linux/drivers/w1, branch v5.8-rc3

w1: Replace zero-length array with flexible-array

2020-06-16T04:08:32Z

There is a regular need in the kernel to provide a way to declare having a dynamically sized set of trailing elements in a structure. Kernel code should always use “flexible array members”[1] for these cases. The older style of one-element or zero-length arrays should no longer be used[2]. [1] https://en.wikipedia.org/wiki/Flexible_array_member [2] https://github.com/KSPP/linux/issues/21 Signed-off-by: Gustavo A. R. Silva

treewide: replace '---help---' in Kconfig files with 'help'

2020-06-13T16:57:21Z

Since commit 84af7a6194e4 ("checkpatch: kconfig: prefer 'help' over '---help---'"), the number of '---help---' has been gradually decreasing, but there are still more than 2400 instances. This commit finishes the conversion. While I touched the lines, I also fixed the indentation. There are a variety of indentation styles found. a) 4 spaces + '---help---' b) 7 spaces + '---help---' c) 8 spaces + '---help---' d) 1 space + 1 tab + '---help---' e) 1 tab + '---help---' (correct indentation) f) 1 tab + 1 space + '---help---' g) 1 tab + 2 spaces + '---help---' In order to convert all of them to 1 tab + 'help', I ran the following commend: $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/' Signed-off-by: Masahiro Yamada

w1: omap-hdq: print dev_err if irq flags are not cleared

2020-05-27T10:18:49Z

If irq flags are not cleared for certain operations we print an error message. Since this should never occur in normal operation, this patch is an optional safety-net and debugging tool. Signed-off-by: H. Nikolaus Schaller Link: https://lore.kernel.org/r/2de305d3046c7281a7123347899abbaa64c54fb8.1590255176.git.hns@goldelico.com Signed-off-by: Greg Kroah-Hartman

