drivers/clk/clk-fsl-flexspi.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Layerscape FlexSPI clock driver
   4  *
   5  * Copyright 2020 Michael Walle <michael@walle.cc>
   6  */
   7
   8 #include <linux/clk-provider.h>
   9 #include <linux/io.h>
  10 #include <linux/module.h>
  11 #include <linux/platform_device.h>
  12
  13 static const struct clk_div_table ls1028a_flexspi_divs[] = {
  14         { .val = 0, .div = 1, },
  15         { .val = 1, .div = 2, },
  16         { .val = 2, .div = 3, },
  17         { .val = 3, .div = 4, },
  18         { .val = 4, .div = 5, },
  19         { .val = 5, .div = 6, },
  20         { .val = 6, .div = 7, },
  21         { .val = 7, .div = 8, },
  22         { .val = 11, .div = 12, },
  23         { .val = 15, .div = 16, },
  24         { .val = 16, .div = 20, },
  25         { .val = 17, .div = 24, },
  26         { .val = 18, .div = 28, },
  27         { .val = 19, .div = 32, },
  28         { .val = 20, .div = 80, },
  29         {}
  30 };
  31
  32 static const struct clk_div_table lx2160a_flexspi_divs[] = {
  33         { .val = 1, .div = 2, },
  34         { .val = 3, .div = 4, },
  35         { .val = 5, .div = 6, },
  36         { .val = 7, .div = 8, },
  37         { .val = 11, .div = 12, },
  38         { .val = 15, .div = 16, },
  39         { .val = 16, .div = 20, },
  40         { .val = 17, .div = 24, },
  41         { .val = 18, .div = 28, },
  42         { .val = 19, .div = 32, },
  43         { .val = 20, .div = 80, },
  44         {}
  45 };
  46
  47 static int fsl_flexspi_clk_probe(struct platform_device *pdev)
  48 {
  49         struct device *dev = &pdev->dev;
  50         struct device_node *np = dev->of_node;
  51         const char *clk_name = np->name;
  52         const char *clk_parent;
  53         struct resource *res;
  54         void __iomem *reg;
  55         struct clk_hw *hw;
  56         const struct clk_div_table *divs;
  57
  58         divs = device_get_match_data(dev);
  59         if (!divs)
  60                 return -ENOENT;
  61
  62         res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
  63         if (!res)
  64                 return -ENOENT;
  65
  66         /*
  67          * Can't use devm_ioremap_resource() or devm_of_iomap() because the
  68          * resource might already be taken by the parent device.
  69          */
  70         reg = devm_ioremap(dev, res->start, resource_size(res));
  71         if (!reg)
  72                 return -ENOMEM;
  73
  74         clk_parent = of_clk_get_parent_name(np, 0);
  75         if (!clk_parent)
  76                 return -EINVAL;
  77
  78         of_property_read_string(np, "clock-output-names", &clk_name);
  79
  80         hw = devm_clk_hw_register_divider_table(dev, clk_name, clk_parent, 0,
  81                                                 reg, 0, 5, 0, divs, NULL);
  82         if (IS_ERR(hw))
  83                 return PTR_ERR(hw);
  84
  85         return devm_of_clk_add_hw_provider(dev, of_clk_hw_simple_get, hw);
  86 }
  87
  88 static const struct of_device_id fsl_flexspi_clk_dt_ids[] = {
  89         { .compatible = "fsl,ls1028a-flexspi-clk", .data = &ls1028a_flexspi_divs },
  90         { .compatible = "fsl,lx2160a-flexspi-clk", .data = &lx2160a_flexspi_divs },
  91         {}
  92 };
  93 MODULE_DEVICE_TABLE(of, fsl_flexspi_clk_dt_ids);
  94
  95 static struct platform_driver fsl_flexspi_clk_driver = {
  96         .driver = {
  97                 .name = "fsl-flexspi-clk",
  98                 .of_match_table = fsl_flexspi_clk_dt_ids,
  99         },
 100         .probe = fsl_flexspi_clk_probe,
 101 };
 102 module_platform_driver(fsl_flexspi_clk_driver);
 103
 104 MODULE_DESCRIPTION("FlexSPI clock driver for Layerscape SoCs");
 105 MODULE_AUTHOR("Michael Walle <michael@walle.cc>");
 106 MODULE_LICENSE("GPL");