cpufreq: add input-cfboost
Michal Pecio [Wed, 29 Aug 2012 23:40:28 +0000 (16:40 -0700)]
Add a module which can be used alongside any cpufreq governor to
temporarily raise CPU frequency upon input events.

Change-Id: Id0c69e5c7194c0e27ec176787cdc076b461d749e
Signed-off-by: Michal Pecio <mpecio@nvidia.com>
Reviewed-on: http://git-master/r/122180
Reviewed-by: Satya Popuri <spopuri@nvidia.com>
Reviewed-by: Diwakar Tundlam <dtundlam@nvidia.com>

drivers/input/Kconfig
drivers/input/Makefile
drivers/input/input-cfboost.c [new file with mode: 0644]

index 69d3686..f429ea3 100644 (file)
@@ -174,6 +174,16 @@ config INPUT_KEYRESET
          To compile this driver as a module, choose M here: the
          module will be called keyreset.
 
+config INPUT_CFBOOST
+       tristate "Input event CPU frequency booster"
+       depends on INPUT && CPU_FREQ
+       help
+         Say Y here if you want to temporarily boost CPU frequency upon input
+         events.
+
+         To compile this driver as a module, choose M here: the
+         module will be called input-cfboost.
+
 comment "Input Device Drivers"
 
 source "drivers/input/keyboard/Kconfig"
index 9a7cc41..416f676 100644 (file)
@@ -27,3 +27,5 @@ obj-$(CONFIG_INPUT_APMPOWER)  += apm-power.o
 obj-$(CONFIG_INPUT_KEYRESET)   += keyreset.o
 obj-$(CONFIG_INPUT_OF_MATRIX_KEYMAP) += of_keymap.o
 obj-$(CONFIG_INPUT_KEYRESET)   += keyreset.o
+
+obj-$(CONFIG_INPUT_CFBOOST)    += input-cfboost.o
diff --git a/drivers/input/input-cfboost.c b/drivers/input/input-cfboost.c
new file mode 100644 (file)
index 0000000..bef3ec5
--- /dev/null
@@ -0,0 +1,174 @@
+/*
+ * drivers/input/input-cfboost.c
+ *
+ * Copyright (C) 2012 NVIDIA Corporation
+ *
+ * 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; version 2 of the License.
+ *
+ * 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.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+ *
+ */
+
+#include <linux/slab.h>
+#include <linux/jiffies.h>
+#include <linux/printk.h>
+#include <linux/workqueue.h>
+#include <linux/input.h>
+#include <linux/module.h>
+#include <linux/pm_qos.h>
+
+/* This module listens to input events and sets a temporary frequency
+ * floor upon input event detection. This is based on changes to
+ * cpufreq ondemand governor by:
+ *
+ * Tero Kristo <tero.kristo@nokia.com>
+ * Brian Steuer <bsteuer@codeaurora.org>
+ * David Ng <dave@codeaurora.org>
+ *
+ * at git://codeaurora.org/kernel/msm.git tree, commits:
+ *
+ * 2a6181bc76c6ce46ca0fa8e547be42acd534cf0e
+ * 1cca8861d8fda4e05f6b0c59c60003345c15454d
+ * 96a9aeb02bf5b3fbbef47e44460750eb275e9f1b
+ * b600449501cf15928440f87eff86b1f32d14214e
+ * 88a65c7ae04632ffee11f9fc628d7ab017c06b83
+ */
+
+MODULE_AUTHOR("Antti P Miettinen <amiettinen@nvidia.com>");
+MODULE_DESCRIPTION("Input event CPU frequency booster");
+MODULE_LICENSE("GPL v2");
+
+
+static struct pm_qos_request qos_req;
+static struct work_struct boost;
+static struct delayed_work unboost;
+static unsigned int boost_freq; /* kHz */
+module_param(boost_freq, uint, 0644);
+static unsigned long boost_time = 500; /* ms */
+module_param(boost_time, ulong, 0644);
+static struct workqueue_struct *cfb_wq;
+
+static void cfb_boost(struct work_struct *w)
+{
+       cancel_delayed_work_sync(&unboost);
