[PATCH v6 12/17] ARM i.MX: Move i.MX pwm driver to pwm framework
Thierry Reding
thierry.reding at avionic-design.de
Tue Apr 10 11:06:35 EDT 2012
From: Sascha Hauer <s.hauer at pengutronix.de>
Move the driver to drivers/pwm/ and convert it to use the framework.
Signed-off-by: Sascha Hauer <s.hauer at pengutronix.de>
Signed-off-by: Thierry Reding <thierry.reding at avionic-design.de>
---
Changes in v5:
- adopt patch by Sascha Hauer to move i.MX driver to PWM framework
- rename to imx_pwm internally
arch/arm/plat-mxc/Kconfig | 6 -
arch/arm/plat-mxc/Makefile | 1 -
drivers/pwm/Kconfig | 9 ++
drivers/pwm/Makefile | 1 +
arch/arm/plat-mxc/pwm.c => drivers/pwm/pwm-imx.c | 182 +++++++++-------------
5 files changed, 81 insertions(+), 118 deletions(-)
rename arch/arm/plat-mxc/pwm.c => drivers/pwm/pwm-imx.c (58%)
diff --git a/arch/arm/plat-mxc/Kconfig b/arch/arm/plat-mxc/Kconfig
index c722f9c..baf9064 100644
--- a/arch/arm/plat-mxc/Kconfig
+++ b/arch/arm/plat-mxc/Kconfig
@@ -47,12 +47,6 @@ config MXC_TZIC
config MXC_AVIC
bool
-config MXC_PWM
- tristate "Enable PWM driver"
- select HAVE_PWM
- help
- Enable support for the i.MX PWM controller(s).
-
config MXC_DEBUG_BOARD
bool "Enable MXC debug board(for 3-stack)"
help
diff --git a/arch/arm/plat-mxc/Makefile b/arch/arm/plat-mxc/Makefile
index e81290c..46ba8de 100644
--- a/arch/arm/plat-mxc/Makefile
+++ b/arch/arm/plat-mxc/Makefile
@@ -11,7 +11,6 @@ obj-$(CONFIG_MXC_AVIC) += avic.o
obj-$(CONFIG_IMX_HAVE_IOMUX_V1) += iomux-v1.o
obj-$(CONFIG_ARCH_MXC_IOMUX_V3) += iomux-v3.o
obj-$(CONFIG_IRAM_ALLOC) += iram_alloc.o
-obj-$(CONFIG_MXC_PWM) += pwm.o
obj-$(CONFIG_MXC_ULPI) += ulpi.o
obj-$(CONFIG_MXC_USE_EPIT) += epit.o
obj-$(CONFIG_MXC_DEBUG_BOARD) += 3ds_debugboard.o
diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig
index 0ef4f30..a9a9715 100644
--- a/drivers/pwm/Kconfig
+++ b/drivers/pwm/Kconfig
@@ -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_IMX
+ tristate "i.MX pwm support"
+ depends on ARCH_MXC
+ help
+ Generic PWM framework driver for i.MX.
+
+ To compile this driver as a module, choose M here: the module
+ will be called pwm-imx.
