xref: /openbmc/linux/drivers/soc/qcom/qcom_gsbi.c (revision e2c75e76)
1 /*
2  * Copyright (c) 2014, The Linux foundation. All rights reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License rev 2 and
6  * only rev 2 as published by the free Software foundation.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or fITNESS fOR A PARTICULAR PURPOSE.  See the
11  * GNU General Public License for more details.
12  */
13 
14 #include <linux/clk.h>
15 #include <linux/err.h>
16 #include <linux/io.h>
17 #include <linux/module.h>
18 #include <linux/of.h>
19 #include <linux/of_platform.h>
20 #include <linux/platform_device.h>
21 #include <linux/regmap.h>
22 #include <linux/mfd/syscon.h>
23 #include <dt-bindings/soc/qcom,gsbi.h>
24 
25 #define GSBI_CTRL_REG		0x0000
26 #define GSBI_PROTOCOL_SHIFT	4
27 #define MAX_GSBI		12
28 
29 #define TCSR_ADM_CRCI_BASE	0x70
30 
31 struct crci_config {
32 	u32 num_rows;
33 	const u32 (*array)[MAX_GSBI];
34 };
35 
36 static const u32 crci_ipq8064[][MAX_GSBI] = {
37 	{
38 		0x000003, 0x00000c, 0x000030, 0x0000c0,
39 		0x000300, 0x000c00, 0x003000, 0x00c000,
40 		0x030000, 0x0c0000, 0x300000, 0xc00000
41 	},
42 	{
43 		0x000003, 0x00000c, 0x000030, 0x0000c0,
44 		0x000300, 0x000c00, 0x003000, 0x00c000,
45 		0x030000, 0x0c0000, 0x300000, 0xc00000
46 	},
47 };
48 
49 static const struct crci_config config_ipq8064 = {
50 	.num_rows = ARRAY_SIZE(crci_ipq8064),
51 	.array = crci_ipq8064,
52 };
53 
54 static const unsigned int crci_apq8064[][MAX_GSBI] = {
55 	{
56 		0x001800, 0x006000, 0x000030, 0x0000c0,
57 		0x000300, 0x000400, 0x000000, 0x000000,
58 		0x000000, 0x000000, 0x000000, 0x000000
59 	},
60 	{
61 		0x000000, 0x000000, 0x000000, 0x000000,
62 		0x000000, 0x000020, 0x0000c0, 0x000000,
63 		0x000000, 0x000000, 0x000000, 0x000000
64 	},
65 };
66 
67 static const struct crci_config config_apq8064 = {
68 	.num_rows = ARRAY_SIZE(crci_apq8064),
69 	.array = crci_apq8064,
70 };
71 
72 static const unsigned int crci_msm8960[][MAX_GSBI] = {
73 	{
74 		0x000003, 0x00000c, 0x000030, 0x0000c0,
75 		0x000300, 0x000400, 0x000000, 0x000000,
76 		0x000000, 0x000000, 0x000000, 0x000000
77 	},
78 	{
79 		0x000000, 0x000000, 0x000000, 0x000000,
80 		0x000000, 0x000020, 0x0000c0, 0x000300,
81 		0x001800, 0x006000, 0x000000, 0x000000
82 	},
83 };
84 
85 static const struct crci_config config_msm8960 = {
86 	.num_rows = ARRAY_SIZE(crci_msm8960),
87 	.array = crci_msm8960,
88 };
89 
90 static const unsigned int crci_msm8660[][MAX_GSBI] = {
91 	{	/* ADM 0 - B */
92 		0x000003, 0x00000c, 0x000030, 0x0000c0,
93 		0x000300, 0x000c00, 0x003000, 0x00c000,
94 		0x030000, 0x0c0000, 0x300000, 0xc00000
95 	},
96 	{	/* ADM 0 - B */
97 		0x000003, 0x00000c, 0x000030, 0x0000c0,
98 		0x000300, 0x000c00, 0x003000, 0x00c000,
99 		0x030000, 0x0c0000, 0x300000, 0xc00000
100 	},
101 	{	/* ADM 1 - A */
102 		0x000003, 0x00000c, 0x000030, 0x0000c0,
103 		0x000300, 0x000c00, 0x003000, 0x00c000,
104 		0x030000, 0x0c0000, 0x300000, 0xc00000
105 	},
106 	{	/* ADM 1 - B */
107 		0x000003, 0x00000c, 0x000030, 0x0000c0,
108 		0x000300, 0x000c00, 0x003000, 0x00c000,
109 		0x030000, 0x0c0000, 0x300000, 0xc00000
110 	},
111 };
112 
113 static const struct crci_config config_msm8660 = {
114 	.num_rows = ARRAY_SIZE(crci_msm8660),
115 	.array = crci_msm8660,
116 };
117 
118 struct gsbi_info {
119 	struct clk *hclk;
120 	u32 mode;
121 	u32 crci;
122 	struct regmap *tcsr;
123 };
124 
125 static const struct of_device_id tcsr_dt_match[] = {
126 	{ .compatible = "qcom,tcsr-ipq8064", .data = &config_ipq8064},
127 	{ .compatible = "qcom,tcsr-apq8064", .data = &config_apq8064},
128 	{ .compatible = "qcom,tcsr-msm8960", .data = &config_msm8960},
