1 files changed, 111 insertions, 26 deletions

diff --git a/drivers/net/can/c_can/c_can_platform.c b/drivers/net/can/c_can/c_can_platform.c
index d63b91904f8..12430be6448 100644
--- a/drivers/net/can/c_can/c_can_platform.c
+++ b/drivers/net/can/c_can/c_can_platform.c
@@ -32,54 +32,131 @@
 #include <linux/clk.h>
 #include <linux/of.h>
 #include <linux/of_device.h>
-#include <linux/pinctrl/consumer.h>
 
 #include <linux/can/dev.h>
 
 #include "c_can.h"
 
-#define CAN_RAMINIT_START_MASK(i)	(1 << (i))
-
+#define CAN_RAMINIT_START_MASK(i)	(0x001 << (i))
+#define CAN_RAMINIT_DONE_MASK(i)	(0x100 << (i))
+#define CAN_RAMINIT_ALL_MASK(i)		(0x101 << (i))
+#define DCAN_RAM_INIT_BIT		(1 << 3)
+static DEFINE_SPINLOCK(raminit_lock);
 /*
  * 16-bit c_can registers can be arranged differently in the memory
  * architecture of different implementations. For example: 16-bit
  * registers can be aligned to a 16-bit boundary or 32-bit boundary etc.
  * Handle the same by providing a common read/write interface.
  */
-static u16 c_can_plat_read_reg_aligned_to_16bit(struct c_can_priv *priv,
+static u16 c_can_plat_read_reg_aligned_to_16bit(const struct c_can_priv *priv,
 						enum reg index)
 {
 	return readw(priv->base + priv->regs[index]);
 }
 
-static void c_can_plat_write_reg_aligned_to_16bit(struct c_can_priv *priv,
+static void c_can_plat_write_reg_aligned_to_16bit(const struct c_can_priv *priv,
 						enum reg index, u16 val)
 {
 	writew(val, priv->base + priv->regs[index]);
 }
 
-static u16 c_can_plat_read_reg_aligned_to_32bit(struct c_can_priv *priv,
+static u16 c_can_plat_read_reg_aligned_to_32bit(const struct c_can_priv *priv,
 						enum reg index)
 {
 	return readw(priv->base + 2 * priv->regs[index]);
 }
 
-static void c_can_plat_write_reg_aligned_to_32bit(struct c_can_priv *priv,
+static void c_can_plat_write_reg_aligned_to_32bit(const struct c_can_priv *priv,
 						enum reg index, u16 val)
 {
 	writew(val, priv->base + 2 * priv->regs[index]);
 }
 
-static void c_can_hw_raminit(const struct c_can_priv *priv, bool enable)
+static void c_can_hw_raminit_wait_ti(const struct c_can_priv *priv, u32 mask,
+				  u32 val)
+{
+	/* We look only at the bits of our instance. */
+	val &= mask;
+	while ((readl(priv->raminit_ctrlreg) & mask) != val)
+		udelay(1);
+}
+
+static void c_can_hw_raminit_ti(const struct c_can_priv *priv, bool enable)
+{
+	u32 mask = CAN_RAMINIT_ALL_MASK(priv->instance);
+	u32 ctrl;
+
+	spin_lock(&raminit_lock);
+
+	ctrl = readl(priv->raminit_ctrlreg);
+	/* We clear the done and start bit first. The start bit is
+	 * looking at the 0 -> transition, but is not self clearing;
+	 * And we clear the init done bit as well.
+	 */
+	ctrl &= ~CAN_RAMINIT_START_MASK(priv->instance);
+	ctrl |= CAN_RAMINIT_DONE_MASK(priv->instance);
+	writel(ctrl, priv->raminit_ctrlreg);
+	ctrl &= ~CAN_RAMINIT_DONE_MASK(priv->instance);
+	c_can_hw_raminit_wait_ti(priv, ctrl, mask);
+
+	if (enable) {
+		/* Set start bit and wait for the done bit. */
+		ctrl |= CAN_RAMINIT_START_MASK(priv->instance);
+		writel(ctrl, priv->raminit_ctrlreg);
+		ctrl |= CAN_RAMINIT_DONE_MASK(priv->instance);
+		c_can_hw_raminit_wait_ti(priv, ctrl, mask);
+	}
+	spin_unlock(&raminit_lock);
+}
+
+static u32 c_can_plat_read_reg32(const struct c_can_priv *priv, enum reg index)
 {
 	u32 val;
 
-	val = readl(priv->raminit_ctrlreg);
-	if (enable)
-		val |= CAN_RAMINIT_START_MASK(priv->instance);
-	else
-		val &= ~CAN_RAMINIT_START_MASK(priv->instance);
-	writel(val, priv->raminit_ctrlreg);
+	val = priv->read_reg(priv, index);
+	val |= ((u32) priv->read_reg(priv, index + 1)) << 16;
+
+	return val;
+}
+
+static void c_can_plat_write_reg32(const struct c_can_priv *priv, enum reg index,
+		u32 val)
+{
+	priv->write_reg(priv, index + 1, val >> 16);
+	priv->write_reg(priv, index, val);
+}
+
+static u32 d_can_plat_read_reg32(const struct c_can_priv *priv, enum reg index)
+{
+	return readl(priv->base + priv->regs[index]);
+}
+
+static void d_can_plat_write_reg32(const struct c_can_priv *priv, enum reg index,
+		u32 val)
+{
+	writel(val, priv->base + priv->regs[index]);
+}
+
+static void c_can_hw_raminit_wait(const struct c_can_priv *priv, u32 mask)
+{
+	while (priv->read_reg32(priv, C_CAN_FUNCTION_REG) & mask)
+		udelay(1);
+}
+
+static void c_can_hw_raminit(const struct c_can_priv *priv, bool enable)
+{
+	u32 ctrl;
+
+	ctrl = priv->read_reg32(priv, C_CAN_FUNCTION_REG);
+	ctrl &= ~DCAN_RAM_INIT_BIT;
+	priv->write_reg32(priv, C_CAN_FUNCTION_REG, ctrl);
+	c_can_hw_raminit_wait(priv, ctrl);
+
+	if (enable) {
+		ctrl |= DCAN_RAM_INIT_BIT;
+		priv->write_reg32(priv, C_CAN_FUNCTION_REG, ctrl);
+		c_can_hw_raminit_wait(priv, ctrl);
+	}
 }
 
