From mboxrd@z Thu Jan  1 00:00:00 1970
From: hechtb@gmail.com (Bastian Hecht)
Date: Wed,  6 Mar 2013 12:30:35 +0100
Subject: [PATCH v6 1/3] serial: sh-sci: Add OF support
Message-ID: <1362569437-11133-1-git-send-email-hechtb+renesas@gmail.com>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

We add the capabilty to probe Renesas SCI devices using Device Tree setup.

Signed-off-by: Bastian Hecht <hechtb+renesas@gmail.com>
Reviewed-by: Paul Mundt <lethal@linux-sh.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
---
v6:
putting it all together: I posted v5 as an incremental patch - here
the full version based on Simon Horman's tree topic/intc-of.

I will post another incremental version as well.

- rename sci at xxxxxxxx to serial at xxxxxxxx
- stick to scbrr-algorithm

 .../bindings/tty/serial/renesas,sci-serial.txt     |   47 +++++++
 drivers/tty/serial/sh-sci.c                        |  146 +++++++++++++++++++-
 include/linux/serial_sci.h                         |    4 +
 3 files changed, 193 insertions(+), 4 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/tty/serial/renesas,sci-serial.txt

diff --git a/Documentation/devicetree/bindings/tty/serial/renesas,sci-serial.txt b/Documentation/devicetree/bindings/tty/serial/renesas,sci-serial.txt
new file mode 100644
index 0000000..d80039e
--- /dev/null
+++ b/Documentation/devicetree/bindings/tty/serial/renesas,sci-serial.txt
@@ -0,0 +1,47 @@
+* Renesas SH-Mobile Serial Communication Interface
+
+Required properties:
+- compatible : Should be "renesas,sci-<port type>-uart", where <port type> is
+  "sci", "scif", "irda", "scifa", "scifb"
+  or for legacy devices
+  "sh2_scif_fifodata", "sh3_scif", "sh4_scif", "sh4_scif_no_scsptr",
+  "sh4_scif_fifodata", "sh7705_scif".
+- reg : Address and length of the register set for the device
+- interrupts : Should contain the following IRQs in this order:
+	ERI: receive-error interrupt
+	RXI: receive-FIFO-data-full interrupt
+	TXI: transmit-FIFO-data-empty interrupt
+	BRI: break reception interrupt
+- interrupt-names: The IRQ names "eri", "rxi", "txi" and "bri".
+- cell-index : The device id.
+- renesas,scscr : Should contain a bitfield used by the Serial Control Register.
+  b7 = SCSCR_TIE
+  b6 = SCSCR_RIE
+  b5 = SCSCR_TE
+  b4 = SCSCR_RE
+  b3 = SCSCR_REIE
+  b2 = SCSCR_TOIE
+  b1 = SCSCR_CKE1
+  b0 = SCSCR_CKE0
+- renesas,scbrr-algorithm : Choose an algorithm ID for the baud rate generator.
+  1 = SCBRR_ALGO_1 ((clk + 16 * bps) / (16 * bps) - 1)
+  2 = SCBRR_ALGO_2 ((clk + 16 * bps) / (32 * bps) - 1)
+  3 = SCBRR_ALGO_3 (((clk * 2) + 16 * bps) / (16 * bps) - 1)
+  4 = SCBRR_ALGO_4 (((clk * 2) + 16 * bps) / (32 * bps) - 1)
+  5 = SCBRR_ALGO_5 (((clk * 1000 / 32) / bps) - 1)
+
+Optional properties:
+- renesas,autoconf : Set if device is capable of auto configuration.
+
+Example:
+	serial at e6c50000 {
+		compatible = "renesas,sci-scifa-uart";
+		interrupt-parent = <&intca>;
+		reg = <0xe6c50000 0x100>;
+		interrupts = <0x0c20>, <0x0c20>, <0x0c20>, <0x0c20>;
+		interrupt-names = "eri", "rxi", "txi", "bri";
+		cell-index = <1>;
+		renesas,scscr = <0x30>;
+		renesas,scbrr-algorithm = <4>;
+		renesas,autoconf;
+	};
diff --git a/drivers/tty/serial/sh-sci.c b/drivers/tty/serial/sh-sci.c
index 6147756..03bb740 100644
--- a/drivers/tty/serial/sh-sci.c
+++ b/drivers/tty/serial/sh-sci.c
@@ -52,6 +52,7 @@
 #include <linux/scatterlist.h>
 #include <linux/slab.h>
 #include <linux/gpio.h>
+#include <linux/of.h>
 