+
config PWM_PXA
tristate "PXA PWM support"
depends on ARCH_PXA
diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
index e859c51..3dd1b83 100644
--- a/drivers/pwm/Makefile
+++ b/drivers/pwm/Makefile
@@ -1,4 +1,5 @@
obj-$(CONFIG_PWM) += core.o
obj-$(CONFIG_PWM_BFIN) += pwm-bfin.o
+obj-$(CONFIG_PWM_IMX) += pwm-imx.o
obj-$(CONFIG_PWM_PXA) += pwm-pxa.o
obj-$(CONFIG_PWM_TEGRA) += pwm-tegra.o
diff --git a/arch/arm/plat-mxc/pwm.c b/drivers/pwm/pwm-imx.c
similarity index 58%
rename from arch/arm/plat-mxc/pwm.c
rename to drivers/pwm/pwm-imx.c
index c0cab22..ef9c51b 100644
--- a/arch/arm/plat-mxc/pwm.c
+++ b/drivers/pwm/pwm-imx.c
@@ -39,33 +39,28 @@
#define MX3_PWMCR_CLKSRC_IPG (1 << 16)
#define MX3_PWMCR_EN (1 << 0)
-
-
-struct pwm_device {
- struct list_head node;
- struct platform_device *pdev;
-
- const char *label;
+struct imx_chip {
struct clk *clk;
int clk_enabled;
void __iomem *mmio_base;
- unsigned int use_count;
- unsigned int pwm_id;
+ struct pwm_chip chip;
};
-int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
+#define to_imx_chip(chip) container_of(chip, struct imx_chip, chip)
+
+static int imx_pwm_config(struct pwm_chip *chip,
+ struct pwm_device *pwm, int duty_ns, int period_ns)
{
- if (pwm == NULL || period_ns == 0 || duty_ns > period_ns)
- return -EINVAL;
+ struct imx_chip *imx = to_imx_chip(chip);
if (!(cpu_is_mx1() || cpu_is_mx21())) {
unsigned long long c;
unsigned long period_cycles, duty_cycles, prescale;
u32 cr;
- c = clk_get_rate(pwm->clk);
+ c = clk_get_rate(imx->clk);
c = c * period_ns;
do_div(c, 1000000000);
period_cycles = c;
@@ -86,8 +81,8 @@ int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
else
period_cycles = 0;
- writel(duty_cycles, pwm->mmio_base + MX3_PWMSAR);
- writel(period_cycles, pwm->mmio_base + MX3_PWMPR);
+ writel(duty_cycles, imx->mmio_base + MX3_PWMSAR);
+ writel(period_cycles, imx->mmio_base + MX3_PWMPR);
cr = MX3_PWMCR_PRESCALER(prescale) |
MX3_PWMCR_DOZEEN | MX3_PWMCR_WAITEN |
@@ -98,7 +93,7 @@ int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
else
cr |= MX3_PWMCR_CLKSRC_IPG_HIGH;
- writel(cr, pwm->mmio_base + MX3_PWMCR);
+ writel(cr, imx->mmio_base + MX3_PWMCR);
} else if (cpu_is_mx1() || cpu_is_mx21()) {
/* The PWM subsystem allows for exact frequencies. However,
* I cannot connect a scope on my device to the PWM line and
@@ -116,110 +111,72 @@ int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
* both the prescaler (/1 .. /128) and then by CLKSEL
* (/2 .. /16).
*/
- u32 max = readl(pwm->mmio_base + MX1_PWMP);
+ u32 max = readl(imx->mmio_base + MX1_PWMP);
u32 p = max * duty_ns / period_ns;
- writel(max - p, pwm->mmio_base + MX1_PWMS);
+ writel(max - p, imx->mmio_base + MX1_PWMS);
} else {
BUG();
}
return 0;
}
-EXPORT_SYMBOL(pwm_config);
-int pwm_enable(struct pwm_device *pwm)
+static int imx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
{
+ struct imx_chip *imx = to_imx_chip(chip);
int rc = 0;
- if (!pwm->clk_enabled) {
- rc = clk_prepare_enable(pwm->clk);
+ if (!imx->clk_enabled) {
+ rc = clk_prepare_enable(imx->clk);
if (!rc)
- pwm->clk_enabled = 1;
+ imx->clk_enabled = 1;
}
return rc;
}
-EXPORT_SYMBOL(pwm_enable);
-
-void pwm_disable(struct pwm_device *pwm)
-{
- writel(0, pwm->mmio_base + MX3_PWMCR);
-
- if (pwm->clk_enabled) {
- clk_disable_unprepare(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 imx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
{
- struct pwm_device *pwm;
- int found = 0;
+ struct imx_chip *imx = to_imx_chip(chip);
- mutex_lock(&pwm_lock);
+ writel(0, imx->mmio_base + MX3_PWMCR);
- list_for_each_entry(pwm, &pwm_list, node) {
- if (pwm->pwm_id == pwm_id) {
- found = 1;
