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* [PATCH v22 0/4] Add ASPEED AST2600 I2C controller driver
@ 2025-11-12  8:56 Ryan Chen
  2025-11-12  8:56 ` [PATCH v22 1/4] dt-bindings: i2c: Split AST2600 binding into a new YAML Ryan Chen
                   ` (3 more replies)
  0 siblings, 4 replies; 6+ messages in thread
From: Ryan Chen @ 2025-11-12  8:56 UTC (permalink / raw)
  To: ryan_chen, bmc-sw, benh, joel, andi.shyti, jk, robh, krzk+dt,
	conor+dt, andrew, p.zabel, andriy.shevchenko, naresh.solanki,
	linux-i2c, openbmc, devicetree, linux-arm-kernel, linux-aspeed,
	linux-kernel

This series add AST2600 i2c new register set driver.
The i2c driver is new register set that have new clock divider option
for more flexiable generation. And also have separate i2c controller
and target register set for control, patch #2 is i2c controller driver
only, patch #3 is add i2c target mode driver.

The legacy register layout is mix controller/target register control
together. The following is add more detail description about new register
layout. And new feature set add for register.

v22:
- update patch (1/4) commit message add dts example reason.
- aspeed,ast2600-i2c.yaml @patch (1/4)
 - rename ast2600-i2c.yaml to aspeed,ast2600-i2c.yaml.
 - update reg, clock-frequency description.
- aspeed,ast2600-i2c.yaml @patch (2/4)
 - aspeed,transfer-mode, aspeed,transfer-mode add for ast2600.
- i2c-aspeed-core.c,h @patch (3/4)
 - add i2c-aspeed-core allow both old and new device trees using the
   same compatible string "aspeed,ast2600-i2c-bus".
 
v21:
- update patch (1/4) commit message
- i2c-ast2600.c
 - move rst to local variable in ast2600_i2c_probe().
 
v20:
- ast2600-i2c.yaml
 - fix warning at make dt_binding_check.

v19:
- Split AST2600 binding into its own YAML file
 - Removed `aspeed,ast2600-i2c-bus` from `aspeed,i2c.yaml`
 - Added `aspeed,global-regs` and `aspeed,transfer-mode` to AST2600 binding

v18:
- refine patch (1/3) commit message (reason for commit not list.)
- i2c-ast2600.c
 - remove redundant reset_control_deassert in driver probe.
 - remove reset_control_assert(i2c_bus->rst) in driver remove.

v17:
- move i2c new mode register and feature into driver commit message.
- aspeed,i2c.yaml
 - remove multi-master properties.
 - use aspeed,transfer-mode properties for aspeed,enable-byte/enable-dma.
-i2c-ast2600.c
 - rename dma_safe_buf to controller_dma_safe_buf.
 - fix ast2600_i2c_recover_bus return overflow warnings.
 - add ast2600_i2c_target_packet_buff_irq unhandle case.
 - add parameter "cmd" in ast2600_i2c_setup_dma_rx,
   ast2600_i2c_setup_buff_rx, ast2600_i2c_setup_byte_rx
 - use reset_control_deassert replace
   devm_reset_control_get_shared_deasserted.
 - useaspeed,transfer-mode properties for transfer mode setting.
 - change compatible = "aspeed,ast2600-i2cv2" to "aspeed,ast2600-i2c-bus".

v16:
- aspeed,i2c.yaml: add aspeed,enable-byte properties for force byte mode.
- i2c-ast2600.c
 - change include asm/unaligned.h to linux/unaligned.h.
 - add reset timeout councter when slave active timeout.
 - modify issue i2c_recovery_bus before slave re-enable.
 - add aspeed,enable-byte properties.

v15:
- i2c-ast2600.c
 - add include unaligned.h
 - rename all master -> controller, slave -> target.
 - keep multi-master to align property.
 - remove no used element in ast2600_i2c_bus.

v14:
- aspeed,i2c.yaml
 - v13 change people reviewed-by tag, v14 fixed to original people tag,
   modify to Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
 - struct ast2600_i2c_bus layout optimal.
 - ast2600_select_i2c_clock refine.
 - ast2600_i2c_recover_bus overridden fix.
 - dma_mapping_error() returned error code shadowed modify.
 - buffer register in a 4-byte aligned simplified
 - remove smbus alert

v13:
 - separate i2c master and slave driver to be two patchs.
 - modify include header list, add bits.h include. remove of*.h
 - modify (((x) >> 24) & GENMASK(5, 0)) to (((x) & GENMASK(29, 24)) >> 24)
 - modify ast2600_select_i2c_clock function implement.
 - modify ast2600_i2c_recover_bus function u32 claim to
   u32 state = readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);

v12:
- aspeed,i2c.yaml
 - add Reviewed-by: Krzysztof Kozlowski <krzysztof.kozlowski@linaro.org>
- i2c-ast2600.c
 - update include by alphabetical order
 - make just a one TAB and put the last two lines on the single one
 - remove no used timing_table structre
 - remove enum explicit assinment
 - rewritten to avoid this and using loop in ast2600_select_i2c_clock
 - use GENMASK for most 0xffff
 - remove too many parentheses
 - use str_read_write replace read write string
 - remove redundant blank line after ast2600_i2c_bus_of_table
 - fix wrong multi-line style of the comment
 - use macro for i2c standard speeds
 - remove useless noise dev_info

v11:
- aspeed,i2c.yaml
 - no change, the same with v10.
- i2c-ast2600.c
 - modify alert_enable from int -> boolean.
 - modify dbg string recovery -> recover.
 - remove no need to init 0.
 - remove new line after break.
 - remove unneeded empty line.
 - modify dma_alloc_coherent to dmam_alloc_coherent
 - modify probe nomem return dev_err_probe
 - modify i2c_add_adapter to devm_i2c_adapter
 - modify checkpatch: Alignment should match open parenthesis
 - modify checkpatch: braces {} should be used on all arms of this statement
 - modify checkpatch: Unbalanced braces around else statement

v10:
- aspeed,i2c.yaml
 - move unevaluatedProperties after allOf.
 - remove extra one blank line.
- i2c-ast2600.c
 - no change, the same with v8.

v9:
- aspeed,i2c.yaml
 - backoff to v7.
  - no fix typo in maintainer's name and email. this would be another patch.
  - no remove address-cells, size-cells, this would be another patch.
 - use aspeed,enable-dma property instead of aspeed,xfer-mode selection.
 - fix allOf and else false properties for aspeed,ast2600-i2cv2.
- i2c-ast2600.c
 - no change, the same with v8

v8:
- aspeed,i2c.yaml
 - modify commit message.
 - Fix typo in maintainer's name and email.
 - remove address-cells, size-cells.
- i2c-ast2600.c
 - move "i2c timeout counter" comment description before property_read.
 - remove redundant code "return ret" in probe end.

v7:
- aspeed,i2c.yaml
 - Update ASPEED I2C maintainers email.
 - use aspeed,enable-dma property instead of aspeed,xfer-mode selection.
 - fix allOf and else false properties for aspeed,ast2600-i2cv2.
- i2c-ast2600.c
 - remove aspeed,xfer-mode instead of aspeed,enable-dma mode. buffer mode
   is default.
 - remove aspeed,timeout instead of i2c-scl-clk-low-timeout-us for
   timeout setting.

v6:
- remove aspeed,i2cv2.yaml, merge to aspeed,i2c.yaml -add support for
  i2cv2 properites.
- i2c-ast2600.c
 - fix ast2600_i2c_remove ordering.
 - remove ast2600_i2c_probe goto labels, and add dev_err_probe -remove
   redundant deb_dbg debug message.
 - rename gr_regmap -> global_regs

v5:
- remove ast2600-i2c-global.yaml, i2c-ast2600-global.c.
- i2c-ast2600.c
 - remove legacy clock divide, all go for new clock divide.
 - remove duplicated read isr.
 - remove no used driver match
 - fix probe return for each labels return.
 - global use mfd driver, driver use phandle to regmap read/write.
- rename aspeed,i2c-ast2600.yaml to aspeed,i2cv2.yaml -remove bus-frequency.
- add required aspeed,gr
- add timeout, byte-mode, buff-mode properites.

v4:
- fix i2c-ast2600.c driver buffer mode use single buffer conflit in
  master slave mode both enable.
- fix kmemleak issue when use dma mode.
- fix typo aspeed,i2c-ast2600.yaml compatible is "aspeed,ast2600-i2c"
- fix typo aspeed,i2c-ast2600.ymal to aspeed,i2c-ast2600.yaml

v3:
- fix i2c global clock divide default value.
- remove i2c slave no used dev_dbg info.

v2:
- add i2c global ymal file commit.
- rename file name from new to ast2600.
  aspeed-i2c-new-global.c -> i2c-ast2600-global.c
  aspeed-i2c-new-global.h -> i2c-ast2600-global.h
  i2c-new-aspeed.c -> i2c-ast2600.c
- rename all driver function name to ast2600.

Ryan Chen (4):
  dt-bindings: i2c: Split AST2600 binding into a new YAML
  dt-bindings: i2c: ast2600-i2c.yaml: Add global-regs and transfer-mode
    properties
  i2c: ast2600: Add controller driver for new register layout
  i2c: ast2600: Add target mode support

 .../bindings/i2c/aspeed,ast2600-i2c.yaml      |   96 +
 .../devicetree/bindings/i2c/aspeed,i2c.yaml   |    3 +-
 drivers/i2c/busses/Makefile                   |    2 +-
 drivers/i2c/busses/i2c-aspeed-core.c          |   89 +
 drivers/i2c/busses/i2c-aspeed-core.h          |   19 +
 drivers/i2c/busses/i2c-aspeed.c               |   43 +-
 drivers/i2c/busses/i2c-ast2600.c              | 1578 +++++++++++++++++
 7 files changed, 1793 insertions(+), 37 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/i2c/aspeed,ast2600-i2c.yaml
 create mode 100644 drivers/i2c/busses/i2c-aspeed-core.c
 create mode 100644 drivers/i2c/busses/i2c-aspeed-core.h
 create mode 100644 drivers/i2c/busses/i2c-ast2600.c

-- 
2.34.1


^ permalink raw reply	[flat|nested] 6+ messages in thread

* [PATCH v22 1/4] dt-bindings: i2c: Split AST2600 binding into a new YAML
  2025-11-12  8:56 [PATCH v22 0/4] Add ASPEED AST2600 I2C controller driver Ryan Chen
@ 2025-11-12  8:56 ` Ryan Chen
  2025-11-13  8:00   ` Krzysztof Kozlowski
  2025-11-12  8:56 ` [PATCH v22 2/4] dt-bindings: i2c: ast2600-i2c.yaml: Add global-regs and transfer-mode properties Ryan Chen
                   ` (2 subsequent siblings)
  3 siblings, 1 reply; 6+ messages in thread
From: Ryan Chen @ 2025-11-12  8:56 UTC (permalink / raw)
  To: ryan_chen, bmc-sw, benh, joel, andi.shyti, jk, robh, krzk+dt,
	conor+dt, andrew, p.zabel, andriy.shevchenko, naresh.solanki,
	linux-i2c, openbmc, devicetree, linux-arm-kernel, linux-aspeed,
	linux-kernel

The AST2600 I2C controller introduces a completely new register
map and Separate control/target register sets, unlike the mixed
layout used in AST2400/AST2500.

In addition, at new AST2600 configuration registers and transfer
modes require new DT properties, which are incompatible with
existing bindings. Therefore, this creates a dedicated binding
file for AST2600 to properly describe these new hardware
capabilities.

A subsequent change will modify this new binding to properly
describe the AST2600 hardware.

The example section updated to reflect the actual AST2600 SoC
register layout and interrupt configuration.
Reference: aspeed-g6.dtsi (lines 885-897)

-I2C bus and buffeset address offsets
 - AST2600 I2C controller register base starts from 0x80, and the
   buffer region is located at 0xc00, as defined in AST2600 SOC
   register map.

-Interrupt configuration
 - AST2600 U2C controller are connected to ARM GIC interrupt
   controller rather than the legacy internal interrupt controller.

Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
---
 .../bindings/i2c/aspeed,ast2600-i2c.yaml      | 67 +++++++++++++++++++
 .../devicetree/bindings/i2c/aspeed,i2c.yaml   |  3 +-
 2 files changed, 68 insertions(+), 2 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/i2c/aspeed,ast2600-i2c.yaml

diff --git a/Documentation/devicetree/bindings/i2c/aspeed,ast2600-i2c.yaml b/Documentation/devicetree/bindings/i2c/aspeed,ast2600-i2c.yaml
new file mode 100644
index 000000000000..e6ed84c53639
--- /dev/null
+++ b/Documentation/devicetree/bindings/i2c/aspeed,ast2600-i2c.yaml
@@ -0,0 +1,67 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i2c/aspeed,ast2600-i2c.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: ASPEED I2C on the AST26XX SoCs
+
+maintainers:
+  - Ryan Chen <ryan_chen@aspeedtech.com>
+
+allOf:
+  - $ref: /schemas/i2c/i2c-controller.yaml#
+
+properties:
+  compatible:
+    enum:
+      - aspeed,ast2600-i2c-bus
+
+  reg:
+    minItems: 1
+    maxItems: 2
+    description:
+      The first region covers the controller registers.
+      The optional second region covers the controller's buffer space.
+
+  interrupts:
+    maxItems: 1
+
+  clocks:
+    maxItems: 1
+    description:
+      root clock of bus, should reference the APB
+      clock in the second cell
+
+  clock-frequency:
+    description: Desired operating frequency of the I2C bus in Hz.
+    minimum: 500
+    maximum: 4000000
+    default: 100000
+
+  resets:
+    maxItems: 1
+
+required:
+  - reg
+  - compatible
+  - clocks
+  - resets
+  - interrupts
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/aspeed-clock.h>
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    i2c@80 {
+      #address-cells = <1>;
+      #size-cells = <0>;
+      compatible = "aspeed,ast2600-i2c-bus";
+      reg = <0x80 0x80>, <0xc00 0x20>;
+      clocks = <&syscon ASPEED_CLK_APB>;
+      resets = <&syscon ASPEED_RESET_I2C>;
+      clock-frequency = <100000>;
+      interrupts = <GIC_SPI 110 IRQ_TYPE_LEVEL_HIGH>;
+    };
diff --git a/Documentation/devicetree/bindings/i2c/aspeed,i2c.yaml b/Documentation/devicetree/bindings/i2c/aspeed,i2c.yaml
index 5b9bd2feda3b..d4e4f412feba 100644
--- a/Documentation/devicetree/bindings/i2c/aspeed,i2c.yaml
+++ b/Documentation/devicetree/bindings/i2c/aspeed,i2c.yaml
@@ -4,7 +4,7 @@
 $id: http://devicetree.org/schemas/i2c/aspeed,i2c.yaml#
 $schema: http://devicetree.org/meta-schemas/core.yaml#
 
