From nobody Thu Apr 16 22:33:12 2026 Received: from TWMBX01.aspeed.com (mail.aspeedtech.com [211.20.114.72]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 1DD4838E104; Wed, 25 Feb 2026 09:24:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=211.20.114.72 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772011494; cv=none; b=CiINCh0Nmh87xZ6x/k0ZDnID1AzIdBsYp02ZZfSTwbtsrkuhdNjlX+wVE6lSPix1laoLVXDB5rZM6yaocFPfZNIsSxwvplL//lWB7W7wzAQUbqLLN8n4jRGc7ESWLrKCYOgS2tmo0WpGD4wQwqCwHqPPoNcBLbt/2UwTp2KMAbA= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772011494; c=relaxed/simple; bh=p3XViIblhW8oJFj6n1Zsl2Rw5WTqZm8nLB8Wh7OmMo4=; h=From:Date:Subject:MIME-Version:Content-Type:Message-ID:References: In-Reply-To:To:CC; b=QxJij6Jdf74ufVjGB+ZNLApjS7G6WWkm7CzIwXiQU17Apiv1eXdoQeeFYxfydzKG36q3p2LZi2UhYwwgFkoObW1dDF8A8XU46l9IC0Kbb7ywWp/ts2z1fwBZVZA+WcnCsiSI+bJI/haHPeW1LQWB7mvdvnvSZfpNH1era+1wYAs= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=aspeedtech.com; spf=pass smtp.mailfrom=aspeedtech.com; arc=none smtp.client-ip=211.20.114.72 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=aspeedtech.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=aspeedtech.com Received: from TWMBX01.aspeed.com (192.168.0.62) by TWMBX01.aspeed.com (192.168.0.62) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1748.10; Wed, 25 Feb 2026 17:19:41 +0800 Received: from [127.0.1.1] (192.168.10.13) by TWMBX01.aspeed.com (192.168.0.62) with Microsoft SMTP Server id 15.2.1748.10 via Frontend Transport; Wed, 25 Feb 2026 17:19:41 +0800 From: Ryan Chen Date: Wed, 25 Feb 2026 17:19:38 +0800 Subject: [PATCH v25 1/4] dt-bindings: i2c: Split AST2600 binding into a new YAML Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-ID: <20260225-upstream_i2c-v25-1-9f4bdd954f3f@aspeedtech.com> References: <20260225-upstream_i2c-v25-0-9f4bdd954f3f@aspeedtech.com> In-Reply-To: <20260225-upstream_i2c-v25-0-9f4bdd954f3f@aspeedtech.com> To: , , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Joel Stanley , Andrew Jeffery , "Benjamin Herrenschmidt" , Rayn Chen , Philipp Zabel CC: , , , , , , Ryan Chen X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1772011180; l=3535; i=ryan_chen@aspeedtech.com; s=20251126; h=from:subject:message-id; bh=p3XViIblhW8oJFj6n1Zsl2Rw5WTqZm8nLB8Wh7OmMo4=; b=yyABtNoyBgfq/HsTN7vuppf+LNLpgedEgEYnXwHJK6eePm47Cj81kCQTATl+KqMsokwQu7jj8 MVAoLhx9BMHBkQ9wcPXnxfrqv0Brepquj6mz57dqq8DLD0Xxfe37L86 X-Developer-Key: i=ryan_chen@aspeedtech.com; a=ed25519; pk=Xe73xY6tcnkuRjjbVAB/oU30KdB3FvG4nuJuILj7ZVc= The AST2600 I2C controller introduces a completely new register layout with separate controller and target register blocks, unlike the mixed register layout used by AST2400/AST2500. To describe this properly, split out the AST2600 I2C binding into its own YAML file. The compatible string remains unchanged. The example section is updated to reflect the actual AST2600 SoC register layout and interrupt configuration (aspeed-g6.dtsi, lines 885-897): - I2C bus and buffer register offsets - AST2600 I2C controller register base starts at 0x80, and the buffer region is located at 0xc00, per the AST2600 SoC register map. - Interrupt configuration - AST2600 I2C controllers are connected to the ARM GIC, not the legacy internal interrupt controller. Signed-off-by: Ryan Chen --- .../bindings/i2c/aspeed,ast2600-i2c.yaml | 62 ++++++++++++++++++= ++++ .../devicetree/bindings/i2c/aspeed,i2c.yaml | 3 +- 2 files changed, 63 insertions(+), 2 deletions(-) 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..077be85137c9 --- /dev/null +++ b/Documentation/devicetree/bindings/i2c/aspeed,ast2600-i2c.yaml @@ -0,0 +1,62 @@ +# 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 + +allOf: + - $ref: /schemas/i2c/i2c-controller.yaml# + +properties: + compatible: + enum: + - aspeed,ast2600-i2c-bus + + reg: + items: + - description: controller registers + - description: controller buffer space + + interrupts: + maxItems: 1 + + clocks: + maxItems: 1 + + 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 + #include + i2c@80 { + #address-cells =3D <1>; + #size-cells =3D <0>; + compatible =3D "aspeed,ast2600-i2c-bus"; + reg =3D <0x80 0x80>, <0xc00 0x20>; + clocks =3D <&syscon ASPEED_CLK_APB>; + resets =3D <&syscon ASPEED_RESET_I2C>; + clock-frequency =3D <100000>; + interrupts =3D ; + }; diff --git a/Documentation/devicetree/bindings/i2c/aspeed,i2c.yaml b/Docume= ntation/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# =20 -title: ASPEED I2C on the AST24XX, AST25XX, and AST26XX SoCs +title: ASPEED I2C on the AST24XX, AST25XX SoCs =20 maintainers: - Rayn Chen @@ -17,7 +17,6 @@ properties: enum: - aspeed,ast2400-i2c-bus - aspeed,ast2500-i2c-bus - - aspeed,ast2600-i2c-bus =20 reg: minItems: 1 --=20 2.34.1 From nobody Thu Apr 16 22:33:12 2026 Received: from TWMBX01.aspeed.com (mail.aspeedtech.com [211.20.114.72]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id A762F38E5D7; Wed, 25 Feb 2026 09:24:54 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=211.20.114.72 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772011496; cv=none; b=SKIc8VH4Md7cskl4jNzSs+Tw/r9VQK6bJ5/Yqh316ZecrztW8ZFJGKEcckaO4gYDCpecGgq8rtDRHm2UN4h8cZ0DjnU05izLhr88oQEqd3iYZr2R1y7LV9BbcIcSlyfEV3n6ZcIBxwilfz5vvWJRO2OTdz31R0G4dpW8Lm6OUfE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772011496; c=relaxed/simple; bh=oX37qsTcUQZ/XyFfLT9VnkE5sPvidHdjowEh6vs+5BE=; h=From:Date:Subject:MIME-Version:Content-Type:Message-ID:References: In-Reply-To:To:CC; b=APpjFl0NFNkHUwLfFs3YifGvDIs7i0UAMhurX/Pe8iGDHP0tA2Ql9njn3qaVMLix2/QxUnPeFNBNpCx0nKzQU9RsQFRuUxVuq0AJiqvxAe6jJdXB8jAFJrHiocc+z4VjPPJKHWunQpAIYNws7k43Yw9fOVQwGc6jp9wGnbij+MQ= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=aspeedtech.com; spf=pass smtp.mailfrom=aspeedtech.com; arc=none smtp.client-ip=211.20.114.72 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=aspeedtech.