cpufreq: omap: remove driver

The omap-cpufreq driver is not used in the corresponding defconfigs.
The pseudo platform device to use it was removed by
commit cb6675d6a868 ("ARM: OMAP2+: Remove legacy PM init")
10 years ago.

Checking if there is any need to reactivate it:
For omap3, dra7 there is ti-cpufreq to create cpufreq-dt device
For omap2/4/5 there is cpufreq-dt-plat to create cpufreq-dt device.
For omap1 this driver cannot be selected at all.

So no users, no need to reactivate the driver somehow. So remove it.

Signed-off-by: Andreas Kemnade <[e-mail]>
Acked-by: Kevin Hilman <[e-mail]>
Link: https://patch.msgid.link/[e-mail]
Signed-off-by: Rafael J. Wysocki <[e-mail]>

drivers/cpufreq/Kconfig.arm

···
 	  The driver implements the cpufreq interface for this HW engine.
 	  Say Y if you want to support CPUFreq HW.
 
-config ARM_OMAP2PLUS_CPUFREQ
-	bool "TI OMAP2+"
-	depends on ARCH_OMAP2PLUS || COMPILE_TEST
-	default ARCH_OMAP2PLUS
-
 config ARM_QCOM_CPUFREQ_NVMEM
 	tristate "Qualcomm nvmem based CPUFreq"
 	depends on ARCH_QCOM || COMPILE_TEST

drivers/cpufreq/Makefile

···
 obj-$(CONFIG_ARM_MEDIATEK_CPUFREQ)	+= mediatek-cpufreq.o
 obj-$(CONFIG_ARM_MEDIATEK_CPUFREQ_HW)	+= mediatek-cpufreq-hw.o
 obj-$(CONFIG_MACH_MVEBU_V7)		+= mvebu-cpufreq.o
-obj-$(CONFIG_ARM_OMAP2PLUS_CPUFREQ)	+= omap-cpufreq.o
 obj-$(CONFIG_ARM_PXA2xx_CPUFREQ)	+= pxa2xx-cpufreq.o
 obj-$(CONFIG_PXA3xx)			+= pxa3xx-cpufreq.o
 obj-$(CONFIG_ARM_QCOM_CPUFREQ_HW)	+= qcom-cpufreq-hw.o

