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path: root/demos/AVR-ATmega128-GCC/main.c
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/*
    ChibiOS/RT - Copyright (C) 2006,2007,2008,2009,2010,
                 2011 Giovanni Di Sirio.

    This file is part of ChibiOS/RT.

    ChibiOS/RT is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    ChibiOS/RT is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "ch.h"
#include "hal.h"
#include "evtimer.h"

#include "lcd.h"

static WORKING_AREA(waThread1, 32);
static msg_t Thread1(void *arg) {

  while (TRUE) {
    if (!(PINA & PORTA_BUTTON2))
      PORTA ^= PORTA_RELAY;
    chThdSleepMilliseconds(1000);
  }
  return 0;
}

static void TimerHandler(eventid_t id) {
  msg_t TestThread(void *p);

  if (!(PINA & PORTA_BUTTON1))
    TestThread(&SD2);
}

/*
 * Application entry point.
 */
int main(void) {
  static EvTimer evt;
  static evhandler_t handlers[1] = {
    TimerHandler
  };
  static EventListener el0;

  /*
   * System initializations.
   * - HAL initialization, this also initializes the configured device drivers
   *   and performs the board-specific initializations.
   * - Kernel initialization, the main() function becomes a thread and the
   *   RTOS is active.
   */
  halInit();
  chSysInit();

  /*
   * Activates the serial driver 2 using the driver default configuration.
   */
  sdStart(&SD2, NULL);

  /*
   * This initialization requires the OS already active because it uses delay
   * APIs inside.
   */
  lcdInit();
  lcdCmd(LCD_CLEAR);
  lcdPuts(LCD_LINE1, "   ChibiOS/RT   ");
  lcdPuts(LCD_LINE2, "  Hello World!  ");

  /*
   * Event Timer initialization.
   */
  evtInit(&evt, MS2ST(500));            /* Initializes an event timer object.   */
  evtStart(&evt);                       /* Starts the event timer.              */
  chEvtRegister(&evt.et_es, &el0, 0);   /* Registers on the timer event source. */

  /*
   * Starts the LED blinker thread.
   */
  chThdCreateStatic(waThread1, sizeof(waThread1), NORMALPRIO, Thread1, NULL);

  while(TRUE)
    chEvtDispatch(handlers, chEvtWaitOne(ALL_EVENTS));

  return 0;
}
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From 7d12709544b8b3fb9727a34a664b8380e1e3493a Mon Sep 17 00:00:00 2001
From: Sricharan R <sricharan@codeaurora.org>
Date: Thu, 25 Jul 2019 12:41:31 +0200
Subject: [PATCH] cpufreq: qcom: Re-organise kryo cpufreq to use it for other
 nvmem based qcom socs

The kryo cpufreq driver reads the nvmem cell and uses that data to
populate the opps. There are other qcom cpufreq socs like krait which
does similar thing. Except for the interpretation of the read data,
rest of the driver is same for both the cases. So pull the common things
out for reuse.

Signed-off-by: Sricharan R <sricharan@codeaurora.org>
[niklas.cassel@linaro.org: split dt-binding into a separate patch and
do not rename the compatible string. Update MAINTAINERS file.]
Signed-off-by: Niklas Cassel <niklas.cassel@linaro.org>
Reviewed-by: Ilia Lin <ilia.lin@kernel.org>
Reviewed-by: Stephen Boyd <sboyd@kernel.org>
Signed-off-by: Viresh Kumar <viresh.kumar@linaro.org>
---
 MAINTAINERS                                   |   4 +-
 drivers/cpufreq/Kconfig.arm                   |   4 +-
 drivers/cpufreq/Makefile                      |   2 +-
 ...om-cpufreq-kryo.c => qcom-cpufreq-nvmem.c} | 122 +++++++++++-------
 4 files changed, 78 insertions(+), 54 deletions(-)
 rename drivers/cpufreq/{qcom-cpufreq-kryo.c => qcom-cpufreq-nvmem.c} (69%)

