[PATCH 0/6] i2c: exynos5: Add support for modern Exynos SoCs

@@ -1,53 +0,0 @@
-* Samsung's High Speed I2C controller
-
-The Samsung's High Speed I2C controller is used to interface with I2C devices
-at various speeds ranging from 100khz to 3.4Mhz.
-
-Required properties:
-  - compatible: value should be.
-	-> "samsung,exynos5-hsi2c", (DEPRECATED)
-				for i2c compatible with HSI2C available
-				on Exynos5250 and Exynos5420 SoCs.
-	-> "samsung,exynos5250-hsi2c", for i2c compatible with HSI2C available
-				on Exynos5250 and Exynos5420 SoCs.
-	-> "samsung,exynos5260-hsi2c", for i2c compatible with HSI2C available
-				on Exynos5260 SoCs.
-	-> "samsung,exynos7-hsi2c", for i2c compatible with HSI2C available
-				on Exynos7 SoCs.
-
-  - reg: physical base address of the controller and length of memory mapped
-    region.
-  - interrupts: interrupt number to the cpu.
-  - #address-cells: always 1 (for i2c addresses)
-  - #size-cells: always 0
-
-  - Pinctrl:
-    - pinctrl-0: Pin control group to be used for this controller.
-    - pinctrl-names: Should contain only one value - "default".
-
-Optional properties:
-  - clock-frequency: Desired operating frequency in Hz of the bus.
-    -> If not specified, the bus operates in fast-speed mode at
-       at 100khz.
-    -> If specified, the bus operates in high-speed mode only if the
-       clock-frequency is >= 1Mhz.
-
-Example:
-
-hsi2c@12ca0000 {
-	compatible = "samsung,exynos5250-hsi2c";
-	reg = <0x12ca0000 0x100>;
-	interrupts = <56>;
-	clock-frequency = <100000>;
-
-	pinctrl-0 = <&i2c4_bus>;
-	pinctrl-names = "default";
-
-	#address-cells = <1>;
-	#size-cells = <0>;
-
-	s2mps11_pmic@66 {
-		compatible = "samsung,s2mps11-pmic";
-		reg = <0x66>;
-	};
-};

@@ -0,0 +1,80 @@
+# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
+%YAML 1.2
+---
+$id: http://devicetree.org/schemas/i2c/i2c-exynos5.yaml#
+$schema: http://devicetree.org/meta-schemas/core.yaml#
+
+title: Samsung's High Speed I2C controller
+
+maintainers:
+  - Krzysztof Kozlowski <krzysztof.kozlowski@canonical.com>
+
+description: |
+  The Samsung's High Speed I2C controller is used to interface with I2C devices
+  at various speeds ranging from 100kHz to 3.4MHz.
+
+allOf:
+  - $ref: /schemas/i2c/i2c-controller.yaml#
+
+properties:
+  compatible:
+    oneOf:
+      - enum:
+          - "samsung,exynos5250-hsi2c"    # Exynos5250 and Exynos5420
+          - "samsung,exynos5260-hsi2c"    # Exynos5260
+          - "samsung,exynos7-hsi2c"       # Exynos7
+      - const: "samsung,exynos5-hsi2c"    # Exynos5250 and Exynos5420
+        deprecated: true
+
+  reg:
+    maxItems: 1
+
+  interrupts:
+    maxItems: 1
+
+  clock-frequency:
+    default: 100000
+    description:
+      Desired operating frequency in Hz of the bus.
+
+      If not specified, the bus operates in fast-speed mode at 100kHz.
+
+      If specified, the bus operates in high-speed mode only if the
+      clock-frequency is >= 1MHz.
+
+  clocks:
+    maxItems: 1
+    description: I2C operating clock
+
+  clock-names:
+    const: hsi2c
+
+required:
+  - compatible
+  - reg
+  - interrupts
+  - clocks
+
+unevaluatedProperties: false
+
+examples:
+  - |
+    #include <dt-bindings/clock/exynos5420.h>
+    #include <dt-bindings/interrupt-controller/arm-gic.h>
+    #include <dt-bindings/interrupt-controller/irq.h>
+
+    hsi2c_8: i2c@12e00000 {
+        compatible = "samsung,exynos5250-hsi2c";
+        reg = <0x12e00000 0x1000>;
+        interrupts = <GIC_SPI 87 IRQ_TYPE_LEVEL_HIGH>;
+        #address-cells = <1>;
+        #size-cells = <0>;
+        clock-frequency = <100000>;
+        clocks = <&clock CLK_USI4>;
+        clock-names = "hsi2c";
+
+        pmic@66 {
+            /* compatible = "samsung,s2mps11-pmic"; */
+            reg = <0x66>;
+        };
+    };

@@ -13,6 +13,11 @@ description: |
   The Samsung's High Speed I2C controller is used to interface with I2C devices
   at various speeds ranging from 100kHz to 3.4MHz.
 
