Commit 17b2b478 authored by Thierry Reding's avatar Thierry Reding
Browse files

pwm: Move PXA PWM driver to PWM framework 



This commit moves the PXA PWM driver to the drivers/pwm subdirectory and
converts it to use the new PWM framework.

Signed-off-by: default avatarThierry Reding <thierry.reding@avionic-design.de>
parent a4315e3c

arch/arm/plat-pxa/Makefile

+0 −1
Original line number Diff line number Diff line
@@ -8,5 +8,4 @@ obj-$(CONFIG_PXA3xx) += mfp.o 
obj-$(CONFIG_PXA95x)		+= mfp.o

obj-$(CONFIG_ARCH_MMP)		+= mfp.o



obj-$(CONFIG_HAVE_PWM)		+= pwm.o

obj-$(CONFIG_PXA_SSP)		+= ssp.o

drivers/pwm/Kconfig

+9 −0
Original line number Diff line number Diff line
@@ -18,6 +18,15 @@ config PWM_BFIN 
	  To compile this driver as a module, choose M here: the module

	  will be called pwm-bfin.



config PWM_PXA

	tristate "PXA PWM support"

	depends on ARCH_PXA

	help

	  Generic PWM framework driver for PXA.



	  To compile this driver as a module, choose M here: the module

	  will be called pwm-pxa.



config PWM_TEGRA

	tristate "NVIDIA Tegra PWM support"

	depends on ARCH_TEGRA

drivers/pwm/Makefile

+1 −0
Original line number Diff line number Diff line 
obj-$(CONFIG_PWM)		+= core.o

obj-$(CONFIG_PWM_BFIN)		+= pwm-bfin.o

obj-$(CONFIG_PWM_PXA)		+= pwm-pxa.o

obj-$(CONFIG_PWM_TEGRA)		+= pwm-tegra.o

arch/arm/plat-pxa/pwm.c→drivers/pwm/pwm-pxa.c

+58 −114
Original line number Diff line number Diff line
@@ -43,33 +43,39 @@ MODULE_DEVICE_TABLE(platform, pwm_id_table); 
#define PWMCR_SD	(1 << 6)

#define PWMDCR_FD	(1 << 10)



struct pwm_device {

	struct list_head	node;

	struct pwm_device	*secondary;

	struct platform_device	*pdev;

struct pxa_pwm_chip {

	struct pwm_chip	chip;

	struct device	*dev;



	const char	*label;

	struct clk	*clk;

	int		clk_enabled;

	void __iomem	*mmio_base;



	unsigned int	use_count;

	unsigned int	pwm_id;

};



static inline struct pxa_pwm_chip *to_pxa_pwm_chip(struct pwm_chip *chip)

{

	return container_of(chip, struct pxa_pwm_chip, chip);

}



/*

 * period_ns = 10^9 * (PRESCALE + 1) * (PV + 1) / PWM_CLK_RATE

 * duty_ns   = 10^9 * (PRESCALE + 1) * DC / PWM_CLK_RATE

 */

int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)

static int pxa_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,

			  int duty_ns, int period_ns)

{

	struct pxa_pwm_chip *pc = to_pxa_pwm_chip(chip);

	unsigned long long c;

	unsigned long period_cycles, prescale, pv, dc;

	unsigned long offset;

	int rc;



	if (pwm == NULL || period_ns == 0 || duty_ns > period_ns)

	if (period_ns == 0 || duty_ns > period_ns)

		return -EINVAL;



	c = clk_get_rate(pwm->clk);

	offset = pwm->hwpwm ? 0x10 : 0;



	c = clk_get_rate(pc->clk);

	c = c * period_ns;

	do_div(c, 1000000000);

	period_cycles = c;
@@ -90,98 +96,56 @@ int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns) 
	/* NOTE: the clock to PWM has to be enabled first

	 * before writing to the registers

	 */

	clk_enable(pwm->clk);

	__raw_writel(prescale, pwm->mmio_base + PWMCR);

	__raw_writel(dc, pwm->mmio_base + PWMDCR);

	__raw_writel(pv, pwm->mmio_base + PWMPCR);

	clk_disable(pwm->clk);

	rc = clk_prepare_enable(pc->clk);

	if (rc < 0)

		return rc;



	writel(prescale, pc->mmio_base + offset + PWMCR);

	writel(dc, pc->mmio_base + offset + PWMDCR);

	writel(pv, pc->mmio_base + offset + PWMPCR);



	clk_disable_unprepare(pc->clk);

	return 0;

}

EXPORT_SYMBOL(pwm_config);



int pwm_enable(struct pwm_device *pwm)

static int pxa_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)

{

	struct pxa_pwm_chip *pc = to_pxa_pwm_chip(chip);

	int rc = 0;



	if (!pwm->clk_enabled) {

		rc = clk_enable(pwm->clk);

	if (!pc->clk_enabled) {

		rc = clk_prepare_enable(pc->clk);

		if (!rc)

			pwm->clk_enabled = 1;

			pc->clk_enabled++;

	}

	return rc;

