Doug Anderson f8c58c1136 mmc: dw_mmc: Protect read-modify-write of INTMASK with a lock ... We're running into cases where our enabling of the SDIO interrupt in dw_mmc doesn't actually take effect. Specifically, adding patch like this: +++ b/drivers/mmc/host/dw_mmc.c @@ -1076,6 +1076,9 @@ static void dw_mci_enable_sdio_irq(struct mmc_host *mmc, int enb) mci_writel(host, INTMASK, (int_mask | SDMMC_INT_SDIO(slot->id))); + int_mask = mci_readl(host, INTMASK); + if (!(int_mask & SDMMC_INT_SDIO(slot->id))) + dev_err(&mmc->class_dev, "failed to enable sdio irq\n"); } else { ...actually triggers the error message. That's because the dw_mci_enable_sdio_irq() unsafely does a read-modify-write of the INTMASK register. We can't just use the standard host->lock since that lock is not irq safe and mmc_signal_sdio_irq() (called from interrupt context) calls dw_mci_enable_sdio_irq(). Add a new irq-safe lock to protect INTMASK. An alternate solution to this is to punt mmc_signal_sdio_irq() to the tasklet and then protect INTMASK modifications by the standard host lock. This seemed like a bit more of a high-latency change. Reported-by: Bing Zhao <bzhao@marvell.com> Signed-off-by: Doug Anderson <dianders@chromium.org> Reviewed-by: James Hogan <james.hogan@imgtec.com> Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>		2015-01-19 09:56:05 +01:00
..
card	mmc: queue: Improve error handling during allocation of bounce buffers	2014-12-05 10:33:17 +01:00
core	mmc: core: Support the optional init_card() callback for MMC and SD	2015-01-19 09:56:04 +01:00
host	mmc: dw_mmc: Protect read-modify-write of INTMASK with a lock	2015-01-19 09:56:05 +01:00
Kconfig	mmc: explicitly mention SDIO support in Kconfig	2008-10-12 11:04:36 +02:00
Makefile	mmc: sdhci-pci: add platform data	2012-01-11 23:58:47 -05:00