[PATCH v3 1/5] rtc: mxc_rtc: Driver rework
Alexander Shiyan
shc_work at mail.ru
Sat Jun 29 04:40:40 EDT 2013
This patch rework mxc_rtc driver.
Major changes have been made:
- Added second clock support (optional) which permit module functionality.
- Implemented support for periodic interrupts.
- Some code have been optimized.
Signed-off-by: Alexander Shiyan <shc_work at mail.ru>
---
drivers/rtc/rtc-mxc.c | 278 +++++++++++++++++++++-----------------------------
1 file changed, 119 insertions(+), 159 deletions(-)
diff --git a/drivers/rtc/rtc-mxc.c b/drivers/rtc/rtc-mxc.c
index ab87bac..8ec47c8 100644
--- a/drivers/rtc/rtc-mxc.c
+++ b/drivers/rtc/rtc-mxc.c
@@ -12,7 +12,6 @@
#include <linux/io.h>
#include <linux/rtc.h>
#include <linux/module.h>
-#include <linux/slab.h>
#include <linux/interrupt.h>
#include <linux/platform_device.h>
#include <linux/clk.h>
@@ -39,20 +38,6 @@
#define RTC_ENABLE_BIT (1 << 7)
-#define MAX_PIE_NUM 9
-#define MAX_PIE_FREQ 512
-static const u32 PIE_BIT_DEF[MAX_PIE_NUM][2] = {
- { 2, RTC_2HZ_BIT },
- { 4, RTC_SAM0_BIT },
- { 8, RTC_SAM1_BIT },
- { 16, RTC_SAM2_BIT },
- { 32, RTC_SAM3_BIT },
- { 64, RTC_SAM4_BIT },
- { 128, RTC_SAM5_BIT },
- { 256, RTC_SAM6_BIT },
- { MAX_PIE_FREQ, RTC_SAM7_BIT },
-};
-
#define MXC_RTC_TIME 0
#define MXC_RTC_ALARM 1
@@ -66,9 +51,6 @@ static const u32 PIE_BIT_DEF[MAX_PIE_NUM][2] = {
#define RTC_STPWCH 0x1C /* 32bit rtc stopwatch min reg */
#define RTC_DAYR 0x20 /* 32bit rtc days counter reg */
#define RTC_DAYALARM 0x24 /* 32bit rtc day alarm reg */
-#define RTC_TEST1 0x28 /* 32bit rtc test reg 1 */
-#define RTC_TEST2 0x2C /* 32bit rtc test reg 2 */
-#define RTC_TEST3 0x30 /* 32bit rtc test reg 3 */
enum imx_rtc_type {
IMX1_RTC,
@@ -79,29 +61,12 @@ struct rtc_plat_data {
struct rtc_device *rtc;
void __iomem *ioaddr;
int irq;
- struct clk *clk;
- struct rtc_time g_rtc_alarm;
+ struct rtc_class_ops rtc_ops;
+ struct clk *clk_rtc;
+ struct clk *clk_ipg;
enum imx_rtc_type devtype;
};
-static struct platform_device_id imx_rtc_devtype[] = {
- {
- .name = "imx1-rtc",
- .driver_data = IMX1_RTC,
- }, {
- .name = "imx21-rtc",
- .driver_data = IMX21_RTC,
- }, {
- /* sentinel */
- }
-};
-MODULE_DEVICE_TABLE(platform, imx_rtc_devtype);
-
-static inline int is_imx1_rtc(struct rtc_plat_data *data)
-{
- return data->devtype == IMX1_RTC;
-}
-
/*
* This function is used to obtain the RTC time or the alarm value in
* second.