--- a/drivers/cpufreq/Kconfig.arm
+++ b/drivers/cpufreq/Kconfig.arm
@@ -110,8 +110,8 @@ config ARM_OMAP2PLUS_CPUFREQ
 	depends on ARCH_OMAP2PLUS
 	default ARCH_OMAP2PLUS
 
-config ARM_QCOM_CPUFREQ_KRYO
-	tristate "Qualcomm Kryo based CPUFreq"
+config ARM_QCOM_CPUFREQ_NVMEM
+	tristate "Qualcomm nvmem based CPUFreq"
 	depends on ARM64
 	depends on QCOM_QFPROM
 	depends on QCOM_SMEM
--- a/drivers/cpufreq/Makefile
+++ b/drivers/cpufreq/Makefile
@@ -64,7 +64,7 @@ obj-$(CONFIG_MACH_MVEBU_V7)		+= mvebu-cp
 obj-$(CONFIG_ARM_OMAP2PLUS_CPUFREQ)	+= omap-cpufreq.o
 obj-$(CONFIG_ARM_PXA2xx_CPUFREQ)	+= pxa2xx-cpufreq.o
 obj-$(CONFIG_PXA3xx)			+= pxa3xx-cpufreq.o
-obj-$(CONFIG_ARM_QCOM_CPUFREQ_KRYO)	+= qcom-cpufreq-kryo.o
+obj-$(CONFIG_ARM_QCOM_CPUFREQ_NVMEM)	+= qcom-cpufreq-nvmem.o
 obj-$(CONFIG_ARM_S3C2410_CPUFREQ)	+= s3c2410-cpufreq.o
 obj-$(CONFIG_ARM_S3C2412_CPUFREQ)	+= s3c2412-cpufreq.o
 obj-$(CONFIG_ARM_S3C2416_CPUFREQ)	+= s3c2416-cpufreq.o
--- a/drivers/cpufreq/qcom-cpufreq-kryo.c
+++ /dev/null
@@ -1,249 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Copyright (c) 2018, The Linux Foundation. All rights reserved.
- */
-
-/*
- * In Certain QCOM SoCs like apq8096 and msm8996 that have KRYO processors,
- * the CPU frequency subset and voltage value of each OPP varies
- * based on the silicon variant in use. Qualcomm Process Voltage Scaling Tables
- * defines the voltage and frequency value based on the msm-id in SMEM
- * and speedbin blown in the efuse combination.
- * The qcom-cpufreq-kryo driver reads the msm-id and efuse value from the SoC
- * to provide the OPP framework with required information.
- * This is used to determine the voltage and frequency value for each OPP of
- * operating-points-v2 table when it is parsed by the OPP framework.
- */
-
-#include <linux/cpu.h>
-#include <linux/err.h>
-#include <linux/init.h>
-#include <linux/kernel.h>
-#include <linux/module.h>
-#include <linux/nvmem-consumer.h>
-#include <linux/of.h>
-#include <linux/platform_device.h>
-#include <linux/pm_opp.h>
-#include <linux/slab.h>
-#include <linux/soc/qcom/smem.h>
-
-#define MSM_ID_SMEM	137
-
-enum _msm_id {
-	MSM8996V3 = 0xF6ul,
-	APQ8096V3 = 0x123ul,
-	MSM8996SG = 0x131ul,
-	APQ8096SG = 0x138ul,
-};
-
-enum _msm8996_version {
-	MSM8996_V3,
-	MSM8996_SG,
-	NUM_OF_MSM8996_VERSIONS,
-};
-
-static struct platform_device *cpufreq_dt_pdev, *kryo_cpufreq_pdev;
-
-static enum _msm8996_version qcom_cpufreq_kryo_get_msm_id(void)
-{
-	size_t len;
-	u32 *msm_id;
-	enum _msm8996_version version;
-
-	msm_id = qcom_smem_get(QCOM_SMEM_HOST_ANY, MSM_ID_SMEM, &len);
-	if (IS_ERR(msm_id))
-		return NUM_OF_MSM8996_VERSIONS;
-
-	/* The first 4 bytes are format, next to them is the actual msm-id */
-	msm_id++;
-
-	switch ((enum _msm_id)*msm_id) {
-	case MSM8996V3:
-	case APQ8096V3:
