cg2900: Register CG2900 as clock source for wlan

This patch registers CG2900 Driver as clock source which can be
used by CW1200 Driver for enabling, disabling clock supplied by
CG2900.

ST-Ericsson Linux next: 361990
ST-Ericsson ID: 361990
ST-Ericsson FOSS-OUT ID: STETL-FOSS-OUT-10019

Change-Id: I0cd529823200c6225b13b36fa6bbeff337bd5e04
Signed-off-by: Hemant Gupta <hemant.gupta@stericsson.com>
Reviewed-on: http://gerrit.lud.stericsson.com/gerrit/33936
Reviewed-by: Nitin DHINGRA <nitin.dhingra@stericsson.com>
Reviewed-by: QABUILD
Reviewed-by: Lukasz RYMANOWSKI <lukasz.rymanowski@stericsson.com>
Reviewed-by: Linus WALLEIJ <linus.walleij@stericsson.com>
Reviewed-by: Dmitry TARNYAGIN <dmitry.tarnyagin@stericsson.com>
Tested-by: Bartosz MARKOWSKI <bartosz.markowski@tieto.com>

2 files changed, 148 insertions, 1 deletions

diff --git a/drivers/staging/cg2900/Makefile b/drivers/staging/cg2900/Makefile
index b1d0af41230..14e2847bacf 100644
--- a/drivers/staging/cg2900/Makefile
+++ b/drivers/staging/cg2900/Makefile
@@ -8,7 +8,8 @@ ccflags-y :=					\
 
 obj-$(CONFIG_CG2900)	+= devices-cg2900.o \
 				devices-cg2900-ux500.o \
-				board-ux500-cg2900.o
+				board-ux500-cg2900.o \
+				clock-cg2900.o
 
 obj-y				+= mfd/
 obj-y				+= bluetooth/
diff --git a/drivers/staging/cg2900/clock-cg2900.c b/drivers/staging/cg2900/clock-cg2900.c
new file mode 100755
index 00000000000..e504810a366
--- /dev/null
+++ b/drivers/staging/cg2900/clock-cg2900.c
@@ -0,0 +1,146 @@
+/*
+ * Copyright (C) ST-Ericsson SA 2011
+ *
+ * Author: Hemant Gupta <hemant.gupta@stericsson.com>
+ * Author: Tomasz Hliwiak <tomasz.hliwiak@tieto.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2, as
+ * published by the Free Software Foundation.
+ *
+ */
+
+#include <asm/mach-types.h>
+#include <linux/clk.h>
+#include <linux/clkdev.h>
+#include <linux/errno.h>
+#include <linux/kernel.h>
+#include <linux/mutex.h>
+#include <linux/platform_device.h>
+#include <linux/skbuff.h>
+#include "clock.h"
+#include "cg2900.h"
+
+static DEFINE_MUTEX(cg2900_clk_mutex);
+
+static struct cg2900_user_data *pf_data;
+static struct clk_lookup *cg2900_clk_lookup;
+
+/**
+ * cg2900_clk_enable() - Enables CG2900 Clock
+ *
+ * Enables CG2900 Clock by starting CG2900.
+ *
+ * Returns:
+ *  0 if success.
+ *  -EINVAL if stored pf_data is NULL.
+ *  Error codes generated by open.
+ */
+
+static int cg2900_clk_enable(struct clk *clk)
+{
+	int err = -EINVAL;
+	if (pf_data)
+		err = pf_data->open(pf_data);
+
+	return err;
+}
+
+/**
+ * cg2900_clk_disable() - Disables CG2900 Clock
+ *
+ * Disables CG2900 Clock by switching off CG2900.
+ */
+static void cg2900_clk_disable(struct clk *clk)
+{
+	if (pf_data)
+		pf_data->close(pf_data);
+}
+
+static struct clkops cg2900_clk_ops = {
+	.enable  = cg2900_clk_enable,
+	.disable = cg2900_clk_disable,
+};
+
+static struct clk cg2900_clk = {
+	.name	= "cg2900_clk",
+	.ops	= &cg2900_clk_ops,
+	.mutex	= &cg2900_clk_mutex,
+};
+
+/**
+ * cg2900_read_cb() - Dummy callback for cg2900 core read.
+ *
+ * Function is required by cg2900_core->open().
+ */
+static void cg2900_read_cb(struct cg2900_user_data *user, struct sk_buff *skb)
+{
+	kfree_skb(skb);
+}
+
+/**
+ * cg2900_core_probe() - Initialize resources.
+ *
+ * Function initializes pf_data structure and also adds the cg2900
+ * clock source.
+ */
+static int __devinit cg2900_core_probe(struct platform_device *pdev)
+{
+	cg2900_clk_lookup = clkdev_alloc(&cg2900_clk, "sys_clk_out",
+			"cw1200_wlan");
+
+	if (!cg2900_clk_lookup)
+		return -ENOMEM;
+
+	clkdev_add(cg2900_clk_lookup);
+	pf_data = dev_get_platdata(&pdev->dev);
+	pf_data->dev = &pdev->dev;
+	pf_data->read_cb = cg2900_read_cb;
+
+	return 0;
+}
+
+/**
+ * cg2900_core_remove() - Clean resources.
+ *
+ * Function cleans pf_data structure and removes the clock source.
+ */
+static int __devexit cg2900_core_remove(struct platform_device *pdev)
+{
+	clkdev_drop(cg2900_clk_lookup);
+	pf_data = NULL;
+
+	return 0;
+}
+
+static struct platform_driver cg2900_core_ctrl_driver = {
+	.driver = {
+		.name      = "cg2900-core",
+		.owner     = THIS_MODULE,
+	},
+	.probe     = cg2900_core_probe,
+	.remove    = __devexit_p(cg2900_core_remove),
+};
+
+/**
+ * clock_cg2900_init() - Register Platform Driver
+ *
+ * Registers the platform Driver.
+ */
+static int __init clock_cg2900_init(void)
+{
+	return platform_driver_register(&cg2900_core_ctrl_driver);
+}
+
+/**
+ * clock_cg2900_exit() - Unregister Platform Driver
+ *
+ * Unregister Platform Driver
+ */
+static void __exit clock_cg2900_exit(void)
+{
+	platform_driver_unregister(&cg2900_core_ctrl_driver);
+}
+
+module_init(clock_cg2900_init);
+module_exit(clock_cg2900_exit);