@@ -110,20 +75,16 @@ static u32 get_alarm_or_time(struct device *dev, int time_alarm)
{
struct platform_device *pdev = to_platform_device(dev);
struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
- void __iomem *ioaddr = pdata->ioaddr;
- u32 day = 0, hr = 0, min = 0, sec = 0, hr_min = 0;
-
- switch (time_alarm) {
- case MXC_RTC_TIME:
- day = readw(ioaddr + RTC_DAYR);
- hr_min = readw(ioaddr + RTC_HOURMIN);
- sec = readw(ioaddr + RTC_SECOND);
- break;
- case MXC_RTC_ALARM:
- day = readw(ioaddr + RTC_DAYALARM);
- hr_min = readw(ioaddr + RTC_ALRM_HM) & 0xffff;
- sec = readw(ioaddr + RTC_ALRM_SEC);
- break;
+ u32 day, hr, min, sec, hr_min;
+
+ if (time_alarm == MXC_RTC_TIME) {
+ day = readw(pdata->ioaddr + RTC_DAYR);
+ hr_min = readw(pdata->ioaddr + RTC_HOURMIN);
+ sec = readw(pdata->ioaddr + RTC_SECOND);
+ } else {
+ day = readw(pdata->ioaddr + RTC_DAYALARM);
+ hr_min = readw(pdata->ioaddr + RTC_ALRM_HM);
+ sec = readw(pdata->ioaddr + RTC_ALRM_SEC);
}
hr = hr_min >> 8;
@@ -140,7 +101,6 @@ static void set_alarm_or_time(struct device *dev, int time_alarm, u32 time)
u32 day, hr, min, sec, temp;
struct platform_device *pdev = to_platform_device(dev);
struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
- void __iomem *ioaddr = pdata->ioaddr;
day = time / 86400;
time -= day * 86400;
@@ -155,17 +115,14 @@ static void set_alarm_or_time(struct device *dev, int time_alarm, u32 time)
temp = (hr << 8) + min;
- switch (time_alarm) {
- case MXC_RTC_TIME:
- writew(day, ioaddr + RTC_DAYR);
- writew(sec, ioaddr + RTC_SECOND);
- writew(temp, ioaddr + RTC_HOURMIN);
- break;
- case MXC_RTC_ALARM:
- writew(day, ioaddr + RTC_DAYALARM);
- writew(sec, ioaddr + RTC_ALRM_SEC);
- writew(temp, ioaddr + RTC_ALRM_HM);
- break;
+ if (time_alarm == MXC_RTC_TIME) {
+ writew(day, pdata->ioaddr + RTC_DAYR);
+ writew(sec, pdata->ioaddr + RTC_SECOND);
+ writew(temp, pdata->ioaddr + RTC_HOURMIN);
+ } else {
+ writew(day, pdata->ioaddr + RTC_DAYALARM);
+ writew(sec, pdata->ioaddr + RTC_ALRM_SEC);
+ writew(temp, pdata->ioaddr + RTC_ALRM_HM);
}
}
@@ -179,7 +136,6 @@ static int rtc_update_alarm(struct device *dev, struct rtc_time *alrm)
unsigned long now, time;
struct platform_device *pdev = to_platform_device(dev);
struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
- void __iomem *ioaddr = pdata->ioaddr;
now = get_alarm_or_time(dev, MXC_RTC_TIME);
rtc_time_to_tm(now, &now_tm);
@@ -191,8 +147,9 @@ static int rtc_update_alarm(struct device *dev, struct rtc_time *alrm)
alarm_tm.tm_sec = alrm->tm_sec;
rtc_tm_to_time(&alarm_tm, &time);
- /* clear all the interrupt status bits */
- writew(readw(ioaddr + RTC_RTCISR), ioaddr + RTC_RTCISR);
+ /* clear interrupt status bit */
+ writew(RTC_ALM_BIT, pdata->ioaddr + RTC_RTCISR);
+
set_alarm_or_time(dev, MXC_RTC_ALARM, time);
return 0;
@@ -203,18 +160,19 @@ static void mxc_rtc_irq_enable(struct device *dev, unsigned int bit,
{
struct platform_device *pdev = to_platform_device(dev);
struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