-		version = MSM8996_V3;
-		break;
-	case MSM8996SG:
-	case APQ8096SG:
-		version = MSM8996_SG;
-		break;
-	default:
-		version = NUM_OF_MSM8996_VERSIONS;
-	}
-
-	return version;
-}
-
-static int qcom_cpufreq_kryo_probe(struct platform_device *pdev)
-{
-	struct opp_table **opp_tables;
-	enum _msm8996_version msm8996_version;
-	struct nvmem_cell *speedbin_nvmem;
-	struct device_node *np;
-	struct device *cpu_dev;
-	unsigned cpu;
-	u8 *speedbin;
-	u32 versions;
-	size_t len;
-	int ret;
-
-	cpu_dev = get_cpu_device(0);
-	if (!cpu_dev)
-		return -ENODEV;
-
-	msm8996_version = qcom_cpufreq_kryo_get_msm_id();
-	if (NUM_OF_MSM8996_VERSIONS == msm8996_version) {
-		dev_err(cpu_dev, "Not Snapdragon 820/821!");
-		return -ENODEV;
-	}
-
-	np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
-	if (!np)
-		return -ENOENT;
-
-	ret = of_device_is_compatible(np, "operating-points-v2-kryo-cpu");
-	if (!ret) {
-		of_node_put(np);
-		return -ENOENT;
-	}
-
-	speedbin_nvmem = of_nvmem_cell_get(np, NULL);
-	of_node_put(np);
-	if (IS_ERR(speedbin_nvmem)) {
-		if (PTR_ERR(speedbin_nvmem) != -EPROBE_DEFER)
-			dev_err(cpu_dev, "Could not get nvmem cell: %ld\n",
-				PTR_ERR(speedbin_nvmem));
-		return PTR_ERR(speedbin_nvmem);
-	}
-
-	speedbin = nvmem_cell_read(speedbin_nvmem, &len);
-	nvmem_cell_put(speedbin_nvmem);
-	if (IS_ERR(speedbin))
-		return PTR_ERR(speedbin);
-
-	switch (msm8996_version) {
-	case MSM8996_V3:
-		versions = 1 << (unsigned int)(*speedbin);
-		break;
-	case MSM8996_SG:
-		versions = 1 << ((unsigned int)(*speedbin) + 4);
-		break;
-	default:
-		BUG();
-		break;
-	}
-	kfree(speedbin);
-
-	opp_tables = kcalloc(num_possible_cpus(), sizeof(*opp_tables), GFP_KERNEL);
-	if (!opp_tables)
-		return -ENOMEM;
-
-	for_each_possible_cpu(cpu) {
-		cpu_dev = get_cpu_device(cpu);
-		if (NULL == cpu_dev) {
-			ret = -ENODEV;
-			goto free_opp;
-		}
-
-		opp_tables[cpu] = dev_pm_opp_set_supported_hw(cpu_dev,
-							      &versions, 1);
-		if (IS_ERR(opp_tables[cpu])) {
-			ret = PTR_ERR(opp_tables[cpu]);
-			dev_err(cpu_dev, "Failed to set supported hardware\n");
-			goto free_opp;
-		}
-	}
-
-	cpufreq_dt_pdev = platform_device_register_simple("cpufreq-dt", -1,
-							  NULL, 0);
-	if (!IS_ERR(cpufreq_dt_pdev)) {
-		platform_set_drvdata(pdev, opp_tables);
-		return 0;
-	}
-
-	ret = PTR_ERR(cpufreq_dt_pdev);
-	dev_err(cpu_dev, "Failed to register platform device\n");
-
-free_opp:
-	for_each_possible_cpu(cpu) {
-		if (IS_ERR_OR_NULL(opp_tables[cpu]))
-			break;
-		dev_pm_opp_put_supported_hw(opp_tables[cpu]);
-	}
-	kfree(opp_tables);
-
-	return ret;
-}
-
-static int qcom_cpufreq_kryo_remove(struct platform_device *pdev)
-{
-	struct opp_table **opp_tables = platform_get_drvdata(pdev);
-	unsigned int cpu;
-
-	platform_device_unregister(cpufreq_dt_pdev);
-
-	for_each_possible_cpu(cpu)
