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author | Linus Torvalds <torvalds@linux-foundation.org> | 2018-02-01 21:31:17 +0300 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2018-02-01 21:31:17 +0300 |
commit | f6cff79f1d122f78a4b35bf4b2f0112afcd89ea4 (patch) | |
tree | cf3a38576f9adbb3860982c25f72aebed2bb541a /drivers/misc/ds1682.c | |
parent | 47fcc0360cfb3fe82e4daddacad3c1cd80b0b75d (diff) | |
parent | 9ff6576e124b1227c27c1da43fe5f8ee908263e0 (diff) | |
download | linux-f6cff79f1d122f78a4b35bf4b2f0112afcd89ea4.tar.xz |
Merge tag 'char-misc-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc
Pull char/misc driver updates from Greg KH:
"Here is the big pull request for char/misc drivers for 4.16-rc1.
There's a lot of stuff in here. Three new driver subsystems were added
for various types of hardware busses:
- siox
- slimbus
- soundwire
as well as a new vboxguest subsystem for the VirtualBox hypervisor
drivers.
There's also big updates from the FPGA subsystem, lots of Android
binder fixes, the usual handful of hyper-v updates, and lots of other
smaller driver updates.
All of these have been in linux-next for a long time, with no reported
issues"
* tag 'char-misc-4.16-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc: (155 commits)
char: lp: use true or false for boolean values
android: binder: use VM_ALLOC to get vm area
android: binder: Use true and false for boolean values
lkdtm: fix handle_irq_event symbol for INT_HW_IRQ_EN
EISA: Delete error message for a failed memory allocation in eisa_probe()
EISA: Whitespace cleanup
misc: remove AVR32 dependencies
virt: vbox: Add error mapping for VERR_INVALID_NAME and VERR_NO_MORE_FILES
soundwire: Fix a signedness bug
uio_hv_generic: fix new type mismatch warnings
uio_hv_generic: fix type mismatch warnings
auxdisplay: img-ascii-lcd: add missing MODULE_DESCRIPTION/AUTHOR/LICENSE
uio_hv_generic: add rescind support
uio_hv_generic: check that host supports monitor page
uio_hv_generic: create send and receive buffers
uio: document uio_hv_generic regions
doc: fix documentation about uio_hv_generic
vmbus: add monitor_id and subchannel_id to sysfs per channel
vmbus: fix ABI documentation
uio_hv_generic: use ISR callback method
...
Diffstat (limited to 'drivers/misc/ds1682.c')
-rw-r--r-- | drivers/misc/ds1682.c | 35 |
1 files changed, 26 insertions, 9 deletions
diff --git a/drivers/misc/ds1682.c b/drivers/misc/ds1682.c index 7231260ac287..98a921ea9ee8 100644 --- a/drivers/misc/ds1682.c +++ b/drivers/misc/ds1682.c @@ -59,25 +59,42 @@ static ssize_t ds1682_show(struct device *dev, struct device_attribute *attr, { struct sensor_device_attribute_2 *sattr = to_sensor_dev_attr_2(attr); struct i2c_client *client = to_i2c_client(dev); - __le32 val = 0; + unsigned long long val, check; + __le32 val_le = 0; int rc; dev_dbg(dev, "ds1682_show() called on %s\n", attr->attr.name); /* Read the register */ rc = i2c_smbus_read_i2c_block_data(client, sattr->index, sattr->nr, - (u8 *) & val); + (u8 *)&val_le); if (rc < 0) return -EIO; - /* Special case: the 32 bit regs are time values with 1/4s - * resolution, scale them up to milliseconds */ - if (sattr->nr == 4) - return sprintf(buf, "%llu\n", - ((unsigned long long)le32_to_cpu(val)) * 250); + val = le32_to_cpu(val_le); + + if (sattr->index == DS1682_REG_ELAPSED) { + int retries = 5; + + /* Detect and retry when a tick occurs mid-read */ + do { + rc = i2c_smbus_read_i2c_block_data(client, sattr->index, + sattr->nr, + (u8 *)&val_le); + if (rc < 0 || retries <= 0) + return -EIO; + + check = val; + val = le32_to_cpu(val_le); + retries--; + } while (val != check && val != (check + 1)); + } - /* Format the output string and return # of bytes */ - return sprintf(buf, "%li\n", (long)le32_to_cpu(val)); + /* Format the output string and return # of bytes + * Special case: the 32 bit regs are time values with 1/4s + * resolution, scale them up to milliseconds + */ + return sprintf(buf, "%llu\n", (sattr->nr == 4) ? (val * 250) : val); } static ssize_t ds1682_store(struct device *dev, struct device_attribute *attr, |