[U-Boot] [PATCH V5 1/2] i2c: mxc: refactor i2c driver and support dm

[Simon Glass]

On 14 May 2015 at 17:29, Peng Fan <Peng.Fan at freescale.com> wrote:
> 1. Introduce a new structure `struct mxc_i2c_bus`, this structure will
>    used for non-DM and DM.
> 2. Remove `struct mxc_i2c_regs` structure, but use register offset to access
>    registers based on `base` entry of `struct mxc_i2c_bus`.
> 3. Remove most `#ifdef I2C_QUIRK_REG`. Using driver_data to contain platform
>    flags. A new flag is introduced, I2C_QUIRK_FLAG.
> 4. Most functions use `struct mxc_i2c_bus` as one of the parameters.
>    Make most functions common to DM and non-DM, try to avoid duplicated code.
> 5. Support DM, but pinctrl is not included. Pinmux setting is still set
>    by setup_i2c, but we do not need bus_i2c_init for DM.
> 6. struct i2c_parms and struct sram_data are removed.
> 7. Remove bus_i2c_read bus_i2c_write prototype in header file. The frist
>    paramter of bus_i2c_init is modified to i2c index. Add new prototype
>    i2c_idle_bus and force_bus_idle. Since bus_i2c_init is not good for
>    DM I2C and pinctrl is missed, we use a weak function for i2c_idle_bus.
>    Board file take the responsibility to implement this function, like this:
>    "
>    int i2c_idle_bus(struct mxc_i2c_bus *i2c_bus)
>    {
>            if (i2c_bus->index == 0)
>                    force_bus_idle(i2c_pads_info0);
>            else if (i2c_bus->index == 1)
>                    force_bus_idle(i2c_pads_info1);
>            else
>                    xxxxxx
>    }
>    "
> 8. Introduce a weak function, enable_i2c_clk
> 9. Tested on an i.MX7 platform. Log info:
>  => dm tree
>  Class       Probed   Name
>  ----------------------------------------
>  root        [ + ]    root_driver
>  simple_bus  [   ]    |-- soc
>  simple_bus  [   ]    |   |-- aips-bus at 30000000
>  simple_bus  [   ]    |   |   |-- anatop at 30360000
>  simple_bus  [   ]    |   |   `-- snvs at 30370000
>  simple_bus  [   ]    |   |-- aips-bus at 30400000
>  simple_bus  [   ]    |   `-- aips-bus at 30800000
>  i2c         [   ]    |       |-- i2c at 30a20000
>  i2c         [   ]    |       `-- i2c at 30a40000
>  simple_bus  [   ]    `-- regulators
>  => i2c dev 0
>  Setting bus to 0
>  => i2c probe
>  Valid chip addresses: 08 50
>  => i2c md 8 31
>  0031: 08 08 08 08 08 08 08 08 08 08 08 08 08 08 08 08
>
> Signed-off-by: Peng Fan <Peng.Fan at freescale.com>
> Acked-by: Simon Glass <sjg at chromium.org>
> ---
>
>  Changes v5:
>   none
>
>  Changes v4:
>  1. fix build errors
>  2. Introduce a weak function enable_i2c_clk.
>  3. add Simon's Acked-by.
>  4. Add test log in commit log.
>
>  Changes v3:
>   1. remove bus_i2c_init for DM, introuduce a weak function i2c_idle_bus.
>   2. remove static return type for force_idle_bus, since we need to call
>      it in i2c_idle_bus which may be implemented in board file. This does
>      not hurt for non-DM.
>
>  Changes v2:
>   1. Refactor driver, remove register access based on structure, but use
>     'base + offset'
>   2. Introduce mxc_i2c_bus structure
>   3. Introduce I2C_QUIRK_FLAG and remove most I2C_QUIRK_REG and use
>      driver_data to contain the flags for different platforms
>   4.  Avoid duplicated code between DM and non-DM part
>   5. The function name i2c_init_transfer is not changed.
>   6. Remove bus_i2c_read/write prototype from header file
>   7. change bus_i2c_init's first parameter to i2c index
>   8. Rename patch name, since refactor non-DM part.
>
>  arch/arm/imx-common/i2c-mxv7.c            |   7 +-
>  arch/arm/include/asm/imx-common/mxc_i2c.h |  38 +-
>  drivers/i2c/mxc_i2c.c                     | 581 ++++++++++++++++++++----------
>  3 files changed, 433 insertions(+), 193 deletions(-)

Applied to u-boot-dm, take 2, thanks!