From 08da834a24312157f512224691ad1fddd11c1073 Mon Sep 17 00:00:00 2001 From: Daniel Drake Date: Wed, 20 Jul 2011 17:39:22 +0100 Subject: [PATCH] mmc: enable runtime PM by default Now that we have improved the runtime power management powerup/powerdown code, we believe that MMC_CAP_POWER_OFF_CARD is no longer necessary: runtime PM should now work everywhere. The only hard evidence for introducing MMC_CAP_POWER_OFF_CARD was the Marvell sd8686 wifi chip, which was believed to require external gpio manipulation which wasn't supported by some boards. After further investigation it was realized (and confirmed by Marvell folks) that sd8686 requirements can be fulfilled by changing the reset sequence itself, even if no external gpio is manipulated. For further information, see the following thread: http://www.mail-archive.com/linux-mmc@vger.kernel.org/msg04289.html Enable this trivially for a release or two. If no problems are reported, we will follow up with a more extensive patch to remove this flag altogether. If problems are reported, we can look at whitelist/blacklist possibilities as before. Signed-off-by: Daniel Drake Acked-by: Ohad Ben-Cohen Signed-off-by: Chris Ball --- drivers/mmc/core/host.c | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/drivers/mmc/core/host.c b/drivers/mmc/core/host.c index 793d0a0dad8d..ca2e4f50f615 100644 --- a/drivers/mmc/core/host.c +++ b/drivers/mmc/core/host.c @@ -301,6 +301,17 @@ struct mmc_host *mmc_alloc_host(int extra, struct device *dev) host->max_blk_size = 512; host->max_blk_count = PAGE_CACHE_SIZE / 512; + /* + * Enable runtime power management by default. This flag was added due + * to runtime power management causing disruption for some users, but + * the power on/off code has been improved since then. + * + * We'll enable this flag by default as an experiment, and if no + * problems are reported, we will follow up later and remove the flag + * altogether. + */ + host->caps = MMC_CAP_POWER_OFF_CARD; + return host; free: