ARM i.MX: Move i.MX pwm driver to pwm framework
Move the driver to drivers/pwm/ and convert it to use the framework.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
[eric@eukrea.com: set chip.dev to prevent probe failure]
[eric@eukrea.com: fix pwmchip_add return code test]
Signed-off-by: Eric Bénard <eric@eukrea.com>
Signed-off-by: Thierry Reding <thierry.reding@avionic-design.de>
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_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-$(CONFIG_IMX_HAVE_IOMUX_V1) += iomux-v1.o
obj-$(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/arch/arm/plat-mxc/pwm.c b/arch/arm/plat-mxc/pwm.c
deleted file mode 100644
index c0cab22..0000000
--- a/arch/arm/plat-mxc/pwm.c
+++ /dev/null
@@ -1,306 +0,0 @@
-/*
- * simple driver for PWM (Pulse Width Modulator) controller
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * Derived from pxa PWM driver by eric miao <eric.miao@marvell.com>
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/platform_device.h>
-#include <linux/slab.h>
-#include <linux/err.h>
-#include <linux/clk.h>
-#include <linux/io.h>
-#include <linux/pwm.h>
-#include <mach/hardware.h>
-
-
-/* i.MX1 and i.MX21 share the same PWM function block: */
-
-#define MX1_PWMC 0x00 /* PWM Control Register */
-#define MX1_PWMS 0x04 /* PWM Sample Register */
-#define MX1_PWMP 0x08 /* PWM Period Register */
-
-
-/* i.MX27, i.MX31, i.MX35 share the same PWM function block: */
-
-#define MX3_PWMCR 0x00 /* PWM Control Register */
-#define MX3_PWMSAR 0x0C /* PWM Sample Register */
-#define MX3_PWMPR 0x10 /* PWM Period Register */
-#define MX3_PWMCR_PRESCALER(x) (((x - 1) & 0xFFF) << 4)
-#define MX3_PWMCR_DOZEEN (1 << 24)
-#define MX3_PWMCR_WAITEN (1 << 23)
-#define MX3_PWMCR_DBGEN (1 << 22)
-#define MX3_PWMCR_CLKSRC_IPG_HIGH (2 << 16)
-#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 clk *clk;
-
- int clk_enabled;
- void __iomem *mmio_base;
-
- unsigned int use_count;
- unsigned int pwm_id;
-};
-
-int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
-{
- if (pwm == NULL || period_ns == 0 || duty_ns > period_ns)
- return -EINVAL;
-
- 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 = c * period_ns;
- do_div(c, 1000000000);
- period_cycles = c;
-
- prescale = period_cycles / 0x10000 + 1;
-
- period_cycles /= prescale;
- c = (unsigned long long)period_cycles * duty_ns;
- do_div(c, period_ns);
- duty_cycles = c;
-
- /*
- * according to imx pwm RM, the real period value should be
- * PERIOD value in PWMPR plus 2.
- */
- if (period_cycles > 2)
- period_cycles -= 2;
- else
- period_cycles = 0;
-
- writel(duty_cycles, pwm->mmio_base + MX3_PWMSAR);
- writel(period_cycles, pwm->mmio_base + MX3_PWMPR);
-
- cr = MX3_PWMCR_PRESCALER(prescale) |
- MX3_PWMCR_DOZEEN | MX3_PWMCR_WAITEN |
- MX3_PWMCR_DBGEN | MX3_PWMCR_EN;
-
- if (cpu_is_mx25())
- cr |= MX3_PWMCR_CLKSRC_IPG;
- else
- cr |= MX3_PWMCR_CLKSRC_IPG_HIGH;
-
- writel(cr, pwm->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
- * thus cannot provide the program the PWM controller
- * exactly. Instead, I'm relying on the fact that the
- * Bootloader (u-boot or WinCE+haret) has programmed the PWM
- * function group already. So I'll just modify the PWM sample
- * register to follow the ratio of duty_ns vs. period_ns
- * accordingly.
- *
- * This is good enough for programming the brightness of
- * the LCD backlight.
- *
- * The real implementation would divide PERCLK[0] first by
- * both the prescaler (/1 .. /128) and then by CLKSEL
- * (/2 .. /16).
