1 /* 2 * PCI driver for the High Speed UART DMA 3 * 4 * Copyright (C) 2015 Intel Corporation 5 * Author: Andy Shevchenko <andriy.shevchenko@linux.intel.com> 6 * 7 * Partially based on the bits found in drivers/tty/serial/mfd.c. 8 * 9 * This program is free software; you can redistribute it and/or modify 10 * it under the terms of the GNU General Public License version 2 as 11 * published by the Free Software Foundation. 12 */ 13 14 #include <linux/bitops.h> 15 #include <linux/device.h> 16 #include <linux/module.h> 17 #include <linux/pci.h> 18 19 #include "hsu.h" 20 21 #define HSU_PCI_DMASR 0x00 22 #define HSU_PCI_DMAISR 0x04 23 24 #define HSU_PCI_CHAN_OFFSET 0x100 25 26 static irqreturn_t hsu_pci_irq(int irq, void *dev) 27 { 28 struct hsu_dma_chip *chip = dev; 29 u32 dmaisr; 30 u32 status; 31 unsigned short i; 32 int ret = 0; 33 int err; 34 35 dmaisr = readl(chip->regs + HSU_PCI_DMAISR); 36 for (i = 0; i < chip->hsu->nr_channels; i++) { 37 if (dmaisr & 0x1) { 38 err = hsu_dma_get_status(chip, i, &status); 39 if (err > 0) 40 ret |= 1; 41 else if (err == 0) 42 ret |= hsu_dma_do_irq(chip, i, status); 43 } 44 dmaisr >>= 1; 45 } 46 47 return IRQ_RETVAL(ret); 48 } 49 50 static int hsu_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) 51 { 52 struct hsu_dma_chip *chip; 53 int ret; 54 55 ret = pcim_enable_device(pdev); 56 if (ret) 57 return ret; 58 59 ret = pcim_iomap_regions(pdev, BIT(0), pci_name(pdev)); 60 if (ret) { 61 dev_err(&pdev->dev, "I/O memory remapping failed\n"); 62 return ret; 63 } 64 65 pci_set_master(pdev); 66 pci_try_set_mwi(pdev); 67 68 ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32)); 69 if (ret) 70 return ret; 71 72 ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32)); 73 if (ret) 74 return ret; 75 76 chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL); 77 if (!chip) 78 return -ENOMEM; 79 80 ret = pci_alloc_irq_vectors(pdev, 1, 1, PCI_IRQ_ALL_TYPES); 81 if (ret < 0) 82 return ret; 83 84 chip->dev = &pdev->dev; 85 chip->regs = pcim_iomap_table(pdev)[0]; 86 chip->length = pci_resource_len(pdev, 0); 87 chip->offset = HSU_PCI_CHAN_OFFSET; 88 chip->irq = pci_irq_vector(pdev, 0); 89 90 ret = hsu_dma_probe(chip); 91 if (ret) 92 return ret; 93 94 ret = request_irq(chip->irq, hsu_pci_irq, 0, "hsu_dma_pci", chip); 95 if (ret) 96 goto err_register_irq; 97 98 pci_set_drvdata(pdev, chip); 99 100 return 0; 101 102 err_register_irq: 103 hsu_dma_remove(chip); 104 return ret; 105 } 106 107 static void hsu_pci_remove(struct pci_dev *pdev) 108 { 109 struct hsu_dma_chip *chip = pci_get_drvdata(pdev); 110 111 free_irq(chip->irq, chip); 112 hsu_dma_remove(chip); 113 } 114 115 static const struct pci_device_id hsu_pci_id_table[] = { 116 { PCI_VDEVICE(INTEL, 0x081e), 0 }, 117 { PCI_VDEVICE(INTEL, 0x1192), 0 }, 118 { } 119 }; 120 MODULE_DEVICE_TABLE(pci, hsu_pci_id_table); 121 122 static struct pci_driver hsu_pci_driver = { 123 .name = "hsu_dma_pci", 124 .id_table = hsu_pci_id_table, 125 .probe = hsu_pci_probe, 126 .remove = hsu_pci_remove, 127 }; 128 129 module_pci_driver(hsu_pci_driver); 130 131 MODULE_LICENSE("GPL v2"); 132 MODULE_DESCRIPTION("High Speed UART DMA PCI driver"); 133 MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>"); 134