Initial commit

target/linux/octeontx/patches-5.4/0003-can-mcp251x-convert-to-half-duplex-SPI.patch

@@ -0,0 +1,57 @@
+From 097cc81ee5c15913ad330baffff2e3dea09bdad0 Mon Sep 17 00:00:00 2001
+From: Tim Harvey <tharvey@gateworks.com>
+Date: Thu, 30 Aug 2018 15:16:08 -0700
+Subject: [PATCH] can: mcp251x: convert driver to half-duplex SPI
+
+Some SPI host controllers such as the Cavium Thunder TX do not support
+full-duplex SPI. Using half-duplex transfers allows the driver to work
+with those host controllers.
+
+Signed-off-by: Tim Harvey <tharvey@gateworks.com>
+---
+ drivers/net/can/spi/mcp251x.c | 15 ++++++++-------
+ 1 file changed, 8 insertions(+), 7 deletions(-)
+
+--- a/drivers/net/can/spi/mcp251x.c
++++ b/drivers/net/can/spi/mcp251x.c
+@@ -291,23 +291,23 @@ static u8 mcp251x_read_reg(struct spi_de
+ 	priv->spi_tx_buf[0] = INSTRUCTION_READ;
+ 	priv->spi_tx_buf[1] = reg;
+ 
+-	mcp251x_spi_trans(spi, 3);
+-	val = priv->spi_rx_buf[2];
++	spi_write_then_read(spi, priv->spi_tx_buf, 2, &val, 1);
+ 
+ 	return val;
+ }
+ 
+ static void mcp251x_read_2regs(struct spi_device *spi, u8 reg, u8 *v1, u8 *v2)
+ {
++	u8 val[4] = {0};
+ 	struct mcp251x_priv *priv = spi_get_drvdata(spi);
+ 
+ 	priv->spi_tx_buf[0] = INSTRUCTION_READ;
+ 	priv->spi_tx_buf[1] = reg;
+ 
+-	mcp251x_spi_trans(spi, 4);
++	spi_write_then_read(spi, priv->spi_tx_buf, 2, val, 2);
+ 
+-	*v1 = priv->spi_rx_buf[2];
+-	*v2 = priv->spi_rx_buf[3];
++	*v1 = val[0];
++	*v2 = val[1];
+ }
+ 
+ static void mcp251x_write_reg(struct spi_device *spi, u8 reg, u8 val)
+@@ -398,8 +398,9 @@ static void mcp251x_hw_rx_frame(struct s
+ 			buf[i] = mcp251x_read_reg(spi, RXBCTRL(buf_idx) + i);
+ 	} else {
+ 		priv->spi_tx_buf[RXBCTRL_OFF] = INSTRUCTION_READ_RXB(buf_idx);
+-		mcp251x_spi_trans(spi, SPI_TRANSFER_BUF_LEN);
+-		memcpy(buf, priv->spi_rx_buf, SPI_TRANSFER_BUF_LEN);
++		spi_write_then_read(spi, priv->spi_tx_buf, 1, priv->spi_rx_buf,
++				    SPI_TRANSFER_BUF_LEN);
++		memcpy(buf + 1, priv->spi_rx_buf, SPI_TRANSFER_BUF_LEN - 1);
+ 	}
+ }
+