1 files changed, 141 insertions, 55 deletions

diff --git a/drivers/i2c/busses/i2c-designware-core.c b/drivers/i2c/busses/i2c-designware-core.c
index c6922b806fb7..52a603a01ddd 100644
--- a/drivers/i2c/busses/i2c-designware-core.c
+++ b/drivers/i2c/busses/i2c-designware-core.c
@@ -42,6 +42,8 @@
 #define DW_IC_SS_SCL_LCNT	0x18
 #define DW_IC_FS_SCL_HCNT	0x1c
 #define DW_IC_FS_SCL_LCNT	0x20
+#define DW_IC_HS_SCL_HCNT	0x24
+#define DW_IC_HS_SCL_LCNT	0x28
 #define DW_IC_INTR_STAT		0x2c
 #define DW_IC_INTR_MASK		0x30
 #define DW_IC_RAW_INTR_STAT	0x34
@@ -89,12 +91,17 @@
 					 DW_IC_INTR_TX_ABRT | \
 					 DW_IC_INTR_STOP_DET)
 
-#define DW_IC_STATUS_ACTIVITY	0x1
+#define DW_IC_STATUS_ACTIVITY		0x1
+#define DW_IC_STATUS_TFE		BIT(2)
+#define DW_IC_STATUS_MST_ACTIVITY	BIT(5)
 
 #define DW_IC_ERR_TX_ABRT	0x1
 
 #define DW_IC_TAR_10BITADDR_MASTER BIT(12)
 
+#define DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH	(BIT(2) | BIT(3))
+#define DW_IC_COMP_PARAM_1_SPEED_MODE_MASK	GENMASK(3, 2)
+
 /*
  * status codes
  */
@@ -252,10 +259,15 @@ static u32 i2c_dw_scl_lcnt(u32 ic_clk, u32 tLOW, u32 tf, int offset)
 
 static void __i2c_dw_enable(struct dw_i2c_dev *dev, bool enable)
 {
+	dw_writel(dev, enable, DW_IC_ENABLE);
+}
+
+static void __i2c_dw_enable_and_wait(struct dw_i2c_dev *dev, bool enable)
+{
 	int timeout = 100;
 
 	do {
-		dw_writel(dev, enable, DW_IC_ENABLE);
+		__i2c_dw_enable(dev, enable);
 		if ((dw_readl(dev, DW_IC_ENABLE_STATUS) & 1) == enable)
 			return;
 
@@ -282,6 +294,28 @@ static unsigned long i2c_dw_clk_rate(struct dw_i2c_dev *dev)
 	return dev->get_clk_rate_khz(dev);
 }
 
+static int i2c_dw_acquire_lock(struct dw_i2c_dev *dev)
+{
+	int ret;
+
+	if (!dev->acquire_lock)
+		return 0;
+
+	ret = dev->acquire_lock(dev);
+	if (!ret)
+		return 0;
+
+	dev_err(dev->dev, "couldn't acquire bus ownership\n");
+
+	return ret;
+}
+
+static void i2c_dw_release_lock(struct dw_i2c_dev *dev)
+{
+	if (dev->release_lock)
+		dev->release_lock(dev);
+}
+
 /**
  * i2c_dw_init() - initialize the designware i2c master hardware
  * @dev: device private data
@@ -293,17 +327,13 @@ static unsigned long i2c_dw_clk_rate(struct dw_i2c_dev *dev)
 int i2c_dw_init(struct dw_i2c_dev *dev)
 {
 	u32 hcnt, lcnt;
-	u32 reg;
+	u32 reg, comp_param1;
 	u32 sda_falling_time, scl_falling_time;
 	int ret;
 
