diff options
Diffstat (limited to 'drivers/rtc/rtc-rs5c372.c')
| -rw-r--r-- | drivers/rtc/rtc-rs5c372.c | 311 |
1 files changed, 261 insertions, 50 deletions
diff --git a/drivers/rtc/rtc-rs5c372.c b/drivers/rtc/rtc-rs5c372.c index d4eff8d7131f..f8fab0205f8c 100644 --- a/drivers/rtc/rtc-rs5c372.c +++ b/drivers/rtc/rtc-rs5c372.c @@ -1,13 +1,10 @@ +// SPDX-License-Identifier: GPL-2.0-only /* * An I2C driver for Ricoh RS5C372, R2025S/D and RV5C38[67] RTCs * * Copyright (C) 2005 Pavel Mironchik <pmironchik@optifacio.net> * Copyright (C) 2006 Tower Technologies * Copyright (C) 2008 Paul Mundt - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License version 2 as - * published by the Free Software Foundation. */ #include <linux/i2c.h> @@ -15,7 +12,7 @@ #include <linux/bcd.h> #include <linux/slab.h> #include <linux/module.h> -#include <linux/of_device.h> +#include <linux/of.h> /* * Ricoh has a family of I2C based RTCs, which differ only slightly from @@ -31,8 +28,10 @@ #define RS5C372_REG_MONTH 5 #define RS5C372_REG_YEAR 6 #define RS5C372_REG_TRIM 7 -# define RS5C372_TRIM_XSL 0x80 +# define RS5C372_TRIM_XSL 0x80 /* only if RS5C372[a|b] */ # define RS5C372_TRIM_MASK 0x7F +# define R2221TL_TRIM_DEV (1 << 7) /* only if R2221TL */ +# define RS5C372_TRIM_DECR (1 << 6) #define RS5C_REG_ALARM_A_MIN 8 /* or ALARM_W */ #define RS5C_REG_ALARM_A_HOURS 9 @@ -52,8 +51,10 @@ # define RS5C_CTRL1_CT4 (4 << 0) /* 1 Hz level irq */ #define RS5C_REG_CTRL2 15 # define RS5C372_CTRL2_24 (1 << 5) -# define R2025_CTRL2_XST (1 << 5) -# define RS5C_CTRL2_XSTP (1 << 4) /* only if !R2025S/D */ +# define RS5C_CTRL2_XSTP (1 << 4) /* only if !R2x2x */ +# define R2x2x_CTRL2_VDET (1 << 6) /* only if R2x2x */ +# define R2x2x_CTRL2_XSTP (1 << 5) /* only if R2x2x */ +# define R2x2x_CTRL2_PON (1 << 4) /* only if R2x2x */ # define RS5C_CTRL2_CTFG (1 << 2) # define RS5C_CTRL2_AAFG (1 << 1) /* or WAFG */ # define RS5C_CTRL2_BAFG (1 << 0) /* or DAFG */ @@ -84,7 +85,7 @@ static const struct i2c_device_id rs5c372_id[] = { }; MODULE_DEVICE_TABLE(i2c, rs5c372_id); -static const struct of_device_id rs5c372_of_match[] = { +static const __maybe_unused struct of_device_id rs5c372_of_match[] = { { .compatible = "ricoh,r2025sd", .data = (void *)rtc_r2025sd @@ -149,7 +150,7 @@ static int rs5c_get_regs(struct rs5c372 *rs5c) * least 80219 chips; this works around that bug. * * The third method on the other hand doesn't work for the SMBus-only - * configurations, so we use the the first method there, stripping off + * configurations, so we use the first method there, stripping off * the extra register in the process. */ if (rs5c->smbus) { @@ -207,14 +208,32 @@ static unsigned rs5c_hr2reg(struct rs5c372 *rs5c, unsigned hour) return bin2bcd(hour); } -static int rs5c372_get_datetime(struct i2c_client *client, struct rtc_time *tm) +static int rs5c372_rtc_read_time(struct device *dev, struct rtc_time *tm) { + struct i2c_client *client = to_i2c_client(dev); struct rs5c372 *rs5c = i2c_get_clientdata(client); int status = rs5c_get_regs(rs5c); + unsigned char ctrl2 = rs5c->regs[RS5C_REG_CTRL2]; if (status < 0) return status; + switch (rs5c->type) { + case rtc_r2025sd: + case rtc_r2221tl: + if ((rs5c->type == rtc_r2025sd && !(ctrl2 & R2x2x_CTRL2_XSTP)) || + (rs5c->type == rtc_r2221tl && (ctrl2 & R2x2x_CTRL2_XSTP))) { + dev_warn(&client->dev, "rtc oscillator interruption detected. Please reset the rtc clock.\n"); + return -EINVAL; + } + break; + default: + if (ctrl2 & RS5C_CTRL2_XSTP) { + dev_warn(&client->dev, "rtc oscillator interruption detected. Please reset the rtc clock.\n"); + return -EINVAL; + } + } + tm->tm_sec = bcd2bin(rs5c->regs[RS5C372_REG_SECS] & 0x7f); tm->tm_min = bcd2bin(rs5c->regs[RS5C372_REG_MINS] & 0x7f); tm->tm_hour = rs5c_reg2hr(rs5c, rs5c->regs[RS5C372_REG_HOURS]); @@ -234,14 +253,15 @@ static int rs5c372_get_datetime(struct i2c_client *client, struct rtc_time *tm) tm->tm_sec, tm->tm_min, tm->tm_hour, tm->tm_mday, tm->tm_mon, tm->tm_year, tm->tm_wday); - /* rtc might need initialization */ - return rtc_valid_tm(tm); + return 0; } -static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm) +static int rs5c372_rtc_set_time(struct device *dev, struct rtc_time *tm) { + struct i2c_client *client = to_i2c_client(dev); struct rs5c372 *rs5c = i2c_get_clientdata(client); unsigned char buf[7]; + unsigned char ctrl2; int addr; dev_dbg(&client->dev, "%s: tm is secs=%d, mins=%d, hours=%d " @@ -260,7 +280,32 @@ static int rs5c372_set_datetime(struct i2c_client *client, struct rtc_time *tm) buf[6] = bin2bcd(tm->tm_year - 100); if (i2c_smbus_write_i2c_block_data(client, addr, sizeof(buf), buf) < 0) { - dev_err(&client->dev, "%s: write error\n", __func__); + dev_dbg(&client->dev, "%s: write error in line %i\n", + __func__, __LINE__); + return -EIO; + } + + addr = RS5C_ADDR(RS5C_REG_CTRL2); + ctrl2 = i2c_smbus_read_byte_data(client, addr); + + /* clear rtc warning bits */ + switch (rs5c->type) { + case rtc_r2025sd: + case rtc_r2221tl: + ctrl2 &= ~(R2x2x_CTRL2_VDET | R2x2x_CTRL2_PON); + if (rs5c->type == rtc_r2025sd) + ctrl2 |= R2x2x_CTRL2_XSTP; + else + ctrl2 &= ~R2x2x_CTRL2_XSTP; + break; + default: + ctrl2 &= ~RS5C_CTRL2_XSTP; + break; + } + + if (i2c_smbus_write_byte_data(client, addr, ctrl2) < 0) { + dev_dbg(&client->dev, "%s: write error in line %i\n", + __func__, __LINE__); return -EIO; } @@ -281,8 +326,12 @@ static int rs5c372_get_trim(struct i2c_client *client, int *osc, int *trim) struct rs5c372 *rs5c372 = i2c_get_clientdata(client); u8 tmp = rs5c372->regs[RS5C372_REG_TRIM]; - if (osc) - *osc = (tmp & RS5C372_TRIM_XSL) ? 32000 : 32768; + if (osc) { + if (rs5c372->type == rtc_rs5c372a || rs5c372->type == rtc_rs5c372b) + *osc = (tmp & RS5C372_TRIM_XSL) ? 32000 : 32768; + else + *osc = 32768; + } if (trim) { dev_dbg(&client->dev, "%s: raw trim=%x\n", __func__, tmp); @@ -305,17 +354,6 @@ static int rs5c372_get_trim(struct i2c_client *client, int *osc, int *trim) } #endif -static int rs5c372_rtc_read_time(struct device *dev, struct rtc_time *tm) -{ - return rs5c372_get_datetime(to_i2c_client(dev), tm); -} - -static int rs5c372_rtc_set_time(struct device *dev, struct rtc_time *tm) -{ - return rs5c372_set_datetime(to_i2c_client(dev), tm); -} - - static int rs5c_rtc_alarm_irq_enable(struct device *dev, unsigned int enabled) { struct i2c_client *client = to_i2c_client(dev); @@ -453,6 +491,176 @@ static int rs5c372_rtc_proc(struct device *dev, struct seq_file *seq) #define rs5c372_rtc_proc NULL #endif +#ifdef CONFIG_RTC_INTF_DEV +static int rs5c372_ioctl(struct device *dev, unsigned int cmd, unsigned long arg) +{ + struct rs5c372 *rs5c = i2c_get_clientdata(to_i2c_client(dev)); + unsigned char ctrl2; + int addr; + unsigned int flags; + + dev_dbg(dev, "%s: cmd=%x\n", __func__, cmd); + + addr = RS5C_ADDR(RS5C_REG_CTRL2); + ctrl2 = i2c_smbus_read_byte_data(rs5c->client, addr); + + switch (cmd) { + case RTC_VL_READ: + flags = 0; + + switch (rs5c->type) { + case rtc_r2025sd: + case rtc_r2221tl: + if ((rs5c->type == rtc_r2025sd && !(ctrl2 & R2x2x_CTRL2_XSTP)) || + (rs5c->type == rtc_r2221tl && (ctrl2 & R2x2x_CTRL2_XSTP))) { + flags |= RTC_VL_DATA_INVALID; + } + if (ctrl2 & R2x2x_CTRL2_VDET) + flags |= RTC_VL_BACKUP_LOW; + break; + default: + if (ctrl2 & RS5C_CTRL2_XSTP) + flags |= RTC_VL_DATA_INVALID; + break; + } + + return put_user(flags, (unsigned int __user *)arg); + case RTC_VL_CLR: + /* clear VDET bit */ + if (rs5c->type == rtc_r2025sd || rs5c->type == rtc_r2221tl) { + ctrl2 &= ~R2x2x_CTRL2_VDET; + if (i2c_smbus_write_byte_data(rs5c->client, addr, ctrl2) < 0) { + dev_dbg(&rs5c->client->dev, "%s: write error in line %i\n", + __func__, __LINE__); + return -EIO; + } + } + return 0; + default: + return -ENOIOCTLCMD; + } + return 0; +} +#else +#define rs5c372_ioctl NULL +#endif + +static int rs5c372_read_offset(struct device *dev, long *offset) +{ + struct rs5c372 *rs5c = i2c_get_clientdata(to_i2c_client(dev)); + u8 val = rs5c->regs[RS5C372_REG_TRIM]; + long ppb_per_step = 0; + bool decr = val & RS5C372_TRIM_DECR; + + switch (rs5c->type) { + case rtc_r2221tl: + ppb_per_step = val & R2221TL_TRIM_DEV ? 1017 : 3051; + break; + case rtc_rs5c372a: + case rtc_rs5c372b: + ppb_per_step = val & RS5C372_TRIM_XSL ? 3125 : 3051; + break; + default: + ppb_per_step = 3051; + break; + } + + /* Only bits[0:5] repsents the time counts */ + val &= 0x3F; + + /* If bits[1:5] are all 0, it means no increment or decrement */ + if (!(val & 0x3E)) { + *offset = 0; + } else { + if (decr) + *offset = -(((~val) & 0x3F) + 1) * ppb_per_step; + else + *offset = (val - 1) * ppb_per_step; + } + + return 0; +} + +static int rs5c372_set_offset(struct device *dev, long offset) +{ + struct rs5c372 *rs5c = i2c_get_clientdata(to_i2c_client(dev)); + int addr = RS5C_ADDR(RS5C372_REG_TRIM); + u8 val = 0; + u8 tmp = 0; + long ppb_per_step = 3051; + long steps = LONG_MIN; + + switch (rs5c->type) { + case rtc_rs5c372a: + case rtc_rs5c372b: + tmp = rs5c->regs[RS5C372_REG_TRIM]; + if (tmp & RS5C372_TRIM_XSL) { + ppb_per_step = 3125; + val |= RS5C372_TRIM_XSL; + } + break; + case rtc_r2221tl: + /* + * Check if it is possible to use high resolution mode (DEV=1). + * In this mode, the minimum resolution is 2 / (32768 * 20 * 3), + * which is about 1017 ppb. + */ + steps = DIV_ROUND_CLOSEST(offset, 1017); + if (steps >= -0x3E && steps <= 0x3E) { + ppb_per_step = 1017; + val |= R2221TL_TRIM_DEV; + } else { + /* + * offset is out of the range of high resolution mode. + * Try to use low resolution mode (DEV=0). In this mode, + * the minimum resolution is 2 / (32768 * 20), which is + * about 3051 ppb. + */ + steps = LONG_MIN; + } + break; + default: + break; + } + + if (steps == LONG_MIN) { + steps = DIV_ROUND_CLOSEST(offset, ppb_per_step); + if (steps > 0x3E || steps < -0x3E) + return -ERANGE; + } + + if (steps > 0) { + val |= steps + 1; + } else { + val |= RS5C372_TRIM_DECR; + val |= (~(-steps - 1)) & 0x3F; + } + + if (!steps || !