misc: Add ab8500 pwm driver (f0f05b1c) · Commits · e / devices / android_kernel_fairphone_FP4

drivers/mfd/ab8500-core.c

+12 −1

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		@@ -404,10 +404,21 @@ static struct mfd_cell ab8500_devs[] = {
		.num_resources = ARRAY_SIZE(ab8500_rtc_resources),
		.resources = ab8500_rtc_resources,
		},
		{
		.name = "ab8500-pwm",
		.id = 1,
		},
		{
		.name = "ab8500-pwm",
		.id = 2,
		},
		{
		.name = "ab8500-pwm",
		.id = 3,
		},
		{ .name = "ab8500-charger", },
		{ .name = "ab8500-audio", },
		{ .name = "ab8500-usb", },
		{ .name = "ab8500-pwm", },
		{ .name = "ab8500-regulator", },
		{
		.name = "ab8500-poweron-key",

drivers/misc/Kconfig

+9 −0

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		@@ -62,6 +62,15 @@ config ATMEL_PWM
		purposes including software controlled power-efficient backlights
		on LCD displays, motor control, and waveform generation.

		config AB8500_PWM
		bool "AB8500 PWM support"
		depends on AB8500_CORE
		select HAVE_PWM
		help
		This driver exports functions to enable/disble/config/free Pulse
		Width Modulation in the Analog Baseband Chip AB8500.
		It is used by led and backlight driver to control the intensity.

		config ATMEL_TCLIB
		bool "Atmel AT32/AT91 Timer/Counter Library"
		depends on (AVR32 \|\| ARCH_AT91)

drivers/misc/Makefile

+1 −0

Original line number	Diff line number	Diff line
		@@ -41,3 +41,4 @@ obj-$(CONFIG_VMWARE_BALLOON) += vmw_balloon.o
		obj-$(CONFIG_ARM_CHARLCD) += arm-charlcd.o
		obj-$(CONFIG_PCH_PHUB) += pch_phub.o
		obj-y += ti-st/
		obj-$(CONFIG_AB8500_PWM) += ab8500-pwm.o

drivers/misc/ab8500-pwm.c

0 → 100644

+168 −0

Original line number	Diff line number	Diff line
		/*
		* Copyright (C) ST-Ericsson SA 2010
		*
		* Author: Arun R Murthy <arun.murthy@stericsson.com>
		* License terms: GNU General Public License (GPL) version 2
		*/
		#include <linux/err.h>
		#include <linux/platform_device.h>
		#include <linux/slab.h>
		#include <linux/pwm.h>
		#include <linux/mfd/ab8500.h>
		#include <linux/mfd/abx500.h>

		/*
		* PWM Out generators
		* Bank: 0x10
		*/
		#define AB8500_PWM_OUT_CTRL1_REG 0x60
		#define AB8500_PWM_OUT_CTRL2_REG 0x61
		#define AB8500_PWM_OUT_CTRL7_REG 0x66

		/* backlight driver constants */
		#define ENABLE_PWM 1
		#define DISABLE_PWM 0

		struct pwm_device {
		struct device *dev;
		struct list_head node;
		const char *label;
		unsigned int pwm_id;
		};

		static LIST_HEAD(pwm_list);

		int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
		{
		int ret = 0;
		unsigned int higher_val, lower_val;
		u8 reg;

		/*
		* get the first 8 bits that are be written to
		* AB8500_PWM_OUT_CTRL1_REG[0:7]
		*/
		lower_val = duty_ns & 0x00FF;
		/*
		* get bits [9:10] that are to be written to
		* AB8500_PWM_OUT_CTRL2_REG[0:1]
		*/
		higher_val = ((duty_ns & 0x0300) >> 8);

		reg = AB8500_PWM_OUT_CTRL1_REG + ((pwm->pwm_id - 1) * 2);

		ret = abx500_set_register_interruptible(pwm->dev, AB8500_MISC,
		reg, (u8)lower_val);
		if (ret < 0)
		return ret;
		ret = abx500_set_register_interruptible(pwm->dev, AB8500_MISC,
		(reg + 1), (u8)higher_val);

		return ret;
		}
		EXPORT_SYMBOL(pwm_config);

		int pwm_enable(struct pwm_device *pwm)
		{
		int ret;

		ret = abx500_mask_and_set_register_interruptible(pwm->dev,
		AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
		1 << (pwm->pwm_id-1), ENABLE_PWM);
		if (ret < 0)
		dev_err(pwm->dev, "%s: Failed to disable PWM, Error %d\n",
		pwm->label, ret);
		return ret;
		}
		EXPORT_SYMBOL(pwm_enable);

		void pwm_disable(struct pwm_device *pwm)
		{
		int ret;

		ret = abx500_mask_and_set_register_interruptible(pwm->dev,
		AB8500_MISC, AB8500_PWM_OUT_CTRL7_REG,
		1 << (pwm->pwm_id-1), DISABLE_PWM);
		if (ret < 0)
		dev_err(pwm->dev, "%s: Failed to disable PWM, Error %d\n",
		pwm->label, ret);
		return;
		}
		EXPORT_SYMBOL(pwm_disable);

		struct pwm_device pwm_request(int pwm_id, const char label)
		{
		struct pwm_device *pwm;

		list_for_each_entry(pwm, &pwm_list, node) {
		if (pwm->pwm_id == pwm_id) {
		pwm->label = label;
		pwm->pwm_id = pwm_id;
		return pwm;
		}
		}

		return ERR_PTR(-ENOENT);
		}
		EXPORT_SYMBOL(pwm_request);

		void pwm_free(struct pwm_device *pwm)
		{
		pwm_disable(pwm);
		}
		EXPORT_SYMBOL(pwm_free);

		static int __devinit ab8500_pwm_probe(struct platform_device *pdev)
		{
		struct pwm_device *pwm;
		/*
		* Nothing to be done in probe, this is required to get the
		* device which is required for ab8500 read and write
		*/
		pwm = kzalloc(sizeof(struct pwm_device), GFP_KERNEL);
		if (pwm == NULL) {
		dev_err(&pdev->dev, "failed to allocate memory\n");
		return -ENOMEM;
		}
		pwm->dev = &pdev->dev;
		pwm->pwm_id = pdev->id;
		list_add_tail(&pwm->node, &pwm_list);
		platform_set_drvdata(pdev, pwm);
		dev_dbg(pwm->dev, "pwm probe successful\n");
		return 0;
		}

		static int __devexit ab8500_pwm_remove(struct platform_device *pdev)
		{
		struct pwm_device *pwm = platform_get_drvdata(pdev);
		list_del(&pwm->node);
		dev_dbg(&pdev->dev, "pwm driver removed\n");
		kfree(pwm);
		return 0;
		}

		static struct platform_driver ab8500_pwm_driver = {
		.driver = {
		.name = "ab8500-pwm",
		.owner = THIS_MODULE,
		},
		.probe = ab8500_pwm_probe,
		.remove = __devexit_p(ab8500_pwm_remove),
		};

		static int __init ab8500_pwm_init(void)
		{
		return platform_driver_register(&ab8500_pwm_driver);
		}

		static void __exit ab8500_pwm_exit(void)
		{
		platform_driver_unregister(&ab8500_pwm_driver);
		}

		subsys_initcall(ab8500_pwm_init);
		module_exit(ab8500_pwm_exit);
		MODULE_AUTHOR("Arun MURTHY <arun.murthy@stericsson.com>");
		MODULE_DESCRIPTION("AB8500 Pulse Width Modulation Driver");
		MODULE_ALIAS("AB8500 PWM driver");
		MODULE_LICENSE("GPL v2");