- void __iomem *ioaddr = pdata->ioaddr;
u32 reg;
spin_lock_irq(&pdata->rtc->irq_lock);
- reg = readw(ioaddr + RTC_RTCIENR);
- if (enabled)
+ reg = readw(pdata->ioaddr + RTC_RTCIENR);
+ if (enabled) {
reg |= bit;
- else
+ /* Clear interrupt status */
+ writew(reg, pdata->ioaddr + RTC_RTCISR);
+ } else
reg &= ~bit;
+ writew(reg, pdata->ioaddr + RTC_RTCIENR);
- writew(reg, ioaddr + RTC_RTCIENR);
spin_unlock_irq(&pdata->rtc->irq_lock);
}
@@ -252,30 +210,42 @@ static irqreturn_t mxc_rtc_interrupt(int irq, void *dev_id)
return IRQ_HANDLED;
}
-/*
- * Clear all interrupts and release the IRQ
- */
-static void mxc_rtc_release(struct device *dev)
+static int mxc_rtc_open(struct device *dev)
{
struct platform_device *pdev = to_platform_device(dev);
struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
- void __iomem *ioaddr = pdata->ioaddr;
- spin_lock_irq(&pdata->rtc->irq_lock);
+ if (pdata->irq >= 0) {
+ unsigned long rate = clk_get_rate(pdata->clk_rtc);
- /* Disable all rtc interrupts */
- writew(0, ioaddr + RTC_RTCIENR);
+ pdata->rtc->max_user_freq = rate / 64;
+ rtc_irq_set_freq(pdata->rtc, NULL, rate / 64);
+ mxc_rtc_irq_enable(&pdev->dev, RTC_1HZ_BIT | RTC_SAM7_BIT, 1);
+ }
- /* Clear all interrupt status */
- writew(0xffffffff, ioaddr + RTC_RTCISR);
+ return 0;
+}
- spin_unlock_irq(&pdata->rtc->irq_lock);
+static void mxc_rtc_release(struct device *dev)
+{
+ struct platform_device *pdev = to_platform_device(dev);
+ struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
+
+ if (pdata->irq >= 0)
+ mxc_rtc_irq_enable(&pdev->dev, RTC_1HZ_BIT | RTC_SAM7_BIT, 0);
}
static int mxc_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
{
- mxc_rtc_irq_enable(dev, RTC_ALM_BIT, enabled);
- return 0;
+ struct platform_device *pdev = to_platform_device(dev);
+ struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
+
+ if (pdata->irq >= 0) {
+ mxc_rtc_irq_enable(dev, RTC_ALM_BIT, enabled);
+ return 0;
+ }
+
+ return -EINVAL;
}
/*
@@ -306,7 +276,7 @@ static int mxc_rtc_set_mmss(struct device *dev, unsigned long time)
/*
* TTC_DAYR register is 9-bit in MX1 SoC, save time and day of year only
*/
- if (is_imx1_rtc(pdata)) {
+ if (pdata->devtype == IMX1_RTC) {
struct rtc_time tm;
rtc_time_to_tm(time, &tm);
@@ -331,10 +301,9 @@ static int mxc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
{
struct platform_device *pdev = to_platform_device(dev);
struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
- void __iomem *ioaddr = pdata->ioaddr;
rtc_time_to_tm(get_alarm_or_time(dev, MXC_RTC_ALARM), &alrm->time);
- alrm->pending = ((readw(ioaddr + RTC_RTCISR) & RTC_ALM_BIT)) ? 1 : 0;
+ alrm->pending = !!(readw(pdata->ioaddr + RTC_RTCISR) & RTC_ALM_BIT);
return 0;
}
@@ -349,61 +318,41 @@ static int mxc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
int ret;
ret = rtc_update_alarm(dev, &alrm->time);
- if (ret)
- return ret;
+ if ((pdata->irq >= 0) && !ret)
+ mxc_rtc_irq_enable(dev, RTC_ALM_BIT, alrm->enabled);