w1: omap-hdq: fix interrupt handling which did show spurious timeouts

2020-05-27T10:18:49Z

Since commit 27d13da8782a ("w1: omap-hdq: Simplify driver with PM runtime autosuspend") was applied, I did see timeouts and wrong values when reading a bq27000 connected to hdq of the omap3. This occurred mainly after boot but remained and only sometimes settled down after several reads. root@letux:~# time cat /sys/class/power_supply/bq27000-battery/uevent POWER_SUPPLY_NAME=bq27000-battery POWER_SUPPLY_STATUS=Discharging POWER_SUPPLY_PRESENT=1 POWER_SUPPLY_VOLTAGE_NOW=0 POWER_SUPPLY_CURRENT_NOW=0 POWER_SUPPLY_CAPACITY=0 POWER_SUPPLY_CAPACITY_LEVEL=Normal POWER_SUPPLY_TEMP=-2731 POWER_SUPPLY_TIME_TO_EMPTY_NOW=0 POWER_SUPPLY_TIME_TO_EMPTY_AVG=0 POWER_SUPPLY_TIME_TO_FULL_NOW=0 POWER_SUPPLY_TECHNOLOGY=Li-ion POWER_SUPPLY_CHARGE_FULL=0 POWER_SUPPLY_CHARGE_NOW=0 POWER_SUPPLY_CHARGE_FULL_DESIGN=0 POWER_SUPPLY_CYCLE_COUNT=0 POWER_SUPPLY_ENERGY_NOW=0 POWER_SUPPLY_POWER_AVG=0 POWER_SUPPLY_HEALTH=Good POWER_SUPPLY_MANUFACTURER=Texas Instruments real 0m15.761s user 0m0.001s sys 0m0.025s root@letux:~# Sometimes the effect did disappear after accessing the device multiple times, speed went up and results became correct. All this indicates that some interrupts from the hdq controller are lost by the driver. Enabling debugging revealed that there were spurious tx and rx timeouts, i.e. the driver does not always recognise interrupts. The main problem is that rx and tx interrupts share a single variable which was sometimes reset to 0 wiping out other interrupts. And it was overwritten by a second interrupt, independent of whether the previous interrupt was already processed or not. This patch improves interrupt handling to avoid such races and loss of interrupt flags. The ideas are: * only the hdq_isr() sets bits in hdq_status * it does not reset any bits * it does wake_up() if any interrupt is pending * bits are only reset by the read/write/break functions if they were waited for * this makes sure that no interrupts can be lost * rx/tx/timeout bits are completely decoupled from each other (and not reset all after waiting for any of them) * which bits to reset is now specified by a new parameter to hdq_reset_irqstatus() * hdq_reset_irqstatus() also returns the state before resetting so that we can encapsulate the spinlock * this should now handle the case that the write and read are both already finished quickly before the hdq_write_byte() ends. * Or that two interrupts occur in succession before they are processed by the driver. Old code may have reset all status bits making the next hdq_read_byte() timeout. * the spinlock now always protects changing of bits in function hdq_reset_irqstatus() which could become a read-write-modify problem if the interrupt handler tries to read-modify-write exactly at the same moment * we add mutex protection also for hdq_write_byte() just to be safe to not to disturb a hdq_read_byte() triggered by some other thread/process. This patch was tested on a GTA04 and results in no boot problems any more. And first read after boot is now ok: root@letux:~# time cat /sys/class/power_supply/bq27000-battery/uevent POWER_SUPPLY_NAME=bq27000-battery POWER_SUPPLY_STATUS=Discharging POWER_SUPPLY_PRESENT=1 POWER_SUPPLY_VOLTAGE_NOW=3970000 POWER_SUPPLY_CURRENT_NOW=354144 POWER_SUPPLY_CAPACITY=82 POWER_SUPPLY_CAPACITY_LEVEL=Normal POWER_SUPPLY_TEMP=266 POWER_SUPPLY_TIME_TO_EMPTY_NOW=7680 POWER_SUPPLY_TIME_TO_EMPTY_AVG=7380 POWER_SUPPLY_TECHNOLOGY=Li-ion POWER_SUPPLY_CHARGE_FULL=934856 POWER_SUPPLY_CHARGE_NOW=763976 POWER_SUPPLY_CHARGE_FULL_DESIGN=1233792 POWER_SUPPLY_CYCLE_COUNT=82 POWER_SUPPLY_ENERGY_NOW=2852840 POWER_SUPPLY_POWER_AVG=1392840 POWER_SUPPLY_HEALTH=Good POWER_SUPPLY_MANUFACTURER=Texas Instruments real 0m0.233s user 0m0.000s sys 0m0.025s root@letux:~# It was also tested with dev_dbg enabled and more printk that all activities behave correctly, especially hdq_write_byte(), hdq_read_byte(), omap_hdq_break(). Not tested is omap_w1_triplet(). Fixes: 27d13da8782a ("w1: omap-hdq: Simplify driver with PM runtime autosuspend") Cc: stable@vger.kernel.org # v5.6+ Signed-off-by: H. Nikolaus Schaller Link: https://lore.kernel.org/r/68fc8623ae741878beef049273696d2377526165.1590255176.git.hns@goldelico.com Signed-off-by: Greg Kroah-Hartman

w1: omap-hdq: fix return value to be -1 if there is a timeout

2020-05-27T10:18:49Z

omap_w1_read_byte() should return -1 (or 0xff) in case of error (e.g. missing battery). The code accidentially overwrites the variable ret and not val, which is returned. So it will return the initial value 0 instead of -1. Fixes: 27d13da8782a ("w1: omap-hdq: Simplify driver with PM runtime autosuspend") Cc: stable@vger.kernel.org # v5.6+ Acked-by: Tony Lindgren Signed-off-by: H. Nikolaus Schaller Link: https://lore.kernel.org/r/b2c2192b461fbb9b8e9bea4ad514a49557a7210b.1590255176.git.hns@goldelico.com Signed-off-by: Greg Kroah-Hartman