drivers/cpufreq/omap-cpufreq.c

···
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- *  CPU frequency scaling for OMAP using OPP information
- *
- *  Copyright (C) 2005 Nokia Corporation
- *  Written by Tony Lindgren <[e-mail]>
- *
- *  Based on cpu-sa1110.c, Copyright (C) 2001 Russell King
- *
- * Copyright (C) 2007-2011 Texas Instruments, Inc.
- * - OMAP3/4 support by Rajendra Nayak, Santosh Shilimkar
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/types.h>
-#include <linux/kernel.h>
-#include <linux/sched.h>
-#include <linux/cpufreq.h>
-#include <linux/delay.h>
-#include <linux/init.h>
-#include <linux/err.h>
-#include <linux/clk.h>
-#include <linux/io.h>
-#include <linux/pm_opp.h>
-#include <linux/cpu.h>
-#include <linux/module.h>
-#include <linux/platform_device.h>
-#include <linux/regulator/consumer.h>
-
-/* OPP tolerance in percentage */
-#define	OPP_TOLERANCE	4
-
-static struct cpufreq_frequency_table *freq_table;
-static atomic_t freq_table_users = ATOMIC_INIT(0);
-static struct device *mpu_dev;
-static struct regulator *mpu_reg;
-
-static int omap_target(struct cpufreq_policy *policy, unsigned int index)
-{
-	int r, ret;
-	struct dev_pm_opp *opp;
-	unsigned long freq, volt = 0, volt_old = 0, tol = 0;
-	unsigned int old_freq, new_freq;
-
-	old_freq = policy->cur;
-	new_freq = freq_table[index].frequency;
-
-	freq = new_freq * 1000;
-	ret = clk_round_rate(policy->clk, freq);
-	if (ret < 0) {
-		dev_warn(mpu_dev,
-			 "CPUfreq: Cannot find matching frequency for %lu\n",
-			 freq);
-		return ret;
-	}
-	freq = ret;
-
-	if (mpu_reg) {
-		opp = dev_pm_opp_find_freq_ceil(mpu_dev, &freq);
-		if (IS_ERR(opp)) {
-			dev_err(mpu_dev, "%s: unable to find MPU OPP for %d\n",
-				__func__, new_freq);
-			return -EINVAL;
-		}
-		volt = dev_pm_opp_get_voltage(opp);
-		dev_pm_opp_put(opp);
-		tol = volt * OPP_TOLERANCE / 100;
-		volt_old = regulator_get_voltage(mpu_reg);
-	}
-
-	dev_dbg(mpu_dev, "cpufreq-omap: %u MHz, %ld mV --> %u MHz, %ld mV\n", 
-		old_freq / 1000, volt_old ? volt_old / 1000 : -1,
-		new_freq / 1000, volt ? volt / 1000 : -1);
-
-	/* scaling up?  scale voltage before frequency */
-	if (mpu_reg && (new_freq > old_freq)) {
-		r = regulator_set_voltage(mpu_reg, volt - tol, volt + tol);
-		if (r < 0) {
-			dev_warn(mpu_dev, "%s: unable to scale voltage up.\n",
-				 __func__);
-			return r;
-		}
-	}
-
-	ret = clk_set_rate(policy->clk, new_freq * 1000);
-
-	/* scaling down?  scale voltage after frequency */
-	if (mpu_reg && (new_freq < old_freq)) {
-		r = regulator_set_voltage(mpu_reg, volt - tol, volt + tol);
-		if (r < 0) {
-			dev_warn(mpu_dev, "%s: unable to scale voltage down.\n",
-				 __func__);
-			clk_set_rate(policy->clk, old_freq * 1000);
-			return r;
-		}
-	}
-
-	return ret;
-}
-
-static inline void freq_table_free(void)
-{
-	if (atomic_dec_and_test(&freq_table_users))
-		dev_pm_opp_free_cpufreq_table(mpu_dev, &freq_table);
-}
-
-static int omap_cpu_init(struct cpufreq_policy *policy)
-{
-	int result;
-
-	policy->clk = clk_get(NULL, "cpufreq_ck");
-	if (IS_ERR(policy->clk))
-		return PTR_ERR(policy->clk);
-
-	if (!freq_table) {
-		result = dev_pm_opp_init_cpufreq_table(mpu_dev, &freq_table);
-		if (result) {
-			dev_err(mpu_dev,
-				"%s: cpu%d: failed creating freq table[%d]\n",
-				__func__, policy->cpu, result);
-			clk_put(policy->clk);
-			return result;
-		}
-	}
-
-	atomic_inc_return(&freq_table_users);
-
-	/* FIXME: what's the actual transition time? */
-	cpufreq_generic_init(policy, freq_table, 300 * 1000);
-
-	return 0;
-}
-
-static void omap_cpu_exit(struct cpufreq_policy *policy)
-{
-	freq_table_free();
-	clk_put(policy->clk);
-}
-
-static struct cpufreq_driver omap_driver = {
-	.flags		= CPUFREQ_NEED_INITIAL_FREQ_CHECK,
-	.verify		= cpufreq_generic_frequency_table_verify,
-	.target_index	= omap_target,
-	.get		= cpufreq_generic_get,
-	.init		= omap_cpu_init,
-	.exit		= omap_cpu_exit,
-	.register_em	= cpufreq_register_em_with_opp,
-	.name		= "omap",
-};
-
-static int omap_cpufreq_probe(struct platform_device *pdev)
-{
-	mpu_dev = get_cpu_device(0);
-	if (!mpu_dev) {
-		pr_warn("%s: unable to get the MPU device\n", __func__);
-		return -EINVAL;
-	}
-
-	mpu_reg = regulator_get(mpu_dev, "vcc");
-	if (IS_ERR(mpu_reg)) {
-		pr_warn("%s: unable to get MPU regulator\n", __func__);
-		mpu_reg = NULL;
-	} else {
-		/* 
-		 * Ensure physical regulator is present.
-		 * (e.g. could be dummy regulator.)
-		 */
-		if (regulator_get_voltage(mpu_reg) < 0) {
-			pr_warn("%s: physical regulator not present for MPU\n",
-				__func__);
-			regulator_put(mpu_reg);
-			mpu_reg = NULL;
-		}
-	}
-
-	return cpufreq_register_driver(&omap_driver);
-}
-
-static void omap_cpufreq_remove(struct platform_device *pdev)
-{
-	cpufreq_unregister_driver(&omap_driver);
-}
-
-static struct platform_driver omap_cpufreq_platdrv = {
-	.driver = {
-		.name	= "omap-cpufreq",
-	},
-	.probe		= omap_cpufreq_probe,
-	.remove		= omap_cpufreq_remove,
-};
-module_platform_driver(omap_cpufreq_platdrv);
-
-MODULE_DESCRIPTION("cpufreq driver for OMAP SoCs");
-MODULE_LICENSE("GPL");