-	if (dev->acquire_lock) {
-		ret = dev->acquire_lock(dev);
-		if (ret) {
-			dev_err(dev->dev, "couldn't acquire bus ownership\n");
-			return ret;
-		}
-	}
+	ret = i2c_dw_acquire_lock(dev);
+	if (ret)
+		return ret;
 
 	reg = dw_readl(dev, DW_IC_COMP_TYPE);
 	if (reg == ___constant_swab32(DW_IC_COMP_TYPE_VALUE)) {
@@ -315,13 +345,14 @@ int i2c_dw_init(struct dw_i2c_dev *dev)
 	} else if (reg != DW_IC_COMP_TYPE_VALUE) {
 		dev_err(dev->dev, "Unknown Synopsys component type: "
 			"0x%08x\n", reg);
-		if (dev->release_lock)
-			dev->release_lock(dev);
+		i2c_dw_release_lock(dev);
 		return -ENODEV;
 	}
 
+	comp_param1 = dw_readl(dev, DW_IC_COMP_PARAM_1);
+
 	/* Disable the adapter */
-	__i2c_dw_enable(dev, false);
+	__i2c_dw_enable_and_wait(dev, false);
 
 	/* set standard and fast speed deviders for high/low periods */
 
@@ -347,8 +378,11 @@ int i2c_dw_init(struct dw_i2c_dev *dev)
 	dw_writel(dev, lcnt, DW_IC_SS_SCL_LCNT);
 	dev_dbg(dev->dev, "Standard-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt);
 
-	/* Set SCL timing parameters for fast-mode */
-	if (dev->fs_hcnt && dev->fs_lcnt) {
+	/* Set SCL timing parameters for fast-mode or fast-mode plus */
+	if ((dev->clk_freq == 1000000) && dev->fp_hcnt && dev->fp_lcnt) {
+		hcnt = dev->fp_hcnt;
+		lcnt = dev->fp_lcnt;
+	} else if (dev->fs_hcnt && dev->fs_lcnt) {
 		hcnt = dev->fs_hcnt;
 		lcnt = dev->fs_lcnt;
 	} else {
@@ -366,6 +400,23 @@ int i2c_dw_init(struct dw_i2c_dev *dev)
 	dw_writel(dev, lcnt, DW_IC_FS_SCL_LCNT);
 	dev_dbg(dev->dev, "Fast-mode HCNT:LCNT = %d:%d\n", hcnt, lcnt);
 
+	if ((dev->master_cfg & DW_IC_CON_SPEED_MASK) ==
+		DW_IC_CON_SPEED_HIGH) {
+		if ((comp_param1 & DW_IC_COMP_PARAM_1_SPEED_MODE_MASK)
+			!= DW_IC_COMP_PARAM_1_SPEED_MODE_HIGH) {
+			dev_err(dev->dev, "High Speed not supported!\n");
+			dev->master_cfg &= ~DW_IC_CON_SPEED_MASK;
+			dev->master_cfg |= DW_IC_CON_SPEED_FAST;
+		} else if (dev->hs_hcnt && dev->hs_lcnt) {
+			hcnt = dev->hs_hcnt;
+			lcnt = dev->hs_lcnt;
+			dw_writel(dev, hcnt, DW_IC_HS_SCL_HCNT);
+			dw_writel(dev, lcnt, DW_IC_HS_SCL_LCNT);
+			dev_dbg(dev->dev, "HighSpeed-mode HCNT:LCNT = %d:%d\n",
+				hcnt, lcnt);
+		}
+	}
+
 	/* Configure SDA Hold Time if required */
 	if (dev->sda_hold_time) {
 		reg = dw_readl(dev, DW_IC_COMP_VERSION);
@@ -383,8 +434,8 @@ int i2c_dw_init(struct dw_i2c_dev *dev)
 	/* configure the i2c master */
 	dw_writel(dev, dev->master_cfg , DW_IC_CON);
 
-	if (dev->release_lock)
-		dev->release_lock(dev);
+	i2c_dw_release_lock(dev);
+
 	return 0;
 }
 EXPORT_SYMBOL_GPL(i2c_dw_init);
@@ -411,27 +462,45 @@ static int i2c_dw_wait_bus_not_busy(struct dw_i2c_dev *dev)
 static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
 {
 	struct i2c_msg *msgs = dev->msgs;
-	u32 ic_con, ic_tar = 0;
+	u32 ic_tar = 0;
+	bool enabled;
 
