2 * TI PWM Subsystem driver
4 * Copyright (C) 2012 Texas Instruments Incorporated - http://www.ti.com/
6 * This program is free software; you can redistribute it and/or modify
7 * it under the terms of the GNU General Public License as published by
8 * the Free Software Foundation; either version 2 of the License, or
9 * (at your option) any later version.
11 * This program is distributed in the hope that it will be useful,
12 * but WITHOUT ANY WARRANTY; without even the implied warranty of
13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 * GNU General Public License for more details.
18 #include <linux/module.h>
19 #include <linux/platform_device.h>
21 #include <linux/err.h>
22 #include <linux/pm_runtime.h>
23 #include <linux/of_device.h>
25 #include "pwm-tipwmss.h"
27 #define PWMSS_CLKCONFIG 0x8 /* Clock gating reg */
28 #define PWMSS_CLKSTATUS 0xc /* Clock gating status reg */
31 void __iomem *mmio_base;
32 struct mutex pwmss_lock;
36 u16 pwmss_submodule_state_change(struct device *dev, int set)
38 struct pwmss_info *info = dev_get_drvdata(dev);
41 mutex_lock(&info->pwmss_lock);
42 val = readw(info->mmio_base + PWMSS_CLKCONFIG);
44 writew(val , info->mmio_base + PWMSS_CLKCONFIG);
45 mutex_unlock(&info->pwmss_lock);
47 return readw(info->mmio_base + PWMSS_CLKSTATUS);
49 EXPORT_SYMBOL(pwmss_submodule_state_change);
51 static const struct of_device_id pwmss_of_match[] = {
52 { .compatible = "ti,am33xx-pwmss" },
55 MODULE_DEVICE_TABLE(of, pwmss_of_match);
57 static int pwmss_probe(struct platform_device *pdev)
61 struct pwmss_info *info;
62 struct device_node *node = pdev->dev.of_node;
64 info = devm_kzalloc(&pdev->dev, sizeof(*info), GFP_KERNEL);
66 dev_err(&pdev->dev, "failed to allocate memory\n");
70 mutex_init(&info->pwmss_lock);
72 r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
74 dev_err(&pdev->dev, "no memory resource defined\n");
78 info->mmio_base = devm_ioremap_resource(&pdev->dev, r);
79 if (IS_ERR(info->mmio_base))
80 return PTR_ERR(info->mmio_base);
82 pm_runtime_enable(&pdev->dev);
83 pm_runtime_get_sync(&pdev->dev);
84 platform_set_drvdata(pdev, info);
86 /* Populate all the child nodes here... */
87 ret = of_platform_populate(node, NULL, NULL, &pdev->dev);
89 dev_err(&pdev->dev, "no child node found\n");
94 static int pwmss_remove(struct platform_device *pdev)
96 struct pwmss_info *info = platform_get_drvdata(pdev);
98 pm_runtime_put_sync(&pdev->dev);
99 pm_runtime_disable(&pdev->dev);
100 mutex_destroy(&info->pwmss_lock);
104 static int pwmss_suspend(struct device *dev)
106 struct pwmss_info *info = dev_get_drvdata(dev);
108 info->pwmss_clkconfig = readw(info->mmio_base + PWMSS_CLKCONFIG);
109 pm_runtime_put_sync(dev);
113 static int pwmss_resume(struct device *dev)
115 struct pwmss_info *info = dev_get_drvdata(dev);
117 pm_runtime_get_sync(dev);
118 writew(info->pwmss_clkconfig, info->mmio_base + PWMSS_CLKCONFIG);
122 static SIMPLE_DEV_PM_OPS(pwmss_pm_ops, pwmss_suspend, pwmss_resume);
124 static struct platform_driver pwmss_driver = {
127 .owner = THIS_MODULE,
129 .of_match_table = pwmss_of_match,
131 .probe = pwmss_probe,
132 .remove = pwmss_remove,
135 module_platform_driver(pwmss_driver);
137 MODULE_DESCRIPTION("PWM Subsystem driver");
138 MODULE_AUTHOR("Texas Instruments");
139 MODULE_LICENSE("GPL");