Hi Matthias,

2015-05-19 17:22 GMT+09:00 Matthias Brugger [off-list ref]:

2015-05-19 3:11 GMT+02:00 Masahiro Yamada [off-list ref]:

quoted

Add the driver for on-chip UART used on UniPhier SoCs.

This hardware is similar to 8250 with a slightly different register
mapping, so it should go into drivers/tty/serial/8250 directory.

The patch is for a driver in this folder, so no need to but it in the
commit message.
Instead just write a short description about the difference to a
standard 8250 device.

quoted

Signed-off-by: Masahiro Yamada <redacted>
---

Changes in v3:
  - Just add *_SHIFT macro for the special case

Changes in v2:
  - Drop unnecessary #include <linux/init.h>
  - Sort includes in alphabetical order
  - Use devm_clk_get() rather than of_clk_get()
  - Delete unneeded clk_put() from uniphier_uart_remove callback
  - Delete unneeded IS_ERR_OR_NULL check from uniphier_uart_remove callback
  - Use UNIPHIER_UART_*_SHIFT instead of hard-coded shift values
  - Change the first argument type of uniphier_of_serial_setup()
    from (struct platform_device *) to (struct device *) for code-cleanup.

 drivers/tty/serial/8250/8250_uniphier.c | 237 ++++++++++++++++++++++++++++++++
 drivers/tty/serial/8250/Kconfig         |   7 +
 drivers/tty/serial/8250/Makefile        |   1 +
 3 files changed, 245 insertions(+)
 create mode 100644 drivers/tty/serial/8250/8250_uniphier.c

diff --git a/drivers/tty/serial/8250/8250_uniphier.c b/drivers/tty/serial/8250/8250_uniphier.c
new file mode 100644
index 0000000..50349bf
--- /dev/null
+++ b/drivers/tty/serial/8250/8250_uniphier.c

@@ -0,0 +1,237 @@
+/*
+ * Copyright (C) 2015 Masahiro Yamada <yamada.masahiro@socionext.com>
+ *
+ * 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.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/serial_8250.h>
+#include <linux/serial_core.h>
+#include <linux/serial_reg.h>
+#include "8250.h"
+
+/* Most (but not all) of UniPhier UART devices have 64-depth FIFO. */
+#define UNIPHIER_UART_DEFAULT_FIFO_SIZE        64
+
+#define UNIPHIER_UART_CHAR_FCR 3       /* Character / FIFO Control Register */
+#define UNIPHIER_UART_LCR_MCR  4       /* Line/Modem Control Register */
+#define     UNIPHIER_UART_LCR_SHIFT    8
+#define UNIPHIER_UART_DLR      9       /* Divisor Latch Register */

Nit pick: Please fix identation. After "define" just put one blank.
I personally prefer that the define values are aligned by tabs, but
that's up tu you.

I intentionally use deeper indentation for *_SHIFT
because I want to clearly show  UNIPHIER_UART_LCR_SHIFT
belongs to UNIPHIER_UART_LCR_MCR register.

I also want to describe them within 80 columns including comments,
so I cannot insert extra TABs to align the values.

-- 
Best Regards
Masahiro Yamada