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Diffstat (limited to 'arch/arm/plat-pxa/pwm.c')
-rw-r--r--arch/arm/plat-pxa/pwm.c304
1 files changed, 0 insertions, 304 deletions
diff --git a/arch/arm/plat-pxa/pwm.c b/arch/arm/plat-pxa/pwm.c
deleted file mode 100644
index ef32686..0000000
--- a/arch/arm/plat-pxa/pwm.c
+++ /dev/null
@@ -1,304 +0,0 @@
-/*
- * linux/arch/arm/mach-pxa/pwm.c
- *
- * 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.
- *
- * 2008-02-13 initial version
- * 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 <asm/div64.h>
-
-#define HAS_SECONDARY_PWM 0x10
-#define PWM_ID_BASE(d) ((d) & 0xf)
-
-static const struct platform_device_id pwm_id_table[] = {
- /* PWM has_secondary_pwm? */
- { "pxa25x-pwm", 0 },
- { "pxa27x-pwm", 0 | HAS_SECONDARY_PWM },
- { "pxa168-pwm", 1 },
- { "pxa910-pwm", 1 },
- { },
-};
-MODULE_DEVICE_TABLE(platform, pwm_id_table);
-
-/* PWM registers and bits definitions */
-#define PWMCR (0x00)
-#define PWMDCR (0x04)
-#define PWMPCR (0x08)
-
-#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;
-
- const char *label;
- struct clk *clk;
- int clk_enabled;
- void __iomem *mmio_base;
-
- unsigned int use_count;
- unsigned int pwm_id;
-};
-
-/*
- * 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)
-{
- unsigned long long c;
- unsigned long period_cycles, prescale, pv, dc;
-
- if (pwm == NULL || period_ns == 0 || duty_ns > period_ns)
- return -EINVAL;
-
- c = clk_get_rate(pwm->clk);
- c = c * period_ns;
- do_div(c, 1000000000);
- period_cycles = c;
-
- if (period_cycles < 1)
- period_cycles = 1;
- prescale = (period_cycles - 1) / 1024;
- pv = period_cycles / (prescale + 1) - 1;
-
- if (prescale > 63)
- return -EINVAL;
-
- if (duty_ns == period_ns)
- dc = PWMDCR_FD;
- else
- dc = (pv + 1) * duty_ns / 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);
-
- return 0;
-}
-EXPORT_SYMBOL(pwm_config);
-
-int pwm_enable(struct pwm_device *pwm)
-{
- int rc = 0;
-
- if (!pwm->clk_enabled) {
- rc = clk_enable(pwm->clk);
- if (!rc)
- pwm->clk_enabled = 1;
- }
- 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)
-{
- 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)
-{
- const struct platform_device_id *id = platform_get_device_id(pdev);
- struct pwm_device *pwm, *secondary = NULL;
- 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, NULL);
- if (IS_ERR(pwm->clk)) {
- ret = PTR_ERR(pwm->clk);
- goto err_free;
- }
- pwm->clk_enabled = 0;
-
- pwm->use_count = 0;
- pwm->pwm_id = PWM_ID_BASE(id->driver_data) + 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;
- }
-
- 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;
- }
-
- __add_pwm(pwm);
- if (secondary)
- __add_pwm(secondary);
-
- 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 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);
-
- if (pwm->secondary) {
- list_del(&pwm->secondary->node);
- kfree(pwm->secondary);
- }
-
- 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 pwm_driver = {
- .driver = {
- .name = "pxa25x-pwm",
- .owner = THIS_MODULE,
- },
- .probe = pwm_probe,
- .remove = __devexit_p(pwm_remove),
- .id_table = pwm_id_table,
-};
-
-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 v2");