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 unsigned short i; 31 irqreturn_t ret = IRQ_NONE; 32 33 dmaisr = readl(chip->regs + HSU_PCI_DMAISR); 34 for (i = 0; i < chip->pdata->nr_channels; i++) { 35 if (dmaisr & 0x1) 36 ret |= hsu_dma_irq(chip, i); 37 dmaisr >>= 1; 38 } 39 40 return ret; 41 } 42 43 static int hsu_pci_probe(struct pci_dev *pdev, const struct pci_device_id *id) 44 { 45 struct hsu_dma_chip *chip; 46 int ret; 47 48 ret = pcim_enable_device(pdev); 49 if (ret) 50 return ret; 51 52 ret = pcim_iomap_regions(pdev, BIT(0), pci_name(pdev)); 53 if (ret) { 54 dev_err(&pdev->dev, "I/O memory remapping failed\n"); 55 return ret; 56 } 57 58 pci_set_master(pdev); 59 pci_try_set_mwi(pdev); 60 61 ret = pci_set_dma_mask(pdev, DMA_BIT_MASK(32)); 62 if (ret) 63 return ret; 64 65 ret = pci_set_consistent_dma_mask(pdev, DMA_BIT_MASK(32)); 66 if (ret) 67 return ret; 68 69 chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL); 70 if (!chip) 71 return -ENOMEM; 72 73 chip->dev = &pdev->dev; 74 chip->regs = pcim_iomap_table(pdev)[0]; 75 chip->length = pci_resource_len(pdev, 0); 76 chip->offset = HSU_PCI_CHAN_OFFSET; 77 chip->irq = pdev->irq; 78 79 pci_enable_msi(pdev); 80 81 ret = hsu_dma_probe(chip); 82 if (ret) 83 return ret; 84 85 ret = request_irq(chip->irq, hsu_pci_irq, 0, "hsu_dma_pci", chip); 86 if (ret) 87 goto err_register_irq; 88 89 pci_set_drvdata(pdev, chip); 90 91 return 0; 92 93 err_register_irq: 94 hsu_dma_remove(chip); 95 return ret; 96 } 97 98 static void hsu_pci_remove(struct pci_dev *pdev) 99 { 100 struct hsu_dma_chip *chip = pci_get_drvdata(pdev); 101 102 free_irq(chip->irq, chip); 103 hsu_dma_remove(chip); 104 } 105 106 static const struct pci_device_id hsu_pci_id_table[] = { 107 { PCI_VDEVICE(INTEL, 0x081e), 0 }, 108 { PCI_VDEVICE(INTEL, 0x1192), 0 }, 109 { } 110 }; 111 MODULE_DEVICE_TABLE(pci, hsu_pci_id_table); 112 113 static struct pci_driver hsu_pci_driver = { 114 .name = "hsu_dma_pci", 115 .id_table = hsu_pci_id_table, 116 .probe = hsu_pci_probe, 117 .remove = hsu_pci_remove, 118 }; 119 120 module_pci_driver(hsu_pci_driver); 121 122 MODULE_LICENSE("GPL v2"); 123 MODULE_DESCRIPTION("High Speed UART DMA PCI driver"); 124 MODULE_AUTHOR("Andy Shevchenko <andriy.shevchenko@linux.intel.com>"); 125