On Thu, 2021-12-23 at 19:48 +0100, Jacopo Mondi wrote: > Hi Joe, > sorry to jump in No worries. It's all just a bikeshed and doesn't really matter to the correctness of the code. > On Thu, Dec 23, 2021 at 09:49:58AM -0800, Joe Perches wrote: > > On Thu, 2021-12-23 at 08:06 +0100, Krzysztof Hałasa wrote: > > > The driver has been extensively tested in an i.MX6-based system. > > > AR0521 is a 5.7 mm x 4.3 mm, 5 MPix RGGB MIPI/HiSPi BSI CMOS sensor > > > from On Semiconductor. > > > > trivial notes: > > > > > diff --git a/drivers/media/i2c/ar0521.c b/drivers/media/i2c/ar0521.c > > [] > > > +/* External clock (extclk) frequencies */ > > > +#define AR0521_EXTCLK_MIN (10 * 1000 * 1000) > > > > Generally, adding a prefix like AR0521_ to defines that are > > locally defined in a single file unnecessarily increases > > identifier length. > > > > It makes using short line lengths difficult. > > > > e.g. Using this identifier anywhere > > > > > +#define AR0521_REG_HISPI_CONTROL_STATUS_FRAMER_TEST_MODE_ENABLE 0x80 > > > > Many of the 80 column line lengths and line wrapping used in this > > file are not really nice to read. I believe you don't have to be > > strict about 80 column lines. > > > > Krzysztof first version had much longer lines, and in facts it has > been asked by me to reduce them to 80 cols. The media subsystem > requires to validate patches with > > ./scripts/checkpatch.pl --strict --max-line-length=80 > > We longly debated this and I believe it's now generally accepted to go > over 80 when it makes sense, but not regularly span to 120 cols like > in the previous version. IMO: Many of the lines here could be lengthened to < 100 to improve readability. > I think this 80-cols limit not being an hard limit anymore is doing > more worse than good, as each subsystem applies a different rule, and > I know how frustrating is for Krzysztof to be pushed in different > direction, as the same happened to me when I contributed to other > subsystems and I've been asked to span to 100 cols while I was trying > to stay in 80 no matter what. Up to you all. But there's a tension between long identifiers and short lines. And anything using a 55 character identifier basically guarantees that the code will exceed 80 columns. Using identifiers with 10 character or so is generally OK, but there are dozens of longer identifiers specific to this code. I'd suggest because of these long identifiers that the code be restricted to 100 columns, but not strictly at 80. And there are quite a few long lines in drivers/media/i2c and espcially for drivers/media/ A few of them are grotesquely long. Probably all of them are historic and don't warrant change. Just for i2c: $ git ls-files -- 'drivers/media/i2c/*.[ch]' | \ xargs awk '{print length($0); }' | \ sort -rn | uniq -c 2 143 1 141 1 123 4 118 2 114 1 111 1 110 1 109 1 107 1 105 4 104 2 102 3 101 1 100 2 99 11 98 7 97 8 96 4 95 11 94 8 93 19 92 13 91 28 90 20 89 28 88 39 87 18 86 33 85 42 84 86 83 38 82 47 81 167 80 110 79 155 78 363 77 230 76 219 75 217 74 427 73 695 72 471 71 538 70 525 69 679 68 661 67 1046 66 757 65 1002 64 942 63 1053 62 967 61 1018 60 1132 59 1307 58 1366 57 3206 56 1240 55 2191 54 1829 53 1719 52 1503 51 1795 50 1714 49 1640 48 1567 47 1550 46 1880 45 2155 44 1780 43 1880 42 1854 41 1962 40 2031 39 2009 38 2022 37 2240 36 2252 35 2152 34 2178 33 2074 32 2185 31 2462 30 2478 29 2186 28 1988 27 1846 26 1926 25 2177 24 2048 23 1804 22 1267 21 1414 20 1563 19 6154 18 3619 17 7222 16 1682 15 2685 14 3037 13 2142 12 1704 11 3013 10 3191 9 1609 8 230 7 461 6 571 5 878 4 2790 3 6524 2 7732 1 24729 0 And for all of drivers/media: $ git ls-files -- 'drivers/media/*.[ch]' | \ xargs awk '{print length($0);}' | \ sort -rn | uniq -c 1 338 1 314 1 268 1 261 1 255 1 254 1 242 1 234 1 228 1 213 1 207 1 205 1 198 2 197 3 192 2 188 2 177 1 174 2 172 2 169 3 168 2 167 1 166 1 165 1 164 3 163 2 162 2 161 2 160 6 158 10 157 3 156 2 155 3 154 2 153 12 152 8 151 49 150 4 148 2 147 3 146 3 145 5 144 5 143 1 142 6 141 7 140 8 139 6 138 10 137 14 136 13 135 14 134 13 133 11 132 7 131 6 130 15 129 21 128 17 127 13 126 10 125 13 124 12 123 25 122 20 121 25 120 15 119 18 118 20 117 23 116 30 115 23 114 26 113 35 112 35 111 40 110 60 109 50 108 72 107 42 106 47 105 105 104 72 103 90 102 110 101 144 100 79 99 122 98 226 97 644 96 115 95 135 94 135 93 166 92 210 91 227 90 218 89 208 88 279 87 292 86 1260 85 1122 84 879 83 1288 82 1489 81 2505 80 6241 79 3653 78 5268 77 2012 76 2168 75 2279 74 3297 73 4343 72 3741 71 4018 70 4360 69 4487 68 4433 67 6014 66 6098 65 6547 64 6661 63 7312 62 7684 61 7610 60 8157 59 9052 58 10047 57 12064 56 9904 55 11075 54 11271 53 13259 52 11585 51 15036 50 13930 49 15159 48 14221 47 13349 46 14243 45 15887 44 17829 43 16620 42 17759 41 17569 40 16653 39 17386 38 17480 37 18296 36 18205 35 18782 34 18352 33 18137 32 19556 31 19229 30 19403 29 19570 28 19447 27 19581 26 19255 25 19300 24 17038 23 18523 22 15609 21 16188 20 14634 19 19426 18 20979 17 21548 16 13476 15 16713 14 18914 13 17577 12 12828 11 19525 10 21665 9 13912 8 3261 7 5375 6 6756 5 8260 4 23448 3 48708 2 55786 1 182329 0