-title: ASPEED I2C on the AST24XX, AST25XX, and AST26XX SoCs
+title: ASPEED I2C on the AST24XX, AST25XX SoCs
 
 maintainers:
   - Rayn Chen <rayn_chen@aspeedtech.com>
@@ -17,7 +17,6 @@ properties:
     enum:
       - aspeed,ast2400-i2c-bus
       - aspeed,ast2500-i2c-bus
-      - aspeed,ast2600-i2c-bus
 
   reg:
     minItems: 1
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v22 2/4] dt-bindings: i2c: ast2600-i2c.yaml: Add global-regs and transfer-mode properties
  2025-11-12  8:56 [PATCH v22 0/4] Add ASPEED AST2600 I2C controller driver Ryan Chen
  2025-11-12  8:56 ` [PATCH v22 1/4] dt-bindings: i2c: Split AST2600 binding into a new YAML Ryan Chen
@ 2025-11-12  8:56 ` Ryan Chen
  2025-11-12  8:56 ` [PATCH v22 3/4] i2c: ast2600: Add controller driver for new register layout Ryan Chen
  2025-11-12  8:56 ` [PATCH v22 4/4] i2c: ast2600: Add target mode support Ryan Chen
  3 siblings, 0 replies; 6+ messages in thread
From: Ryan Chen @ 2025-11-12  8:56 UTC (permalink / raw)
  To: ryan_chen, bmc-sw, benh, joel, andi.shyti, jk, robh, krzk+dt,
	conor+dt, andrew, p.zabel, andriy.shevchenko, naresh.solanki,
	linux-i2c, openbmc, devicetree, linux-arm-kernel, linux-aspeed,
	linux-kernel

The AST2600 I2C controller supports three transfer modes: byte,
buffer, and DMA. To allow board designers and firmware to
explicitly select the preferred transfer mode for each controller
instance. "aspeed,transfer-mode" to allow device tree to specify
the desired transfer method used by each I2C controller instance.

And AST2600 i2c controller have two register mode, one is legacy
register layout which is mix controller/target register control
together, another is new mode which is separate controller/target
register control.

Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
---
 .../bindings/i2c/aspeed,ast2600-i2c.yaml      | 29 +++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/Documentation/devicetree/bindings/i2c/aspeed,ast2600-i2c.yaml b/Documentation/devicetree/bindings/i2c/aspeed,ast2600-i2c.yaml
index e6ed84c53639..89ae7cb2c772 100644
--- a/Documentation/devicetree/bindings/i2c/aspeed,ast2600-i2c.yaml
+++ b/Documentation/devicetree/bindings/i2c/aspeed,ast2600-i2c.yaml
@@ -42,6 +42,33 @@ properties:
   resets:
     maxItems: 1
 
+  aspeed,transfer-mode:
+    description: |
+      ASPEED ast2600 platform equipped with 16 I2C controllers each i2c controller
+      have 1 byte transfer buffer(byte mode), 32 bytes buffer(buffer mode), and
+      share a DMA engine.
+      Select I2C transfer mode for this controller. Supported values are:
+        - "byte": Use 1 byte for i2c transmit (1-byte buffer).
+        - "buffer": Use buffer (32-byte buffer) for i2c transmit. (default)
+                    Better performance then byte mode.
+        - "dma": Each controller DMA mode is shared DMA engine. The AST2600 SoC
+                 provides a single DMA engine shared for 16 I2C controllers,
+                 so only a limited number of controllers can use DMA simultaneously.
+                 Therefore, the DTS must explicitly assign which controllers are
+                 configured to use DMA.
+      On AST2600, each controller supports all three modes.
+      If not specified, buffer mode is used by default.
+    enum:
+      - byte
+      - buffer
+      - dma
+
+  aspeed,global-regs:
+    $ref: /schemas/types.yaml#/definitions/phandle
+    description:
+      Phandle reference to the i2c global syscon node, containing the
+      SoC-common i2c register set.
+
 required:
   - reg
   - compatible
@@ -64,4 +91,6 @@ examples:
       resets = <&syscon ASPEED_RESET_I2C>;
       clock-frequency = <100000>;
       interrupts = <GIC_SPI 110 IRQ_TYPE_LEVEL_HIGH>;
+      aspeed,global-regs = <&i2c_global>;
+      aspeed,transfer-mode = "buffer";
     };
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v22 3/4] i2c: ast2600: Add controller driver for new register layout
  2025-11-12  8:56 [PATCH v22 0/4] Add ASPEED AST2600 I2C controller driver Ryan Chen
  2025-11-12  8:56 ` [PATCH v22 1/4] dt-bindings: i2c: Split AST2600 binding into a new YAML Ryan Chen
  2025-11-12  8:56 ` [PATCH v22 2/4] dt-bindings: i2c: ast2600-i2c.yaml: Add global-regs and transfer-mode properties Ryan Chen
@ 2025-11-12  8:56 ` Ryan Chen
  2025-11-12  8:56 ` [PATCH v22 4/4] i2c: ast2600: Add target mode support Ryan Chen
  3 siblings, 0 replies; 6+ messages in thread
From: Ryan Chen @ 2025-11-12  8:56 UTC (permalink / raw)
  To: ryan_chen, bmc-sw, benh, joel, andi.shyti, jk, robh, krzk+dt,
	conor+dt, andrew, p.zabel, andriy.shevchenko, naresh.solanki,
	linux-i2c, openbmc, devicetree, linux-arm-kernel, linux-aspeed,
	linux-kernel

Add i2c-ast2600 new register mode driver to support AST2600
i2c new register mode. This i2c-ast2600 new driver and the
legacy i2c-aspeed driver both match the same compatible string
"aspeed,ast2600-i2c-bus" because they target the same I2C
controller IP on AST2600. However, AST2600 SoCs may configure
the controller instances to operate either in the legacy
register layout or the new layout (via global register).
The new register mode support following.

- Add new clock divider option for more flexible and accurate
 clock rate generation
- Add tCKHighMin timing to guarantee SCL high pulse width.
- Add support dual pool buffer mode, split 32 bytes pool buffer
 of each device into 2 x 16 bytes for Tx and Rx individually.
- Increase DMA buffer size to 4096 bytes and support byte alignment.
- Re-define the base address of BUS1 ~ BUS16 and Pool buffer.
- Re-define registers for separating controller and target
 mode control.
- Support 4 individual DMA buffers for controller Tx and Rx,
 target Tx and Rx.

And following is new register set for package transfer sequence.
- New Master operation mode:
  S -> Aw -> P
  S -> Aw -> TxD -> P
  S -> Ar -> RxD -> P
  S -> Aw -> TxD -> Sr -> Ar -> RxD -> P
- Bus SDA lock auto-release capability for new controller DMA
 command mode.
- Bus auto timeout for new controller/target DMA mode.

Since the register layout is selected via a global register at
runtime and both drivers bind to the same compatible string,
this patch defines the driver selection at build-time using
Kconfig, ensuring that only one driver is compiled into the
kernel. This approach avoids ambiguity and ensures consistent
behavior for each platform configuration.

The following is two versus register layout.
Old register mode:
{I2CD00}: Function Control Register
{I2CD04}: Clock and AC Timing Control Register
{I2CD08}: Clock and AC Timing Control Register
{I2CD0C}: Interrupt Control Register
{I2CD10}: Interrupt Status Register
{I2CD14}: Command/Status Register
{I2CD18}: Slave Device Address Register
{I2CD1C}: Pool Buffer Control Register
{I2CD20}: Transmit/Receive Byte Buffer Register
{I2CD24}: DMA Mode Buffer Address Register
{I2CD28}: DMA Transfer Length Register
{I2CD2C}: Original DMA Mode Buffer Address Setting
{I2CD30}: Original DMA Transfer Length Setting and Final Status

New Register mode
{I2CC00}: Master/Slave Function Control Register
{I2CC04}: Master/Slave Clock and AC Timing Control Register
{I2CC08}: Master/Slave Transmit/Receive Byte Buffer Register
{I2CC0C}: Master/Slave Pool Buffer Control Register
{I2CM10}: Master Interrupt Control Register
{I2CM14}: Master Interrupt Status Register
{I2CM18}: Master Command/Status Register
{I2CM1C}: Master DMA Buffer Length Register
{I2CS20}: Slave~ Interrupt Control Register
{I2CS24}: Slave~ Interrupt Status Register
{I2CS28}: Slave~ Command/Status Register
{I2CS2C}: Slave~ DMA Buffer Length Register
{I2CM30}: Master DMA Mode Tx Buffer Base Address
{I2CM34}: Master DMA Mode Rx Buffer Base Address
{I2CS38}: Slave~ DMA Mode Tx Buffer Base Address
{I2CS3C}: Slave~ DMA Mode Rx Buffer Base Address
{I2CS40}: Slave Device Address Register
{I2CM48}: Master DMA Length Status Register
{I2CS4C}: Slave  DMA Length Status Register
{I2CC50}: Current DMA Operating Address Status
{I2CC54}: Current DMA Operating Length  Status

Add a new core file(i2c-aspeed-core.c) to avoid device tree
ABI break, allow both old and new device trees using the same
compatible string "aspeed,ast2600-i2c-bus" to function correctly.

Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
---
 drivers/i2c/busses/Makefile          |    2 +-
 drivers/i2c/busses/i2c-aspeed-core.c |   89 +++
 drivers/i2c/busses/i2c-aspeed-core.h |   19 +
 drivers/i2c/busses/i2c-aspeed.c      |   43 +-
 drivers/i2c/busses/i2c-ast2600.c     | 1018 ++++++++++++++++++++++++++
 5 files changed, 1136 insertions(+), 35 deletions(-)
 create mode 100644 drivers/i2c/busses/i2c-aspeed-core.c
 create mode 100644 drivers/i2c/busses/i2c-aspeed-core.h
 create mode 100644 drivers/i2c/busses/i2c-ast2600.c

diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile
index fb985769f5ff..606b35196960 100644
--- a/drivers/i2c/busses/Makefile
+++ b/drivers/i2c/busses/Makefile
@@ -37,7 +37,7 @@ obj-$(CONFIG_I2C_POWERMAC)	+= i2c-powermac.o
 obj-$(CONFIG_I2C_ALTERA)	+= i2c-altera.o
 obj-$(CONFIG_I2C_AMD_MP2)	+= i2c-amd-mp2-pci.o i2c-amd-mp2-plat.o
 obj-$(CONFIG_I2C_AMD_ASF)	+= i2c-amd-asf-plat.o
-obj-$(CONFIG_I2C_ASPEED)	+= i2c-aspeed.o
+obj-$(CONFIG_I2C_ASPEED)	+= i2c-aspeed.o i2c-ast2600.o i2c-aspeed-core.o
 obj-$(CONFIG_I2C_AT91)		+= i2c-at91.o
 i2c-at91-y			:= i2c-at91-core.o i2c-at91-master.o
 i2c-at91-$(CONFIG_I2C_AT91_SLAVE_EXPERIMENTAL)	+= i2c-at91-slave.o
diff --git a/drivers/i2c/busses/i2c-aspeed-core.c b/drivers/i2c/busses/i2c-aspeed-core.c
new file mode 100644
index 000000000000..a2878e1273ed
--- /dev/null
+++ b/drivers/i2c/busses/i2c-aspeed-core.c
@@ -0,0 +1,89 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ASPEED I2C core driver
+ *
+ * Copyright (C) ASPEED Technology Inc.
+ */
+
+#include <linux/module.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+
+#include "i2c-aspeed-core.h"
+
+struct aspeed_i2c_core_priv {
+	void (*remove)(struct platform_device *pdev);
+	void *bus_data;
+};
+
+static const struct of_device_id aspeed_i2c_of_match[] = {
+	{
+		.compatible = "aspeed,ast2400-i2c-bus",
+		.data = (const void *)AST2400_I2C
+	},
+	{
+		.compatible = "aspeed,ast2500-i2c-bus",
+		.data = (const void *)AST2500_I2C
+	},
+	{
+		.compatible = "aspeed,ast2600-i2c-bus",
+		.data = (const void *)AST2600_I2C
+	},
+	{ }
+};
+
+MODULE_DEVICE_TABLE(of, aspeed_i2c_of_match);
+
+static int aspeed_i2c_core_probe(struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct aspeed_i2c_core_priv *priv;
+	const struct of_device_id *match;
+	int ret;
+
+	priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+	if (!priv)
+		return -ENOMEM;
+
+	match = of_match_device(aspeed_i2c_of_match, dev);
+	if (!match)
+		return -ENODEV;
+
+	if (device_is_compatible(dev, "aspeed,ast2600-i2c-bus") &&
+	    device_property_present(dev, "aspeed,global-regs")) {
+		ret = ast2600_i2c_probe(match, pdev);
+		priv->remove = ast2600_i2c_remove;
+	} else {
+		ret = aspeed_i2c_probe_bus(match, pdev);
+		priv->remove = aspeed_i2c_remove_bus;
+	}
+
+	priv->bus_data = platform_get_drvdata(pdev);
+	platform_set_drvdata(pdev, priv);
+	return ret;
+}
+
+static void aspeed_i2c_core_remove(struct platform_device *pdev)
+{
+	struct aspeed_i2c_core_priv *priv = platform_get_drvdata(pdev);
+
+	if (!priv || !priv->remove)
+		return;
+
+	platform_set_drvdata(pdev, priv->bus_data);
+	return priv->remove(pdev);
+}
+
+static struct platform_driver aspeed_i2c_driver = {
+	.probe  = aspeed_i2c_core_probe,
+	.remove = aspeed_i2c_core_remove,
+	.driver = {
+		.name           = "i2c-aspeed-core",
+		.of_match_table = aspeed_i2c_of_match,
+	},
+};
+module_platform_driver(aspeed_i2c_driver);
+
+MODULE_AUTHOR("Ryan Chen <ryan_chen@aspeedtech.com>");
+MODULE_DESCRIPTION("Unified ASPEED I2C driver (AST24xx/AST25xx/AST2600)");
+MODULE_LICENSE("GPL");
diff --git a/drivers/i2c/busses/i2c-aspeed-core.h b/drivers/i2c/busses/i2c-aspeed-core.h
new file mode 100644
index 000000000000..6e0091018985
--- /dev/null
+++ b/drivers/i2c/busses/i2c-aspeed-core.h
@@ -0,0 +1,19 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+#ifndef _I2C_ASPEED_CORE_H
+#define _I2C_ASPEED_CORE_H
+
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+enum i2c_version {
+	AST2400_I2C,
+	AST2500_I2C,
+	AST2600_I2C,
+	AST2700_I2C,
+};
+
+int aspeed_i2c_probe_bus(const struct of_device_id *match, struct platform_device *pdev);
+void aspeed_i2c_remove_bus(struct platform_device *pdev);
+int ast2600_i2c_probe(const struct of_device_id *match, struct platform_device *pdev);
+void ast2600_i2c_remove(struct platform_device *pdev);
+#endif
diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspeed.c
index a26b74c71206..8466c98b6c7b 100644
--- a/drivers/i2c/busses/i2c-aspeed.c
+++ b/drivers/i2c/busses/i2c-aspeed.c
@@ -25,6 +25,8 @@
 #include <linux/reset.h>
 #include <linux/slab.h>
 