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=aspeedtech.com Received: from TWMBX01.aspeed.com (192.168.0.62) by TWMBX01.aspeed.com (192.168.0.62) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1748.10; Wed, 25 Feb 2026 17:19:41 +0800 Received: from [127.0.1.1] (192.168.10.13) by TWMBX01.aspeed.com (192.168.0.62) with Microsoft SMTP Server id 15.2.1748.10 via Frontend Transport; Wed, 25 Feb 2026 17:19:41 +0800 From: Ryan Chen Date: Wed, 25 Feb 2026 17:19:39 +0800 Subject: [PATCH v25 2/4] dt-bindings: i2c: ast2600-i2c.yaml: Add global-regs and transfer-mode properties Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-ID: <20260225-upstream_i2c-v25-2-9f4bdd954f3f@aspeedtech.com> References: <20260225-upstream_i2c-v25-0-9f4bdd954f3f@aspeedtech.com> In-Reply-To: <20260225-upstream_i2c-v25-0-9f4bdd954f3f@aspeedtech.com> To: , , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Joel Stanley , Andrew Jeffery , "Benjamin Herrenschmidt" , Rayn Chen , Philipp Zabel CC: , , , , , , Ryan Chen X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1772011180; l=2721; i=ryan_chen@aspeedtech.com; s=20251126; h=from:subject:message-id; bh=oX37qsTcUQZ/XyFfLT9VnkE5sPvidHdjowEh6vs+5BE=; b=QqlvBQCChB3mqPzpYxnPzXFaa4Be4013ejFg7dEOh7fjspFug+AfMSLos4WUMeDHySrX0r48S mrEb9/haromC8gX4n8AtgegaCnyD1KHHhlsUjsaHtaF/bSOUTRPgVcQ X-Developer-Key: i=ryan_chen@aspeedtech.com; a=ed25519; pk=Xe73xY6tcnkuRjjbVAB/oU30KdB3FvG4nuJuILj7ZVc= The AST2600 I2C controller supports three transfer modes (byte, buffer, DMA). Add "aspeed,transfer-mode" so DT can select the preferred transfer method per controller instance. Also add the "aspeed,global-regs" phandle to reference the AST2600 global registers syscon/regmap used by the controller. These properties apply only to the AST2600 binding and are not part of the legacy binding, which uses a mixed controller/target register layout and does not have the split register blocks or these new configuration registers. Legacy DTs remain unchanged. Signed-off-by: Ryan Chen --- .../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 077be85137c9..c45c8ceaf897 100644 --- a/Documentation/devicetree/bindings/i2c/aspeed,ast2600-i2c.yaml +++ b/Documentation/devicetree/bindings/i2c/aspeed,ast2600-i2c.yaml @@ -37,6 +37,33 @@ properties: resets: maxItems: 1 =20 + aspeed,transfer-mode: + description: | + ASPEED ast2600 platform equipped with 16 I2C controllers each i2c co= ntroller + 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 AST260= 0 SoC + provides a single DMA engine shared for 16 I2C controller= s, + so only a limited number of controllers can use DMA simul= taneously. + Therefore, the DTS must explicitly assign which controlle= rs 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 @@ -59,4 +86,6 @@ examples: resets =3D <&syscon ASPEED_RESET_I2C>; clock-frequency =3D <100000>; interrupts =3D ; + aspeed,global-regs =3D <&i2c_global>; + aspeed,transfer-mode =3D "buffer"; }; --=20 2.34.1 From nobody Thu Apr 16 22:33:12 2026 Received: from TWMBX01.aspeed.com (mail.aspeedtech.com [211.20.114.72]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B0C2138E5DD; Wed, 25 Feb 2026 09:20:56 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=211.20.114.72 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772011260; cv=none; b=bNDqyZMDE10qGhwBE8lAcAovfMzFOWJGRv7QC0eoVsm1l79absMHTDRX3GpoGEeTh58/JFwTTdtwINzrfxD2ZsQQBPVncN2lvnmhPyTaFVHcUtS9Z5fW0hHqyQ+sJQcBkKAmSLe524pK8DzARVsY5ZWKjmz012qT89SR5u8EEiQ= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772011260; c=relaxed/simple; bh=qty/AEYmXJtCF7x8JbBGFh7RTNsaqdpSuAK/XpP7qjs=; h=From:Date:Subject:MIME-Version:Content-Type:Message-ID:References: In-Reply-To:To:CC; b=d1sSXRwiyczgm+uJSt+DEE48VnJIzEA+2TUxR/0bggYEHssopXhMecNR5Sgv/9DNoxTuX6M2bxi833KYjD+5q+rIJv/z5Q4zaFXccnW0UvHq5LV0yimjnXcTZ5szprqxvE2l5qLQDt2sXlYQdLQPjxDyQIbxbZjZKOXtV4bWOgc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=aspeedtech.com; spf=pass smtp.mailfrom=aspeedtech.com; arc=none smtp.client-ip=211.20.114.72 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=aspeedtech.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=aspeedtech.com Received: from TWMBX01.aspeed.com (192.168.0.62) by TWMBX01.aspeed.com (192.168.0.62) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.2.1748.10; Wed, 25 Feb 2026 17:19:41 +0800 Received: from [127.0.1.1] (192.168.10.13) by TWMBX01.aspeed.com (192.168.0.62) with Microsoft SMTP Server id 15.2.1748.10 via Frontend Transport; Wed, 25 Feb 2026 17:19:41 +0800 From: Ryan Chen Date: Wed, 25 Feb 2026 17:19:40 +0800 Subject: [PATCH v25 3/4] i2c: ast2600: Add controller driver for AST2600 new register set Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-ID: <20260225-upstream_i2c-v25-3-9f4bdd954f3f@aspeedtech.com> References: <20260225-upstream_i2c-v25-0-9f4bdd954f3f@aspeedtech.com> In-Reply-To: <20260225-upstream_i2c-v25-0-9f4bdd954f3f@aspeedtech.com> To: , , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Joel Stanley , Andrew Jeffery , "Benjamin Herrenschmidt" , Rayn Chen , Philipp Zabel CC: , , , , , , Ryan Chen X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1772011180; l=36641; i=ryan_chen@aspeedtech.com; s=20251126; h=from:subject:message-id; bh=qty/AEYmXJtCF7x8JbBGFh7RTNsaqdpSuAK/XpP7qjs=; b=DJWA1mhqRpr+YBeQ5Pkzirh4ZexI50jKVYfynjpsG2C82U1pHejFC/WkJtuO9oD8tM9boZBFw 6QKLWcCS0LCAoAkol4Nh3UDM3byAaSmG7Ku8uF/PfxExY1aCHOcjpu8 X-Developer-Key: i=ryan_chen@aspeedtech.com; a=ed25519; pk=Xe73xY6tcnkuRjjbVAB/oU30KdB3FvG4nuJuILj7ZVc= The AST2600 introduces a new I2C controller register layout, selectable at runtime via global control registers. Compared to the legacy layout used on AST2400/AST2500, the new layout separates controller (master) and target (slave) registers and adds support for packet-based transfers The new register set extends the hardware capabilities with: - Enhanced clock divider configuration for improved timing precision - tCKHighMin timing control for SCL high pulse width - Dual pool buffer mode (separate