iio: adc: ad_sigma_delta: add SPI offload support

+133 -48

2 changed files

expand all

drivers

iio

adc

ad_sigma_delta.c

include

linux

iio

adc

ad_sigma_delta.h

+119 -48

drivers/iio/adc/ad_sigma_delta.c

··· 20 20 #include <linux/module.h> 21 21 #include <linux/property.h> 22 22 #include <linux/slab.h> 23 + #include <linux/spi/offload/consumer.h> 23 24 #include <linux/spi/spi.h> 24 25 #include <linux/spinlock.h> 25 26 #include <linux/string.h> ··· 28 27 #include <linux/unaligned.h> 29 28 30 29 #include <linux/iio/adc/ad_sigma_delta.h> 30 + #include <linux/iio/buffer-dmaengine.h> 31 31 #include <linux/iio/buffer.h> 32 32 #include <linux/iio/iio.h> 33 33 #include <linux/iio/trigger_consumer.h> ··· 469 467 struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); 470 468 const struct iio_scan_type *scan_type = &indio_dev->channels[0].scan_type; 471 469 struct spi_transfer *xfer = sigma_delta->sample_xfer; 472 - unsigned int i, slot, samples_buf_size; 473 - unsigned int channel, scan_size; 470 + unsigned int i, slot, channel; 474 471 u8 *samples_buf; 475 472 int ret; 476 473 ··· 497 496 sigma_delta->active_slots = slot; 498 497 sigma_delta->current_slot = 0; 499 498 500 - if (sigma_delta->active_slots > 1) { 501 - ret = ad_sigma_delta_append_status(sigma_delta, true); 502 - if (ret) 503 - return ret; 499 + if (ad_sigma_delta_has_spi_offload(sigma_delta)) { 500 + xfer[1].offload_flags = SPI_OFFLOAD_XFER_RX_STREAM; 501 + xfer[1].bits_per_word = scan_type->realbits; 502 + xfer[1].len = spi_bpw_to_bytes(scan_type->realbits); 503 + } else { 504 + unsigned int samples_buf_size, scan_size; 505 + 506 + if (sigma_delta->active_slots > 1) { 507 + ret = ad_sigma_delta_append_status(sigma_delta, true); 508 + if (ret) 509 + return ret; 510 + } 511 + 512 + samples_buf_size = 513 + ALIGN(slot * BITS_TO_BYTES(scan_type->storagebits), 514 + sizeof(s64)); 515 + samples_buf_size += sizeof(s64); 516 + samples_buf = devm_krealloc(&sigma_delta->spi->dev, 517 + sigma_delta->samples_buf, 518 + samples_buf_size, GFP_KERNEL); 519 + if (!samples_buf) 520 + return -ENOMEM; 521 + 522 + sigma_delta->samples_buf = samples_buf; 523 + scan_size = BITS_TO_BYTES(scan_type->realbits + scan_type->shift); 524 + /* For 24-bit data, there is an extra byte of padding. */ 525 + xfer[1].rx_buf = &sigma_delta->rx_buf[scan_size == 3 ? 1 : 0]; 526 + xfer[1].len = scan_size + (sigma_delta->status_appended ? 1 : 0); 504 527 } 505 - 506 - samples_buf_size = ALIGN(slot * BITS_TO_BYTES(scan_type->storagebits), 507 - sizeof(s64)); 508 - samples_buf_size += sizeof(s64); 509 - samples_buf = devm_krealloc(&sigma_delta->spi->dev, sigma_delta->samples_buf, 510 - samples_buf_size, GFP_KERNEL); 511 - if (!samples_buf) 512 - return -ENOMEM; 513 - 514 - sigma_delta->samples_buf = samples_buf; 515 - scan_size = BITS_TO_BYTES(scan_type->realbits + scan_type->shift); 516 - /* For 24-bit data, there is an extra byte of padding. */ 517 - xfer[1].rx_buf = &sigma_delta->rx_buf[scan_size == 3 ? 1 : 0]; 518 - xfer[1].len = scan_size + (sigma_delta->status_appended ? 1 : 0); 519 528 xfer[1].cs_change = 1; 520 529 521 530 if (sigma_delta->info->has_registers) { ··· 540 529 spi_message_init_with_transfers(&sigma_delta->sample_msg, 541 530 &xfer[1], 1); 542 531 } 532 + 533 + sigma_delta->sample_msg.offload = sigma_delta->offload; 543 534 544 535 ret = spi_optimize_message(sigma_delta->spi, &sigma_delta->sample_msg); 545 536 if (ret) ··· 559 546 if (ret) 560 547 goto err_unlock; 561 548 562 - ad_sd_enable_irq(sigma_delta); 549 + if (ad_sigma_delta_has_spi_offload(sigma_delta)) { 550 + struct spi_offload_trigger_config config = { 551 + .type = SPI_OFFLOAD_TRIGGER_DATA_READY, 552 + }; 553 + 554 + ret = spi_offload_trigger_enable(sigma_delta->offload, 555 + sigma_delta->offload_trigger, 556 + &config); 557 + if (ret) 558 + goto err_unlock; 559 + } else { 560 + ad_sd_enable_irq(sigma_delta); 561 + } 563 562 564 563 return 0; 565 564 ··· 586 561 { 587 562 struct ad_sigma_delta *sigma_delta = iio_device_get_drvdata(indio_dev); 588 563 589 - reinit_completion(&sigma_delta->completion); 590 - wait_for_completion_timeout(&sigma_delta->completion, HZ); 564 + if (ad_sigma_delta_has_spi_offload(sigma_delta)) { 565 + spi_offload_trigger_disable(sigma_delta->offload, 566 + sigma_delta->offload_trigger); 567 + } else { 568 + reinit_completion(&sigma_delta->completion); 569 + wait_for_completion_timeout(&sigma_delta->completion, HZ); 