diff options
| author | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2026-08-23 13:28:57 -0700 |
| commit | 4352b8aee98005853aa63f57d6377282de17a33f (patch) | |
| tree | 27614d7a9ef05c32d089004e104364ce42324837 /drivers/rtc/rtc-msc313.c | |
| download | linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.tar.gz linux-stable-4352b8aee98005853aa63f57d6377282de17a33f.zip | |
Merge tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linuxgrafted
Pull I3C updates from Alexandre Belloni:
"A new driver this cycle, for the AMD AXI I3C controller.
There are also new features such as IBI wakeup support, SETAASA device
discovery and ACPI support for the the DAA methods, meaning we can now
communicate with the SPD devices on DDR5 modules.
New driver:
- AMD AXI I3C master controller
Subsystem:
- I3C Common Command Code (CCC) handling improvements, especially
around GET CCCs
- SETAASA device discovery support
- ACPI support for all existing DAA methods like SETDASA, SETNEWDA as
well as I2C devices on I3C bus
- IBI-based wakeup support
Drivers:
- dw: SETAASA support
- mipi-i3c-hci: advertise IBI wakeup capability, AMD_PT I3C
controller support, PIO queue management support for HCI v1.2
- renesas: improve suspend to RAM support, add runtime PM support"
* tag 'i3c/for-7.3' of git://git.kernel.org/pub/scm/linux/kernel/git/i3c/linux: (70 commits)
i3c: dw: reduce do_daa time if there's no client
i3c: mipi-i3c-hci: Add support for AMD_PT I3C controller
i3c: mipi-i3c-hci: Add PIO queue management support for HCI v1.2
i3c: mipi-i3c-hci: Fix missing STAT_IBI_STATUS_THLD in PIO mode
i3c: dw: rename "pclk" to "apb" to match dt-binding
i3c: dw: make struct dw_i3c_cmd smaller
i3c: dw: use COMMAND_PORT_TRANSFER_ARG instead of hardcoding
i3c: renesas: Don't register devices when ENTDAA times out
i3c: master: dw-i3c-master: fix OD timing for first broadcast
i3c: mipi-i3c-hci: Advertise IBI wakeup capability
i3c: mipi-i3c-hci: Factor out i3c_hci_sysdev()
i3c: mipi-i3c-hci-pci: Propagate I3C wakeup requirements to PCI
i3c: master: Reject IBI requests from non-IBI-capable devices
i3c: master: Add helper to query bus wakeup requirements
i3c: master: Report wakeup events for IBIs
i3c: master: Support IBI-based wakeup capability
i3c: master: Fix potential UAF in i3c_device_match()
i3c: master: Fix potential UAF in i3c_device_uevent()
i3c: Make dev->desc locking assumptions explicit
i3c: master: Fix use-after-free of master->this
...
Diffstat (limited to 'drivers/rtc/rtc-msc313.c')
| -rw-r--r-- | drivers/rtc/rtc-msc313.c | 248 |
1 files changed, 248 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-msc313.c b/drivers/rtc/rtc-msc313.c new file mode 100644 index 000000000..912a46c6f --- /dev/null +++ b/drivers/rtc/rtc-msc313.c @@ -0,0 +1,248 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Real time clocks driver for MStar/SigmaStar ARMv7 SoCs. + * Based on "Real Time Clock driver for msb252x." that was contained + * in various MStar kernels. + * + * (C) 2019 Daniel Palmer + * (C) 2021 Romain Perier + */ + +#include <linux/clk.h> +#include <linux/delay.