Tx/Rx buffers) - Extended DMA support with larger buffer size and alignment handling - Dedicated DMA buffers for controller and target directions - Hardware-assisted bus recovery and timeout mechanisms This patch adds an AST2600-specific I2C controller driver implementing the new register layout, including support for packet-based transfers and byte, buffer and DMA transfer modes. The legacy and new register layouts represent the same AST2600 I2C controller IP and therefore share the existing compatible string: "aspeed,ast2600-i2c-bus" To preserve DT ABI compatibility, driver selection is performed at probe time based on DT contents. In particular, the new binding requires the `aspeed,global-regs` phandle, which is absent from legacy DTBs: - The new driver only probes successfully when `aspeed,global-regs` is present. - The existing i2c-aspeed driver returns -ENODEV for AST2600 nodes that provide `aspeed,global-regs`, allowing the new driver to bind. Signed-off-by: Ryan Chen --- Changes in v25: - Rename AST2600_I2CM_SMBUS_ALT to AST2600_I2CM_SMBUS_ALERT. - Refactor transfer mode handling using setup_tx/setup_rx helpers. - Rework DMA handling to use pre-allocated buffers and reduce mapping overhead in interrupt context. - Fix IRQ status checks to use consistent (sts & value) style. - Move device_property_read_bool() to probe(). - Improve probe error handling. - Handle timeout condition in target_byte_irq(). - Rename "package" to "packet". - Remove target reset when master wait_for_completion_timeout(). --- drivers/i2c/busses/Makefile | 2 +- drivers/i2c/busses/i2c-aspeed.c | 5 + drivers/i2c/busses/i2c-ast2600.c | 988 +++++++++++++++++++++++++++++++++++= ++++ 3 files changed, 994 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/Makefile b/drivers/i2c/busses/Makefile index 547123ab351f..ece201a67d41 100644 --- a/drivers/i2c/busses/Makefile +++ b/drivers/i2c/busses/Makefile @@ -37,7 +37,7 @@ obj-$(CONFIG_I2C_POWERMAC) +=3D i2c-powermac.o obj-$(CONFIG_I2C_ALTERA) +=3D i2c-altera.o obj-$(CONFIG_I2C_AMD_MP2) +=3D i2c-amd-mp2-pci.o i2c-amd-mp2-plat.o obj-$(CONFIG_I2C_AMD_ASF) +=3D i2c-amd-asf-plat.o -obj-$(CONFIG_I2C_ASPEED) +=3D i2c-aspeed.o +obj-$(CONFIG_I2C_ASPEED) +=3D i2c-aspeed.o i2c-ast2600.o obj-$(CONFIG_I2C_AT91) +=3D i2c-at91.o i2c-at91-y :=3D i2c-at91-core.o i2c-at91-master.o i2c-at91-$(CONFIG_I2C_AT91_SLAVE_EXPERIMENTAL) +=3D i2c-at91-slave.o diff --git a/drivers/i2c/busses/i2c-aspeed.c b/drivers/i2c/busses/i2c-aspee= d.c index a26b74c71206..8286fd2cd130 100644 --- a/drivers/i2c/busses/i2c-aspeed.c +++ b/drivers/i2c/busses/i2c-aspeed.c @@ -22,6 +22,7 @@ #include #include #include +#include #include #include =20 @@ -1002,6 +1003,10 @@ static int aspeed_i2c_probe_bus(struct platform_devi= ce *pdev) struct clk *parent_clk; int irq, ret; =20 + if (device_is_compatible(&pdev->dev, "aspeed,ast2600-i2c-bus") && + device_property_present(&pdev->dev, "aspeed,global-regs")) + return -ENODEV; + bus =3D devm_kzalloc(&pdev->dev, sizeof(*bus), GFP_KERNEL); if (!bus) return -ENOMEM; diff --git a/drivers/i2c/busses/i2c-ast2600.c b/drivers/i2c/busses/i2c-ast2= 600.c new file mode 100644 index 000000000000..c3e4abb426e2 --- /dev/null +++ b/drivers/i2c/busses/i2c-ast2600.c @@ -0,0 +1,988 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * ASPEED AST2600 new register set I2C controller driver + * + * Copyright (C) 2026 ASPEED Technology Inc. + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#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)) +#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 +#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)) << 1= 6) | 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_ALERT 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) | B= IT(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)) << 1= 6) | 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)) >> 1= 6) + +/* 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 4096 + +#define AST2600_I2C_DMA_SIZE 4096 + +#define CONTROLLER_TRIGGER_LAST_STOP (AST2600_I2CM_RX_CMD_LAST | AST2600_I= 2CM_STOP_CMD) +#define TARGET_TRIGGER_CMD (AST2600_I2CS_ACTIVE_ALL | AST2600_I2CS_PKT_MOD= E_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_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; + int (*setup_tx)(u32 cmd, struct ast2600_i2c_bus *i2c_bus); + int (*setup_rx)(u32 cmd, struct ast2600_i2c_bus *i2c_bus); +}; + +static void ast2600_i2c_ac_timing_config(struct ast2600_i2c_bus *i2c_bus) +{ + unsigned long base_clk[16]; + int baseclk_idx =3D 0; + int divisor =3D 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 =3D 0; i < ARRAY_SIZE(base_clk); i++) { + if (i =3D=3D 0) + base_clk[i] =3D i2c_bus->apb_clk; + else if (i < 5) + base_clk[i] =3D (i2c_bus->apb_clk * 2) / + (((clk_div_reg >> ((i - 1) * 8)) & GENMASK(7, 0)) + 2); + else + base_clk[i] =3D base_clk[4] >> (i - 4); + + if ((base_clk[i] / i2c_bus->timing_info.bus_freq_hz) <=3D 32) { + baseclk_idx =3D i; + divisor =3D DIV_ROUND_UP(base_clk[i], i2c_bus->timing_info.bus_freq_hz); + break; + } + } + baseclk_idx =3D min(baseclk_idx, 15); + divisor =3D min(divisor, 32); + scl_low =3D min(divisor * 9 / 16 - 1, 15); + scl_high =3D (divisor - scl_low - 2) & GENMASK(3, 0); + data =3D (scl_high - 1) << 20 | scl_high << 16 | scl_low << 12 | baseclk_= idx; + if (i2c_bus->timeout) { + data |=3D AST2600_I2CC_TOUTBASECLK(AST_I2C_TIMEOUT_CLK); + data |=3D AST2600_I2CC_TTIMEOUT(i2c_bus->timeout); + } + + writel(data, i2c_bus->reg_base + AST2600_I2CC_AC_TIMING); +} + +static int ast2600_i2c_recover_bus(struct ast2600_i2c_bus *i2c_bus) +{ + u32 state =3D readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF); + int ret =3D 0; + u32 ctrl; + int r; + + dev_dbg(i2c_bus->dev, "%d-bus recovery bus [%x]\n", i2c_bus->adap.nr, sta= te); + + /* reset controller */ + ctrl =3D readl(i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL); + writel(ctrl & ~AST2600_I2CC_MASTER_EN, i2c_bus->reg_base + AST2600_I2CC_F= UN_CTRL); + writel(ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL); + + reinit_completion(&i2c_bus->cmd_complete); + i2c_bus->cmd_err =3D 0; + + /* Check SDA/SCL status in the status register. */ + state =3D readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF); + if (!