+  In case the HSI2C controller is encapsulated within USI block (it's the case
+  e.g. for Exynos850 and Exynos Auto V9 SoCs), it might be also necessary to
+  define USI node in device tree file, choosing "i2c" configuration. Please see
+  Documentation/devicetree/bindings/soc/samsung/exynos-usi.yaml for details.
+
 allOf:
   - $ref: /schemas/i2c/i2c-controller.yaml#
 

@@ -23,6 +28,7 @@ properties:
           - "samsung,exynos5250-hsi2c"    # Exynos5250 and Exynos5420
           - "samsung,exynos5260-hsi2c"    # Exynos5260
           - "samsung,exynos7-hsi2c"       # Exynos7
+          - "samsung,exynosautov9-hsi2c"  # ExynosAutoV9
       - const: "samsung,exynos5-hsi2c"    # Exynos5250 and Exynos5420
         deprecated: true
 

@@ -49,11 +49,16 @@ properties:
       clock-frequency is >= 1MHz.
 
   clocks:
-    maxItems: 1
-    description: I2C operating clock
+    minItems: 1
+    items:
+      - description: I2C operating clock
+      - description: Bus clock (APB)
 
   clock-names:
-    const: hsi2c
+    minItems: 1
+    items:
+      - const: hsi2c
+      - const: hsi2c_pclk
 
 required:
   - compatible

@@ -169,6 +169,7 @@
 enum i2c_type_exynos {
 	I2C_TYPE_EXYNOS5,
 	I2C_TYPE_EXYNOS7,
+	I2C_TYPE_EXYNOSAUTOV9,
 };
 
 struct exynos5_i2c {

@@ -230,6 +231,11 @@ static const struct exynos_hsi2c_variant exynos7_hsi2c_data = {
 	.hw		= I2C_TYPE_EXYNOS7,
 };
 
+static const struct exynos_hsi2c_variant exynosautov9_hsi2c_data = {
+	.fifo_depth	= 64,
+	.hw		= I2C_TYPE_EXYNOSAUTOV9,
+};
+
 static const struct of_device_id exynos5_i2c_match[] = {
 	{
 		.compatible = "samsung,exynos5-hsi2c",

@@ -243,6 +249,9 @@ static const struct of_device_id exynos5_i2c_match[] = {
 	}, {
 		.compatible = "samsung,exynos7-hsi2c",
 		.data = &exynos7_hsi2c_data
+	}, {
+		.compatible = "samsung,exynosautov9-hsi2c",
+		.data = &exynosautov9_hsi2c_data
 	}, {},
 };
 MODULE_DEVICE_TABLE(of, exynos5_i2c_match);

@@ -281,6 +290,31 @@ static int exynos5_i2c_set_timing(struct exynos5_i2c *i2c, bool hs_timings)
 		i2c->op_clock;
 	int div, clk_cycle, temp;
 
+	/*
+	 * In case of HSI2C controllers in ExynosAutoV9:
+	 *
+	 * FSCL = IPCLK / ((CLK_DIV + 1) * 16)
+	 * T_SCL_LOW = IPCLK * (CLK_DIV + 1) * (N + M)
+	 *   [N : number of 0's in the TSCL_H_HS]
+	 *   [M : number of 0's in the TSCL_L_HS]
+	 * T_SCL_HIGH = IPCLK * (CLK_DIV + 1) * (N + M)
+	 *   [N : number of 1's in the TSCL_H_HS]
+	 *   [M : number of 1's in the TSCL_L_HS]
+	 *
+	 * Result of (N + M) is always 8.
+	 * In general case, we don't need to control timing_s1 and timing_s2.
+	 */
+	if (i2c->variant->hw == I2C_TYPE_EXYNOSAUTOV9) {
+		div = ((clkin / (16 * i2c->op_clock)) - 1);
+		i2c_timing_s3 = div << 16;
+		if (hs_timings)
+			writel(i2c_timing_s3, i2c->regs + HSI2C_TIMING_HS3);
+		else
+			writel(i2c_timing_s3, i2c->regs + HSI2C_TIMING_FS3);
+
+		return 0;
+	}
+
 	/*
 	 * In case of HSI2C controller in Exynos5 series
 	 * FPCLK / FI2C =

