linux-gpio.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Julia Cartwright <julia@ni.com>
To: Linus Walleij <linus.walleij@linaro.org>,
	Alexandre Courbot <gnurou@gmail.com>
Cc: linux-kernel@vger.kernel.org,
	Thomas Gleixner <tglx@linutronix.de>,
	linux-gpio@vger.kernel.org
Subject: [PATCH 08/19] gpio: etraxfs: make use of raw_spinlock variants
Date: Thu, 9 Mar 2017 10:21:55 -0600	[thread overview]
Message-ID: <c4411b58e928a3c2cf0375342051a31d71190eb5.1489015238.git.julia@ni.com> (raw)
In-Reply-To: <cover.1489015238.git.julia@ni.com>

The etraxfs gpio driver currently implements an irq_chip for handling
interrupts; due to how irq_chip handling is done, it's necessary for the
irq_chip methods to be invoked from hardirq context, even on a a
real-time kernel.  Because the spinlock_t type becomes a "sleeping"
spinlock w/ RT kernels, it is not suitable to be used with irq_chips.

A quick audit of the operations under the lock reveal that they do only
minimal, bounded work, and are therefore safe to do under a raw spinlock.

Signed-off-by: Julia Cartwright <julia@ni.com>
---
 drivers/gpio/gpio-etraxfs.c | 24 ++++++++++++------------
 1 file changed, 12 insertions(+), 12 deletions(-)

diff --git a/drivers/gpio/gpio-etraxfs.c b/drivers/gpio/gpio-etraxfs.c
index a254d5b07b94..14c6aac26780 100644
--- a/drivers/gpio/gpio-etraxfs.c
+++ b/drivers/gpio/gpio-etraxfs.c
@@ -54,7 +54,7 @@
 struct etraxfs_gpio_info;
 
 struct etraxfs_gpio_block {
-	spinlock_t lock;
+	raw_spinlock_t lock;
 	u32 mask;
 	u32 cfg;
 	u32 pins;
@@ -233,10 +233,10 @@ static void etraxfs_gpio_irq_mask(struct irq_data *d)
 	struct etraxfs_gpio_block *block = chip->block;
 	unsigned int grpirq = etraxfs_gpio_to_group_irq(d->hwirq);
 
-	spin_lock(&block->lock);
+	raw_spin_lock(&block->lock);
 	block->mask &= ~BIT(grpirq);
 	writel(block->mask, block->regs + block->info->rw_intr_mask);
-	spin_unlock(&block->lock);
+	raw_spin_unlock(&block->lock);
 }
 
 static void etraxfs_gpio_irq_unmask(struct irq_data *d)
@@ -246,10 +246,10 @@ static void etraxfs_gpio_irq_unmask(struct irq_data *d)
 	struct etraxfs_gpio_block *block = chip->block;
 	unsigned int grpirq = etraxfs_gpio_to_group_irq(d->hwirq);
 
-	spin_lock(&block->lock);
+	raw_spin_lock(&block->lock);
 	block->mask |= BIT(grpirq);
 	writel(block->mask, block->regs + block->info->rw_intr_mask);
-	spin_unlock(&block->lock);
+	raw_spin_unlock(&block->lock);
 }
 
 static int etraxfs_gpio_irq_set_type(struct irq_data *d, u32 type)
@@ -280,11 +280,11 @@ static int etraxfs_gpio_irq_set_type(struct irq_data *d, u32 type)
 		return -EINVAL;
 	}
 
-	spin_lock(&block->lock);
+	raw_spin_lock(&block->lock);
 	block->cfg &= ~(0x7 << (grpirq * 3));
 	block->cfg |= (cfg << (grpirq * 3));
 	writel(block->cfg, block->regs + block->info->rw_intr_cfg);
-	spin_unlock(&block->lock);
+	raw_spin_unlock(&block->lock);
 
 	return 0;
 }
@@ -297,7 +297,7 @@ static int etraxfs_gpio_irq_request_resources(struct irq_data *d)
 	unsigned int grpirq = etraxfs_gpio_to_group_irq(d->hwirq);
 	int ret = -EBUSY;
 
