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| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-19 10:09:22 -0700 |
| commit | f4cdf7ca9a1fdcca413157df19753f388a5a224e (patch) | |
| tree | 60a31895b2446cd7fa27514e8c2843534a0de0da /drivers/rtc/rtc-ds1216.c | |
| download | linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.tar.gz linux-stable-f4cdf7ca9a1fdcca413157df19753f388a5a224e.zip | |
Merge tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-mediagrafted
Pull media updates from Mauro Carvalho Chehab:
- v4l2-core: added ISP statistics support and per-block validation
- v4l2-core: Allow unknown HDR10 white point and luminance
- New camera sensors: Sony IMX678 and IMX471m, Himax HM1092 IR sensor
- New codec: Milos: VPU v2.0 codec support
- isp driver: gained support for Dreamchip RPPX1 ISP framework
- vsp1 driver: gained support for RZ/T2H and RZ/N2H
- Novalake driver: gained CVS support for new NVL hardware
- dvb-core: fix feed leak on failed DMX_ADD_PID
- several driver fixes, cleanups and minor improvements
* tag 'media/v7.3-1' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (308 commits)
media: ipu-bridge: check all DMI entries when overriding sensor rotation
media: v4l2-async: avoid deleting unlinked ASC entry on link error
media: rzg2l-cru: Align bytesperline to hardware DMA stride requirement
media: intel/ipu6: fix async notifier cleanup leak on parse error
media: staging/ipu7: fix async notifier UAF on probe error path
media: amd: isp4: fix self-deadlock in isp4sd_pwron_and_init() error path
media: amd: isp4: release partial allocations in isp4if_alloc_fw_gpumem()
media: rcar-isp: Fix VSPX reference leaks
media: rcar-isp: Release ISPCORE resources
media: i2c: imx415: Release runtime PM reference on VBLANK error
media: i2c: imx415: Return test pattern write errors
media: renesas: vsp1: Declare index variables in for loop statement
media: renesas: vsp1: Make reset control optional to support platforms without a reset line
media: dt-bindings: media: renesas,vsp1: Document RZ/T2H and RZ/N2H SoCs
media: dt-bindings: media: renesas,fcp: Document RZ/T2H and RZ/N2H SoCs
media: nxp: imx8-isi: Add additional 32-bit RGB format support
media: nxp: imx8-isi: Add 16-bit raw Bayer format support
media: nxp: imx8-isi: Implement per-stream reference counting for multiplexed streams
media: nxp: imx8-isi: Use BIT_ULL() for 64-bit stream masks
media: nxp: imx8-isi: Correct color map between V4L2 and ISI
...
Diffstat (limited to 'drivers/rtc/rtc-ds1216.c')
| -rw-r--r-- | drivers/rtc/rtc-ds1216.c | 174 |
1 files changed, 174 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-ds1216.c b/drivers/rtc/rtc-ds1216.c new file mode 100644 index 000000000..7eeb3f359 --- /dev/null +++ b/drivers/rtc/rtc-ds1216.c @@ -0,0 +1,174 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Dallas DS1216 RTC driver + * + * Copyright (c) 2007 Thomas Bogendoerfer + * + */ + +#include <linux/module.h> +#include <linux/rtc.h> +#include <linux/platform_device.h> +#include <linux/bcd.h> +#include <linux/slab.h> + +struct ds1216_regs { + u8 tsec; + u8 sec; + u8 min; + u8 hour; + u8 wday; + u8 mday; + u8 month; + u8 year; +}; + +#define DS1216_HOUR_1224 (1 << 7) +#define DS1216_HOUR_AMPM (1 << 5) + +struct ds1216_priv { + struct rtc_device *rtc; + void __iomem *ioaddr; +}; + +static const u8 magic[] = { + 0xc5, 0x3a, 