Hi David, kernel test robot noticed the following build warnings: [auto build test WARNING on 7cad163c39cb642ed587d3eeb37a5637ee02740f] url: https://github.com/intel-lab-lkp/linux/commits/David-Lechner/iio-adc-ad4695-implement-triggered-buffer/20240808-063333 base: 7cad163c39cb642ed587d3eeb37a5637ee02740f patch link: https://lore.kernel.org/r/20240807-iio-adc-ad4695-buffered-read-v1-1-bdafc39b2283%40baylibre.com patch subject: [PATCH 1/2] iio: adc: ad4695: implement triggered buffer config: hexagon-allmodconfig (https://download.01.org/0day-ci/archive/20240808/202408081623.ua9EBfoZ-lkp@xxxxxxxxx/config) compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project 408d82d352eb98e2d0a804c66d359cd7a49228fe) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240808/202408081623.ua9EBfoZ-lkp@xxxxxxxxx/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202408081623.ua9EBfoZ-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): In file included from drivers/iio/adc/ad4695.c:24: In file included from include/linux/iio/triggered_buffer.h:6: In file included from include/linux/interrupt.h:11: In file included from include/linux/hardirq.h:11: In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1: In file included from include/asm-generic/hardirq.h:17: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:14: In file included from arch/hexagon/include/asm/io.h:328: include/asm-generic/io.h:548:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 548 | val = __raw_readb(PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:561:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 561 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr)); | ~~~~~~~~~~ ^ include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu' 37 | #define __le16_to_cpu(x) ((__force __u16)(__le16)(x)) | ^ In file included from drivers/iio/adc/ad4695.c:24: In file included from include/linux/iio/triggered_buffer.h:6: In file included from include/linux/interrupt.h:11: In file included from include/linux/hardirq.h:11: In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1: In file included from include/asm-generic/hardirq.h:17: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:14: In file included from arch/hexagon/include/asm/io.h:328: include/asm-generic/io.h:574:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 574 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr)); | ~~~~~~~~~~ ^ include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu' 35 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x)) | ^ In file included from drivers/iio/adc/ad4695.c:24: In file included from include/linux/iio/triggered_buffer.h:6: In file included from include/linux/interrupt.h:11: In file included from include/linux/hardirq.h:11: In file included from ./arch/hexagon/include/generated/asm/hardirq.h:1: In file included from include/asm-generic/hardirq.h:17: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:14: In file included from arch/hexagon/include/asm/io.h:328: include/asm-generic/io.h:585:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 585 | __raw_writeb(value, PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:595:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 595 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:605:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 605 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr); | ~~~~~~~~~~ ^ In file included from drivers/iio/adc/ad4695.c:28: In file included from include/linux/regulator/consumer.h:35: In file included from include/linux/suspend.h:5: In file included from include/linux/swap.h:9: In file included from include/linux/memcontrol.h:21: In file included from include/linux/mm.h:2228: include/linux/vmstat.h:514:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion] 514 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_" | ~~~~~~~~~~~ ^ ~~~ >> drivers/iio/adc/ad4695.c:454:8: warning: result of comparison of constant 18446744073709551615 with expression of type 'typeof (_Generic((mask), char: (unsigned char)0, unsigned char: (unsigned char)0, signed char: (unsigned char)0, unsigned short: (unsigned short)0, short: (unsigned short)0, unsigned int: (unsigned int)0, int: (unsigned int)0, unsigned long: (unsigned long)0, long: (unsigned long)0, unsigned long long: (unsigned long long)0, long long: (unsigned long long)0, default: (mask)))' (aka 'unsigned int') is always false [-Wtautological-constant-out-of-range-compare] 454 | val = FIELD_PREP(mask, temp_chan_en ? 