xref: /linux/drivers/mfd/mxs-lradc.c (revision a1ff5a7d78a036d6c2178ee5acd6ba4946243800)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Freescale MXS Low Resolution Analog-to-Digital Converter driver
4  *
5  * Copyright (c) 2012 DENX Software Engineering, GmbH.
6  * Copyright (c) 2017 Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
7  *
8  * Authors:
9  *  Marek Vasut <marex@denx.de>
10  *  Ksenija Stanojevic <ksenija.stanojevic@gmail.com>
11  */
12 
13 #include <linux/clk.h>
14 #include <linux/device.h>
15 #include <linux/mfd/core.h>
16 #include <linux/mfd/mxs-lradc.h>
17 #include <linux/module.h>
18 #include <linux/of.h>
19 #include <linux/platform_device.h>
20 #include <linux/property.h>
21 #include <linux/slab.h>
22 
23 #define ADC_CELL		0
24 #define TSC_CELL		1
25 #define RES_MEM			0
26 
27 enum mx23_lradc_irqs {
28 	MX23_LRADC_TS_IRQ = 0,
29 	MX23_LRADC_CH0_IRQ,
30 	MX23_LRADC_CH1_IRQ,
31 	MX23_LRADC_CH2_IRQ,
32 	MX23_LRADC_CH3_IRQ,
33 	MX23_LRADC_CH4_IRQ,
34 	MX23_LRADC_CH5_IRQ,
35 	MX23_LRADC_CH6_IRQ,
36 	MX23_LRADC_CH7_IRQ,
37 };
38 
39 enum mx28_lradc_irqs {
40 	MX28_LRADC_TS_IRQ = 0,
41 	MX28_LRADC_TRESH0_IRQ,
42 	MX28_LRADC_TRESH1_IRQ,
43 	MX28_LRADC_CH0_IRQ,
44 	MX28_LRADC_CH1_IRQ,
45 	MX28_LRADC_CH2_IRQ,
46 	MX28_LRADC_CH3_IRQ,
47 	MX28_LRADC_CH4_IRQ,
48 	MX28_LRADC_CH5_IRQ,
49 	MX28_LRADC_CH6_IRQ,
50 	MX28_LRADC_CH7_IRQ,
51 	MX28_LRADC_BUTTON0_IRQ,
52 	MX28_LRADC_BUTTON1_IRQ,
53 };
54 
55 static struct resource mx23_adc_resources[] = {
56 	DEFINE_RES_MEM(0x0, 0x0),
57 	DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH0_IRQ, "mxs-lradc-channel0"),
58 	DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH1_IRQ, "mxs-lradc-channel1"),
59 	DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH2_IRQ, "mxs-lradc-channel2"),
60 	DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH3_IRQ, "mxs-lradc-channel3"),
61 	DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH4_IRQ, "mxs-lradc-channel4"),
62 	DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH5_IRQ, "mxs-lradc-channel5"),
63 };
64 
65 static struct resource mx23_touchscreen_resources[] = {
66 	DEFINE_RES_MEM(0x0, 0x0),
67 	DEFINE_RES_IRQ_NAMED(MX23_LRADC_TS_IRQ, "mxs-lradc-touchscreen"),
68 	DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH6_IRQ, "mxs-lradc-channel6"),
69 	DEFINE_RES_IRQ_NAMED(MX23_LRADC_CH7_IRQ, "mxs-lradc-channel7"),
70 };
71 
72 static struct resource mx28_adc_resources[] = {
73 	DEFINE_RES_MEM(0x0, 0x0),
74 	DEFINE_RES_IRQ_NAMED(MX28_LRADC_TRESH0_IRQ, "mxs-lradc-thresh0"),
75 	DEFINE_RES_IRQ_NAMED(MX28_LRADC_TRESH1_IRQ, "mxs-lradc-thresh1"),
76 	DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH0_IRQ, "mxs-lradc-channel0"),
77 	DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH1_IRQ, "mxs-lradc-channel1"),
78 	DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH2_IRQ, "mxs-lradc-channel2"),
79 	DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH3_IRQ, "mxs-lradc-channel3"),
80 	DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH4_IRQ, "mxs-lradc-channel4"),
81 	DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH5_IRQ, "mxs-lradc-channel5"),
82 	DEFINE_RES_IRQ_NAMED(MX28_LRADC_BUTTON0_IRQ, "mxs-lradc-button0"),
83 	DEFINE_RES_IRQ_NAMED(MX28_LRADC_BUTTON1_IRQ, "mxs-lradc-button1"),
84 };
85 
86 static struct resource mx28_touchscreen_resources[] = {
87 	DEFINE_RES_MEM(0x0, 0x0),
88 	DEFINE_RES_IRQ_NAMED(MX28_LRADC_TS_IRQ, "mxs-lradc-touchscreen"),
89 	DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH6_IRQ, "mxs-lradc-channel6"),
90 	DEFINE_RES_IRQ_NAMED(MX28_LRADC_CH7_IRQ, "mxs-lradc-channel7"),
91 };
92 
93 static struct mfd_cell mx23_cells[] = {
94 	{
95 		.name = "mxs-lradc-adc",
96 		.resources = mx23_adc_resources,
97 		.num_resources = ARRAY_SIZE(mx23_adc_resources),
98 	},
99 	{
100 		.name = "mxs-lradc-ts",
101 		.resources = mx23_touchscreen_resources,
102 		.num_resources = ARRAY_SIZE(mx23_touchscreen_resources),
103 	},
104 };
105 
106 static struct mfd_cell mx28_cells[] = {
107 	{
108 		.name = "mxs-lradc-adc",
109 		.resources = mx28_adc_resources,