}

EXPORT_SYMBOL(pwm_enable);



void pwm_disable(struct pwm_device *pwm)

{

	if (pwm->clk_enabled) {

		clk_disable(pwm->clk);

		pwm->clk_enabled = 0;

	}

}

EXPORT_SYMBOL(pwm_disable);



static DEFINE_MUTEX(pwm_lock);

static LIST_HEAD(pwm_list);



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

static void pxa_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)

{

	struct pwm_device *pwm;

	int found = 0;



	mutex_lock(&pwm_lock);

	struct pxa_pwm_chip *pc = to_pxa_pwm_chip(chip);



	list_for_each_entry(pwm, &pwm_list, node) {

		if (pwm->pwm_id == pwm_id) {

			found = 1;

			break;

	if (pc->clk_enabled) {

		clk_disable_unprepare(pc->clk);

		pc->clk_enabled--;

	}

}



	if (found) {

		if (pwm->use_count == 0) {

			pwm->use_count++;

			pwm->label = label;

		} else

			pwm = ERR_PTR(-EBUSY);

	} else

		pwm = ERR_PTR(-ENOENT);



	mutex_unlock(&pwm_lock);

	return pwm;

}

EXPORT_SYMBOL(pwm_request);



void pwm_free(struct pwm_device *pwm)

{

	mutex_lock(&pwm_lock);



	if (pwm->use_count) {

		pwm->use_count--;

		pwm->label = NULL;

	} else

		pr_warning("PWM device already freed\n");



	mutex_unlock(&pwm_lock);

}

EXPORT_SYMBOL(pwm_free);



static inline void __add_pwm(struct pwm_device *pwm)

{

	mutex_lock(&pwm_lock);

	list_add_tail(&pwm->node, &pwm_list);

	mutex_unlock(&pwm_lock);

}

static struct pwm_ops pxa_pwm_ops = {

	.config = pxa_pwm_config,

	.enable = pxa_pwm_enable,

	.disable = pxa_pwm_disable,

	.owner = THIS_MODULE,

};



static int __devinit pwm_probe(struct platform_device *pdev)

{

	const struct platform_device_id *id = platform_get_device_id(pdev);

	struct pwm_device *pwm, *secondary = NULL;

	struct pxa_pwm_chip *pwm;

	struct resource *r;

	int ret = 0;



	pwm = kzalloc(sizeof(struct pwm_device), GFP_KERNEL);

	pwm = kzalloc(sizeof(*pwm), GFP_KERNEL);

	if (pwm == NULL) {

		dev_err(&pdev->dev, "failed to allocate memory\n");

		return -ENOMEM;
@@ -194,9 +158,10 @@ static int __devinit pwm_probe(struct platform_device *pdev) 
	}

	pwm->clk_enabled = 0;



	pwm->use_count = 0;

	pwm->pwm_id = PWM_ID_BASE(id->driver_data) + pdev->id;

	pwm->pdev = pdev;

	pwm->chip.dev = &pdev->dev;

	pwm->chip.ops = &pxa_pwm_ops;

	pwm->chip.base = -1;

	pwm->chip.npwm = (id->driver_data & HAS_SECONDARY_PWM) ? 2 : 1;



	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	if (r == NULL) {
@@ -219,25 +184,12 @@ static int __devinit pwm_probe(struct platform_device *pdev) 
		goto err_free_mem;

	}



	if (id->driver_data & HAS_SECONDARY_PWM) {

		secondary = kzalloc(sizeof(struct pwm_device), GFP_KERNEL);

		if (secondary == NULL) {

			ret = -ENOMEM;

			goto err_free_mem;

		}



		*secondary = *pwm;

		pwm->secondary = secondary;



		/* registers for the second PWM has offset of 0x10 */

		secondary->mmio_base = pwm->mmio_base + 0x10;

		secondary->pwm_id = pdev->id + 2;

	ret = pwmchip_add(&pwm->chip);

	if (ret < 0) {

		dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret);

		return ret;

	}



	__add_pwm(pwm);

	if (secondary)

		__add_pwm(secondary);



	platform_set_drvdata(pdev, pwm);

	return 0;
@@ -252,30 +204,22 @@ static int __devinit pwm_probe(struct platform_device *pdev) 


static int __devexit pwm_remove(struct platform_device *pdev)

{

	struct pwm_device *pwm;

	struct pxa_pwm_chip *chip;

	struct resource *r;



	pwm = platform_get_drvdata(pdev);

	if (pwm == NULL)

	chip = platform_get_drvdata(pdev);

	if (chip == NULL)

		return -ENODEV;



	mutex_lock(&pwm_lock);

	pwmchip_remove(&chip->chip);



	if (pwm->secondary) {

		list_del(&pwm->secondary->node);

		kfree(pwm->secondary);

	}



	list_del(&pwm->node);

	mutex_unlock(&pwm_lock);



	iounmap(pwm->mmio_base);

	iounmap(chip->mmio_base);



	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);

	release_mem_region(r->start, resource_size(r));



	clk_put(pwm->clk);

	kfree(pwm);

	clk_put(chip->clk);

	kfree(chip);

	return 0;

}