diff options
| 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-macsmc.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-macsmc.c')
| -rw-r--r-- | drivers/rtc/rtc-macsmc.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-macsmc.c b/drivers/rtc/rtc-macsmc.c new file mode 100644 index 000000000..8fe883066 --- /dev/null +++ b/drivers/rtc/rtc-macsmc.c @@ -0,0 +1,140 @@ +// SPDX-License-Identifier: GPL-2.0-only OR MIT +/* + * Apple SMC RTC driver + * Copyright The Asahi Linux Contributors + */ + +#include <linux/bitops.h> +#include <linux/mfd/macsmc.h> +#include <linux/module.h> +#include <linux/nvmem-consumer.h> +#include <linux/of.h> +#include <linux/platform_device.h> +#include <linux/rtc.h> +#include <linux/slab.h> + +/* 48-bit RTC */ +#define RTC_BYTES 6 +#define RTC_BITS (8 * RTC_BYTES) + +/* 32768 Hz clock */ +#define RTC_SEC_SHIFT 15 + +struct macsmc_rtc { + struct device *dev; + struct apple_smc *smc; + struct rtc_device *rtc_dev; + struct nvmem_cell *rtc_offset; +}; + +static int macsmc_rtc_get_time(struct device *dev, struct rtc_time *tm) +{ + struct macsmc_rtc *rtc = dev_get_drvdata(dev); + u64 ctr = 0, off = 0; + time64_t now; + void *p_off; + size_t len; + int ret; + + ret = apple_smc_read(rtc->smc, SMC_KEY(CLKM), &ctr, RTC_BYTES); + if (ret < 0) + return ret; + if (ret != RTC_BYTES) + return -EIO; + + p_off = nvmem_cell_read(rtc->rtc_offset, &len); + if (IS_ERR(p_off)) + return PTR_ERR(p_off); + if (len < RTC_BYTES) { + kfree(p_off); + return -EIO; + } + + memcpy(&off, p_off, RTC_BYTES); + kfree(p_off); + + /* Sign extend from 48 to 64 bits, then arithmetic shift right 15 bits to get seconds */ + now = sign_extend64(ctr + off, RTC_BITS - 1) >> RTC_SEC_SHIFT; + rtc_time64_to_tm(now, tm); + + return ret; +} + +static int macsmc_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct macsmc_rtc *rtc = dev_get_drvdata(dev); + u64 ctr = 0, off = 0; + int ret; + + ret = apple_smc_read(rtc->smc, SMC_KEY(CLKM), &ctr, RTC_BYTES); + if (ret < 0) + return ret; + if (ret != RTC_BYTES) + return -EIO; + + /* This sets the offset such that the set second begins now */ + off = (rtc_tm_to_time64(tm) << RTC_SEC_SHIFT) - ctr; + return nvmem_cell_write(rtc->rtc_offset, &off, RTC_BYTES); +} + +static const struct rtc_class_ops macsmc_rtc_ops = { + .read_time = macsmc_rtc_get_time, + .set_time = macsmc_rtc_set_time, +}; + +static int macsmc_rtc_probe(struct platform_device *pdev) +{ + struct apple_smc *smc = dev_get_drvdata(pdev->dev.parent); + struct macsmc_rtc *rtc; + + /* + * MFD will probe this device even without a node in the device tree, + * thus bail out early if the SMC on the current machines does not + * support RTC and has no node in the device tree. + */ + if (!pdev->dev.of_node) + return -ENODEV; + + rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL); + if (!rtc) + return -ENOMEM; + + rtc->dev = &pdev->dev; + rtc->smc = smc; + + rtc->rtc_offset = devm_nvmem_cell_get(&pdev->dev, "rtc_offset"); + if (IS_ERR(rtc->rtc_offset)) + return dev_err_probe(&pdev->dev, PTR_ERR(rtc->rtc_offset), + "Failed to get rtc_offset NVMEM cell\n"); + + rtc->rtc_dev = devm_rtc_allocate_device(&pdev->dev); + if (IS_ERR(rtc->rtc_dev)) + return PTR_ERR(rtc->rtc_dev); + + rtc->rtc_dev->ops = &macsmc_rtc_ops; + rtc->rtc_dev->range_min = S64_MIN >> (RTC_SEC_SHIFT + (64 - RTC_BITS)); + rtc->rtc_dev->range_max = S64_MAX >> (RTC_SEC_SHIFT + (64 - RTC_BITS)); + + platform_set_drvdata(pdev, rtc); + + return devm_rtc_register_device(rtc->rtc_dev); +} + +static const struct of_device_id macsmc_rtc_of_table[] = { + { .compatible = "apple,smc-rtc", }, + {} +}; +MODULE_DEVICE_TABLE(of, macsmc_rtc_of_table); + +static struct platform_driver macsmc_rtc_driver = { + .driver = { + .name = "macsmc-rtc", + .of_match_table = macsmc_rtc_of_table, + }, + .probe = macsmc_rtc_probe, +}; +module_platform_driver(macsmc_rtc_driver); + +MODULE_LICENSE("Dual MIT/GPL"); +MODULE_DESCRIPTION("Apple SMC RTC driver"); +MODULE_AUTHOR("Hector Martin <marcan@marcan.st>"); |
