1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * R-Car Generation 2 da9063(L)/da9210 regulator quirk |
4 | * |
5 | * Certain Gen2 development boards have an da9063 and one or more da9210 |
6 | * regulators. All of these regulators have their interrupt request lines |
7 | * tied to the same interrupt pin (IRQ2) on the SoC. |
8 | * |
9 | * After cold boot or da9063-induced restart, both the da9063 and da9210 seem |
10 | * to assert their interrupt request lines. Hence as soon as one driver |
11 | * requests this irq, it gets stuck in an interrupt storm, as it only manages |
12 | * to deassert its own interrupt request line, and the other driver hasn't |
13 | * installed an interrupt handler yet. |
14 | * |
15 | * To handle this, install a quirk that masks the interrupts in both the |
16 | * da9063 and da9210. This quirk has to run after the i2c master driver has |
17 | * been initialized, but before the i2c slave drivers are initialized. |
18 | * |
19 | * Copyright (C) 2015 Glider bvba |
20 | */ |
21 | |
22 | #include <linux/device.h> |
23 | #include <linux/i2c.h> |
24 | #include <linux/init.h> |
25 | #include <linux/io.h> |
26 | #include <linux/list.h> |
27 | #include <linux/notifier.h> |
28 | #include <linux/of.h> |
29 | #include <linux/of_irq.h> |
30 | #include <linux/mfd/da9063/registers.h> |
31 | |
32 | #define IRQC_BASE 0xe61c0000 |
33 | #define IRQC_MONITOR 0x104 /* IRQn Signal Level Monitor Register */ |
34 | |
35 | #define REGULATOR_IRQ_MASK BIT(2) /* IRQ2, active low */ |
36 | |
37 | /* start of DA9210 System Control and Event Registers */ |
38 | #define DA9210_REG_MASK_A 0x54 |
39 | |
40 | struct regulator_quirk { |
41 | struct list_head list; |
42 | const struct of_device_id *id; |
43 | struct device_node *np; |
44 | struct of_phandle_args irq_args; |
45 | struct i2c_msg i2c_msg; |
46 | bool shared; /* IRQ line is shared */ |
47 | }; |
48 | |
49 | static LIST_HEAD(quirk_list); |
50 | static void __iomem *irqc; |
51 | |
52 | /* first byte sets the memory pointer, following are consecutive reg values */ |
53 | static u8 da9063_irq_clr[] = { DA9063_REG_IRQ_MASK_A, 0xff, 0xff, 0xff, 0xff }; |
54 | static u8 da9210_irq_clr[] = { DA9210_REG_MASK_A, 0xff, 0xff }; |
55 | |
56 | static struct i2c_msg da9063_msg = { |
57 | .len = ARRAY_SIZE(da9063_irq_clr), |
58 | .buf = da9063_irq_clr, |
59 | }; |
60 | |
61 | static struct i2c_msg da9210_msg = { |
62 | .len = ARRAY_SIZE(da9210_irq_clr), |
63 | .buf = da9210_irq_clr, |
64 | }; |
65 | |
66 | static const struct of_device_id rcar_gen2_quirk_match[] = { |
67 | { .compatible = "dlg,da9063" , .data = &da9063_msg }, |
68 | { .compatible = "dlg,da9063l" , .data = &da9063_msg }, |
69 | { .compatible = "dlg,da9210" , .data = &da9210_msg }, |
70 | { /* sentinel */ } |
71 | }; |
72 | |
73 | static int regulator_quirk_notify(struct notifier_block *nb, |
74 | unsigned long action, void *data) |
75 | { |
76 | struct regulator_quirk *pos, *tmp; |
77 | struct device *dev = data; |
78 | struct i2c_client *client; |
79 | static bool done; |
80 | int ret; |
81 | u32 mon; |
82 | |
83 | if (done) |
84 | return 0; |
85 | |
86 | mon = ioread32(irqc + IRQC_MONITOR); |
87 | dev_dbg(dev, "%s: %ld, IRQC_MONITOR = 0x%x\n" , __func__, action, mon); |
88 | if (mon & REGULATOR_IRQ_MASK) |
89 | goto remove; |
90 | |
91 | if (action != BUS_NOTIFY_ADD_DEVICE || dev->type == &i2c_adapter_type) |
92 | return 0; |
93 | |
94 | client = to_i2c_client(dev); |
95 | dev_dbg(dev, "Detected %s\n" , client->name); |
96 | |
97 | /* |
98 | * Send message to all PMICs that share an IRQ line to deassert it. |
99 | * |
100 | * WARNING: This works only if all the PMICs are on the same I2C bus. |
101 | */ |
102 | list_for_each_entry(pos, &quirk_list, list) { |
103 | if (!pos->shared) |
104 | continue; |
105 | |
106 | if (pos->np->parent != client->dev.parent->of_node) |
107 | continue; |
108 | |
