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| author | Alexandre Belloni <alexandre.belloni@free-electrons.com> | 2015-07-31 11:39:51 +0200 |
|---|---|---|
| committer | Alexandre Belloni <alexandre.belloni@free-electrons.com> | 2015-09-05 13:19:09 +0200 |
| commit | 11f67a8bbf65872c3e9edc70242420a8c314a860 (patch) | |
| tree | f0966bbef87cadd2292f4ae6bba0e05a531960eb | |
| parent | 202cc98acf96de1c3897194e1ed5ae1c80c8b0f3 (diff) | |
| download | linux-stable-11f67a8bbf65872c3e9edc70242420a8c314a860.tar.gz linux-stable-11f67a8bbf65872c3e9edc70242420a8c314a860.tar.bz2 linux-stable-11f67a8bbf65872c3e9edc70242420a8c314a860.zip | |
rtc: at91rm9200: get and use slow clock
Commit dca1a4b5ff6e ("clk: at91: keep slow clk enabled to prevent system
hang") added a workaround for the slow clock as it is not properly handled
by its users.
Get and use the slow clock as it is necessary for the at91rm9200 rtc.
Acked-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@free-electrons.com>
| -rw-r--r-- | drivers/rtc/rtc-at91rm9200.c | 27 |
1 files changed, 24 insertions, 3 deletions
diff --git a/drivers/rtc/rtc-at91rm9200.c b/drivers/rtc/rtc-at91rm9200.c index c4062d9f1bdd..cb62e214b52a 100644 --- a/drivers/rtc/rtc-at91rm9200.c +++ b/drivers/rtc/rtc-at91rm9200.c @@ -19,6 +19,7 @@ */ #include <linux/bcd.h> +#include <linux/clk.h> #include <linux/completion.h> #include <linux/interrupt.h> #include <linux/ioctl.h> @@ -59,6 +60,7 @@ static bool suspended; static DEFINE_SPINLOCK(suspended_lock); static unsigned long cached_events; static u32 at91_rtc_imr; +static struct clk *sclk; static void at91_rtc_write_ier(u32 mask) { @@ -407,6 +409,16 @@ static int __init at91_rtc_probe(struct platform_device *pdev) return -ENOMEM; } + sclk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(sclk)) + return PTR_ERR(sclk); + + ret = clk_prepare_enable(sclk); + if (ret) { + dev_err(&pdev->dev, "Could not enable slow clock\n"); + return ret; + } + at91_rtc_write(AT91_RTC_CR, 0); at91_rtc_write(AT91_RTC_MR, 0); /* 24 hour mode */ @@ -420,7 +432,7 @@ static int __init at91_rtc_probe(struct platform_device *pdev) "at91_rtc", pdev); if (ret) { dev_err(&pdev->dev, "IRQ %d already in use.\n", irq); - return ret; + goto err_clk; } /* cpu init code should really have flagged this device as @@ -431,8 +443,10 @@ static int __init at91_rtc_probe(struct platform_device *pdev) rtc = devm_rtc_device_register(&pdev->dev, pdev->name, &at91_rtc_ops, THIS_MODULE); - if (IS_ERR(rtc)) - return PTR_ERR(rtc); + if (IS_ERR(rtc)) { + ret = PTR_ERR(rtc); + goto err_clk; + } platform_set_drvdata(pdev, rtc); /* enable SECEV interrupt in order to initialize at91_rtc_upd_rdy @@ -442,6 +456,11 @@ static int __init at91_rtc_probe(struct platform_device *pdev) dev_info(&pdev->dev, "AT91 Real Time Clock driver.\n"); return 0; + +err_clk: + clk_disable_unprepare(sclk); + + return ret; } /* @@ -454,6 +473,8 @@ static int __exit at91_rtc_remove(struct platform_device *pdev) AT91_RTC_SECEV | AT91_RTC_TIMEV | AT91_RTC_CALEV); + clk_disable_unprepare(sclk); + return 0; } |