Commit 5553f9e2 authored by Shawn Guo's avatar Shawn Guo Committed by Rafael J. Wysocki
Browse files

cpufreq: instantiate cpufreq-cpu0 as a platform_driver

As multiplatform build is being adopted by more and more ARM platforms,
initcall function should be used very carefully.  For example, when
GENERIC_CPUFREQ_CPU0 is built in the kernel, cpu0_cpufreq_driver_init()
will be called on all the platforms to initialize cpufreq-cpu0 driver.

To eliminate this undesired the effect, the patch changes cpufreq-cpu0
driver to have it instantiated as a platform_driver.  Then it will only
run on platforms that create the platform_device "cpufreq-cpu0".

Along with the change, it also changes cpu_dev to be &pdev->dev,
so that managed functions can start working, and module build gets
supported too.

The highbank-cpufreq driver is also updated accordingly to adapt the
changes on cpufreq-cpu0.
Signed-off-by: default avatarShawn Guo <>
Reviewed-by: default avatarViresh Kumar <>
Acked-by: default avatarMark Langsdorf <>
Signed-off-by: default avatarRafael J. Wysocki <>
parent 58ddcead
......@@ -185,7 +185,7 @@ config CPU_FREQ_GOV_CONSERVATIVE
If in doubt, say N.
bool "Generic CPU0 cpufreq driver"
tristate "Generic CPU0 cpufreq driver"
depends on HAVE_CLK && REGULATOR && PM_OPP && OF
......@@ -12,12 +12,12 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/clk.h>
#include <linux/cpu.h>
#include <linux/cpufreq.h>
#include <linux/err.h>
#include <linux/module.h>
#include <linux/of.h>
#include <linux/opp.h>
#include <linux/platform_device.h>
#include <linux/regulator/consumer.h>
#include <linux/slab.h>
......@@ -177,7 +177,7 @@ static struct cpufreq_driver cpu0_cpufreq_driver = {
.attr = cpu0_cpufreq_attr,
static int cpu0_cpufreq_driver_init(void)
static int cpu0_cpufreq_probe(struct platform_device *pdev)
struct device_node *np;
int ret;
......@@ -192,23 +192,17 @@ static int cpu0_cpufreq_driver_init(void)
return -ENOENT;
cpu_dev = get_cpu_device(0);
if (!cpu_dev) {
pr_err("failed to get cpu0 device\n");
ret = -ENODEV;
goto out_put_node;
cpu_dev = &pdev->dev;
cpu_dev->of_node = np;
cpu_clk = clk_get(cpu_dev, NULL);
cpu_clk = devm_clk_get(cpu_dev, NULL);
if (IS_ERR(cpu_clk)) {
ret = PTR_ERR(cpu_clk);
pr_err("failed to get cpu0 clock: %d\n", ret);
goto out_put_node;
cpu_reg = regulator_get(cpu_dev, "cpu0");
cpu_reg = devm_regulator_get(cpu_dev, "cpu0");
if (IS_ERR(cpu_reg)) {
pr_warn("failed to get cpu0 regulator\n");
cpu_reg = NULL;
......@@ -271,7 +265,24 @@ out_put_node:
return ret;
static int cpu0_cpufreq_remove(struct platform_device *pdev)
opp_free_cpufreq_table(cpu_dev, &freq_table);
return 0;
static struct platform_driver cpu0_cpufreq_platdrv = {
.driver = {
.name = "cpufreq-cpu0",
.owner = THIS_MODULE,
.probe = cpu0_cpufreq_probe,
.remove = cpu0_cpufreq_remove,
MODULE_AUTHOR("Shawn Guo <>");
MODULE_DESCRIPTION("Generic CPU0 cpufreq driver");
......@@ -20,6 +20,7 @@
#include <linux/err.h>
#include <linux/of.h>
#include <linux/mailbox.h>
#include <linux/platform_device.h>
#define HB_CPUFREQ_CHANGE_NOTE 0x80000001
......@@ -65,6 +66,7 @@ static struct notifier_block hb_cpufreq_clk_nb = {
static int hb_cpufreq_driver_init(void)
struct platform_device_info devinfo = { .name = "cpufreq-cpu0", };
struct device *cpu_dev;
struct clk *cpu_clk;
struct device_node *np;
......@@ -104,6 +106,9 @@ static int hb_cpufreq_driver_init(void)
goto out_put_node;
/* Instantiate cpufreq-cpu0 */
return ret;
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