@@ -422,7 +456,10 @@ static irqreturn_t exynos5_i2c_irq(int irqno, void *dev_id)
 	writel(int_status, i2c->regs + HSI2C_INT_STATUS);
 
 	/* handle interrupt related to the transfer status */
-	if (i2c->variant->hw == I2C_TYPE_EXYNOS7) {
+	switch (i2c->variant->hw) {
+	case I2C_TYPE_EXYNOSAUTOV9:
+		fallthrough;
+	case I2C_TYPE_EXYNOS7:
 		if (int_status & HSI2C_INT_TRANS_DONE) {
 			i2c->trans_done = 1;
 			i2c->state = 0;

@@ -443,7 +480,12 @@ static irqreturn_t exynos5_i2c_irq(int irqno, void *dev_id)
 			i2c->state = -ETIMEDOUT;
 			goto stop;
 		}
-	} else if (int_status & HSI2C_INT_I2C) {
+
+		break;
+	case I2C_TYPE_EXYNOS5:
+		if (!(int_status & HSI2C_INT_I2C))
+			break;
+
 		trans_status = readl(i2c->regs + HSI2C_TRANS_STATUS);
 		if (trans_status & HSI2C_NO_DEV_ACK) {
 			dev_dbg(i2c->dev, "No ACK from device\n");

@@ -465,6 +507,8 @@ static irqreturn_t exynos5_i2c_irq(int irqno, void *dev_id)
 			i2c->trans_done = 1;
 			i2c->state = 0;
 		}
+
+		break;
 	}
 
 	if ((i2c->msg->flags & I2C_M_RD) && (int_status &

@@ -569,13 +613,13 @@ static void exynos5_i2c_bus_check(struct exynos5_i2c *i2c)
 {
 	unsigned long timeout;
 
-	if (i2c->variant->hw != I2C_TYPE_EXYNOS7)
+	if (i2c->variant->hw == I2C_TYPE_EXYNOS5)
 		return;
 
 	/*
-	 * HSI2C_MASTER_ST_LOSE state in EXYNOS7 variant before transaction
-	 * indicates that bus is stuck (SDA is low). In such case bus recovery
-	 * can be performed.
+	 * HSI2C_MASTER_ST_LOSE state (in Exynos7 and ExynosAutoV9 variants)
+	 * before transaction indicates that bus is stuck (SDA is low).
+	 * In such case bus recovery can be performed.
 	 */
 	timeout = jiffies + msecs_to_jiffies(100);
 	for (;;) {

@@ -611,10 +655,10 @@ static void exynos5_i2c_message_start(struct exynos5_i2c *i2c, int stop)
 	unsigned long flags;
 	unsigned short trig_lvl;
 
-	if (i2c->variant->hw == I2C_TYPE_EXYNOS7)
-		int_en |= HSI2C_INT_I2C_TRANS;
-	else
+	if (i2c->variant->hw == I2C_TYPE_EXYNOS5)
 		int_en |= HSI2C_INT_I2C;
+	else
+		int_en |= HSI2C_INT_I2C_TRANS;
 
 	i2c_ctl = readl(i2c->regs + HSI2C_CTL);
 	i2c_ctl &= ~(HSI2C_TXCHON | HSI2C_RXCHON);

@@ -182,7 +182,8 @@ struct exynos5_i2c {
 	unsigned int		irq;
 
 	void __iomem		*regs;
-	struct clk		*clk;
+	struct clk		*clk;		/* operating clock */
+	struct clk		*pclk;		/* bus clock */
 	struct device		*dev;
 	int			state;
 

@@ -757,10 +758,14 @@ static int exynos5_i2c_xfer(struct i2c_adapter *adap,
 	struct exynos5_i2c *i2c = adap->algo_data;
 	int i, ret;
 
