diff options
author | Sascha Hauer <s.hauer@pengutronix.de> | 2010-09-28 09:53:35 +0200 |
---|---|---|
committer | Marc Kleine-Budde <mkl@pengutronix.de> | 2010-10-18 11:19:42 +0200 |
commit | f3a3ed3115d39463dc6672454bfbeaff46811a37 (patch) | |
tree | e4b58494a3f9411c687998435d67699a1c690fac /drivers | |
parent | 711e4d6eccd72c57938228b8e0c29cb205527032 (diff) |
can: mcp251x: allow to read two registers in one spi transfer
This patch bases on work done earlier by David Jander.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Acked-by: David Jander <david@protonic.nl>
Signed-off-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Wolfgang Grandegger <wg@grandegger.com>
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/net/can/mcp251x.c | 20 |
1 files changed, 17 insertions, 3 deletions
diff --git a/drivers/net/can/mcp251x.c b/drivers/net/can/mcp251x.c index fdea752f398..9b3466aed06 100644 --- a/drivers/net/can/mcp251x.c +++ b/drivers/net/can/mcp251x.c @@ -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 */ |