Merge branch 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/…

…kernel/git/wsa/linux Pull i2c fixes from Wolfram Sang: "Two bugfixes, one v4.16 regression fix, and two documentation fixes" * 'i2c/for-current' of git://git.kernel.org/pub/scm/linux/kernel/git/wsa/linux: i2c: designware: Consider SCL GPIO optional i2c: busses: i2c-sirf: Fix spelling: "formular" -> "formula". i2c: bcm2835: Set up the rising/falling edge delays i2c: i801: Add missing documentation entries for Braswell and Kaby Lake i2c: designware: must wait for enable
chewitt · Feb 23, 2018 · 938e142 · 938e142
2 parents 170e07b + d1fa745
commit 938e142
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Showing 6 changed files with 29 additions and 5 deletions.
diff --git a/Documentation/i2c/busses/i2c-i801 b/Documentation/i2c/busses/i2c-i801
@@ -28,8 +28,10 @@ Supported adapters:
   * Intel Wildcat Point (PCH)
   * Intel Wildcat Point-LP (PCH)
   * Intel BayTrail (SOC)
+  * Intel Braswell (SOC)
   * Intel Sunrise Point-H (PCH)
   * Intel Sunrise Point-LP (PCH)
+  * Intel Kaby Lake-H (PCH)
   * Intel DNV (SOC)
   * Intel Broxton (SOC)
   * Intel Lewisburg (PCH)

diff --git a/drivers/i2c/busses/Kconfig b/drivers/i2c/busses/Kconfig
@@ -123,8 +123,10 @@ config I2C_I801
 	    Wildcat Point (PCH)
 	    Wildcat Point-LP (PCH)
 	    BayTrail (SOC)
+	    Braswell (SOC)
 	    Sunrise Point-H (PCH)
 	    Sunrise Point-LP (PCH)
+	    Kaby Lake-H (PCH)
 	    DNV (SOC)
 	    Broxton (SOC)
 	    Lewisburg (PCH)

diff --git a/drivers/i2c/busses/i2c-bcm2835.c b/drivers/i2c/busses/i2c-bcm2835.c
@@ -50,6 +50,9 @@
 #define BCM2835_I2C_S_CLKT	BIT(9)
 #define BCM2835_I2C_S_LEN	BIT(10) /* Fake bit for SW error reporting */
 
+#define BCM2835_I2C_FEDL_SHIFT	16
+#define BCM2835_I2C_REDL_SHIFT	0
+
 #define BCM2835_I2C_CDIV_MIN	0x0002
 #define BCM2835_I2C_CDIV_MAX	0xFFFE
 
@@ -81,7 +84,7 @@ static inline u32 bcm2835_i2c_readl(struct bcm2835_i2c_dev *i2c_dev, u32 reg)
 
 static int bcm2835_i2c_set_divider(struct bcm2835_i2c_dev *i2c_dev)
 {
-	u32 divider;
+	u32 divider, redl, fedl;
 
 	divider = DIV_ROUND_UP(clk_get_rate(i2c_dev->clk),
 			       i2c_dev->bus_clk_rate);
@@ -100,6 +103,22 @@ static int bcm2835_i2c_set_divider(struct bcm2835_i2c_dev *i2c_dev)
 
 	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_DIV, divider);
 
+	/*
+	 * Number of core clocks to wait after falling edge before
+	 * outputting the next data bit.  Note that both FEDL and REDL
+	 * can't be greater than CDIV/2.
+	 */
+	fedl = max(divider / 16, 1u);
+
+	/*
+	 * Number of core clocks to wait after rising edge before
+	 * sampling the next incoming data bit.
+	 */
+	redl = max(divider / 4, 1u);
+
+	bcm2835_i2c_writel(i2c_dev, BCM2835_I2C_DEL,
+			   (fedl << BCM2835_I2C_FEDL_SHIFT) |
+			   (redl << BCM2835_I2C_REDL_SHIFT));
 	return 0;
 }
 

diff --git a/drivers/i2c/busses/i2c-designware-master.c b/drivers/i2c/busses/i2c-designware-master.c
@@ -209,7 +209,7 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
 	i2c_dw_disable_int(dev);
 
 	/* Enable the adapter */
-	__i2c_dw_enable(dev, true);
+	__i2c_dw_enable_and_wait(dev, true);
 
 	/* Clear and enable interrupts */
 	dw_readl(dev, DW_IC_CLR_INTR);
@@ -644,7 +644,7 @@ static int i2c_dw_init_recovery_info(struct dw_i2c_dev *dev)
 	gpio = devm_gpiod_get(dev->dev, "scl", GPIOD_OUT_HIGH);
 	if (IS_ERR(gpio)) {
 		r = PTR_ERR(gpio);
-		if (r == -ENOENT)
+		if (r == -ENOENT || r == -ENOSYS)
 			return 0;
 		return r;
 	}

diff --git a/drivers/i2c/busses/i2c-i801.c b/drivers/i2c/busses/i2c-i801.c
@@ -58,6 +58,7 @@
  * Wildcat Point (PCH)		0x8ca2	32	hard	yes	yes	yes
  * Wildcat Point-LP (PCH)	0x9ca2	32	hard	yes	yes	yes
  * BayTrail (SOC)		0x0f12	32	hard	yes	yes	yes
+ * Braswell (SOC)		0x2292	32	hard	yes	yes	yes
  * Sunrise Point-H (PCH) 	0xa123  32	hard	yes	yes	yes
  * Sunrise Point-LP (PCH)	0x9d23	32	hard	yes	yes	yes
  * DNV (SOC)			0x19df	32	hard	yes	yes	yes

diff --git a/drivers/i2c/busses/i2c-sirf.c b/drivers/i2c/busses/i2c-sirf.c
@@ -341,7 +341,7 @@ static int i2c_sirfsoc_probe(struct platform_device *pdev)
 	platform_set_drvdata(pdev, adap);
 	init_completion(&siic->done);
 
-	/* Controller Initalisation */
+	/* Controller initialisation */
 
 	writel(SIRFSOC_I2C_RESET, siic->base + SIRFSOC_I2C_CTRL);
 	while (readl(siic->base + SIRFSOC_I2C_CTRL) & SIRFSOC_I2C_RESET)
@@ -369,7 +369,7 @@ static int i2c_sirfsoc_probe(struct platform_device *pdev)
 	 * but they start to affect the speed when clock is set to faster
 	 * frequencies.
 	 * Through the actual tests, use the different user_div value(which
-	 * in the divider formular 'Fio / (Fi2c * user_div)') to adapt
+	 * in the divider formula 'Fio / (Fi2c * user_div)') to adapt
 	 * the different ranges of i2c bus clock frequency, to make the SCL
 	 * more accurate.
 	 */