[v6,0/4] soc: samsung: usi: implement support for USIv1

Message

Ivaylo Ivanov Feb. 4, 2025, 5:27 p.m. UTC

Hey folks,

This patch series adds support for USIv1 in the existing exynos-usi driver,
as well as dedicated sysreg compatibles for exynos8895.

The USIv1 IP-core is found on some ARM64 Exynos SoCs (like Exynos8895).
It provides selectable serial protocols (one of: HSI2C0, HSI2C1, HSI2C0_1,
SPI, UART, UART_HSI2C1). It's a bit different from USIv2 as it doesn't
have any known MMIO register map and the serial protocols that it
implements share the same register base, hence why the way of modelling it
in device trees will be with ranges, like so:

usi1: usi@10460000 {
  compatible = "samsung,exynos8895-usi";
  ranges = <0x0 0x10460000 0x11000>;
  clocks = <1>, <2>;
  clock-names = "pclk", "ipclk";
  #address-cells = <1>;
  #size-cells = <1>;
  samsung,sysreg = <&syscon_peric0 0x1004>;
  status = "disabled";

  hsi2c_5: i2c@0 {
    compatible = "samsung,exynos8895-hsi2c";
    reg = <0x0 0x1000>;
    ...
  };
};

This patchset also assumes that [1] and [2] have been merged before it.
This has to be applied before the device tree changes [3].

Best regards,
Ivaylo

[1]: https://lore.kernel.org/all/[e-mail]/
[2]: https://lore.kernel.org/all/[e-mail]/
[3]: https://lore.kernel.org/all/[e-mail]/

Changes in v6:
  - move the action reset after usi init
  - make sure clocks are enabled during unconfiguring, otherwise return

Changes in v5:
  - add r-b tag from Krzysztof
  - make the usiv1 code a bit more symmetric
  - split the action reset into a different commmit

Changes in v4:
  - merge the first and second patch and don't break compilation
  - add exynos8895 compatible in the binding's oneOf:
  - keep exynos850's compatible in the first allOf: if
  - add exynos_usi_remove callback and error path at the end of probe,
    making sure to also have a removal routine for usiv2 and not just v1

Changes in v3:
  - drop the sysreg patch as it was applied
  - add a patch at the beginning of the series for renaming all USI_V2
    constants to USI_MODE_ and a patch at the end to rename them in dt
  - redo the usi binding support for 8895 to hopefully match all
    feedback from Krzysztof
  - change the description of the usiv1 and 8895 binding patch in order
    to account for the constants changes
  - change the subject and description of the usiv1 driver support patch
    because we're adding support for exynos8895 in the first place
  - make exynos_usi_modes a two dimensional array while also accounting
    for the merged usi mode constants

Changes in v2:
  - add r-b from Krzysztof Kozlowski <[e-mail]>
  - restrict the possible ids of samsung,mode with an allOf:if:then
  - set the properties samsung,clkreq-on and reg to false for non-usiv2
  - only make use of exynos_usi_modes
  - make sure pclk and ipclk are enabled

Ivaylo Ivanov (4):
  dt-bindings: soc: samsung: usi: add USIv1 and samsung,exynos8895-usi
  soc: samsung: usi: add a routine for unconfiguring the ip
  soc: samsung: usi: implement support for USIv1 and exynos8895
  arm64: dts: exynos: update all samsung,mode constants

 .../bindings/soc/samsung/exynos-usi.yaml      | 99 ++++++++++++-------
 arch/arm64/boot/dts/exynos/exynos850.dtsi     | 14 +--
 arch/arm64/boot/dts/exynos/exynosautov9.dtsi  | 48 ++++-----
 .../arm64/boot/dts/exynos/exynosautov920.dtsi |  2 +-
 .../boot/dts/exynos/google/gs101-oriole.dts   |  4 +-
 arch/arm64/boot/dts/exynos/google/gs101.dtsi  |  2 +-
 drivers/soc/samsung/exynos-usi.c              | 99 ++++++++++++++++---
 include/dt-bindings/soc/samsung,exynos-usi.h  | 17 +++-
 8 files changed, 200 insertions(+), 85 deletions(-)