 static struct platform_device_id c_can_id_table[] = {
@@ -114,7 +191,6 @@ static int c_can_plat_probe(struct platform_device *pdev)
 	struct c_can_priv *priv;
 	const struct of_device_id *match;
 	const struct platform_device_id *id;
-	struct pinctrl *pinctrl;
 	struct resource *mem, *res;
 	int irq;
 	struct clk *clk;
@@ -131,11 +207,6 @@ static int c_can_plat_probe(struct platform_device *pdev)
 		id = platform_get_device_id(pdev);
 	}
 
-	pinctrl = devm_pinctrl_get_select_default(&pdev->dev);
-	if (IS_ERR(pinctrl))
-		dev_warn(&pdev->dev,
-			"failed to configure pins from driver\n");
-
 	/* get the appropriate clk */
 	clk = clk_get(&pdev->dev, NULL);
 	if (IS_ERR(clk)) {
@@ -181,11 +252,15 @@ static int c_can_plat_probe(struct platform_device *pdev)
 		case IORESOURCE_MEM_32BIT:
 			priv->read_reg = c_can_plat_read_reg_aligned_to_32bit;
 			priv->write_reg = c_can_plat_write_reg_aligned_to_32bit;
+			priv->read_reg32 = c_can_plat_read_reg32;
+			priv->write_reg32 = c_can_plat_write_reg32;
 			break;
 		case IORESOURCE_MEM_16BIT:
 		default:
 			priv->read_reg = c_can_plat_read_reg_aligned_to_16bit;
 			priv->write_reg = c_can_plat_write_reg_aligned_to_16bit;
+			priv->read_reg32 = c_can_plat_read_reg32;
+			priv->write_reg32 = c_can_plat_write_reg32;
 			break;
 		}
 		break;
@@ -194,6 +269,8 @@ static int c_can_plat_probe(struct platform_device *pdev)
 		priv->can.ctrlmode_supported |= CAN_CTRLMODE_3_SAMPLES;
 		priv->read_reg = c_can_plat_read_reg_aligned_to_16bit;
 		priv->write_reg = c_can_plat_write_reg_aligned_to_16bit;
+		priv->read_reg32 = d_can_plat_read_reg32;
+		priv->write_reg32 = d_can_plat_write_reg32;
 
 		if (pdev->dev.of_node)
 			priv->instance = of_alias_get_id(pdev->dev.of_node, "d_can");
@@ -201,11 +278,21 @@ static int c_can_plat_probe(struct platform_device *pdev)
 			priv->instance = pdev->id;
 
 		res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
-		priv->raminit_ctrlreg =	devm_request_and_ioremap(&pdev->dev, res);
-		if (!priv->raminit_ctrlreg || priv->instance < 0)
+		/* Not all D_CAN modules have a separate register for the D_CAN
+		 * RAM initialization. Use default RAM init bit in D_CAN module
+		 * if not specified in DT.
+		 */
+		if (!res) {
+			priv->raminit = c_can_hw_raminit;
+			break;
+		}
+
+		priv->raminit_ctrlreg = devm_ioremap(&pdev->dev, res->start,
+						     resource_size(res));
+		if (IS_ERR(priv->raminit_ctrlreg) || priv->instance < 0)
 			dev_info(&pdev->dev, "control memory is not used for raminit\n");
 		else
-			priv->raminit = c_can_hw_raminit;
+			priv->raminit = c_can_hw_raminit_ti;
 		break;
 	default:
 		ret = -EINVAL;
@@ -234,7 +321,6 @@ static int c_can_plat_probe(struct platform_device *pdev)
 	return 0;
 
 exit_free_device:
-	platform_set_drvdata(pdev, NULL);
 	free_c_can_dev(dev);
 exit_iounmap:
 	iounmap(addr);
@@ -255,7 +341,6 @@ static int c_can_plat_remove(struct platform_device *pdev)
 	struct resource *mem;
 
 	unregister_c_can_dev(dev);
-	platform_set_drvdata(pdev, NULL);
 
 	free_c_can_dev(dev);
 	iounmap(priv->base);
@@ -331,7 +416,7 @@ static struct platform_driver c_can_plat_driver = {
 	.driver = {
 		.name = KBUILD_MODNAME,
 		.owner = THIS_MODULE,
-		.of_match_table = of_match_ptr(c_can_of_table),
+		.of_match_table = c_can_of_table,
 	},
 	.probe = c_can_plat_probe,
 	.remove = c_can_plat_remove,