129 	{ .compatible = "qcom,tcsr-msm8660", .data = &config_msm8660},
130 	{ },
131 };
132 
133 static int gsbi_probe(struct platform_device *pdev)
134 {
135 	struct device_node *node = pdev->dev.of_node;
136 	struct device_node *tcsr_node;
137 	const struct of_device_id *match;
138 	struct resource *res;
139 	void __iomem *base;
140 	struct gsbi_info *gsbi;
141 	int i;
142 	u32 mask, gsbi_num;
143 	const struct crci_config *config = NULL;
144 
145 	gsbi = devm_kzalloc(&pdev->dev, sizeof(*gsbi), GFP_KERNEL);
146 
147 	if (!gsbi)
148 		return -ENOMEM;
149 
150 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
151 	base = devm_ioremap_resource(&pdev->dev, res);
152 	if (IS_ERR(base))
153 		return PTR_ERR(base);
154 
155 	/* get the tcsr node and setup the config and regmap */
156 	gsbi->tcsr = syscon_regmap_lookup_by_phandle(node, "syscon-tcsr");
157 
158 	if (!IS_ERR(gsbi->tcsr)) {
159 		tcsr_node = of_parse_phandle(node, "syscon-tcsr", 0);
160 		if (tcsr_node) {
161 			match = of_match_node(tcsr_dt_match, tcsr_node);
162 			if (match)
163 				config = match->data;
164 			else
165 				dev_warn(&pdev->dev, "no matching TCSR\n");
166 
167 			of_node_put(tcsr_node);
168 		}
169 	}
170 
171 	if (of_property_read_u32(node, "cell-index", &gsbi_num)) {
172 		dev_err(&pdev->dev, "missing cell-index\n");
173 		return -EINVAL;
174 	}
175 
176 	if (gsbi_num < 1 || gsbi_num > MAX_GSBI) {
177 		dev_err(&pdev->dev, "invalid cell-index\n");
178 		return -EINVAL;
179 	}
180 
181 	if (of_property_read_u32(node, "qcom,mode", &gsbi->mode)) {
182 		dev_err(&pdev->dev, "missing mode configuration\n");
183 		return -EINVAL;
184 	}
185 
186 	/* not required, so default to 0 if not present */
187 	of_property_read_u32(node, "qcom,crci", &gsbi->crci);
188 
189 	dev_info(&pdev->dev, "GSBI port protocol: %d crci: %d\n",
190 		 gsbi->mode, gsbi->crci);
191 	gsbi->hclk = devm_clk_get(&pdev->dev, "iface");
192 	if (IS_ERR(gsbi->hclk))
193 		return PTR_ERR(gsbi->hclk);
194 
195 	clk_prepare_enable(gsbi->hclk);
196 
197 	writel_relaxed((gsbi->mode << GSBI_PROTOCOL_SHIFT) | gsbi->crci,
198 				base + GSBI_CTRL_REG);
199 
200 	/*
201 	 * modify tcsr to reflect mode and ADM CRCI mux
202 	 * Each gsbi contains a pair of bits, one for RX and one for TX
203 	 * SPI mode requires both bits cleared, otherwise they are set
204 	 */
205 	if (config) {
206 		for (i = 0; i < config->num_rows; i++) {
207 			mask = config->array[i][gsbi_num - 1];
208 
209 			if (gsbi->mode == GSBI_PROT_SPI)
210 				regmap_update_bits(gsbi->tcsr,
211 					TCSR_ADM_CRCI_BASE + 4 * i, mask, 0);
212 			else
213 				regmap_update_bits(gsbi->tcsr,
214 					TCSR_ADM_CRCI_BASE + 4 * i, mask, mask);
215 
216 		}
217 	}
218 
219 	/* make sure the gsbi control write is not reordered */
220 	wmb();
221 
222 	platform_set_drvdata(pdev, gsbi);
223 
224 	return of_platform_populate(node, NULL, NULL, &pdev->dev);
225 }
226 
227 static int gsbi_remove(struct platform_device *pdev)
228 {
229 	struct gsbi_info *gsbi = platform_get_drvdata(pdev);
230 
231 	clk_disable_unprepare(gsbi->hclk);
232 
233 	return 0;
234 }
235 
236 static const struct of_device_id gsbi_dt_match[] = {
237 	{ .compatible = "qcom,gsbi-v1.0.0", },
238 	{ },
239 };
240 
241 MODULE_DEVICE_TABLE(of, gsbi_dt_match);
242 
243 static struct platform_driver gsbi_driver = {
244 	.driver = {
245 		.name		= "gsbi",
246 		.of_match_table	= gsbi_dt_match,
247 	},
248 	.probe = gsbi_probe,
249 	.remove	= gsbi_remove,
250 };
251 
252 module_platform_driver(gsbi_driver);
253 
254 MODULE_AUTHOR("Andy Gross <agross@codeaurora.org>");
255 MODULE_DESCRIPTION("QCOM GSBI driver");
256 MODULE_LICENSE("GPL v2");
257