1 // SPDX-License-Identifier: GPL-2.0
3 * R-Car Generation 2 da9063/da9210 regulator quirk
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.
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.
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.
19 * Copyright (C) 2015 Glider bvba
22 #include <linux/device.h>
23 #include <linux/i2c.h>
24 #include <linux/init.h>
26 #include <linux/list.h>
27 #include <linux/notifier.h>
29 #include <linux/of_irq.h>
30 #include <linux/mfd/da9063/registers.h>
32 #define IRQC_BASE 0xe61c0000
33 #define IRQC_MONITOR 0x104 /* IRQn Signal Level Monitor Register */
35 #define REGULATOR_IRQ_MASK BIT(2) /* IRQ2, active low */
37 /* start of DA9210 System Control and Event Registers */
38 #define DA9210_REG_MASK_A 0x54
40 struct regulator_quirk {
41 struct list_head list;
42 const struct of_device_id *id;
43 struct of_phandle_args irq_args;
44 struct i2c_msg i2c_msg;
45 bool shared; /* IRQ line is shared */
48 static LIST_HEAD(quirk_list);
49 static void __iomem *irqc;
51 /* first byte sets the memory pointer, following are consecutive reg values */
52 static u8 da9063_irq_clr[] = { DA9063_REG_IRQ_MASK_A, 0xff, 0xff, 0xff, 0xff };
53 static u8 da9210_irq_clr[] = { DA9210_REG_MASK_A, 0xff, 0xff };
55 static struct i2c_msg da9063_msg = {
56 .len = ARRAY_SIZE(da9063_irq_clr),
57 .buf = da9063_irq_clr,
60 static struct i2c_msg da9210_msg = {
61 .len = ARRAY_SIZE(da9210_irq_clr),
62 .buf = da9210_irq_clr,
65 static const struct of_device_id rcar_gen2_quirk_match[] = {
66 { .compatible = "dlg,da9063", .data = &da9063_msg },
67 { .compatible = "dlg,da9210", .data = &da9210_msg },
71 static int regulator_quirk_notify(struct notifier_block *nb,
72 unsigned long action, void *data)
74 struct regulator_quirk *pos, *tmp;
75 struct device *dev = data;
76 struct i2c_client *client;
84 mon = ioread32(irqc + IRQC_MONITOR);
85 dev_dbg(dev, "%s: %ld, IRQC_MONITOR = 0x%x\n", __func__, action, mon);
86 if (mon & REGULATOR_IRQ_MASK)
89 if (action != BUS_NOTIFY_ADD_DEVICE || dev->type == &i2c_adapter_type)
92 client = to_i2c_client(dev);
93 dev_dbg(dev, "Detected %s\n", client->name);
96 * Send message to all PMICs that share an IRQ line to deassert it.
98 * WARNING: This works only if all the PMICs are on the same I2C bus.
100 list_for_each_entry(pos, &quirk_list, list) {
104 dev_info(&client->dev, "clearing %s@0x%02x interrupts\n",
105 pos->id->compatible, pos->i2c_msg.addr);
107 ret = i2c_transfer(client->adapter, &pos->i2c_msg, 1);
109 dev_err(&client->dev, "i2c error %d\n", ret);
112 mon = ioread32(irqc + IRQC_MONITOR);
113 if (mon & REGULATOR_IRQ_MASK)
119 dev_info(dev, "IRQ2 is not asserted, removing quirk\n");
121 list_for_each_entry_safe(pos, tmp, &quirk_list, list) {
122 list_del(&pos->list);
131 static struct notifier_block regulator_quirk_nb = {
132 .notifier_call = regulator_quirk_notify
135 static int __init rcar_gen2_regulator_quirk(void)
137 struct regulator_quirk *quirk, *pos, *tmp;
138 struct of_phandle_args *argsa, *argsb;
139 const struct of_device_id *id;
140 struct device_node *np;
144 if (!of_machine_is_compatible("renesas,koelsch") &&
145 !of_machine_is_compatible("renesas,lager") &&
146 !of_machine_is_compatible("renesas,stout") &&
147 !of_machine_is_compatible("renesas,gose"))
150 for_each_matching_node_and_match(np, rcar_gen2_quirk_match, &id) {
151 if (!of_device_is_available(np))
154 ret = of_property_read_u32(np, "reg", &addr);
155 if (ret) /* Skip invalid entry and continue */
158 quirk = kzalloc(sizeof(*quirk), GFP_KERNEL);
164 argsa = &quirk->irq_args;
165 memcpy(&quirk->i2c_msg, id->data, sizeof(quirk->i2c_msg));
168 quirk->i2c_msg.addr = addr;
170 ret = of_irq_parse_one(np, 0, argsa);
171 if (ret) { /* Skip invalid entry and continue */
176 list_for_each_entry(pos, &quirk_list, list) {
177 argsb = &pos->irq_args;
179 if (argsa->args_count != argsb->args_count)
182 ret = memcmp(argsa->args, argsb->args,
184 sizeof(argsa->args[0]));
187 quirk->shared = true;
191 list_add_tail(&quirk->list, &quirk_list);
194 irqc = ioremap(IRQC_BASE, PAGE_SIZE);
200 mon = ioread32(irqc + IRQC_MONITOR);
201 if (mon & REGULATOR_IRQ_MASK) {
202 pr_debug("%s: IRQ2 is not asserted, not installing quirk\n",
208 pr_info("IRQ2 is asserted, installing da9063/da9210 regulator quirk\n");
210 bus_register_notifier(&i2c_bus_type, ®ulator_quirk_nb);
216 list_for_each_entry_safe(pos, tmp, &quirk_list, list) {
217 list_del(&pos->list);
224 arch_initcall(rcar_gen2_regulator_quirk);