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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 10:05:51 +0000
commit5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch)
treea94efe259b9009378be6d90eb30d2b019d95c194 /drivers/rtc/rtc-tx4939.c
parentInitial commit. (diff)
downloadlinux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz
linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/rtc/rtc-tx4939.c')
-rw-r--r--drivers/rtc/rtc-tx4939.c304
1 files changed, 304 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-tx4939.c b/drivers/rtc/rtc-tx4939.c
new file mode 100644
index 000000000..715b82981
--- /dev/null
+++ b/drivers/rtc/rtc-tx4939.c
@@ -0,0 +1,304 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * TX4939 internal RTC driver
+ * Based on RBTX49xx patch from CELF patch archive.
+ *
+ * (C) Copyright TOSHIBA CORPORATION 2005-2007
+ */
+#include <linux/rtc.h>
+#include <linux/platform_device.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <linux/io.h>
+#include <linux/gfp.h>
+
+#define TX4939_RTCCTL_ALME 0x00000080
+#define TX4939_RTCCTL_ALMD 0x00000040
+#define TX4939_RTCCTL_BUSY 0x00000020
+
+#define TX4939_RTCCTL_COMMAND 0x00000007
+#define TX4939_RTCCTL_COMMAND_NOP 0x00000000
+#define TX4939_RTCCTL_COMMAND_GETTIME 0x00000001
+#define TX4939_RTCCTL_COMMAND_SETTIME 0x00000002
+#define TX4939_RTCCTL_COMMAND_GETALARM 0x00000003
+#define TX4939_RTCCTL_COMMAND_SETALARM 0x00000004
+
+#define TX4939_RTCTBC_PM 0x00000080
+#define TX4939_RTCTBC_COMP 0x0000007f
+
+#define TX4939_RTC_REG_RAMSIZE 0x00000100
+#define TX4939_RTC_REG_RWBSIZE 0x00000006
+
+struct tx4939_rtc_reg {
+ __u32 ctl;
+ __u32 adr;
+ __u32 dat;
+ __u32 tbc;
+};
+
+struct tx4939rtc_plat_data {
+ struct rtc_device *rtc;
+ struct tx4939_rtc_reg __iomem *rtcreg;
+ spinlock_t lock;
+};
+
+static int tx4939_rtc_cmd(struct tx4939_rtc_reg __iomem *rtcreg, int cmd)
+{
+ int i = 0;
+
+ __raw_writel(cmd, &rtcreg->ctl);
+ /* This might take 30us (next 32.768KHz clock) */
+ while (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_BUSY) {
+ /* timeout on approx. 100us (@ GBUS200MHz) */
+ if (i++ > 200 * 100)
+ return -EBUSY;
+ cpu_relax();
+ }
+ return 0;
+}
+
+static int tx4939_rtc_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct tx4939rtc_plat_data *pdata = dev_get_drvdata(dev);
+ struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg;
+ unsigned long secs = rtc_tm_to_time64(tm);
+ int i, ret;
+ unsigned char buf[6];
+
+ buf[0] = 0;
+ buf[1] = 0;
+ buf[2] = secs;
+ buf[3] = secs >> 8;
+ buf[4] = secs >> 16;
+ buf[5] = secs >> 24;
+ spin_lock_irq(&pdata->lock);
+ __raw_writel(0, &rtcreg->adr);
+ for (i = 0; i < 6; i++)
+ __raw_writel(buf[i], &rtcreg->dat);
+ ret = tx4939_rtc_cmd(rtcreg,
+ TX4939_RTCCTL_COMMAND_SETTIME |
+ (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALME));
+ spin_unlock_irq(&pdata->lock);
+ return ret;
+}
+
+static int tx4939_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct tx4939rtc_plat_data *pdata = dev_get_drvdata(dev);
+ struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg;
+ int i, ret;
+ unsigned long sec;
+ unsigned char buf[6];
+
+ spin_lock_irq(&pdata->lock);
+ ret = tx4939_rtc_cmd(rtcreg,
+ TX4939_RTCCTL_COMMAND_GETTIME |
+ (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALME));
+ if (ret) {
+ spin_unlock_irq(&pdata->lock);
+ return ret;
+ }
+ __raw_writel(2, &rtcreg->adr);
+ for (i = 2; i < 6; i++)
+ buf[i] = __raw_readl(&rtcreg->dat);
+ spin_unlock_irq(&pdata->lock);
+ sec = ((unsigned long)buf[5] << 24) | (buf[4] << 16) |
+ (buf[3] << 8) | buf[2];
+ rtc_time64_to_tm(sec, tm);
+ return 0;
+}
+
+static int tx4939_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct tx4939rtc_plat_data *pdata = dev_get_drvdata(dev);
+ struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg;
+ int i, ret;
+ unsigned long sec;
+ unsigned char buf[6];
+
+ sec = rtc_tm_to_time64(&alrm->time);
+ buf[0] = 0;
+ buf[1] = 0;
+ buf[2] = sec;
+ buf[3] = sec >> 8;
+ buf[4] = sec >> 16;
+ buf[5] = sec >> 24;
+ spin_lock_irq(&pdata->lock);
+ __raw_writel(0, &rtcreg->adr);
+ for (i = 0; i < 6; i++)
+ __raw_writel(buf[i], &rtcreg->dat);
+ ret = tx4939_rtc_cmd(rtcreg, TX4939_RTCCTL_COMMAND_SETALARM |
+ (alrm->enabled ? TX4939_RTCCTL_ALME : 0));
+ spin_unlock_irq(&pdata->lock);
+ return ret;
+}
+
+static int tx4939_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alrm)
+{
+ struct tx4939rtc_plat_data *pdata = dev_get_drvdata(dev);
+ struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg;
+ int i, ret;
+ unsigned long sec;
+ unsigned char buf[6];
+ u32 ctl;
+
+ spin_lock_irq(&pdata->lock);
+ ret = tx4939_rtc_cmd(rtcreg,
+ TX4939_RTCCTL_COMMAND_GETALARM |
+ (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALME));
+ if (ret) {
+ spin_unlock_irq(&pdata->lock);
+ return ret;
+ }
+ __raw_writel(2, &rtcreg->adr);
+ for (i = 2; i < 6; i++)
+ buf[i] = __raw_readl(&rtcreg->dat);
+ ctl = __raw_readl(&rtcreg->ctl);
+ alrm->enabled = (ctl & TX4939_RTCCTL_ALME) ? 1 : 0;
+ alrm->pending = (ctl & TX4939_RTCCTL_ALMD) ? 1 : 0;
+ spin_unlock_irq(&pdata->lock);
+ sec = ((unsigned long)buf[5] << 24) | (buf[4] << 16) |
+ (buf[3] << 8) | buf[2];
+ rtc_time64_to_tm(sec, &alrm->time);
+ return rtc_valid_tm(&alrm->time);
+}
+
+static int tx4939_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+ struct tx4939rtc_plat_data *pdata = dev_get_drvdata(dev);
+
+ spin_lock_irq(&pdata->lock);
+ tx4939_rtc_cmd(pdata->rtcreg,
+ TX4939_RTCCTL_COMMAND_NOP |
+ (enabled ? TX4939_RTCCTL_ALME : 0));
+ spin_unlock_irq(&pdata->lock);
+ return 0;
+}
+
+static irqreturn_t tx4939_rtc_interrupt(int irq, void *dev_id)
+{
+ struct tx4939rtc_plat_data *pdata = dev_get_drvdata(dev_id);
+ struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg;
+ unsigned long events = RTC_IRQF;
+
+ spin_lock(&pdata->lock);
+ if (__raw_readl(&rtcreg->ctl) & TX4939_RTCCTL_ALMD) {
+ events |= RTC_AF;
+ tx4939_rtc_cmd(rtcreg, TX4939_RTCCTL_COMMAND_NOP);
+ }
+ spin_unlock(&pdata->lock);