-	spin_lock(&block->lock);
+	raw_spin_lock(&block->lock);
 	if (block->group[grpirq])
 		goto out;
 
@@ -316,7 +316,7 @@ static int etraxfs_gpio_irq_request_resources(struct irq_data *d)
 	}
 
 out:
-	spin_unlock(&block->lock);
+	raw_spin_unlock(&block->lock);
 	return ret;
 }
 
@@ -327,10 +327,10 @@ static void etraxfs_gpio_irq_release_resources(struct irq_data *d)
 	struct etraxfs_gpio_block *block = chip->block;
 	unsigned int grpirq = etraxfs_gpio_to_group_irq(d->hwirq);
 
-	spin_lock(&block->lock);
+	raw_spin_lock(&block->lock);
 	block->group[grpirq] = 0;
 	gpiochip_unlock_as_irq(&chip->gc, d->hwirq);
-	spin_unlock(&block->lock);
+	raw_spin_unlock(&block->lock);
 }
 
 static struct irq_chip etraxfs_gpio_irq_chip = {
@@ -391,7 +391,7 @@ static int etraxfs_gpio_probe(struct platform_device *pdev)
 	if (!block)
 		return -ENOMEM;
 
-	spin_lock_init(&block->lock);
+	raw_spin_lock_init(&block->lock);
 
 	block->regs = regs;
 	block->info = info;
-- 
2.11.1


  parent reply	other threads:[~2017-03-09 18:08 UTC|newest]

Thread overview: 30+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
     [not found] <cover.1489015238.git.julia@ni.com>
2017-03-09 16:21 ` [PATCH 02/19] gpio: altera: make use of raw_spinlock variants Julia Cartwright
2017-03-15  9:53   ` Linus Walleij
2017-03-09 16:21 ` [PATCH 05/19] gpio: 104-dio-48e: " Julia Cartwright
2017-03-09 18:35   ` William Breathitt Gray
2017-03-15  9:54   ` Linus Walleij
2017-03-09 16:21 ` [PATCH 06/19] gpio: ath79: " Julia Cartwright
2017-03-13 19:51   ` Alban
2017-03-15  9:59   ` Linus Walleij
2017-03-09 16:21 ` [PATCH 07/19] gpio: bcm-kona: " Julia Cartwright
2017-03-10 17:28   ` Ray Jui
2017-03-10 19:35     ` Julia Cartwright
2017-03-15  9:57     ` Linus Walleij
2017-03-15  9:56   ` Linus Walleij
2017-03-09 16:21 ` Julia Cartwright [this message]
2017-03-15 10:00   ` [PATCH 08/19] gpio: etraxfs: " Linus Walleij
2017-03-09 16:21 ` [PATCH 09/19] gpio: pl061: " Julia Cartwright
2017-03-15 10:01   ` Linus Walleij
2017-03-09 16:21 ` [PATCH 10/19] gpio: ws16c48: " Julia Cartwright
2017-03-09 18:36   ` William Breathitt Gray
2017-03-15 10:02   ` Linus Walleij
2017-03-09 16:21 ` [PATCH 11/19] gpio: zx: " Julia Cartwright
2017-03-15 10:03   ` Linus Walleij
2017-03-09 16:22 ` [PATCH 16/19] pinctrl: bcm: " Julia Cartwright
2017-03-15 10:11   ` Linus Walleij
2017-03-09 16:22 ` [PATCH 17/19] pinctrl: amd: " Julia Cartwright
2017-03-15 10:12   ` Linus Walleij
2017-03-09 16:22 ` [PATCH 18/19] pinctrl: sirf: atlas7: " Julia Cartwright
2017-03-15 10:13   ` Linus Walleij
2017-03-09 16:22 ` [PATCH 19/19] pinctrl: sunxi: " Julia Cartwright
2017-03-15 10:14   ` 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=c4411b58e928a3c2cf0375342051a31d71190eb5.1489015238.git.julia@ni.com \
    --to=julia@ni.com \
    --cc=gnurou@gmail.com \
    --cc=linus.walleij@linaro.org \
    --cc=linux-gpio@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=tglx@linutronix.de \
    /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;
as well as URLs for NNTP newsgroup(s).