 #ifdef CONFIG_SUPERH
 #include <asm/sh_bios.h>
@@ -2353,6 +2354,131 @@ static int sci_remove(struct platform_device *dev)
 	return 0;
 }
 
+static const struct of_device_id of_sci_match[] = {
+	{ .compatible = "renesas,sci-sci-uart",
+		.data = (void *)SCIx_SCI_REGTYPE },
+	{ .compatible = "renesas,sci-scif-uart",
+		.data = (void *)SCIx_SH4_SCIF_REGTYPE, },
+	{ .compatible = "renesas,sci-irda-uart",
+		.data = (void *)SCIx_IRDA_REGTYPE },
+	{ .compatible = "renesas,sci-scifa-uart",
+		.data = (void *)SCIx_SCIFA_REGTYPE },
+	{ .compatible = "renesas,sci-scifb-uart",
+		.data = (void *)SCIx_SCIFB_REGTYPE },
+	{ .compatible = "renesas,sci-sh2_scif_fifodata-uart",
+		.data = (void *)SCIx_SH2_SCIF_FIFODATA_REGTYPE },
+	{ .compatible = "renesas,sci-sh3_scif-uart",
+		.data = (void *)SCIx_SH3_SCIF_REGTYPE },
+	{ .compatible = "renesas,sci-sh4_scif-uart",
+		.data = (void *)SCIx_SH4_SCIF_REGTYPE },
+	{ .compatible = "renesas,sci-sh4_scif_no_scsptr-uart",
+		.data = (void *)SCIx_SH4_SCIF_NO_SCSPTR_REGTYPE },
+	{ .compatible = "renesas,sci-sh4_scif_fifodata-uart",
+		.data = (void *)SCIx_SH4_SCIF_FIFODATA_REGTYPE },
+	{ .compatible = "renesas,sci-sh7705_scif-uart",
+		.data = (void *)SCIx_SH7705_SCIF_REGTYPE },
+	{},
+};
+MODULE_DEVICE_TABLE(of, of_sci_match);
+
+static struct plat_sci_port *sci_parse_dt(struct platform_device *pdev,
+								int *dev_id)
+{
+	struct plat_sci_port *p;
+	struct device_node *np = pdev->dev.of_node;
+	const struct of_device_id *match;
+	struct resource *res;
+	const __be32 *prop;
+	int i, irq, val;
+
+	if (!IS_ENABLED(CONFIG_OF) || !np)
+		return NULL;
+
+	match = of_match_node(of_sci_match, pdev->dev.of_node);
+	if (!match || !match->data) {
+		dev_err(&pdev->dev, "OF match error\n");
+		return NULL;
+	}
+
+	p = devm_kzalloc(&pdev->dev, sizeof(struct plat_sci_port), GFP_KERNEL);
+	if (!p) {
+		dev_err(&pdev->dev, "failed to allocate DT config data\n");
+		return NULL;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (!res) {
+		dev_err(&pdev->dev, "failed to get I/O memory\n");
+		return NULL;
+	}
+	p->mapbase = res->start;
+
+	for (i = 0; i < SCIx_NR_IRQS; i++) {
+		irq = platform_get_irq(pdev, i);
+		if (irq < 0) {
+			dev_err(&pdev->dev, "failed to get irq data %d\n", i);
+			return NULL;
+		}
+		p->irqs[i] = irq;
+	}
+
+	prop = of_get_property(np, "cell-index", NULL);
+	if (!prop) {
+		dev_err(&pdev->dev, "required DT prop cell-index missing\n");
+		return NULL;
+	}
+	*dev_id = be32_to_cpup(prop);
+
+	prop = of_get_property(np, "renesas,scscr", NULL);
+	if (!prop) {
+		dev_err(&pdev->dev, "required DT prop scscr missing\n");
+		return NULL;
+	}
+	p->scscr = be32_to_cpup(prop);
+
+	prop = of_get_property(np, "renesas,scbrr-algorithm", NULL);
+	if (!prop) {
+		dev_err(&pdev->dev, "required DT prop scbrr-algorithm missing\n");
+		return NULL;
+	}
+	val = be32_to_cpup(prop);
+	if (val <= SCBRR_ALGO_INVALID || val >= SCBRR_NR_ALGOS) {
+		dev_err(&pdev->dev, "DT prop clock-algorithm out of range\n");
+		return NULL;
+	}
+	p->scbrr_algo_id = val;
+
+	p->flags = UPF_IOREMAP;
+	if (of_get_property(np, "renesas,autoconf", NULL))
+		p->flags |= UPF_BOOT_AUTOCONF;
+
+	p->regtype = (unsigned int)match->data;
+
+	switch (p->regtype) {
+	case SCIx_SCI_REGTYPE:
+		p->type = PORT_SCI;
+		break;
+	case SCIx_SH4_SCIF_REGTYPE:
+		p->type = PORT_SCIF;
+		break;
+	case SCIx_IRDA_REGTYPE:
+		p->type = PORT_IRDA;
+		break;
+	case SCIx_SCIFA_REGTYPE:
+		p->type = PORT_SCIFA;
+		break;
+	case SCIx_SCIFB_REGTYPE:
+		p->type = PORT_SCIFB;
+		break;
+	default:
+		/* legacy register sets default to PORT_SCIF */
+		p->type = PORT_SCIF;
+		break;
+	}
+
+	return p;
+}
+
 static int sci_probe_single(struct platform_device *dev,
 				      unsigned int index,
 				      struct plat_sci_port *p,
@@ -2385,9 +2511,9 @@ static int sci_probe_single(struct platform_device *dev,
 
