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v3.1
  1/*
  2 * A driver for the RTC embedded in the Cirrus Logic EP93XX processors
  3 * Copyright (c) 2006 Tower Technologies
  4 *
  5 * Author: Alessandro Zummo <a.zummo@towertech.it>
  6 *
  7 * This program is free software; you can redistribute it and/or modify
  8 * it under the terms of the GNU General Public License version 2 as
  9 * published by the Free Software Foundation.
 10 */
 11
 12#include <linux/module.h>
 13#include <linux/rtc.h>
 14#include <linux/platform_device.h>
 15#include <linux/io.h>
 16#include <linux/gfp.h>
 17
 18#define EP93XX_RTC_DATA			0x000
 19#define EP93XX_RTC_MATCH		0x004
 20#define EP93XX_RTC_STATUS		0x008
 21#define  EP93XX_RTC_STATUS_INTR		 (1<<0)
 22#define EP93XX_RTC_LOAD			0x00C
 23#define EP93XX_RTC_CONTROL		0x010
 24#define  EP93XX_RTC_CONTROL_MIE		 (1<<0)
 25#define EP93XX_RTC_SWCOMP		0x108
 26#define  EP93XX_RTC_SWCOMP_DEL_MASK	 0x001f0000
 27#define  EP93XX_RTC_SWCOMP_DEL_SHIFT	 16
 28#define  EP93XX_RTC_SWCOMP_INT_MASK	 0x0000ffff
 29#define  EP93XX_RTC_SWCOMP_INT_SHIFT	 0
 30
 31#define DRV_VERSION "0.3"
 32
 33/*
 34 * struct device dev.platform_data is used to store our private data
 35 * because struct rtc_device does not have a variable to hold it.
 36 */
 37struct ep93xx_rtc {
 38	void __iomem	*mmio_base;
 39	struct rtc_device *rtc;
 40};
 41
 42static int ep93xx_rtc_get_swcomp(struct device *dev, unsigned short *preload,
 43				unsigned short *delete)
 44{
 45	struct ep93xx_rtc *ep93xx_rtc = dev->platform_data;
 46	unsigned long comp;
 47
 48	comp = __raw_readl(ep93xx_rtc->mmio_base + EP93XX_RTC_SWCOMP);
 49
 50	if (preload)
 51		*preload = (comp & EP93XX_RTC_SWCOMP_INT_MASK)
 52				>> EP93XX_RTC_SWCOMP_INT_SHIFT;
 53
 54	if (delete)
 55		*delete = (comp & EP93XX_RTC_SWCOMP_DEL_MASK)
 56				>> EP93XX_RTC_SWCOMP_DEL_SHIFT;
 57
 58	return 0;
 59}
 60
 61static int ep93xx_rtc_read_time(struct device *dev, struct rtc_time *tm)
 62{
 63	struct ep93xx_rtc *ep93xx_rtc = dev->platform_data;
 64	unsigned long time;
 65
 66	 time = __raw_readl(ep93xx_rtc->mmio_base + EP93XX_RTC_DATA);
 67
 68	rtc_time_to_tm(time, tm);
 69	return 0;
 70}
 71
 72static int ep93xx_rtc_set_mmss(struct device *dev, unsigned long secs)
 73{
 74	struct ep93xx_rtc *ep93xx_rtc = dev->platform_data;
 75
 76	__raw_writel(secs + 1, ep93xx_rtc->mmio_base + EP93XX_RTC_LOAD);
 77	return 0;
 78}
 79
 80static int ep93xx_rtc_proc(struct device *dev, struct seq_file *seq)
 81{
 82	unsigned short preload, delete;
 83
 84	ep93xx_rtc_get_swcomp(dev, &preload, &delete);
 85
 86	seq_printf(seq, "preload\t\t: %d\n", preload);
 87	seq_printf(seq, "delete\t\t: %d\n", delete);
 88
 89	return 0;
 90}
 91
 92static const struct rtc_class_ops ep93xx_rtc_ops = {
 93	.read_time	= ep93xx_rtc_read_time,
