From ed81cc612c92167fe7606773e036ee5ccef6c190 Mon Sep 17 00:00:00 2001 From: Jean Delvare Date: Tue, 21 Nov 2017 17:09:59 +0100 Subject: [PATCH 1/3] hwmon: Drop reference to Jean's tree This tree has not been used for over a year, Guenter is taking all the hwmon patches in practice. Signed-off-by: Jean Delvare Cc: Guenter Roeck Signed-off-by: Guenter Roeck --- MAINTAINERS | 1 - 1 file changed, 1 deletion(-) diff --git a/MAINTAINERS b/MAINTAINERS index aa71ab52fd76..533fbb03a95c 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -6174,7 +6174,6 @@ M: Jean Delvare M: Guenter Roeck L: linux-hwmon@vger.kernel.org W: http://hwmon.wiki.kernel.org/ -T: quilt http://jdelvare.nerim.net/devel/linux/jdelvare-hwmon/ T: git git://git.kernel.org/pub/scm/linux/kernel/git/groeck/linux-staging.git S: Maintained F: Documentation/hwmon/ From bd467e4eababe4c04272c1e646f066db02734c79 Mon Sep 17 00:00:00 2001 From: Robert Lippert Date: Mon, 27 Nov 2017 15:51:55 -0800 Subject: [PATCH 2/3] hwmon: (pmbus) Use 64bit math for DIRECT format values Power values in the 100s of watt range can easily blow past 32bit math limits when processing everything in microwatts. Use 64bit math instead to avoid these issues on common 32bit ARM BMC platforms. Fixes: 442aba78728e ("hwmon: PMBus device driver") Signed-off-by: Robert Lippert Signed-off-by: Guenter Roeck --- drivers/hwmon/pmbus/pmbus_core.c | 21 ++++++++++++--------- 1 file changed, 12 insertions(+), 9 deletions(-) diff --git a/drivers/hwmon/pmbus/pmbus_core.c b/drivers/hwmon/pmbus/pmbus_core.c index 52a58b8b6e1b..a139940cd991 100644 --- a/drivers/hwmon/pmbus/pmbus_core.c +++ b/drivers/hwmon/pmbus/pmbus_core.c @@ -21,6 +21,7 @@ #include #include +#include #include #include #include @@ -499,8 +500,8 @@ static long pmbus_reg2data_linear(struct pmbus_data *data, static long pmbus_reg2data_direct(struct pmbus_data *data, struct pmbus_sensor *sensor) { - long val = (s16) sensor->data; - long m, b, R; + s64 b, val = (s16)sensor->data; + s32 m, R; m = data->info->m[sensor->class]; b = data->info->b[sensor->class]; @@ -528,11 +529,12 @@ static long pmbus_reg2data_direct(struct pmbus_data *data, R--; } while (R < 0) { - val = DIV_ROUND_CLOSEST(val, 10); + val = div_s64(val + 5LL, 10L); /* round closest */ R++; } - return (val - b) / m; + val = div_s64(val - b, m); + return clamp_val(val, LONG_MIN, LONG_MAX); } /* @@ -656,7 +658,8 @@ static u16 pmbus_data2reg_linear(struct pmbus_data *data, static u16 pmbus_data2reg_direct(struct pmbus_data *data, struct pmbus_sensor *sensor, long val) { - long m, b, R; + s64 b, val64 = val; + s32 m, R; m = data->info->m[sensor->class]; b = data->info->b[sensor->class]; @@ -673,18 +676,18 @@ static u16 pmbus_data2reg_direct(struct pmbus_data *data, R -= 3; /* Adjust R and b for data in milli-units */ b *= 1000; } - val = val * m + b; + val64 = val64 * m + b; while (R > 0) { - val *= 10; + val64 *= 10; R--; } while (R < 0) { - val = DIV_ROUND_CLOSEST(val, 10); + val64 = div_s64(val64 + 5LL, 10L); /* round closest */ R++; } - return val; + return (u16)clamp_val(val64, S16_MIN, S16_MAX); } static u16 pmbus_data2reg_vid(struct pmbus_data *data, From 68615eb01f82256c19e41967bfb3eef902f77033 Mon Sep 