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