+#include "i2c-aspeed-core.h"
+
 /* I2C Register */
 #define ASPEED_I2C_FUN_CTRL_REG				0x00
 #define ASPEED_I2C_AC_TIMING_REG1			0x04
@@ -978,26 +980,9 @@ static int aspeed_i2c_reset(struct aspeed_i2c_bus *bus)
 	return ret;
 }
 
-static const struct of_device_id aspeed_i2c_bus_of_table[] = {
-	{
-		.compatible = "aspeed,ast2400-i2c-bus",
-		.data = aspeed_i2c_24xx_get_clk_reg_val,
-	},
-	{
-		.compatible = "aspeed,ast2500-i2c-bus",
-		.data = aspeed_i2c_25xx_get_clk_reg_val,
-	},
-	{
-		.compatible = "aspeed,ast2600-i2c-bus",
-		.data = aspeed_i2c_25xx_get_clk_reg_val,
-	},
-	{ }
-};
-MODULE_DEVICE_TABLE(of, aspeed_i2c_bus_of_table);
-
-static int aspeed_i2c_probe_bus(struct platform_device *pdev)
+int aspeed_i2c_probe_bus(const struct of_device_id *match,
+			 struct platform_device *pdev)
 {
-	const struct of_device_id *match;
 	struct aspeed_i2c_bus *bus;
 	struct clk *parent_clk;
 	int irq, ret;
@@ -1033,12 +1018,10 @@ static int aspeed_i2c_probe_bus(struct platform_device *pdev)
 		bus->bus_frequency = I2C_MAX_STANDARD_MODE_FREQ;
 	}
 
-	match = of_match_node(aspeed_i2c_bus_of_table, pdev->dev.of_node);
-	if (!match)
+	if ((enum i2c_version)(uintptr_t)match->data == AST2400_I2C)
 		bus->get_clk_reg_val = aspeed_i2c_24xx_get_clk_reg_val;
 	else
-		bus->get_clk_reg_val = (u32 (*)(struct device *, u32))
-				match->data;
+		bus->get_clk_reg_val = aspeed_i2c_25xx_get_clk_reg_val;
 
 	/* Initialize the I2C adapter */
 	spin_lock_init(&bus->lock);
@@ -1081,8 +1064,9 @@ static int aspeed_i2c_probe_bus(struct platform_device *pdev)
 
 	return 0;
 }
+EXPORT_SYMBOL_GPL(aspeed_i2c_probe_bus);
 
-static void aspeed_i2c_remove_bus(struct platform_device *pdev)
+void aspeed_i2c_remove_bus(struct platform_device *pdev)
 {
 	struct aspeed_i2c_bus *bus = platform_get_drvdata(pdev);
 	unsigned long flags;
@@ -1099,16 +1083,7 @@ static void aspeed_i2c_remove_bus(struct platform_device *pdev)
 
 	i2c_del_adapter(&bus->adap);
 }
-
-static struct platform_driver aspeed_i2c_bus_driver = {
-	.probe		= aspeed_i2c_probe_bus,
-	.remove		= aspeed_i2c_remove_bus,
-	.driver		= {
-		.name		= "aspeed-i2c-bus",
-		.of_match_table	= aspeed_i2c_bus_of_table,
-	},
-};
-module_platform_driver(aspeed_i2c_bus_driver);
+EXPORT_SYMBOL_GPL(aspeed_i2c_remove_bus);
 
