1 files changed, 75 insertions, 0 deletions
diff --git a/drivers/net/can/spi/mcp25xxfd/mcp25xxfd_ecc.c b/drivers/net/can/spi/mcp25xxfd/mcp25xxfd_ecc.c
new file mode 100644
index 000000000000..526f345d0a17
--- /dev/null
+++ b/drivers/net/can/spi/mcp25xxfd/mcp25xxfd_ecc.c
@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0
+
+/* CAN bus driver for Microchip 25XXFD CAN Controller with SPI Interface
+ *
+ * Copyright 2019 Martin Sperl <kernel@martin.sperl.org>
+ */
+
+#include <linux/kernel.h>
+#include <linux/spi/spi.h>
+#include "mcp25xxfd_cmd.h"
+#include "mcp25xxfd_ecc.h"
+#include "mcp25xxfd_priv.h"
+#include "mcp25xxfd_regs.h"
+
+int mcp25xxfd_ecc_clear_int(struct mcp25xxfd_priv *priv)
+{
+	u32 val, addr;
+	int ret;
+
+	/* first report the error address */
+	ret = mcp25xxfd_cmd_read(priv->spi, MCP25XXFD_ECCSTAT, &val);
+	if (ret)
+		return ret;
+
+	/* if no flags are set then nothing to do */
+	if (!(val & (MCP25XXFD_ECCSTAT_SECIF | MCP25XXFD_ECCSTAT_DEDIF)))
+		return 0;
+
+	addr = (val & MCP25XXFD_ECCSTAT_ERRADDR_MASK) >>
+		MCP25XXFD_ECCSTAT_ERRADDR_SHIFT;
+
+	dev_err_ratelimited(&priv->spi->dev, "ECC %s bit error at %03x\n",
+			    (val & MCP25XXFD_ECCSTAT_DEDIF) ?
+			    "double" : "single",
+			    addr);
+
+	/* and clear the error */
+	return mcp25xxfd_cmd_write_mask(priv->spi, MCP25XXFD_ECCSTAT, 0,
+					MCP25XXFD_ECCSTAT_SECIF |
+					MCP25XXFD_ECCSTAT_DEDIF);
+}
+
+int mcp25xxfd_ecc_enable_int(struct mcp25xxfd_priv *priv, bool enable)
+{
+	u32 mask = MCP25XXFD_ECCCON_SECIE | MCP25XXFD_ECCCON_DEDIE;
+
+	priv->regs.ecccon &= ~mask;
+	priv->regs.ecccon |= MCP25XXFD_ECCCON_ECCEN | (enable ? mask : 0);
+
+	return mcp25xxfd_cmd_write_mask(priv->spi, MCP25XXFD_ECCCON,
+					priv->regs.ecccon,
+					MCP25XXFD_ECCCON_ECCEN | mask);
+}
+
+int mcp25xxfd_ecc_enable(struct mcp25xxfd_priv *priv)
+{
+	u8 buffer[256];
+	int i, ret;
+
+	/* set up RAM ECC - enable interrupts sets it as well */
+	ret = mcp25xxfd_ecc_enable_int(priv, false);
+	if (ret)
+		return ret;
+
+	/* and clear SRAM so that no reads fails from now on */
+	memset(buffer, 0, sizeof(buffer));
+	for (i = 0; i < MCP25XXFD_SRAM_SIZE; i += sizeof(buffer)) {
+		ret = mcp25xxfd_cmd_writen(priv->spi, MCP25XXFD_SRAM_ADDR(i),
+					   buffer, sizeof(buffer));
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}