- */
- u32 max = readl(pwm->mmio_base + MX1_PWMP);
- u32 p = max * duty_ns / period_ns;
- writel(max - p, pwm->mmio_base + MX1_PWMS);
- } else {
- BUG();
- }
-
- return 0;
-}
-EXPORT_SYMBOL(pwm_config);
-
-int pwm_enable(struct pwm_device *pwm)
-{
- int rc = 0;
-
- if (!pwm->clk_enabled) {
- rc = clk_prepare_enable(pwm->clk);
- if (!rc)
- pwm->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)
-{
- struct pwm_device *pwm;
- int found = 0;
-
- mutex_lock(&pwm_lock);
-
- list_for_each_entry(pwm, &pwm_list, node) {
- if (pwm->pwm_id == pwm_id) {
- found = 1;
- break;
- }
- }
-
- 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 int __devinit mxc_pwm_probe(struct platform_device *pdev)
-{
- struct pwm_device *pwm;
- struct resource *r;
- int ret = 0;
-
- pwm = kzalloc(sizeof(struct pwm_device), GFP_KERNEL);
- if (pwm == NULL) {
- dev_err(&pdev->dev, "failed to allocate memory\n");
- return -ENOMEM;
- }
-
- pwm->clk = clk_get(&pdev->dev, "pwm");
-
- if (IS_ERR(pwm->clk)) {
- ret = PTR_ERR(pwm->clk);
- goto err_free;
- }
-
- pwm->clk_enabled = 0;
-
- pwm->use_count = 0;
- pwm->pwm_id = pdev->id;
- pwm->pdev = pdev;
-
- r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (r == NULL) {
- dev_err(&pdev->dev, "no memory resource defined\n");
- ret = -ENODEV;
- goto err_free_clk;
- }
-
- r = request_mem_region(r->start, resource_size(r), pdev->name);
- if (r == NULL) {
- dev_err(&pdev->dev, "failed to request memory resource\n");
- ret = -EBUSY;
- goto err_free_clk;
- }
-
- pwm->mmio_base = ioremap(r->start, resource_size(r));
- if (pwm->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);
-
- platform_set_drvdata(pdev, pwm);
- return 0;
-
-err_free_mem:
- release_mem_region(r->start, resource_size(r));
-err_free_clk:
- clk_put(pwm->clk);
-err_free:
- kfree(pwm);
- return ret;
-}
-
-static int __devexit mxc_pwm_remove(struct platform_device *pdev)
-{
- struct pwm_device *pwm;
- struct resource *r;
-
- pwm = platform_get_drvdata(pdev);
- if (pwm == NULL)
- return -ENODEV;
-
- mutex_lock(&pwm_lock);
- list_del(&pwm->node);
- mutex_unlock(&pwm_lock);
-
- iounmap(pwm->mmio_base);
-
- r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- release_mem_region(r->start, resource_size(r));
-
- clk_put(pwm->clk);
-
- kfree(pwm);
- return 0;
-}
-
-static struct platform_driver mxc_pwm_driver = {
- .driver = {
- .name = "mxc_pwm",
- },
- .probe = mxc_pwm_probe,
- .remove = __devexit_p(mxc_pwm_remove),
-};
-
-static int __init mxc_pwm_init(void)
-{
- return platform_driver_register(&mxc_pwm_driver);
-}
-arch_initcall(mxc_pwm_init);
-
-static void __exit mxc_pwm_exit(void)
-{
- platform_driver_unregister(&mxc_pwm_driver);
-}
-module_exit(mxc_pwm_exit);
-
-MODULE_LICENSE("GPL v2");
-MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
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 @@
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/drivers/pwm/pwm-imx.c b/drivers/pwm/pwm-imx.c
new file mode 100644
index 0000000..900d145
--- /dev/null
+++ b/drivers/pwm/pwm-imx.c
@@ -0,0 +1,267 @@
+/*
+ * simple driver for PWM (Pulse Width Modulator) controller
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Derived from pxa PWM driver by eric miao <eric.miao@marvell.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/pwm.h>
+#include <mach/hardware.h>
+
+
+/* i.MX1 and i.MX21 share the same PWM function block: */
+
+#define MX1_PWMC 0x00 /* PWM Control Register */
+#define MX1_PWMS 0x04 /* PWM Sample Register */
+#define MX1_PWMP 0x08 /* PWM Period Register */
+
+
+/* i.MX27, i.MX31, i.MX35 share the same PWM function block: */
+
+#define MX3_PWMCR 0x00 /* PWM Control Register */
+#define MX3_PWMSAR 0x0C /* PWM Sample Register */
+#define MX3_PWMPR 0x10 /* PWM Period Register */
+#define MX3_PWMCR_PRESCALER(x) (((x - 1) & 0xFFF) << 4)
+#define MX3_PWMCR_DOZEEN (1 << 24)
+#define MX3_PWMCR_WAITEN (1 << 23)
+#define MX3_PWMCR_DBGEN (1 << 22)
+#define MX3_PWMCR_CLKSRC_IPG_HIGH (2 << 16)
+#define MX3_PWMCR_CLKSRC_IPG (1 << 16)
+#define MX3_PWMCR_EN (1 << 0)
+
+struct imx_chip {
+ struct clk *clk;
+
+ int clk_enabled;
+ void __iomem *mmio_base;
+
+ struct pwm_chip chip;
+};
+
+#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)
+{
+ 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(imx->clk);
+ c = c * period_ns;
+ do_div(c, 1000000000);
+ period_cycles = c;
+
+ prescale = period_cycles / 0x10000 + 1;
+
+ period_cycles /= prescale;
+ c = (unsigned long long)period_cycles * duty_ns;
+ do_div(c, period_ns);
+ duty_cycles = c;
+
+ /*
+ * according to imx pwm RM, the real period value should be
+ * PERIOD value in PWMPR plus 2.
