[Unstable][PATCH] UBUNTU: SAUCE: Revert "UBUNTU: SAUCE: (no-up) Allow filtering of cpufreq drivers"

[Juerg Haefliger]

BugLink: https://bugs.launchpad.net/bugs/2089676

This is ancient and likely no longer needed. And it introduced a compile
warning.

drivers/cpufreq/cpufreq.c: In function ‘cpufreq_register_driver’:
drivers/cpufreq/cpufreq.c:2912:21: warning: the comparison will always evaluate as ‘true’ for the address of ‘name’ will never be NULL [-Waddress]
 2912 |                 if (!driver_data->name ||
      |                     ^
In file included from /<<PKGBUILDDIR>>/drivers/cpufreq/cpufreq.c:18:
include/linux/cpufreq.h:326:25: note: ‘name’ declared here
  326 |         char            name[CPUFREQ_NAME_LEN];
      |                         ^~~~

Signed-off-by: Juerg Haefliger <juerg.haefliger at canonical.com>
---
 .../admin-guide/kernel-parameters.txt         |  4 ----
 drivers/cpufreq/cpufreq.c                     | 22 +------------------
 2 files changed, 1 insertion(+), 25 deletions(-)

diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt
index 9d205cd0d0f1..3246cfff44fe 100644
--- a/Documentation/admin-guide/kernel-parameters.txt
+++ b/Documentation/admin-guide/kernel-parameters.txt
@@ -891,10 +891,6 @@
 			Format:
 			<first_slot>,<last_slot>,<port>,<enum_bit>[,<debug>]
 
-	cpufreq_driver= [X86] Allow only the named cpu frequency scaling driver
-			to register. Example: cpufreq_driver=powernow-k8
-			Format: { none | STRING }
-
 	cpuidle.off=1	[CPU_IDLE]
 			disable the cpuidle sub-system
 
diff --git a/drivers/cpufreq/cpufreq.c b/drivers/cpufreq/cpufreq.c
index 4e9eb07704e5..f98c9438760c 100644
--- a/drivers/cpufreq/cpufreq.c
+++ b/drivers/cpufreq/cpufreq.c
@@ -2880,20 +2880,6 @@ static int cpuhp_cpufreq_offline(unsigned int cpu)
 	return 0;
 }
 
-static char cpufreq_driver_name[CPUFREQ_NAME_LEN];
-
-static int __init cpufreq_driver_setup(char *str)
-{
-	strscpy(cpufreq_driver_name, str, CPUFREQ_NAME_LEN);
-	return 1;
-}
-
-/*
- * Set this name to only allow one specific cpu freq driver, e.g.,
- * cpufreq_driver=powernow-k8
- */
-__setup("cpufreq_driver=", cpufreq_driver_setup);
-
 /**
  * cpufreq_register_driver - register a CPU Frequency driver
  * @driver_data: A struct cpufreq_driver containing the values#
@@ -2929,13 +2915,7 @@ int cpufreq_register_driver(struct cpufreq_driver *driver_data)
 		 (driver_data->adjust_perf && !driver_data->fast_switch))
 		return -EINVAL;
 
-	pr_debug("trying to register driver %s, cpufreq_driver=%s\n",
-		driver_data->name, cpufreq_driver_name);
-
-	if (cpufreq_driver_name[0])
-		if (!driver_data->name ||
-			strcmp(cpufreq_driver_name, driver_data->name))
-				return -EINVAL;
+	pr_debug("trying to register driver %s\n", driver_data->name);
 
 	/* Protect against concurrent CPU online/offline. */
 	cpus_read_lock();
-- 
2.43.0