"Karicheri, Muralidharan" <[email protected]> writes: > We had figured that was the issue with the clock being disabled. > > I see vpss master, vpss slave and vpss dac clocks defined. Now vpss > clock is required for all the vpss modules (capture, display, h3a > etc). In VPSS we have registers for enabling clocks for each module, > but the above clock is applicable for more than one driver. How does > driver request clock in this case?
Each driver that uses the clock should do a clk_get() and clk_enable(). The clock framework will track the usecounts and disable the hw clock when the usecount goes to zero, then re-enable the clock on the next clk_enable(). > I believe this should be enabled from the evm board setup. Right now > I have set the flag to ALWAYS_ENABLED. Hope this is fine. No. You enable the clock by calling clk_get()/clk_enable(). Kevin > Murali Karicheri > Software Design Engineer > Texas Instruments Inc. > Germantown, MD 20874 > Phone : 301-515-3736 > email: [email protected] > >>-----Original Message----- >>From: Kevin Hilman [mailto:[email protected]] >>Sent: Wednesday, May 13, 2009 5:35 PM >>To: Karicheri, Muralidharan >>Cc: [email protected] >>Subject: Re: DM355 - No vpss register write happens in the latest kernel >> >>"Karicheri, Muralidharan" <[email protected]> writes: >> >> >>> I have ported the video driver to the latest davinci git kernel and >>> I have built a single uImage for DM355 and DM6446. The driver works >>> fine on DM6446, but doesn't work on DM355. When I dumped the >>> registers, none of them were being written. I tried writing manually >>> using writel application and still I can't see the values in the >>> registers. The architecture code has changed recently quite a lot. I >>> have a version of the kernel that downloaded in March and this issue >>> was not seen there. This is blocking my driver work and any help >>> will be appreciated. >> >>My first guess would be that your driver doesn't enable all the >>relevant clocks for VPSS? >> >>You could try without the CONFIG_DAVINCI_RESET_CLOCKS=y in >>the config. >> >>If it works with that option disabled, then your driver has a bug in >>that it is not properly requesting clocks. >> >>Kevin >> _______________________________________________ Davinci-linux-open-source mailing list [email protected] http://linux.davincidsp.com/mailman/listinfo/davinci-linux-open-source
