1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * Cavium ThunderX SPI driver. 4 * 5 * Copyright (C) 2016 Cavium Inc. 6 * Authors: Jan Glauber <jglauber@cavium.com> 7 */ 8 9 #include <linux/module.h> 10 #include <linux/pci.h> 11 #include <linux/spi/spi.h> 12 13 #include "spi-cavium.h" 14 15 #define DRV_NAME "spi-thunderx" 16 17 #define SYS_FREQ_DEFAULT 700000000 /* 700 Mhz */ 18 19 static int thunderx_spi_probe(struct pci_dev *pdev, 20 const struct pci_device_id *ent) 21 { 22 struct device *dev = &pdev->dev; 23 struct spi_master *master; 24 struct octeon_spi *p; 25 int ret; 26 27 master = spi_alloc_master(dev, sizeof(struct octeon_spi)); 28 if (!master) 29 return -ENOMEM; 30 31 p = spi_master_get_devdata(master); 32 33 ret = pcim_enable_device(pdev); 34 if (ret) 35 goto error; 36 37 ret = pci_request_regions(pdev, DRV_NAME); 38 if (ret) 39 goto error; 40 41 p->register_base = pcim_iomap(pdev, 0, pci_resource_len(pdev, 0)); 42 if (!p->register_base) { 43 ret = -EINVAL; 44 goto error; 45 } 46 47 p->regs.config = 0x1000; 48 p->regs.status = 0x1008; 49 p->regs.tx = 0x1010; 50 p->regs.data = 0x1080; 51 52 p->clk = devm_clk_get(dev, NULL); 53 if (IS_ERR(p->clk)) { 54 ret = PTR_ERR(p->clk); 55 goto error; 56 } 57 58 ret = clk_prepare_enable(p->clk); 59 if (ret) 60 goto error; 61 62 p->sys_freq = clk_get_rate(p->clk); 63 if (!p->sys_freq) 64 p->sys_freq = SYS_FREQ_DEFAULT; 65 dev_info(dev, "Set system clock to %u\n", p->sys_freq); 66 67 master->flags = SPI_MASTER_HALF_DUPLEX; 68 master->num_chipselect = 4; 69 master->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH | 70 SPI_LSB_FIRST | SPI_3WIRE; 71 master->transfer_one_message = octeon_spi_transfer_one_message; 72 master->bits_per_word_mask = SPI_BPW_MASK(8); 73 master->max_speed_hz = OCTEON_SPI_MAX_CLOCK_HZ; 74 master->dev.of_node = pdev->dev.of_node; 75 76 pci_set_drvdata(pdev, master); 77 78 ret = devm_spi_register_master(dev, master); 79 if (ret) 80 goto error; 81 82 return 0; 83 84 error: 85 clk_disable_unprepare(p->clk); 86 pci_release_regions(pdev); 87 spi_master_put(master); 88 return ret; 89 } 90 91 static void thunderx_spi_remove(struct pci_dev *pdev) 92 { 93 struct spi_master *master = pci_get_drvdata(pdev); 94 struct octeon_spi *p; 95 96 p = spi_master_get_devdata(master); 97 if (!p) 98 return; 99 100 clk_disable_unprepare(p->clk); 101 pci_release_regions(pdev); 102 /* Put everything in a known state. */ 103 writeq(0, p->register_base + OCTEON_SPI_CFG(p)); 104 } 105 106 static const struct pci_device_id thunderx_spi_pci_id_table[] = { 107 { PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xa00b) }, 108 { 0, } 109 }; 110 111 MODULE_DEVICE_TABLE(pci, thunderx_spi_pci_id_table); 112 113 static struct pci_driver thunderx_spi_driver = { 114 .name = DRV_NAME, 115 .id_table = thunderx_spi_pci_id_table, 116 .probe = thunderx_spi_probe, 117 .remove = thunderx_spi_remove, 118 }; 119 120 module_pci_driver(thunderx_spi_driver); 121 122 MODULE_DESCRIPTION("Cavium, Inc. ThunderX SPI bus driver"); 123 MODULE_AUTHOR("Jan Glauber"); 124 MODULE_LICENSE("GPL"); 125