From e6e82a3087e6dad619149246082c910623ea9c36 Mon Sep 17 00:00:00 2001 From: Alexey Starikovskiy Date: Fri, 21 Mar 2008 17:06:57 +0300 Subject: [PATCH] ACPI: EC: Restore udelay in poll mode This fixes keyboard event handling on some systems. Note that this delay was thought unnecessary, and removed from linux-2.6.20 with 50c1e1138cb94f6aca0f8555777edbcefe0324e2 'ACPI: ec: Drop udelay() from poll mode. Loop by reading status field instead.' Signed-off-by: Alexey Starikovskiy Signed-off-by: Len Brown --- drivers/acpi/ec.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c index 7222a18..828c752 100644 --- a/drivers/acpi/ec.c +++ b/drivers/acpi/ec.c @@ -73,6 +73,7 @@ enum ec_event { #define ACPI_EC_DELAY 500 /* Wait 500ms max. during EC ops */ #define ACPI_EC_UDELAY_GLK 1000 /* Wait 1ms max. to get global lock */ +#define ACPI_EC_UDELAY 100 /* Wait 100us before polling EC again */ enum { EC_FLAGS_WAIT_GPE = 0, /* Don't check status until GPE arrives */ @@ -227,6 +228,7 @@ static int acpi_ec_wait(struct acpi_ec *ec, enum ec_event event, int force_poll) while (time_before(jiffies, delay)) { if (acpi_ec_check_status(ec, event)) goto end; + udelay(ACPI_EC_UDELAY); } } pr_err(PREFIX "acpi_ec_wait timeout," -- 2.7.4