From: Eduardo Valentin Date: Thu, 20 Aug 2009 13:18:09 +0000 (+0300) Subject: OMAP: McBSP: Use appropriate value for startup delay X-Git-Tag: v3.12-rc1~11670^2~180 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=44a6311c0a83f682bcf18fae389a1b270df29314;p=kernel%2Fkernel-generic.git OMAP: McBSP: Use appropriate value for startup delay Increasing startup delay value as worst case: CLKSRG*2 = 8000khz: (1/8000) * 2 * 2 usec Although, 100us may give enough time for two CLKSRG, due to some unknown PM related, clock gating etc. reason, this patch increases it to 500us. Signed-off-by: Eduardo Valentin Acked-by: Tony Lindgren Signed-off-by: Mark Brown --- diff --git a/arch/arm/plat-omap/mcbsp.c b/arch/arm/plat-omap/mcbsp.c index 0aa2524..e9dd703 100644 --- a/arch/arm/plat-omap/mcbsp.c +++ b/arch/arm/plat-omap/mcbsp.c @@ -365,7 +365,13 @@ void omap_mcbsp_start(unsigned int id, int tx, int rx) w = OMAP_MCBSP_READ(io_base, SPCR1); OMAP_MCBSP_WRITE(io_base, SPCR1, w | (rx & 1)); - udelay(100); + /* + * Worst case: CLKSRG*2 = 8000khz: (1/8000) * 2 * 2 usec + * REVISIT: 100us may give enough time for two CLKSRG, however + * due to some unknown PM related, clock gating etc. reason it + * is now at 500us. + */ + udelay(500); if (idle) { /* Start frame sync */