 MODULE_AUTHOR("Brendan Higgins <brendanhiggins@google.com>");
 MODULE_DESCRIPTION("Aspeed I2C Bus Driver");
diff --git a/drivers/i2c/busses/i2c-ast2600.c b/drivers/i2c/busses/i2c-ast2600.c
new file mode 100644
index 000000000000..ad9117760ba1
--- /dev/null
+++ b/drivers/i2c/busses/i2c-ast2600.c
@@ -0,0 +1,1018 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * ASPEED AST2600 new register set I2C controller driver
+ *
+ * Copyright (C) ASPEED Technology Inc.
+ */
+#include <linux/array_size.h>
+#include <linux/bits.h>
+#include <linux/clk.h>
+#include <linux/completion.h>
+#include <linux/delay.h>
+#include <linux/dma-mapping.h>
+#include <linux/err.h>
+#include <linux/i2c.h>
+#include <linux/i2c-smbus.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/minmax.h>
+#include <linux/mfd/syscon.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/property.h>
+#include <linux/regmap.h>
+#include <linux/reset.h>
+#include <linux/slab.h>
+#include <linux/string_helpers.h>
+#include <linux/unaligned.h>
+
+#include "i2c-aspeed-core.h"
+
+#define AST2600_I2CG_ISR			0x00
+#define AST2600_I2CG_SLAVE_ISR		0x04
+#define AST2600_I2CG_OWNER		0x08
+#define AST2600_I2CG_CTRL		0x0C
+#define AST2600_I2CG_CLK_DIV_CTRL	0x10
+
+#define AST2600_I2CG_SLAVE_PKT_NAK	BIT(4)
+#define AST2600_I2CG_M_S_SEPARATE_INTR	BIT(3)
+#define AST2600_I2CG_CTRL_NEW_REG	BIT(2)
+#define AST2600_I2CG_CTRL_NEW_CLK_DIV	BIT(1)
+#define AST2600_GLOBAL_INIT	\
+	(AST2600_I2CG_CTRL_NEW_REG | AST2600_I2CG_CTRL_NEW_CLK_DIV)
+/*
+ * APB clk : 100Mhz
+ * div	: scl		: baseclk [APB/((div/2) + 1)] : tBuf [1/bclk * 16]
+ * I2CG10[31:24] base clk4 for i2c auto recovery timeout counter (0xC6)
+ * I2CG10[23:16] base clk3 for Standard-mode (100Khz) min tBuf 4.7us
+ * 0x3c : 100.8Khz	: 3.225Mhz					  : 4.96us
+ * 0x3d : 99.2Khz	: 3.174Mhz					  : 5.04us
+ * 0x3e : 97.65Khz	: 3.125Mhz					  : 5.12us
+ * 0x40 : 97.75Khz	: 3.03Mhz					  : 5.28us
+ * 0x41 : 99.5Khz	: 2.98Mhz					  : 5.36us (default)
+ * I2CG10[15:8] base clk2 for Fast-mode (400Khz) min tBuf 1.3us
+ * 0x12 : 400Khz	: 10Mhz						  : 1.6us
+ * I2CG10[7:0] base clk1 for Fast-mode Plus (1Mhz) min tBuf 0.5us
+ * 0x08 : 1Mhz		: 20Mhz						  : 0.8us
+ */
+#define I2CCG_DIV_CTRL 0xC6411208
+
+/* 0x00 : I2CC Controller/Target Function Control Register  */
+#define AST2600_I2CC_FUN_CTRL		0x00
+#define AST2600_I2CC_SLAVE_ADDR_RX_EN		BIT(20)
+#define AST2600_I2CC_MASTER_RETRY_MASK		GENMASK(19, 18)
+#define AST2600_I2CC_MASTER_RETRY(x)		(((x) & GENMASK(1, 0)) << 18)
+#define AST2600_I2CC_BUS_AUTO_RELEASE		BIT(17)
+#define AST2600_I2CC_M_SDA_LOCK_EN			BIT(16)
+#define AST2600_I2CC_MULTI_MASTER_DIS		BIT(15)
+#define AST2600_I2CC_M_SCL_DRIVE_EN			BIT(14)
+#define AST2600_I2CC_MSB_STS				BIT(9)
+#define AST2600_I2CC_SDA_DRIVE_1T_EN		BIT(8)
+#define AST2600_I2CC_M_SDA_DRIVE_1T_EN		BIT(7)
+#define AST2600_I2CC_M_HIGH_SPEED_EN		BIT(6)
+/* reserver 5 : 2 */
+#define AST2600_I2CC_SLAVE_EN			BIT(1)
+#define AST2600_I2CC_MASTER_EN			BIT(0)
+
+/* 0x04 : I2CC Controller/Target Clock and AC Timing Control Register #1 */
+#define AST2600_I2CC_AC_TIMING		0x04
+#define AST2600_I2CC_TTIMEOUT(x)			(((x) & GENMASK(4, 0)) << 24)
+#define AST2600_I2CC_TCKHIGHMIN(x)			(((x) & GENMASK(3, 0)) << 20)
+#define AST2600_I2CC_TCKHIGH(x)			(((x) & GENMASK(3, 0)) << 16)
+#define AST2600_I2CC_TCKLOW(x)			(((x) & GENMASK(3, 0)) << 12)
+#define AST2600_I2CC_THDDAT(x)			(((x) & GENMASK(1, 0)) << 10)
+#define AST2600_I2CC_TOUTBASECLK(x)			(((x) & GENMASK(1, 0)) << 8)
+#define AST2600_I2CC_TBASECLK(x)			((x) & GENMASK(3, 0))
+
+/* 0x08 : I2CC Controller/Target Transmit/Receive Byte Buffer Register */
+#define AST2600_I2CC_STS_AND_BUFF		0x08
+#define AST2600_I2CC_TX_DIR_MASK			GENMASK(31, 29)
+#define AST2600_I2CC_SDA_OE				BIT(28)
+#define AST2600_I2CC_SDA_O				BIT(27)
+#define AST2600_I2CC_SCL_OE				BIT(26)
+#define AST2600_I2CC_SCL_O				BIT(25)
+
+#define AST2600_I2CC_SCL_LINE_STS			BIT(18)
+#define AST2600_I2CC_SDA_LINE_STS			BIT(17)
+#define AST2600_I2CC_BUS_BUSY_STS			BIT(16)
+
+#define AST2600_I2CC_GET_RX_BUFF(x)			(((x) >> 8) & GENMASK(7, 0))
+
+/* 0x0C : I2CC Controller/Target Pool Buffer Control Register  */
+#define AST2600_I2CC_BUFF_CTRL		0x0C
+#define AST2600_I2CC_GET_RX_BUF_LEN(x)      (((x) & GENMASK(29, 24)) >> 24)
+#define AST2600_I2CC_SET_RX_BUF_LEN(x)		(((((x) - 1) & GENMASK(4, 0)) << 16) | BIT(0))
+#define AST2600_I2CC_SET_TX_BUF_LEN(x)		(((((x) - 1) & GENMASK(4, 0)) << 8) | BIT(0))
+#define AST2600_I2CC_GET_TX_BUF_LEN(x)      ((((x) & GENMASK(12, 8)) >> 8) + 1)
+
+/* 0x10 : I2CM Controller Interrupt Control Register */
+#define AST2600_I2CM_IER			0x10
+/* 0x14 : I2CM Controller Interrupt Status Register   : WC */
+#define AST2600_I2CM_ISR			0x14
+
+#define AST2600_I2CM_PKT_TIMEOUT			BIT(18)
+#define AST2600_I2CM_PKT_ERROR			BIT(17)
+#define AST2600_I2CM_PKT_DONE			BIT(16)
+
+#define AST2600_I2CM_BUS_RECOVER_FAIL		BIT(15)
+#define AST2600_I2CM_SDA_DL_TO			BIT(14)
+#define AST2600_I2CM_BUS_RECOVER			BIT(13)
+#define AST2600_I2CM_SMBUS_ALT			BIT(12)
+
+#define AST2600_I2CM_SCL_LOW_TO			BIT(6)
+#define AST2600_I2CM_ABNORMAL			BIT(5)
+#define AST2600_I2CM_NORMAL_STOP			BIT(4)
+#define AST2600_I2CM_ARBIT_LOSS			BIT(3)
+#define AST2600_I2CM_RX_DONE			BIT(2)
+#define AST2600_I2CM_TX_NAK				BIT(1)
+#define AST2600_I2CM_TX_ACK				BIT(0)
+
+/* 0x18 : I2CM Controller Command/Status Register   */
+#define AST2600_I2CM_CMD_STS		0x18
+#define AST2600_I2CM_PKT_ADDR(x)			(((x) & GENMASK(6, 0)) << 24)
+#define AST2600_I2CM_PKT_EN				BIT(16)
+#define AST2600_I2CM_SDA_OE_OUT_DIR			BIT(15)
+#define AST2600_I2CM_SDA_O_OUT_DIR			BIT(14)
+#define AST2600_I2CM_SCL_OE_OUT_DIR			BIT(13)
+#define AST2600_I2CM_SCL_O_OUT_DIR			BIT(12)
+#define AST2600_I2CM_RECOVER_CMD_EN			BIT(11)
+
+#define AST2600_I2CM_RX_DMA_EN			BIT(9)
+#define AST2600_I2CM_TX_DMA_EN			BIT(8)
+/* Command Bit */
+#define AST2600_I2CM_RX_BUFF_EN			BIT(7)
+#define AST2600_I2CM_TX_BUFF_EN			BIT(6)
+#define AST2600_I2CM_STOP_CMD			BIT(5)
+#define AST2600_I2CM_RX_CMD_LAST			BIT(4)
+#define AST2600_I2CM_RX_CMD				BIT(3)
+
+#define AST2600_I2CM_TX_CMD				BIT(1)
+#define AST2600_I2CM_START_CMD			BIT(0)
+
+/* 0x1C : I2CM Controller DMA Transfer Length Register	 */
+#define AST2600_I2CM_DMA_LEN		0x1C
+/* Tx Rx support length 1 ~ 4096 */
+#define AST2600_I2CM_SET_RX_DMA_LEN(x)	((((x) & GENMASK(11, 0)) << 16) | BIT(31))
+#define AST2600_I2CM_SET_TX_DMA_LEN(x)	(((x) & GENMASK(11, 0)) | BIT(15))
+
+/* 0x20 : I2CS Target Interrupt Control Register   */
+#define AST2600_I2CS_IER			0x20
+/* 0x24 : I2CS Target Interrupt Status Register	 */
+#define AST2600_I2CS_ISR			0x24
+
+#define AST2600_I2CS_ADDR_INDICATE_MASK	GENMASK(31, 30)
+#define AST2600_I2CS_SLAVE_PENDING			BIT(29)
+
+#define AST2600_I2CS_WAIT_TX_DMA			BIT(25)
+#define AST2600_I2CS_WAIT_RX_DMA			BIT(24)
+
+#define AST2600_I2CS_ADDR3_NAK			BIT(22)
+#define AST2600_I2CS_ADDR2_NAK			BIT(21)
+#define AST2600_I2CS_ADDR1_NAK			BIT(20)
+
+#define AST2600_I2CS_ADDR_MASK			GENMASK(19, 18)
+#define AST2600_I2CS_PKT_ERROR			BIT(17)
+#define AST2600_I2CS_PKT_DONE			BIT(16)
+#define AST2600_I2CS_INACTIVE_TO			BIT(15)
+
+#define AST2600_I2CS_SLAVE_MATCH			BIT(7)
+#define AST2600_I2CS_ABNOR_STOP			BIT(5)
+#define AST2600_I2CS_STOP				BIT(4)
+#define AST2600_I2CS_RX_DONE_NAK			BIT(3)
+#define AST2600_I2CS_RX_DONE			BIT(2)
+#define AST2600_I2CS_TX_NAK				BIT(1)
+#define AST2600_I2CS_TX_ACK				BIT(0)
+
+/* 0x28 : I2CS Target CMD/Status Register   */
+#define AST2600_I2CS_CMD_STS		0x28
+#define AST2600_I2CS_ACTIVE_ALL			GENMASK(18, 17)
+#define AST2600_I2CS_PKT_MODE_EN			BIT(16)
+#define AST2600_I2CS_AUTO_NAK_NOADDR		BIT(15)
+#define AST2600_I2CS_AUTO_NAK_EN			BIT(14)
+
+#define AST2600_I2CS_ALT_EN				BIT(10)
+#define AST2600_I2CS_RX_DMA_EN			BIT(9)
+#define AST2600_I2CS_TX_DMA_EN			BIT(8)
+#define AST2600_I2CS_RX_BUFF_EN			BIT(7)
+#define AST2600_I2CS_TX_BUFF_EN			BIT(6)
+#define AST2600_I2CS_RX_CMD_LAST			BIT(4)
+
+#define AST2600_I2CS_TX_CMD				BIT(2)
+
+#define AST2600_I2CS_DMA_LEN		0x2C
+#define AST2600_I2CS_SET_RX_DMA_LEN(x)	(((((x) - 1) & GENMASK(11, 0)) << 16) | BIT(31))
+#define AST2600_I2CS_SET_TX_DMA_LEN(x)	((((x) - 1) & GENMASK(11, 0)) | BIT(15))
+
+/* I2CM Controller DMA Tx Buffer Register   */
+#define AST2600_I2CM_TX_DMA			0x30
+/* I2CM Controller DMA Rx Buffer Register	*/
+#define AST2600_I2CM_RX_DMA			0x34
+/* I2CS Target DMA Tx Buffer Register   */
+#define AST2600_I2CS_TX_DMA			0x38
+/* I2CS Target DMA Rx Buffer Register   */
+#define AST2600_I2CS_RX_DMA			0x3C
+
+#define AST2600_I2CS_ADDR_CTRL		0x40
+
+#define	AST2600_I2CS_ADDR3_MASK		GENMASK(22, 16)
+#define	AST2600_I2CS_ADDR2_MASK		GENMASK(14, 8)
+#define	AST2600_I2CS_ADDR1_MASK		GENMASK(6, 0)
+
+#define AST2600_I2CM_DMA_LEN_STS		0x48
+#define AST2600_I2CS_DMA_LEN_STS		0x4C
+
+#define AST2600_I2C_GET_TX_DMA_LEN(x)		((x) & GENMASK(12, 0))
+#define AST2600_I2C_GET_RX_DMA_LEN(x)        (((x) & GENMASK(28, 16)) >> 16)
+
+/* 0x40 : Target Device Address Register */
+#define AST2600_I2CS_ADDR3_ENABLE			BIT(23)
+#define AST2600_I2CS_ADDR3(x)			((x) << 16)
+#define AST2600_I2CS_ADDR2_ENABLE			BIT(15)
+#define AST2600_I2CS_ADDR2(x)			((x) << 8)
+#define AST2600_I2CS_ADDR1_ENABLE			BIT(7)
+#define AST2600_I2CS_ADDR1(x)			(x)
+
+#define I2C_TARGET_MSG_BUF_SIZE		256
+
+#define AST2600_I2C_DMA_SIZE		4096
+
+#define CONTROLLER_TRIGGER_LAST_STOP	(AST2600_I2CM_RX_CMD_LAST | AST2600_I2CM_STOP_CMD)
+#define TARGET_TRIGGER_CMD	(AST2600_I2CS_ACTIVE_ALL | AST2600_I2CS_PKT_MODE_EN)
+
+#define AST_I2C_TIMEOUT_CLK		0x1
+
+enum xfer_mode {
+	BYTE_MODE,
+	BUFF_MODE,
+	DMA_MODE,
+};
+
+struct ast2600_i2c_bus {
+	struct i2c_adapter	adap;
+	struct device		*dev;
+	void __iomem		*reg_base;
+	struct regmap		*global_regs;
+	struct clk		*clk;
+	struct i2c_timings	timing_info;
+	struct completion	cmd_complete;
+	struct i2c_msg		*msgs;
+	u8			*controller_dma_safe_buf;
+	dma_addr_t		controller_dma_addr;
+	u32			apb_clk;
+	u32			timeout;
+	int			irq;
+	int			cmd_err;
+	int			msgs_index;
+	int			msgs_count;
+	int			controller_xfer_cnt;
+	size_t			buf_index;
+	size_t			buf_size;
+	enum xfer_mode		mode;
+	bool			multi_master;
+	/* Buffer mode */
+	void __iomem		*buf_base;
+	struct i2c_smbus_alert_setup	alert_data;
+};
+
+static u32 ast2600_select_i2c_clock(struct ast2600_i2c_bus *i2c_bus)
+{
+	unsigned long base_clk[16];
+	int baseclk_idx = 0;
+	int divisor = 0;
+	u32 clk_div_reg;
+	u32 scl_low;
+	u32 scl_high;
+	u32 data;
+
+	regmap_read(i2c_bus->global_regs, AST2600_I2CG_CLK_DIV_CTRL, &clk_div_reg);
+
+	for (int i = 0; i < ARRAY_SIZE(base_clk); i++) {
+		if (i == 0)
+			base_clk[i] = i2c_bus->apb_clk;
+		else if (i < 5)
+			base_clk[i] = (i2c_bus->apb_clk * 2) /
+			   (((clk_div_reg >> ((i - 1) * 8)) & GENMASK(7, 0)) + 2);
+		else
+			base_clk[i] = base_clk[4] >> (i - 4);
+
+		if ((base_clk[i] / i2c_bus->timing_info.bus_freq_hz) <= 32) {
+			baseclk_idx = i;
+			divisor = DIV_ROUND_UP(base_clk[i], i2c_bus->timing_info.bus_freq_hz);
+			break;
+		}
+	}
+	baseclk_idx = min(baseclk_idx, 15);
+	divisor = min(divisor, 32);
+	scl_low = min(divisor * 9 / 16 - 1, 15);
+	scl_high = (divisor - scl_low - 2) & GENMASK(3, 0);
+	data = (scl_high - 1) << 20 | scl_high << 16 | scl_low << 12 | baseclk_idx;
+	if (i2c_bus->timeout) {
+		data |= AST2600_I2CC_TOUTBASECLK(AST_I2C_TIMEOUT_CLK);
+		data |= AST2600_I2CC_TTIMEOUT(i2c_bus->timeout);
+	}
+
+	return data;
+}
+
+static int ast2600_i2c_recover_bus(struct ast2600_i2c_bus *i2c_bus)
+{
+	u32 state = readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+	int ret = 0;
+	u32 ctrl;
+	int r;
+
+	dev_dbg(i2c_bus->dev, "%d-bus recovery bus [%x]\n", i2c_bus->adap.nr, state);
+
+	ctrl = readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+
+	/* Disable controller */
+	writel(ctrl & ~(AST2600_I2CC_MASTER_EN | AST2600_I2CC_SLAVE_EN),
+	       i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+
+	writel(readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL) | AST2600_I2CC_MASTER_EN,
+	       i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+
+	reinit_completion(&i2c_bus->cmd_complete);
+	i2c_bus->cmd_err = 0;
+
+	/* Check 0x14's SDA and SCL status */
+	state = readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+	if (!(state & AST2600_I2CC_SDA_LINE_STS) && (state & AST2600_I2CC_SCL_LINE_STS)) {
+		writel(AST2600_I2CM_RECOVER_CMD_EN, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+		r = wait_for_completion_timeout(&i2c_bus->cmd_complete, i2c_bus->adap.timeout);
+		if (r == 0) {
+			dev_dbg(i2c_bus->dev, "recovery timed out\n");
+			writel(ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+			return -ETIMEDOUT;
+		} else if (i2c_bus->cmd_err) {
+			dev_dbg(i2c_bus->dev, "recovery error\n");
+			ret = -EPROTO;
+		}
+	}
+
+	/* Recovery done */
+	state = readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+	if (state & AST2600_I2CC_BUS_BUSY_STS) {
+		dev_dbg(i2c_bus->dev, "Can't recover bus [%x]\n", state);
+		ret = -EPROTO;
+	}
+
+	/* restore original controller setting */
+	writel(ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+	return ret;
+}
+
+static int ast2600_i2c_setup_dma_tx(u32 cmd, struct ast2600_i2c_bus *i2c_bus)
+{
+	struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+	int xfer_len = msg->len - i2c_bus->controller_xfer_cnt;
+	int ret;
+
+	cmd |= AST2600_I2CM_PKT_EN;
+
+	if (xfer_len > AST2600_I2C_DMA_SIZE)
+		xfer_len = AST2600_I2C_DMA_SIZE;
+	else if (i2c_bus->msgs_index + 1 == i2c_bus->msgs_count)
+		cmd |= AST2600_I2CM_STOP_CMD;
+
+	if (cmd & AST2600_I2CM_START_CMD) {
+		cmd |= AST2600_I2CM_PKT_ADDR(msg->addr);
+		if (xfer_len) {
+			i2c_bus->controller_dma_safe_buf = i2c_get_dma_safe_msg_buf(msg, 1);
+			if (!i2c_bus->controller_dma_safe_buf)
+				return -ENOMEM;
+			i2c_bus->controller_dma_addr =
+				dma_map_single(i2c_bus->dev, i2c_bus->controller_dma_safe_buf,
+					       msg->len, DMA_TO_DEVICE);
+			ret = dma_mapping_error(i2c_bus->dev, i2c_bus->controller_dma_addr);
+			if (ret) {
+				i2c_put_dma_safe_msg_buf(i2c_bus->controller_dma_safe_buf, msg,
+							 false);
+				i2c_bus->controller_dma_safe_buf = NULL;
+				return ret;
+			}
+		}
+	}
+
+	if (xfer_len) {
+		cmd |= AST2600_I2CM_TX_DMA_EN | AST2600_I2CM_TX_CMD;
+		writel(AST2600_I2CM_SET_TX_DMA_LEN(xfer_len - 1),
+		       i2c_bus->reg_base + AST2600_I2CM_DMA_LEN);
+		writel(i2c_bus->controller_dma_addr + i2c_bus->controller_xfer_cnt,
+		       i2c_bus->reg_base + AST2600_I2CM_TX_DMA);
+	}
+
+	writel(cmd, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+
+	return 0;
+}
+
+static int ast2600_i2c_setup_buff_tx(u32 cmd, struct ast2600_i2c_bus *i2c_bus)
+{
+	struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+	int xfer_len = msg->len - i2c_bus->controller_xfer_cnt;
+	u32 wbuf_dword;
+	int i;
+
+	cmd |= AST2600_I2CM_PKT_EN;
+
+	if (xfer_len > i2c_bus->buf_size)
+		xfer_len = i2c_bus->buf_size;
+	else if (i2c_bus->msgs_index + 1 == i2c_bus->msgs_count)
+		cmd |= AST2600_I2CM_STOP_CMD;
+
+	if (cmd & AST2600_I2CM_START_CMD)
+		cmd |= AST2600_I2CM_PKT_ADDR(msg->addr);
+
+	if (xfer_len) {
+		cmd |= AST2600_I2CM_TX_BUFF_EN | AST2600_I2CM_TX_CMD;
+		/*
+		 * The controller's buffer register supports dword writes only.
+		 * Therefore, write dwords to the buffer register in a 4-byte aligned,
+		 * and write the remaining unaligned data at the end.
+		 */
+		for (i = 0; i < xfer_len; i += 4) {
+			int xfer_cnt = i2c_bus->controller_xfer_cnt + i;
+
+			switch (min(xfer_len - i, 4) % 4) {
+			case 1:
+				wbuf_dword = msg->buf[xfer_cnt];
+				break;
+			case 2:
+				wbuf_dword = get_unaligned_le16(&msg->buf[xfer_cnt]);
+				break;
+			case 3:
+				wbuf_dword = get_unaligned_le24(&msg->buf[xfer_cnt]);
+				break;
+			default:
+				wbuf_dword = get_unaligned_le32(&msg->buf[xfer_cnt]);
+				break;
+			}
+			writel(wbuf_dword, i2c_bus->buf_base + i);
+		}
+		writel(AST2600_I2CC_SET_TX_BUF_LEN(xfer_len),
+		       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+	}
+
+	writel(cmd, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+
+	return 0;
+}
+
+static int ast2600_i2c_setup_byte_tx(u32 cmd, struct ast2600_i2c_bus *i2c_bus)
+{
+	struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+	int xfer_len;
+
+	xfer_len = msg->len - i2c_bus->controller_xfer_cnt;
+
+	cmd |= AST2600_I2CM_PKT_EN;
+
+	if (cmd & AST2600_I2CM_START_CMD)
+		cmd |= AST2600_I2CM_PKT_ADDR(msg->addr);
+
+	if ((i2c_bus->msgs_index + 1 == i2c_bus->msgs_count) &&
+	    ((i2c_bus->controller_xfer_cnt + 1) == msg->len))
+		cmd |= AST2600_I2CM_STOP_CMD;
+
+	if (xfer_len) {
+		cmd |= AST2600_I2CM_TX_CMD;
+		writel(msg->buf[i2c_bus->controller_xfer_cnt],
+		       i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+	}
+
+	writel(cmd, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+
+	return 0;
+}
+
+static int ast2600_i2c_setup_dma_rx(u32 cmd, struct ast2600_i2c_bus *i2c_bus)
+{
+	struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+	int xfer_len = msg->len - i2c_bus->controller_xfer_cnt;
+	int ret;
+
+	cmd |= AST2600_I2CM_PKT_EN | AST2600_I2CM_RX_DMA_EN | AST2600_I2CM_RX_CMD;
+
+	if (msg->flags & I2C_M_RECV_LEN)
+		xfer_len = 1;
+	else if (xfer_len > AST2600_I2C_DMA_SIZE)
+		xfer_len = AST2600_I2C_DMA_SIZE;
+	else if (i2c_bus->msgs_index + 1 == i2c_bus->msgs_count)
+		cmd |= CONTROLLER_TRIGGER_LAST_STOP;
+
+	writel(AST2600_I2CM_SET_RX_DMA_LEN(xfer_len - 1), i2c_bus->reg_base + AST2600_I2CM_DMA_LEN);
+
+	if (cmd & AST2600_I2CM_START_CMD) {
+		cmd |= AST2600_I2CM_PKT_ADDR(msg->addr);
+		i2c_bus->controller_dma_safe_buf = i2c_get_dma_safe_msg_buf(msg, 1);
+		if (!i2c_bus->controller_dma_safe_buf)
+			return -ENOMEM;
+		if (msg->flags & I2C_M_RECV_LEN)
+			i2c_bus->controller_dma_addr =
+				dma_map_single(i2c_bus->dev, i2c_bus->controller_dma_safe_buf,
+					       I2C_SMBUS_BLOCK_MAX + 3, DMA_FROM_DEVICE);
+		else
+			i2c_bus->controller_dma_addr =
+				dma_map_single(i2c_bus->dev, i2c_bus->controller_dma_safe_buf,
+					       msg->len, DMA_FROM_DEVICE);
+		ret = dma_mapping_error(i2c_bus->dev, i2c_bus->controller_dma_addr);
+		if (ret) {
+			i2c_put_dma_safe_msg_buf(i2c_bus->controller_dma_safe_buf, msg, false);
+			i2c_bus->controller_dma_safe_buf = NULL;
+			return -ENOMEM;
+		}
+	}
+	writel(i2c_bus->controller_dma_addr, i2c_bus->reg_base + AST2600_I2CM_RX_DMA);
+
+	writel(cmd, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+
+	return 0;
+}
+
+static int ast2600_i2c_setup_buff_rx(u32 cmd, struct ast2600_i2c_bus *i2c_bus)
+{
+	struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+	int xfer_len = msg->len - i2c_bus->controller_xfer_cnt;
+
+	cmd |= AST2600_I2CM_PKT_EN | AST2600_I2CM_RX_BUFF_EN | AST2600_I2CM_RX_CMD;
+
+	if (cmd & AST2600_I2CM_START_CMD)
+		cmd |= AST2600_I2CM_PKT_ADDR(msg->addr);
+
+	if (msg->flags & I2C_M_RECV_LEN) {
+		dev_dbg(i2c_bus->dev, "smbus read\n");
+		xfer_len = 1;
+	} else if (xfer_len > i2c_bus->buf_size) {
+		xfer_len = i2c_bus->buf_size;
+	} else if (i2c_bus->msgs_index + 1 == i2c_bus->msgs_count) {
+		cmd |= CONTROLLER_TRIGGER_LAST_STOP;
+	}
+	writel(AST2600_I2CC_SET_RX_BUF_LEN(xfer_len), i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+
+	writel(cmd, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+
+	return 0;
+}
+
+static int ast2600_i2c_setup_byte_rx(u32 cmd, struct ast2600_i2c_bus *i2c_bus)
+{
+	struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+
+	cmd |= AST2600_I2CM_PKT_EN | AST2600_I2CM_RX_CMD;
+
+	if (cmd & AST2600_I2CM_START_CMD)
+		cmd |= AST2600_I2CM_PKT_ADDR(msg->addr);
+
+	if (msg->flags & I2C_M_RECV_LEN) {
+		dev_dbg(i2c_bus->dev, "smbus read\n");
+	} else if ((i2c_bus->msgs_index + 1 == i2c_bus->msgs_count) &&
+		   ((i2c_bus->controller_xfer_cnt + 1) == msg->len)) {
+		cmd |= CONTROLLER_TRIGGER_LAST_STOP;
+	}
+
+	writel(cmd, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+
+	return 0;
+}
+
+static int ast2600_i2c_do_start(struct ast2600_i2c_bus *i2c_bus)
+{
+	struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+
+	/* send start */
+	dev_dbg(i2c_bus->dev, "[%d] %s %d byte%s %s 0x%02x\n",
+		i2c_bus->msgs_index, str_read_write(msg->flags & I2C_M_RD),
+		msg->len, str_plural(msg->len),
+		msg->flags & I2C_M_RD ? "from" : "to", msg->addr);
+
+	i2c_bus->controller_xfer_cnt = 0;
+	i2c_bus->buf_index = 0;
+
+	if (msg->flags & I2C_M_RD) {
+		if (i2c_bus->mode == DMA_MODE)
+			return ast2600_i2c_setup_dma_rx(AST2600_I2CM_START_CMD, i2c_bus);
+		else if (i2c_bus->mode == BUFF_MODE)
+			return ast2600_i2c_setup_buff_rx(AST2600_I2CM_START_CMD, i2c_bus);
+		else
+			return ast2600_i2c_setup_byte_rx(AST2600_I2CM_START_CMD, i2c_bus);
+	} else {
+		if (i2c_bus->mode == DMA_MODE)
+			return ast2600_i2c_setup_dma_tx(AST2600_I2CM_START_CMD, i2c_bus);
+		else if (i2c_bus->mode == BUFF_MODE)
+			return ast2600_i2c_setup_buff_tx(AST2600_I2CM_START_CMD, i2c_bus);
+		else
+			return ast2600_i2c_setup_byte_tx(AST2600_I2CM_START_CMD, i2c_bus);
+	}
+}
+
+static int ast2600_i2c_irq_err_to_errno(u32 irq_status)
+{
+	if (irq_status & AST2600_I2CM_ARBIT_LOSS)
+		return -EAGAIN;
+	if (irq_status & (AST2600_I2CM_SDA_DL_TO | AST2600_I2CM_SCL_LOW_TO))
+		return -EBUSY;
+	if (irq_status & (AST2600_I2CM_ABNORMAL))
+		return -EPROTO;
+
+	return 0;
+}
+
+static void ast2600_i2c_controller_package_irq(struct ast2600_i2c_bus *i2c_bus, u32 sts)
+{
+	struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+	int xfer_len;
+	int i;
+
+	sts &= ~AST2600_I2CM_PKT_DONE;
+	writel(AST2600_I2CM_PKT_DONE, i2c_bus->reg_base + AST2600_I2CM_ISR);
+	switch (sts) {
+	case AST2600_I2CM_PKT_ERROR:
+		i2c_bus->cmd_err = -EAGAIN;
+		complete(&i2c_bus->cmd_complete);
+		break;
+	case AST2600_I2CM_PKT_ERROR | AST2600_I2CM_TX_NAK: /* a0 fix for issue */
+		fallthrough;
+	case AST2600_I2CM_PKT_ERROR | AST2600_I2CM_TX_NAK | AST2600_I2CM_NORMAL_STOP:
+		i2c_bus->cmd_err = -ENXIO;
+		complete(&i2c_bus->cmd_complete);
+		break;
+	case AST2600_I2CM_NORMAL_STOP:
+		/* write 0 byte only have stop isr */
+		i2c_bus->msgs_index++;
+		if (i2c_bus->msgs_index < i2c_bus->msgs_count) {
+			if (ast2600_i2c_do_start(i2c_bus)) {
+				i2c_bus->cmd_err = -ENOMEM;
+				complete(&i2c_bus->cmd_complete);
+			}
+		} else {
+			i2c_bus->cmd_err = i2c_bus->msgs_index;
+			complete(&i2c_bus->cmd_complete);
+		}
+		break;
+	case AST2600_I2CM_TX_ACK:
+	case AST2600_I2CM_TX_ACK | AST2600_I2CM_NORMAL_STOP:
+		if (i2c_bus->mode == DMA_MODE)
+			xfer_len = AST2600_I2C_GET_TX_DMA_LEN(readl(i2c_bus->reg_base +
+							  AST2600_I2CM_DMA_LEN_STS));
+		else if (i2c_bus->mode == BUFF_MODE)
+			xfer_len = AST2600_I2CC_GET_TX_BUF_LEN(readl(i2c_bus->reg_base +
+							   AST2600_I2CC_BUFF_CTRL));
+		else
+			xfer_len = 1;
+
+		i2c_bus->controller_xfer_cnt += xfer_len;
+
+		if (i2c_bus->controller_xfer_cnt == msg->len) {
+			if (i2c_bus->mode == DMA_MODE) {
+				dma_unmap_single(i2c_bus->dev, i2c_bus->controller_dma_addr,
+						 msg->len, DMA_TO_DEVICE);
+				i2c_put_dma_safe_msg_buf(i2c_bus->controller_dma_safe_buf, msg,
+							 true);
+				i2c_bus->controller_dma_safe_buf = NULL;
+			}
+			i2c_bus->msgs_index++;
+			if (i2c_bus->msgs_index == i2c_bus->msgs_count) {
+				i2c_bus->cmd_err = i2c_bus->msgs_index;
+				complete(&i2c_bus->cmd_complete);
+			} else {
+				if (ast2600_i2c_do_start(i2c_bus)) {
+					i2c_bus->cmd_err = -ENOMEM;
+					complete(&i2c_bus->cmd_complete);
+				}
+			}
+		} else {
+			if (i2c_bus->mode == DMA_MODE)
+				ast2600_i2c_setup_dma_tx(0, i2c_bus);
+			else if (i2c_bus->mode == BUFF_MODE)
+				ast2600_i2c_setup_buff_tx(0, i2c_bus);
+			else
+				ast2600_i2c_setup_byte_tx(0, i2c_bus);
+		}
+		break;
+	case AST2600_I2CM_RX_DONE:
+	case AST2600_I2CM_RX_DONE | AST2600_I2CM_NORMAL_STOP:
+		/* do next rx */
+		if (i2c_bus->mode == DMA_MODE) {
+			xfer_len = AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base +
+								    AST2600_I2CM_DMA_LEN_STS));
+		} else if (i2c_bus->mode == BUFF_MODE) {
+			xfer_len = AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
+								     AST2600_I2CC_BUFF_CTRL));
+			for (i = 0; i < xfer_len; i++)
+				msg->buf[i2c_bus->controller_xfer_cnt + i] =
+					readb(i2c_bus->buf_base + 0x10 + i);
+		} else {
+			xfer_len = 1;
+			msg->buf[i2c_bus->controller_xfer_cnt] =
+				AST2600_I2CC_GET_RX_BUFF(readl(i2c_bus->reg_base +
+						     AST2600_I2CC_STS_AND_BUFF));
+		}
+
+		if (msg->flags & I2C_M_RECV_LEN) {
+			u8 recv_len = AST2600_I2CC_GET_RX_BUFF(readl(i2c_bus->reg_base
+						       + AST2600_I2CC_STS_AND_BUFF));
+			msg->len = min_t(unsigned int, recv_len, I2C_SMBUS_BLOCK_MAX);
+			msg->len += ((msg->flags & I2C_CLIENT_PEC) ? 2 : 1);
+			msg->flags &= ~I2C_M_RECV_LEN;
+			if (!recv_len)
+				i2c_bus->controller_xfer_cnt = 0;
+			else
+				i2c_bus->controller_xfer_cnt = 1;
+		} else {
+			i2c_bus->controller_xfer_cnt += xfer_len;
+		}
+
+		if (i2c_bus->controller_xfer_cnt == msg->len) {
+			if (i2c_bus->mode == DMA_MODE) {
+				dma_unmap_single(i2c_bus->dev, i2c_bus->controller_dma_addr,
+						 msg->len, DMA_FROM_DEVICE);
+				i2c_put_dma_safe_msg_buf(i2c_bus->controller_dma_safe_buf,
+							 msg, true);
+				i2c_bus->controller_dma_safe_buf = NULL;
+			}
+
+			i2c_bus->msgs_index++;
+			if (i2c_bus->msgs_index == i2c_bus->msgs_count) {
+				i2c_bus->cmd_err = i2c_bus->msgs_index;
+				complete(&i2c_bus->cmd_complete);
+			} else {
+				if (ast2600_i2c_do_start(i2c_bus)) {
+					i2c_bus->cmd_err = -ENOMEM;
+					complete(&i2c_bus->cmd_complete);
+				}
+			}
+		} else {
+			if (i2c_bus->mode == DMA_MODE)
+				ast2600_i2c_setup_dma_rx(0, i2c_bus);
+			else if (i2c_bus->mode == BUFF_MODE)
+				ast2600_i2c_setup_buff_rx(0, i2c_bus);
+			else
+				ast2600_i2c_setup_byte_rx(0, i2c_bus);
+		}
+		break;
+	default:
+		dev_dbg(i2c_bus->dev, "unhandled sts %x\n", sts);
+		break;
+	}
+}
+
+static int ast2600_i2c_controller_irq(struct ast2600_i2c_bus *i2c_bus)
+{
+	u32 sts = readl(i2c_bus->reg_base + AST2600_I2CM_ISR);
+	u32 ctrl;
+
+	sts &= ~AST2600_I2CM_SMBUS_ALT;
+
+	if (AST2600_I2CM_BUS_RECOVER_FAIL & sts) {
+		writel(AST2600_I2CM_BUS_RECOVER_FAIL, i2c_bus->reg_base + AST2600_I2CM_ISR);
+		ctrl = readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+		writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+		writel(ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+		i2c_bus->cmd_err = -EPROTO;
+		complete(&i2c_bus->cmd_complete);
+		return 1;
+	}
+
+	if (AST2600_I2CM_BUS_RECOVER & sts) {
+		writel(AST2600_I2CM_BUS_RECOVER, i2c_bus->reg_base + AST2600_I2CM_ISR);
+		i2c_bus->cmd_err = 0;
+		complete(&i2c_bus->cmd_complete);
+		return 1;
+	}
+
+	i2c_bus->cmd_err = ast2600_i2c_irq_err_to_errno(sts);
+	if (i2c_bus->cmd_err) {
+		writel(AST2600_I2CM_PKT_DONE, i2c_bus->reg_base + AST2600_I2CM_ISR);
+		complete(&i2c_bus->cmd_complete);
+		return 1;
+	}
+
+	if (AST2600_I2CM_PKT_DONE & sts) {
+		ast2600_i2c_controller_package_irq(i2c_bus, sts);
+		return 1;
+	}
+
+	return 0;
+}
+
+static irqreturn_t ast2600_i2c_bus_irq(int irq, void *dev_id)
+{
+	struct ast2600_i2c_bus *i2c_bus = dev_id;
+
+	return IRQ_RETVAL(ast2600_i2c_controller_irq(i2c_bus));
+}
+
+static int ast2600_i2c_controller_xfer(struct i2c_adapter *adap, struct i2c_msg *msgs, int num)
+{
+	struct ast2600_i2c_bus *i2c_bus = i2c_get_adapdata(adap);
+	unsigned long timeout;
+	int ret;
+
+	if (!i2c_bus->multi_master &&
+	    (readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF) & AST2600_I2CC_BUS_BUSY_STS)) {
+		ret = ast2600_i2c_recover_bus(i2c_bus);
+		if (ret)
+			return ret;
+	}
+
+	i2c_bus->cmd_err = 0;
+	i2c_bus->msgs = msgs;
+	i2c_bus->msgs_index = 0;
+	i2c_bus->msgs_count = num;
+	reinit_completion(&i2c_bus->cmd_complete);
+	ret = ast2600_i2c_do_start(i2c_bus);
+	if (ret)
+		goto controller_out;
+	timeout = wait_for_completion_timeout(&i2c_bus->cmd_complete, i2c_bus->adap.timeout);
+	if (timeout == 0) {
+		u32 ctrl = readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+
+		dev_dbg(i2c_bus->dev, "timeout isr[%x], sts[%x]\n",
+			readl(i2c_bus->reg_base + AST2600_I2CM_ISR),
+			readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF));
+		writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+		writel(ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+
+		if (i2c_bus->multi_master &&
+		    (readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF) &
+		    AST2600_I2CC_BUS_BUSY_STS))
+			ast2600_i2c_recover_bus(i2c_bus);
+
+		ret = -ETIMEDOUT;
+	} else {
+		ret = i2c_bus->cmd_err;
+	}
+
+	dev_dbg(i2c_bus->dev, "bus%d-m: %d end\n", i2c_bus->adap.nr, i2c_bus->cmd_err);
+
+controller_out:
+	if (i2c_bus->mode == DMA_MODE) {
+		if (i2c_bus->controller_dma_safe_buf) {
+			struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
+
+			if (msg->flags & I2C_M_RD)
+				dma_unmap_single(i2c_bus->dev, i2c_bus->controller_dma_addr,
+						 msg->len, DMA_FROM_DEVICE);
+			else
+				dma_unmap_single(i2c_bus->dev, i2c_bus->controller_dma_addr,
+						 msg->len, DMA_TO_DEVICE);
+			i2c_put_dma_safe_msg_buf(i2c_bus->controller_dma_safe_buf, msg, true);
+			i2c_bus->controller_dma_safe_buf = NULL;
+		}
+	}
+
+	return ret;
+}
+
+static void ast2600_i2c_init(struct ast2600_i2c_bus *i2c_bus)
+{
+	struct platform_device *pdev = to_platform_device(i2c_bus->dev);
+	u32 fun_ctrl = AST2600_I2CC_BUS_AUTO_RELEASE | AST2600_I2CC_MASTER_EN;
+
+	/* I2C Reset */
+	writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+
+	i2c_bus->multi_master = device_property_read_bool(&pdev->dev, "multi-master");
+	if (!i2c_bus->multi_master)
+		fun_ctrl |= AST2600_I2CC_MULTI_MASTER_DIS;
+
+	/* Enable Controller Mode */
+	writel(fun_ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+	/* disable target address */
+	writel(0, i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL);
+
+	/* Set AC Timing */
+	writel(ast2600_select_i2c_clock(i2c_bus), i2c_bus->reg_base + AST2600_I2CC_AC_TIMING);
+
+	/* Clear Interrupt */
+	writel(GENMASK(27, 0), i2c_bus->reg_base + AST2600_I2CM_ISR);
+}
+
+static u32 ast2600_i2c_functionality(struct i2c_adapter *adap)
+{
+	return I2C_FUNC_I2C | I2C_FUNC_SMBUS_EMUL | I2C_FUNC_SMBUS_BLOCK_DATA;
+}
+
+static const struct i2c_algorithm i2c_ast2600_algorithm = {
+	.xfer = ast2600_i2c_controller_xfer,
+	.functionality = ast2600_i2c_functionality,
+};
+
+int ast2600_i2c_probe(const struct of_device_id *match, struct platform_device *pdev)
+{
+	struct device *dev = &pdev->dev;
+	struct ast2600_i2c_bus *i2c_bus;
+	struct reset_control *rst;
+	const char *xfer_mode;
+	struct resource *res;
+	u32 global_ctrl;
+	int ret;
+
+	i2c_bus = devm_kzalloc(dev, sizeof(*i2c_bus), GFP_KERNEL);
+	if (!i2c_bus)
+		return -ENOMEM;
+
+	i2c_bus->reg_base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(i2c_bus->reg_base))
+		return PTR_ERR(i2c_bus->reg_base);
+
+	rst = devm_reset_control_get_shared_deasserted(dev, NULL);
+	if (IS_ERR(rst))
+		return dev_err_probe(dev, PTR_ERR(rst), "Missing reset ctrl\n");
+
+	i2c_bus->global_regs =
+		syscon_regmap_lookup_by_phandle(dev_of_node(dev), "aspeed,global-regs");
+	if (IS_ERR(i2c_bus->global_regs))
+		return PTR_ERR(i2c_bus->global_regs);
+
+	regmap_read(i2c_bus->global_regs, AST2600_I2CG_CTRL, &global_ctrl);
+	if ((global_ctrl & AST2600_GLOBAL_INIT) != AST2600_GLOBAL_INIT) {
+		regmap_write(i2c_bus->global_regs, AST2600_I2CG_CTRL, AST2600_GLOBAL_INIT);
+		regmap_write(i2c_bus->global_regs, AST2600_I2CG_CLK_DIV_CTRL, I2CCG_DIV_CTRL);
+	}
+
+	i2c_bus->dev = dev;
+	i2c_bus->mode = BUFF_MODE;
+	if (!device_property_read_string(dev, "aspeed,transfer-mode", &xfer_mode)) {
+		if (!strcmp(xfer_mode, "dma"))
+			i2c_bus->mode = DMA_MODE;
+		else if (!strcmp(xfer_mode, "byte"))
+			i2c_bus->mode = BYTE_MODE;
+		else
+			i2c_bus->mode = BUFF_MODE;
+	}
+
+	if (i2c_bus->mode == BUFF_MODE) {
+		i2c_bus->buf_base = devm_platform_get_and_ioremap_resource(pdev, 1, &res);
+		if (IS_ERR(i2c_bus->buf_base))
+			i2c_bus->mode = BYTE_MODE;
+		else
+			i2c_bus->buf_size = resource_size(res) / 2;
+	}
+
+	/*
+	 * i2c timeout counter: use base clk4 1Mhz,
+	 * per unit: 1/(1000/1024) = 1024us
+	 */
+	ret = device_property_read_u32(dev, "i2c-scl-clk-low-timeout-us", &i2c_bus->timeout);
+	if (!ret)
+		i2c_bus->timeout /= 1024;
+
+	init_completion(&i2c_bus->cmd_complete);
+
+	i2c_bus->irq = platform_get_irq(pdev, 0);
+	if (i2c_bus->irq < 0)
+		return i2c_bus->irq;
+
+	platform_set_drvdata(pdev, i2c_bus);
+
+	i2c_bus->clk = devm_clk_get(i2c_bus->dev, NULL);
+	if (IS_ERR(i2c_bus->clk))
+		return dev_err_probe(i2c_bus->dev, PTR_ERR(i2c_bus->clk), "Can't get clock\n");
+
+	i2c_bus->apb_clk = clk_get_rate(i2c_bus->clk);
+
+	i2c_parse_fw_timings(i2c_bus->dev, &i2c_bus->timing_info, true);
+
+	/* Initialize the I2C adapter */
+	i2c_bus->adap.owner = THIS_MODULE;
+	i2c_bus->adap.algo = &i2c_ast2600_algorithm;
+	i2c_bus->adap.retries = 0;
+	i2c_bus->adap.dev.parent = i2c_bus->dev;
+	device_set_node(&i2c_bus->adap.dev, dev_fwnode(dev));
+	i2c_bus->adap.algo_data = i2c_bus;
+	strscpy(i2c_bus->adap.name, pdev->name);
+	i2c_set_adapdata(&i2c_bus->adap, i2c_bus);
+
+	ast2600_i2c_init(i2c_bus);
+
+	ret = devm_request_irq(dev, i2c_bus->irq, ast2600_i2c_bus_irq, 0,
+			       dev_name(dev), i2c_bus);
+	if (ret < 0)
+		return dev_err_probe(dev, ret, "Unable to request irq %d\n", i2c_bus->irq);
+
+	writel(AST2600_I2CM_PKT_DONE | AST2600_I2CM_BUS_RECOVER,
+	       i2c_bus->reg_base + AST2600_I2CM_IER);
+
+	ret = devm_i2c_add_adapter(dev, &i2c_bus->adap);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(ast2600_i2c_probe);
+
+void ast2600_i2c_remove(struct platform_device *pdev)
+{
+	struct ast2600_i2c_bus *i2c_bus = platform_get_drvdata(pdev);
+
+	/* Disable everything. */
+	writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+	writel(0, i2c_bus->reg_base + AST2600_I2CM_IER);
+}
+EXPORT_SYMBOL_GPL(ast2600_i2c_remove);
+
+MODULE_AUTHOR("Ryan Chen <ryan_chen@aspeedtech.com>");
+MODULE_DESCRIPTION("ASPEED AST2600 I2C Controller Driver");
+MODULE_LICENSE("GPL");
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH v22 4/4] i2c: ast2600: Add target mode support
  2025-11-12  8:56 [PATCH v22 0/4] Add ASPEED AST2600 I2C controller driver Ryan Chen
                   ` (2 preceding siblings ...)
  2025-11-12  8:56 ` [PATCH v22 3/4] i2c: ast2600: Add controller driver for new register layout Ryan Chen
@ 2025-11-12  8:56 ` Ryan Chen
  3 siblings, 0 replies; 6+ messages in thread
From: Ryan Chen @ 2025-11-12  8:56 UTC (permalink / raw)
  To: ryan_chen, bmc-sw, benh, joel, andi.shyti, jk, robh, krzk+dt,
	conor+dt, andrew, p.zabel, andriy.shevchenko, naresh.solanki,
	linux-i2c, openbmc, devicetree, linux-arm-kernel, linux-aspeed,
	linux-kernel