 94	.set_mmss	= ep93xx_rtc_set_mmss,
 95	.proc		= ep93xx_rtc_proc,
 96};
 97
 98static ssize_t ep93xx_rtc_show_comp_preload(struct device *dev,
 99			struct device_attribute *attr, char *buf)
100{
101	unsigned short preload;
102
103	ep93xx_rtc_get_swcomp(dev, &preload, NULL);
104
105	return sprintf(buf, "%d\n", preload);
106}
107static DEVICE_ATTR(comp_preload, S_IRUGO, ep93xx_rtc_show_comp_preload, NULL);
108
109static ssize_t ep93xx_rtc_show_comp_delete(struct device *dev,
110			struct device_attribute *attr, char *buf)
111{
112	unsigned short delete;
113
114	ep93xx_rtc_get_swcomp(dev, NULL, &delete);
115
116	return sprintf(buf, "%d\n", delete);
117}
118static DEVICE_ATTR(comp_delete, S_IRUGO, ep93xx_rtc_show_comp_delete, NULL);
119
120static struct attribute *ep93xx_rtc_attrs[] = {
121	&dev_attr_comp_preload.attr,
122	&dev_attr_comp_delete.attr,
123	NULL
124};
125
126static const struct attribute_group ep93xx_rtc_sysfs_files = {
127	.attrs	= ep93xx_rtc_attrs,
128};
129
130static int __init ep93xx_rtc_probe(struct platform_device *pdev)
131{
132	struct ep93xx_rtc *ep93xx_rtc;
133	struct resource *res;
134	int err;
135
136	ep93xx_rtc = devm_kzalloc(&pdev->dev, sizeof(*ep93xx_rtc), GFP_KERNEL);
137	if (!ep93xx_rtc)
138		return -ENOMEM;
139
140	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
141	if (!res)
142		return -ENXIO;
143
144	if (!devm_request_mem_region(&pdev->dev, res->start,
145				     resource_size(res), pdev->name))
146		return -EBUSY;
147
148	ep93xx_rtc->mmio_base = devm_ioremap(&pdev->dev, res->start,
149					     resource_size(res));
150	if (!ep93xx_rtc->mmio_base)
151		return -ENXIO;
152
153	pdev->dev.platform_data = ep93xx_rtc;
154	platform_set_drvdata(pdev, ep93xx_rtc);
155
156	ep93xx_rtc->rtc = rtc_device_register(pdev->name,
157				&pdev->dev, &ep93xx_rtc_ops, THIS_MODULE);
158	if (IS_ERR(ep93xx_rtc->rtc)) {
159		err = PTR_ERR(ep93xx_rtc->rtc);
160		goto exit;
161	}
162
163	err = sysfs_create_group(&pdev->dev.kobj, &ep93xx_rtc_sysfs_files);
164	if (err)
165		goto fail;
166
167	return 0;
168
169fail:
170	rtc_device_unregister(ep93xx_rtc->rtc);
171exit:
172	platform_set_drvdata(pdev, NULL);
173	pdev->dev.platform_data = NULL;
174	return err;
175}
176
177static int __exit ep93xx_rtc_remove(struct platform_device *pdev)
178{
179	struct ep93xx_rtc *ep93xx_rtc = platform_get_drvdata(pdev);
180
181	sysfs_remove_group(&pdev->dev.kobj, &ep93xx_rtc_sysfs_files);
182	platform_set_drvdata(pdev, NULL);
183	rtc_device_unregister(ep93xx_rtc->rtc);
184	pdev->dev.platform_data = NULL;
185
186	return 0;
187}
188
189/* work with hotplug and coldplug */
190MODULE_ALIAS("platform:ep93xx-rtc");
191
192static struct platform_driver ep93xx_rtc_driver = {
193	.driver		= {
194		.name	= "ep93xx-rtc",
195		.owner	= THIS_MODULE,
196	},
197	.remove		= __exit_p(ep93xx_rtc_remove),
 
