On Thu, 8 Aug 2024 16:52:09 +0800 kernel test robot <lkp@xxxxxxxxx> wrote: > 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); Probably a case of the compiler somehow failing to squash the local variable. I'd just go with val = FIELD_PREP(AD4695_REG_TEMP_CTRL_TEMP_EN, 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 >
