xref: /openbmc/linux/drivers/mfd/atmel-hlcdc.c (revision b593bce5)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3  * Copyright (C) 2014 Free Electrons
4  * Copyright (C) 2014 Atmel
5  *
6  * Author: Boris BREZILLON <boris.brezillon@free-electrons.com>
7  */
8 
9 #include <linux/clk.h>
10 #include <linux/iopoll.h>
11 #include <linux/mfd/atmel-hlcdc.h>
12 #include <linux/mfd/core.h>
13 #include <linux/module.h>
14 #include <linux/mod_devicetable.h>
15 #include <linux/platform_device.h>
16 #include <linux/regmap.h>
17 
18 #define ATMEL_HLCDC_REG_MAX		(0x4000 - 0x4)
19 
20 struct atmel_hlcdc_regmap {
21 	void __iomem *regs;
22 };
23 
24 static const struct mfd_cell atmel_hlcdc_cells[] = {
25 	{
26 		.name = "atmel-hlcdc-pwm",
27 		.of_compatible = "atmel,hlcdc-pwm",
28 	},
29 	{
30 		.name = "atmel-hlcdc-dc",
31 		.of_compatible = "atmel,hlcdc-display-controller",
32 	},
33 };
34 
35 static int regmap_atmel_hlcdc_reg_write(void *context, unsigned int reg,
36 					unsigned int val)
37 {
38 	struct atmel_hlcdc_regmap *hregmap = context;
39 
40 	if (reg <= ATMEL_HLCDC_DIS) {
41 		u32 status;
42 
43 		readl_poll_timeout_atomic(hregmap->regs + ATMEL_HLCDC_SR,
44 					  status, !(status & ATMEL_HLCDC_SIP),
45 					  1, 100);
46 	}
47 
48 	writel(val, hregmap->regs + reg);
49 
50 	return 0;
51 }
52 
53 static int regmap_atmel_hlcdc_reg_read(void *context, unsigned int reg,
54 				       unsigned int *val)
55 {
56 	struct atmel_hlcdc_regmap *hregmap = context;
57 
58 	*val = readl(hregmap->regs + reg);
59 
60 	return 0;
61 }
62 
63 static const struct regmap_config atmel_hlcdc_regmap_config = {
64 	.reg_bits = 32,
65 	.val_bits = 32,
66 	.reg_stride = 4,
67 	.max_register = ATMEL_HLCDC_REG_MAX,
68 	.reg_write = regmap_atmel_hlcdc_reg_write,
69 	.reg_read = regmap_atmel_hlcdc_reg_read,
70 	.fast_io = true,
71 };
72 
73 static int atmel_hlcdc_probe(struct platform_device *pdev)
74 {
75 	struct atmel_hlcdc_regmap *hregmap;
76 	struct device *dev = &pdev->dev;
77 	struct atmel_hlcdc *hlcdc;
78 	struct resource *res;
79 
80 	hregmap = devm_kzalloc(dev, sizeof(*hregmap), GFP_KERNEL);
81 	if (!hregmap)
82 		return -ENOMEM;
83 
84 	hlcdc = devm_kzalloc(dev, sizeof(*hlcdc), GFP_KERNEL);
85 	if (!hlcdc)
86 		return -ENOMEM;
87 
88 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
89 	hregmap->regs = devm_ioremap_resource(dev, res);
90 	if (IS_ERR(hregmap->regs))
91 		return PTR_ERR(hregmap->regs);
92 
93 	hlcdc->irq = platform_get_irq(pdev, 0);
94 	if (hlcdc->irq < 0)
95 		return hlcdc->irq;
96 
97 	hlcdc->periph_clk = devm_clk_get(dev, "periph_clk");
98 	if (IS_ERR(hlcdc->periph_clk)) {
99 		dev_err(dev, "failed to get peripheral clock\n");
100 		return PTR_ERR(hlcdc->periph_clk);
101 	}
102 
103 	hlcdc->sys_clk = devm_clk_get(dev, "sys_clk");
104 	if (IS_ERR(hlcdc->sys_clk)) {
105 		dev_err(dev, "failed to get system clock\n");
106 		return PTR_ERR(hlcdc->sys_clk);
107 	}
108 
109 	hlcdc->slow_clk = devm_clk_get(dev, "slow_clk");
110 	if (IS_ERR(hlcdc->slow_clk)) {
111 		dev_err(dev, "failed to get slow clock\n");
112 		return PTR_ERR(hlcdc->slow_clk);
113 	}
114 
115 	hlcdc->regmap = devm_regmap_init(dev, NULL, hregmap,
116 					 &atmel_hlcdc_regmap_config);
117 	if (IS_ERR(hlcdc->regmap))
118 		return PTR_ERR(hlcdc->regmap);
119 
120 	dev_set_drvdata(dev, hlcdc);
121 
122 	return devm_mfd_add_devices(dev, -1, atmel_hlcdc_cells,
123 				    ARRAY_SIZE(atmel_hlcdc_cells),
124 				    NULL, 0, NULL);
125 }
126 
127 static const struct of_device_id atmel_hlcdc_match[] = {
128 	{ .compatible = "atmel,at91sam9n12-hlcdc" },
129 	{ .compatible = "atmel,at91sam9x5-hlcdc" },
130 	{ .compatible = "atmel,sama5d2-hlcdc" },
131 	{ .compatible = "atmel,sama5d3-hlcdc" },
132 	{ .compatible = "atmel,sama5d4-hlcdc" },
133 	{ .compatible = "microchip,sam9x60-hlcdc" },
134 	{ /* sentinel */ },
135 };
136 MODULE_DEVICE_TABLE(of, atmel_hlcdc_match);
137 
138 static struct platform_driver atmel_hlcdc_driver = {
139 	.probe = atmel_hlcdc_probe,
140 	.driver = {
141 		.name = "atmel-hlcdc",
142 		.of_match_table = atmel_hlcdc_match,
143 	},
144 };
145 module_platform_driver(atmel_hlcdc_driver);
146 
147 MODULE_ALIAS("platform:atmel-hlcdc");
148 MODULE_AUTHOR("Boris Brezillon <boris.brezillon@free-electrons.com>");
149 MODULE_DESCRIPTION("Atmel HLCDC driver");
150 MODULE_LICENSE("GPL v2");
151