 static int sci_probe(struct platform_device *dev)
 {
-	struct plat_sci_port *p = dev->dev.platform_data;
-	struct sci_port *sp = &sci_ports[dev->id];
-	int ret;
+	struct plat_sci_port *p;
+	struct sci_port *sp;
+	int ret, dev_id = dev->id;
 
 	/*
 	 * If we've come here via earlyprintk initialization, head off to
@@ -2397,9 +2523,20 @@ static int sci_probe(struct platform_device *dev)
 	if (is_early_platform_device(dev))
 		return sci_probe_earlyprintk(dev);
 
+	if (dev->dev.of_node)
+		p = sci_parse_dt(dev, &dev_id);
+	else
+		p = dev->dev.platform_data;
+
+	if (!p) {
+		dev_err(&dev->dev, "no setup data supplied\n");
+		return -EINVAL;
+	}
+
+	sp = &sci_ports[dev_id];
 	platform_set_drvdata(dev, sp);
 
-	ret = sci_probe_single(dev, dev->id, p, sp);
+	ret = sci_probe_single(dev, dev_id, p, sp);
 	if (ret)
 		return ret;
 
@@ -2451,6 +2588,7 @@ static struct platform_driver sci_driver = {
 		.name	= "sh-sci",
 		.owner	= THIS_MODULE,
 		.pm	= &sci_dev_pm_ops,
+		.of_match_table = of_match_ptr(of_sci_match),
 	},
 };
 
diff --git a/include/linux/serial_sci.h b/include/linux/serial_sci.h
index eb763ad..857eec4 100644
--- a/include/linux/serial_sci.h
+++ b/include/linux/serial_sci.h
@@ -11,11 +11,15 @@
 #define SCIx_NOT_SUPPORTED	(-1)
 
 enum {
+	SCBRR_ALGO_INVALID,
+
 	SCBRR_ALGO_1,		/* ((clk + 16 * bps) / (16 * bps) - 1) */
 	SCBRR_ALGO_2,		/* ((clk + 16 * bps) / (32 * bps) - 1) */
 	SCBRR_ALGO_3,		/* (((clk * 2) + 16 * bps) / (16 * bps) - 1) */
 	SCBRR_ALGO_4,		/* (((clk * 2) + 16 * bps) / (32 * bps) - 1) */
 	SCBRR_ALGO_5,		/* (((clk * 1000 / 32) / bps) - 1) */
+
+	SCBRR_NR_ALGOS,
 };
 
 #define SCSCR_TIE	(1 << 7)
-- 
1.7.9.5