Hi Jagan, On 30 June 2015 at 11:48, Jagan Teki <jt...@openedev.com> wrote: > Hi Simon, > > On 27 June 2015 at 04:32, Simon Glass <s...@chromium.org> wrote: >> Hi Jagan, >> >> On 26 June 2015 at 13:07, Jagan Teki <jt...@openedev.com> wrote: >>> Hi Simon, >>> >>> On 26 June 2015 at 21:23, Simon Glass <s...@chromium.org> wrote: >>>> Hi Jagan, >>>> >>>> On 23 June 2015 at 15:03, Jagan Teki <jt...@openedev.com> wrote: >>>>> Hi Simon, >>>>> >>>>> I'm calling spi_chip_select(bus) from set_speed or claim_bus >>>>> to get the cs value from sf probe. >>>>> >>>>> Seems like it returns the maximum number as 254, when I debug >>>>> further seems like slave_platdata returns NULL >>>>> >>>>> int spi_chip_select(struct udevice *dev) >>>>> { >>>>> struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev); >>>>> / * this plat data returns NULL */ >>>>> >>>>> return plat ? plat->cs : -ENOENT; >>>>> } >>>>> >>>> >>>> /** >>>> * spi_chip_select() - Get the chip select for a slave >>>> * >>>> * @return the chip select this slave is attached to >>>> */ >>>> int spi_chip_select(struct udevice *slave); >>>> >>>> This function takes a slave device as a parameter, not a bus. Are you >>>> passing it a bus? >>> >>> So as it's a struct udevice - I have passed it from probe and store my cs. >>> Seems like if you get the cs only if we call it from spi_xfer as it's slave >>> is it right? >> >> Both the bus and the slave device are devices, and thus use struct udevice. >> >> I really don't understand what you are asking/saying. Please can you >> try to be more descriptive? > > To finding out the cs number in spi driver, I'm trying to use spi_chip_select > from probe, but I couldn't find the valid cs number . > > I got the valid cs number only when I call spi_chip_select from xfer(), is > that > something like binding is properly done only when xfer() reaches?
To get the chip select, you can use: struct dm_spi_slave_platdata *plat = dev_get_parent_platdata(dev); plat->cs See the README also: 20. A little note about SPI uclass features: The SPI uclass keeps some information about each device 'dev' on the bus: struct dm_spi_slave_platdata - this is device_get_parent_platdata(dev) This is where the chip select number is stored, along with the default bus speed and mode. It is automatically read from the device tree in spi_child_post_bind(). It must not be changed at run-time after being set up because platform data is supposed to be immutable at run-time. struct spi_slave - this is device_get_parentdata(dev) Already mentioned above. It holds run-time information about the device. There are also some SPI uclass methods that get called behind the scenes: spi_post_bind() - called when a new bus is bound This scans the device tree for devices on the bus, and binds each one. This in turn causes spi_child_post_bind() to be called for each, which reads the device tree information into the parent (per-child) platform data. spi_child_post_bind() - called when a new child is bound As mentioned above this reads the device tree information into the per-child platform data spi_child_pre_probe() - called before a new child is probed This sets up the mode and speed in struct spi_slave by copying it from the parent's platform data for this child. It also sets the 'dev' pointer, needed to permit passing 'struct spi_slave' around the place without needing a separate 'struct udevice' pointer. The above housekeeping makes it easier to write your SPI driver. > >>>>> log: >>>>> zynq-uboot> sf probe 1:0 >>>>> zynq_spi_ofdata_to_platdata: regs=e0007000 max-frequency=166666700 >>>>> zynq_spi_set_speed: cs 254 >>>>> zynq_spi_set_speed: regs=e0007000, mode=1000000 >>>>> zynq_spi_set_mode: regs=e0007000, mode=3 >>>>> zynq_spi_claim_bus: cs 254 >>>>> spi_xfer: bus:1 cs:254 bitlen:8 len:1 flags:1 >>>>> spi_xfer: Timeout! TX FIFO not full >>>>> SF: Failed to get idcodes >>>>> Failed to initialize SPI flash at 1:0 (error -1) > > thanks! > -- > Jagan | openedev. Regards, Simon _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de http://lists.denx.de/mailman/listinfo/u-boot