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authorMarc Kleine-Budde <mkl@pengutronix.de>2019-08-13 16:01:02 +0200
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2019-10-17 13:42:05 -0700
commit35f63f5172c0b26127099613e90d024e7acd5210 (patch)
tree7e497828dee050d257872e7712a77be28047c09b /drivers/net/can/spi
parent0e31027173296fb2f624b2ca9e903be5c23fdd64 (diff)
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>
Diffstat (limited to 'drivers/net/can/spi')
-rw-r--r--drivers/net/can/spi/mcp251x.c19
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;
}