Hi Jagan, On 10 October 2014 07:30, Jagan Teki <jagannadh.t...@gmail.com> wrote: > Hi Simon, > > On 10 October 2014 07:36, Simon Glass <s...@chromium.org> wrote: >> Hi Jagan, >> >> On 9 October 2014 04:33, Jagan Teki <jagannadh.t...@gmail.com> wrote: >>> On 9 October 2014 02:03, Simon Glass <s...@chromium.org> wrote: >>>> Hi, >>>> >>>> On 29 September 2014 13:34, Simon Glass <s...@chromium.org> wrote: >>>>> Up until now driver model has not been used for any type of bus. Buses >>>>> have some unique properties and needs, so we cannot claim that driver >>>>> model can cover all the common cases unless we have converted a bus over >>>>> to driver model. >>>>> >>>>> SPI is a reasonable choice for this next step. It has a fairly simple >>>>> API and not too many dependencies. The main one is SPI flash so we may >>>>> as well convert that also. Since the boards I test with have cros_ec I >>>>> have also included that, for SPI only. >>>>> >>>>> The technique used is make use of driver model's supported data structures >>>>> to hold information currently kept by each subsystem in a private data >>>>> structure. Since 'struct spi_slave' relates to the slave device on the bus >>>>> it is stored in the 'parent' data with each child device of the bus. >>>>> Since 'struct spi_flash' is a standard interface used for each SPI flash >>>>> driver, it is stored in the SPI FLash uclass's private data for each >>>>> device. >>>>> >>>>> New defines are created to enable driver model for each subsystem. These >>>>> are: >>>>> >>>>> CONFIG_DM_SPI >>>>> CONFIG_DM_SPI_FLASH >>>>> CONFIG_DM_CROS_EC >>>>> >>>>> This allows us to move some boards and drivers to driver model, while >>>>> leaving others behind. A 'big bang' conversion of everything to driver >>>>> model, even at a subsystem level, is never going to work. >>>>> >>>>> There is some cost in changing the uclass interface after it is created, >>>>> so if you have limited time, please spend it reviewing the uclass >>>>> interfaces in spi.h and spi_flash.h. These need to be supported by each >>>>> driver, so changing them later may involve changing multiple drivers. >>>>> >>>>> To assist with the conversion of other SPI drivers, a README file is >>>>> added to walk through the process. >>>>> >>>>> So far, sandbox, exynos and tegra drivers are converted over. >>>>> >>>>> As always, driver model patches are available at u-boot-dm.git branch >>>>> 'working'. There is a branch for just this series called 'spi-working'. >>>> >>>> I think this has had enough time out there. So I will push this to >>>> dm/next later this week. >>> >>> Sorry - I need to review a lot wrt v3. >>> I do understand that it has been in enough time, but this causes a >>> significant changes on >>> entire framework, please hold on for a while I need to think with >>> respect on qspi stuff with in >>> the spi framework. >> >> Well I'm not sure it supports setting of the flags that are needed for >> that. I don't have a platform to test with anyway. >> >> On the other hand adding that support to driver model could easily be >> a separate effort. I don't see a good reason to hold up the core SPI / >> SPI flash support. > > Partially agreed at this moment, let me think and review the whole stuff. > I would place all these stuff on to my master-next, once I'm OK. > > Any changes based on my strategy wrt qspi stuff - I may change these. > But I will push all these later on the 13/10 release. > > Comments?
Actually I'd like to bring this through the dm tree as I have a lot of dependent series that need to go that way. What is your timeline for further review of v3? I'm planning to push this to dm/next soon. I suggest adding the qspi stuff to sandbox. Then it will be easier to test with driver model. What do you think? Regards, Simon _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot
