1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * Copyright (C) 2015 Broadcom
4  */
5 
6 #include <linux/clk.h>
7 #include <linux/clk-provider.h>
8 #include <linux/io.h>
9 #include <linux/module.h>
10 #include <linux/platform_device.h>
11 #include <dt-bindings/clock/bcm2835-aux.h>
12 
13 #define BCM2835_AUXIRQ		0x00
14 #define BCM2835_AUXENB		0x04
15 
16 static int bcm2835_aux_clk_probe(struct platform_device *pdev)
17 {
18 	struct device *dev = &pdev->dev;
19 	struct clk_hw_onecell_data *onecell;
20 	const char *parent;
21 	struct clk *parent_clk;
22 	struct resource *res;
23 	void __iomem *reg, *gate;
24 
25 	parent_clk = devm_clk_get(dev, NULL);
26 	if (IS_ERR(parent_clk))
27 		return PTR_ERR(parent_clk);
28 	parent = __clk_get_name(parent_clk);
29 
30 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
31 	reg = devm_ioremap_resource(dev, res);
32 	if (IS_ERR(reg))
33 		return PTR_ERR(reg);
34 
35 	onecell = devm_kmalloc(dev,
36 			       struct_size(onecell, hws,
37 					   BCM2835_AUX_CLOCK_COUNT),
38 			       GFP_KERNEL);
39 	if (!onecell)
40 		return -ENOMEM;
41 	onecell->num = BCM2835_AUX_CLOCK_COUNT;
42 
43 	gate = reg + BCM2835_AUXENB;
44 	onecell->hws[BCM2835_AUX_CLOCK_UART] =
45 		clk_hw_register_gate(dev, "aux_uart", parent, 0, gate, 0, 0, NULL);
46 
47 	onecell->hws[BCM2835_AUX_CLOCK_SPI1] =
48 		clk_hw_register_gate(dev, "aux_spi1", parent, 0, gate, 1, 0, NULL);
49 
50 	onecell->hws[BCM2835_AUX_CLOCK_SPI2] =
51 		clk_hw_register_gate(dev, "aux_spi2", parent, 0, gate, 2, 0, NULL);
52 
53 	return of_clk_add_hw_provider(pdev->dev.of_node, of_clk_hw_onecell_get,
54 				      onecell);
55 }
56 
57 static const struct of_device_id bcm2835_aux_clk_of_match[] = {
58 	{ .compatible = "brcm,bcm2835-aux", },
59 	{},
60 };
61 MODULE_DEVICE_TABLE(of, bcm2835_aux_clk_of_match);
62 
63 static struct platform_driver bcm2835_aux_clk_driver = {
64 	.driver = {
65 		.name = "bcm2835-aux-clk",
66 		.of_match_table = bcm2835_aux_clk_of_match,
67 	},
68 	.probe          = bcm2835_aux_clk_probe,
69 };
70 builtin_platform_driver(bcm2835_aux_clk_driver);
71 
72 MODULE_AUTHOR("Eric Anholt <eric@anholt.net>");
73 MODULE_DESCRIPTION("BCM2835 auxiliary peripheral clock driver");
74 MODULE_LICENSE("GPL");
75