Commit f3a3ed31 authored by Sascha Hauer's avatar Sascha Hauer Committed by Marc Kleine-Budde
Browse files

can: mcp251x: allow to read two registers in one spi transfer 



This patch bases on work done earlier by David Jander.

Signed-off-by: default avatarSascha Hauer <s.hauer@pengutronix.de>
Acked-by: default avatarDavid Jander <david@protonic.nl>
Signed-off-by: default avatarUwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: default avatarMarc Kleine-Budde <mkl@pengutronix.de>
Acked-by: default avatarWolfgang Grandegger <wg@grandegger.com>
parent 711e4d6e

drivers/net/can/mcp251x.c

+17 −3
Original line number Diff line number Diff line
@@ -319,6 +319,20 @@ static u8 mcp251x_read_reg(struct spi_device *spi, uint8_t reg) 
	return val;

}



static void mcp251x_read_2regs(struct spi_device *spi, uint8_t reg,

		uint8_t *v1, uint8_t *v2)

{

	struct mcp251x_priv *priv = dev_get_drvdata(&spi->dev);



	priv->spi_tx_buf[0] = INSTRUCTION_READ;

	priv->spi_tx_buf[1] = reg;



	mcp251x_spi_trans(spi, 4);



	*v1 = priv->spi_rx_buf[2];

	*v2 = priv->spi_rx_buf[3];

}



static void mcp251x_write_reg(struct spi_device *spi, u8 reg, uint8_t val)

{

	struct mcp251x_priv *priv = dev_get_drvdata(&spi->dev);
@@ -754,10 +768,11 @@ static irqreturn_t mcp251x_can_ist(int irq, void *dev_id) 
	mutex_lock(&priv->mcp_lock);

	while (!priv->force_quit) {

		enum can_state new_state;

		u8 intf = mcp251x_read_reg(spi, CANINTF);

		u8 eflag;

		u8 intf, eflag;

		int can_id = 0, data1 = 0;



		mcp251x_read_2regs(spi, CANINTF, &intf, &eflag);



		if (intf & CANINTF_RX0IF) {

			mcp251x_hw_rx(spi, 0);

			/* Free one buffer ASAP */
@@ -770,7 +785,6 @@ static irqreturn_t mcp251x_can_ist(int irq, void *dev_id) 


		mcp251x_write_bits(spi, CANINTF, intf, 0x00);



		eflag = mcp251x_read_reg(spi, EFLG);

		mcp251x_write_reg(spi, EFLG, 0x00);



		/* Update can state */