Add target mode support to the AST2600 I2C driver using
new register layout.

Target mode features implemented include:
- Add target interrupt handling
- Address match and response logic
- Separate Tx/Rx DMA address and length configuration

This complements the existing controller-mode support,
enabling dual-role capability.

Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
---
 drivers/i2c/busses/i2c-ast2600.c | 560 +++++++++++++++++++++++++++++++
 1 file changed, 560 insertions(+)

diff --git a/drivers/i2c/busses/i2c-ast2600.c b/drivers/i2c/busses/i2c-ast2600.c
index ad9117760ba1..aa9f2200eeff 100644
--- a/drivers/i2c/busses/i2c-ast2600.c
+++ b/drivers/i2c/busses/i2c-ast2600.c
@@ -83,6 +83,7 @@
 #define AST2600_I2CC_THDDAT(x)			(((x) & GENMASK(1, 0)) << 10)
 #define AST2600_I2CC_TOUTBASECLK(x)			(((x) & GENMASK(1, 0)) << 8)
 #define AST2600_I2CC_TBASECLK(x)			((x) & GENMASK(3, 0))
+#define AST2600_I2CC_AC_TIMING_MASK		GENMASK(23, 0)
 
 /* 0x08 : I2CC Controller/Target Transmit/Receive Byte Buffer Register */
 #define AST2600_I2CC_STS_AND_BUFF		0x08
@@ -272,6 +273,13 @@ struct ast2600_i2c_bus {
 	/* Buffer mode */
 	void __iomem		*buf_base;
 	struct i2c_smbus_alert_setup	alert_data;
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+	/* target structure */
+	int			target_operate;
+	unsigned char	*target_dma_buf;
+	dma_addr_t		target_dma_addr;
+	struct i2c_client	*target;
+#endif
 };
 
 static u32 ast2600_select_i2c_clock(struct ast2600_i2c_bus *i2c_bus)
@@ -362,6 +370,423 @@ static int ast2600_i2c_recover_bus(struct ast2600_i2c_bus *i2c_bus)
 	return ret;
 }
 