17 00:00:00 2001 From: Peter Rosin Date: Mon, 27 Nov 2017 17:31:00 +0100 Subject: [PATCH 3/3] hwmon: (jc42) optionally try to disable the SMBUS timeout With a nxp,se97 chip on an atmel sama5d31 board, the I2C adapter driver is not always capable of avoiding the 25-35 ms timeout as specified by the SMBUS protocol. This may cause silent corruption of the last bit of any transfer, e.g. a one is read instead of a zero if the sensor chip times out. This also affects the eeprom half of the nxp-se97 chip, where this silent corruption was originally noticed. Other I2C adapters probably suffer similar issues, e.g. bit-banging comes to mind as risky... The SMBUS register in the nxp chip is not a standard Jedec register, but it is not special to the nxp chips either, at least the atmel chips have the same mechanism. Therefore, do not special case this on the manufacturer, it is opt-in via the device property anyway. Cc: stable@vger.kernel.org # 4.9+ Signed-off-by: Peter Rosin Acked-by: Rob Herring Signed-off-by: Guenter Roeck --- .../devicetree/bindings/hwmon/jc42.txt | 4 ++++ drivers/hwmon/jc42.c | 21 +++++++++++++++++++ 2 files changed, 25 insertions(+) diff --git a/Documentation/devicetree/bindings/hwmon/jc42.txt b/Documentation/devicetree/bindings/hwmon/jc42.txt index 07a250498fbb..f569db58f64a 100644 --- a/Documentation/devicetree/bindings/hwmon/jc42.txt +++ b/Documentation/devicetree/bindings/hwmon/jc42.txt @@ -34,6 +34,10 @@ Required properties: - reg: I2C address +Optional properties: +- smbus-timeout-disable: When set, the smbus timeout function will be disabled. + This is not supported on all chips. + Example: temp-sensor@1a { diff --git a/drivers/hwmon/jc42.c b/drivers/hwmon/jc42.c index 5f11dc014ed6..e5234f953a6d 100644 --- a/drivers/hwmon/jc42.c +++ b/drivers/hwmon/jc42.c @@ -22,6 +22,7 @@ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ +#include #include #include #include @@ -45,6 +46,7 @@ static const unsigned short normal_i2c[] = { #define JC42_REG_TEMP 0x05 #define JC42_REG_MANID 0x06 #define JC42_REG_DEVICEID 0x07 +#define JC42_REG_SMBUS 0x22 /* NXP and Atmel, possibly others? */ /* Status bits in temperature register */ #define JC42_ALARM_CRIT_BIT 15 @@ -75,6 +77,9 @@ static const unsigned short normal_i2c[] = { #define GT_MANID 0x1c68 /* Giantec */ #define GT_MANID2 0x132d /* Giantec, 2nd mfg ID */ +/* SMBUS register */ +#define SMBUS_STMOUT BIT(7) /* SMBus time-out, active low */ + /* Supported chips */ /* Analog Devices */ @@ -495,6 +500,22 @@ static int jc42_probe(struct i2c_client *client, const struct i2c_device_id *id) data->extended = !!(cap & JC42_CAP_RANGE); + if (device_property_read_bool(dev, "smbus-timeout-disable")) { + int smbus; + + /* + * Not all chips support this register, but from a + * quick read of various datasheets no chip appears + * incompatible with the below attempt to disable + * the timeout. And the whole thing is opt-in... + */ + smbus = i2c_smbus_read_word_swapped(client, JC42_REG_SMBUS); + if (smbus < 0) + return smbus; + i2c_smbus_write_word_swapped(client, JC42_REG_SMBUS, + smbus | SMBUS_STMOUT); + } + config = i2c_smbus_read_word_swapped(client, JC42_REG_CONFIG); if (config < 0) return config;