From mboxrd@z Thu Jan 1 00:00:00 1970 From: Daniel Drake Date: Sun, 26 Sep 2010 14:57:23 +0000 Subject: Re: [PATCH 2/2] viafb: Add OLPC XO-1.5 port configs Message-Id: List-Id: References: <20100921153726.21D609D401B@zog.reactivated.net> In-Reply-To: <20100921153726.21D609D401B@zog.reactivated.net> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-fbdev@vger.kernel.org On 21 September 2010 18:54, Florian Tobias Schandinat wrote: > *after a deeper look at the patch* > Hm, one of my patches enables 0x26 also as I2C. So the only difference > between the current config and your config is whether 0x2c is GPIO or I2C > where your version make a lot more sense. > Jon, do you agree that this should become the default config? > Handling a GPIO device as such and not as an I2C device sounds right to me, > although we have to take care about the old code which is doing so. Jon, ping :) Something possibly of relevance: In addition to enabling the camera and DCON, changing the port config of 0x2c from VIA_MODE_I2C to VIA_MODE_GPIO makes a fairly substantial difference in the viafb init paths for XO-1.5. On linus master, before making the change in my patch, viafb init takes a long time, maybe 10 seconds. With linux-next 20100924, it takes 2.5 seconds. After the patch, it takes 0.07 seconds. Timings from linux-next: [ 1.021495] VIA Graphics Intergration Chipset framebuffer 2.4 initializing [ 1.029309] viafb 0000:00:01.0: PCI INT A -> GSI 16 (level, low) -> IRQ 16 [ 2.970023] viafb_init_dvi_size: DVI panel size undetected! [ 3.475728] Console: switching to colour frame buffer device 100x40 And from the same kernel with the port config adjusted: [ 1.025436] VIA Graphics Intergration Chipset framebuffer 2.4 initializing [ 1.033234] viafb 0000:00:01.0: PCI INT A -> GSI 16 (level, low) -> IRQ 16 [ 1.057799] viafb_init_dvi_size: DVI panel size undetected! [ 1.090548] Console: switching to colour frame buffer device 100x40 So, changing this value makes a pretty significant difference. If you changed it globally I'm wondering if you'd be breaking current non-XO systems, for example you'd be presumably affecting the behaviour of viafb_lvds_trasmitter_identify() At the same time, I don't fully understand what these port configs actually are, so I might be far off point. Daniel