[PATCH 3/5] tty/serial: at91: fix error handling in atmel_serial_probe()

From: Cyrille Pitchen
Date: Tue Dec 09 2014 - 08:32:30 EST


-EDEFER error wasn't handle properly by atmel_serial_probe().
As an example, when atmel_serial_probe() is called for the first time, we pass
the test_and_set_bit() test to check whether the port has already been
initalized. Then we call atmel_init_port(), which may return -EDEFER, possibly
returned before by clk_get(). Consequently atmel_serial_probe() used to return
this error code WITHOUT clearing the port bit in the "atmel_ports_in_use" mask.
When atmel_serial_probe() was called for the second time, it used to fail on
the test_and_set_bit() function then returning -EBUSY.

When atmel_serial_probe() fails, this patch make it clear the port bit in the
"atmel_ports_in_use" mask, if needed, before returning the error code.

Signed-off-by: Cyrille Pitchen <cyrille.pitchen@xxxxxxxxx>
---
drivers/tty/serial/atmel_serial.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c
index c6621dc..92a8b26 100644
--- a/drivers/tty/serial/atmel_serial.c
+++ b/drivers/tty/serial/atmel_serial.c
@@ -2565,7 +2565,7 @@ static int atmel_serial_probe(struct platform_device *pdev)

ret = atmel_init_port(port, pdev);
if (ret)
- goto err;
+ goto err_clear_bit;

if (!atmel_use_pdc_rx(&port->uart)) {
ret = -ENOMEM;
@@ -2628,6 +2628,8 @@ err_alloc_ring:
clk_put(port->clk);
port->clk = NULL;
}
+err_clear_bit:
+ clear_bit(port->uart.line, atmel_ports_in_use);
err:
return ret;
}
--
1.8.2.2

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