LXR linux/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
  13static 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
  32static 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
  47static 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
  88static 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};
  93MODULE_DEVICE_TABLE(of, fsl_flexspi_clk_dt_ids);
  94
  95static 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};
 102module_platform_driver(fsl_flexspi_clk_driver);
 103
 104MODULE_DESCRIPTION("FlexSPI clock driver for Layerscape SoCs");
 105MODULE_AUTHOR("Michael Walle <michael@walle.cc>");
 106MODULE_LICENSE("GPL");
 107