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+static void ast2600_i2c_target_packet_dma_irq(struct ast2600_i2c_bus *i2c_bus, u32 sts)
+{
+	int target_rx_len = 0;
+	u32 cmd = 0;
+	u8 value;
+	int i;
+
+	sts &= ~(AST2600_I2CS_SLAVE_PENDING);
+	/* Handle i2c target timeout condition */
+	if (AST2600_I2CS_INACTIVE_TO & sts) {
+		cmd = TARGET_TRIGGER_CMD;
+		cmd |= AST2600_I2CS_RX_DMA_EN;
+		writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_TARGET_MSG_BUF_SIZE),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+		writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+		writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_ISR);
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_STOP, &value);
+		return;
+	}
+
+	sts &= ~(AST2600_I2CS_PKT_DONE | AST2600_I2CS_PKT_ERROR);
+
+	switch (sts) {
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA:
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_WAIT_RX_DMA:
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_REQUESTED, &value);
+		target_rx_len = AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base +
+						      AST2600_I2CS_DMA_LEN_STS));
+		for (i = 0; i < target_rx_len; i++) {
+			i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_RECEIVED,
+					&i2c_bus->target_dma_buf[i]);
+		}
+		writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_TARGET_MSG_BUF_SIZE),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+		cmd = TARGET_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN;
+		break;
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_STOP:
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_STOP, &value);
+		writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_TARGET_MSG_BUF_SIZE),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+		cmd = TARGET_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN;
+		break;
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE_NAK |
+			AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_WAIT_RX_DMA |
+			AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+	case AST2600_I2CS_RX_DONE_NAK | AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+	case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_STOP:
+	case AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+	case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA:
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+		if (sts & AST2600_I2CS_SLAVE_MATCH)
+			i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_REQUESTED, &value);
+
+		target_rx_len = AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base +
+						      AST2600_I2CS_DMA_LEN_STS));
+		for (i = 0; i < target_rx_len; i++) {
+			i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_RECEIVED,
+					&i2c_bus->target_dma_buf[i]);
+		}
+		writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_TARGET_MSG_BUF_SIZE),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+		if (sts & AST2600_I2CS_STOP)
+			i2c_slave_event(i2c_bus->target, I2C_SLAVE_STOP, &value);
+		cmd = TARGET_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN;
+		break;
+
+	/* it is Mw data Mr coming -> it need send tx */
+	case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_TX_DMA:
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_TX_DMA:
+		/* it should be repeat start read */
+		if (sts & AST2600_I2CS_SLAVE_MATCH)
+			i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_REQUESTED, &value);
+
+		target_rx_len = AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base +
+						      AST2600_I2CS_DMA_LEN_STS));
+		for (i = 0; i < target_rx_len; i++) {
+			i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_RECEIVED,
+					&i2c_bus->target_dma_buf[i]);
+		}
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_READ_REQUESTED,
+				&i2c_bus->target_dma_buf[0]);
+		writel(0, i2c_bus->reg_base + AST2600_I2CS_DMA_LEN_STS);
+		writel(AST2600_I2CS_SET_TX_DMA_LEN(1),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+		cmd = TARGET_TRIGGER_CMD | AST2600_I2CS_TX_DMA_EN;
+		break;
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_WAIT_TX_DMA:
+		/* First Start read */
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_READ_REQUESTED,
+				&i2c_bus->target_dma_buf[0]);
+		writel(AST2600_I2CS_SET_TX_DMA_LEN(1),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+		cmd = TARGET_TRIGGER_CMD | AST2600_I2CS_TX_DMA_EN;
+		break;
+	case AST2600_I2CS_WAIT_TX_DMA:
+		/* it should be next start read */
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_READ_PROCESSED,
+				&i2c_bus->target_dma_buf[0]);
+		writel(0, i2c_bus->reg_base + AST2600_I2CS_DMA_LEN_STS);
+		writel(AST2600_I2CS_SET_TX_DMA_LEN(1),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+		cmd = TARGET_TRIGGER_CMD | AST2600_I2CS_TX_DMA_EN;
+		break;
+	case AST2600_I2CS_TX_NAK | AST2600_I2CS_STOP:
+		/* it just tx complete */
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_STOP, &value);
+		writel(0, i2c_bus->reg_base + AST2600_I2CS_DMA_LEN_STS);
+		writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_TARGET_MSG_BUF_SIZE),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+		cmd = TARGET_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN;
+		break;
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE:
+		cmd = 0;
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_REQUESTED, &value);
+		break;
+	case AST2600_I2CS_STOP:
+		cmd = 0;
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_STOP, &value);
+		break;
+	default:
+		dev_dbg(i2c_bus->dev, "unhandled target isr case %x, sts %x\n", sts,
+			readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF));
+		break;
+	}
+
+	if (cmd)
+		writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+	writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_ISR);
+	readl(i2c_bus->reg_base + AST2600_I2CS_ISR);
+}
+
+static void ast2600_i2c_target_packet_buff_irq(struct ast2600_i2c_bus *i2c_bus, u32 sts)
+{
+	int target_rx_len = 0;
+	u32 cmd = 0;
+	u8 value;
+	int i;
+
+	/* due to controller target is common buffer, need force the master stop not issue */
+	if (readl(i2c_bus->reg_base + AST2600_I2CM_CMD_STS) & GENMASK(15, 0)) {
+		writel(0, i2c_bus->reg_base + AST2600_I2CM_CMD_STS);
+		i2c_bus->cmd_err = -EBUSY;
+		writel(0, i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		complete(&i2c_bus->cmd_complete);
+	}
+
+	/* Handle i2c target timeout condition */
+	if (AST2600_I2CS_INACTIVE_TO & sts) {
+		/* Reset timeout counter */
+		u32 ac_timing = readl(i2c_bus->reg_base + AST2600_I2CC_AC_TIMING) &
+				AST2600_I2CC_AC_TIMING_MASK;
+
+		writel(ac_timing, i2c_bus->reg_base + AST2600_I2CC_AC_TIMING);
+		ac_timing |= AST2600_I2CC_TTIMEOUT(i2c_bus->timeout);
+		writel(ac_timing, i2c_bus->reg_base + AST2600_I2CC_AC_TIMING);
+		writel(TARGET_TRIGGER_CMD, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+		writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_ISR);
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_STOP, &value);
+		i2c_bus->target_operate = 0;
+		return;
+	}
+
+	sts &= ~(AST2600_I2CS_PKT_DONE | AST2600_I2CS_PKT_ERROR);
+
+	if (sts & AST2600_I2CS_SLAVE_MATCH)
+		i2c_bus->target_operate = 1;
+
+	switch (sts) {
+	case AST2600_I2CS_SLAVE_PENDING | AST2600_I2CS_WAIT_RX_DMA |
+		 AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+	case AST2600_I2CS_SLAVE_PENDING |
+		 AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+	case AST2600_I2CS_SLAVE_PENDING |
+		 AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_STOP:
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_STOP, &value);
+		fallthrough;
+	case AST2600_I2CS_SLAVE_PENDING |
+		 AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE:
+	case AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE:
+	case AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_SLAVE_MATCH:
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_REQUESTED, &value);
+		cmd = TARGET_TRIGGER_CMD;
+		if (sts & AST2600_I2CS_RX_DONE) {
+			target_rx_len = AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
+							       AST2600_I2CC_BUFF_CTRL));
+			for (i = 0; i < target_rx_len; i++) {
+				value = readb(i2c_bus->buf_base + 0x10 + i);
+				i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_RECEIVED, &value);
+			}
+		}
+		if (readl(i2c_bus->reg_base + AST2600_I2CS_CMD_STS) & AST2600_I2CS_RX_BUFF_EN)
+			cmd = 0;
+		else
+			cmd = TARGET_TRIGGER_CMD | AST2600_I2CS_RX_BUFF_EN;
+
+		writel(AST2600_I2CC_SET_RX_BUF_LEN(i2c_bus->buf_size),
+		       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		break;
+	case AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_RX_DONE:
+		cmd = TARGET_TRIGGER_CMD;
+		target_rx_len = AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
+						       AST2600_I2CC_BUFF_CTRL));
+		for (i = 0; i < target_rx_len; i++) {
+			value = readb(i2c_bus->buf_base + 0x10 + i);
+			i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_RECEIVED, &value);
+		}
+		cmd |= AST2600_I2CS_RX_BUFF_EN;
+		writel(AST2600_I2CC_SET_RX_BUF_LEN(i2c_bus->buf_size),
+		       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		break;
+	case AST2600_I2CS_SLAVE_PENDING | AST2600_I2CS_WAIT_RX_DMA |
+				AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+		cmd = TARGET_TRIGGER_CMD;
+		target_rx_len = AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
+								 AST2600_I2CC_BUFF_CTRL));
+		for (i = 0; i < target_rx_len; i++) {
+			value = readb(i2c_bus->buf_base + 0x10 + i);
+			i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_RECEIVED, &value);
+		}
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_STOP, &value);
+		cmd |= AST2600_I2CS_RX_BUFF_EN;
+		writel(AST2600_I2CC_SET_RX_BUF_LEN(i2c_bus->buf_size),
+		       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		break;
+	case AST2600_I2CS_SLAVE_PENDING | AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+		cmd = TARGET_TRIGGER_CMD;
+		target_rx_len = AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
+								 AST2600_I2CC_BUFF_CTRL));
+		for (i = 0; i < target_rx_len; i++) {
+			value = readb(i2c_bus->buf_base + 0x10 + i);
+			i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_RECEIVED, &value);
+		}
+		/* workaround for avoid next start with len != 0 */
+		writel(BIT(0), i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_STOP, &value);
+		break;
+	case AST2600_I2CS_RX_DONE | AST2600_I2CS_STOP:
+		cmd = TARGET_TRIGGER_CMD;
+		target_rx_len = AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
+								 AST2600_I2CC_BUFF_CTRL));
+		for (i = 0; i < target_rx_len; i++) {
+			value = readb(i2c_bus->buf_base + 0x10 + i);
+			i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_RECEIVED, &value);
+		}
+		/* workaround for avoid next start with len != 0 */
+		writel(BIT(0), i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_STOP, &value);
+		break;
+	case AST2600_I2CS_SLAVE_PENDING | AST2600_I2CS_RX_DONE |
+	     AST2600_I2CS_WAIT_TX_DMA | AST2600_I2CS_STOP:
+		target_rx_len = AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
+								 AST2600_I2CC_BUFF_CTRL));
+		for (i = 0; i < target_rx_len; i++) {
+			value = readb(i2c_bus->buf_base + 0x10 + i);
+			i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_RECEIVED, &value);
+		}
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_STOP, &value);
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_READ_REQUESTED, &value);
+		writeb(value, i2c_bus->buf_base);
+		break;
+	case AST2600_I2CS_WAIT_TX_DMA | AST2600_I2CS_SLAVE_MATCH:
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_READ_REQUESTED, &value);
+		writeb(value, i2c_bus->buf_base);
+		writel(AST2600_I2CC_SET_TX_BUF_LEN(1),
+		       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		cmd = TARGET_TRIGGER_CMD | AST2600_I2CS_TX_BUFF_EN;
+		break;
+	case AST2600_I2CS_SLAVE_PENDING | AST2600_I2CS_STOP |
+	     AST2600_I2CS_TX_NAK | AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE:
+	case AST2600_I2CS_SLAVE_PENDING | AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_STOP |
+	     AST2600_I2CS_TX_NAK | AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE:
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_STOP, &value);
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_REQUESTED, &value);
+		target_rx_len = AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
+						AST2600_I2CC_BUFF_CTRL));
+		for (i = 0; i < target_rx_len; i++) {
+			value = readb(i2c_bus->buf_base + 0x10 + i);
+			i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_RECEIVED, &value);
+		}
+		writel(AST2600_I2CC_SET_RX_BUF_LEN(i2c_bus->buf_size),
+		       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		cmd = TARGET_TRIGGER_CMD | AST2600_I2CS_RX_BUFF_EN;
+		break;
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_WAIT_TX_DMA | AST2600_I2CS_RX_DONE:
+	case AST2600_I2CS_WAIT_TX_DMA | AST2600_I2CS_RX_DONE:
+	case AST2600_I2CS_WAIT_TX_DMA:
+		if (sts & AST2600_I2CS_SLAVE_MATCH)
+			i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_REQUESTED, &value);
+
+		if (sts & AST2600_I2CS_RX_DONE) {
+			target_rx_len = AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base +
+							AST2600_I2CC_BUFF_CTRL));
+			for (i = 0; i < target_rx_len; i++) {
+				value = readb(i2c_bus->buf_base + 0x10 + i);
+				i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_RECEIVED, &value);
+			}
+			i2c_slave_event(i2c_bus->target, I2C_SLAVE_READ_REQUESTED, &value);
+		} else {
+			i2c_slave_event(i2c_bus->target, I2C_SLAVE_READ_PROCESSED, &value);
+		}
+		writeb(value, i2c_bus->buf_base);
+		writel(AST2600_I2CC_SET_TX_BUF_LEN(1),
+		       i2c_bus->reg_base + AST2600_I2CC_BUFF_CTRL);
+		cmd = TARGET_TRIGGER_CMD | AST2600_I2CS_TX_BUFF_EN;
+		break;
+	/* workaround : trigger the cmd twice to fix next state keep 1000000 */
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE:
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_REQUESTED, &value);
+		cmd = TARGET_TRIGGER_CMD | AST2600_I2CS_RX_BUFF_EN;
+		writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+		break;
+
+	case AST2600_I2CS_TX_NAK | AST2600_I2CS_STOP:
+	case AST2600_I2CS_STOP:
+		cmd = TARGET_TRIGGER_CMD;
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_STOP, &value);
+		break;
+	default:
+		dev_dbg(i2c_bus->dev, "unhandled target isr case %x, sts %x\n", sts,
+			readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF));
+		break;
+	}
+
+	if (cmd)
+		writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+	writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_ISR);
+	readl(i2c_bus->reg_base + AST2600_I2CS_ISR);
+
+	if ((sts & AST2600_I2CS_STOP) && !(sts & AST2600_I2CS_SLAVE_PENDING))
+		i2c_bus->target_operate = 0;
+}
+
+static void ast2600_i2c_target_byte_irq(struct ast2600_i2c_bus *i2c_bus, u32 sts)
+{
+	u32 i2c_buff = readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+	u32 cmd = AST2600_I2CS_ACTIVE_ALL;
+	u8 byte_data;
+	u8 value;
+
+	switch (sts) {
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA:
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_REQUESTED, &value);
+		/* first address match is address */
+		byte_data = AST2600_I2CC_GET_RX_BUFF(i2c_buff);
+		break;
+	case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA:
+		byte_data = AST2600_I2CC_GET_RX_BUFF(i2c_buff);
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_RECEIVED, &byte_data);
+		break;
+	case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_TX_DMA:
+		cmd |= AST2600_I2CS_TX_CMD;
+		byte_data = AST2600_I2CC_GET_RX_BUFF(i2c_buff);
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_READ_REQUESTED, &byte_data);
+		writel(byte_data, i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+		break;
+	case AST2600_I2CS_TX_ACK | AST2600_I2CS_WAIT_TX_DMA:
+		cmd |= AST2600_I2CS_TX_CMD;
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_READ_PROCESSED, &byte_data);
+		writel(byte_data, i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF);
+		break;
+	case AST2600_I2CS_STOP:
+	case AST2600_I2CS_STOP | AST2600_I2CS_TX_NAK:
+		i2c_slave_event(i2c_bus->target, I2C_SLAVE_STOP, &value);
+		break;
+	default:
+		dev_dbg(i2c_bus->dev, "unhandled pkt isr %x\n", sts);
+		break;
+	}
+	writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+	writel(sts, i2c_bus->reg_base + AST2600_I2CS_ISR);
+	readl(i2c_bus->reg_base + AST2600_I2CS_ISR);
+}
+
+static int ast2600_i2c_target_irq(struct ast2600_i2c_bus *i2c_bus)
+{
+	u32 ier = readl(i2c_bus->reg_base + AST2600_I2CS_IER);
+	u32 isr = readl(i2c_bus->reg_base + AST2600_I2CS_ISR);
+
+	if (!(isr & ier))
+		return 0;
+
+	/*
+	 * Target interrupt coming after Master package done
+	 * So need handle master first.
+	 */
+	if (readl(i2c_bus->reg_base + AST2600_I2CM_ISR) & AST2600_I2CM_PKT_DONE)
+		return 0;
+
+	isr &= ~(AST2600_I2CS_ADDR_INDICATE_MASK);
+
+	if (AST2600_I2CS_ADDR1_NAK & isr)
+		isr &= ~AST2600_I2CS_ADDR1_NAK;
+
+	if (AST2600_I2CS_ADDR2_NAK & isr)
+		isr &= ~AST2600_I2CS_ADDR2_NAK;
+
+	if (AST2600_I2CS_ADDR3_NAK & isr)
+		isr &= ~AST2600_I2CS_ADDR3_NAK;
+
+	if (AST2600_I2CS_ADDR_MASK & isr)
+		isr &= ~AST2600_I2CS_ADDR_MASK;
+
+	if (AST2600_I2CS_PKT_DONE & isr) {
+		if (i2c_bus->mode == DMA_MODE)
+			ast2600_i2c_target_packet_dma_irq(i2c_bus, isr);
+		else
+			ast2600_i2c_target_packet_buff_irq(i2c_bus, isr);
+	} else {
+		ast2600_i2c_target_byte_irq(i2c_bus, isr);
+	}
+
+	return 1;
+}
+#endif
+
 static int ast2600_i2c_setup_dma_tx(u32 cmd, struct ast2600_i2c_bus *i2c_bus)
 {
 	struct i2c_msg *msg = &i2c_bus->msgs[i2c_bus->msgs_index];
@@ -691,6 +1116,20 @@ static void ast2600_i2c_controller_package_irq(struct ast2600_i2c_bus *i2c_bus,
 		}
 		break;
 	case AST2600_I2CM_RX_DONE:
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+		/*
+		 * Workaround for controller/target package mode enable rx done stuck issue
+		 * When master go for first read (RX_DONE), target mode will also effect
+		 * Then controller will send nack, not operate anymore.
+		 */
+		if (readl(i2c_bus->reg_base + AST2600_I2CS_CMD_STS) & AST2600_I2CS_PKT_MODE_EN) {
+			u32 target_cmd = readl(i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+
+			writel(0, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+			writel(target_cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+		}
+		fallthrough;
+#endif
 	case AST2600_I2CM_RX_DONE | AST2600_I2CM_NORMAL_STOP:
 		/* do next rx */
 		if (i2c_bus->mode == DMA_MODE) {
@@ -800,6 +1239,12 @@ static irqreturn_t ast2600_i2c_bus_irq(int irq, void *dev_id)
 {
 	struct ast2600_i2c_bus *i2c_bus = dev_id;
 