w1: omap-hdq: cleanup to add missing newline for some dev_dbg

2020-05-27T10:18:48Z

Otherwise it will corrupt the console log during debugging. Fixes: 7b5362a603a1 ("w1: omap_hdq: Fix some error/debug handling.") Cc: stable@vger.kernel.org Acked-by: Tony Lindgren Signed-off-by: H. Nikolaus Schaller Link: https://lore.kernel.org/r/cd0d55749a091214106575f6e1d363c6db56622f.1590255176.git.hns@goldelico.com Signed-off-by: Greg Kroah-Hartman

w1_therm: remove redundant assignments to variable ret

2020-05-21T08:58:51Z

The variable ret is being initialized with a value that is never read and it is being updated later with a new value. The initialization is redundant and can be removed. Addresses-Coverity: ("Unused value") Signed-off-by: Colin Ian King Link: https://lore.kernel.org/r/20200519154553.873413-1-colin.king@canonical.com Signed-off-by: Greg Kroah-Hartman

w1_therm: Free the correct variable

2020-05-21T08:58:46Z

The problem is that we change "p_args" to point to the middle of the string so when we free it at the end of the function it's not freeing the same pointer that we originally allocated. Fixes: e2c94d6f5720 ("w1_therm: adding alarm sysfs entry") Signed-off-by: Dan Carpenter Link: https://lore.kernel.org/r/20200520120019.GA172354@mwanda Signed-off-by: Greg Kroah-Hartman

w1_therm: adding bulk read support to trigger multiple conversion on bus

2020-05-15T14:29:00Z

Adding bulk read support: Sending a 'trigger' command in the dedicated sysfs entry of bus master device send a conversion command for all the slaves on the bus. The sysfs entry is added as soon as at least one device supporting this feature is detected on the bus. The behavior of the sysfs reading temperature on the device is as follow: * If no bulk read pending, trigger a conversion on the device, wait for the conversion to be done, read the temperature in device RAM * If a bulk read has been trigger, access directly the device RAM This behavior is the same on the 2 sysfs entries ('temperature' and 'w1_slave'). Reading the therm_bulk_read sysfs give the status of bulk operations: * '-1': conversion in progress on at least 1 sensor * '1': conversion complete but at least one sensor has not been read yet * '0': no bulk operation. Reading temperature on ecah device will trigger a conversion As not all devices support bulk read feature, it has been added in device family structure. The attribute is set at master level as soon as a supporting device is discover. It is removed when the last supported device leave the bus. The count of supported device is kept with the static counter bulk_read_device_counter. A strong pull up is apply on the line if at least one device required it. The duration of the pull up is the max time required by a device on the line, which depends on the resolution settings of each device. The strong pull up could be adjust with the a module parameter. Updating documentation in Documentation/ABI/testing/sysfs-driver-w1_therm and Documentation/w1/slaves/w1_therm.rst accordingly. Signed-off-by: Akira Shimahara Link: https://lore.kernel.org/r/20200511203820.411483-1-akira215corp@gmail.com Signed-off-by: Greg Kroah-Hartman

w1_therm: adding alarm sysfs entry

2020-05-15T14:29:00Z

Adding device alarms settings by a dedicated sysfs entry alarms (RW): read or write TH and TL in the device RAM. Checking devices in alarm state could be performed using the master search command. As alarms temperature level are store in a 8 bit register on the device and are signed values, a safe cast shall be performed using the min and max temperature that device are able to measure. This is done by int_to_short inline function. A 'write_data' field is added in the device structure, to bind the correct writing function, as some devices may have 2 or 3 bytes RAM. Updating Documentation/ABI/testing/sysfs-driver-w1_therm accordingly. Signed-off-by: Akira Shimahara Link: https://lore.kernel.org/r/20200511203801.411253-1-akira215corp@gmail.com Signed-off-by: Greg Kroah-Hartman