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| author | Kees Cook <kees+treewide@kernel.org> | 2026-09-02 15:31:14 -0700 |
|---|---|---|
| committer | Kees Cook <kees@kernel.org> | 2026-09-04 21:37:00 -0700 |
| commit | 3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d (patch) | |
| tree | c65086f9bdcd48c6360fb7cb4598bca084da1f32 /drivers/rtc/rtc-max6902.c | |
| download | linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.tar.gz linux-stable-3a2c4d55e32ad65efebdb6de44eef3bfa08bb49d.zip | |
treewide: refresh kmalloc_obj() conversionsgrafted
This is another run of the Coccinelle script for converting kmalloc()
family of allocations to kmalloc_obj() via the existing rules in
scripts/coccinelle/api/kmalloc_objs.cocci
This catches both the set of kmalloc() uses added since the first
kmalloc_obj() conversions in v7.0 and adds a large group missed in the
first pass due to Coccinelle not interacting well with the cleanup.h
scoped_...() family of macros[1]. I worked around this with spatch's
"--macro-file" argument to a file with all the scoped_...() macros mapped
to Coccinelle's YACFE_ITERATOR[2] as that was the closest viable control
flow indicator I could find.
Build tested allmodconfig on x86, arm64, arm, loongarch, mips, powerpc,
riscv, and s390 with no new warnings.
Link: https://lore.kernel.org/lkml/202609021314.8A9C0B8@keescook/ [1]
Link: https://github.com/coccinelle/coccinelle/blob/master/standard.h [2]
Signed-off-by: Kees Cook <kees+treewide@kernel.org>
Diffstat (limited to 'drivers/rtc/rtc-max6902.c')
| -rw-r--r-- | drivers/rtc/rtc-max6902.c | 154 |
1 files changed, 154 insertions, 0 deletions
diff --git a/drivers/rtc/rtc-max6902.c b/drivers/rtc/rtc-max6902.c new file mode 100644 index 000000000..daaeb6fb6 --- /dev/null +++ b/drivers/rtc/rtc-max6902.c @@ -0,0 +1,154 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* drivers/rtc/rtc-max6902.c + * + * Copyright (C) 2006 8D Technologies inc. + * Copyright (C) 2004 Compulab Ltd. + * + * Driver for MAX6902 spi RTC + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/platform_device.h> +#include <linux/init.h> +#include <linux/rtc.h> +#include <linux/spi/spi.h> +#include <linux/bcd.h> + +#define MAX6902_REG_SECONDS 0x01 +#define MAX6902_REG_MINUTES 0x03 +#define MAX6902_REG_HOURS 0x05 +#define MAX6902_REG_DATE 0x07 +#define MAX6902_REG_MONTH 0x09 +#define MAX6902_REG_DAY 0x0B +#define MAX6902_REG_YEAR 0x0D +#define MAX6902_REG_CONTROL 0x0F +#define MAX6902_REG_CENTURY 0x13 + +static int max6902_set_reg(struct device *dev, unsigned char address, + unsigned char data) +{ + struct spi_device *spi = to_spi_device(dev); + unsigned char buf[2]; + + /* MSB must be '0' to write */ + buf[0] = address & 0x7f; + buf[1] = data; + + return spi_write_then_read(spi, buf, 2, NULL, 0); +} + +static int max6902_get_reg(struct device *dev, unsigned char address, + unsigned char *data) +{ + struct spi_device *spi = to_spi_device(dev); + + /* Set MSB to indicate read */ + *data = address | 0x80; + + return spi_write_then_read(spi, data, 1, data, 1); +} + +static int max6902_read_time(struct device *dev, struct rtc_time *dt) +{ + int err, century; + struct spi_device *spi = to_spi_device(dev); + unsigned char buf[8]; + + buf[0] = 0xbf; /* Burst read */ + + err = spi_write_then_read(spi, buf, 1, buf, 8); + if (err != 0) + return err; + + /* The chip sends data in this order: + * Seconds, Minutes, Hours, Date, Month, Day, Year */ + dt->tm_sec = bcd2bin(buf[0]); + dt->tm_min = bcd2bin(buf[1]); + dt->tm_hour = bcd2bin(buf[2]); + dt->tm_mday = bcd2bin(buf[3]); + dt->tm_mon = bcd2bin(buf[4]) - 1; + dt->tm_wday = bcd2bin(buf[5]); + dt->tm_year = bcd2bin(buf[6]); + + /* Read century */ + err = max6902_get_reg(dev, MAX6902_REG_CENTURY, &buf[0]); + if (err != 0) + return err; + + century = bcd2bin(buf[0]) * 100; + + dt->tm_year += century; + dt->tm_year -= 1900; + + return 0; +} + +static int max6902_set_time(struct device *dev, struct rtc_time *dt) +{ + dt->tm_year = dt->tm_year + 1900; + + /* Remove write protection */ + max6902_set_reg(dev, MAX6902_REG_CONTROL, 0); + + max6902_set_reg(dev, MAX6902_REG_SECONDS, bin2bcd(dt->tm_sec)); + max6902_set_reg(dev, MAX6902_REG_MINUTES, bin2bcd(dt->tm_min)); + max6902_set_reg(dev, MAX6902_REG_HOURS, bin2bcd(dt->tm_hour)); + + max6902_set_reg(dev, MAX6902_REG_DATE, bin2bcd(dt->tm_mday)); + max6902_set_reg(dev, MAX6902_REG_MONTH, bin2bcd(dt->tm_mon + 1)); + max6902_set_reg(dev, MAX6902_REG_DAY, bin2bcd(dt->tm_wday)); + max6902_set_reg(dev, MAX6902_REG_YEAR, bin2bcd(dt->tm_year % 100)); + max6902_set_reg(dev, MAX6902_REG_CENTURY, bin2bcd(dt->tm_year / 100)); + + /* Compulab used a delay here. However, the datasheet + * does not mention a delay being required anywhere... */ + /* delay(2000); */ + + /* Write protect */ + max6902_set_reg(dev, MAX6902_REG_CONTROL, 0x80); + + return 0; +} + +static const struct rtc_class_ops max6902_rtc_ops = { + .read_time = max6902_read_time, + .set_time = max6902_set_time, +}; + +static int max6902_probe(struct spi_device *spi) +{ + struct rtc_device *rtc; + unsigned char tmp; + int res; + + spi->mode = SPI_MODE_3; + spi->bits_per_word = 8; + spi_setup(spi); + + res = max6902_get_reg(&spi->dev, MAX6902_REG_SECONDS, &tmp); + if (res != 0) + return res; + + rtc = devm_rtc_device_register(&spi->dev, "max6902", + &max6902_rtc_ops, THIS_MODULE); + if (IS_ERR(rtc)) + return PTR_ERR(rtc); + + spi_set_drvdata(spi, rtc); + return 0; +} + +static struct spi_driver max6902_driver = { + .driver = { + .name = "rtc-max6902", + }, + .probe = max6902_probe, +}; + +module_spi_driver(max6902_driver); + +MODULE_DESCRIPTION("max6902 spi RTC driver"); +MODULE_AUTHOR("Raphael Assenat"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS("spi:rtc-max6902"); |