-		dev_pm_opp_put_supported_hw(opp_tables[cpu]);
-
-	kfree(opp_tables);
-
-	return 0;
-}
-
-static struct platform_driver qcom_cpufreq_kryo_driver = {
-	.probe = qcom_cpufreq_kryo_probe,
-	.remove = qcom_cpufreq_kryo_remove,
-	.driver = {
-		.name = "qcom-cpufreq-kryo",
-	},
-};
-
-static const struct of_device_id qcom_cpufreq_kryo_match_list[] __initconst = {
-	{ .compatible = "qcom,apq8096", },
-	{ .compatible = "qcom,msm8996", },
-	{}
-};
-
-/*
- * Since the driver depends on smem and nvmem drivers, which may
- * return EPROBE_DEFER, all the real activity is done in the probe,
- * which may be defered as well. The init here is only registering
- * the driver and the platform device.
- */
-static int __init qcom_cpufreq_kryo_init(void)
-{
-	struct device_node *np = of_find_node_by_path("/");
-	const struct of_device_id *match;
-	int ret;
-
-	if (!np)
-		return -ENODEV;
-
-	match = of_match_node(qcom_cpufreq_kryo_match_list, np);
-	of_node_put(np);
-	if (!match)
-		return -ENODEV;
-
-	ret = platform_driver_register(&qcom_cpufreq_kryo_driver);
-	if (unlikely(ret < 0))
-		return ret;
-
-	kryo_cpufreq_pdev = platform_device_register_simple(
-		"qcom-cpufreq-kryo", -1, NULL, 0);
-	ret = PTR_ERR_OR_ZERO(kryo_cpufreq_pdev);
-	if (0 == ret)
-		return 0;
-
-	platform_driver_unregister(&qcom_cpufreq_kryo_driver);
-	return ret;
-}
-module_init(qcom_cpufreq_kryo_init);
-
-static void __exit qcom_cpufreq_kryo_exit(void)
-{
-	platform_device_unregister(kryo_cpufreq_pdev);
-	platform_driver_unregister(&qcom_cpufreq_kryo_driver);
-}
-module_exit(qcom_cpufreq_kryo_exit);
-
-MODULE_DESCRIPTION("Qualcomm Technologies, Inc. Kryo CPUfreq driver");
-MODULE_LICENSE("GPL v2");
--- /dev/null
+++ b/drivers/cpufreq/qcom-cpufreq-nvmem.c
@@ -0,0 +1,273 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (c) 2018, The Linux Foundation. All rights reserved.
+ */
+
+/*
+ * In Certain QCOM SoCs like apq8096 and msm8996 that have KRYO processors,
+ * the CPU frequency subset and voltage value of each OPP varies
+ * based on the silicon variant in use. Qualcomm Process Voltage Scaling Tables
+ * defines the voltage and frequency value based on the msm-id in SMEM
+ * and speedbin blown in the efuse combination.
+ * The qcom-cpufreq-nvmem driver reads the msm-id and efuse value from the SoC
+ * to provide the OPP framework with required information.
+ * This is used to determine the voltage and frequency value for each OPP of
+ * operating-points-v2 table when it is parsed by the OPP framework.
+ */
+
+#include <linux/cpu.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/platform_device.h>
+#include <linux/pm_opp.h>
+#include <linux/slab.h>
+#include <linux/soc/qcom/smem.h>
+
+#define MSM_ID_SMEM	137
+
+enum _msm_id {
+	MSM8996V3 = 0xF6ul,
+	APQ8096V3 = 0x123ul,
