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authorLars-Peter Clausen <lars@metafoo.de>2010-06-19 04:08:16 +0000
committerRalf Baechle <ralf@linux-mips.org>2010-08-05 13:26:16 +0100
commitc3b9566de89f40557e3a3d041ca08b05978aeb12 (patch)
treeabaf7ae9c47236131fa6e3e387bd369d6d27a485 /arch
parenteda0347bf8b449a42b3bf4e0b9754263d853982f (diff)
downloadblackbird-op-linux-c3b9566de89f40557e3a3d041ca08b05978aeb12.tar.gz
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MIPS: JZ4740: Add serial support
The JZ4740 UART interface is almost 16550 compatible. The UART module needs to be enabled by setting a bit in the FCR register and it has support for receive timeout interrupts. Instead of adding yet another machine specific quirk to the 8250 serial driver we provide a serial_out implementation which sets the required additional flags. Signed-off-by: Lars-Peter Clausen <lars@metafoo.de> Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/1403/ Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Diffstat (limited to 'arch')
-rw-r--r--arch/mips/jz4740/serial.c33
-rw-r--r--arch/mips/jz4740/serial.h20
2 files changed, 53 insertions, 0 deletions
diff --git a/arch/mips/jz4740/serial.c b/arch/mips/jz4740/serial.c
new file mode 100644
index 000000000000..d23de45826d1
--- /dev/null
+++ b/arch/mips/jz4740/serial.c
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
+ * JZ4740 serial support
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#include <linux/io.h>
+#include <linux/serial_core.h>
+#include <linux/serial_reg.h>
+
+void jz4740_serial_out(struct uart_port *p, int offset, int value)
+{
+ switch (offset) {
+ case UART_FCR:
+ value |= 0x10; /* Enable uart module */
+ break;
+ case UART_IER:
+ value |= (value & 0x4) << 2;
+ break;
+ default:
+ break;
+ }
+ writeb(value, p->membase + (offset << p->regshift));
+}
diff --git a/arch/mips/jz4740/serial.h b/arch/mips/jz4740/serial.h
new file mode 100644
index 000000000000..b9fe3ade0289
--- /dev/null
+++ b/arch/mips/jz4740/serial.h
@@ -0,0 +1,20 @@
+/*
+ * Copyright (C) 2010, Lars-Peter Clausen <lars@metafoo.de>
+ * JZ4740 serial support
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2 of the License, or (at your
+ * option) any later version.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ */
+
+#ifndef __MIPS_JZ4740_SERIAL_H__
+
+void jz4740_serial_out(struct uart_port *p, int offset, int value);
+
+#endif
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