+ */
+ if (period_cycles > 2)
+ period_cycles -= 2;
+ else
+ period_cycles = 0;
+
+ 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 |
+ MX3_PWMCR_DBGEN | MX3_PWMCR_EN;
+
+ if (cpu_is_mx25())
+ cr |= MX3_PWMCR_CLKSRC_IPG;
+ else
+ cr |= MX3_PWMCR_CLKSRC_IPG_HIGH;
+
+ 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
+ * thus cannot provide the program the PWM controller
+ * exactly. Instead, I'm relying on the fact that the
+ * Bootloader (u-boot or WinCE+haret) has programmed the PWM
+ * function group already. So I'll just modify the PWM sample
+ * register to follow the ratio of duty_ns vs. period_ns
+ * accordingly.
+ *
+ * This is good enough for programming the brightness of
+ * the LCD backlight.
+ *
+ * The real implementation would divide PERCLK[0] first by
+ * both the prescaler (/1 .. /128) and then by CLKSEL
+ * (/2 .. /16).
+ */
+ u32 max = readl(imx->mmio_base + MX1_PWMP);
+ u32 p = max * duty_ns / period_ns;
+ writel(max - p, imx->mmio_base + MX1_PWMS);
+ } else {
+ BUG();
+ }
+
+ return 0;
+}
+
+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 (!imx->clk_enabled) {
+ rc = clk_prepare_enable(imx->clk);
+ if (!rc)
+ imx->clk_enabled = 1;
+ }
+ return rc;
+}
+
+static void imx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct imx_chip *imx = to_imx_chip(chip);
+
+ writel(0, imx->mmio_base + MX3_PWMCR);
+
+ if (imx->clk_enabled) {
+ clk_disable_unprepare(imx->clk);
+ imx->clk_enabled = 0;
+ }
+}
+
+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 imx_pwm_probe(struct platform_device *pdev)
+{
+ struct imx_chip *imx;
+ struct resource *r;
+ int ret = 0;
+
+ imx = kzalloc(sizeof(*imx), GFP_KERNEL);
+ if (imx == NULL) {
+ dev_err(&pdev->dev, "failed to allocate memory\n");
+ return -ENOMEM;
+ }
+
+ imx->clk = clk_get(&pdev->dev, "pwm");
+
+ if (IS_ERR(imx->clk)) {
+ ret = PTR_ERR(imx->clk);
+ goto err_free;
+ }
+
+ imx->chip.ops = &imx_pwm_ops;
+ imx->chip.dev = &pdev->dev;
+ imx->chip.base = -1;
+ imx->chip.npwm = 1;
+
+ imx->clk_enabled = 0;
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (r == NULL) {
+ dev_err(&pdev->dev, "no memory resource defined\n");
+ ret = -ENODEV;
+ goto err_free_clk;
+ }
+
+ r = request_mem_region(r->start, resource_size(r), pdev->name);
+ if (r == NULL) {
+ dev_err(&pdev->dev, "failed to request memory resource\n");
+ ret = -EBUSY;
+ goto err_free_clk;
+ }
+
+ 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;
+ }
+
+ ret = pwmchip_add(&imx->chip);
+ if (ret < 0)
+ goto err_iounmap;
+
+ 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(imx->clk);
+err_free:
+ kfree(imx);
+ return ret;
+}
+
+static int __devexit imx_pwm_remove(struct platform_device *pdev)
+{
+ struct imx_chip *imx;
+ struct resource *r;
+ int ret;
+
+ imx = platform_get_drvdata(pdev);
+ if (imx == NULL)
+ return -ENODEV;
+
+ ret = pwmchip_remove(&imx->chip);
+ if (ret)
+ return ret;
+
+ iounmap(imx->mmio_base);
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ release_mem_region(r->start, resource_size(r));
+
+ clk_put(imx->clk);
+
+ kfree(imx);
+ return 0;
+}
+
+static struct platform_driver imx_pwm_driver = {
+ .driver = {
+ .name = "mxc_pwm",
+ },
+ .probe = imx_pwm_probe,
+ .remove = __devexit_p(imx_pwm_remove),
+};
+
+static int __init imx_pwm_init(void)
+{
+ return platform_driver_register(&imx_pwm_driver);
+}
+arch_initcall(imx_pwm_init);
+
+static void __exit imx_pwm_exit(void)
+{
+ platform_driver_unregister(&imx_pwm_driver);
+}
+module_exit(imx_pwm_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");
