1 | // SPDX-License-Identifier: GPL-2.0+ |
2 | // |
3 | // wm831x-isink.c -- Current sink driver for the WM831x series |
4 | // |
5 | // Copyright 2009 Wolfson Microelectronics PLC. |
6 | // |
7 | // Author: Mark Brown <broonie@opensource.wolfsonmicro.com> |
8 | |
9 | #include <linux/module.h> |
10 | #include <linux/moduleparam.h> |
11 | #include <linux/init.h> |
12 | #include <linux/bitops.h> |
13 | #include <linux/err.h> |
14 | #include <linux/i2c.h> |
15 | #include <linux/platform_device.h> |
16 | #include <linux/regulator/driver.h> |
17 | #include <linux/slab.h> |
18 | |
19 | #include <linux/mfd/wm831x/core.h> |
20 | #include <linux/mfd/wm831x/regulator.h> |
21 | #include <linux/mfd/wm831x/pdata.h> |
22 | |
23 | #define WM831X_ISINK_MAX_NAME 7 |
24 | |
25 | struct wm831x_isink { |
26 | char name[WM831X_ISINK_MAX_NAME]; |
27 | struct regulator_desc desc; |
28 | int reg; |
29 | struct wm831x *wm831x; |
30 | struct regulator_dev *regulator; |
31 | }; |
32 | |
33 | static int wm831x_isink_enable(struct regulator_dev *rdev) |
34 | { |
35 | struct wm831x_isink *isink = rdev_get_drvdata(rdev); |
36 | struct wm831x *wm831x = isink->wm831x; |
37 | int ret; |
38 | |
39 | /* We have a two stage enable: first start the ISINK... */ |
40 | ret = wm831x_set_bits(wm831x, reg: isink->reg, WM831X_CS1_ENA, |
41 | WM831X_CS1_ENA); |
42 | if (ret != 0) |
43 | return ret; |
44 | |
45 | /* ...then enable drive */ |
46 | ret = wm831x_set_bits(wm831x, reg: isink->reg, WM831X_CS1_DRIVE, |
47 | WM831X_CS1_DRIVE); |
48 | if (ret != 0) |
49 | wm831x_set_bits(wm831x, reg: isink->reg, WM831X_CS1_ENA, val: 0); |
50 | |
51 | return ret; |
52 | |
53 | } |
54 | |
55 | static int wm831x_isink_disable(struct regulator_dev *rdev) |
56 | { |
57 | struct wm831x_isink *isink = rdev_get_drvdata(rdev); |
58 | struct wm831x *wm831x = isink->wm831x; |
59 | int ret; |
60 | |
61 | ret = wm831x_set_bits(wm831x, reg: isink->reg, WM831X_CS1_DRIVE, val: 0); |
62 | if (ret < 0) |
63 | return ret; |
64 | |
65 | ret = wm831x_set_bits(wm831x, reg: isink->reg, WM831X_CS1_ENA, val: 0); |
66 | if (ret < 0) |
67 | return ret; |
68 | |
69 | return ret; |
70 | |
71 | } |
72 | |
73 | static int wm831x_isink_is_enabled(struct regulator_dev *rdev) |
74 | { |
75 | struct wm831x_isink *isink = rdev_get_drvdata(rdev); |
76 | struct wm831x *wm831x = isink->wm831x; |
77 | int ret; |
78 | |
79 | ret = wm831x_reg_read(wm831x, reg: isink->reg); |
80 | if (ret < 0) |
81 | return ret; |
82 | |
83 | if ((ret & (WM831X_CS1_ENA | WM831X_CS1_DRIVE)) == |
84 | (WM831X_CS1_ENA | WM831X_CS1_DRIVE)) |
85 | return 1; |
86 | else |
87 | return 0; |
88 | } |
89 | |
90 | static const struct regulator_ops wm831x_isink_ops = { |
91 | .is_enabled = wm831x_isink_is_enabled, |
92 | .enable = wm831x_isink_enable, |
93 | .disable = wm831x_isink_disable, |
94 | .set_current_limit = regulator_set_current_limit_regmap, |
95 | .get_current_limit = regulator_get_current_limit_regmap, |
96 | }; |
97 | |
98 | static irqreturn_t wm831x_isink_irq(int irq, void *data) |
99 | { |
100 | struct wm831x_isink *isink = data; |
101 | |
102 | regulator_notifier_call_chain(rdev: isink->regulator, |
103 | REGULATOR_EVENT_OVER_CURRENT, |
104 | NULL); |
105 | |
106 | return IRQ_HANDLED; |
107 | } |
108 | |
109 | |
110 | static int wm831x_isink_probe(struct platform_device *pdev) |
111 | { |
112 | struct wm831x *wm831x = dev_get_drvdata(dev: pdev->dev.parent); |
