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682696605c
For hosts not supporting MMC_CAP2_SDIO_IRQ_NOTHREAD but MMC_CAP_SDIO_IRQ, the SDIO IRQs are processed from a dedicated kernel thread. For these cases, the host calls mmc_signal_sdio_irq() from its ISR to signal a new SDIO IRQ. Signaling an SDIO IRQ makes the host's ->enable_sdio_irq() callback to be invoked to temporary disable the IRQs, before the kernel thread is woken up to process it. When processing of the IRQs are completed, they are re-enabled by the kernel thread, again via invoking the host's ->enable_sdio_irq(). The observation from this, is that the execution path is being unnecessary complex, as the host driver already knows that it needs to temporary disable the IRQs before signaling a new one. Moreover, replacing the kernel thread with a work/workqueue would not only greatly simplify the code, but also make it more robust. To address the above problems, let's continue to build upon the support for MMC_CAP2_SDIO_IRQ_NOTHREAD, as it already implements SDIO IRQs to be processed without using the clumsy kernel thread and without the ping-pong calls of the host's ->enable_sdio_irq() callback for each processed IRQ. Therefore, let's add new API sdio_signal_irq(), which enables hosts to signal/process SDIO IRQs by using a work/workqueue, rather than using the kernel thread. Add also a new host callback ->ack_sdio_irq(), which the work invokes when the SDIO IRQs have been processed. This informs the host about when it shall re-enable the SDIO IRQs. Potentially, we could re-use the existing ->enable_sdio_irq() callback instead of adding a new one, however it has turned out that it's more convenient for hosts to get this information via a separate callback. Hosts that wants to use this new method to signal/process SDIO IRQs, must enable MMC_CAP2_SDIO_IRQ_NOTHREAD and implement the ->ack_sdio_irq() callback. Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org> Tested-by: Douglas Anderson <dianders@chromium.org> Reviewed-by: Douglas Anderson <dianders@chromium.org> |
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block.c | ||
block.h | ||
bus.c | ||
bus.h | ||
card.h | ||
core.c | ||
core.h | ||
debugfs.c | ||
host.c | ||
host.h | ||
Kconfig | ||
Makefile | ||
mmc_ops.c | ||
mmc_ops.h | ||
mmc_test.c | ||
mmc.c | ||
pwrseq_emmc.c | ||
pwrseq_sd8787.c | ||
pwrseq_simple.c | ||
pwrseq.c | ||
pwrseq.h | ||
queue.c | ||
queue.h | ||
quirks.h | ||
sd_ops.c | ||
sd_ops.h | ||
sd.c | ||
sd.h | ||
sdio_bus.c | ||
sdio_bus.h | ||
sdio_cis.c | ||
sdio_cis.h | ||
sdio_io.c | ||
sdio_irq.c | ||
sdio_ops.c | ||
sdio_ops.h | ||
sdio_uart.c | ||
sdio.c | ||
slot-gpio.c | ||
slot-gpio.h |