[PATCH 1/2] cpufreq: qoriq: convert to a platform driver

From: Mian Yousaf Kaukab
Date: Fri Apr 03 2020 - 17:21:53 EST


The driver has to be manually loaded if it is built as a module. It
is neither exporting MODULE_DEVICE_TABLE nor MODULE_ALIAS. Moreover,
no platform-device is created (and thus no uevent is sent) for the
clockgen nodes it depends on.

Convert the module to a platform driver with its own alias. Moreover,
drop whitelisted SOCs. Platform device will be created only for the
compatible platforms.

Signed-off-by: Mian Yousaf Kaukab <ykaukab@xxxxxxx>
---
drivers/cpufreq/qoriq-cpufreq.c | 76 ++++++++++++++++-------------------------
1 file changed, 29 insertions(+), 47 deletions(-)

diff --git a/drivers/cpufreq/qoriq-cpufreq.c b/drivers/cpufreq/qoriq-cpufreq.c
index 8e436dc75c8b..6b6b20da2bcf 100644
--- a/drivers/cpufreq/qoriq-cpufreq.c
+++ b/drivers/cpufreq/qoriq-cpufreq.c
@@ -18,6 +18,7 @@
#include <linux/of.h>
#include <linux/slab.h>
#include <linux/smp.h>
+#include <linux/platform_device.h>

/**
* struct cpu_data
@@ -29,12 +30,6 @@ struct cpu_data {
struct cpufreq_frequency_table *table;
};

-/*
- * Don't use cpufreq on this SoC -- used when the SoC would have otherwise
- * matched a more generic compatible.
- */
-#define SOC_BLACKLIST 1
-
/**
* struct soc_data - SoC specific data
* @flags: SOC_xxx
@@ -264,64 +259,51 @@ static struct cpufreq_driver qoriq_cpufreq_driver = {
.attr = cpufreq_generic_attr,
};

-static const struct soc_data blacklist = {
- .flags = SOC_BLACKLIST,
-};
-
-static const struct of_device_id node_matches[] __initconst = {
+static const struct of_device_id qoriq_cpufreq_blacklist[] = {
/* e6500 cannot use cpufreq due to erratum A-008083 */
- { .compatible = "fsl,b4420-clockgen", &blacklist },
- { .compatible = "fsl,b4860-clockgen", &blacklist },
- { .compatible = "fsl,t2080-clockgen", &blacklist },
- { .compatible = "fsl,t4240-clockgen", &blacklist },
-
- { .compatible = "fsl,ls1012a-clockgen", },
- { .compatible = "fsl,ls1021a-clockgen", },
- { .compatible = "fsl,ls1028a-clockgen", },
- { .compatible = "fsl,ls1043a-clockgen", },
- { .compatible = "fsl,ls1046a-clockgen", },
- { .compatible = "fsl,ls1088a-clockgen", },
- { .compatible = "fsl,ls2080a-clockgen", },
- { .compatible = "fsl,lx2160a-clockgen", },
- { .compatible = "fsl,p4080-clockgen", },
- { .compatible = "fsl,qoriq-clockgen-1.0", },
- { .compatible = "fsl,qoriq-clockgen-2.0", },
+ { .compatible = "fsl,b4420-clockgen", },
+ { .compatible = "fsl,b4860-clockgen", },
+ { .compatible = "fsl,t2080-clockgen", },
+ { .compatible = "fsl,t4240-clockgen", },
{}
};

-static int __init qoriq_cpufreq_init(void)
+static int qoriq_cpufreq_probe(struct platform_device *pdev)
{
int ret;
- struct device_node *np;
- const struct of_device_id *match;
- const struct soc_data *data;
-
- np = of_find_matching_node(NULL, node_matches);
- if (!np)
- return -ENODEV;
-
- match = of_match_node(node_matches, np);
- data = match->data;
-
- of_node_put(np);
+ struct device_node *np;

- if (data && data->flags & SOC_BLACKLIST)
+ np = of_find_matching_node(NULL, qoriq_cpufreq_blacklist);
+ if (np) {
+ dev_info(&pdev->dev, "Disabling due to erratum A-008083");
return -ENODEV;
+ }

ret = cpufreq_register_driver(&qoriq_cpufreq_driver);
- if (!ret)
- pr_info("Freescale QorIQ CPU frequency scaling driver\n");
+ if (ret)
+ return ret;

- return ret;
+ dev_info(&pdev->dev, "Freescale QorIQ CPU frequency scaling driver\n");
+ return 0;
}
-module_init(qoriq_cpufreq_init);

-static void __exit qoriq_cpufreq_exit(void)
+static int qoriq_cpufreq_remove(struct platform_device *pdev)
{
cpufreq_unregister_driver(&qoriq_cpufreq_driver);
+
+ return 0;
}
-module_exit(qoriq_cpufreq_exit);

+static struct platform_driver qoriq_cpufreq_platform_driver = {
+ .driver = {
+ .name = "qoriq-cpufreq",
+ },
+ .probe = qoriq_cpufreq_probe,
+ .remove = qoriq_cpufreq_remove,
+};
+module_platform_driver(qoriq_cpufreq_platform_driver);
+
+MODULE_ALIAS("platform:qoriq-cpufreq");
MODULE_LICENSE("GPL");
MODULE_AUTHOR("Tang Yuantian <Yuantian.Tang@xxxxxxxxxxxxx>");
MODULE_DESCRIPTION("cpufreq driver for Freescale QorIQ series SoCs");
--
2.16.4