113 | struct wm831x_pdata *pdata = dev_get_platdata(dev: wm831x->dev); |
114 | struct wm831x_isink *isink; |
115 | int id = pdev->id % ARRAY_SIZE(pdata->isink); |
116 | struct regulator_config config = { }; |
117 | struct resource *res; |
118 | int ret, irq; |
119 | |
120 | dev_dbg(&pdev->dev, "Probing ISINK%d\n" , id + 1); |
121 | |
122 | if (pdata == NULL || pdata->isink[id] == NULL) |
123 | return -ENODEV; |
124 | |
125 | isink = devm_kzalloc(dev: &pdev->dev, size: sizeof(struct wm831x_isink), |
126 | GFP_KERNEL); |
127 | if (!isink) |
128 | return -ENOMEM; |
129 | |
130 | isink->wm831x = wm831x; |
131 | |
132 | res = platform_get_resource(pdev, IORESOURCE_REG, 0); |
133 | if (res == NULL) { |
134 | dev_err(&pdev->dev, "No REG resource\n" ); |
135 | ret = -EINVAL; |
136 | goto err; |
137 | } |
138 | isink->reg = res->start; |
139 | |
140 | /* For current parts this is correct; probably need to revisit |
141 | * in future. |
142 | */ |
143 | snprintf(buf: isink->name, size: sizeof(isink->name), fmt: "ISINK%d" , id + 1); |
144 | isink->desc.name = isink->name; |
145 | isink->desc.id = id; |
146 | isink->desc.ops = &wm831x_isink_ops; |
147 | isink->desc.type = REGULATOR_CURRENT; |
148 | isink->desc.owner = THIS_MODULE; |
149 | isink->desc.curr_table = wm831x_isinkv_values, |
150 | isink->desc.n_current_limits = ARRAY_SIZE(wm831x_isinkv_values), |
151 | isink->desc.csel_reg = isink->reg, |
152 | isink->desc.csel_mask = WM831X_CS1_ISEL_MASK, |
153 | |
154 | config.dev = pdev->dev.parent; |
155 | config.init_data = pdata->isink[id]; |
156 | config.driver_data = isink; |
157 | config.regmap = wm831x->regmap; |
158 | |
159 | isink->regulator = devm_regulator_register(dev: &pdev->dev, regulator_desc: &isink->desc, |
160 | config: &config); |
161 | if (IS_ERR(ptr: isink->regulator)) { |
162 | ret = PTR_ERR(ptr: isink->regulator); |
163 | dev_err(wm831x->dev, "Failed to register ISINK%d: %d\n" , |
164 | id + 1, ret); |
165 | goto err; |
166 | } |
167 | |
168 | irq = wm831x_irq(wm831x, irq: platform_get_irq(pdev, 0)); |
169 | ret = devm_request_threaded_irq(dev: &pdev->dev, irq, NULL, |
170 | thread_fn: wm831x_isink_irq, |
171 | IRQF_TRIGGER_RISING | IRQF_ONESHOT, |
172 | devname: isink->name, |
173 | dev_id: isink); |
174 | if (ret != 0) { |
175 | dev_err(&pdev->dev, "Failed to request ISINK IRQ %d: %d\n" , |
176 | irq, ret); |
177 | goto err; |
178 | } |
179 | |
180 | platform_set_drvdata(pdev, data: isink); |
181 | |
182 | return 0; |
183 | |
184 | err: |
185 | return ret; |
186 | } |
187 | |
188 | static struct platform_driver wm831x_isink_driver = { |
189 | .probe = wm831x_isink_probe, |
190 | .driver = { |
191 | .name = "wm831x-isink" , |
192 | .probe_type = PROBE_PREFER_ASYNCHRONOUS, |
193 | }, |
194 | }; |
195 | |
196 | static int __init wm831x_isink_init(void) |
197 | { |
198 | int ret; |
199 | ret = platform_driver_register(&wm831x_isink_driver); |
200 | if (ret != 0) |
201 | pr_err("Failed to register WM831x ISINK driver: %d\n" , ret); |
202 | |
203 | return ret; |
204 | } |
205 | subsys_initcall(wm831x_isink_init); |
206 | |
207 | static void __exit wm831x_isink_exit(void) |
208 | { |
209 | platform_driver_unregister(&wm831x_isink_driver); |
210 | } |
211 | module_exit(wm831x_isink_exit); |
212 | |
213 | /* Module information */ |
214 | MODULE_AUTHOR("Mark Brown" ); |
215 | MODULE_DESCRIPTION("WM831x current sink driver" ); |
216 | MODULE_LICENSE("GPL" ); |
217 | MODULE_ALIAS("platform:wm831x-isink" ); |
218 | |