drivers: Remove explicit invocations of mmiowb()
mmiowb() is now implied by spin_unlock() on architectures that require it, so there is no reason to call it from driver code. This patch was generated using coccinelle: @mmiowb@ @@ - mmiowb(); and invoked as: $ for d in drivers include/linux/qed sound; do \ spatch --include-headers --sp-file mmiowb.cocci --dir $d --in-place; done NOTE: mmiowb() has only ever guaranteed ordering in conjunction with spin_unlock(). However, pairing each mmiowb() removal in this patch with the corresponding call to spin_unlock() is not at all trivial, so there is a small chance that this change may regress any drivers incorrectly relying on mmiowb() to order MMIO writes between CPUs using lock-free synchronisation. If you've ended up bisecting to this commit, you can reintroduce the mmiowb() calls using wmb() instead, which should restore the old behaviour on all architectures other than some esoteric ia64 systems. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
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@@ -338,7 +338,6 @@ static void ssb_pcmcia_write8(struct ssb_device *dev, u16 offset, u8 value)
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err = select_core_and_segment(dev, &offset);
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if (likely(!err))
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writeb(value, bus->mmio + offset);
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mmiowb();
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spin_unlock_irqrestore(&bus->bar_lock, flags);
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}
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@@ -352,7 +351,6 @@ static void ssb_pcmcia_write16(struct ssb_device *dev, u16 offset, u16 value)
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err = select_core_and_segment(dev, &offset);
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if (likely(!err))
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writew(value, bus->mmio + offset);
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mmiowb();
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spin_unlock_irqrestore(&bus->bar_lock, flags);
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}
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@@ -368,7 +366,6 @@ static void ssb_pcmcia_write32(struct ssb_device *dev, u16 offset, u32 value)
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writew((value & 0x0000FFFF), bus->mmio + offset);
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writew(((value & 0xFFFF0000) >> 16), bus->mmio + offset + 2);
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}
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mmiowb();
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spin_unlock_irqrestore(&bus->bar_lock, flags);
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}
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@@ -424,7 +421,6 @@ static void ssb_pcmcia_block_write(struct ssb_device *dev, const void *buffer,
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WARN_ON(1);
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}
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unlock:
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mmiowb();
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spin_unlock_irqrestore(&bus->bar_lock, flags);
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}
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#endif /* CONFIG_SSB_BLOCKIO */
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