On Fri, Sep 03, 2010 at 11:45:22AM -0400, Eric Millbrandt wrote: > Tighten up time timing around the gpio reset functionality. Add a 200ns > delay before remuxing the pins back to ac97 to comply with the ac97 spec. > This delay ensures that sync and sdata_out are held low while reset > transitions to high. > > Signed-off-by: Eric Millbrandt <emillbra...@dekaresearch.com> > --- > > Scope shots are availible upon request. > > arch/powerpc/platforms/52xx/mpc52xx_common.c | 5 ++++- > 1 files changed, 4 insertions(+), 1 deletions(-) > > diff --git a/arch/powerpc/platforms/52xx/mpc52xx_common.c > b/arch/powerpc/platforms/52xx/mpc52xx_common.c > index 6e90531..79adfe7 100644 > --- a/arch/powerpc/platforms/52xx/mpc52xx_common.c > +++ b/arch/powerpc/platforms/52xx/mpc52xx_common.c > @@ -326,11 +326,14 @@ int mpc5200_psc_ac97_gpio_reset(int psc_number) > clrbits8(&wkup_gpio->wkup_dvo, reset); > > /* wait at lease 1 us */
Maybe you could fix this typo as well while you are here? > - udelay(2); > + udelay(1); > > /* Deassert reset */ > setbits8(&wkup_gpio->wkup_dvo, reset); > > + /* wait at least 200ns */ > + __delay(7); ndelay(200)? > + > /* Restore pin-muxing */ > out_be32(&simple_gpio->port_config, mux); > > -- > 1.6.3.1 > > -DISCLAIMER: an automatically appended disclaimer may follow. By posting- > -to a public e-mail mailing list I hereby grant permission to distribute- > -and copy this message.- > > This e-mail and the information, including any attachments, it contains are > intended to be a confidential communication only to the person or entity to > whom it is addressed and may contain information that is privileged. If the > reader of this message is not the intended recipient, you are hereby notified > that any dissemination, distribution or copying of this communication is > strictly prohibited. If you have received this communication in error, please > immediately notify the sender and destroy the original message. > > Thank you. > > Please consider the environment before printing this email. > _______________________________________________ > Linuxppc-dev mailing list > Linuxppc-dev@lists.ozlabs.org > https://lists.ozlabs.org/listinfo/linuxppc-dev -- Pengutronix e.K. | Wolfram Sang | Industrial Linux Solutions | http://www.pengutronix.de/ |
signature.asc
Description: Digital signature
_______________________________________________ Linuxppc-dev mailing list Linuxppc-dev@lists.ozlabs.org https://lists.ozlabs.org/listinfo/linuxppc-dev