-	/* Disable the adapter */
-	__i2c_dw_enable(dev, false);
+	enabled = dw_readl(dev, DW_IC_ENABLE_STATUS) & 1;
+
+	if (enabled) {
+		u32 ic_status;
+
+		/*
+		 * Only disable adapter if ic_tar and ic_con can't be
+		 * dynamically updated
+		 */
+		ic_status = dw_readl(dev, DW_IC_STATUS);
+		if (!dev->dynamic_tar_update_enabled ||
+		    (ic_status & DW_IC_STATUS_MST_ACTIVITY) ||
+		    !(ic_status & DW_IC_STATUS_TFE)) {
+			__i2c_dw_enable_and_wait(dev, false);
+			enabled = false;
+		}
+	}
 
 	/* if the slave address is ten bit address, enable 10BITADDR */
-	ic_con = dw_readl(dev, DW_IC_CON);
-	if (msgs[dev->msg_write_idx].flags & I2C_M_TEN) {
-		ic_con |= DW_IC_CON_10BITADDR_MASTER;
+	if (dev->dynamic_tar_update_enabled) {
 		/*
 		 * If I2C_DYNAMIC_TAR_UPDATE is set, the 10-bit addressing
-		 * mode has to be enabled via bit 12 of IC_TAR register.
-		 * We set it always as I2C_DYNAMIC_TAR_UPDATE can't be
-		 * detected from registers.
+		 * mode has to be enabled via bit 12 of IC_TAR register,
+		 * otherwise bit 4 of IC_CON is used.
 		 */
-		ic_tar = DW_IC_TAR_10BITADDR_MASTER;
+		if (msgs[dev->msg_write_idx].flags & I2C_M_TEN)
+			ic_tar = DW_IC_TAR_10BITADDR_MASTER;
 	} else {
-		ic_con &= ~DW_IC_CON_10BITADDR_MASTER;
-	}
+		u32 ic_con = dw_readl(dev, DW_IC_CON);
 
-	dw_writel(dev, ic_con, DW_IC_CON);
+		if (msgs[dev->msg_write_idx].flags & I2C_M_TEN)
+			ic_con |= DW_IC_CON_10BITADDR_MASTER;
+		else
+			ic_con &= ~DW_IC_CON_10BITADDR_MASTER;
+		dw_writel(dev, ic_con, DW_IC_CON);
+	}
 
 	/*
 	 * Set the slave (target) address and enable 10-bit addressing mode
@@ -442,8 +511,8 @@ static void i2c_dw_xfer_init(struct dw_i2c_dev *dev)
 	/* enforce disabled interrupts (due to HW issues) */
 	i2c_dw_disable_int(dev);
 
-	/* Enable the adapter */
-	__i2c_dw_enable(dev, true);
+	if (!enabled)
+		__i2c_dw_enable(dev, true);
 
 	/* Clear and enable interrupts */
 	dw_readl(dev, DW_IC_CLR_INTR);
@@ -624,7 +693,8 @@ static int i2c_dw_handle_tx_abort(struct dw_i2c_dev *dev)
 }
 
 /*
- * Prepare controller for a transaction and call i2c_dw_xfer_msg
+ * Prepare controller for a transaction and start transfer by calling
+ * i2c_dw_xfer_init()
  */
 static int
 i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
@@ -647,13 +717,9 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 	dev->abort_source = 0;
 	dev->rx_outstanding = 0;
 
-	if (dev->acquire_lock) {
-		ret = dev->acquire_lock(dev);
-		if (ret) {
-			dev_err(dev->dev, "couldn't acquire bus ownership\n");
-			goto done_nolock;
-		}
-	}
+	ret = i2c_dw_acquire_lock(dev);
+	if (ret)
+		goto done_nolock;
 
 	ret = i2c_dw_wait_bus_not_busy(dev);
 	if (ret < 0)
@@ -671,16 +737,6 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 		goto done;
 	}
 