- break;
- }
+ if (imx->clk_enabled) {
+ clk_disable_unprepare(imx->clk);
+ imx->clk_enabled = 0;
}
-
- 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 struct pwm_ops imx_pwm_ops = {
+ .enable = imx_pwm_enable,
+ .disable = imx_pwm_disable,
+ .config = imx_pwm_config,
+ .owner = THIS_MODULE,
+};
-static int __devinit mxc_pwm_probe(struct platform_device *pdev)
+static int __devinit imx_pwm_probe(struct platform_device *pdev)
{
- struct pwm_device *pwm;
+ struct imx_chip *imx;
struct resource *r;
int ret = 0;
- pwm = kzalloc(sizeof(struct pwm_device), GFP_KERNEL);
- if (pwm == NULL) {
+ imx = kzalloc(sizeof(*imx), GFP_KERNEL);
+ if (imx == NULL) {
dev_err(&pdev->dev, "failed to allocate memory\n");
return -ENOMEM;
}
- pwm->clk = clk_get(&pdev->dev, "pwm");
+ imx->clk = clk_get(&pdev->dev, "pwm");
- if (IS_ERR(pwm->clk)) {
- ret = PTR_ERR(pwm->clk);
+ if (IS_ERR(imx->clk)) {
+ ret = PTR_ERR(imx->clk);
goto err_free;
}
- pwm->clk_enabled = 0;
+ imx->chip.ops = &imx_pwm_ops;
+ imx->chip.base = -1;
+ imx->chip.npwm = 1;
- pwm->use_count = 0;
- pwm->pwm_id = pdev->id;
- pwm->pdev = pdev;
+ imx->clk_enabled = 0;
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
if (r == NULL) {
@@ -235,72 +192,75 @@ static int __devinit mxc_pwm_probe(struct platform_device *pdev)
goto err_free_clk;
}
- pwm->mmio_base = ioremap(r->start, resource_size(r));
- if (pwm->mmio_base == NULL) {
+ imx->mmio_base = ioremap(r->start, resource_size(r));
+ if (imx->mmio_base == NULL) {
dev_err(&pdev->dev, "failed to ioremap() registers\n");
ret = -ENODEV;
goto err_free_mem;
}
- mutex_lock(&pwm_lock);
- list_add_tail(&pwm->node, &pwm_list);
- mutex_unlock(&pwm_lock);
+ ret = pwmchip_add(&imx->chip);
+ if (ret)
+ goto err_iounmap;
- platform_set_drvdata(pdev, pwm);
+ platform_set_drvdata(pdev, imx);
return 0;
+err_iounmap:
+ iounmap(imx->mmio_base);
err_free_mem:
release_mem_region(r->start, resource_size(r));
err_free_clk:
- clk_put(pwm->clk);
+ clk_put(imx->clk);
err_free:
- kfree(pwm);
+ kfree(imx);
return ret;
}
-static int __devexit mxc_pwm_remove(struct platform_device *pdev)
+static int __devexit imx_pwm_remove(struct platform_device *pdev)
{
- struct pwm_device *pwm;
+ struct imx_chip *imx;
struct resource *r;
+ int ret;
- pwm = platform_get_drvdata(pdev);
- if (pwm == NULL)
+ imx = platform_get_drvdata(pdev);
+ if (imx == NULL)
return -ENODEV;
- mutex_lock(&pwm_lock);
- list_del(&pwm->node);
- mutex_unlock(&pwm_lock);
+ ret = pwmchip_remove(&imx->chip);
+ if (ret)
+ return ret;
- iounmap(pwm->mmio_base);
+ iounmap(imx->mmio_base);
r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
release_mem_region(r->start, resource_size(r));
- clk_put(pwm->clk);
+ clk_put(imx->clk);
- kfree(pwm);
+ kfree(imx);
return 0;
}
-static struct platform_driver mxc_pwm_driver = {
+static struct platform_driver imx_pwm_driver = {
.driver = {
.name = "mxc_pwm",
},
- .probe = mxc_pwm_probe,
- .remove = __devexit_p(mxc_pwm_remove),
+ .probe = imx_pwm_probe,
+ .remove = __devexit_p(imx_pwm_remove),
};
-static int __init mxc_pwm_init(void)
+static int __init imx_pwm_init(void)
{
- return platform_driver_register(&mxc_pwm_driver);
+ return platform_driver_register(&imx_pwm_driver);
}
-arch_initcall(mxc_pwm_init);
+arch_initcall(imx_pwm_init);
-static void __exit mxc_pwm_exit(void)
+static void __exit imx_pwm_exit(void)
{
- platform_driver_unregister(&mxc_pwm_driver);
+ platform_driver_unregister(&imx_pwm_driver);
}
-module_exit(mxc_pwm_exit);
+module_exit(imx_pwm_exit);
MODULE_LICENSE("GPL v2");
MODULE_AUTHOR("Sascha Hauer <s.hauer at pengutronix.de>");
--
1.7.9.6
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