0xa3, 0x5c, 0xc5, 0x3a, 0xa3, 0x5c +}; + +/* + * Read the 64 bit we'd like to have - It a series + * of 64 bits showing up in the LSB of the base register. + * + */ +static void ds1216_read(u8 __iomem *ioaddr, u8 *buf) +{ + unsigned char c; + int i, j; + + for (i = 0; i < 8; i++) { + c = 0; + for (j = 0; j < 8; j++) + c |= (readb(ioaddr) & 0x1) << j; + buf[i] = c; + } +} + +static void ds1216_write(u8 __iomem *ioaddr, const u8 *buf) +{ + unsigned char c; + int i, j; + + for (i = 0; i < 8; i++) { + c = buf[i]; + for (j = 0; j < 8; j++) { + writeb(c, ioaddr); + c = c >> 1; + } + } +} + +static void ds1216_switch_ds_to_clock(u8 __iomem *ioaddr) +{ + /* Reset magic pointer */ + readb(ioaddr); + /* Write 64 bit magic to DS1216 */ + ds1216_write(ioaddr, magic); +} + +static int ds1216_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct ds1216_priv *priv = dev_get_drvdata(dev); + struct ds1216_regs regs; + + ds1216_switch_ds_to_clock(priv->ioaddr); + ds1216_read(priv->ioaddr, (u8 *)®s); + + tm->tm_sec = bcd2bin(regs.sec); + tm->tm_min = bcd2bin(regs.min); + if (regs.hour & DS1216_HOUR_1224) { + /* AM/PM mode */ + tm->tm_hour = bcd2bin(regs.hour & 0x1f); + if (regs.hour & DS1216_HOUR_AMPM) + tm->tm_hour += 12; + } else + tm->tm_hour = bcd2bin(regs.hour & 0x3f); + tm->tm_wday = (regs.wday & 7) - 1; + tm->tm_mday = bcd2bin(regs.mday & 0x3f); + tm->tm_mon = bcd2bin(regs.month & 0x1f); + tm->tm_year = bcd2bin(regs.year); + if (tm->tm_year < 70) + tm->tm_year += 100; + + return 0; +} + +static int ds1216_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct ds1216_priv *priv = dev_get_drvdata(dev); + struct ds1216_regs regs; + + ds1216_switch_ds_to_clock(priv->ioaddr); + ds1216_read(priv->ioaddr, (u8 *)®s); + + regs.tsec = 0; /* clear 0.1 and 0.01 seconds */ + regs.sec = bin2bcd(tm->tm_sec); + regs.min = bin2bcd(tm->tm_min); + regs.hour &= DS1216_HOUR_1224; + if (regs.hour && tm->tm_hour > 12) { + regs.hour |= DS1216_HOUR_AMPM; + tm->tm_hour -= 12; + } + regs.hour |= bin2bcd(tm->tm_hour); + regs.wday &= ~7; + regs.wday |= tm->tm_wday; + regs.mday = bin2bcd(tm->tm_mday); + regs.month = bin2bcd(tm->tm_mon); + regs.year = bin2bcd(tm->tm_year % 100); + + ds1216_switch_ds_to_clock(priv->ioaddr); + ds1216_write(priv->ioaddr, (u8 *)®s); + return 0; +} + +static const struct rtc_class_ops ds1216_rtc_ops = { + .read_time = ds1216_rtc_read_time, + .set_time = ds1216_rtc_set_time, +}; + +static int __init ds1216_rtc_probe(struct platform_device *pdev) +{ + struct ds1216_priv *priv; + u8 dummy[8]; + + priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + platform_set_drvdata(pdev, priv); + + priv->ioaddr = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->ioaddr)) + return PTR_ERR(priv->ioaddr); + + priv->rtc = devm_rtc_device_register(&pdev->dev, "ds1216", + &ds1216_rtc_ops, THIS_MODULE); + if (IS_ERR(priv->rtc)) + return PTR_ERR(priv->rtc); + + /* dummy read to get clock into a known state */ + ds1216_read(priv->ioaddr, dummy); + return 0; +} + +static struct platform_driver ds1216_rtc_platform_driver = { + .driver = { + .name = "rtc-ds1216", + }, +}; + +module_platform_driver_probe(ds1216_rtc_platform_driver, ds1216_rtc_probe); + +MODULE_AUTHOR("Thomas Bogendoerfer <tsbogend@alpha.franken.de>"); +MODULE_DESCRIPTION("DS1216 RTC driver"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("platform:rtc-ds1216"); |