+ rtc_update_irq(pdata->rtc, 1, events);
+
+ return IRQ_HANDLED;
+}
+
+static const struct rtc_class_ops tx4939_rtc_ops = {
+ .read_time = tx4939_rtc_read_time,
+ .read_alarm = tx4939_rtc_read_alarm,
+ .set_alarm = tx4939_rtc_set_alarm,
+ .set_time = tx4939_rtc_set_time,
+ .alarm_irq_enable = tx4939_rtc_alarm_irq_enable,
+};
+
+static int tx4939_nvram_read(void *priv, unsigned int pos, void *val,
+ size_t bytes)
+{
+ struct tx4939rtc_plat_data *pdata = priv;
+ struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg;
+ u8 *buf = val;
+
+ spin_lock_irq(&pdata->lock);
+ for (; bytes; bytes--) {
+ __raw_writel(pos++, &rtcreg->adr);
+ *buf++ = __raw_readl(&rtcreg->dat);
+ }
+ spin_unlock_irq(&pdata->lock);
+ return 0;
+}
+
+static int tx4939_nvram_write(void *priv, unsigned int pos, void *val,
+ size_t bytes)
+{
+ struct tx4939rtc_plat_data *pdata = priv;
+ struct tx4939_rtc_reg __iomem *rtcreg = pdata->rtcreg;
+ u8 *buf = val;
+
+ spin_lock_irq(&pdata->lock);
+ for (; bytes; bytes--) {
+ __raw_writel(pos++, &rtcreg->adr);
+ __raw_writel(*buf++, &rtcreg->dat);
+ }
+ spin_unlock_irq(&pdata->lock);
+ return 0;
+}
+
+static int __init tx4939_rtc_probe(struct platform_device *pdev)
+{
+ struct rtc_device *rtc;
+ struct tx4939rtc_plat_data *pdata;
+ int irq, ret;
+ struct nvmem_config nvmem_cfg = {
+ .name = "tx4939_nvram",
+ .size = TX4939_RTC_REG_RAMSIZE,
+ .reg_read = tx4939_nvram_read,
+ .reg_write = tx4939_nvram_write,
+ };
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return -ENODEV;
+ pdata = devm_kzalloc(&pdev->dev, sizeof(*pdata), GFP_KERNEL);
+ if (!pdata)
+ return -ENOMEM;
+ platform_set_drvdata(pdev, pdata);
+
+ pdata->rtcreg = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(pdata->rtcreg))
+ return PTR_ERR(pdata->rtcreg);
+
+ spin_lock_init(&pdata->lock);
+ tx4939_rtc_cmd(pdata->rtcreg, TX4939_RTCCTL_COMMAND_NOP);
+ if (devm_request_irq(&pdev->dev, irq, tx4939_rtc_interrupt,
+ 0, pdev->name, &pdev->dev) < 0)
+ return -EBUSY;
+ rtc = devm_rtc_allocate_device(&pdev->dev);
+ if (IS_ERR(rtc))
+ return PTR_ERR(rtc);
+
+ rtc->ops = &tx4939_rtc_ops;
+ rtc->nvram_old_abi = true;
+ rtc->range_max = U32_MAX;
+
+ pdata->rtc = rtc;
+
+ nvmem_cfg.priv = pdata;
+ ret = rtc_nvmem_register(rtc, &nvmem_cfg);
+ if (ret)
+ return ret;
+
+ return rtc_register_device(rtc);
+}
+
+static int __exit tx4939_rtc_remove(struct platform_device *pdev)
+{
+ struct tx4939rtc_plat_data *pdata = platform_get_drvdata(pdev);
+
+ spin_lock_irq(&pdata->lock);
+ tx4939_rtc_cmd(pdata->rtcreg, TX4939_RTCCTL_COMMAND_NOP);
+ spin_unlock_irq(&pdata->lock);
+ return 0;
+}
+
+static struct platform_driver tx4939_rtc_driver = {
+ .remove = __exit_p(tx4939_rtc_remove),
+ .driver = {
+ .name = "tx4939rtc",
+ },
+};
+
+module_platform_driver_probe(tx4939_rtc_driver, tx4939_rtc_probe);
+
+MODULE_AUTHOR("Atsushi Nemoto <anemo@mba.ocn.ne.jp>");
+MODULE_DESCRIPTION("TX4939 internal RTC driver");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:tx4939rtc");