https://community.nxp.com/t5/i-MX-Processors/CMA-area-for-I2C-client-driver/m-p/1725273#M212768 <P>I want to allocate memory for a cam driver by function dma_alloc_contiguous() which is using CMA internally.</P><P>I declare the cma region for my cam driver in device tree in kernel's cmdline. (cma=a=64M cma_map=mycam=a). The drivers name is "mycam". But this is field isn't set in init_name in device struct neither.</P><P>The problem is dma_alloc_contiguous needs struct device's field cma which is NULL when the probe function of mycam is called. Do I have to set this field on my own?<BR /><BR />Im using i.MX8mp Kernel 5.10.35</P> Tue, 19 Sep 2023 07:08:46 GMT heinzhjb 2023-09-19T07:08:46Z https://community.nxp.com/t5/i-MX-Processors/CMA-area-for-I2C-client-driver/m-p/1725273#M212768 <P>I want to allocate memory for a cam driver by function dma_alloc_contiguous() which is using CMA internally.</P><P>I declare the cma region for my cam driver in device tree in kernel's cmdline. (cma=a=64M cma_map=mycam=a). The drivers name is "mycam". But this is field isn't set in init_name in device struct neither.</P><P>The problem is dma_alloc_contiguous needs struct device's field cma which is NULL when the probe function of mycam is called. Do I have to set this field on my own?<BR /><BR />Im using i.MX8mp Kernel 5.10.35</P> Tue, 19 Sep 2023 07:08:46 GMT https://community.nxp.com/t5/i-MX-Processors/CMA-area-for-I2C-client-driver/m-p/1725273#M212768 heinzhjb 2023-09-19T07:08:46Z https://community.nxp.com/t5/i-MX-Processors/CMA-area-for-I2C-client-driver/m-p/1725952#M212831 <P>Hi&nbsp;<a href="https://community.nxp.com/t5/user/viewprofilepage/user-id/181496">@heinzhjb</a>,</P> <P>I hope you are doing well.</P> <P>One can refer to the below documents to allocate and debug contiguous memory for the driver.</P> <P><A href="https://github.com/nxp-imx/linux-imx/blob/lf-6.1.y/Documentation/core-api/dma-api.rst" target="_self">/Documentation/core-api/dma-api.rst</A></P> <P><A href="https://github.com/nxp-imx/linux-imx/blob/lf-6.1.y/Documentation/core-api/dma-api-howto.rst" target="_self">/Documentation/core-api/dma-api-howto.rst</A></P> <P><A href="https://stackoverflow.com/questions/35556593/how-to-work-with-reserved-cma-memory" target="_self">How to work with reserved CMA memory?</A></P> <P>Thanks &amp; Regards,<BR />Dhruvit Vasavada</P> Wed, 20 Sep 2023 06:15:52 GMT https://community.nxp.com/t5/i-MX-Processors/CMA-area-for-I2C-client-driver/m-p/1725952#M212831 Dhruvit 2023-09-20T06:15:52Z