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
fsl_flexspi_clk_probe(struct platform_device * pdev)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");
107