[PATCH 08/10] ARM: clps711x: Add CLPS711X cpuidle driver

[Alexander Shiyan]

This adds the cpuidle driver for Cirrus Logic CLPS711X series SoCs.
Designed primarily for migration CLPS711X subarch for multiplatform & DT.

Signed-off-by: Alexander Shiyan <shc_work at mail.ru>
---
 drivers/cpuidle/Kconfig            |  6 +++
 drivers/cpuidle/Makefile           |  1 +
 drivers/cpuidle/cpuidle-clps711x.c | 80 ++++++++++++++++++++++++++++++++++++++
 3 files changed, 87 insertions(+)
 create mode 100644 drivers/cpuidle/cpuidle-clps711x.c

diff --git a/drivers/cpuidle/Kconfig b/drivers/cpuidle/Kconfig
index 0e2cd5c..c68a0cf 100644
--- a/drivers/cpuidle/Kconfig
+++ b/drivers/cpuidle/Kconfig
@@ -36,6 +36,12 @@ config CPU_IDLE_CALXEDA
 	help
 	  Select this to enable cpuidle on Calxeda processors.
 
+config CPU_IDLE_CLPS711X
+	bool "CPU Idle Driver for CLPS711X processors"
+	depends on ARCH_CLPS711X
+	help
+	  Select this to enable cpuidle on Cirrus Logic CLPS711X processors.
+
 config CPU_IDLE_ZYNQ
 	bool "CPU Idle Driver for Xilinx Zynq processors"
 	depends on ARCH_ZYNQ
diff --git a/drivers/cpuidle/Makefile b/drivers/cpuidle/Makefile
index 8767a7b..d07d2cb 100644
--- a/drivers/cpuidle/Makefile
+++ b/drivers/cpuidle/Makefile
@@ -6,5 +6,6 @@ obj-y += cpuidle.o driver.o governor.o sysfs.o governors/
 obj-$(CONFIG_ARCH_NEEDS_CPU_IDLE_COUPLED) += coupled.o
 
 obj-$(CONFIG_CPU_IDLE_CALXEDA) += cpuidle-calxeda.o
+obj-$(CONFIG_CPU_IDLE_CLPS711X)	+= cpuidle-clps711x.o
 obj-$(CONFIG_ARCH_KIRKWOOD) += cpuidle-kirkwood.o
 obj-$(CONFIG_CPU_IDLE_ZYNQ) += cpuidle-zynq.o
diff --git a/drivers/cpuidle/cpuidle-clps711x.c b/drivers/cpuidle/cpuidle-clps711x.c
new file mode 100644
index 0000000..9f0129f
--- /dev/null
+++ b/drivers/cpuidle/cpuidle-clps711x.c
@@ -0,0 +1,80 @@
+/*
+ *  CLPS711X CPU idle driver
+ *
+ *  Copyright (C) 2013 Alexander Shiyan <shc_work at mail.ru>
+ *
+ * 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.
+ */
+
+#include <linux/cpuidle.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+
+static void __iomem *clps711x_halt;
+
+static int clps711x_cpuidle_halt(struct cpuidle_device *dev,
+				 struct cpuidle_driver *drv, int index)
+{
+	writel(1, clps711x_halt);
+	asm volatile ("mov r0, r0");
+	asm volatile ("mov r0, r0");
+
+	return index;
+}
+
+static struct cpuidle_driver clps711x_idle_driver = {
+	.name			= "clps711x_idle",
+	.owner			= THIS_MODULE,
+	.state_count		= 1,
+	.states[0]	= {
+		.name		= "HALT",
+		.desc		= "CLPS711X WFI",
+		.enter		= clps711x_cpuidle_halt,
+		.exit_latency	= 1,
+	},
+};
+
+static int __init clps711x_cpuidle_probe(struct platform_device *pdev)
+{
+	struct resource *res;
+
+	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	clps711x_halt = devm_ioremap_resource(&pdev->dev, res);
+	if (IS_ERR(clps711x_halt))
+		return PTR_ERR(clps711x_halt);
+
+	return cpuidle_register(&clps711x_idle_driver, NULL);
+}
+
+static int clps711x_cpuidle_remove(struct platform_device *pdev)
+{
+	cpuidle_unregister(&clps711x_idle_driver);
+
+	return 0;
+}
+
+static const struct of_device_id clps711x_cpuidle_dt_ids[] = {
+	{ .compatible = "cirrus,clps711x-cpuidle", },
+	{ }
+};
+MODULE_DEVICE_TABLE(of, clps711x_cpuidle_dt_ids);
+
+static struct platform_driver clps711x_cpuidle_driver = {
+	.driver	= {
+		.name		= "clps711x-cpuidle",
+		.owner		= THIS_MODULE,
+		.of_match_table	= clps711x_cpuidle_dt_ids,
+	},
+	.remove	= clps711x_cpuidle_remove,
+};
+module_platform_driver_probe(clps711x_cpuidle_driver, clps711x_cpuidle_probe);
+
+MODULE_AUTHOR("Alexander Shiyan <shc_work at mail.ru>");
+MODULE_DESCRIPTION("CLPS711X CPU idle driver");
+MODULE_LICENSE("GPL");
-- 
1.8.1.5