1 : 0); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/bitfield.h:115:3: note: expanded from macro 'FIELD_PREP' 115 | __BF_FIELD_CHECK(_mask, 0ULL, _val, "FIELD_PREP: "); \ | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/bitfield.h:72:53: note: expanded from macro '__BF_FIELD_CHECK' 72 | BUILD_BUG_ON_MSG(__bf_cast_unsigned(_mask, _mask) > \ | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~ 73 | __bf_cast_unsigned(_reg, ~0ull), \ | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 74 | _pfx "type of reg too small for mask"); \ | ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/build_bug.h:39:58: note: expanded from macro 'BUILD_BUG_ON_MSG' 39 | #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) | ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~ include/linux/compiler_types.h:510:22: note: expanded from macro 'compiletime_assert' 510 | _compiletime_assert(condition, msg, __compiletime_assert_, __COUNTER__) | ~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/compiler_types.h:498:23: note: expanded from macro '_compiletime_assert' 498 | __compiletime_assert(condition, msg, prefix, suffix) | ~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ include/linux/compiler_types.h:490:9: note: expanded from macro '__compiletime_assert' 490 | if (!(condition)) \ | ^~~~~~~~~ 8 warnings generated. vim +454 drivers/iio/adc/ad4695.c 373 374 static int ad4695_buffer_preenable(struct iio_dev *indio_dev) 375 { 376 struct ad4695_state *st = iio_priv(indio_dev); 377 struct spi_transfer *xfer; 378 u8 temp_chan_bit = st->chip_info->num_voltage_inputs; 379 bool temp_chan_en = false; 380 u32 reg, mask, val, bit, num_xfer, num_slots; 381 int ret; 382 383 /* 384 * We are using the advanced sequencer since it is the only way to read 385 * multiple channels that allows individual configuration of each 386 * voltage input channel. Slot 0 in the advanced sequencer is used to 387 * account for the gap between trigger polls - we don't read data from 388 * this slot. Each enabled voltage channel is assigned a slot starting 389 * with slot 1. 390 */ 391 num_slots = 1; 392 393 memset(st->buf_read_xfer, 0, sizeof(st->buf_read_xfer)); 394 395 /* First xfer is only to trigger conversion of slot 1, so no rx. */ 396 xfer = &st->buf_read_xfer[0]; 397 xfer->cs_change = 1; 398 xfer->delay.value = AD4695_T_CNVL_NS; 399 xfer->delay.unit = SPI_DELAY_UNIT_NSECS; 400 xfer->cs_change_delay.value = AD4695_T_CONVERT_NS; 401 xfer->cs_change_delay.unit = SPI_DELAY_UNIT_NSECS; 402 num_xfer = 1; 403 404 iio_for_each_active_channel(indio_dev, bit) { 405 xfer = &st->buf_read_xfer[num_xfer]; 406 xfer->bits_per_word = 16; 407 xfer->rx_buf = &st->buf[(num_xfer - 1) * 2]; 408 xfer->len = 2; 409 xfer->cs_change = 1; 410 xfer->cs_change_delay.value = AD4695_T_CONVERT_NS; 411 xfer->cs_change_delay.unit = SPI_DELAY_UNIT_NSECS; 412 413 if (bit == temp_chan_bit) { 414 temp_chan_en = true; 415 } else { 416 reg = AD4695_REG_AS_SLOT(num_slots); 417 val = FIELD_PREP(AD4695_REG_AS_SLOT_INX, bit); 418 419 ret = regmap_write(st->regmap, reg, val); 420 if (ret) 421 return ret; 422 423 num_slots++; 424 } 425 426 num_xfer++; 427 } 428 429 /* 430 * Don't keep CS asserted after last xfer. Also triggers conversion of 431 * slot 0. 432 */ 433 xfer->cs_change = 0; 434 435 /** 436 * The advanced sequencer requires that at least 2 slots are enabled. 437 * Since slot 0 is always used for other purposes, we need only 1 438 * enabled voltage channel to meet this requirement. This error will 439 * only happen if only the temperature channel is enabled. 440 */ 441 if (num_slots < 2) { 442 dev_err_ratelimited(&indio_dev->dev, 443 "Buffered read requires at least 1 voltage channel enabled\n"); 444 return -EINVAL; 445 } 446 447 /* 448 * Temperature channel isn't included in the sequence, but rather 449 * controlled by setting a bit in the TEMP_CTRL register. 450 */ 451 452 reg = AD4695_REG_TEMP_CTRL; 453 mask = AD4695_REG_TEMP_CTRL_TEMP_EN; > 454 val = FIELD_PREP(mask, temp_chan_en ? 1 : 0); 455 456 ret = regmap_update_bits(st->regmap, reg, mask, val); 457 if (ret) 458 return ret; 459 460 spi_message_init_with_transfers(&st->buf_read_msg, st->buf_read_xfer, 461 num_xfer); 462 463 ret = spi_optimize_message(st->spi, &st->buf_read_msg); 464 if (ret) 465 return ret; 466 467 /* This triggers conversion of slot 0. */ 468 ret = ad4695_enter_advanced_sequencer_mode(st, num_slots); 469 if (ret) { 470 spi_unoptimize_message(&st->buf_read_msg); 471 return ret; 472 } 473 474 return 0; 475 } 476 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki