diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2014-06-08 22:31:16 +0400 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2014-06-08 22:31:16 +0400 |
commit | 3f17ea6dea8ba5668873afa54628a91aaa3fb1c0 (patch) | |
tree | afbeb2accd4c2199ddd705ae943995b143a0af02 /drivers/rtc/rtc-xgene.c | |
parent | 1860e379875dfe7271c649058aeddffe5afd9d0d (diff) | |
parent | 1a5700bc2d10cd379a795fd2bb377a190af5acd4 (diff) | |
download | linux-3f17ea6dea8ba5668873afa54628a91aaa3fb1c0.tar.xz |
Merge branch 'next' (accumulated 3.16 merge window patches) into master
Now that 3.15 is released, this merges the 'next' branch into 'master',
bringing us to the normal situation where my 'master' branch is the
merge window.
* accumulated work in next: (6809 commits)
ufs: sb mutex merge + mutex_destroy
powerpc: update comments for generic idle conversion
cris: update comments for generic idle conversion
idle: remove cpu_idle() forward declarations
nbd: zero from and len fields in NBD_CMD_DISCONNECT.
mm: convert some level-less printks to pr_*
MAINTAINERS: adi-buildroot-devel is moderated
MAINTAINERS: add linux-api for review of API/ABI changes
mm/kmemleak-test.c: use pr_fmt for logging
fs/dlm/debug_fs.c: replace seq_printf by seq_puts
fs/dlm/lockspace.c: convert simple_str to kstr
fs/dlm/config.c: convert simple_str to kstr
mm: mark remap_file_pages() syscall as deprecated
mm: memcontrol: remove unnecessary memcg argument from soft limit functions
mm: memcontrol: clean up memcg zoneinfo lookup
mm/memblock.c: call kmemleak directly from memblock_(alloc|free)
mm/mempool.c: update the kmemleak stack trace for mempool allocations
lib/radix-tree.c: update the kmemleak stack trace for radix tree allocations
mm: introduce kmemleak_update_trace()
mm/kmemleak.c: use %u to print ->checksum
...
Diffstat (limited to 'drivers/rtc/rtc-xgene.c')
-rw-r--r-- | drivers/rtc/rtc-xgene.c | 278 |
1 files changed, 278 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-xgene.c b/drivers/rtc/rtc-xgene.c new file mode 100644 index 000000000000..14129cc85bdb --- /dev/null +++ b/drivers/rtc/rtc-xgene.c @@ -0,0 +1,278 @@ +/* + * APM X-Gene SoC Real Time Clock Driver + * + * Copyright (c) 2014, Applied Micro Circuits Corporation + * Author: Rameshwar Prasad Sahu <rsahu@apm.com> + * Loc Ho <lho@apm.com> + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License as published by the + * Free Software Foundation; either version 2 of the License, or (at your + * option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + * + */ + +#include <linux/init.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/io.h> +#include <linux/slab.h> +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/rtc.h> + +/* RTC CSR Registers */ +#define RTC_CCVR 0x00 +#define RTC_CMR 0x04 +#define RTC_CLR 0x08 +#define RTC_CCR 0x0C +#define RTC_CCR_IE BIT(0) +#define RTC_CCR_MASK BIT(1) +#define RTC_CCR_EN BIT(2) +#define RTC_CCR_WEN BIT(3) +#define RTC_STAT 0x10 +#define RTC_STAT_BIT BIT(0) +#define RTC_RSTAT 0x14 +#define RTC_EOI 0x18 +#define RTC_VER 0x1C + +struct xgene_rtc_dev { + struct rtc_device *rtc; + struct device *dev; + unsigned long alarm_time; + void __iomem *csr_base; + struct clk *clk; + unsigned int irq_wake; +}; + +static int xgene_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct xgene_rtc_dev *pdata = dev_get_drvdata(dev); + + rtc_time_to_tm(readl(pdata->csr_base + RTC_CCVR), tm); + return rtc_valid_tm(tm); +} + +static int xgene_rtc_set_mmss(struct device *dev, unsigned long secs) +{ + struct xgene_rtc_dev *pdata = dev_get_drvdata(dev); + + /* + * NOTE: After the following write, the RTC_CCVR is only reflected + * after the update cycle of 1 seconds. + */ + writel((u32) secs, pdata->csr_base + RTC_CLR); + readl(pdata->csr_base + RTC_CLR); /* Force a barrier */ + + return 0; +} + +static int xgene_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct xgene_rtc_dev *pdata = dev_get_drvdata(dev); + + rtc_time_to_tm(pdata->alarm_time, &alrm->time); + alrm->enabled = readl(pdata->csr_base + RTC_CCR) & RTC_CCR_IE; + + return 0; +} + +static int xgene_rtc_alarm_irq_enable(struct device *dev, u32 enabled) +{ + struct xgene_rtc_dev *pdata = dev_get_drvdata(dev); + u32 ccr; + + ccr = readl(pdata->csr_base + RTC_CCR); + if (enabled) { + ccr &= ~RTC_CCR_MASK; + ccr |= RTC_CCR_IE; + } else { + ccr &= ~RTC_CCR_IE; + ccr |= RTC_CCR_MASK; + } + writel(ccr, pdata->csr_base + RTC_CCR); + + return 0; +} + +static int xgene_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm) +{ + struct xgene_rtc_dev *pdata = dev_get_drvdata(dev); + unsigned long rtc_time; + unsigned long alarm_time; + + rtc_time = readl(pdata->csr_base + RTC_CCVR); + rtc_tm_to_time(&alrm->time, &alarm_time); + + pdata->alarm_time = alarm_time; + writel((u32) pdata->alarm_time, pdata->csr_base + RTC_CMR); + + xgene_rtc_alarm_irq_enable(dev, alrm->enabled); + + return 0; +} + +static const struct rtc_class_ops xgene_rtc_ops = { + .read_time = xgene_rtc_read_time, + .set_mmss = xgene_rtc_set_mmss, + .read_alarm = xgene_rtc_read_alarm, + .set_alarm = xgene_rtc_set_alarm, + .alarm_irq_enable = xgene_rtc_alarm_irq_enable, +}; + +static irqreturn_t xgene_rtc_interrupt(int irq, void *id) +{ + struct xgene_rtc_dev *pdata = (struct xgene_rtc_dev *) id; + + /* Check if interrupt asserted */ + if (!(readl(pdata->csr_base + RTC_STAT) & RTC_STAT_BIT)) + return IRQ_NONE; + + /* Clear interrupt */ + readl(pdata->csr_base + RTC_EOI); + + rtc_update_irq(pdata->rtc, 1, RTC_IRQF | RTC_AF); + + return IRQ_HANDLED; +} + +static int xgene_rtc_probe(struct platform_device *pdev) +{ + struct xgene_rtc_dev *pdata; + struct resource *res; + int ret; + int irq; + + pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL); + if (!pdata) + return -ENOMEM; + platform_set_drvdata(pdev, pdata); + pdata->dev = &pdev->dev; + + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); + pdata->csr_base = devm_ioremap_resource(&pdev->dev, res); + if (IS_ERR(pdata->csr_base)) + return PTR_ERR(pdata->csr_base); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) { + dev_err(&pdev->dev, "No IRQ resource\n"); + return irq; + } + ret = devm_request_irq(&pdev->dev, irq, xgene_rtc_interrupt, 0, + dev_name(&pdev->dev), pdata); + if (ret) { + dev_err(&pdev->dev, "Could not request IRQ\n"); + return ret; + } + + pdata->clk = devm_clk_get(&pdev->dev, NULL); + if (IS_ERR(pdata->clk)) { + dev_err(&pdev->dev, "Couldn't get the clock for RTC\n"); + return -ENODEV; + } + clk_prepare_enable(pdata->clk); + + /* Turn on the clock and the crystal */ + writel(RTC_CCR_EN, pdata->csr_base + RTC_CCR); + + device_init_wakeup(&pdev->dev, 1); + + pdata->rtc = devm_rtc_device_register(&pdev->dev, pdev->name, + &xgene_rtc_ops, THIS_MODULE); + if (IS_ERR(pdata->rtc)) { + clk_disable_unprepare(pdata->clk); + return PTR_ERR(pdata->rtc); + } + + /* HW does not support update faster than 1 seconds */ + pdata->rtc->uie_unsupported = 1; + + return 0; +} + +static int xgene_rtc_remove(struct platform_device *pdev) +{ + struct xgene_rtc_dev *pdata = platform_get_drvdata(pdev); + + xgene_rtc_alarm_irq_enable(&pdev->dev, 0); + device_init_wakeup(&pdev->dev, 0); + clk_disable_unprepare(pdata->clk); + return 0; +} + +#ifdef CONFIG_PM_SLEEP +static int xgene_rtc_suspend(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct xgene_rtc_dev *pdata = platform_get_drvdata(pdev); + int irq; + + irq = platform_get_irq(pdev, 0); + if (device_may_wakeup(&pdev->dev)) { + if (!enable_irq_wake(irq)) + pdata->irq_wake = 1; + } else { + xgene_rtc_alarm_irq_enable(dev, 0); + clk_disable(pdata->clk); + } + + return 0; +} + +static int xgene_rtc_resume(struct device *dev) +{ + struct platform_device *pdev = to_platform_device(dev); + struct xgene_rtc_dev *pdata = platform_get_drvdata(pdev); + int irq; + + irq = platform_get_irq(pdev, 0); + if (device_may_wakeup(&pdev->dev)) { + if (pdata->irq_wake) { + disable_irq_wake(irq); + pdata->irq_wake = 0; + } + } else { + clk_enable(pdata->clk); + xgene_rtc_alarm_irq_enable(dev, 1); + } + + return 0; +} +#endif + +static SIMPLE_DEV_PM_OPS(xgene_rtc_pm_ops, xgene_rtc_suspend, xgene_rtc_resume); + +#ifdef CONFIG_OF +static const struct of_device_id xgene_rtc_of_match[] = { + {.compatible = "apm,xgene-rtc" }, + { } +}; +MODULE_DEVICE_TABLE(of, xgene_rtc_of_match); +#endif + +static struct platform_driver xgene_rtc_driver = { + .probe = xgene_rtc_probe, + .remove = xgene_rtc_remove, + .driver = { + .owner = THIS_MODULE, + .name = "xgene-rtc", + .pm = &xgene_rtc_pm_ops, + .of_match_table = of_match_ptr(xgene_rtc_of_match), + }, +}; + +module_platform_driver(xgene_rtc_driver); + +MODULE_DESCRIPTION("APM X-Gene SoC RTC driver"); +MODULE_AUTHOR("Rameshwar Sahu <rsahu@apm.com>"); +MODULE_LICENSE("GPL"); |