mmc: tmio_mmc: Hotplug code regrouping
This patch regroups the code slightly, adds documentation and allows
the rtpm counter of MMC_CAP_NEEDS_POLL devices to reach 0 again.
Signed-off-by: Bastian Hecht <hechtb@gmail.com>
[g.liakhovetski@gmx.de: restore pm_runtime_get_noresume()]
Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
diff --git a/drivers/mmc/host/tmio_mmc_pio.c b/drivers/mmc/host/tmio_mmc_pio.c
index 4208b39..abad01b 100644
--- a/drivers/mmc/host/tmio_mmc_pio.c
+++ b/drivers/mmc/host/tmio_mmc_pio.c
@@ -800,8 +800,7 @@
} else if (ios->power_mode != MMC_POWER_UP) {
if (host->set_pwr && ios->power_mode == MMC_POWER_OFF)
host->set_pwr(host->pdev, 0);
- if ((pdata->flags & TMIO_MMC_HAS_COLD_CD) &&
- pdata->power) {
+ if (pdata->power) {
pdata->power = false;
pm_runtime_put(&host->pdev->dev);
}
@@ -915,6 +914,23 @@
if (ret < 0)
goto pm_disable;
+ /*
+ * There are 4 different scenarios for the card detection:
+ * 1) an external gpio irq handles the cd (best for power savings)
+ * 2) internal sdhi irq handles the cd
+ * 3) a worker thread polls the sdhi - indicated by MMC_CAP_NEEDS_POLL
+ * 4) the medium is non-removable - indicated by MMC_CAP_NONREMOVABLE
+ *
+ * While we increment the rtpm counter for all scenarios when the mmc
+ * core activates us by calling an appropriate set_ios(), we must
+ * additionally ensure that in case 2) the tmio mmc hardware stays
+ * powered on during runtime for the card detection to work.
+ */
+ if (!(pdata->flags & TMIO_MMC_HAS_COLD_CD
+ || mmc->caps & MMC_CAP_NEEDS_POLL
+ || mmc->caps & MMC_CAP_NONREMOVABLE))
+ pm_runtime_get_noresume(&pdev->dev);
+
tmio_mmc_clk_stop(_host);
tmio_mmc_reset(_host);
@@ -933,12 +949,6 @@
/* See if we also get DMA */
tmio_mmc_request_dma(_host, pdata);
- /* We have to keep the device powered for its card detection to work */
- if (!(pdata->flags & TMIO_MMC_HAS_COLD_CD)) {
- pdata->power = true;
- pm_runtime_get_noresume(&pdev->dev);
- }
-
mmc_add_host(mmc);
/* Unmask the IRQs we want to know about */
@@ -974,7 +984,9 @@
* the controller, the runtime PM is suspended and pdata->power == false,
* so, our .runtime_resume() will not try to detect a card in the slot.
*/
- if (host->pdata->flags & TMIO_MMC_HAS_COLD_CD)
+ if (host->pdata->flags & TMIO_MMC_HAS_COLD_CD
+ || host->mmc->caps & MMC_CAP_NEEDS_POLL
+ || host->mmc->caps & MMC_CAP_NONREMOVABLE)
pm_runtime_get_sync(&pdev->dev);
mmc_remove_host(host->mmc);