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+	if (readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL) & AST2600_I2CC_SLAVE_EN) {
+		if (ast2600_i2c_target_irq(i2c_bus))
+			return IRQ_HANDLED;
+	}
+#endif
 	return IRQ_RETVAL(ast2600_i2c_controller_irq(i2c_bus));
 }
 
@@ -816,12 +1261,30 @@ static int ast2600_i2c_controller_xfer(struct i2c_adapter *adap, struct i2c_msg
 			return ret;
 	}
 
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+	if (i2c_bus->mode == BUFF_MODE) {
+		if (i2c_bus->target_operate)
+			return -EBUSY;
+		/* disable target isr */
+		writel(0, i2c_bus->reg_base + AST2600_I2CS_IER);
+		if (readl(i2c_bus->reg_base + AST2600_I2CS_ISR) || i2c_bus->target_operate) {
+			writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_IER);
+			return -EBUSY;
+		}
+	}
+#endif
+
 	i2c_bus->cmd_err = 0;
 	i2c_bus->msgs = msgs;
 	i2c_bus->msgs_index = 0;
 	i2c_bus->msgs_count = num;
 	reinit_completion(&i2c_bus->cmd_complete);
 	ret = ast2600_i2c_do_start(i2c_bus);
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+	/* avoid race condication target is wait and master wait 1st target operate */
+	if (i2c_bus->mode == BUFF_MODE)
+		writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_IER);
+#endif
 	if (ret)
 		goto controller_out;
 	timeout = wait_for_completion_timeout(&i2c_bus->cmd_complete, i2c_bus->adap.timeout);
@@ -838,7 +1301,26 @@ static int ast2600_i2c_controller_xfer(struct i2c_adapter *adap, struct i2c_msg
 		    (readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF) &
 		    AST2600_I2CC_BUS_BUSY_STS))
 			ast2600_i2c_recover_bus(i2c_bus);
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+		if (ctrl & AST2600_I2CC_SLAVE_EN) {
+			u32 cmd = TARGET_TRIGGER_CMD;
 
+			if (i2c_bus->mode == DMA_MODE) {
+				cmd |= AST2600_I2CS_RX_DMA_EN;
+				writel(i2c_bus->target_dma_addr,
+				       i2c_bus->reg_base + AST2600_I2CS_RX_DMA);
+				writel(i2c_bus->target_dma_addr,
+				       i2c_bus->reg_base + AST2600_I2CS_TX_DMA);
+				writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_TARGET_MSG_BUF_SIZE),
+				       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+			} else if (i2c_bus->mode == BUFF_MODE) {
+				cmd = TARGET_TRIGGER_CMD;
+			} else {
+				cmd &= ~AST2600_I2CS_PKT_MODE_EN;
+			}
+			writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+		}
+#endif
 		ret = -ETIMEDOUT;
 	} else {
 		ret = i2c_bus->cmd_err;
@@ -887,7 +1369,78 @@ static void ast2600_i2c_init(struct ast2600_i2c_bus *i2c_bus)
 
 	/* Clear Interrupt */
 	writel(GENMASK(27, 0), i2c_bus->reg_base + AST2600_I2CM_ISR);
+
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+	/* for memory buffer initial */
+	if (i2c_bus->mode == DMA_MODE) {
+		i2c_bus->target_dma_buf =
+			dmam_alloc_coherent(i2c_bus->dev, I2C_TARGET_MSG_BUF_SIZE,
+					    &i2c_bus->target_dma_addr, GFP_KERNEL);
+		if (!i2c_bus->target_dma_buf)
+			return;
+	}
+
+	writel(GENMASK(27, 0), i2c_bus->reg_base + AST2600_I2CS_ISR);
+
+	if (i2c_bus->mode == BYTE_MODE)
+		writel(GENMASK(15, 0), i2c_bus->reg_base + AST2600_I2CS_IER);
+	else
+		writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_IER);
+#endif
+}
+
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+static int ast2600_i2c_reg_target(struct i2c_client *client)
+{
+	struct ast2600_i2c_bus *i2c_bus = i2c_get_adapdata(client->adapter);
+	u32 cmd = TARGET_TRIGGER_CMD;
+
+	if (i2c_bus->target)
+		return -EINVAL;
+
+	dev_dbg(i2c_bus->dev, "target addr %x\n", client->addr);
+
+	writel(0, i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL);
+	writel(AST2600_I2CC_SLAVE_EN | readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL),
+	       i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+
+	/* trigger rx buffer */
+	if (i2c_bus->mode == DMA_MODE) {
+		cmd |= AST2600_I2CS_RX_DMA_EN;
+		writel(i2c_bus->target_dma_addr, i2c_bus->reg_base + AST2600_I2CS_RX_DMA);
+		writel(i2c_bus->target_dma_addr, i2c_bus->reg_base + AST2600_I2CS_TX_DMA);
+		writel(AST2600_I2CS_SET_RX_DMA_LEN(I2C_TARGET_MSG_BUF_SIZE),
+		       i2c_bus->reg_base + AST2600_I2CS_DMA_LEN);
+	} else if (i2c_bus->mode == BUFF_MODE) {
+		cmd = TARGET_TRIGGER_CMD;
+	} else {
+		cmd &= ~AST2600_I2CS_PKT_MODE_EN;
+	}
+
+	writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS);
+	i2c_bus->target = client;
+	/* Set target addr. */
+	writel(client->addr | AST2600_I2CS_ADDR1_ENABLE,
+	       i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL);
+
+	return 0;
+}
+
+static int ast2600_i2c_unreg_target(struct i2c_client *client)
+{
+	struct ast2600_i2c_bus *i2c_bus = i2c_get_adapdata(client->adapter);
+
+	/* Turn off target mode. */
+	writel(~AST2600_I2CC_SLAVE_EN & readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL),
+	       i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL);
+	writel(readl(i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL) & ~AST2600_I2CS_ADDR1_MASK,
+	       i2c_bus->reg_base + AST2600_I2CS_ADDR_CTRL);
+
+	i2c_bus->target = NULL;
+
+	return 0;
 }
+#endif
 
 static u32 ast2600_i2c_functionality(struct i2c_adapter *adap)
 {
@@ -897,6 +1450,10 @@ static u32 ast2600_i2c_functionality(struct i2c_adapter *adap)
 static const struct i2c_algorithm i2c_ast2600_algorithm = {
 	.xfer = ast2600_i2c_controller_xfer,
 	.functionality = ast2600_i2c_functionality,
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+	.reg_target = ast2600_i2c_reg_target,
+	.unreg_target = ast2600_i2c_unreg_target,
+#endif
 };
 
 int ast2600_i2c_probe(const struct of_device_id *match, struct platform_device *pdev)
@@ -932,6 +1489,9 @@ int ast2600_i2c_probe(const struct of_device_id *match, struct platform_device *
 		regmap_write(i2c_bus->global_regs, AST2600_I2CG_CLK_DIV_CTRL, I2CCG_DIV_CTRL);
 	}
 
+#if IS_ENABLED(CONFIG_I2C_SLAVE)
+	i2c_bus->target_operate = 0;
+#endif
 	i2c_bus->dev = dev;
 	i2c_bus->mode = BUFF_MODE;
 	if (!device_property_read_string(dev, "aspeed,transfer-mode", &xfer_mode)) {
-- 
2.34.1


^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH v22 1/4] dt-bindings: i2c: Split AST2600 binding into a new YAML
  2025-11-12  8:56 ` [PATCH v22 1/4] dt-bindings: i2c: Split AST2600 binding into a new YAML Ryan Chen
@ 2025-11-13  8:00   ` Krzysztof Kozlowski
  0 siblings, 0 replies; 6+ messages in thread
From: Krzysztof Kozlowski @ 2025-11-13  8:00 UTC (permalink / raw)
  To: Ryan Chen
  Cc: bmc-sw, benh, joel, andi.shyti, jk, robh, krzk+dt, conor+dt,
	andrew, p.zabel, andriy.shevchenko, naresh.solanki, linux-i2c,
	openbmc, devicetree, linux-arm-kernel, linux-aspeed, linux-kernel

On Wed, Nov 12, 2025 at 04:56:46PM +0800, Ryan Chen wrote:
> The AST2600 I2C controller introduces a completely new register
> map and Separate control/target register sets, unlike the mixed
> layout used in AST2400/AST2500.
> 
> In addition, at new AST2600 configuration registers and transfer
> modes require new DT properties, which are incompatible with
> existing bindings. Therefore, this creates a dedicated binding
> file for AST2600 to properly describe these new hardware
> capabilities.
> 
> A subsequent change will modify this new binding to properly
> describe the AST2600 hardware.
> 
> The example section updated to reflect the actual AST2600 SoC
> register layout and interrupt configuration.
> Reference: aspeed-g6.dtsi (lines 885-897)
> 
> -I2C bus and buffeset address offsets
>  - AST2600 I2C controller register base starts from 0x80, and the
>    buffer region is located at 0xc00, as defined in AST2600 SOC
>    register map.
> 
> -Interrupt configuration
>  - AST2600 U2C controller are connected to ARM GIC interrupt
>    controller rather than the legacy internal interrupt controller.
> 
> Signed-off-by: Ryan Chen <ryan_chen@aspeedtech.com>
> ---
>  .../bindings/i2c/aspeed,ast2600-i2c.yaml      | 67 +++++++++++++++++++
>  .../devicetree/bindings/i2c/aspeed,i2c.yaml   |  3 +-
>  2 files changed, 68 insertions(+), 2 deletions(-)
>  create mode 100644 Documentation/devicetree/bindings/i2c/aspeed,ast2600-i2c.yaml
> 
> diff --git a/Documentation/devicetree/bindings/i2c/aspeed,ast2600-i2c.yaml b/Documentation/devicetree/bindings/i2c/aspeed,ast2600-i2c.yaml
> new file mode 100644
> index 000000000000..e6ed84c53639
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/i2c/aspeed,ast2600-i2c.yaml
> @@ -0,0 +1,67 @@
> +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> +%YAML 1.2
> +---
> +$id: http://devicetree.org/schemas/i2c/aspeed,ast2600-i2c.yaml#
> +$schema: http://devicetree.org/meta-schemas/core.yaml#
> +
> +title: ASPEED I2C on the AST26XX SoCs
> +
> +maintainers:
> +  - Ryan Chen <ryan_chen@aspeedtech.com>
> +
> +allOf:
> +  - $ref: /schemas/i2c/i2c-controller.yaml#
> +
> +properties:
> +  compatible:
> +    enum:
> +      - aspeed,ast2600-i2c-bus
> +
> +  reg:
> +    minItems: 1
> +    maxItems: 2
> +    description:
> +      The first region covers the controller registers.
> +      The optional second region covers the controller's buffer space.

1. List the items instead. We discussed this already and this had
correct format in the past and now it is getting to some odd style. Why?

2. How region can be optional? Device either has it or does not have it.
Please explain me how one, same SoC has optional IO address space? I
asked to explain WHY this is flexible.

You never replied.

NAK, we are discussing same over and over again. I am not reviewing the
rest. Go to previous versions and read the feedback again.

Best regards,
Krzysztof


^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2025-11-13  8:00 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2025-11-12  8:56 [PATCH v22 0/4] Add ASPEED AST2600 I2C controller driver Ryan Chen
2025-11-12  8:56 ` [PATCH v22 1/4] dt-bindings: i2c: Split AST2600 binding into a new YAML Ryan Chen
2025-11-13  8:00   ` Krzysztof Kozlowski
2025-11-12  8:56 ` [PATCH v22 2/4] dt-bindings: i2c: ast2600-i2c.yaml: Add global-regs and transfer-mode properties Ryan Chen
2025-11-12  8:56 ` [PATCH v22 3/4] i2c: ast2600: Add controller driver for new register layout Ryan Chen
2025-11-12  8:56 ` [PATCH v22 4/4] i2c: ast2600: Add target mode support Ryan Chen

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