+++ /dev/null
-/*
- * arch/arm/mach-vt8500/pwm.c
- *
- * Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
- *
- * This software is licensed under the terms of the GNU General Public
- * License version 2, as published by the Free Software Foundation, and
- * may be copied, distributed, and modified under those terms.
- *
- * This program 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.
- */
-
-#include <linux/module.h>
-#include <linux/kernel.h>
-#include <linux/platform_device.h>
-#include <linux/slab.h>
-#include <linux/err.h>
-#include <linux/io.h>
-#include <linux/pwm.h>
-#include <linux/delay.h>
-
-#include <asm/div64.h>
-
-#define VT8500_NR_PWMS 4
-
-static DEFINE_MUTEX(pwm_lock);
-static LIST_HEAD(pwm_list);
-
-struct pwm_device {
- struct list_head node;
- struct platform_device *pdev;
-
- const char *label;
-
- void __iomem *regbase;
-
- unsigned int use_count;
- unsigned int pwm_id;
-};
-
-#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
-static inline void pwm_busy_wait(void __iomem *reg, u8 bitmask)
-{
- int loops = msecs_to_loops(10);
- while ((readb(reg) & bitmask) && --loops)
- cpu_relax();
-
- if (unlikely(!loops))
- pr_warning("Waiting for status bits 0x%x to clear timed out\n",
- bitmask);
-}
-
-int pwm_config(struct pwm_device *pwm, int duty_ns, int period_ns)
-{
- unsigned long long c;
- unsigned long period_cycles, prescale, pv, dc;
-
- if (pwm == NULL || period_ns == 0 || duty_ns > period_ns)
- return -EINVAL;
-
- c = 25000000/2; /* wild guess --- need to implement clocks */
- c = c * period_ns;
- do_div(c, 1000000000);
- period_cycles = c;
-
- if (period_cycles < 1)
- period_cycles = 1;
- prescale = (period_cycles - 1) / 4096;
- pv = period_cycles / (prescale + 1) - 1;
- if (pv > 4095)
- pv = 4095;
-
- if (prescale > 1023)
- return -EINVAL;
-
- c = (unsigned long long)pv * duty_ns;
- do_div(c, period_ns);
- dc = c;
-
- pwm_busy_wait(pwm->regbase + 0x40 + pwm->pwm_id, (1 << 1));
- writel(prescale, pwm->regbase + 0x4 + (pwm->pwm_id << 4));
-
- pwm_busy_wait(pwm->regbase + 0x40 + pwm->pwm_id, (1 << 2));
- writel(pv, pwm->regbase + 0x8 + (pwm->pwm_id << 4));
-
- pwm_busy_wait(pwm->regbase + 0x40 + pwm->pwm_id, (1 << 3));
- writel(dc, pwm->regbase + 0xc + (pwm->pwm_id << 4));
-
- return 0;
-}
-EXPORT_SYMBOL(pwm_config);
-
-int pwm_enable(struct pwm_device *pwm)
-{
- pwm_busy_wait(pwm->regbase + 0x40 + pwm->pwm_id, (1 << 0));
- writel(5, pwm->regbase + (pwm->pwm_id << 4));
- return 0;
-}
-EXPORT_SYMBOL(pwm_enable);
-
-void pwm_disable(struct pwm_device *pwm)
-{
- pwm_busy_wait(pwm->regbase + 0x40 + pwm->pwm_id, (1 << 0));
- writel(0, pwm->regbase + (pwm->pwm_id << 4));
-}
-EXPORT_SYMBOL(pwm_disable);
-
-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 inline void __add_pwm(struct pwm_device *pwm)
-{
- mutex_lock(&pwm_lock);
- list_add_tail(&pwm->node, &pwm_list);
- mutex_unlock(&pwm_lock);
-}
-
-static int __devinit pwm_probe(struct platform_device *pdev)
-{
- struct pwm_device *pwms;
- struct resource *r;
- int ret = 0;
- int i;
-
- pwms = kzalloc(sizeof(struct pwm_device) * VT8500_NR_PWMS, GFP_KERNEL);