109 | dev_info(&client->dev, "clearing %s@0x%02x interrupts\n" , |
110 | pos->id->compatible, pos->i2c_msg.addr); |
111 | |
112 | ret = i2c_transfer(adap: client->adapter, msgs: &pos->i2c_msg, num: 1); |
113 | if (ret != 1) |
114 | dev_err(&client->dev, "i2c error %d\n" , ret); |
115 | } |
116 | |
117 | mon = ioread32(irqc + IRQC_MONITOR); |
118 | if (mon & REGULATOR_IRQ_MASK) |
119 | goto remove; |
120 | |
121 | return 0; |
122 | |
123 | remove: |
124 | dev_info(dev, "IRQ2 is not asserted, removing quirk\n" ); |
125 | |
126 | list_for_each_entry_safe(pos, tmp, &quirk_list, list) { |
127 | list_del(entry: &pos->list); |
128 | of_node_put(node: pos->np); |
129 | kfree(objp: pos); |
130 | } |
131 | |
132 | done = true; |
133 | iounmap(addr: irqc); |
134 | return 0; |
135 | } |
136 | |
137 | static struct notifier_block regulator_quirk_nb = { |
138 | .notifier_call = regulator_quirk_notify |
139 | }; |
140 | |
141 | static int __init rcar_gen2_regulator_quirk(void) |
142 | { |
143 | struct regulator_quirk *quirk, *pos, *tmp; |
144 | struct of_phandle_args *argsa, *argsb; |
145 | const struct of_device_id *id; |
146 | struct device_node *np; |
147 | u32 mon, addr; |
148 | int ret; |
149 | |
150 | if (!of_machine_is_compatible(compat: "renesas,koelsch" ) && |
151 | !of_machine_is_compatible(compat: "renesas,lager" ) && |
152 | !of_machine_is_compatible(compat: "renesas,porter" ) && |
153 | !of_machine_is_compatible(compat: "renesas,stout" ) && |
154 | !of_machine_is_compatible(compat: "renesas,gose" )) |
155 | return -ENODEV; |
156 | |
157 | for_each_matching_node_and_match(np, rcar_gen2_quirk_match, &id) { |
158 | if (!of_device_is_available(device: np)) { |
159 | of_node_put(node: np); |
160 | break; |
161 | } |
162 | |
163 | ret = of_property_read_u32(np, propname: "reg" , out_value: &addr); |
164 | if (ret) /* Skip invalid entry and continue */ |
165 | continue; |
166 | |
167 | quirk = kzalloc(size: sizeof(*quirk), GFP_KERNEL); |
168 | if (!quirk) { |
169 | ret = -ENOMEM; |
170 | of_node_put(node: np); |
171 | goto err_mem; |
172 | } |
173 | |
174 | argsa = &quirk->irq_args; |
175 | memcpy(&quirk->i2c_msg, id->data, sizeof(quirk->i2c_msg)); |
176 | |
177 | quirk->id = id; |
178 | quirk->np = of_node_get(node: np); |
179 | quirk->i2c_msg.addr = addr; |
180 | |
181 | ret = of_irq_parse_one(device: np, index: 0, out_irq: argsa); |
182 | if (ret) { /* Skip invalid entry and continue */ |
183 | of_node_put(node: np); |
184 | kfree(objp: quirk); |
185 | continue; |
186 | } |
187 | |
188 | list_for_each_entry(pos, &quirk_list, list) { |
189 | argsb = &pos->irq_args; |
190 | |
191 | if (argsa->args_count != argsb->args_count) |
192 | continue; |
193 | |
194 | ret = memcmp(p: argsa->args, q: argsb->args, |
195 | size: argsa->args_count * |
196 | sizeof(argsa->args[0])); |
197 | if (!ret) { |
198 | pos->shared = true; |
199 | quirk->shared = true; |
200 | } |
201 | } |
202 | |
203 | list_add_tail(new: &quirk->list, head: &quirk_list); |
204 | } |
205 | |
206 | irqc = ioremap(IRQC_BASE, PAGE_SIZE); |
207 | if (!irqc) { |
208 | ret = -ENOMEM; |
209 | goto err_mem; |
210 | } |
211 | |
212 | mon = ioread32(irqc + IRQC_MONITOR); |
213 | if (mon & REGULATOR_IRQ_MASK) { |
214 | pr_debug("%s: IRQ2 is not asserted, not installing quirk\n" , |
215 | __func__); |
216 | ret = 0; |
217 | goto err_free; |
218 | } |
219 | |
220 | pr_info("IRQ2 is asserted, installing regulator quirk\n" ); |
221 | |
222 | bus_register_notifier(bus: &i2c_bus_type, nb: ®ulator_quirk_nb); |
223 | return 0; |
224 | |
225 | err_free: |
226 | iounmap(addr: irqc); |
227 | err_mem: |
228 | list_for_each_entry_safe(pos, tmp, &quirk_list, list) { |
229 | list_del(entry: &pos->list); |
230 | of_node_put(node: pos->np); |
231 | kfree(objp: pos); |
232 | } |
233 | |
234 | return ret; |
235 | } |
236 | |
237 | arch_initcall(rcar_gen2_regulator_quirk); |
238 | |