Hi Masahiro,
On 22 December 2015 at 03:04, Masahiro Yamada
<yamada.masah...@socionext.com> wrote:
> Add device tree binding support for the clock uclass. This allows
> clock consumers to get the peripheral ID based on the "clocks"
> property in the device tree.
>
> Usage:
> Assume the following device tree:
>
> clk: myclock {
> compatible = "myclocktype";
> #clock-cells = <1>;
> };
>
> uart {
> compatible = "myuart";
> clocks = <&clk 3>;
> };
>
> i2c {
> compatible = "myi2c";
> clocks = <&clk 5>;
> };
>
> The UART, I2C driver can get the peripheral ID 3, 5, respectively
> by calling fdt_clk_get(). The clock provider should set its get_id
> callback to clk_get_id_simple. This should be enough for most cases
> although more complicated DT-PeripheralID translation would be
> possible by a specific get_id callback.
>
> Signed-off-by: Masahiro Yamada <yamada.masah...@socionext.com>
> ---
>
> drivers/clk/Makefile | 1 +
> drivers/clk/clk-fdt.c | 37 +++++++++++++++++++++++++++++++++++++
I think clk_fdt.c is better since we mostly avoid hyphens except for the uclass.
> include/clk.h | 20 ++++++++++++++++++++
> 3 files changed, 58 insertions(+)
> create mode 100644 drivers/clk/clk-fdt.c
>
> diff --git a/drivers/clk/Makefile b/drivers/clk/Makefile
> index 4a6a4a8..5fcdf39 100644
> --- a/drivers/clk/Makefile
> +++ b/drivers/clk/Makefile
> @@ -6,6 +6,7 @@
> #
>
> obj-$(CONFIG_CLK) += clk-uclass.o
> +obj-$(CONFIG_$(SPL_)OF_CONTROL) += clk-fdt.o
> obj-$(CONFIG_ROCKCHIP_RK3036) += clk_rk3036.o
> obj-$(CONFIG_ROCKCHIP_RK3288) += clk_rk3288.o
> obj-$(CONFIG_SANDBOX) += clk_sandbox.o
> diff --git a/drivers/clk/clk-fdt.c b/drivers/clk/clk-fdt.c
> new file mode 100644
> index 0000000..fc53157
> --- /dev/null
> +++ b/drivers/clk/clk-fdt.c
> @@ -0,0 +1,37 @@
> +/*
> + * Copyright (C) 2015 Masahiro Yamada <yamada.masah...@socionext.com>
> + *
> + * Device Tree support for clk uclass
> + *
> + * SPDX-License-Identifier: GPL-2.0+
> + */
> +
> +#include <clk.h>
> +#include <dm/uclass.h>
> +#include <fdtdec.h>
> +
> +int fdt_clk_get(const void *fdt, int nodeoffset, int index,
> + struct udevice **dev)
I think this should work using a device rather than a node offset.
I've pushed a working tree to u-boot-dm/rockchip-working to show what
I mean.
Also BTW I implemented your full pinctrl for rockchip in that tree -
seems to work well! The only problem is that init is quite slow. It
might be the phandle lookups, I'm not sure.
> +{
> + struct fdtdec_phandle_args clkspec;
> + struct udevice *clkdev;
> + int rc;
> +
> + rc = fdtdec_parse_phandle_with_args(fdt, nodeoffset, "clocks",
> + "#clock-cells", 0, index,
> &clkspec);
> + if (rc)
> + return rc;
> +
> + rc = uclass_get_device_by_of_offset(UCLASS_CLK, clkspec.node,
> &clkdev);
> + if (rc)
> + return rc;
> +
> + rc = clk_get_id(clkdev, clkspec.args_count, clkspec.args);
> + if (rc < 0)
> + return rc;
> +
> + if (dev)
> + *dev = clkdev;
> +
> + return rc;
> +}
> diff --git a/include/clk.h b/include/clk.h
> index 1efbaf2..518cb47 100644
> --- a/include/clk.h
> +++ b/include/clk.h
> @@ -121,4 +121,24 @@ static inline int clk_get_id_simple(struct udevice *dev,
> int args_count,
> return args_count > 0 ? args[0] : 0;
> }
>
> +#if CONFIG_IS_ENABLED(OF_CONTROL)
> +/**
> + * fdt_clk_get() - Get peripheral ID from device tree
> + *
> + * @fdt: FDT blob
> + * @periph: Offset of clock consumer node
> + * @index: index of a phandle to parse out in "clocks" property
> + * @dev: if not NULL, filled with pointer of clock provider
> + * @return peripheral ID, or -ve error code
> + */
> +int fdt_clk_get(const void *fdt, int nodeoffset, int index,
> + struct udevice **dev);
> +#else
> +static inline int fdt_clk_get(const void *fdt, int nodeoffset, int index,
> + struct udevice **dev);
> +{
> + return -ENOSYS;
> +}
> +#endif
> +
> #endif /* _CLK_H_ */
> --
> 1.9.1
>
Regards,
Simon
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