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authorJoel Fernandes <joelagnelf@nvidia.com>2026-07-18 13:15:36 -0400
committerPaul E. McKenney <paulmck@kernel.org>2026-07-23 10:39:57 -0700
commit34ff636f322c6d5e4f0a52338fa63a7dff09a495 (patch)
tree7629759c1ec7148b95bc8ab3080df20a5ecd2273 /drivers/rtc/rtc-m41t94.c
downloadlinux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.tar.gz
linux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.zip
scftorture: Count single_rpc offline failures in statistics outputgrafted
scf_torture_stats_print() aggregates each invoker thread's counters into a local scf_statistics structure before printing, but the n_single_rpc_ofl field is missing from the aggregation loop. As a result, the "single_rpc_ofl" value printed in the statistics line is always zero, even when smp_call_function_single() invocations for the RPC test have failed due to offline CPUs and been counted by the invoker threads. Add the missing accumulation so that the printed value reflects the actual counts. Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com> Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'drivers/rtc/rtc-m41t94.c')
-rw-r--r--drivers/rtc/rtc-m41t94.c145
1 files changed, 145 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-m41t94.c b/drivers/rtc/rtc-m41t94.c
new file mode 100644
index 000000000..6803b0273
--- /dev/null
+++ b/drivers/rtc/rtc-m41t94.c
@@ -0,0 +1,145 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Driver for ST M41T94 SPI RTC
+ *
+ * Copyright (C) 2008 Kim B. Heino
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/rtc.h>
+#include <linux/spi/spi.h>
+#include <linux/bcd.h>
+
+#define M41T94_REG_SECONDS 0x01
+#define M41T94_REG_MINUTES 0x02
+#define M41T94_REG_HOURS 0x03
+#define M41T94_REG_WDAY 0x04
+#define M41T94_REG_DAY 0x05
+#define M41T94_REG_MONTH 0x06
+#define M41T94_REG_YEAR 0x07
+#define M41T94_REG_HT 0x0c
+
+#define M41T94_BIT_HALT 0x40
+#define M41T94_BIT_STOP 0x80
+#define M41T94_BIT_CB 0x40
+#define M41T94_BIT_CEB 0x80
+
+static int m41t94_set_time(struct device *dev, struct rtc_time *tm)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ u8 buf[8]; /* write cmd + 7 registers */
+
+ dev_dbg(dev, "%s secs=%d, mins=%d, "
+ "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
+ "write", tm->tm_sec, tm->tm_min,
+ tm->tm_hour, tm->tm_mday,
+ tm->tm_mon, tm->tm_year, tm->tm_wday);
+
+ buf[0] = 0x80 | M41T94_REG_SECONDS; /* write time + date */
+ buf[M41T94_REG_SECONDS] = bin2bcd(tm->tm_sec);
+ buf[M41T94_REG_MINUTES] = bin2bcd(tm->tm_min);
+ buf[M41T94_REG_HOURS] = bin2bcd(tm->tm_hour);
+ buf[M41T94_REG_WDAY] = bin2bcd(tm->tm_wday + 1);
+ buf[M41T94_REG_DAY] = bin2bcd(tm->tm_mday);
+ buf[M41T94_REG_MONTH] = bin2bcd(tm->tm_mon + 1);
+
+ buf[M41T94_REG_HOURS] |= M41T94_BIT_CEB;
+ if (tm->tm_year >= 100)
+ buf[M41T94_REG_HOURS] |= M41T94_BIT_CB;
+ buf[M41T94_REG_YEAR] = bin2bcd(tm->tm_year % 100);
+
+ return spi_write(spi, buf, 8);
+}
+
+static int m41t94_read_time(struct device *dev, struct rtc_time *tm)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ u8 buf[2];
+ int ret, hour;
+
+ /* clear halt update bit */
+ ret = spi_w8r8(spi, M41T94_REG_HT);
+ if (ret < 0)
+ return ret;
+ if (ret & M41T94_BIT_HALT) {
+ buf[0] = 0x80 | M41T94_REG_HT;
+ buf[1] = ret & ~M41T94_BIT_HALT;
+ spi_write(spi, buf, 2);
+ }
+
+ /* clear stop bit */
+ ret = spi_w8r8(spi, M41T94_REG_SECONDS);
+ if (ret < 0)
+ return ret;
+ if (ret & M41T94_BIT_STOP) {
+ buf[0] = 0x80 | M41T94_REG_SECONDS;
+ buf[1] = ret & ~M41T94_BIT_STOP;
+ spi_write(spi, buf, 2);
+ }
+
+ tm->tm_sec = bcd2bin(spi_w8r8(spi, M41T94_REG_SECONDS));
+ tm->tm_min = bcd2bin(spi_w8r8(spi, M41T94_REG_MINUTES));
+ hour = spi_w8r8(spi, M41T94_REG_HOURS);
+ tm->tm_hour = bcd2bin(hour & 0x3f);
+ tm->tm_wday = bcd2bin(spi_w8r8(spi, M41T94_REG_WDAY)) - 1;
+ tm->tm_mday = bcd2bin(spi_w8r8(spi, M41T94_REG_DAY));
+ tm->tm_mon = bcd2bin(spi_w8r8(spi, M41T94_REG_MONTH)) - 1;
+ tm->tm_year = bcd2bin(spi_w8r8(spi, M41T94_REG_YEAR));
+ if ((hour & M41T94_BIT_CB) || !(hour & M41T94_BIT_CEB))
+ tm->tm_year += 100;
+
+ dev_dbg(dev, "%s secs=%d, mins=%d, "
+ "hours=%d, mday=%d, mon=%d, year=%d, wday=%d\n",
+ "read", tm->tm_sec, tm->tm_min,
+ tm->tm_hour, tm->tm_mday,
+ tm->tm_mon, tm->tm_year, tm->tm_wday);
+
+ return 0;
+}
+
+static const struct rtc_class_ops m41t94_rtc_ops = {
+ .read_time = m41t94_read_time,
+ .set_time = m41t94_set_time,
+};
+
+static struct spi_driver m41t94_driver;
+
+static int m41t94_probe(struct spi_device *spi)
+{
+ struct rtc_device *rtc;
+ int res;
+
+ spi->bits_per_word = 8;
+ spi_setup(spi);
+
+ res = spi_w8r8(spi, M41T94_REG_SECONDS);
+ if (res < 0) {
+ dev_err(&spi->dev, "not found.\n");
+ return res;
+ }
+
+ rtc = devm_rtc_device_register(&spi->dev, m41t94_driver.driver.name,
+ &m41t94_rtc_ops, THIS_MODULE);
+ if (IS_ERR(rtc))
+ return PTR_ERR(rtc);
+
+ spi_set_drvdata(spi, rtc);
+
+ return 0;
+}
+
+static struct spi_driver m41t94_driver = {
+ .driver = {
+ .name = "rtc-m41t94",
+ },
+ .probe = m41t94_probe,
+};
+
+module_spi_driver(m41t94_driver);
+
+MODULE_AUTHOR("Kim B. Heino <Kim.Heino@bluegiga.com>");
+MODULE_DESCRIPTION("Driver for ST M41T94 SPI RTC");
+MODULE_LICENSE("GPL");
+MODULE_ALIAS("spi:rtc-m41t94");