-	ret = clk_enable(i2c->clk);
+	ret = clk_enable(i2c->pclk);
 	if (ret)
 		return ret;
 
+	ret = clk_enable(i2c->clk);
+	if (ret)
+		goto err_pclk;
+
 	for (i = 0; i < num; ++i) {
 		ret = exynos5_i2c_xfer_msg(i2c, msgs + i, i + 1 == num);
 		if (ret)

@@ -768,6 +773,8 @@ static int exynos5_i2c_xfer(struct i2c_adapter *adap,
 	}
 
 	clk_disable(i2c->clk);
+err_pclk:
+	clk_disable(i2c->pclk);
 
 	return ret ?: num;
 }

@@ -807,10 +814,18 @@ static int exynos5_i2c_probe(struct platform_device *pdev)
 		return -ENOENT;
 	}
 
-	ret = clk_prepare_enable(i2c->clk);
+	i2c->pclk = devm_clk_get(&pdev->dev, "hsi2c_pclk");
+	if (IS_ERR(i2c->pclk))
+		i2c->pclk = NULL; /* pclk is optional */
+
+	ret = clk_prepare_enable(i2c->pclk);
 	if (ret)
 		return ret;
 
+	ret = clk_prepare_enable(i2c->clk);
+	if (ret)
+		goto err_pclk;
+
 	i2c->regs = devm_platform_ioremap_resource(pdev, 0);
 	if (IS_ERR(i2c->regs)) {
 		ret = PTR_ERR(i2c->regs);

@@ -853,6 +868,7 @@ static int exynos5_i2c_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, i2c);
 
 	clk_disable(i2c->clk);
+	clk_disable(i2c->pclk);
 
 	dev_info(&pdev->dev, "%s: HSI2C adapter\n", dev_name(&i2c->adap.dev));
 

@@ -860,6 +876,9 @@ static int exynos5_i2c_probe(struct platform_device *pdev)
 
  err_clk:
 	clk_disable_unprepare(i2c->clk);
+
+ err_pclk:
+	clk_disable_unprepare(i2c->pclk);
 	return ret;
 }
 

@@ -870,6 +889,7 @@ static int exynos5_i2c_remove(struct platform_device *pdev)
 	i2c_del_adapter(&i2c->adap);
 
 	clk_unprepare(i2c->clk);
+	clk_unprepare(i2c->pclk);
 
 	return 0;
 }

@@ -881,6 +901,7 @@ static int exynos5_i2c_suspend_noirq(struct device *dev)
 
 	i2c_mark_adapter_suspended(&i2c->adap);
 	clk_unprepare(i2c->clk);
+	clk_unprepare(i2c->pclk);
 
 	return 0;
 }

@@ -890,21 +911,30 @@ static int exynos5_i2c_resume_noirq(struct device *dev)
 	struct exynos5_i2c *i2c = dev_get_drvdata(dev);
 	int ret = 0;
 
-	ret = clk_prepare_enable(i2c->clk);
+	ret = clk_prepare_enable(i2c->pclk);
 	if (ret)
 		return ret;
 
+	ret = clk_prepare_enable(i2c->clk);
+	if (ret)
+		goto err_pclk;
+
 	ret = exynos5_hsi2c_clock_setup(i2c);
-	if (ret) {
-		clk_disable_unprepare(i2c->clk);
-		return ret;
-	}
+	if (ret)
+		goto err_clk;
 
 	exynos5_i2c_init(i2c);
 	clk_disable(i2c->clk);
+	clk_disable(i2c->pclk);
 	i2c_mark_adapter_resumed(&i2c->adap);
 
 	return 0;
+
+err_clk:
+	clk_disable_unprepare(i2c->clk);
+err_pclk:
+	clk_disable_unprepare(i2c->pclk);
+	return ret;
 }
 #endif
 

@@ -617,7 +617,7 @@ config I2C_EXYNOS5
 	help
 	  High-speed I2C controller on Samsung Exynos5 and newer Samsung SoCs:
 	  Exynos5250, Exynos5260, Exynos5410, Exynos542x, Exynos5800,
-	  Exynos5433 and Exynos7.
+	  Exynos5433, Exynos7, Exynos850 and ExynosAutoV9.
 	  Choose Y here only if you build for such Samsung SoC.
 
 config I2C_GPIO