- memcpy(&pdata->g_rtc_alarm, &alrm->time, sizeof(struct rtc_time));
- mxc_rtc_irq_enable(dev, RTC_ALM_BIT, alrm->enabled);
-
- return 0;
+ return ret;
}
-/* RTC layer */
-static struct rtc_class_ops mxc_rtc_ops = {
- .release = mxc_rtc_release,
- .read_time = mxc_rtc_read_time,
- .set_mmss = mxc_rtc_set_mmss,
- .read_alarm = mxc_rtc_read_alarm,
- .set_alarm = mxc_rtc_set_alarm,
- .alarm_irq_enable = mxc_rtc_alarm_irq_enable,
-};
-
static int mxc_rtc_probe(struct platform_device *pdev)
{
+ struct rtc_plat_data *pdata;
struct resource *res;
- struct rtc_device *rtc;
- struct rtc_plat_data *pdata = NULL;
u32 reg;
unsigned long rate;
int ret;
- res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
- if (!res)
- return -ENODEV;
-
pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
if (!pdata)
return -ENOMEM;
- pdata->devtype = pdev->id_entry->driver_data;
-
- if (!devm_request_mem_region(&pdev->dev, res->start,
- resource_size(res), pdev->name))
- return -EBUSY;
-
- pdata->ioaddr = devm_ioremap(&pdev->dev, res->start,
- resource_size(res));
-
- pdata->clk = devm_clk_get(&pdev->dev, NULL);
- if (IS_ERR(pdata->clk)) {
- dev_err(&pdev->dev, "unable to get clock!\n");
- ret = PTR_ERR(pdata->clk);
- goto exit_free_pdata;
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ pdata->ioaddr = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(pdata->ioaddr))
+ return PTR_ERR(pdata->ioaddr);
+
+ pdata->clk_rtc = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(pdata->clk_rtc)) {
+ dev_err(&pdev->dev, "Unable to get clock!\n");
+ return PTR_ERR(pdata->clk_rtc);
}
- clk_prepare_enable(pdata->clk);
- rate = clk_get_rate(pdata->clk);
+ pdata->clk_ipg = devm_clk_get(&pdev->dev, "ipg");
+ if (!IS_ERR(pdata->clk_ipg))
+ clk_prepare_enable(pdata->clk_ipg);
+ clk_prepare_enable(pdata->clk_rtc);
+ rate = clk_get_rate(pdata->clk_rtc);
if (rate == 32768)
reg = RTC_INPUT_CLK_32768HZ;
else if (rate == 32000)
@@ -411,49 +360,55 @@ static int mxc_rtc_probe(struct platform_device *pdev)
else if (rate == 38400)
reg = RTC_INPUT_CLK_38400HZ;
else {
- dev_err(&pdev->dev, "rtc clock is not valid (%lu)\n", rate);
+ dev_err(&pdev->dev, "RTC clock is not valid (%lu)\n", rate);
ret = -EINVAL;
goto exit_put_clk;
}
- reg |= RTC_ENABLE_BIT;
- writew(reg, (pdata->ioaddr + RTC_RTCCTL));
- if (((readw(pdata->ioaddr + RTC_RTCCTL)) & RTC_ENABLE_BIT) == 0) {
- dev_err(&pdev->dev, "hardware module can't be enabled!\n");
+ writew(reg | RTC_ENABLE_BIT, pdata->ioaddr + RTC_RTCCTL);
+ if (!(readw(pdata->ioaddr + RTC_RTCCTL) & RTC_ENABLE_BIT)) {
+ dev_err(&pdev->dev, "Hardware module can't be enabled!\n");
ret = -EIO;
goto exit_put_clk;
}
- platform_set_drvdata(pdev, pdata);
+ /* Disable all interrupts */
+ writew(0, pdata->ioaddr + RTC_RTCIENR);
- /* Configure and enable the RTC */
- pdata->irq = platform_get_irq(pdev, 0);
+ pdata->devtype = pdev->id_entry->driver_data;
+ platform_set_drvdata(pdev, pdata);
- if (pdata->irq >= 0 &&
