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>

1 files changed, 0 insertions, 10 deletions

diff --git a/drivers/mmc/host/via-sdmmc.c b/drivers/mmc/host/via-sdmmc.c
index 32c4211506fc..412395ac2935 100644
--- a/drivers/mmc/host/via-sdmmc.c
+++ b/drivers/mmc/host/via-sdmmc.c
@@ -686,7 +686,6 @@ static void via_sdc_request(struct mmc_host *mmc, struct mmc_request *mrq)
 		via_sdc_send_command(host, mrq->cmd);
 	}
 
-	mmiowb();
 	spin_unlock_irqrestore(&host->lock, flags);
 }
 
@@ -711,7 +710,6 @@ static void via_sdc_set_power(struct via_crdr_mmc_host *host,
 		gatt &= ~VIA_CRDR_PCICLKGATT_PAD_PWRON;
 	writeb(gatt, host->pcictrl_mmiobase + VIA_CRDR_PCICLKGATT);
 
-	mmiowb();
 	spin_unlock_irqrestore(&host->lock, flags);
 
 	via_pwron_sleep(host);
@@ -770,7 +768,6 @@ static void via_sdc_set_ios(struct mmc_host *mmc, struct mmc_ios *ios)
 	if (readb(addrbase + VIA_CRDR_PCISDCCLK) != clock)
 		writeb(clock, addrbase + VIA_CRDR_PCISDCCLK);
 
-	mmiowb();
 	spin_unlock_irqrestore(&host->lock, flags);
 
 	if (ios->power_mode != MMC_POWER_OFF)
@@ -830,7 +827,6 @@ static void via_reset_pcictrl(struct via_crdr_mmc_host *host)
 	via_restore_pcictrlreg(host);
 	via_restore_sdcreg(host);
 
-	mmiowb();
 	spin_unlock_irqrestore(&host->lock, flags);
 }
 
@@ -925,7 +921,6 @@ static irqreturn_t via_sdc_isr(int irq, void *dev_id)
 
 	result = IRQ_HANDLED;
 
-	mmiowb();
 out:
 	spin_unlock(&sdhost->lock);
 
@@ -960,7 +955,6 @@ static void via_sdc_timeout(struct timer_list *t)
 		}
 	}
 
-	mmiowb();
 	spin_unlock_irqrestore(&sdhost->lock, flags);
 }
 
@@ -1012,7 +1006,6 @@ static void via_sdc_card_detect(struct work_struct *work)
 			tasklet_schedule(&host->finish_tasklet);
 		}
 
-		mmiowb();
 		spin_unlock_irqrestore(&host->lock, flags);
 
 		via_reset_pcictrl(host);
@@ -1020,7 +1013,6 @@ static void via_sdc_card_detect(struct work_struct *work)
 		spin_lock_irqsave(&host->lock, flags);
 	}
 
-	mmiowb();
 	spin_unlock_irqrestore(&host->lock, flags);
 
 	via_print_pcictrl(host);
@@ -1188,7 +1180,6 @@ static void via_sd_remove(struct pci_dev *pcidev)
 
 	/* Disable generating further interrupts */
 	writeb(0x0, sdhost->pcictrl_mmiobase + VIA_CRDR_PCIINTCTRL);
-	mmiowb();
 
 	if (sdhost->mrq) {
 		pr_err("%s: Controller removed during "
@@ -1197,7 +1188,6 @@ static void via_sd_remove(struct pci_dev *pcidev)
 		/* make sure all DMA is stopped */
 		writel(VIA_CRDR_DMACTRL_SFTRST,
 			sdhost->ddma_mmiobase + VIA_CRDR_DMACTRL);
-		mmiowb();
 		sdhost->mrq->cmd->error = -ENOMEDIUM;
 		if (sdhost->mrq->stop)
 			sdhost->mrq->stop->error = -ENOMEDIUM;