+	MSM8996SG = 0x131ul,
+	APQ8096SG = 0x138ul,
+};
+
+enum _msm8996_version {
+	MSM8996_V3,
+	MSM8996_SG,
+	NUM_OF_MSM8996_VERSIONS,
+};
+
+static struct platform_device *cpufreq_dt_pdev, *cpufreq_pdev;
+
+static enum _msm8996_version qcom_cpufreq_get_msm_id(void)
+{
+	size_t len;
+	u32 *msm_id;
+	enum _msm8996_version version;
+
+	msm_id = qcom_smem_get(QCOM_SMEM_HOST_ANY, MSM_ID_SMEM, &len);
+	if (IS_ERR(msm_id))
+		return NUM_OF_MSM8996_VERSIONS;
+
+	/* The first 4 bytes are format, next to them is the actual msm-id */
+	msm_id++;
+
+	switch ((enum _msm_id)*msm_id) {
+	case MSM8996V3:
+	case APQ8096V3:
+		version = MSM8996_V3;
+		break;
+	case MSM8996SG:
+	case APQ8096SG:
+		version = MSM8996_SG;
+		break;
+	default:
+		version = NUM_OF_MSM8996_VERSIONS;
+	}
+
+	return version;
+}
+
+static int qcom_cpufreq_kryo_name_version(struct device *cpu_dev,
+					  struct nvmem_cell *speedbin_nvmem,
+					  u32 *versions)
+{
+	size_t len;
+	u8 *speedbin;
+	enum _msm8996_version msm8996_version;
+
+	msm8996_version = qcom_cpufreq_get_msm_id();
+	if (NUM_OF_MSM8996_VERSIONS == msm8996_version) {
+		dev_err(cpu_dev, "Not Snapdragon 820/821!");
+		return -ENODEV;
+	}
+
+	speedbin = nvmem_cell_read(speedbin_nvmem, &len);
+	if (IS_ERR(speedbin))
+		return PTR_ERR(speedbin);
+
+	switch (msm8996_version) {
+	case MSM8996_V3:
+		*versions = 1 << (unsigned int)(*speedbin);
+		break;
+	case MSM8996_SG:
+		*versions = 1 << ((unsigned int)(*speedbin) + 4);
+		break;
+	default:
+		BUG();
+		break;
+	}
+
+	kfree(speedbin);
+	return 0;
+}
+
+static int qcom_cpufreq_probe(struct platform_device *pdev)
+{
+	struct opp_table **opp_tables;
+	int (*get_version)(struct device *cpu_dev,
+			   struct nvmem_cell *speedbin_nvmem,
+			   u32 *versions);
+	struct nvmem_cell *speedbin_nvmem;
+	struct device_node *np;
+	struct device *cpu_dev;
+	unsigned cpu;
+	u32 versions;
+	const struct of_device_id *match;
+	int ret;
+
+	cpu_dev = get_cpu_device(0);
+	if (!cpu_dev)
+		return -ENODEV;
+
+	match = pdev->dev.platform_data;
+	get_version = match->data;
+	if (!get_version)
+		return -ENODEV;
+
+	np = dev_pm_opp_of_get_opp_desc_node(cpu_dev);
+	if (!np)
+		return -ENOENT;
+
+	ret = of_device_is_compatible(np, "operating-points-v2-kryo-cpu");
+	if (!ret) {
+		of_node_put(np);
+		return -ENOENT;
+	}
+
+	speedbin_nvmem = of_nvmem_cell_get(np, NULL);
+	of_node_put(np);
+	if (IS_ERR(speedbin_nvmem)) {
+		if (PTR_ERR(speedbin_nvmem) != -EPROBE_DEFER)
+			dev_err(cpu_dev, "Could not get nvmem cell: %ld\n",
+				PTR_ERR(speedbin_nvmem));
+		return PTR_ERR(speedbin_nvmem);
+	}
+
+	ret = get_version(cpu_dev, speedbin_nvmem, &versions);
+	nvmem_cell_put(speedbin_nvmem);
+	if (ret)
+		return ret;
+
+	opp_tables = kcalloc(num_possible_cpus(), sizeof(*opp_tables), GFP_KERNEL);
+	if (!opp_tables)
+		return -ENOMEM;
