Re: [PATCH 2/4] rtc: abx80x: Enable SQW output

From: Kirill Kapranov
Date: Tue Mar 30 2021 - 11:29:32 EST


Hi Dan,

Thank you very much for pointing out the issues.
However, I'm not sure that the code, you have analyzed, will be a part of final patch set. I intend to redesign all the code deeply, as Alexandre Belloni suggested [1].

Thank you again!

--
Best Regards,
Kirill Kapranov
Software Engineer
CompuLab Ltd.
[1] https://marc.info/?l=linux-rtc&m=161696606727215&w=2

On 3/29/21 9:19 AM, Dan Carpenter wrote:
Hi Kirill,

url: https://github.com/0day-ci/linux/commits/Kirill-Kapranov/rtc-abx80x-Enable-distributed-digital-calibration/20210329-053233
base: https://git.kernel.org/pub/scm/linux/kernel/git/abelloni/linux.git rtc-next
config: i386-randconfig-m021-20210328 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Reported-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>

smatch warnings:
drivers/rtc/rtc-abx80x.c:561 sqw_set() error: uninitialized symbol 'retval'.

vim +/retval +561 drivers/rtc/rtc-abx80x.c

3f6d456de4f347 Kirill Kapranov 2021-03-29 527 static int sqw_set(struct i2c_client *client, const char *buf)
3f6d456de4f347 Kirill Kapranov 2021-03-29 528 {
3f6d456de4f347 Kirill Kapranov 2021-03-29 529 union abx8xx_reg_sqw reg_sqw;
3f6d456de4f347 Kirill Kapranov 2021-03-29 530 int retval;
3f6d456de4f347 Kirill Kapranov 2021-03-29 531
3f6d456de4f347 Kirill Kapranov 2021-03-29 532 reg_sqw.val = i2c_smbus_read_byte_data(client, ABX8XX_REG_SQW);
3f6d456de4f347 Kirill Kapranov 2021-03-29 533 if (reg_sqw.val < 0)
3f6d456de4f347 Kirill Kapranov 2021-03-29 534 goto err;

"retval" not set. Forgetting to set the error code is the canonical
bug for do nothing gotos like this.

3f6d456de4f347 Kirill Kapranov 2021-03-29 535
3f6d456de4f347 Kirill Kapranov 2021-03-29 536 if (sysfs_streq(buf, "none")) {
3f6d456de4f347 Kirill Kapranov 2021-03-29 537 reg_sqw.sqwe = 0;
3f6d456de4f347 Kirill Kapranov 2021-03-29 538 dev_info(&client->dev, "sqw output disabled\n");
3f6d456de4f347 Kirill Kapranov 2021-03-29 539 } else {
3f6d456de4f347 Kirill Kapranov 2021-03-29 540 int idx = __sysfs_match_string(sqfs, SQFS_COUNT, buf);
3f6d456de4f347 Kirill Kapranov 2021-03-29 541
3f6d456de4f347 Kirill Kapranov 2021-03-29 542 if (idx < 0)
3f6d456de4f347 Kirill Kapranov 2021-03-29 543 return idx;
^^^^^^^^^^^
These are direct returns. Just do direct returns everywhere (more
readably, fewer bugs).

3f6d456de4f347 Kirill Kapranov 2021-03-29 544
3f6d456de4f347 Kirill Kapranov 2021-03-29 545 if (abx80x_is_rc_mode(client) && !valid_for_rc_mode[idx])
3f6d456de4f347 Kirill Kapranov 2021-03-29 546 dev_warn(&client->dev, "sqw frequency %s valid only in xt mode\n",
3f6d456de4f347 Kirill Kapranov 2021-03-29 547 sqfs[idx]);
3f6d456de4f347 Kirill Kapranov 2021-03-29 548
3f6d456de4f347 Kirill Kapranov 2021-03-29 549 dev_info(&client->dev, "sqw output enabled @ %s\n", sqfs[idx]);
3f6d456de4f347 Kirill Kapranov 2021-03-29 550 reg_sqw.sqwe = 1;
3f6d456de4f347 Kirill Kapranov 2021-03-29 551 reg_sqw.sqws = idx;
3f6d456de4f347 Kirill Kapranov 2021-03-29 552 }
3f6d456de4f347 Kirill Kapranov 2021-03-29 553
3f6d456de4f347 Kirill Kapranov 2021-03-29 554 retval = i2c_smbus_write_byte_data(client, ABX8XX_REG_SQW, reg_sqw.val);
3f6d456de4f347 Kirill Kapranov 2021-03-29 555 if (retval < 0)
3f6d456de4f347 Kirill Kapranov 2021-03-29 556 goto err;
3f6d456de4f347 Kirill Kapranov 2021-03-29 557
3f6d456de4f347 Kirill Kapranov 2021-03-29 558 return 0;
3f6d456de4f347 Kirill Kapranov 2021-03-29 559 err:
3f6d456de4f347 Kirill Kapranov 2021-03-29 560 dev_err(&client->dev, "Failed to set SQW\n");
3f6d456de4f347 Kirill Kapranov 2021-03-29 @561 return retval;
^^^^^^^^^^^^^

3f6d456de4f347 Kirill Kapranov 2021-03-29 562

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx