spi-cavium-thunderx.c 2.7 KB

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