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 struct device *dev;
23 };
24
25 static const struct mfd_cell atmel_hlcdc_cells[] = {
26 {
27 .name = "atmel-hlcdc-pwm",
28 .of_compatible = "atmel,hlcdc-pwm",
29 },
30 {
31 .name = "atmel-hlcdc-dc",
32 .of_compatible = "atmel,hlcdc-display-controller",
33 },
34 };
35
regmap_atmel_hlcdc_reg_write(void * context,unsigned int reg,unsigned int val)36 static int regmap_atmel_hlcdc_reg_write(void *context, unsigned int reg,
37 unsigned int val)
38 {
39 struct atmel_hlcdc_regmap *hregmap = context;
40
41 if (reg <= ATMEL_HLCDC_DIS) {
42 u32 status;
43 int ret;
44
45 ret = readl_poll_timeout_atomic(hregmap->regs + ATMEL_HLCDC_SR,
46 status,
47 !(status & ATMEL_HLCDC_SIP),
48 1, 100);
49 if (ret) {
50 dev_err(hregmap->dev,
51 "Timeout! Clock domain synchronization is in progress!\n");
52 return ret;
53 }
54 }
55
56 writel(val, hregmap->regs + reg);
57
58 return 0;
59 }
60
regmap_atmel_hlcdc_reg_read(void * context,unsigned int reg,unsigned int * val)61 static int regmap_atmel_hlcdc_reg_read(void *context, unsigned int reg,
62 unsigned int *val)
63 {
64 struct atmel_hlcdc_regmap *hregmap = context;
65
66 *val = readl(hregmap->regs + reg);
67
68 return 0;
69 }
70
71 static const struct regmap_config atmel_hlcdc_regmap_config = {
72 .reg_bits = 32,
73 .val_bits = 32,
74 .reg_stride = 4,
75 .max_register = ATMEL_HLCDC_REG_MAX,
76 .reg_write = regmap_atmel_hlcdc_reg_write,
77 .reg_read = regmap_atmel_hlcdc_reg_read,
78 .fast_io = true,
79 };
80
atmel_hlcdc_probe(struct platform_device * pdev)81 static int atmel_hlcdc_probe(struct platform_device *pdev)
82 {
83 struct atmel_hlcdc_regmap *hregmap;
84 struct device *dev = &pdev->dev;
85 struct atmel_hlcdc *hlcdc;
86
87 hregmap = devm_kzalloc(dev, sizeof(*hregmap), GFP_KERNEL);
88 if (!hregmap)
89 return -ENOMEM;
90
91 hlcdc = devm_kzalloc(dev, sizeof(*hlcdc), GFP_KERNEL);
92 if (!hlcdc)
93 return -ENOMEM;
94
95 hregmap->regs = devm_platform_ioremap_resource(pdev, 0);
96 if (IS_ERR(hregmap->regs))
97 return PTR_ERR(hregmap->regs);
98
99 hregmap->dev = &pdev->dev;
100
101 hlcdc->irq = platform_get_irq(pdev, 0);
102 if (hlcdc->irq < 0)
103 return hlcdc->irq;
104
105 hlcdc->periph_clk = devm_clk_get(dev, "periph_clk");
106 if (IS_ERR(hlcdc->periph_clk)) {
107 dev_err(dev, "failed to get peripheral clock\n");
108 return PTR_ERR(hlcdc->periph_clk);
109 }
110
111 hlcdc->sys_clk = devm_clk_get(dev, "sys_clk");
112 if (IS_ERR(hlcdc->sys_clk)) {
113 dev_err(dev, "failed to get system clock\n");
114 return PTR_ERR(hlcdc->sys_clk);
115 }
116
117 hlcdc->slow_clk = devm_clk_get(dev, "slow_clk");
118 if (IS_ERR(hlcdc->slow_clk)) {
119 dev_err(dev, "failed to get slow clock\n");
120 return PTR_ERR(hlcdc->slow_clk);
121 }
122
123 hlcdc->regmap = devm_regmap_init(dev, NULL, hregmap,
124 &atmel_hlcdc_regmap_config);
125 if (IS_ERR(hlcdc->regmap))
126 return PTR_ERR(hlcdc->regmap);
127
128 dev_set_drvdata(dev, hlcdc);
129
130 return devm_mfd_add_devices(dev, -1, atmel_hlcdc_cells,
131 ARRAY_SIZE(atmel_hlcdc_cells),
132 NULL, 0, NULL);
133 }
134
135 static const struct of_device_id atmel_hlcdc_match[] = {
136 { .compatible = "atmel,at91sam9n12-hlcdc" },
137 { .compatible = "atmel,at91sam9x5-hlcdc" },
138 { .compatible = "atmel,sama5d2-hlcdc" },
139 { .compatible = "atmel,sama5d3-hlcdc" },
140 { .compatible = "atmel,sama5d4-hlcdc" },
141 { .compatible = "microchip,sam9x60-hlcdc" },
142 { .compatible = "microchip,sam9x75-xlcdc" },
143 { /* sentinel */ },
144 };
145 MODULE_DEVICE_TABLE(of, atmel_hlcdc_match);
146
147 static struct platform_driver atmel_hlcdc_driver = {
148 .probe = atmel_hlcdc_probe,
149 .driver = {
150 .name = "atmel-hlcdc",
151 .of_match_table = atmel_hlcdc_match,
152 },
153 };
154 module_platform_driver(atmel_hlcdc_driver);
155
156 MODULE_ALIAS("platform:atmel-hlcdc");
157 MODULE_AUTHOR("Boris Brezillon <boris.brezillon@free-electrons.com>");
158 MODULE_DESCRIPTION("Atmel HLCDC driver");
159 MODULE_LICENSE("GPL v2");
160