591 570 592 - ad_sd_disable_irq(sigma_delta); 571 + ad_sd_disable_irq(sigma_delta); 572 + } 593 573 594 574 sigma_delta->keep_cs_asserted = false; 595 575 ad_sigma_delta_set_mode(sigma_delta, AD_SD_MODE_IDLE); ··· 709 679 if ((!sigma_delta->rdy_gpiod || gpiod_get_value(sigma_delta->rdy_gpiod)) && 710 680 ad_sd_disable_irq(sigma_delta)) { 711 681 complete(&sigma_delta->completion); 712 - iio_trigger_poll(sigma_delta->trig); 682 + if (sigma_delta->trig) 683 + iio_trigger_poll(sigma_delta->trig); 713 684 714 685 return IRQ_HANDLED; 715 686 } ··· 743 712 unsigned long irq_flags = irq_get_trigger_type(sigma_delta->irq_line); 744 713 int ret; 745 714 746 - if (dev != &sigma_delta->spi->dev) { 747 - dev_err(dev, "Trigger parent should be '%s', got '%s'\n", 748 - dev_name(dev), dev_name(&sigma_delta->spi->dev)); 749 - return -EFAULT; 750 - } 751 - 752 - sigma_delta->trig = devm_iio_trigger_alloc(dev, "%s-dev%d", indio_dev->name, 753 - iio_device_id(indio_dev)); 754 - if (sigma_delta->trig == NULL) 755 - return -ENOMEM; 756 - 757 715 init_completion(&sigma_delta->completion); 758 716 759 717 sigma_delta->irq_dis = true; ··· 762 742 if (ret) 763 743 return ret; 764 744 765 - iio_trigger_set_drvdata(sigma_delta->trig, sigma_delta); 745 + if (ad_sigma_delta_has_spi_offload(sigma_delta)) { 746 + sigma_delta->offload_trigger = 747 + devm_spi_offload_trigger_get(dev, sigma_delta->offload, 748 + SPI_OFFLOAD_TRIGGER_DATA_READY); 749 + if (IS_ERR(sigma_delta->offload_trigger)) 750 + return dev_err_probe(dev, PTR_ERR(sigma_delta->offload_trigger), 751 + "Failed to get SPI offload trigger\n"); 752 + } else { 753 + if (dev != &sigma_delta->spi->dev) 754 + return dev_err_probe(dev, -EFAULT, 755 + "Trigger parent should be '%s', got '%s'\n", 756 + dev_name(dev), dev_name(&sigma_delta->spi->dev)); 766 757 767 - ret = devm_iio_trigger_register(dev, sigma_delta->trig); 768 - if (ret) 769 - return ret; 758 + sigma_delta->trig = devm_iio_trigger_alloc(dev, "%s-dev%d", 759 + indio_dev->name, iio_device_id(indio_dev)); 760 + if (!sigma_delta->trig) 761 + return -ENOMEM; 770 762 771 - /* select default trigger */ 772 - indio_dev->trig = iio_trigger_get(sigma_delta->trig); 763 + iio_trigger_set_drvdata(sigma_delta->trig, sigma_delta); 764 + 765 + ret = devm_iio_trigger_register(dev, sigma_delta->trig); 766 + if (ret) 767 + return ret; 768 + 769 + /* select default trigger */ 770 + indio_dev->trig = iio_trigger_get(sigma_delta->trig); 771 + } 773 772 774 773 return 0; 775 774 } ··· 808 769 if (!sigma_delta->slots) 809 770 return -ENOMEM; 810 771 811 - ret = devm_iio_triggered_buffer_setup(dev, indio_dev, 812 - &iio_pollfunc_store_time, 813 - &ad_sd_trigger_handler, 814 - &ad_sd_buffer_setup_ops); 815 - if (ret) 816 - return ret; 772 + if (ad_sigma_delta_has_spi_offload(sigma_delta)) { 773 + struct dma_chan *rx_dma; 774 + 775 + rx_dma = devm_spi_offload_rx_stream_request_dma_chan(dev, 776 + sigma_delta->offload); 777 + if (IS_ERR(rx_dma)) 778 + return dev_err_probe(dev, PTR_ERR(rx_dma), 779 + "Failed to get RX DMA channel\n"); 780 + 781 + ret = devm_iio_dmaengine_buffer_setup_with_handle(dev, indio_dev, 782 + rx_dma, IIO_BUFFER_DIRECTION_IN); 783 + if (ret) 784 + return dev_err_probe(dev, ret, "Cannot setup DMA buffer\n"); 785 + 786 + indio_dev->setup_ops = &ad_sd_buffer_setup_ops; 787 + } else { 788 + ret = devm_iio_triggered_buffer_setup(dev, indio_dev, 789 + &iio_pollfunc_store_time, 790 + &ad_sd_trigger_handler, 791 + &ad_sd_buffer_setup_ops); 792 + if (ret) 793 + return ret; 794 + } 817 795 818 796 return devm_ad_sd_probe_trigger(dev, indio_dev); 819 797 } ··· 893 837 return sigma_delta->irq_line; 894 838 } 895 839 840 + if (info->supports_spi_offload) { 841 + struct spi_offload_config offload_config = { 842 + .capability_flags = SPI_OFFLOAD_CAP_TRIGGER | 843 + SPI_OFFLOAD_CAP_RX_STREAM_DMA, 844 + }; 845 + int ret; 846 + 847 + sigma_delta->offload = devm_spi_offload_get(&spi->dev, spi, 848 + &offload_config); 849 + ret = PTR_ERR_OR_ZERO(sigma_delta->offload); 850 + if (ret && ret != -ENODEV) 851 + return dev_err_probe(&spi->dev, ret, "Failed to get SPI offload\n"); 852 + } 853 + 896 854 iio_device_set_drvdata(indio_dev, sigma_delta); 897 855 898 856 return 0; ··· 916 846 MODULE_AUTHOR("Lars-Peter Clausen <lars@metafoo.de>"); 917 847 MODULE_DESCRIPTION("Analog Devices Sigma-Delta ADCs"); 918 848 MODULE_LICENSE("GPL v2"); 849 + MODULE_IMPORT_NS("IIO_DMAENGINE_BUFFER");

