The t7l66xb mfd 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 <[email protected]> --- drivers/mfd/t7l66xb.c | 20 ++++++++++---------- 1 file changed, 10 insertions(+), 10 deletions(-) diff --git a/drivers/mfd/t7l66xb.c b/drivers/mfd/t7l66xb.c index 94bd89cb1f06..22c811396edc 100644 --- a/drivers/mfd/t7l66xb.c +++ b/drivers/mfd/t7l66xb.c @@ -69,7 +69,7 @@ static const struct resource t7l66xb_mmc_resources[] = { struct t7l66xb { void __iomem *scr; /* Lock to protect registers requiring read/modify/write ops. */ - spinlock_t lock; + raw_spinlock_t lock; struct resource rscr; struct clk *clk48m; @@ -89,13 +89,13 @@ static int t7l66xb_mmc_enable(struct platform_device *mmc) clk_prepare_enable(t7l66xb->clk32k); - spin_lock_irqsave(&t7l66xb->lock, flags); + raw_spin_lock_irqsave(&t7l66xb->lock, flags); dev_ctl = tmio_ioread8(t7l66xb->scr + SCR_DEV_CTL); dev_ctl |= SCR_DEV_CTL_MMC; tmio_iowrite8(dev_ctl, t7l66xb->scr + SCR_DEV_CTL); - spin_unlock_irqrestore(&t7l66xb->lock, flags); + raw_spin_unlock_irqrestore(&t7l66xb->lock, flags); tmio_core_mmc_enable(t7l66xb->scr + 0x200, 0, t7l66xb_mmc_resources[0].start & 0xfffe); @@ -110,13 +110,13 @@ static int t7l66xb_mmc_disable(struct platform_device *mmc) unsigned long flags; u8 dev_ctl; - spin_lock_irqsave(&t7l66xb->lock, flags); + raw_spin_lock_irqsave(&t7l66xb->lock, flags); dev_ctl = tmio_ioread8(t7l66xb->scr + SCR_DEV_CTL); dev_ctl &= ~SCR_DEV_CTL_MMC; tmio_iowrite8(dev_ctl, t7l66xb->scr + SCR_DEV_CTL); - spin_unlock_irqrestore(&t7l66xb->lock, flags); + raw_spin_unlock_irqrestore(&t7l66xb->lock, flags); clk_disable_unprepare(t7l66xb->clk32k); @@ -206,11 +206,11 @@ static void t7l66xb_irq_mask(struct irq_data *data) unsigned long flags; u8 imr; - spin_lock_irqsave(&t7l66xb->lock, flags); + raw_spin_lock_irqsave(&t7l66xb->lock, flags); imr = tmio_ioread8(t7l66xb->scr + SCR_IMR); imr |= 1 << (data->irq - t7l66xb->irq_base); tmio_iowrite8(imr, t7l66xb->scr + SCR_IMR); - spin_unlock_irqrestore(&t7l66xb->lock, flags); + raw_spin_unlock_irqrestore(&t7l66xb->lock, flags); } static void t7l66xb_irq_unmask(struct irq_data *data) @@ -219,11 +219,11 @@ static void t7l66xb_irq_unmask(struct irq_data *data) unsigned long flags; u8 imr; - spin_lock_irqsave(&t7l66xb->lock, flags); + raw_spin_lock_irqsave(&t7l66xb->lock, flags); imr = tmio_ioread8(t7l66xb->scr + SCR_IMR); imr &= ~(1 << (data->irq - t7l66xb->irq_base)); tmio_iowrite8(imr, t7l66xb->scr + SCR_IMR); - spin_unlock_irqrestore(&t7l66xb->lock, flags); + raw_spin_unlock_irqrestore(&t7l66xb->lock, flags); } static struct irq_chip t7l66xb_chip = { @@ -321,7 +321,7 @@ static int t7l66xb_probe(struct platform_device *dev) if (!t7l66xb) return -ENOMEM; - spin_lock_init(&t7l66xb->lock); + raw_spin_lock_init(&t7l66xb->lock); platform_set_drvdata(dev, t7l66xb); -- 2.11.1
