width;
@@ -468,7 +468,7 @@ static int samsung_pinconf_rw(struct pinctrl_dev *pctldev, unsigned int pin,
 		*config = PINCFG_PACK(cfg_type, data);
 	}
 
-	spin_unlock_irqrestore(&bank->slock, flags);
+	raw_spin_unlock_irqrestore(&bank->slock, flags);
 
 	return 0;
 }
@@ -561,9 +561,9 @@ static void samsung_gpio_set(struct gpio_chip *gc, unsigned offset, int value)
 	struct samsung_pin_bank *bank = gpiochip_get_data(gc);
 	unsigned long flags;
 
-	spin_lock_irqsave(&bank->slock, flags);
+	raw_spin_lock_irqsave(&bank->slock, flags);
 	samsung_gpio_set_value(gc, offset, value);
-	spin_unlock_irqrestore(&bank->slock, flags);
+	raw_spin_unlock_irqrestore(&bank->slock, flags);
 }
 
 /* gpiolib gpio_get callback function */
@@ -626,9 +626,9 @@ static int samsung_gpio_direction_input(struct gpio_chip *gc, unsigned offset)
 	unsigned long flags;
 	int ret;
 
-	spin_lock_irqsave(&bank->slock, flags);
+	raw_spin_lock_irqsave(&bank->slock, flags);
 	ret = samsung_gpio_set_direction(gc, offset, true);
-	spin_unlock_irqrestore(&bank->slock, flags);
+	raw_spin_unlock_irqrestore(&bank->slock, flags);
 	return ret;
 }
 
@@ -640,10 +640,10 @@ static int samsung_gpio_direction_output(struct gpio_chip *gc, unsigned offset,
 	unsigned long flags;
 	int ret;
 
-	spin_lock_irqsave(&bank->slock, flags);
+	raw_spin_lock_irqsave(&bank->slock, flags);
 	samsung_gpio_set_value(gc, offset, value);
 	ret = samsung_gpio_set_direction(gc, offset, false);
-	spin_unlock_irqrestore(&bank->slock, flags);
+	raw_spin_unlock_irqrestore(&bank->slock, flags);
 
 	return ret;
 }
@@ -1057,7 +1057,7 @@ samsung_pinctrl_get_soc_data(struct samsung_pinctrl_drv_data *d,
 		bank->eint_offset = bdata->eint_offset;
 		bank->name = bdata->name;
 
-		spin_lock_init(&bank->slock);
+		raw_spin_lock_init(&bank->slock);
 		bank->drvdata = d;
 		bank->pin_base = d->nr_pins;
 		d->nr_pins += bank->nr_pins;
diff --git a/drivers/pinctrl/samsung/pinctrl-samsung.h b/drivers/pinctrl/samsung/pinctrl-samsung.h
index 379f34a9a482..de44f8ec330b 100644
--- a/drivers/pinctrl/samsung/pinctrl-samsung.h
+++ b/drivers/pinctrl/samsung/pinctrl-samsung.h
@@ -171,7 +171,7 @@ struct samsung_pin_bank {
 	struct gpio_chip gpio_chip;
 	struct pinctrl_gpio_range grange;
 	struct exynos_irq_chip *irq_chip;
-	spinlock_t slock;
+	raw_spinlock_t slock;
 
 	u32 pm_save[PINCFG_TYPE_NUM + 1]; /* +1 to handle double CON registers*/
 };
-- 
2.30.0


_______________________________________________
linux-arm-kernel mailing list
linux-arm-kernel@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/linux-arm-kernel

       reply	other threads:[~2021-01-21  3:02 UTC|newest]

Thread overview: 4+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <CGME20210121030006epcas2p40fd4e30ae5bf514b7891a464462db7be@epcas2p4.samsung.com>
2021-01-21  3:00 ` Chanho Park [this message]
2021-01-22 13:15   ` [PATCH] pinctrl: samsung: use raw_spinlock for locking Linus Walleij
2021-01-22 13:21     ` Krzysztof Kozlowski
2021-01-23 22:34   ` Linus Walleij

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=20210121030009.25673-1-chanho61.park@samsung.com \
    --to=chanho61.park@samsung.com \
    --cc=krzk@kernel.org \
    --cc=linus.walleij@linaro.org \
    --cc=linux-arm-kernel@lists.infradead.org \
    --cc=linux-samsung-soc@vger.kernel.org \
    --cc=s.nawrocki@samsung.com \
    --cc=tomasz.figa@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox