-----Original Message-----
From: Eduardo Valentin [mailto:eduardo.valentin@ti.com]
Sent: Wednesday, November 13, 2013 3:46 AM
To: swarren@wwwdotorg.org; pawel.moll@arm.com; mark.rutland@arm.com;
ian.campbell@citrix.com; rob.herring@calxeda.com; linux@roeck-us.net;
Zhang, Rui
Cc: wni@nvidia.com; grant.likely@linaro.org; R, Durgadoss; linux-
pm@vger.kernel.org; devicetree@vger.kernel.org; lm-sensors@lm-
sensors.org; linux-kernel@vger.kernel.org; Eduardo Valentin; Rafael J.
Wysocki; Viresh Kumar; cpufreq@vger.kernel.org; devicetree-
discuss@lists.ozlabs.org
Subject: [PATCHv5 05/20] cpufreq: cpufreq-cpu0: add dt node parsing for
cooling device properties
Importance: High

This patch changes the cpufreq-cpu0 driver to consider if a cpu needs
cooling (with cpufreq). In case the cooling is needed, the cpu0 device
tree node needs to be properly configured with cooling device
properties.

In case these properties are present,, the driver will load a cpufreq
cooling device in the system. The cpufreq-cpu0 driver is not interested
in determining how the system should be using the cooling device. The
driver is responsible only of loading the cooling device.

Describing how the cooling device will be used can be accomplished by
setting up a thermal zone that references and is composed by the
cpufreq cooling device.

Cc: "Rafael J. Wysocki" <redacted>
Cc: Viresh Kumar <viresh.kumar@linaro.org>
Cc: Grant Likely <redacted>
Cc: Rob Herring <redacted>
Cc: cpufreq@vger.kernel.org
Cc: linux-pm@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: devicetree-discuss@lists.ozlabs.org
Signed-off-by: Eduardo Valentin <redacted>
---
 .../devicetree/bindings/cpufreq/cpufreq-cpu0.txt         |  7 +++++++
 drivers/cpufreq/Kconfig                                  |  2 +-
 drivers/cpufreq/cpufreq-cpu0.c                           | 16
++++++++++++++++
 3 files changed, 24 insertions(+), 1 deletion(-)

diff --git a/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt

b/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt
index 051f764..f055515 100644

--- a/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt
+++ b/Documentation/devicetree/bindings/cpufreq/cpufreq-cpu0.txt

@@ -15,6 +15,10 @@ Optional properties:
 - clock-latency: Specify the possible maximum transition latency for

clock,
   in unit of nanoseconds.
 - voltage-tolerance: Specify the CPU voltage tolerance in percentage.
+- #cooling-cells:
+- cooling-min-level:
+- cooling-max-level:
+     Please refer to
Documentation/devicetree/bindings/thermal/thermal.txt.

 Examples:

@@ -33,6 +37,9 @@ cpus {
 			198000  850000
 		>;
 		clock-latency = <61036>; /* two CLK32 periods */
+		#cooling-cells = <2>;
+		cooling-min-level = <0>;
+		cooling-max-level = <2>;
 	};

 	cpu@1 {

diff --git a/drivers/cpufreq/Kconfig b/drivers/cpufreq/Kconfig index

534fcb8..fc1e9a5 100644

--- a/drivers/cpufreq/Kconfig
+++ b/drivers/cpufreq/Kconfig

@@ -186,7 +186,7 @@ config CPU_FREQ_GOV_CONSERVATIVE

 config GENERIC_CPUFREQ_CPU0
 	tristate "Generic CPU0 cpufreq driver"
-	depends on HAVE_CLK && REGULATOR && PM_OPP && OF
+	depends on HAVE_CLK && REGULATOR && PM_OPP && OF && THERMAL &&
+CPU_THERMAL

 	select CPU_FREQ_TABLE
 	help
 	  This adds a generic cpufreq driver for CPU0 frequency
management.

diff --git a/drivers/cpufreq/cpufreq-cpu0.c b/drivers/cpufreq/cpufreq-

cpu0.c index c522a95..568aaf3 100644

--- a/drivers/cpufreq/cpufreq-cpu0.c
+++ b/drivers/cpufreq/cpufreq-cpu0.c

@@ -13,7 +13,9 @@

 #include <linux/clk.h>
 #include <linux/cpu.h>
+#include <linux/cpu_cooling.h>
 #include <linux/cpufreq.h>
+#include <linux/cpumask.h>
 #include <linux/err.h>
 #include <linux/module.h>
 #include <linux/of.h>

@@ -21,6 +23,7 @@
 #include <linux/platform_device.h>
 #include <linux/regulator/consumer.h>
 #include <linux/slab.h>
+#include <linux/thermal.h>

 static unsigned int transition_latency;  static unsigned int

voltage_tolerance; /* in percentage */ @@ -29,6 +32,7 @@ static struct
device *cpu_dev;  static struct clk *cpu_clk;  static struct regulator
*cpu_reg;  static struct cpufreq_frequency_table *freq_table;
+static struct thermal_cooling_device *cdev;

 static int cpu0_verify_speed(struct cpufreq_policy *policy)  { @@ -
260,6 +264,17 @@ static int cpu0_cpufreq_probe(struct platform_device
*pdev)
 		goto out_free_table;
 	}

+	/*
+	 * For now, just loading the cooling device;
+	 * thermal DT code takes care of matching them.
+	 */
+	if (of_find_property(np, "#cooling-cells", NULL)) {
+		cdev = of_cpufreq_cooling_register(np, cpu_present_mask);
+		if (IS_ERR(cdev))
+			pr_err("running cpufreq without cooling
device: %ld\n",
+			       PTR_ERR(cdev));
+	}
+
 	of_node_put(np);
 	return 0;

@@ -272,6 +287,7 @@ out_put_node:

 static int cpu0_cpufreq_remove(struct platform_device *pdev)  {
+	cpufreq_cooling_unregister(cdev);
 	cpufreq_unregister_driver(&cpu0_cpufreq_driver);
 	opp_free_cpufreq_table(cpu_dev, &freq_table);

--

1.8.2.1.342.gfa7285d