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authorDave Airlie <airlied@redhat.com>2015-04-20 11:32:26 +1000
committerDave Airlie <airlied@redhat.com>2015-04-20 13:05:20 +1000
commit2c33ce009ca2389dbf0535d0672214d09738e35e (patch)
tree6186a6458c3c160385d794a23eaf07c786a9e61b /drivers/rtc/rtc-digicolor.c
parentcec32a47010647e8b0603726ebb75b990a4057a4 (diff)
parent09d51602cf84a1264946711dd4ea0dddbac599a1 (diff)
Merge Linus master into drm-next
The merge is clean, but the arm build fails afterwards, due to API changes in the regulator tree. I've included the patch into the merge to fix the build. Signed-off-by: Dave Airlie <airlied@redhat.com>
Diffstat (limited to 'drivers/rtc/rtc-digicolor.c')
-rw-r--r--drivers/rtc/rtc-digicolor.c227
1 files changed, 227 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-digicolor.c b/drivers/rtc/rtc-digicolor.c
new file mode 100644
index 000000000000..8d05596a6765
--- /dev/null
+++ b/drivers/rtc/rtc-digicolor.c
@@ -0,0 +1,227 @@
+/*
+ * Real Time Clock driver for Conexant Digicolor
+ *
+ * Copyright (C) 2015 Paradox Innovation Ltd.
+ *
+ * Author: Baruch Siach <baruch@tkos.co.il>
+ *
+ * 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.
+ */
+
+#include <linux/io.h>
+#include <linux/iopoll.h>
+#include <linux/delay.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+#include <linux/of.h>
+
+#define DC_RTC_CONTROL 0x0
+#define DC_RTC_TIME 0x8
+#define DC_RTC_REFERENCE 0xc
+#define DC_RTC_ALARM 0x10
+#define DC_RTC_INTFLAG_CLEAR 0x14
+#define DC_RTC_INTENABLE 0x16
+
+#define DC_RTC_CMD_MASK 0xf
+#define DC_RTC_GO_BUSY BIT(7)
+
+#define CMD_NOP 0
+#define CMD_RESET 1
+#define CMD_WRITE 3
+#define CMD_READ 4
+
+#define CMD_DELAY_US (10*1000)
+#define CMD_TIMEOUT_US (500*CMD_DELAY_US)
+
+struct dc_rtc {
+ struct rtc_device *rtc_dev;
+ void __iomem *regs;
+};
+
+static int dc_rtc_cmds(struct dc_rtc *rtc, const u8 *cmds, int len)
+{
+ u8 val;
+ int i, ret;
+
+ for (i = 0; i < len; i++) {
+ writeb_relaxed((cmds[i] & DC_RTC_CMD_MASK) | DC_RTC_GO_BUSY,
+ rtc->regs + DC_RTC_CONTROL);
+ ret = readb_relaxed_poll_timeout(
+ rtc->regs + DC_RTC_CONTROL, val,
+ !(val & DC_RTC_GO_BUSY), CMD_DELAY_US, CMD_TIMEOUT_US);
+ if (ret < 0)
+ return ret;
+ }
+
+ return 0;
+}
+
+static int dc_rtc_read(struct dc_rtc *rtc, unsigned long *val)
+{
+ static const u8 read_cmds[] = {CMD_READ, CMD_NOP};
+ u32 reference, time1, time2;
+ int ret;
+
+ ret = dc_rtc_cmds(rtc, read_cmds, ARRAY_SIZE(read_cmds));
+ if (ret < 0)
+ return ret;
+
+ reference = readl_relaxed(rtc->regs + DC_RTC_REFERENCE);
+ time1 = readl_relaxed(rtc->regs + DC_RTC_TIME);
+ /* Read twice to ensure consistency */
+ while (1) {
+ time2 = readl_relaxed(rtc->regs + DC_RTC_TIME);
+ if (time1 == time2)
+ break;
+ time1 = time2;
+ }
+
+ *val = reference + time1;
+ return 0;
+}
+
+static int dc_rtc_write(struct dc_rtc *rtc, u32 val)
+{
+ static const u8 write_cmds[] = {CMD_WRITE, CMD_NOP, CMD_RESET, CMD_NOP};
+
+ writel_relaxed(val, rtc->regs + DC_RTC_REFERENCE);
+ return dc_rtc_cmds(rtc, write_cmds, ARRAY_SIZE(write_cmds));
+}
+
+static int dc_rtc_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct dc_rtc *rtc = dev_get_drvdata(dev);
+ unsigned long now;
+ int ret;
+
+ ret = dc_rtc_read(rtc, &now);
+ if (ret < 0)
+ return ret;
+ rtc_time64_to_tm(now, tm);
+
+ return 0;
+}
+
+static int dc_rtc_set_mmss(struct device *dev, unsigned long secs)
+{
+ struct dc_rtc *rtc = dev_get_drvdata(dev);
+
+ return dc_rtc_write(rtc, secs);
+}
+
+static int dc_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ struct dc_rtc *rtc = dev_get_drvdata(dev);
+ u32 alarm_reg, reference;
+ unsigned long now;
+ int ret;
+
+ alarm_reg = readl_relaxed(rtc->regs + DC_RTC_ALARM);
+ reference = readl_relaxed(rtc->regs + DC_RTC_REFERENCE);
+ rtc_time64_to_tm(reference + alarm_reg, &alarm->time);
+
+ ret = dc_rtc_read(rtc, &now);
+ if (ret < 0)
+ return ret;
+
+ alarm->pending = alarm_reg + reference > now;
+ alarm->enabled = readl_relaxed(rtc->regs + DC_RTC_INTENABLE);
+
+ return 0;
+}
+
+static int dc_rtc_set_alarm(struct device *dev, struct rtc_wkalrm *alarm)
+{
+ struct dc_rtc *rtc = dev_get_drvdata(dev);
+ time64_t alarm_time;
+ u32 reference;
+
+ alarm_time = rtc_tm_to_time64(&alarm->time);
+
+ reference = readl_relaxed(rtc->regs + DC_RTC_REFERENCE);
+ writel_relaxed(alarm_time - reference, rtc->regs + DC_RTC_ALARM);
+
+ writeb_relaxed(!!alarm->enabled, rtc->regs + DC_RTC_INTENABLE);
+
+ return 0;
+}
+
+static int dc_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled)
+{
+ struct dc_rtc *rtc = dev_get_drvdata(dev);
+
+ writeb_relaxed(!!enabled, rtc->regs + DC_RTC_INTENABLE);
+
+ return 0;
+}
+
+static struct rtc_class_ops dc_rtc_ops = {
+ .read_time = dc_rtc_read_time,
+ .set_mmss = dc_rtc_set_mmss,
+ .read_alarm = dc_rtc_read_alarm,
+ .set_alarm = dc_rtc_set_alarm,
+ .alarm_irq_enable = dc_rtc_alarm_irq_enable,
+};
+
+static irqreturn_t dc_rtc_irq(int irq, void *dev_id)
+{
+ struct dc_rtc *rtc = dev_id;
+
+ writeb_relaxed(1, rtc->regs + DC_RTC_INTFLAG_CLEAR);
+ rtc_update_irq(rtc->rtc_dev, 1, RTC_AF | RTC_IRQF);
+
+ return IRQ_HANDLED;
+}
+
+static int __init dc_rtc_probe(struct platform_device *pdev)
+{
+ struct resource *res;
+ struct dc_rtc *rtc;
+ int irq, ret;
+
+ rtc = devm_kzalloc(&pdev->dev, sizeof(*rtc), GFP_KERNEL);
+ if (!rtc)
+ return -ENOMEM;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ rtc->regs = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(rtc->regs))
+ return PTR_ERR(rtc->regs);
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0)
+ return irq;
+ ret = devm_request_irq(&pdev->dev, irq, dc_rtc_irq, 0, pdev->name, rtc);
+ if (ret < 0)
+ return ret;
+
+ platform_set_drvdata(pdev, rtc);
+ rtc->rtc_dev = devm_rtc_device_register(&pdev->dev, pdev->name,
+ &dc_rtc_ops, THIS_MODULE);
+ if (IS_ERR(rtc->rtc_dev))
+ return PTR_ERR(rtc->rtc_dev);
+
+ return 0;
+}
+
+static const struct of_device_id dc_dt_ids[] = {
+ { .compatible = "cnxt,cx92755-rtc" },
+ { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, dc_dt_ids);
+
+static struct platform_driver dc_rtc_driver = {
+ .driver = {
+ .name = "digicolor_rtc",
+ .of_match_table = of_match_ptr(dc_dt_ids),
+ },
+};
+module_platform_driver_probe(dc_rtc_driver, dc_rtc_probe);
+
+MODULE_AUTHOR("Baruch Siach <baruch@tkos.co.il>");
+MODULE_DESCRIPTION("Conexant Digicolor Realtime Clock Driver (RTC)");
+MODULE_LICENSE("GPL");