arm: tegra: xmm: pm qos for modem enumeration

XMM modem first enumeration has timing requirement, so khubd
should perform enum within 1 second. An issue is seen sometimes
when the hub events are not sent on time (on fully loaded system)
and then khubd timesout. This patch adds PM QOS request to bump up
the cpu frequency for 2 seconds.

Bug 946027

Change-Id: I1a43c043d42cfa442517a2a7ad8d69a934d4ab47
Signed-off-by: Vinayak Pane <vpane@nvidia.com>
Reviewed-on: http://git-master/r/102697
Reviewed-by: Simone Willett <swillett@nvidia.com>
Tested-by: Simone Willett <swillett@nvidia.com>

1 files changed, 25 insertions, 0 deletions

diff --git a/arch/arm/mach-tegra/baseband-xmm-power.c b/arch/arm/mach-tegra/baseband-xmm-power.c
index 75ad8d28d475..20f8d306f901 100644
--- a/arch/arm/mach-tegra/baseband-xmm-power.c
+++ b/arch/arm/mach-tegra/baseband-xmm-power.c
@@ -31,6 +31,7 @@
 #include <linux/usb.h>
 #include <linux/pm_runtime.h>
 #include <linux/suspend.h>
+#include <linux/pm_qos_params.h>
 #include <mach/usb_phy.h>
 #include "board.h"
 #include "board-enterprise.h"
@@ -109,6 +110,9 @@ static DEFINE_MUTEX(xmm_onoff_mutex);
 static bool system_suspending;
 static struct regulator *enterprise_hsic_reg;
 static bool _hsic_reg_status;
+static struct pm_qos_request_list boost_cpu_freq_req;
+static struct delayed_work pm_qos_work;
+#define BOOST_CPU_FREQ_MIN	1500000
 
 /* driver specific data - same structure is used for flashless
  * & flashed modem drivers i.e. baseband-xmm-power2.c
@@ -190,6 +194,13 @@ static int baseband_modem_power_on(struct baseband_power_platform_data *data)
 	udelay(70);
 	gpio_set_value(data->modem.xmm.bb_on, 0);
 
+	pr_debug("%s: pm qos request CPU 1.5GHz\n", __func__);
+	pm_qos_update_request(&boost_cpu_freq_req, (s32)BOOST_CPU_FREQ_MIN);
+	/* Device enumeration should happen in 1 sec however in any case
+	 * we want to request it back to normal so schedule work to restore
+	 * CPU freq after 2 seconds */
+	schedule_delayed_work(&pm_qos_work, msecs_to_jiffies(2000));
+
 	return 0;
 }
 
@@ -358,6 +369,13 @@ static ssize_t xmm_onoff(struct device *dev, struct device_attribute *attr,
 	return count;
 }
 
+static void pm_qos_worker(struct work_struct *work)
+{
+	pr_debug("%s - pm qos CPU back to normal\n", __func__);
+	pm_qos_update_request(&boost_cpu_freq_req,
+			(s32)PM_QOS_CPU_FREQ_MIN_DEFAULT_VALUE);
+}
+
 static DEVICE_ATTR(xmm_onoff, S_IRUSR | S_IWUSR | S_IRGRP,
 		NULL, xmm_onoff);
 
@@ -1144,6 +1162,11 @@ static struct platform_driver baseband_power_driver = {
 static int __init xmm_power_init(void)
 {
 	pr_debug("%s\n", __func__);
+
+	INIT_DELAYED_WORK(&pm_qos_work, pm_qos_worker);
+	pm_qos_add_request(&boost_cpu_freq_req, PM_QOS_CPU_FREQ_MIN,
+			(s32)PM_QOS_CPU_FREQ_MIN_DEFAULT_VALUE);
+
 	return platform_driver_register(&baseband_power_driver);
 }
 
@@ -1151,6 +1174,8 @@ static void __exit xmm_power_exit(void)
 {
 	pr_debug("%s\n", __func__);
 	platform_driver_unregister(&baseband_power_driver);
+
+	pm_qos_remove_request(&boost_cpu_freq_req);
 }
 
 module_init(xmm_power_init)