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authorHeikki Krogerus <heikki.krogerus@linux.intel.com>2015-09-21 11:17:30 (GMT)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2015-10-04 17:38:45 (GMT)
commit1edb3cf21f4b0be2a5d9577d4913eb9a3131cd16 (patch)
tree83927d70e55dcb24d17b8982fcfccef13cdddee0 /drivers/tty/serial/8250
parentc73942e22aa4a3d910f9be8d48de4080c3a52086 (diff)
downloadlinux-1edb3cf21f4b0be2a5d9577d4913eb9a3131cd16.tar.xz
serial: 8250_dw: rename and comment the fallback dma filter
Adding comment where the purpose of the function is explained. The dma parameters are not used, so removing them, and also moving the assignment of the function to the same place where the other dw8250_data structures members are being set in dw8250_probe. Signed-off-by: Heikki Krogerus <heikki.krogerus@linux.intel.com> Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/serial/8250')
-rw-r--r--drivers/tty/serial/8250/8250_dw.c15
1 files changed, 10 insertions, 5 deletions
diff --git a/drivers/tty/serial/8250/8250_dw.c b/drivers/tty/serial/8250/8250_dw.c
index 7ed0580..f4c5bd6 100644
--- a/drivers/tty/serial/8250/8250_dw.c
+++ b/drivers/tty/serial/8250/8250_dw.c
@@ -247,7 +247,15 @@ out:
serial8250_do_set_termios(p, termios, old);
}
-static bool dw8250_dma_filter(struct dma_chan *chan, void *param)
+/*
+ * dw8250_fallback_dma_filter will prevent the UART from getting just any free
+ * channel on platforms that have DMA engines, but don't have any channels
+ * assigned to the UART.
+ *
+ * REVISIT: This is a work around for limitation in the DMA Engine API. Once the
+ * core problem is fixed, this function is no longer needed.
+ */
+static bool dw8250_fallback_dma_filter(struct dma_chan *chan, void *param)
{
return false;
}
@@ -374,6 +382,7 @@ static int dw8250_probe(struct platform_device *pdev)
if (!data)
return -ENOMEM;
+ data->dma.fn = dw8250_fallback_dma_filter;
data->usr_reg = DW_UART_USR;
p->private_data = data;
@@ -460,10 +469,6 @@ static int dw8250_probe(struct platform_device *pdev)
if (!IS_ERR(data->rst))
reset_control_deassert(data->rst);
- data->dma.rx_param = data;
- data->dma.tx_param = data;
- data->dma.fn = dw8250_dma_filter;
-
dw8250_quirks(p, data);
/* If the Busy Functionality is not implemented, don't handle it */