(state & AST2600_I2CC_SDA_LINE_STS) && (state & AST2600_I2CC_SCL_LIN= E_STS)) { + writel(AST2600_I2CM_RECOVER_CMD_EN, i2c_bus->reg_base + AST2600_I2CM_CMD= _STS); + r =3D wait_for_completion_timeout(&i2c_bus->cmd_complete, i2c_bus->adap.= timeout); + if (r =3D=3D 0) { + dev_dbg(i2c_bus->dev, "recovery timed out\n"); + return -ETIMEDOUT; + } else if (i2c_bus->cmd_err) { + dev_dbg(i2c_bus->dev, "recovery error\n"); + ret =3D -EPROTO; + } + } + + /* Recovery done */ + state =3D 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 =3D -EPROTO; + } + + return ret; +} + +static int ast2600_i2c_setup_dma_tx(u32 cmd, struct ast2600_i2c_bus *i2c_b= us) +{ + struct i2c_msg *msg =3D &i2c_bus->msgs[i2c_bus->msgs_index]; + int xfer_len =3D msg->len - i2c_bus->controller_xfer_cnt; + + cmd |=3D AST2600_I2CM_PKT_EN; + + if (xfer_len > AST2600_I2C_DMA_SIZE) + xfer_len =3D AST2600_I2C_DMA_SIZE; + else if (i2c_bus->msgs_index + 1 =3D=3D i2c_bus->msgs_count) + cmd |=3D AST2600_I2CM_STOP_CMD; + + if (cmd & AST2600_I2CM_START_CMD) + cmd |=3D AST2600_I2CM_PKT_ADDR(msg->addr); + + if (xfer_len) { + memcpy(i2c_bus->controller_dma_buf, msg->buf, xfer_len); + cmd |=3D 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(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 =3D &i2c_bus->msgs[i2c_bus->msgs_index]; + int xfer_len =3D msg->len - i2c_bus->controller_xfer_cnt; + u32 wbuf_dword; + int i; + + cmd |=3D AST2600_I2CM_PKT_EN; + + if (xfer_len > i2c_bus->buf_size) + xfer_len =3D i2c_bus->buf_size; + else if (i2c_bus->msgs_index + 1 =3D=3D i2c_bus->msgs_count) + cmd |=3D AST2600_I2CM_STOP_CMD; + + if (cmd & AST2600_I2CM_START_CMD) + cmd |=3D AST2600_I2CM_PKT_ADDR(msg->addr); + + if (xfer_len) { + cmd |=3D 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 =3D 0; i < xfer_len; i +=3D 4) { + int xfer_cnt =3D i2c_bus->controller_xfer_cnt + i; + + switch (min(xfer_len - i, 4) % 4) { + case 1: + wbuf_dword =3D msg->buf[xfer_cnt]; + break; + case 2: + wbuf_dword =3D get_unaligned_le16(&msg->buf[xfer_cnt]); + break; + case 3: + wbuf_dword =3D get_unaligned_le24(&msg->buf[xfer_cnt]); + break; + default: + wbuf_dword =3D 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 =3D &i2c_bus->msgs[i2c_bus->msgs_index]; + int xfer_len; + + xfer_len =3D msg->len - i2c_bus->controller_xfer_cnt; + + cmd |=3D AST2600_I2CM_PKT_EN; + + if (cmd & AST2600_I2CM_START_CMD) + cmd |=3D AST2600_I2CM_PKT_ADDR(msg->addr); + + if ((i2c_bus->msgs_index + 1 =3D=3D i2c_bus->msgs_count) && + ((i2c_bus->controller_xfer_cnt + 1) =3D=3D msg->len)) + cmd |=3D AST2600_I2CM_STOP_CMD; + + if (xfer_len) { + cmd |=3D 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_b= us) +{ + struct i2c_msg *msg =3D &i2c_bus->msgs[i2c_bus->msgs_index]; + int xfer_len =3D msg->len - i2c_bus->controller_xfer_cnt; + + cmd |=3D AST2600_I2CM_PKT_EN | AST2600_I2CM_RX_DMA_EN | AST2600_I2CM_RX_C= MD; + + if (msg->flags & I2C_M_RECV_LEN) + xfer_len =3D 1; + else if (xfer_len > AST2600_I2C_DMA_SIZE) + xfer_len =3D AST2600_I2C_DMA_SIZE; + else if (i2c_bus->msgs_index + 1 =3D=3D i2c_bus->msgs_count) + cmd |=3D CONTROLLER_TRIGGER_LAST_STOP; + + writel(AST2600_I2CM_SET_RX_DMA_LEN(xfer_len - 1), i2c_bus->reg_base + AST= 2600_I2CM_DMA_LEN); + + if (cmd & AST2600_I2CM_START_CMD) + cmd |=3D AST2600_I2CM_PKT_ADDR(msg->addr); + + 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 =3D &i2c_bus->msgs[i2c_bus->msgs_index]; + int xfer_len =3D msg->len - i2c_bus->controller_xfer_cnt; + + cmd |=3D AST2600_I2CM_PKT_EN | AST2600_I2CM_RX_BUFF_EN | AST2600_I2CM_RX_= CMD; + + if (cmd & AST2600_I2CM_START_CMD) + cmd |=3D AST2600_I2CM_PKT_ADDR(msg->addr); + + if (msg->flags & I2C_M_RECV_LEN) { + dev_dbg(i2c_bus->dev, "smbus read\n"); + xfer_len =3D 1; + } else if (xfer_len > i2c_bus->buf_size) { + xfer_len =3D i2c_bus->buf_size; + } else if (i2c_bus->msgs_index + 1 =3D=3D i2c_bus->msgs_count) { + cmd |=3D 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 =3D &i2c_bus->msgs[i2c_bus->msgs_index]; + + cmd |=3D AST2600_I2CM_PKT_EN | AST2600_I2CM_RX_CMD; + + if (cmd & AST2600_I2CM_START_CMD) + cmd |=3D 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 =3D=3D i2c_bus->msgs_count) && + ((i2c_bus->controller_xfer_cnt + 1) =3D=3D msg->len)) { + cmd |=3D 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 =3D &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); + + if (!i2c_bus->setup_rx || !i2c_bus->setup_tx) + return -EINVAL; + + i2c_bus->controller_xfer_cnt =3D 0; + i2c_bus->buf_index =3D 0; + + if (msg->flags & I2C_M_RD) + return i2c_bus->setup_rx(AST2600_I2CM_START_CMD, i2c_bus); + + return i2c_bus->setup_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 -ETIMEDOUT; + if (irq_status & (AST2600_I2CM_ABNORMAL)) + return -EPROTO; + + return 0; +} + +static void ast2600_i2c_controller_packet_irq(struct ast2600_i2c_bus *i2c_= bus, u32 sts) +{ + struct i2c_msg *msg =3D &i2c_bus->msgs[i2c_bus->msgs_index]; + int xfer_len; + int i; + + sts &=3D ~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 =3D -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_S= TOP: + i2c_bus->cmd_err =3D -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 =3D -ENOMEM; + complete(&i2c_bus->cmd_complete); + } + } else { + i2c_bus->cmd_err =3D 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 =3D=3D DMA_MODE) + xfer_len =3D AST2600_I2C_GET_TX_DMA_LEN(readl(i2c_bus->reg_base + + AST2600_I2CM_DMA_LEN_STS)); + else if (i2c_bus->mode =3D=3D BUFF_MODE) + xfer_len =3D AST2600_I2CC_GET_TX_BUF_LEN(readl(i2c_bus->reg_base + + AST2600_I2CC_BUFF_CTRL)); + else + xfer_len =3D 1; + + i2c_bus->controller_xfer_cnt +=3D xfer_len; + + if (i2c_bus->controller_xfer_cnt =3D=3D msg->len) { + i2c_bus->msgs_index++; + if (i2c_bus->msgs_index =3D=3D i2c_bus->msgs_count) { + i2c_bus->cmd_err =3D i2c_bus->msgs_index; + complete(&i2c_bus->cmd_complete); + } else { + if (ast2600_i2c_do_start(i2c_bus)) { + i2c_bus->cmd_err =3D -ENOMEM; + complete(&i2c_bus->cmd_complete); + } + } + } else { + i2c_bus->setup_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 =3D=3D DMA_MODE) { + xfer_len =3D AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base + + AST2600_I2CM_DMA_LEN_STS)); + memcpy(&msg->buf[i2c_bus->controller_xfer_cnt], + i2c_bus->controller_dma_buf, xfer_len); + } else if (i2c_bus->mode =3D=3D BUFF_MODE) { + xfer_len =3D AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base + + AST2600_I2CC_BUFF_CTRL)); + for (i =3D 0; i < xfer_len; i++) + msg->buf[i2c_bus->controller_xfer_cnt + i] =3D + readb(i2c_bus->buf_base + 0x10 + i); + } else { + xfer_len =3D 1; + msg->buf[i2c_bus->controller_xfer_cnt] =3D + 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 =3D AST2600_I2CC_GET_RX_BUFF(readl(i2c_bus->reg_base + + AST2600_I2CC_STS_AND_BUFF)); + msg->len =3D min_t(unsigned int, recv_len, I2C_SMBUS_BLOCK_MAX); + msg->len +=3D ((msg->flags & I2C_CLIENT_PEC) ? 2 : 1); + msg->flags &=3D ~I2C_M_RECV_LEN; + if (!recv_len) + i2c_bus->controller_xfer_cnt =3D 0; + else + i2c_bus->controller_xfer_cnt =3D 1; + } else { + i2c_bus->controller_xfer_cnt +=3D xfer_len; + } + + if (i2c_bus->controller_xfer_cnt =3D=3D msg->len) { + i2c_bus->msgs_index++; + if (i2c_bus->msgs_index =3D=3D i2c_bus->msgs_count) { + i2c_bus->cmd_err =3D i2c_bus->msgs_index; + complete(&i2c_bus->cmd_complete); + } else { + if (ast2600_i2c_do_start(i2c_bus)) { + i2c_bus->cmd_err =3D -ENOMEM; + complete(&i2c_bus->cmd_complete); + } + } + } else { + i2c_bus->setup_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 =3D readl(i2c_bus->reg_base + AST2600_I2CM_ISR); + u32 ctrl; + + sts &=3D ~AST2600_I2CM_SMBUS_ALERT; + + if (sts & AST2600_I2CM_BUS_RECOVER_FAIL) { + writel(AST2600_I2CM_BUS_RECOVER_FAIL, i2c_bus->reg_base + AST2600_I2CM_I= SR); + ctrl =3D 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 =3D -EPROTO; + complete(&i2c_bus->cmd_complete); + return 1; + } + + if (sts & AST2600_I2CM_BUS_RECOVER) { + writel(AST2600_I2CM_BUS_RECOVER, i2c_bus->reg_base + AST2600_I2CM_ISR); + i2c_bus->cmd_err =3D 0; + complete(&i2c_bus->cmd_complete); + return 1; + } + + i2c_bus->cmd_err =3D 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 (sts & AST2600_I2CM_PKT_DONE) { + ast2600_i2c_controller_packet_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 =3D dev_id; + + return IRQ_RETVAL(ast2600_i2c_controller_irq(i2c_bus)); +} + +static int ast2600_i2c_controller_xfer(struct i2c_adapter *adap, struct i2= c_msg *msgs, int num) +{ + struct ast2600_i2c_bus *i2c_bus =3D 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 =3D ast2600_i2c_recover_bus(i2c_bus); + if (ret) + return ret; + } + + i2c_bus->cmd_err =3D 0; + i2c_bus->msgs =3D msgs; + i2c_bus->msgs_index =3D 0; + i2c_bus->msgs_count =3D num; + reinit_completion(&i2c_bus->cmd_complete); + ret =3D ast2600_i2c_do_start(i2c_bus); + if (ret) + goto controller_out; + timeout =3D wait_for_completion_timeout(&i2c_bus->cmd_complete, i2c_bus->= adap.timeout); + if (timeout =3D=3D 0) { + u32 ctrl =3D 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(ctrl & ~AST2600_I2CC_MASTER_EN, i2c_bus->reg_base + AST2600_I2CC_= FUN_CTRL); + writel(ctrl, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL); + + /* + * A slave holding SCL low can stall the transfer and trigger + * a master timeout. In multi-master mode, attempt bus recovery + * if the bus is still busy. + */ + 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 =3D -ETIMEDOUT; + } else { + ret =3D 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: + return ret; +} + +static int ast2600_i2c_init(struct ast2600_i2c_bus *i2c_bus) +{ + u32 fun_ctrl =3D AST2600_I2CC_BUS_AUTO_RELEASE | AST2600_I2CC_MASTER_EN; + + /* I2C Reset */ + writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL); + + if (!i2c_bus->multi_master) + fun_ctrl |=3D 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 */ + ast2600_i2c_ac_timing_config(i2c_bus); + + if (i2c_bus->mode =3D=3D DMA_MODE) { + i2c_bus->controller_dma_buf =3D + dmam_alloc_coherent(i2c_bus->dev, AST2600_I2C_DMA_SIZE, + &i2c_bus->controller_dma_addr, GFP_KERNEL); + if (!i2c_bus->controller_dma_buf) + return -ENOMEM; + writel(i2c_bus->controller_dma_addr, + i2c_bus->reg_base + AST2600_I2CM_TX_DMA); + writel(i2c_bus->controller_dma_addr, + i2c_bus->reg_base + AST2600_I2CM_RX_DMA); + } + + /* Clear Interrupt */ + writel(GENMASK(27, 0), i2c_bus->reg_base + AST2600_I2CM_ISR); + + return 0; +} + +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 =3D { + .xfer =3D ast2600_i2c_controller_xfer, + .functionality =3D ast2600_i2c_functionality, +}; + +static int ast2600_i2c_probe(struct platform_device *pdev) +{ + struct device *dev =3D &pdev->dev; + struct ast2600_i2c_bus *i2c_bus; + struct reset_control *rst; + const char *xfer_mode; + struct resource *res; + u32 global_ctrl; + int ret; + + if (!device_property_present(dev, "aspeed,global-regs")) + return -ENODEV; + + i2c_bus =3D devm_kzalloc(dev, sizeof(*i2c_bus), GFP_KERNEL); + if (!i2c_bus) + return -ENOMEM; + + i2c_bus->reg_base =3D devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(i2c_bus->reg_base)) + return PTR_ERR(i2c_bus->reg_base); + + rst =3D 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 =3D + 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) !