+       pm_qos_update_request(&qos_req, boost_freq);
+       queue_delayed_work(cfb_wq, &unboost, msecs_to_jiffies(boost_time));
+}
+
+static void cfb_unboost(struct work_struct *w)
+{
+       pm_qos_update_request(&qos_req, PM_QOS_DEFAULT_VALUE);
+}
+
+static void cfb_input_event(struct input_handle *handle, unsigned int type,
+                           unsigned int code, int value)
+{
+       if (!work_pending(&boost))
+               queue_work(cfb_wq, &boost);
+}
+
+static int cfb_input_connect(struct input_handler *handler,
+                            struct input_dev *dev,
+                            const struct input_device_id *id)
+{
+       struct input_handle *handle;
+       int error;
+
+       handle = kzalloc(sizeof(struct input_handle), GFP_KERNEL);
+       if (!handle)
+               return -ENOMEM;
+
+       handle->dev = dev;
+       handle->handler = handler;
+       handle->name = "icfboost";
+
+       error = input_register_handle(handle);
+       if (error)
+               goto err2;
+
+       error = input_open_device(handle);
+       if (error)
+               goto err1;
+
+       return 0;
+err1:
+       input_unregister_handle(handle);
+err2:
+       kfree(handle);
+       return error;
+}
+
+static void cfb_input_disconnect(struct input_handle *handle)
+{
+       input_close_device(handle);
+       input_unregister_handle(handle);
+       kfree(handle);
+}
+
+/* XXX make configurable */
+static const struct input_device_id cfb_ids[] = {
+       { /* touch screen */
+               .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
+                               INPUT_DEVICE_ID_MATCH_KEYBIT,
+               .evbit = { BIT_MASK(EV_ABS) },
+               .keybit = {[BIT_WORD(BTN_TOUCH)] = BIT_MASK(BTN_TOUCH) },
+       },
+       { /* mouse */
+               .flags = INPUT_DEVICE_ID_MATCH_EVBIT |
+                               INPUT_DEVICE_ID_MATCH_KEYBIT,
+               .evbit = { BIT_MASK(EV_REL) },
+               .keybit = {[BIT_WORD(BTN_MOUSE)] = BIT_MASK(BTN_MOUSE) },
+       },
+       { },
+};
+
+static struct input_handler cfb_input_handler = {
+       .event          = cfb_input_event,
+       .connect        = cfb_input_connect,
+       .disconnect     = cfb_input_disconnect,
+       .name           = "icfboost",
+       .id_table       = cfb_ids,
+};
+
+static int __init cfboost_init(void)
+{
+       int ret;
+
+       cfb_wq = create_workqueue("icfb-wq");
+       if (!cfb_wq)
+               return -ENOMEM;
+       INIT_WORK(&boost, cfb_boost);
+       INIT_DELAYED_WORK(&unboost, cfb_unboost);
+       ret = input_register_handler(&cfb_input_handler);
+       if (ret) {
+               destroy_workqueue(cfb_wq);
+               return ret;
+       }
+       pm_qos_add_request(&qos_req, PM_QOS_CPU_FREQ_MIN,
+                          PM_QOS_DEFAULT_VALUE);
+       return 0;
+}
+
+static void __exit cfboost_exit(void)
+{
+       /* stop input events */
+       input_unregister_handler(&cfb_input_handler);
+       /* cancel pending work requests */
+       cancel_work_sync(&boost);
+       cancel_delayed_work_sync(&unboost);
+       /* clean up */
+       destroy_workqueue(cfb_wq);
+       pm_qos_remove_request(&qos_req);
+}
+
+module_init(cfboost_init);
+module_exit(cfboost_exit);