Currently mmc host drivers have to decide, whether to enable card detection before calling mmc_add_host(), in which case a card insertion event can arrive before the host has been completely initialised, or after mmc_add_host(), in which case the initial card detection can be problematic. This patch adds an explicit indication, when card detection should not be carried out. With it in place enabling card detection before calling mmc_add_host() should be safe. Similarly, disabling it again after calling mmc_remove_host() will avoid any races.
Signed-off-by: Guennadi Liakhovetski <[email protected]> --- drivers/mmc/core/core.c | 2 ++ drivers/mmc/core/host.c | 2 ++ 2 files changed, 4 insertions(+), 0 deletions(-) diff --git a/drivers/mmc/core/core.c b/drivers/mmc/core/core.c index 4aa8658..385cadf 100644 --- a/drivers/mmc/core/core.c +++ b/drivers/mmc/core/core.c @@ -2099,6 +2099,7 @@ void mmc_rescan(struct work_struct *work) void mmc_start_host(struct mmc_host *host) { host->f_init = max(freqs[0], host->f_min); + host->rescan_disable = 0; mmc_power_up(host); mmc_detect_change(host, 0); } @@ -2112,6 +2113,7 @@ void mmc_stop_host(struct mmc_host *host) spin_unlock_irqrestore(&host->lock, flags); #endif + host->rescan_disable = 1; cancel_delayed_work_sync(&host->detect); mmc_flush_scheduled_work(); diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index 74cf29a5..597f189 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -313,6 +313,8 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev) if (!host) return NULL; + /* scanning will be enabled when we're ready */ + host->rescan_disable = 1; spin_lock(&mmc_host_lock); err = idr_get_new(&mmc_host_idr, host, &host->index); spin_unlock(&mmc_host_lock); -- 1.7.2.5 -- To unsubscribe from this list: send the line "unsubscribe linux-mmc" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
