Messages in this thread | | | Subject | Re: [PATCH] Revert "spi: omap2-mcspi: Set FIFO DMA trigger level to word length" | From | David Lechner <> | Date | Mon, 14 Jan 2019 17:50:34 -0600 |
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On 1/14/19 6:30 AM, Vignesh R wrote: > > > On 14/01/19 2:19 AM, David Lechner wrote: >> This reverts commit b682cffa3ac6d9d9e16e9b413c45caee3b391fab. >> >> That commit breaks displays using tinydrm drivers, such as ili9225. >> >> It causes corruption in the image that is displayed (it looks like only >> 1/2 of the framebuffer data is sent, the other half of the display >> remains blank.) >> >> The following error appears multiple times: >> >> ili9225 spi1.0: EOW timed out >> >> Eventually, the system locks up without any additional errors. >> > > Oops, that's unfortunate. I see ili9225 is using bits_per_word = 16. > I believe commit b682cffa3ac6d9d broke spi_transfers where > bits_per_word anything other than 8 bits. > I don't have ili9225 HW but was able emulate this condition using a SPI > flash as slave on AM335x and successfully reproduced the issue. Could > you test if this diff[1] helps in fixing the regression without needing > to revert commit b682cffa3ac6d9d?
Yes, this changes fixes the problem. Thanks!
> > If below diff does not help, then could you post logs of types of > spi_transfers being queued by ili9225 driver? I guess you can dump them > by enabling DEBUG option in tinydrm-helpers.c. > Also which TI SoC are you using? > I'm using BeagleBone Green, so AM335x as well.
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