198};
199
200static int __init ep93xx_rtc_init(void)
201{
202        return platform_driver_probe(&ep93xx_rtc_driver, ep93xx_rtc_probe);
203}
204
205static void __exit ep93xx_rtc_exit(void)
206{
207	platform_driver_unregister(&ep93xx_rtc_driver);
208}
209
210MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
211MODULE_DESCRIPTION("EP93XX RTC driver");
212MODULE_LICENSE("GPL");
213MODULE_VERSION(DRV_VERSION);
214
215module_init(ep93xx_rtc_init);
216module_exit(ep93xx_rtc_exit);
v3.5.6
  1/*
  2 * A driver for the RTC embedded in the Cirrus Logic EP93XX processors
  3 * Copyright (c) 2006 Tower Technologies
  4 *
  5 * Author: Alessandro Zummo <a.zummo@towertech.it>
  6 *
  7 * This program is free software; you can redistribute it and/or modify
  8 * it under the terms of the GNU General Public License version 2 as
  9 * published by the Free Software Foundation.
 10 */
 11
 12#include <linux/module.h>
 13#include <linux/rtc.h>
 14#include <linux/platform_device.h>
 15#include <linux/io.h>
 16#include <linux/gfp.h>
 17
 18#define EP93XX_RTC_DATA			0x000
 19#define EP93XX_RTC_MATCH		0x004
 20#define EP93XX_RTC_STATUS		0x008
 21#define  EP93XX_RTC_STATUS_INTR		 (1<<0)
 22#define EP93XX_RTC_LOAD			0x00C
 23#define EP93XX_RTC_CONTROL		0x010
 24#define  EP93XX_RTC_CONTROL_MIE		 (1<<0)
 25#define EP93XX_RTC_SWCOMP		0x108
 26#define  EP93XX_RTC_SWCOMP_DEL_MASK	 0x001f0000
 27#define  EP93XX_RTC_SWCOMP_DEL_SHIFT	 16
 28#define  EP93XX_RTC_SWCOMP_INT_MASK	 0x0000ffff
 29#define  EP93XX_RTC_SWCOMP_INT_SHIFT	 0
 30
 31#define DRV_VERSION "0.3"
 32
 33/*
 34 * struct device dev.platform_data is used to store our private data
 35 * because struct rtc_device does not have a variable to hold it.
 36 */
 37struct ep93xx_rtc {
 38	void __iomem	*mmio_base;
 39	struct rtc_device *rtc;
 40};
 41
 42static int ep93xx_rtc_get_swcomp(struct device *dev, unsigned short *preload,
 43				unsigned short *delete)
 44{
 45	struct ep93xx_rtc *ep93xx_rtc = dev->platform_data;
 46	unsigned long comp;
 47
 48	comp = __raw_readl(ep93xx_rtc->mmio_base + EP93XX_RTC_SWCOMP);
 49
 50	if (preload)
 51		*preload = (comp & EP93XX_RTC_SWCOMP_INT_MASK)
 52				>> EP93XX_RTC_SWCOMP_INT_SHIFT;
 53
 54	if (delete)
 55		*delete = (comp & EP93XX_RTC_SWCOMP_DEL_MASK)
 56				>> EP93XX_RTC_SWCOMP_DEL_SHIFT;
 57
 58	return 0;
 59}
 60
 61static int ep93xx_rtc_read_time(struct device *dev, struct rtc_time *tm)
 62{
 63	struct ep93xx_rtc *ep93xx_rtc = dev->platform_data;
 64	unsigned long time;
 65
 66	 time = __raw_readl(ep93xx_rtc->mmio_base + EP93XX_RTC_DATA);
 67
 68	rtc_time_to_tm(time, tm);
 69	return 0;
 70}
 71
 72static int ep93xx_rtc_set_mmss(struct device *dev, unsigned long secs)
 73{
 74	struct ep93xx_rtc *ep93xx_rtc = dev->platform_data;
 75
 76	__raw_writel(secs + 1, ep93xx_rtc->mmio_base + EP93XX_RTC_LOAD);
 77	return 0;
 78}
 79
 80static int ep93xx_rtc_proc(struct device *dev, struct seq_file *seq)
 81{
 82	unsigned short preload, delete;
 83
 84	ep93xx_rtc_get_swcomp(dev, &preload, &delete);
 85
 86	seq_printf(seq, "preload\t\t: %d\n", preload);
 87	seq_printf(seq, "delete\t\t: %d\n", delete);
 88
 89	return 0;
 90}
 91
