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can: mcp251x: mcp251x_hw_reset(): allow more time after a reset

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Some boards take longer than 5ms to power up after a reset, so allow
some retries attempts before giving up.

Fixes: ff06d611a3 ("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>
This commit is contained in:
Marc Kleine-Budde 2019-08-13 16:01:02 +02:00
parent af669cd26e
commit d84ea2123f
1 changed files with 13 additions and 4 deletions
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17
drivers/net/can/spi/mcp251x.c
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@ -606,7 +606,7 @@ static int mcp251x_setup(struct net_device *net, struct spi_device *spi)
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 */
@ -620,10 +620,19 @@ 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;
}