- if (pwms == NULL) {
- dev_err(&pdev->dev, "failed to allocate memory\n");
- return -ENOMEM;
- }
-
- for (i = 0; i < VT8500_NR_PWMS; i++) {
- pwms[i].use_count = 0;
- pwms[i].pwm_id = i;
- pwms[i].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;
- }
-
- 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;
- }
-
- pwms[0].regbase = ioremap(r->start, resource_size(r));
- if (pwms[0].regbase == NULL) {
- dev_err(&pdev->dev, "failed to ioremap() registers\n");
- ret = -ENODEV;
- goto err_free_mem;
- }
-
- for (i = 1; i < VT8500_NR_PWMS; i++)
- pwms[i].regbase = pwms[0].regbase;
-
- for (i = 0; i < VT8500_NR_PWMS; i++)
- __add_pwm(&pwms[i]);
-
- platform_set_drvdata(pdev, pwms);
- return 0;
-
-err_free_mem:
- release_mem_region(r->start, resource_size(r));
-err_free:
- kfree(pwms);
- return ret;
-}
-
-static int __devexit pwm_remove(struct platform_device *pdev)
-{
- struct pwm_device *pwms;
- struct resource *r;
- int i;
-
- pwms = platform_get_drvdata(pdev);
- if (pwms == NULL)
- return -ENODEV;
-
- mutex_lock(&pwm_lock);
-
- for (i = 0; i < VT8500_NR_PWMS; i++)
- list_del(&pwms[i].node);
- mutex_unlock(&pwm_lock);
-
- iounmap(pwms[0].regbase);
-
- r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- release_mem_region(r->start, resource_size(r));
-
- kfree(pwms);
- return 0;
-}
-
-static struct platform_driver pwm_driver = {
- .driver = {
- .name = "vt8500-pwm",
- .owner = THIS_MODULE,
- },
- .probe = pwm_probe,
- .remove = __devexit_p(pwm_remove),
-};
-
-static int __init pwm_init(void)
-{
- return platform_driver_register(&pwm_driver);
-}
-arch_initcall(pwm_init);
-
-static void __exit pwm_exit(void)
-{
- platform_driver_unregister(&pwm_driver);
-}
-module_exit(pwm_exit);
-
-MODULE_LICENSE("GPL");
--- /dev/null
+/*
+ * arch/arm/mach-vt8500/pwm.c
+ *
+ * Copyright (C) 2010 Alexey Charkov <alchark@gmail.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program 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.
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/io.h>
+#include <linux/pwm.h>
+#include <linux/delay.h>
+
+#include <asm/div64.h>
+
+#define VT8500_NR_PWMS 4
+
+struct vt8500_chip {
+ struct pwm_chip chip;
+ void __iomem *base;
+};
+
+#define to_vt8500_chip(chip) container_of(chip, struct vt8500_chip, chip)
+
+#define msecs_to_loops(t) (loops_per_jiffy / 1000 * HZ * t)
+static inline void pwm_busy_wait(void __iomem *reg, u8 bitmask)
+{
+ int loops = msecs_to_loops(10);
+ while ((readb(reg) & bitmask) && --loops)
+ cpu_relax();
+
+ if (unlikely(!loops))
+ pr_warning("Waiting for status bits 0x%x to clear timed out\n",
+ bitmask);
+}
+
+static int vt8500_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm,
+ int duty_ns, int period_ns)
+{
+ struct vt8500_chip *vt8500 = to_vt8500_chip(chip);
+ unsigned long long c;
+ unsigned long period_cycles, prescale, pv, dc;
+
+ c = 25000000/2; /* wild guess --- need to implement clocks */
+ c = c * period_ns;
+ do_div(c, 1000000000);
+ period_cycles = c;
+
+ if (period_cycles < 1)
+ period_cycles = 1;
+ prescale = (period_cycles - 1) / 4096;