+
+	for_each_possible_cpu(cpu) {
+		cpu_dev = get_cpu_device(cpu);
+		if (NULL == cpu_dev) {
+			ret = -ENODEV;
+			goto free_opp;
+		}
+
+		opp_tables[cpu] = dev_pm_opp_set_supported_hw(cpu_dev,
+							      &versions, 1);
+		if (IS_ERR(opp_tables[cpu])) {
+			ret = PTR_ERR(opp_tables[cpu]);
+			dev_err(cpu_dev, "Failed to set supported hardware\n");
+			goto free_opp;
+		}
+	}
+
+	cpufreq_dt_pdev = platform_device_register_simple("cpufreq-dt", -1,
+							  NULL, 0);
+	if (!IS_ERR(cpufreq_dt_pdev)) {
+		platform_set_drvdata(pdev, opp_tables);
+		return 0;
+	}
+
+	ret = PTR_ERR(cpufreq_dt_pdev);
+	dev_err(cpu_dev, "Failed to register platform device\n");
+
+free_opp:
+	for_each_possible_cpu(cpu) {
+		if (IS_ERR_OR_NULL(opp_tables[cpu]))
+			break;
+		dev_pm_opp_put_supported_hw(opp_tables[cpu]);
+	}
+	kfree(opp_tables);
+
+	return ret;
+}
+
+static int qcom_cpufreq_remove(struct platform_device *pdev)
+{
+	struct opp_table **opp_tables = platform_get_drvdata(pdev);
+	unsigned int cpu;
+
+	platform_device_unregister(cpufreq_dt_pdev);
+
+	for_each_possible_cpu(cpu)
+		dev_pm_opp_put_supported_hw(opp_tables[cpu]);
+
+	kfree(opp_tables);
+
+	return 0;
+}
+
+static struct platform_driver qcom_cpufreq_driver = {
+	.probe = qcom_cpufreq_probe,
+	.remove = qcom_cpufreq_remove,
+	.driver = {
+		.name = "qcom-cpufreq-nvmem",
+	},
+};
+
+static const struct of_device_id qcom_cpufreq_match_list[] __initconst = {
+	{ .compatible = "qcom,apq8096",
+	  .data = qcom_cpufreq_kryo_name_version },
+	{ .compatible = "qcom,msm8996",
+	  .data = qcom_cpufreq_kryo_name_version },
+	{},
+};
+
+/*
+ * Since the driver depends on smem and nvmem drivers, which may
+ * return EPROBE_DEFER, all the real activity is done in the probe,
+ * which may be defered as well. The init here is only registering
+ * the driver and the platform device.
+ */
+static int __init qcom_cpufreq_init(void)
+{
+	struct device_node *np = of_find_node_by_path("/");
+	const struct of_device_id *match;
+	int ret;
+
+	if (!np)
+		return -ENODEV;
+
+	match = of_match_node(qcom_cpufreq_match_list, np);
+	of_node_put(np);
+	if (!match)
+		return -ENODEV;
+
+	ret = platform_driver_register(&qcom_cpufreq_driver);
+	if (unlikely(ret < 0))
+		return ret;
+
+	cpufreq_pdev = platform_device_register_data(NULL, "qcom-cpufreq-nvmem",
+						     -1, match, sizeof(*match));
+	ret = PTR_ERR_OR_ZERO(cpufreq_pdev);
+	if (0 == ret)
+		return 0;
+
+	platform_driver_unregister(&qcom_cpufreq_driver);
+	return ret;
+}
+module_init(qcom_cpufreq_init);
+
+static void __exit qcom_cpufreq_exit(void)
+{
+	platform_device_unregister(cpufreq_pdev);
+	platform_driver_unregister(&qcom_cpufreq_driver);
+}
+module_exit(qcom_cpufreq_exit);
+
+MODULE_DESCRIPTION("Qualcomm Technologies, Inc. CPUfreq driver");
+MODULE_LICENSE("GPL v2");