+14

include/linux/iio/adc/ad_sigma_delta.h

··· 31 31 struct device; 32 32 struct gpio_desc; 33 33 struct iio_dev; 34 + struct spi_offload; 35 + struct spi_offload_trigger; 34 36 35 37 /** 36 38 * struct ad_sigma_delta_info - Sigma Delta driver specific callbacks and options ··· 49 47 * @has_registers: true if the device has writable and readable registers, false 50 48 * if there is just one read-only sample data shift register. 51 49 * @has_named_irqs: Set to true if there is more than one IRQ line. 50 + * @supports_spi_offload: Set to true if the driver supports SPI offload. Often 51 + * special considerations are needed for scan_type and other channel 52 + * info, so individual drivers have to set this to let the core 53 + * code know that it can use SPI offload if it is available. 52 54 * @addr_shift: Shift of the register address in the communications register. 53 55 * @read_mask: Mask for the communications register having the read bit set. 54 56 * @status_ch_mask: Mask for the channel number stored in status register. ··· 71 65 int (*postprocess_sample)(struct ad_sigma_delta *, unsigned int raw_sample); 72 66 bool has_registers; 73 67 bool has_named_irqs; 68 + bool supports_spi_offload; 74 69 unsigned int addr_shift; 75 70 unsigned int read_mask; 76 71 unsigned int status_ch_mask; ··· 115 108 struct spi_message sample_msg; 116 109 struct spi_transfer sample_xfer[2]; 117 110 u8 *samples_buf; 111 + struct spi_offload *offload; 112 + struct spi_offload_trigger *offload_trigger; 118 113 119 114 /* 120 115 * DMA (thus cache coherency maintenance) requires the ··· 129 120 u8 rx_buf[16] __aligned(8); 130 121 u8 sample_addr; 131 122 }; 123 + 124 + static inline bool ad_sigma_delta_has_spi_offload(struct ad_sigma_delta *sd) 125 + { 126 + return sd->offload != NULL; 127 + } 132 128 133 129 static inline int ad_sigma_delta_set_channel(struct ad_sigma_delta *sd, 134 130 unsigned int channel)

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