+ pv = period_cycles / (prescale + 1) - 1;
+ if (pv > 4095)
+ pv = 4095;
+
+ if (prescale > 1023)
+ return -EINVAL;
+
+ c = (unsigned long long)pv * duty_ns;
+ do_div(c, period_ns);
+ dc = c;
+
+ pwm_busy_wait(vt8500->base + 0x40 + pwm->hwpwm, (1 << 1));
+ writel(prescale, vt8500->base + 0x4 + (pwm->hwpwm << 4));
+
+ pwm_busy_wait(vt8500->base + 0x40 + pwm->hwpwm, (1 << 2));
+ writel(pv, vt8500->base + 0x8 + (pwm->hwpwm << 4));
+
+ pwm_busy_wait(vt8500->base + 0x40 + pwm->hwpwm, (1 << 3));
+ writel(dc, vt8500->base + 0xc + (pwm->hwpwm << 4));
+
+ return 0;
+}
+
+static int vt8500_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct vt8500_chip *vt8500 = to_vt8500_chip(chip);
+
+ pwm_busy_wait(vt8500->base + 0x40 + pwm->hwpwm, (1 << 0));
+ writel(5, vt8500->base + (pwm->hwpwm << 4));
+ return 0;
+}
+
+static void vt8500_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct vt8500_chip *vt8500 = to_vt8500_chip(chip);
+
+ pwm_busy_wait(vt8500->base + 0x40 + pwm->hwpwm, (1 << 0));
+ writel(0, vt8500->base + (pwm->hwpwm << 4));
+}
+
+static struct pwm_ops vt8500_pwm_ops = {
+ .enable = vt8500_pwm_enable,
+ .disable = vt8500_pwm_disable,
+ .config = vt8500_pwm_config,
+ .owner = THIS_MODULE,
+};
+
+static int __devinit pwm_probe(struct platform_device *pdev)
+{
+ struct vt8500_chip *chip;
+ struct resource *r;
+ int ret;
+
+ chip = kzalloc(sizeof(*chip), GFP_KERNEL);
+ if (chip == NULL) {
+ dev_err(&pdev->dev, "failed to allocate memory\n");
+ return -ENOMEM;
+ }
+
+ chip->chip.dev = &pdev->dev;
+ chip->chip.ops = &vt8500_pwm_ops;
+ chip->chip.base = -1;
+ chip->chip.npwm = VT8500_NR_PWMS;
+
+ 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;
+ }
+
+ 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;
+ }
+
+ chip->base = ioremap(r->start, resource_size(r));
+ if (chip->base == NULL) {
+ dev_err(&pdev->dev, "failed to ioremap() registers\n");
+ ret = -ENODEV;
+ goto err_free_mem;
+ }
+
+ ret = pwmchip_add(&chip->chip);
+ if (ret < 0)
+ goto err_unmap;
+
+ platform_set_drvdata(pdev, chip);
+ return ret;
+
+err_unmap:
+ iounmap(chip->base);
+err_free_mem:
+ release_mem_region(r->start, resource_size(r));
+err_free:
+ kfree(chip);
+ return ret;
+}
+
+static int __devexit pwm_remove(struct platform_device *pdev)
+{
+ struct vt8500_chip *chip;
+ struct resource *r;
+ int err;
+
+ chip = platform_get_drvdata(pdev);
+ if (chip == NULL)
+ return -ENODEV;
+
+ err = pwmchip_remove(&chip->chip);
+ if (err < 0)
+ return err;
+
+ iounmap(chip->base);
+
+ r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ release_mem_region(r->start, resource_size(r));
+
+ kfree(chip);
+ return 0;
+}
+
+static struct platform_driver pwm_driver = {
+ .driver = {
+ .name = "vt8500-pwm",
+ .owner = THIS_MODULE,
+ },
+ .probe = pwm_probe,
+ .remove = __devexit_p(pwm_remove),
+};
+
+static int __init pwm_init(void)
+{
+ return platform_driver_register(&pwm_driver);
+}
+arch_initcall(pwm_init);
+
+static void __exit pwm_exit(void)
+{
+ platform_driver_unregister(&pwm_driver);
+}
+module_exit(pwm_exit);
+
+MODULE_LICENSE("GPL");
projects / cascardo / linux.git / commitdiff