drivers/spi/spi-cavium-thunderx.c

   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_controller *host;
  24         struct octeon_spi *p;
  25         int ret;
  26
  27         host = spi_alloc_host(dev, sizeof(struct octeon_spi));
  28         if (!host)
  29                 return -ENOMEM;
  30
  31         p = spi_controller_get_devdata(host);
  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_enabled(dev, NULL);
  53         if (IS_ERR(p->clk)) {
  54                 ret = PTR_ERR(p->clk);
  55                 goto error;
  56         }
  57
  58         p->sys_freq = clk_get_rate(p->clk);
  59         if (!p->sys_freq)
  60                 p->sys_freq = SYS_FREQ_DEFAULT;
  61         dev_info(dev, "Set system clock to %u\n", p->sys_freq);
  62
  63         host->flags = SPI_CONTROLLER_HALF_DUPLEX;
  64         host->num_chipselect = 4;
  65         host->mode_bits = SPI_CPHA | SPI_CPOL | SPI_CS_HIGH |
  66                             SPI_LSB_FIRST | SPI_3WIRE;
  67         host->transfer_one_message = octeon_spi_transfer_one_message;
  68         host->bits_per_word_mask = SPI_BPW_MASK(8);
  69         host->max_speed_hz = OCTEON_SPI_MAX_CLOCK_HZ;
  70         host->dev.of_node = pdev->dev.of_node;
  71
  72         pci_set_drvdata(pdev, host);
  73
  74         ret = devm_spi_register_controller(dev, host);
  75         if (ret)
  76                 goto error;
  77
  78         return 0;
  79
  80 error:
  81         pci_release_regions(pdev);
  82         spi_controller_put(host);
  83         return ret;
  84 }
  85
  86 static void thunderx_spi_remove(struct pci_dev *pdev)
  87 {
  88         struct spi_controller *host = pci_get_drvdata(pdev);
  89         struct octeon_spi *p;
  90
  91         p = spi_controller_get_devdata(host);
  92         if (!p)
  93                 return;
  94
  95         pci_release_regions(pdev);
  96         /* Put everything in a known state. */
  97         writeq(0, p->register_base + OCTEON_SPI_CFG(p));
  98 }
  99
 100 static const struct pci_device_id thunderx_spi_pci_id_table[] = {
 101         { PCI_DEVICE(PCI_VENDOR_ID_CAVIUM, 0xa00b) },
 102         { 0, }
 103 };
 104
 105 MODULE_DEVICE_TABLE(pci, thunderx_spi_pci_id_table);
 106
 107 static struct pci_driver thunderx_spi_driver = {
 108         .name           = DRV_NAME,
 109         .id_table       = thunderx_spi_pci_id_table,
 110         .probe          = thunderx_spi_probe,
 111         .remove         = thunderx_spi_remove,
 112 };
 113
 114 module_pci_driver(thunderx_spi_driver);
 115
 116 MODULE_DESCRIPTION("Cavium, Inc. ThunderX SPI bus driver");
 117 MODULE_AUTHOR("Jan Glauber");
 118 MODULE_LICENSE("GPL");