[PATCH v7 1/1] PRUSS UIO driver support
Thomas Gleixner
tglx at linutronix.de
Tue Mar 1 16:45:25 EST 2011
On Wed, 2 Mar 2011, Pratheesh Gangadhar wrote:
> +
> +static DEFINE_SPINLOCK(lock);
> +static struct clk *pruss_clk;
> +static struct uio_info *info;
> +static dma_addr_t sram_paddr, ddr_paddr;
> +static void *prussio_vaddr, *sram_vaddr, *ddr_vaddr;
> +
> +static irqreturn_t pruss_handler(int irq, struct uio_info *info)
> +{
> + int intr_bit = (irq - IRQ_DA8XX_EVTOUT0 + 2);
> + int val, intr_mask = (1 << intr_bit);
> + void __iomem *base = info->mem[0].internal_addr;
> + void __iomem *intren_reg = base + PINTC_HIER;
> + void __iomem *intrstat_reg = base + PINTC_HIPIR + (intr_bit << 2);
> +
> + spin_lock_irq(&lock);
No, I said: spin_lock() is sufficient.
> + val = ioread32(intren_reg);
> + /* Is interrupt enabled and active ? */
> + if (!(val & intr_mask) && (ioread32(intrstat_reg) & HIPIR_NOPEND)) {
> + spin_unlock_irq(&lock);
You unconditinally enable interrupts here where you are not supposed
to do so.
> + return IRQ_NONE;
> + }
> +
> + /* Disable interrupt */
> + iowrite32((val & ~intr_mask), intren_reg);
> + spin_unlock_irq(&lock);
> + return IRQ_HANDLED;
> +}
> +
> +static int pruss_irqcontrol(struct uio_info *info, s32 irq_on)
> +{
> + int intr_bit = info->irq - IRQ_DA8XX_EVTOUT0 + 2;
> + int val, intr_mask = (1 << intr_bit);
> + void __iomem *base = info->mem[0].internal_addr;
> + void __iomem *intren_reg = base + PINTC_HIER;
> +
> + spin_lock_irq(&lock);
This one is correct, as this is always called from non interrupt
disabled context.
> + val = ioread32(intren_reg);
> + if (irq_on)
> + iowrite32((val | intr_mask), intren_reg);
> + else
> + iowrite32((val & ~intr_mask), intren_reg);
> + spin_unlock_irq(&lock);
> +
> + return 0;
> +}
> +
> + spin_lock_init(&lock);
Sigh. DEFINE_SPINLOCK(lock); already initializes the lock.
It's not the purpose of a review to tell you what you need to change
mechanically. Reviewers hint to a correct solution and you are
supposed to lookup what that solution means and act accordingly. If
you do not understand the hint or its implications please ask _before_
sending a new patch set.
Thanks,
tglx
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