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");