=3D AST2600_GLOBAL_INIT) { + regmap_write(i2c_bus->global_regs, AST2600_I2CG_CTRL, AST2600_GLOBAL_INI= T); + regmap_write(i2c_bus->global_regs, AST2600_I2CG_CLK_DIV_CTRL, I2CCG_DIV_= CTRL); + } + + i2c_bus->dev =3D dev; + i2c_bus->multi_master =3D device_property_read_bool(dev, "multi-master"); + i2c_bus->mode =3D BUFF_MODE; + if (!device_property_read_string(dev, "aspeed,transfer-mode", &xfer_mode)= ) { + if (!strcmp(xfer_mode, "dma")) + i2c_bus->mode =3D DMA_MODE; + else if (!strcmp(xfer_mode, "byte")) + i2c_bus->mode =3D BYTE_MODE; + else + i2c_bus->mode =3D BUFF_MODE; + } + + if (i2c_bus->mode =3D=3D BUFF_MODE) { + i2c_bus->buf_base =3D devm_platform_get_and_ioremap_resource(pdev, 1, &r= es); + if (IS_ERR(i2c_bus->buf_base)) + i2c_bus->mode =3D BYTE_MODE; + else + i2c_bus->buf_size =3D resource_size(res) / 2; + } + + switch (i2c_bus->mode) { + case DMA_MODE: + i2c_bus->setup_tx =3D ast2600_i2c_setup_dma_tx; + i2c_bus->setup_rx =3D ast2600_i2c_setup_dma_rx; + break; + case BUFF_MODE: + default: + i2c_bus->setup_tx =3D ast2600_i2c_setup_buff_tx; + i2c_bus->setup_rx =3D ast2600_i2c_setup_buff_rx; + break; + case BYTE_MODE: + i2c_bus->setup_tx =3D ast2600_i2c_setup_byte_tx; + i2c_bus->setup_rx =3D ast2600_i2c_setup_byte_rx; + break; + } + + /* + * i2c timeout counter: use base clk4 1Mhz, + * per unit: 1/(1000/1024) =3D 1024us + */ + ret =3D device_property_read_u32(dev, "i2c-scl-clk-low-timeout-us", &i2c_= bus->timeout); + if (!ret) + i2c_bus->timeout =3D DIV_ROUND_UP(i2c_bus->timeout, 1024); + + init_completion(&i2c_bus->cmd_complete); + + i2c_bus->irq =3D platform_get_irq(pdev, 0); + if (i2c_bus->irq < 0) + return i2c_bus->irq; + + platform_set_drvdata(pdev, i2c_bus); + + i2c_bus->clk =3D 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 clo= ck\n"); + + i2c_bus->apb_clk =3D 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 =3D THIS_MODULE; + i2c_bus->adap.algo =3D &i2c_ast2600_algorithm; + i2c_bus->adap.retries =3D 0; + i2c_bus->adap.dev.parent =3D i2c_bus->dev; + device_set_node(&i2c_bus->adap.dev, dev_fwnode(dev)); + i2c_bus->adap.algo_data =3D i2c_bus; + strscpy(i2c_bus->adap.name, pdev->name); + i2c_set_adapdata(&i2c_bus->adap, i2c_bus); + + ret =3D ast2600_i2c_init(i2c_bus); + if (ret < 0) + return dev_err_probe(dev, ret, "Unable to initial i2c %d\n", ret); + + ret =3D devm_request_irq(dev, i2c_bus->irq, ast2600_i2c_bus_irq, 0, + dev_name(dev), i2c_bus); + if (ret < 0) { + ret =3D dev_err_probe(dev, ret, "Unable to request irq %d\n", + i2c_bus->irq); + goto err; + } + + writel(AST2600_I2CM_PKT_DONE | AST2600_I2CM_BUS_RECOVER, + i2c_bus->reg_base + AST2600_I2CM_IER); + + ret =3D devm_i2c_add_adapter(dev, &i2c_bus->adap); + if (ret) + goto err; + + return 0; + +err: + writel(0, i2c_bus->reg_base + AST2600_I2CC_FUN_CTRL); + writel(0, i2c_bus->reg_base + AST2600_I2CM_IER); + return ret; +} + +static void ast2600_i2c_remove(struct platform_device *pdev) +{ + struct ast2600_i2c_bus *i2c_bus =3D 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); +} + +static const struct of_device_id ast2600_i2c_of_match[] =3D { + { .compatible =3D "aspeed,ast2600-i2c-bus" }, + { } +}; +MODULE_DEVICE_TABLE(of, ast2600_i2c_of_match); + +static struct platform_driver ast2600_i2c_driver =3D { + .probe =3D ast2600_i2c_probe, + .remove =3D ast2600_i2c_remove, + .driver =3D { + .name =3D "ast2600-i2c", + .of_match_table =3D ast2600_i2c_of_match, + }, +}; +module_platform_driver(ast2600_i2c_driver); + +MODULE_AUTHOR("Ryan Chen "); +MODULE_DESCRIPTION("ASPEED AST2600 I2C Controller Driver"); +MODULE_LICENSE("GPL"); --=20 2.34.1 From nobody Thu Apr 16 22:33:12 2026 Received: from TWMBX01.aspeed.com (mail.aspeedtech.com [211.20.114.72]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8C3032C0263; Wed, 25 Feb 2026 09:20:53 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=211.20.114.72 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772011256; cv=none; b=H5iScnlDR59jHcULjBpfp8x0WpXiaW/M4nJ56Kck82syGiZw1ixCt8dSJDkPDkZ3ULD+ikJUjPy9Tnal0Ln+TDY5rxO9RWq4TSiTeRKVy/AnIuEDQRT61Jw4BInagLNw0KKKqVcYuyY2yfUSgykk8VUNFaJAd0lO5Ej51RLR7qo= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772011256; c=relaxed/simple; bh=deYbWCQ84iHM9aE9nxhlxi14pN/53DFt4HKGu85rb1k=; 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Wed, 25 Feb 2026 17:19:41 +0800 From: Ryan Chen Date: Wed, 25 Feb 2026 17:19:41 +0800 Subject: [PATCH v25 4/4] i2c: ast2600: Add target mode support Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Message-ID: <20260225-upstream_i2c-v25-4-9f4bdd954f3f@aspeedtech.com> References: <20260225-upstream_i2c-v25-0-9f4bdd954f3f@aspeedtech.com> In-Reply-To: <20260225-upstream_i2c-v25-0-9f4bdd954f3f@aspeedtech.com> To: , , Andi Shyti , Rob Herring , Krzysztof Kozlowski , Conor Dooley , Joel Stanley , Andrew Jeffery , "Benjamin Herrenschmidt" , Rayn Chen , Philipp Zabel CC: , , , , , , Ryan Chen X-Mailer: b4 0.14.3 X-Developer-Signature: v=1; a=ed25519-sha256; t=1772011180; l=25832; i=ryan_chen@aspeedtech.com; s=20251126; h=from:subject:message-id; bh=deYbWCQ84iHM9aE9nxhlxi14pN/53DFt4HKGu85rb1k=; b=G6r5Uh08WdMxCnb2lddPvTgMtuAz6L6ZGkWl9Dtvgd/S/9L7K+n6CNs7FY4voHuv41WpIrQdv f5qY0CFkTcrA1jyhd1pIqG8gY58bhr8zjg8Bivhb78+zXBwNBN7Ys9C X-Developer-Key: i=ryan_chen@aspeedtech.com; a=ed25519; pk=Xe73xY6tcnkuRjjbVAB/oU30KdB3FvG4nuJuILj7ZVc= Add target mode support to the AST2600 I2C driver. 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 --- drivers/i2c/busses/i2c-ast2600.c | 559 +++++++++++++++++++++++++++++++++++= +++- 1 file changed, 558 insertions(+), 1 deletion(-) diff --git a/drivers/i2c/busses/i2c-ast2600.c b/drivers/i2c/busses/i2c-ast2= 600.c index c3e4abb426e2..861a1d2df310 100644 --- a/drivers/i2c/busses/i2c-ast2600.c +++ b/drivers/i2c/busses/i2c-ast2600.c @@ -273,6 +273,13 @@ struct ast2600_i2c_bus { void __iomem *buf_base; int (*setup_tx)(u32 cmd, struct ast2600_i2c_bus *i2c_bus); int (*setup_rx)(u32 cmd, struct ast2600_i2c_bus *i2c_bus); +#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 }; =20 static void ast2600_i2c_ac_timing_config(struct ast2600_i2c_bus *i2c_bus) @@ -356,6 +363,440 @@ static int ast2600_i2c_recover_bus(struct ast2600_i2c= _bus *i2c_bus) return ret; } =20 +#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 =3D 0; + u32 cmd =3D 0; + u8 value; + int i; + + sts &=3D ~(AST2600_I2CS_SLAVE_PENDING); + /* Handle i2c target timeout condition */ + if (sts & AST2600_I2CS_INACTIVE_TO) { + /* Reset timeout counter */ + u32 ac_timing =3D 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 |=3D AST2600_I2CC_TTIMEOUT(i2c_bus->timeout); + writel(ac_timing, i2c_bus->reg_base + AST2600_I2CC_AC_TIMING); + cmd =3D TARGET_TRIGGER_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 &=3D ~(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 =3D AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base + + AST2600_I2CS_DMA_LEN_STS)); + for (i =3D 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 =3D 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 =3D 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 =3D AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base + + AST2600_I2CS_DMA_LEN_STS)); + for (i =3D 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 =3D 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 =3D AST2600_I2C_GET_RX_DMA_LEN(readl(i2c_bus->reg_base + + AST2600_I2CS_DMA_LEN_STS)); + for (i =3D 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(AST2600_I2CS_SET_TX_DMA_LEN(1), + i2c_bus->reg_base + AST2600_I2CS_DMA_LEN); + cmd =3D 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 =3D 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(AST2600_I2CS_SET_TX_DMA_LEN(1), + i2c_bus->reg_base + AST2600_I2CS_DMA_LEN); + cmd =3D 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(AST2600_I2CS_SET_RX_DMA_LEN(I2C_TARGET_MSG_BUF_SIZE), + i2c_bus->reg_base + AST2600_I2CS_DMA_LEN); + cmd =3D TARGET_TRIGGER_CMD | AST2600_I2CS_RX_DMA_EN; + break; + case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DONE: + i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_REQUESTED, &value); + break; + case AST2600_I2CS_STOP: + 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 =3D 0; + u32 cmd =3D 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 =3D -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 =3D 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 |=3D 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 =3D 0; + return; + } + + sts &=3D ~(AST2600_I2CS_PKT_DONE | AST2600_I2CS_PKT_ERROR); + + if (sts & AST2600_I2CS_SLAVE_MATCH) + i2c_bus->target_operate =3D 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_D= ONE: + case AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_R= X_DONE: + case AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS_SLAVE_MATCH: + i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_REQUESTED, &value); + cmd =3D TARGET_TRIGGER_CMD; + if (sts & AST2600_I2CS_RX_DONE) { + target_rx_len =3D AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base + + AST2600_I2CC_BUFF_CTRL)); + for (i =3D 0; i < target_rx_len; i++) { + value =3D 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_BU= FF_EN) + cmd =3D 0; + else + cmd =3D 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 =3D TARGET_TRIGGER_CMD; + target_rx_len =3D AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base + + AST2600_I2CC_BUFF_CTRL)); + for (i =3D 0; i < target_rx_len; i++) { + value =3D readb(i2c_bus->buf_base + 0x10 + i); + i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_RECEIVED, &value); + } + cmd |=3D 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 =3D TARGET_TRIGGER_CMD; + target_rx_len =3D AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base + + AST2600_I2CC_BUFF_CTRL)); + for (i =3D 0; i < target_rx_len; i++) { + value =3D 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 |=3D 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_STO= P: + cmd =3D TARGET_TRIGGER_CMD; + target_rx_len =3D AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base + + AST2600_I2CC_BUFF_CTRL)); + for (i =3D 0; i < target_rx_len; i++) { + value =3D 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 !=3D 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 =3D TARGET_TRIGGER_CMD; + target_rx_len =3D AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base + + AST2600_I2CC_BUFF_CTRL)); + for (i =3D 0; i < target_rx_len; i++) { + value =3D 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 !=3D 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 =3D AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base + + AST2600_I2CC_BUFF_CTRL)); + for (i =3D 0; i < target_rx_len; i++) { + value =3D 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 =3D 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_DON= E: + case AST2600_I2CS_SLAVE_PENDING | AST2600_I2CS_WAIT_RX_DMA | AST2600_I2CS= _STOP | + AST2600_I2CS_TX_NAK | AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_RX_DON= E: + i2c_slave_event(i2c_bus->target, I2C_SLAVE_STOP, &value); + i2c_slave_event(i2c_bus->target, I2C_SLAVE_WRITE_REQUESTED, &value); + target_rx_len =3D AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base + + AST2600_I2CC_BUFF_CTRL)); + for (i =3D 0; i < target_rx_len; i++) { + value =3D 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 =3D TARGET_TRIGGER_CMD | AST2600_I2CS_RX_BUFF_EN; + break; + case AST2600_I2CS_SLAVE_MATCH | AST2600_I2CS_WAIT_TX_DMA | AST2600_I2CS_R= X_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 =3D AST2600_I2CC_GET_RX_BUF_LEN(readl(i2c_bus->reg_base + + AST2600_I2CC_BUFF_CTRL)); + for (i =3D 0; i < target_rx_len; i++) { + value =3D 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 =3D 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 =3D 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 =3D 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 =3D 0; +} + +static void ast2600_i2c_target_byte_irq(struct ast2600_i2c_bus *i2c_bus, u= 32 sts) +{ + u32 i2c_buff =3D readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF); + u32 cmd =3D AST2600_I2CS_ACTIVE_ALL; + u8 byte_data; + u8 value; + + /* Handle i2c target timeout condition */ + if (sts & AST2600_I2CS_INACTIVE_TO) { + /* Reset timeout counter */ + u32 ac_timing =3D 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 |=3D AST2600_I2CC_TTIMEOUT(i2c_bus->timeout); + writel(ac_timing, i2c_bus->reg_base + AST2600_I2CC_AC_TIMING); + writel(AST2600_I2CS_ACTIVE_ALL, 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); + i2c_slave_event(i2c_bus->target, I2C_SLAVE_STOP, &value); + i2c_bus->target_operate =3D 0; + return; + } + + 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 =3D AST2600_I2CC_GET_RX_BUFF(i2c_buff); + break; + case AST2600_I2CS_RX_DONE | AST2600_I2CS_WAIT_RX_DMA: + byte_data =3D 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 |=3D AST2600_I2CS_TX_CMD; + byte_data =3D 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 |=3D 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 =3D readl(i2c_bus->reg_base + AST2600_I2CS_IER); + u32 isr =3D readl(i2c_bus->reg_base + AST2600_I2CS_ISR); + + if (!