110 		.num_resources = ARRAY_SIZE(mx28_adc_resources),
111 	},
112 	{
113 		.name = "mxs-lradc-ts",
114 		.resources = mx28_touchscreen_resources,
115 		.num_resources = ARRAY_SIZE(mx28_touchscreen_resources),
116 	}
117 };
118 
119 static const struct of_device_id mxs_lradc_dt_ids[] = {
120 	{ .compatible = "fsl,imx23-lradc", .data = (void *)IMX23_LRADC, },
121 	{ .compatible = "fsl,imx28-lradc", .data = (void *)IMX28_LRADC, },
122 	{ /* sentinel */ }
123 };
124 MODULE_DEVICE_TABLE(of, mxs_lradc_dt_ids);
125 
mxs_lradc_probe(struct platform_device * pdev)126 static int mxs_lradc_probe(struct platform_device *pdev)
127 {
128 	struct device *dev = &pdev->dev;
129 	struct device_node *node = dev->of_node;
130 	struct mxs_lradc *lradc;
131 	struct mfd_cell *cells = NULL;
132 	struct resource *res;
133 	int ret = 0;
134 	u32 ts_wires = 0;
135 
136 	lradc = devm_kzalloc(&pdev->dev, sizeof(*lradc), GFP_KERNEL);
137 	if (!lradc)
138 		return -ENOMEM;
139 
140 	lradc->soc = (kernel_ulong_t)device_get_match_data(&pdev->dev);
141 
142 	lradc->clk = devm_clk_get(&pdev->dev, NULL);
143 	if (IS_ERR(lradc->clk)) {
144 		dev_err(dev, "Failed to get the delay unit clock\n");
145 		return PTR_ERR(lradc->clk);
146 	}
147 
148 	ret = clk_prepare_enable(lradc->clk);
149 	if (ret) {
150 		dev_err(dev, "Failed to enable the delay unit clock\n");
151 		return ret;
152 	}
153 
154 	ret = of_property_read_u32(node, "fsl,lradc-touchscreen-wires",
155 					 &ts_wires);
156 
157 	if (!ret) {
158 		lradc->buffer_vchans = BUFFER_VCHANS_LIMITED;
159 
160 		switch (ts_wires) {
161 		case 4:
162 			lradc->touchscreen_wire = MXS_LRADC_TOUCHSCREEN_4WIRE;
163 			break;
164 		case 5:
165 			if (lradc->soc == IMX28_LRADC) {
166 				lradc->touchscreen_wire =
167 					MXS_LRADC_TOUCHSCREEN_5WIRE;
168 				break;
169 			}
170 			fallthrough;	/* to an error message for i.MX23 */
171 		default:
172 			dev_err(&pdev->dev,
173 				"Unsupported number of touchscreen wires (%d)\n"
174 				, ts_wires);
175 			ret = -EINVAL;
176 			goto err_clk;
177 		}
178 	} else {
179 		lradc->buffer_vchans = BUFFER_VCHANS_ALL;
180 	}
181 
182 	platform_set_drvdata(pdev, lradc);
183 
184 	res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
185 	if (!res) {
186 		ret = -ENOMEM;
187 		goto err_clk;
188 	}
189 
190 	switch (lradc->soc) {
191 	case IMX23_LRADC:
192 		mx23_adc_resources[RES_MEM] = *res;
193 		mx23_touchscreen_resources[RES_MEM] = *res;
194 		cells = mx23_cells;
195 		break;
196 	case IMX28_LRADC:
197 		mx28_adc_resources[RES_MEM] = *res;
198 		mx28_touchscreen_resources[RES_MEM] = *res;
199 		cells = mx28_cells;
200 		break;
201 	default:
202 		dev_err(dev, "Unsupported SoC\n");
203 		ret = -ENODEV;
204 		goto err_clk;
205 	}
206 
207 	ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE,
208 				   &cells[ADC_CELL], 1, NULL, 0, NULL);
209 	if (ret) {
210 		dev_err(&pdev->dev, "Failed to add the ADC subdevice\n");
211 		goto err_clk;
212 	}
213 
214 	if (!lradc->touchscreen_wire)
215 		return 0;
216 
217 	ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE,
218 				   &cells[TSC_CELL], 1, NULL, 0, NULL);
219 	if (ret) {
220 		dev_err(&pdev->dev,
221 			"Failed to add the touchscreen subdevice\n");
222 		goto err_clk;
223 	}
224 
225 	return 0;
226 
227 err_clk:
228 	clk_disable_unprepare(lradc->clk);
229 
230 	return ret;
231 }
232 
mxs_lradc_remove(struct platform_device * pdev)233 static void mxs_lradc_remove(struct platform_device *pdev)
234 {
235 	struct mxs_lradc *lradc = platform_get_drvdata(pdev);
236 
237 	clk_disable_unprepare(lradc->clk);
238 }
239 
240 static struct platform_driver mxs_lradc_driver = {
241 	.driver = {
242 		.name = "mxs-lradc",
243 		.of_match_table = mxs_lradc_dt_ids,
244 	},
245 	.probe = mxs_lradc_probe,
246 	.remove_new = mxs_lradc_remove,
247 };
248 module_platform_driver(mxs_lradc_driver);
249 
250 MODULE_AUTHOR("Ksenija Stanojevic <ksenija.stanojevic@gmail.com>");
251 MODULE_DESCRIPTION("Freescale i.MX23/i.MX28 LRADC driver");
252 MODULE_LICENSE("GPL");
253 MODULE_ALIAS("platform:mxs-lradc");
254