- devm_request_irq(&pdev->dev, pdata->irq, mxc_rtc_interrupt,
- IRQF_SHARED, pdev->name, pdev) < 0) {
- dev_warn(&pdev->dev, "interrupt not available.\n");
- pdata->irq = -1;
+ pdata->rtc_ops.open = mxc_rtc_open;
+ pdata->rtc_ops.release = mxc_rtc_release;
+ pdata->rtc_ops.read_time = mxc_rtc_read_time;
+ pdata->rtc_ops.set_mmss = mxc_rtc_set_mmss;
+ pdata->rtc_ops.read_alarm = mxc_rtc_read_alarm;
+ pdata->rtc_ops.set_alarm = mxc_rtc_set_alarm;
+ pdata->rtc_ops.alarm_irq_enable = mxc_rtc_alarm_irq_enable;
+
+ pdata->rtc = devm_rtc_device_register(&pdev->dev, pdev->name,
+ &pdata->rtc_ops, THIS_MODULE);
+ if (IS_ERR(pdata->rtc)) {
+ ret = PTR_ERR(pdata->rtc);
+ goto exit_put_clk;
}
+ pdata->irq = platform_get_irq(pdev, 0);
if (pdata->irq >= 0)
- device_init_wakeup(&pdev->dev, 1);
+ if (devm_request_irq(&pdev->dev, pdata->irq, mxc_rtc_interrupt,
+ IRQF_SHARED, pdev->name, pdev) < 0) {
+ dev_warn(&pdev->dev, "Not using interrupt\n");
+ pdata->irq = -1;
+ }
- rtc = devm_rtc_device_register(&pdev->dev, pdev->name, &mxc_rtc_ops,
- THIS_MODULE);
- if (IS_ERR(rtc)) {
- ret = PTR_ERR(rtc);
- goto exit_put_clk;
- }
-
- pdata->rtc = rtc;
+ device_init_wakeup(&pdev->dev, pdata->irq >= 0);
return 0;
exit_put_clk:
- clk_disable_unprepare(pdata->clk);
-
-exit_free_pdata:
+ clk_disable_unprepare(pdata->clk_rtc);
+ if (!IS_ERR(pdata->clk_ipg))
+ clk_disable_unprepare(pdata->clk_ipg);
return ret;
}
@@ -462,13 +417,14 @@ static int mxc_rtc_remove(struct platform_device *pdev)
{
struct rtc_plat_data *pdata = platform_get_drvdata(pdev);
- clk_disable_unprepare(pdata->clk);
+ clk_disable_unprepare(pdata->clk_rtc);
+ if (!IS_ERR(pdata->clk_ipg))
+ clk_disable_unprepare(pdata->clk_ipg);
return 0;
}
-#ifdef CONFIG_PM_SLEEP
-static int mxc_rtc_suspend(struct device *dev)
+static int __maybe_unused mxc_rtc_suspend(struct device *dev)
{
struct rtc_plat_data *pdata = dev_get_drvdata(dev);
@@ -478,7 +434,7 @@ static int mxc_rtc_suspend(struct device *dev)
return 0;
}
-static int mxc_rtc_resume(struct device *dev)
+static int __maybe_unused mxc_rtc_resume(struct device *dev)
{
struct rtc_plat_data *pdata = dev_get_drvdata(dev);
@@ -487,24 +443,28 @@ static int mxc_rtc_resume(struct device *dev)
return 0;
}
-#endif
static SIMPLE_DEV_PM_OPS(mxc_rtc_pm_ops, mxc_rtc_suspend, mxc_rtc_resume);
+static const struct platform_device_id mxc_rtc_id_table[] = {
+ { .name = "imx1-rtc", .driver_data = IMX1_RTC, },
+ { .name = "imx21-rtc", .driver_data = IMX21_RTC, },
+ { }
+};
+MODULE_DEVICE_TABLE(platform, mxc_rtc_id_table);
+
static struct platform_driver mxc_rtc_driver = {
.driver = {
.name = "mxc_rtc",
.pm = &mxc_rtc_pm_ops,
.owner = THIS_MODULE,
},
- .id_table = imx_rtc_devtype,
+ .id_table = mxc_rtc_id_table,
.probe = mxc_rtc_probe,
.remove = mxc_rtc_remove,
};
-
module_platform_driver(mxc_rtc_driver)
MODULE_AUTHOR("Daniel Mack <daniel at caiaq.de>");
MODULE_DESCRIPTION("RTC driver for Freescale MXC");
MODULE_LICENSE("GPL");
-
--
1.8.1.5
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