(isr & ier)) + return 0; + + /* + * Target interrupt coming after controller packet done + * So need handle controller first. + */ + if (readl(i2c_bus->reg_base + AST2600_I2CM_ISR) & AST2600_I2CM_PKT_DONE) + return 0; + + isr &=3D ~(AST2600_I2CS_ADDR_INDICATE_MASK); + + if (AST2600_I2CS_ADDR1_NAK & isr) + isr &=3D ~AST2600_I2CS_ADDR1_NAK; + + if (AST2600_I2CS_ADDR2_NAK & isr) + isr &=3D ~AST2600_I2CS_ADDR2_NAK; + + if (AST2600_I2CS_ADDR3_NAK & isr) + isr &=3D ~AST2600_I2CS_ADDR3_NAK; + + if (AST2600_I2CS_ADDR_MASK & isr) + isr &=3D ~AST2600_I2CS_ADDR_MASK; + + if (AST2600_I2CS_PKT_DONE & isr) { + if (i2c_bus->mode =3D=3D 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_b= us) { struct i2c_msg *msg =3D &i2c_bus->msgs[i2c_bus->msgs_index]; @@ -627,6 +1068,20 @@ static void ast2600_i2c_controller_packet_irq(struct = ast2600_i2c_bus *i2c_bus, u } break; case AST2600_I2CM_RX_DONE: +#if IS_ENABLED(CONFIG_I2C_SLAVE) + /* + * Workaround for controller/target packet mode enable rx done stuck iss= ue + * When controller go for first read (RX_DONE), target mode will also ef= fect + * Then controller will send nack, not operate anymore. + */ + if (readl(i2c_bus->reg_base + AST2600_I2CS_CMD_STS) & AST2600_I2CS_PKT_M= ODE_EN) { + u32 target_cmd =3D 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 =3D=3D DMA_MODE) { @@ -725,6 +1180,12 @@ static irqreturn_t ast2600_i2c_bus_irq(int irq, void = *dev_id) { struct ast2600_i2c_bus *i2c_bus =3D dev_id; =20 +#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)); } =20 @@ -741,12 +1202,30 @@ static int ast2600_i2c_controller_xfer(struct i2c_ad= apter *adap, struct i2c_msg return ret; } =20 +#if IS_ENABLED(CONFIG_I2C_SLAVE) + if (i2c_bus->mode =3D=3D 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_opera= te) { + writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_IER); + return -EBUSY; + } + } +#endif + i2c_bus->cmd_err =3D 0; i2c_bus->msgs =3D msgs; i2c_bus->msgs_index =3D 0; i2c_bus->msgs_count =3D num; reinit_completion(&i2c_bus->cmd_complete); ret =3D ast2600_i2c_do_start(i2c_bus); +#if IS_ENABLED(CONFIG_I2C_SLAVE) + /* avoid race condication target is wait and controller wait 1st target o= perate */ + if (i2c_bus->mode =3D=3D BUFF_MODE) + writel(AST2600_I2CS_PKT_DONE, i2c_bus->reg_base + AST2600_I2CS_IER); +#endif if (ret) goto controller_out; timeout =3D wait_for_completion_timeout(&i2c_bus->cmd_complete, i2c_bus->= adap.timeout); @@ -764,7 +1243,7 @@ static int ast2600_i2c_controller_xfer(struct i2c_adap= ter *adap, struct i2c_msg * a master timeout. In multi-master mode, attempt bus recovery * if the bus is still busy. */ - if (i2c_bus->multi_master && + if (i2c_bus->multi_master && !i2c_bus->target_operate && (readl(i2c_bus->reg_base + AST2600_I2CC_STS_AND_BUFF) & AST2600_I2CC_BUS_BUSY_STS)) ast2600_i2c_recover_bus(i2c_bus); @@ -812,8 +1291,79 @@ static int ast2600_i2c_init(struct ast2600_i2c_bus *i= 2c_bus) /* Clear Interrupt */ writel(GENMASK(27, 0), i2c_bus->reg_base + AST2600_I2CM_ISR); =20 +#if IS_ENABLED(CONFIG_I2C_SLAVE) + /* for memory buffer initial */ + if (i2c_bus->mode =3D=3D DMA_MODE) { + i2c_bus->target_dma_buf =3D + 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 -ENOMEM; + } + + writel(GENMASK(27, 0), i2c_bus->reg_base + AST2600_I2CS_ISR); + + if (i2c_bus->mode =3D=3D 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 + + return 0; +} + +#if IS_ENABLED(CONFIG_I2C_SLAVE) +static int ast2600_i2c_reg_target(struct i2c_client *client) +{ + struct ast2600_i2c_bus *i2c_bus =3D i2c_get_adapdata(client->adapter); + u32 cmd =3D 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 =3D=3D DMA_MODE) { + cmd |=3D 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 =3D=3D BUFF_MODE) { + cmd =3D TARGET_TRIGGER_CMD; + } else { + cmd &=3D ~AST2600_I2CS_PKT_MODE_EN; + } + + writel(cmd, i2c_bus->reg_base + AST2600_I2CS_CMD_STS); + i2c_bus->target =3D 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 =3D i2c_get_adapdata(client->adapter); + + /* Turn off target mode. */ + writel(~AST2600_I2CC_SLAVE_EN & readl(i2c_bus->reg_base + AST2600_I2CC_FU= N_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 =3D NULL; + return 0; } +#endif =20 static u32 ast2600_i2c_functionality(struct i2c_adapter *adap) { @@ -823,6 +1373,10 @@ static u32 ast2600_i2c_functionality(struct i2c_adapt= er *adap) static const struct i2c_algorithm i2c_ast2600_algorithm =3D { .xfer =3D ast2600_i2c_controller_xfer, .functionality =3D ast2600_i2c_functionality, +#if IS_ENABLED(CONFIG_I2C_SLAVE) + .reg_target =3D ast2600_i2c_reg_target, + .unreg_target =3D ast2600_i2c_unreg_target, +#endif }; =20 static int ast2600_i2c_probe(struct platform_device *pdev) @@ -861,6 +1415,9 @@ static int ast2600_i2c_probe(struct platform_device *p= dev) regmap_write(i2c_bus->global_regs, AST2600_I2CG_CLK_DIV_CTRL, I2CCG_DIV_= CTRL); } =20 +#if IS_ENABLED(CONFIG_I2C_SLAVE) + i2c_bus->target_operate =3D 0; +#endif i2c_bus->dev =3D dev; i2c_bus->multi_master =3D device_property_read_bool(dev, "multi-master"); i2c_bus->mode =3D BUFF_MODE; --=20 2.34.1