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/platform_device.h> +#include <linux/rtc.h> + +/* Registers */ +#define REG_RTC_CTRL 0x00 +#define REG_RTC_FREQ_CW_L 0x04 +#define REG_RTC_FREQ_CW_H 0x08 +#define REG_RTC_LOAD_VAL_L 0x0C +#define REG_RTC_LOAD_VAL_H 0x10 +#define REG_RTC_MATCH_VAL_L 0x14 +#define REG_RTC_MATCH_VAL_H 0x18 +#define REG_RTC_STATUS_INT 0x1C +#define REG_RTC_CNT_VAL_L 0x20 +#define REG_RTC_CNT_VAL_H 0x24 + +/* Control bits for REG_RTC_CTRL */ +#define SOFT_RSTZ_BIT BIT(0) +#define CNT_EN_BIT BIT(1) +#define WRAP_EN_BIT BIT(2) +#define LOAD_EN_BIT BIT(3) +#define READ_EN_BIT BIT(4) +#define INT_MASK_BIT BIT(5) +#define INT_FORCE_BIT BIT(6) +#define INT_CLEAR_BIT BIT(7) + +/* Control bits for REG_RTC_STATUS_INT */ +#define RAW_INT_BIT BIT(0) +#define ALM_INT_BIT BIT(1) + +struct msc313_rtc { + struct rtc_device *rtc_dev; + void __iomem *rtc_base; +}; + +static int msc313_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm) +{ + struct msc313_rtc *priv = dev_get_drvdata(dev); + unsigned long seconds; + + seconds = readw(priv->rtc_base + REG_RTC_MATCH_VAL_L) + | ((unsigned long)readw(priv->rtc_base + REG_RTC_MATCH_VAL_H) << 16); + + rtc_time64_to_tm(seconds, &alarm->time); + + if (!(readw(priv->rtc_base + REG_RTC_CTRL) & INT_MASK_BIT)) + alarm->enabled = 1; + + return 0; +} + +static int msc313_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) +{ + struct msc313_rtc *priv = dev_get_drvdata(dev); + u16 reg; + + reg = readw(priv->rtc_base + REG_RTC_CTRL); + if (enabled) + reg &= ~INT_MASK_BIT; + else + reg |= INT_MASK_BIT; + writew(reg, priv->rtc_base + REG_RTC_CTRL); + return 0; +} + +static int msc313_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm) +{ + struct msc313_rtc *priv = dev_get_drvdata(dev); + unsigned long seconds; + + seconds = rtc_tm_to_time64(&alarm->time); + writew((seconds & 0xFFFF), priv->rtc_base + REG_RTC_MATCH_VAL_L); + writew((seconds >> 16) & 0xFFFF, priv->rtc_base + REG_RTC_MATCH_VAL_H); + + msc313_rtc_alarm_irq_enable(dev, alarm->enabled); + + return 0; +} + +static bool msc313_rtc_get_enabled(struct msc313_rtc *priv) +{ + return readw(priv->rtc_base + REG_RTC_CTRL) & CNT_EN_BIT; +} + +static void msc313_rtc_set_enabled(struct msc313_rtc *priv) +{ + u16 reg; + + reg = readw(priv->rtc_base + REG_RTC_CTRL); + reg |= CNT_EN_BIT; + writew(reg, priv->rtc_base + REG_RTC_CTRL); +} + +static int msc313_rtc_read_time(struct device *dev, struct rtc_time *tm) +{ + struct msc313_rtc *priv = dev_get_drvdata(dev); + u32 seconds; + u16 reg; + + if (!msc313_rtc_get_enabled(priv)) + return -EINVAL; + + reg = readw(priv->rtc_base + REG_RTC_CTRL); + writew(reg | READ_EN_BIT, priv->rtc_base + REG_RTC_CTRL); + + /* Wait for HW latch done */ + while (readw(priv->rtc_base + REG_RTC_CTRL) & READ_EN_BIT) + udelay(1); + + seconds = readw(priv->rtc_base + REG_RTC_CNT_VAL_L) + | ((unsigned long)readw(priv->rtc_base + REG_RTC_CNT_VAL_H) << 16); + + rtc_time64_to_tm(seconds, tm); + + return 0; +} + +static int msc313_rtc_set_time(struct device *dev, struct rtc_time *tm) +{ + struct msc313_rtc *priv = dev_get_drvdata(dev); + unsigned long seconds; + u16 reg; + + seconds = rtc_tm_to_time64(tm); + writew(seconds & 0xFFFF, priv->rtc_base + REG_RTC_LOAD_VAL_L); + writew((seconds >> 16) & 0xFFFF, priv->rtc_base + REG_RTC_LOAD_VAL_H); + + /* Enable load for loading value into internal RTC counter */ + reg = readw(priv->rtc_base + REG_RTC_CTRL); + writew(reg | LOAD_EN_BIT, priv->rtc_base + REG_RTC_CTRL); + + /* Wait for HW latch done */ + while (readw(priv->rtc_base + REG_RTC_CTRL) & LOAD_EN_BIT) + udelay(1); + msc313_rtc_set_enabled(priv); + return 0; +} + +static const struct rtc_class_ops msc313_rtc_ops = { + .read_time = msc313_rtc_read_time, + .set_time = msc313_rtc_set_time, + .read_alarm = msc313_rtc_read_alarm, + .set_alarm = msc313_rtc_set_alarm, + .alarm_irq_enable = msc313_rtc_alarm_irq_enable, +}; + +static irqreturn_t msc313_rtc_interrupt(s32 irq, void *dev_id) +{ + struct msc313_rtc *priv = dev_id; + u16 reg; + + reg = readw(priv->rtc_base + REG_RTC_STATUS_INT); + if (!(reg & ALM_INT_BIT)) + return IRQ_NONE; + + reg = readw(priv->rtc_base + REG_RTC_CTRL); + reg |= INT_CLEAR_BIT; + reg &= ~INT_FORCE_BIT; + writew(reg, priv->rtc_base + REG_RTC_CTRL); + + rtc_update_irq(priv->rtc_dev, 1, RTC_IRQF | RTC_AF); + + return IRQ_HANDLED; +} + +static int msc313_rtc_probe(struct platform_device *pdev) +{ + struct device *dev = &pdev->dev; + struct msc313_rtc *priv; + unsigned long rate; + struct clk *clk; + int ret; + int irq; + + priv = devm_kzalloc(&pdev->dev, sizeof(struct msc313_rtc), GFP_KERNEL); + if (!priv) + return -ENOMEM; + + priv->rtc_base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(priv->rtc_base)) + return PTR_ERR(priv->rtc_base); + + irq = platform_get_irq(pdev, 0); + if (irq < 0) + return -EINVAL; + + priv->rtc_dev = devm_rtc_allocate_device(dev); + if (IS_ERR(priv->rtc_dev)) + return PTR_ERR(priv->rtc_dev); + + priv->rtc_dev->ops = &msc313_rtc_ops; + priv->rtc_dev->range_max = U32_MAX; + + ret = devm_request_irq(dev, irq, msc313_rtc_interrupt, IRQF_SHARED, + dev_name(&pdev->dev), priv); + if (ret) { + dev_err(dev, "Could not request IRQ\n"); + return ret; + } + + clk = devm_clk_get_enabled(dev, NULL); + if (IS_ERR(clk)) { + dev_err(dev, "No input reference clock\n"); + return PTR_ERR(clk); + } + + rate = clk_get_rate(clk); + writew(rate & 0xFFFF, priv->rtc_base + REG_RTC_FREQ_CW_L); + writew((rate >> 16) & 0xFFFF, priv->rtc_base + REG_RTC_FREQ_CW_H); + + platform_set_drvdata(pdev, priv); + + return devm_rtc_register_device(priv->rtc_dev); +} + +static const struct of_device_id msc313_rtc_of_match_table[] = { + { .compatible = "mstar,msc313-rtc" }, + { } +}; +MODULE_DEVICE_TABLE(of, msc313_rtc_of_match_table); + +static struct platform_driver msc313_rtc_driver = { + .probe = msc313_rtc_probe, + .driver = { + .name = "msc313-rtc", + .of_match_table = msc313_rtc_of_match_table, + }, +}; + +module_platform_driver(msc313_rtc_driver); + +MODULE_AUTHOR("Daniel Palmer <daniel@thingy.jp>"); +MODULE_AUTHOR("Romain Perier <romain.perier@gmail.com>"); +MODULE_DESCRIPTION("MStar RTC Driver"); +MODULE_LICENSE("GPL v2"); |
