diff options
| author | Marc Kleine-Budde <mkl@pengutronix.de> | 2019-08-13 16:01:02 +0200 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2019-10-17 13:42:05 -0700 |
| commit | 35f63f5172c0b26127099613e90d024e7acd5210 (patch) | |
| tree | 7e497828dee050d257872e7712a77be28047c09b | |
| parent | 0e31027173296fb2f624b2ca9e903be5c23fdd64 (diff) | |
| download | linux-rt-35f63f5172c0b26127099613e90d024e7acd5210.tar.gz | |
can: mcp251x: mcp251x_hw_reset(): allow more time after a reset
commit d84ea2123f8d27144e3f4d58cd88c9c6ddc799de upstream.
Some boards take longer than 5ms to power up after a reset, so allow
some retries attempts before giving up.
Fixes: ff06d611a31c ("can: mcp251x: Improve mcp251x_hw_reset()")
Cc: linux-stable <stable@vger.kernel.org>
Tested-by: Sean Nyekjaer <sean@geanix.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
| -rw-r--r-- | drivers/net/can/spi/mcp251x.c | 19 |
1 files changed, 14 insertions, 5 deletions
diff --git a/drivers/net/can/spi/mcp251x.c b/drivers/net/can/spi/mcp251x.c index d8c448beab24..ec0b3d025867 100644 --- a/drivers/net/can/spi/mcp251x.c +++ b/drivers/net/can/spi/mcp251x.c @@ -627,7 +627,7 @@ static int mcp251x_setup(struct net_device *net, struct mcp251x_priv *priv, static int mcp251x_hw_reset(struct spi_device *spi) { struct mcp251x_priv *priv = spi_get_drvdata(spi); - u8 reg; + unsigned long timeout; int ret; /* Wait for oscillator startup timer after power up */ @@ -641,10 +641,19 @@ static int mcp251x_hw_reset(struct spi_device *spi) /* Wait for oscillator startup timer after reset */ mdelay(MCP251X_OST_DELAY_MS); - reg = mcp251x_read_reg(spi, CANSTAT); - if ((reg & CANCTRL_REQOP_MASK) != CANCTRL_REQOP_CONF) - return -ENODEV; - + /* Wait for reset to finish */ + timeout = jiffies + HZ; + while ((mcp251x_read_reg(spi, CANSTAT) & CANCTRL_REQOP_MASK) != + CANCTRL_REQOP_CONF) { + usleep_range(MCP251X_OST_DELAY_MS * 1000, + MCP251X_OST_DELAY_MS * 1000 * 2); + + if (time_after(jiffies, timeout)) { + dev_err(&spi->dev, + "MCP251x didn't enter in conf mode after reset\n"); + return -EBUSY; + } + } return 0; } |