 92static const struct rtc_class_ops ep93xx_rtc_ops = {
 93	.read_time	= ep93xx_rtc_read_time,
 94	.set_mmss	= ep93xx_rtc_set_mmss,
 95	.proc		= ep93xx_rtc_proc,
 96};
 97
 98static ssize_t ep93xx_rtc_show_comp_preload(struct device *dev,
 99			struct device_attribute *attr, char *buf)
100{
101	unsigned short preload;
102
103	ep93xx_rtc_get_swcomp(dev, &preload, NULL);
104
105	return sprintf(buf, "%d\n", preload);
106}
107static DEVICE_ATTR(comp_preload, S_IRUGO, ep93xx_rtc_show_comp_preload, NULL);
108
109static ssize_t ep93xx_rtc_show_comp_delete(struct device *dev,
110			struct device_attribute *attr, char *buf)
111{
112	unsigned short delete;
113
114	ep93xx_rtc_get_swcomp(dev, NULL, &delete);
115
116	return sprintf(buf, "%d\n", delete);
117}
118static DEVICE_ATTR(comp_delete, S_IRUGO, ep93xx_rtc_show_comp_delete, NULL);
119
120static struct attribute *ep93xx_rtc_attrs[] = {
121	&dev_attr_comp_preload.attr,
122	&dev_attr_comp_delete.attr,
123	NULL
124};
125
126static const struct attribute_group ep93xx_rtc_sysfs_files = {
127	.attrs	= ep93xx_rtc_attrs,
128};
129
130static int __devinit ep93xx_rtc_probe(struct platform_device *pdev)
131{
132	struct ep93xx_rtc *ep93xx_rtc;
133	struct resource *res;
134	int err;
135
136	ep93xx_rtc = devm_kzalloc(&pdev->dev, sizeof(*ep93xx_rtc), GFP_KERNEL);
137	if (!ep93xx_rtc)
138		return -ENOMEM;
139
140	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
141	if (!res)
142		return -ENXIO;
143
144	if (!devm_request_mem_region(&pdev->dev, res->start,
145				     resource_size(res), pdev->name))
146		return -EBUSY;
147
148	ep93xx_rtc->mmio_base = devm_ioremap(&pdev->dev, res->start,
149					     resource_size(res));
150	if (!ep93xx_rtc->mmio_base)
151		return -ENXIO;
152
153	pdev->dev.platform_data = ep93xx_rtc;
154	platform_set_drvdata(pdev, ep93xx_rtc);
155
156	ep93xx_rtc->rtc = rtc_device_register(pdev->name,
157				&pdev->dev, &ep93xx_rtc_ops, THIS_MODULE);
158	if (IS_ERR(ep93xx_rtc->rtc)) {
159		err = PTR_ERR(ep93xx_rtc->rtc);
160		goto exit;
161	}
162
163	err = sysfs_create_group(&pdev->dev.kobj, &ep93xx_rtc_sysfs_files);
164	if (err)
165		goto fail;
166
167	return 0;
168
169fail:
170	rtc_device_unregister(ep93xx_rtc->rtc);
171exit:
172	platform_set_drvdata(pdev, NULL);
173	pdev->dev.platform_data = NULL;
174	return err;
175}
176
177static int __devexit ep93xx_rtc_remove(struct platform_device *pdev)
178{
179	struct ep93xx_rtc *ep93xx_rtc = platform_get_drvdata(pdev);
180
181	sysfs_remove_group(&pdev->dev.kobj, &ep93xx_rtc_sysfs_files);
182	platform_set_drvdata(pdev, NULL);
183	rtc_device_unregister(ep93xx_rtc->rtc);
184	pdev->dev.platform_data = NULL;
185
186	return 0;
187}
188
 
 
 
189static struct platform_driver ep93xx_rtc_driver = {
190	.driver		= {
191		.name	= "ep93xx-rtc",
192		.owner	= THIS_MODULE,
193	},
194	.probe		= ep93xx_rtc_probe,
195	.remove		= __devexit_p(ep93xx_rtc_remove),
196};
197
198module_platform_driver(ep93xx_rtc_driver);
 
 
 
 
 
 
 
 
199
200MODULE_AUTHOR("Alessandro Zummo <a.zummo@towertech.it>");
201MODULE_DESCRIPTION("EP93XX RTC driver");
202MODULE_LICENSE("GPL");
203MODULE_VERSION(DRV_VERSION);
204MODULE_ALIAS("platform:ep93xx-rtc");