[PATCH] cpufreq: qcom-hw: add missing devm_release_mem_region() call

[Shawn Guo <shawn.guo@linaro.org>]

On SDM845/850, running the following commands to put all cores in
freq-domain1 offline and then get one core back online, there will be
a request region error seen from qcom-hw driver.

$ echo 0 > /sys/devices/system/cpu/cpu4/online
$ echo 0 > /sys/devices/system/cpu/cpu5/online
$ echo 0 > /sys/devices/system/cpu/cpu6/online
$ echo 0 > /sys/devices/system/cpu/cpu7/online
$ echo 1 > /sys/devices/system/cpu/cpu4/online

[ 3395.915416] CPU4: shutdown
[ 3395.938185] psci: CPU4 killed (polled 0 ms)
[ 3399.071424] CPU5: shutdown
[ 3399.094316] psci: CPU5 killed (polled 0 ms)
[ 3402.139358] CPU6: shutdown
[ 3402.161705] psci: CPU6 killed (polled 0 ms)
[ 3404.742939] CPU7: shutdown
[ 3404.765592] psci: CPU7 killed (polled 0 ms)
[ 3411.492274] Detected VIPT I-cache on CPU4
[ 3411.492337] GICv3: CPU4: found redistributor 400 region 0:0x0000000017ae0000
[ 3411.492448] CPU4: Booted secondary processor 0x0000000400 [0x516f802d]
[ 3411.503654] qcom-cpufreq-hw 17d43000.cpufreq: can't request region for resource [mem 0x17d45800-0x17d46bff]

The cause is that the memory region requested in .init hook doesn't get
released in .exit hook, and the subsequent call to .init will always fail
on this error.  Let's break down the devm_platform_ioremap_resource()
call a bit, so that we can have the resource pointer to release memory
region from .exit hook.

Signed-off-by: Shawn Guo <shawn.guo@linaro.org>
---
 drivers/cpufreq/qcom-cpufreq-hw.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/drivers/cpufreq/qcom-cpufreq-hw.c b/drivers/cpufreq/qcom-cpufreq-hw.c
index 9ed5341dc515..315ee987d2d3 100644
--- a/drivers/cpufreq/qcom-cpufreq-hw.c
+++ b/drivers/cpufreq/qcom-cpufreq-hw.c
@@ -32,6 +32,7 @@ struct qcom_cpufreq_soc_data {
 
 struct qcom_cpufreq_data {
 	void __iomem *base;
+	struct resource *res;
 	const struct qcom_cpufreq_soc_data *soc_data;
 };
 
@@ -280,6 +281,7 @@ static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
 	struct of_phandle_args args;
 	struct device_node *cpu_np;
 	struct device *cpu_dev;
+	struct resource *res;
 	void __iomem *base;
 	struct qcom_cpufreq_data *data;
 	int ret, index;
@@ -303,7 +305,8 @@ static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
 
 	index = args.args[0];
 
-	base = devm_platform_ioremap_resource(pdev, index);
+	res = platform_get_resource(pdev, IORESOURCE_MEM, index);
+	base = devm_ioremap_resource(dev, res);
 	if (IS_ERR(base))
 		return PTR_ERR(base);
 
@@ -315,6 +318,7 @@ static int qcom_cpufreq_hw_cpu_init(struct cpufreq_policy *policy)
 
 	data->soc_data = of_device_get_match_data(&pdev->dev);
 	data->base = base;
+	data->res = res;
 
 	/* HW should be in enabled state to proceed */
 	if (!(readl_relaxed(base + data->soc_data->reg_enable) & 0x1)) {
@@ -358,11 +362,13 @@ static int qcom_cpufreq_hw_cpu_exit(struct cpufreq_policy *policy)
 	struct device *cpu_dev = get_cpu_device(policy->cpu);
 	struct qcom_cpufreq_data *data = policy->driver_data;
 	struct platform_device *pdev = cpufreq_get_driver_data();
+	struct resource *res = data->res;
 
 	dev_pm_opp_remove_all_dynamic(cpu_dev);
 	dev_pm_opp_of_cpumask_remove_table(policy->related_cpus);
 	kfree(policy->freq_table);
 	devm_iounmap(&pdev->dev, data->base);
+	devm_release_mem_region(&pdev->dev, res->start, resource_size(res));
 
 	return 0;
 }
-- 
2.17.1