mirrors/linux-stable
1
0
Fork 0
mirror of https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git synced 2024-09-12 21:57:43 +00:00
Code Issues Releases Wiki Activity

mmc: core: fix regression: set default clock gating delay to 0

Browse source 
A recent commit "mmc: core: Use delayed work in clock gating framework"
(597dd9d79c) introduced a default 200ms delay before clock gating
actually takes place.  This means that every time an MMC interface
becomes idle it first stays on for 200ms before gating its clock. This
leads to increased power consumption and is therefore a clear regression.
This patch restores the original behaviour by setting the default delay
to 0. Users prioritising throughput over power efficiency can still
modify the delay via sysfs.

Signed-off-by: Guennadi Liakhovetski <g.liakhovetski@gmx.de>
Signed-off-by: Chris Ball <cjb@laptop.org>
This commit is contained in:
Guennadi Liakhovetski 2012-02-23 11:22:29 +01:00 committed by Chris Ball
parent 24e1511f67
commit c84f15aed2
1 changed files with 2 additions and 2 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

4
drivers/mmc/core/host.c
View file

@ -238,10 +238,10 @@ static inline void mmc_host_clk_init(struct mmc_host *host)
/* Hold MCI clock for 8 cycles by default */
host->clk_delay = 8;
/*
* Default clock gating delay is 200ms.
* Default clock gating delay is 0ms to avoid wasting power.
* This value can be tuned by writing into sysfs entry.
*/
host->clkgate_delay = 200;
host->clkgate_delay = 0;
host->clk_gated = false;
INIT_DELAYED_WORK(&host->clk_gate_work, mmc_host_clk_gate_work);
spin_lock_init(&host->clk_lock);