Re: [V3] tty: serial: qcom-geni-serial: Fix get_clk_div_rate() which otherwise could return a sub-optimal clock rate.

From: kernel test robot
Date: Fri Jul 08 2022 - 00:48:47 EST


Hi Vijaya,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on tty/tty-testing]
[also build test WARNING on linus/master v5.19-rc5 next-20220707]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Vijaya-Krishna-Nivarthi/tty-serial-qcom-geni-serial-Fix-get_clk_div_rate-which-otherwise-could-return-a-sub-optimal-clock-rate/20220708-031921
base: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty.git tty-testing
config: nios2-randconfig-r024-20220707 (https://download.01.org/0day-ci/archive/20220708/202207081234.3SPgl4KO-lkp@xxxxxxxxx/config)
compiler: nios2-linux-gcc (GCC) 11.3.0
reproduce (this is a W=1 build):
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# https://github.com/intel-lab-lkp/linux/commit/fbd8a1a4b7d91ea5caa048e4557ab18b0d08ea86
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Vijaya-Krishna-Nivarthi/tty-serial-qcom-geni-serial-Fix-get_clk_div_rate-which-otherwise-could-return-a-sub-optimal-clock-rate/20220708-031921
git checkout fbd8a1a4b7d91ea5caa048e4557ab18b0d08ea86
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.3.0 make.cross W=1 O=build_dir ARCH=nios2 SHELL=/bin/bash drivers/tty/serial/

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@xxxxxxxxx>

All warnings (new ones prefixed by >>):

In file included from include/linux/kernel.h:29,
from include/linux/clk.h:13,
from drivers/tty/serial/qcom_geni_serial.c:4:
drivers/tty/serial/qcom_geni_serial.c: In function 'get_clk_div_rate':
>> drivers/tty/serial/qcom_geni_serial.c:1006:26: warning: format '%lu' expects argument of type 'long unsigned int', but argument 5 has type 'unsigned int' [-Wformat=]
1006 | pr_debug("desired_clk-%lu, ser_clk-%lu, clk_div-%lu\n",
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
include/linux/printk.h:370:21: note: in definition of macro 'pr_fmt'
370 | #define pr_fmt(fmt) fmt
| ^~~
include/linux/dynamic_debug.h:152:9: note: in expansion of macro '__dynamic_func_call'
152 | __dynamic_func_call(__UNIQUE_ID(ddebug), fmt, func, ##__VA_ARGS__)
| ^~~~~~~~~~~~~~~~~~~
include/linux/dynamic_debug.h:162:9: note: in expansion of macro '_dynamic_func_call'
162 | _dynamic_func_call(fmt, __dynamic_pr_debug, \
| ^~~~~~~~~~~~~~~~~~
include/linux/printk.h:604:9: note: in expansion of macro 'dynamic_pr_debug'
604 | dynamic_pr_debug(fmt, ##__VA_ARGS__)
| ^~~~~~~~~~~~~~~~
drivers/tty/serial/qcom_geni_serial.c:1006:17: note: in expansion of macro 'pr_debug'
1006 | pr_debug("desired_clk-%lu, ser_clk-%lu, clk_div-%lu\n",
| ^~~~~~~~
drivers/tty/serial/qcom_geni_serial.c:1006:67: note: format string is defined here
1006 | pr_debug("desired_clk-%lu, ser_clk-%lu, clk_div-%lu\n",
| ~~^
| |
| long unsigned int
| %u


vim +1006 drivers/tty/serial/qcom_geni_serial.c

983
984 static unsigned long get_clk_div_rate(struct clk *clk, unsigned int baud,
985 unsigned int sampling_rate, unsigned int *clk_div)
986 {
987 unsigned long ser_clk;
988 unsigned long desired_clk;
989
990 desired_clk = baud * sampling_rate;
991 if (!desired_clk) {
992 pr_err("%s: Invalid frequency\n", __func__);
993 return 0;
994 }
995
996 /*
997 * try to find a clock rate within 2% tolerance, then within
998 */
999 ser_clk = find_clk_rate_in_tol(clk, desired_clk, clk_div, 2);
1000 if (!ser_clk)
1001 ser_clk = find_clk_rate_in_tol(clk, desired_clk, clk_div, 5);
1002
1003 if (!ser_clk)
1004 pr_err("Couldn't find suitable clock rate for %lu\n", desired_clk);
1005 else
> 1006 pr_debug("desired_clk-%lu, ser_clk-%lu, clk_div-%lu\n",
1007 desired_clk, ser_clk, *clk_div);
1008
1009 return ser_clk;
1010 }
1011

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