[PATCH v4 15/21] misc: support for LP-8x4x DIP switch

[Sergei Ianovich]

Signed-off-by: Sergei Ianovich <ynvich at gmail.com>
---
   v3..v4
   * move DTS binding to a different patch (8/21)

   v2..v3
   * new patch

 .../devicetree/bindings/misc/lp8x4x-bus.txt        |  2 ++
 Documentation/misc-devices/lp8x4x_bus.txt          |  3 +++
 drivers/misc/lp8x4x_bus.c                          | 26 ++++++++++++++++++++++
 3 files changed, 31 insertions(+)

diff --git a/Documentation/devicetree/bindings/misc/lp8x4x-bus.txt b/Documentation/devicetree/bindings/misc/lp8x4x-bus.txt
index 8a55020..1b1776a 100644
--- a/Documentation/devicetree/bindings/misc/lp8x4x-bus.txt
+++ b/Documentation/devicetree/bindings/misc/lp8x4x-bus.txt
@@ -7,6 +7,7 @@ Required properties:
 
 - reg: physical base addresses and region lengths of
        * the rotary switch
+       * the 8bit DIP switch
        * the slot count register
 
 Example:
@@ -14,5 +15,6 @@ Example:
 	backplane {
 		compatible = "icpdas,backplane-lp8x4x";
 		reg = <0x0 0x2
+		       0x9002 0x2
 		       0x9046 0x2>;
 	};
diff --git a/Documentation/misc-devices/lp8x4x_bus.txt b/Documentation/misc-devices/lp8x4x_bus.txt
index bea435b..829781b 100644
--- a/Documentation/misc-devices/lp8x4x_bus.txt
+++ b/Documentation/misc-devices/lp8x4x_bus.txt
@@ -26,6 +26,9 @@ SYSFS
 
 /sys/bus/icpdas/devices/backplane:
 
+dip
+	RO - shows status of LP-8x4x 8bit DIP switch
+
 rotary
 	RO - shows position of LP-8x4x rotary switch (0-9)
 
diff --git a/drivers/misc/lp8x4x_bus.c b/drivers/misc/lp8x4x_bus.c
index 18ca8f8..dfbc8c4 100644
--- a/drivers/misc/lp8x4x_bus.c
+++ b/drivers/misc/lp8x4x_bus.c
@@ -26,6 +26,7 @@ struct lp8x4x_master {
 	unsigned int		slot_count;
 	void			*count_addr;
 	void			*rotary_addr;
+	void			*dip_addr;
 	struct device		dev;
 };
 
@@ -67,9 +68,20 @@ static ssize_t rotary_show(struct device *dev,
 
 static DEVICE_ATTR_RO(rotary);
 
+static ssize_t dip_show(struct device *dev,
+		struct device_attribute *attr, char *buf)
+{
+	struct lp8x4x_master *m = container_of(dev, struct lp8x4x_master, dev);
+
+	return sprintf(buf, "0x%02x\n", ioread8(m->dip_addr) ^ 0xff);
+}
+
+static DEVICE_ATTR_RO(dip);
+
 static struct attribute *master_dev_attrs[] = {
 	&dev_attr_slot_count.attr,
 	&dev_attr_rotary.attr,
+	&dev_attr_dip.attr,
 	NULL,
 };
 ATTRIBUTE_GROUPS(master_dev);
@@ -118,6 +130,20 @@ static int __init lp8x4x_bus_probe(struct platform_device *pdev)
 
 	res = platform_get_resource(pdev, IORESOURCE_MEM, r++);
 	if (!res) {
+		dev_err(&pdev->dev, "Failed to get DIP switch address\n");
+		err = -ENODEV;
+		goto err_free;
+	}
+
+	m->dip_addr = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(m->dip_addr)) {
+		dev_err(&pdev->dev, "Failed to ioremap DIP switch address\n");
+		err = PTR_ERR(m->dip_addr);
+		goto err_free;
+	}
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, r++);
+	if (!res) {
 		dev_err(&pdev->dev, "could not get slot count address\n");
 		err = -ENODEV;
 		goto err_free;
-- 
1.8.4.2