-	/*
-	 * We must disable the adapter before returning and signaling the end
-	 * of the current transfer. Otherwise the hardware might continue
-	 * generating interrupts which in turn causes a race condition with
-	 * the following transfer.  Needs some more investigation if the
-	 * additional interrupts are a hardware bug or this driver doesn't
-	 * handle them correctly yet.
-	 */
-	__i2c_dw_enable(dev, false);
-
 	if (dev->msg_err) {
 		ret = dev->msg_err;
 		goto done;
@@ -700,8 +756,7 @@ i2c_dw_xfer(struct i2c_adapter *adap, struct i2c_msg msgs[], int num)
 	ret = -EIO;
 
 done:
-	if (dev->release_lock)
-		dev->release_lock(dev);
+	i2c_dw_release_lock(dev);
 
 done_nolock:
 	pm_runtime_mark_last_busy(dev->dev);
@@ -818,9 +873,19 @@ static irqreturn_t i2c_dw_isr(int this_irq, void *dev_id)
 	 */
 
 tx_aborted:
-	if ((stat & (DW_IC_INTR_TX_ABRT | DW_IC_INTR_STOP_DET)) || dev->msg_err)
+	if ((stat & (DW_IC_INTR_TX_ABRT | DW_IC_INTR_STOP_DET))
+			|| dev->msg_err) {
+		/*
+		 * We must disable interruts before returning and signaling
+		 * the end of the current transfer. Otherwise the hardware
+		 * might continue generating interrupts for non-existent
+		 * transfers.
+		 */
+		i2c_dw_disable_int(dev);
+		dw_readl(dev, DW_IC_CLR_INTR);
+
 		complete(&dev->cmd_complete);
-	else if (unlikely(dev->accessor_flags & ACCESS_INTR_MASK)) {
+	} else if (unlikely(dev->accessor_flags & ACCESS_INTR_MASK)) {
 		/* workaround to trigger pending interrupt */
 		stat = dw_readl(dev, DW_IC_INTR_MASK);
 		i2c_dw_disable_int(dev);
@@ -833,7 +898,7 @@ tx_aborted:
 void i2c_dw_disable(struct dw_i2c_dev *dev)
 {
 	/* Disable controller */
-	__i2c_dw_enable(dev, false);
+	__i2c_dw_enable_and_wait(dev, false);
 
 	/* Disable all interupts */
 	dw_writel(dev, 0, DW_IC_INTR_MASK);
@@ -857,6 +922,7 @@ int i2c_dw_probe(struct dw_i2c_dev *dev)
 {
 	struct i2c_adapter *adap = &dev->adapter;
 	int r;
+	u32 reg;
 
 	init_completion(&dev->cmd_complete);
 
@@ -864,6 +930,26 @@ int i2c_dw_probe(struct dw_i2c_dev *dev)
 	if (r)
 		return r;
 
+	r = i2c_dw_acquire_lock(dev);
+	if (r)
+		return r;
+
+	/*
+	 * Test if dynamic TAR update is enabled in this controller by writing
+	 * to IC_10BITADDR_MASTER field in IC_CON: when it is enabled this
+	 * field is read-only so it should not succeed
+	 */
+	reg = dw_readl(dev, DW_IC_CON);
+	dw_writel(dev, reg ^ DW_IC_CON_10BITADDR_MASTER, DW_IC_CON);
+
+	if ((dw_readl(dev, DW_IC_CON) & DW_IC_CON_10BITADDR_MASTER) ==
+	    (reg & DW_IC_CON_10BITADDR_MASTER)) {
+		dev->dynamic_tar_update_enabled = true;
+		dev_dbg(dev->dev, "Dynamic TAR update enabled");
+	}
+
+	i2c_dw_release_lock(dev);
+
 	snprintf(adap->name, sizeof(adap->name),
 		 "Synopsys DesignWare I2C adapter");
 	adap->retries = 3;