Re: [BUG] ls1046a: eDMA does not transfer data from I2C

2022-09-22 Thread Sean Anderson
an König ; >>> linaro-mm-...@lists.linaro.org; Shawn Guo ; Sumit >>> Semwal ; Joy Zou ; linux- >>> me...@vger.kernel.org >>> Subject: Re: [BUG] ls1046a: eDMA does not transfer data from I2C >>> >>> >>> >>> On 9/20/22 11:44 AM

Re: [BUG] ls1046a: eDMA does not transfer data from I2C

2022-09-20 Thread Sean Anderson
nux-arm-kernel >> ; Vinod Koul ; >> dmaeng...@vger.kernel.org; Leo Li ; Laurentiu Tudor >> >> Cc: Linux Kernel Mailing List ; dri- >> de...@lists.freedesktop.org; Christian König ; >> linaro-mm-...@lists.linaro.org; Shawn Guo ; Sumit >> Semwal ; Joy Zou ; linux- >

RE: [BUG] ls1046a: eDMA does not transfer data from I2C

2022-09-20 Thread Leo Li
> > > > Despite the DMA completing successfully, no data was copied into the > > buffer, leaving the original (now junk) contents. I probed the I2C bus > > with an oscilloscope, and I verified that the transfer did indeed occur. > > The timing between submission and completion seems reasonable for

RE: [BUG] ls1046a: eDMA does not transfer data from I2C

2022-09-20 Thread Leo Li
tiu Tudor > > Cc: Linux Kernel Mailing List ; dri- > de...@lists.freedesktop.org; Christian König ; > linaro-mm-...@lists.linaro.org; Shawn Guo ; Sumit > Semwal ; Joy Zou ; linux- > me...@vger.kernel.org > Subject: Re: [BUG] ls1046a: eDMA does not transfer data from I2C >

Re: [BUG] ls1046a: eDMA does not transfer data from I2C

2022-09-20 Thread Sean Anderson
On 9/20/22 11:44 AM, Sean Anderson wrote: > > > On 9/20/22 11:24 AM, Sean Anderson wrote: >> >> >> On 9/20/22 6:07 AM, Robin Murphy wrote: >>> On 2022-09-19 23:24, Sean Anderson wrote: Hi all, I discovered a bug in either imx_i2c or fsl-edma on the LS1046A where no data

Re: [BUG] ls1046a: eDMA does not transfer data from I2C

2022-09-20 Thread Sean Anderson
On 9/20/22 11:24 AM, Sean Anderson wrote: > > > On 9/20/22 6:07 AM, Robin Murphy wrote: >> On 2022-09-19 23:24, Sean Anderson wrote: >>> Hi all, >>> >>> I discovered a bug in either imx_i2c or fsl-edma on the LS1046A where no >>> data is read in i2c_imx_dma_read except for the last two bytes

Re: [BUG] ls1046a: eDMA does not transfer data from I2C

2022-09-20 Thread Sean Anderson
On 9/20/22 6:07 AM, Robin Murphy wrote: > On 2022-09-19 23:24, Sean Anderson wrote: >> Hi all, >> >> I discovered a bug in either imx_i2c or fsl-edma on the LS1046A where no >> data is read in i2c_imx_dma_read except for the last two bytes (which >> are not read using DMA). This is perhaps best

Re: [BUG] ls1046a: eDMA does not transfer data from I2C

2022-09-20 Thread Robin Murphy
On 2022-09-19 23:24, Sean Anderson wrote: Hi all, I discovered a bug in either imx_i2c or fsl-edma on the LS1046A where no data is read in i2c_imx_dma_read except for the last two bytes (which are not read using DMA). This is perhaps best illustrated with the following example: # hexdump -C

Re: [BUG] ls1046a: eDMA does not transfer data from I2C

2022-09-20 Thread Sean Anderson
>> dmaeng...@vger.kernel.org >> Cc: Sumit Semwal ; Christian König >> ; Linux Kernel Mailing List > ker...@vger.kernel.org>; linux-me...@vger.kernel.org; dri- >> de...@lists.freedesktop.org; linaro-mm-...@lists.linaro.org; Joy Zou >> ; Peng Ma ; Robin Gong >

[BUG] ls1046a: eDMA does not transfer data from I2C

2022-09-20 Thread Sean Anderson
Hi all, I discovered a bug in either imx_i2c or fsl-edma on the LS1046A where no data is read in i2c_imx_dma_read except for the last two bytes (which are not read using DMA). This is perhaps best illustrated with the following example: # hexdump -C /sys/bus/nvmem/devices/0-00540/nvmem [

RE: [BUG] ls1046a: eDMA does not transfer data from I2C

2022-09-19 Thread Leo Li
> ; Linux Kernel Mailing List ker...@vger.kernel.org>; linux-me...@vger.kernel.org; dri- > de...@lists.freedesktop.org; linaro-mm-...@lists.linaro.org; Joy Zou > ; Peng Ma ; Robin Gong > ; Shawn Guo ; Leo Li > > Subject: [BUG] ls1046a: eDMA does not transfer data from I2C &