(val & 0x3E)) { + /* + * if offset is too small, set oscillation adjustment register + * or time trimming register with its default value whic means + * no increment or decrement. But for rs5c372[a|b], the XSL bit + * should be kept unchanged. + */ + if (rs5c->type == rtc_rs5c372a || rs5c->type == rtc_rs5c372b) + val &= RS5C372_TRIM_XSL; + else + val = 0; + } + + dev_dbg(&rs5c->client->dev, "write 0x%x for offset %ld\n", val, offset); + + if (i2c_smbus_write_byte_data(rs5c->client, addr, val) < 0) { + dev_err(&rs5c->client->dev, "failed to write 0x%x to reg %d\n", val, addr); + return -EIO; + } + + rs5c->regs[RS5C372_REG_TRIM] = val; + + return 0; +} + static const struct rtc_class_ops rs5c372_rtc_ops = { .proc = rs5c372_rtc_proc, .read_time = rs5c372_rtc_read_time, @@ -460,6 +668,9 @@ static const struct rtc_class_ops rs5c372_rtc_ops = { .read_alarm = rs5c_read_alarm, .set_alarm = rs5c_set_alarm, .alarm_irq_enable = rs5c_rtc_alarm_irq_enable, + .ioctl = rs5c372_ioctl, + .read_offset = rs5c372_read_offset, + .set_offset = rs5c372_set_offset, }; #if IS_ENABLED(CONFIG_RTC_INTF_SYSFS) @@ -529,20 +740,25 @@ static int rs5c_oscillator_setup(struct rs5c372 *rs5c372) unsigned char buf[2]; int addr, i, ret = 0; - if (rs5c372->type == rtc_r2025sd) { - if (rs5c372->regs[RS5C_REG_CTRL2] & R2025_CTRL2_XST) - return ret; - rs5c372->regs[RS5C_REG_CTRL2] |= R2025_CTRL2_XST; - } else { - if (!(rs5c372->regs[RS5C_REG_CTRL2] & RS5C_CTRL2_XSTP)) - return ret; - rs5c372->regs[RS5C_REG_CTRL2] &= ~RS5C_CTRL2_XSTP; - } - addr = RS5C_ADDR(RS5C_REG_CTRL1); buf[0] = rs5c372->regs[RS5C_REG_CTRL1]; buf[1] = rs5c372->regs[RS5C_REG_CTRL2]; + switch (rs5c372->type) { + case rtc_r2025sd: + if (buf[1] & R2x2x_CTRL2_XSTP) + return ret; + break; + case rtc_r2221tl: + if (!(buf[1] & R2x2x_CTRL2_XSTP)) + return ret; + break; + default: + if (!(buf[1] & RS5C_CTRL2_XSTP)) + return ret; + break; + } + /* use 24hr mode */ switch (rs5c372->type) { case rtc_rs5c372a: @@ -575,13 +791,11 @@ static int rs5c_oscillator_setup(struct rs5c372 *rs5c372) return 0; } -static int rs5c372_probe(struct i2c_client *client, - const struct i2c_device_id *id) +static int rs5c372_probe(struct i2c_client *client) { int err = 0; int smbus_mode = 0; struct rs5c372 *rs5c372; - struct rtc_time tm; dev_dbg(&client->dev, "%s\n", __func__); @@ -611,11 +825,12 @@ static int rs5c372_probe(struct i2c_client *client, rs5c372->client = client; i2c_set_clientdata(client, rs5c372); - if (client->dev.of_node) - rs5c372->type = (enum rtc_type) - of_device_get_match_data(&client->dev); - else + if (client->dev.of_node) { + rs5c372->type = (uintptr_t)of_device_get_match_data(&client->dev); + } else { + const struct i2c_device_id *id = i2c_match_id(rs5c372_id, client); rs5c372->type = id->driver_data; + } /* we read registers 0x0f then 0x00-0x0f; skip the first one */ rs5c372->regs = &rs5c372->buf[1]; @@ -662,9 +877,6 @@ static int rs5c372_probe(struct i2c_client *client, goto exit; } - if (rs5c372_get_datetime(client, &tm) < 0) - dev_warn(&client->dev, "clock needs to be set\n"); - dev_info(&client->dev, "%s found, %s\n", ({ char *s; switch (rs5c372->type) { case rtc_r2025sd: s = "r2025sd"; break; @@ -698,10 +910,9 @@ exit: return err; } -static int rs5c372_remove(struct i2c_client *client) +static void rs5c372_remove(struct i2c_client *client) { rs5c_sysfs_unregister(&client->dev); - return 0; } static struct i2c_driver rs5c372_driver = { |