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/of_device.h>
20 #include <linux/platform_device.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 const struct of_device_id *of_id;
129 struct device *dev = &pdev->dev;
130 struct device_node *node = dev->of_node;
131 struct mxs_lradc *lradc;
132 struct mfd_cell *cells = NULL;
133 struct resource *res;
134 int ret = 0;
135 u32 ts_wires = 0;
136
137 lradc = devm_kzalloc(&pdev->dev, sizeof(*lradc), GFP_KERNEL);
138 if (!lradc)
139 return -ENOMEM;
140
141 of_id = of_match_device(mxs_lradc_dt_ids, &pdev->dev);
142 if (!of_id)
143 return -EINVAL;
144
145 lradc->soc = (enum mxs_lradc_id)of_id->data;
146
147 lradc->clk = devm_clk_get(&pdev->dev, NULL);
148 if (IS_ERR(lradc->clk)) {
149 dev_err(dev, "Failed to get the delay unit clock\n");
150 return PTR_ERR(lradc->clk);
151 }
152
153 ret = clk_prepare_enable(lradc->clk);
154 if (ret) {
155 dev_err(dev, "Failed to enable the delay unit clock\n");
156 return ret;
157 }
158
159 ret = of_property_read_u32(node, "fsl,lradc-touchscreen-wires",
160 &ts_wires);
161
162 if (!ret) {
163 lradc->buffer_vchans = BUFFER_VCHANS_LIMITED;
164
165 switch (ts_wires) {
166 case 4:
167 lradc->touchscreen_wire = MXS_LRADC_TOUCHSCREEN_4WIRE;
168 break;
169 case 5:
170 if (lradc->soc == IMX28_LRADC) {
171 lradc->touchscreen_wire =
172 MXS_LRADC_TOUCHSCREEN_5WIRE;
173 break;
174 }
175 /* fall through - to an error message for i.MX23 */
176 default:
177 dev_err(&pdev->dev,
178 "Unsupported number of touchscreen wires (%d)\n"
179 , ts_wires);
180 ret = -EINVAL;
181 goto err_clk;
182 }
183 } else {
184 lradc->buffer_vchans = BUFFER_VCHANS_ALL;
185 }
186
187 platform_set_drvdata(pdev, lradc);
188
189 res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
190 if (!res) {
191 ret = -ENOMEM;
192 goto err_clk;
193 }
194
195 switch (lradc->soc) {
196 case IMX23_LRADC:
197 mx23_adc_resources[RES_MEM] = *res;
198 mx23_touchscreen_resources[RES_MEM] = *res;
199 cells = mx23_cells;
200 break;
201 case IMX28_LRADC:
202 mx28_adc_resources[RES_MEM] = *res;
203 mx28_touchscreen_resources[RES_MEM] = *res;
204 cells = mx28_cells;
205 break;
206 default:
207 dev_err(dev, "Unsupported SoC\n");
208 ret = -ENODEV;
209 goto err_clk;
210 }
211
212 ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE,
213 &cells[ADC_CELL], 1, NULL, 0, NULL);
214 if (ret) {
215 dev_err(&pdev->dev, "Failed to add the ADC subdevice\n");
216 goto err_clk;
217 }
218
219 if (!lradc->touchscreen_wire)
220 return 0;
221
222 ret = devm_mfd_add_devices(&pdev->dev, PLATFORM_DEVID_NONE,
223 &cells[TSC_CELL], 1, NULL, 0, NULL);
224 if (ret) {
225 dev_err(&pdev->dev,
226 "Failed to add the touchscreen subdevice\n");
227 goto err_clk;
228 }
229
230 return 0;
231
232 err_clk:
233 clk_disable_unprepare(lradc->clk);
234
235 return ret;
236 }
237
mxs_lradc_remove(struct platform_device * pdev)238 static int mxs_lradc_remove(struct platform_device *pdev)
239 {
240 struct mxs_lradc *lradc = platform_get_drvdata(pdev);
241
242 clk_disable_unprepare(lradc->clk);
243
244 return 0;
245 }
246
247 static struct platform_driver mxs_lradc_driver = {
248 .driver = {
249 .name = "mxs-lradc",
250 .of_match_table = mxs_lradc_dt_ids,
251 },
252 .probe = mxs_lradc_probe,
253 .remove = mxs_lradc_remove,
254 };
255 module_platform_driver(mxs_lradc_driver);
256
257 MODULE_AUTHOR("Ksenija Stanojevic <ksenija.stanojevic@gmail.com>");
258 MODULE_DESCRIPTION("Freescale i.MX23/i.MX28 LRADC driver");
259 MODULE_LICENSE("GPL");
260 MODULE_ALIAS("platform:mxs-lradc");
261