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// SPDX-License-Identifier: GPL-2.0
/*
* R-Car Generation 2 da9063/da9210 regulator quirk
*
* Certain Gen2 development boards have an da9063 and one or more da9210
* regulators. All of these regulators have their interrupt request lines
* tied to the same interrupt pin (IRQ2) on the SoC.
*
* After cold boot or da9063-induced restart, both the da9063 and da9210 seem
* to assert their interrupt request lines. Hence as soon as one driver
* requests this irq, it gets stuck in an interrupt storm, as it only manages
* to deassert its own interrupt request line, and the other driver hasn't
* installed an interrupt handler yet.
*
* To handle this, install a quirk that masks the interrupts in both the
* da9063 and da9210. This quirk has to run after the i2c master driver has
* been initialized, but before the i2c slave drivers are initialized.
*
* Copyright (C) 2015 Glider bvba
*/
#include <linux/device.h>
#include <linux/i2c.h>
#include <linux/init.h>
#include <linux/io.h>
#include <linux/notifier.h>
#include <linux/of.h>
#include <linux/mfd/da9063/registers.h>
#define IRQC_BASE 0xe61c0000
#define IRQC_MONITOR 0x104 /* IRQn Signal Level Monitor Register */
#define REGULATOR_IRQ_MASK BIT(2) /* IRQ2, active low */
/* start of DA9210 System Control and Event Registers */
#define DA9210_REG_MASK_A 0x54
static void __iomem *irqc;
/* first byte sets the memory pointer, following are consecutive reg values */
static u8 da9063_irq_clr[] = { DA9063_REG_IRQ_MASK_A, 0xff, 0xff, 0xff, 0xff };
static u8 da9210_irq_clr[] = { DA9210_REG_MASK_A, 0xff, 0xff };
static struct i2c_msg da9xxx_msgs[3] = {
{
.addr = 0x58,
.len = ARRAY_SIZE(da9063_irq_clr),
.buf = da9063_irq_clr,
}, {
.addr = 0x68,
.len = ARRAY_SIZE(da9210_irq_clr),
.buf = da9210_irq_clr,
}, {
.addr = 0x70,
.len = ARRAY_SIZE(da9210_irq_clr),
.buf = da9210_irq_clr,
},
};
static int regulator_quirk_notify(struct notifier_block *nb,
unsigned long action, void *data)
{
struct device *dev = data;
struct i2c_client *client;
static bool done;
u32 mon;
if (done)
return 0;
mon = ioread32(irqc + IRQC_MONITOR);
dev_dbg(dev, "%s: %ld, IRQC_MONITOR = 0x%x\n", __func__, action, mon);
if (mon & REGULATOR_IRQ_MASK)
goto remove;
if (action != BUS_NOTIFY_ADD_DEVICE || dev->type == &i2c_adapter_type)
return 0;
client = to_i2c_client(dev);
dev_dbg(dev, "Detected %s\n", client->name);
if ((client->addr == 0x58 && !strcmp(client->name, "da9063")) ||
(client->addr == 0x68 && !strcmp(client->name, "da9210")) ||
(client->addr == 0x70 && !strcmp(client->name, "da9210"))) {
int ret, len;
/* There are two DA9210 on Stout, one on the other boards. */
len = of_machine_is_compatible("renesas,stout") ? 3 : 2;
dev_info(&client->dev, "clearing da9063/da9210 interrupts\n");
ret = i2c_transfer(client->adapter, da9xxx_msgs, len);
if (ret != len)
dev_err(&client->dev, "i2c error %d\n", ret);
}
mon = ioread32(irqc + IRQC_MONITOR);
if (mon & REGULATOR_IRQ_MASK)
goto remove;
return 0;
remove:
dev_info(dev, "IRQ2 is not asserted, removing quirk\n");
done = true;
iounmap(irqc);
return 0;
}
static struct notifier_block regulator_quirk_nb = {
.notifier_call = regulator_quirk_notify
};
static int __init rcar_gen2_regulator_quirk(void)
{
u32 mon;
if (!of_machine_is_compatible("renesas,koelsch") &&
!of_machine_is_compatible("renesas,lager") &&
!of_machine_is_compatible("renesas,stout") &&
!of_machine_is_compatible("renesas,gose"))
return -ENODEV;
irqc = ioremap(IRQC_BASE, PAGE_SIZE);
if (!irqc)
return -ENOMEM;
mon = ioread32(irqc + IRQC_MONITOR);
if (mon & REGULATOR_IRQ_MASK) {
pr_debug("%s: IRQ2 is not asserted, not installing quirk\n",
__func__);
iounmap(irqc);
return 0;
}
pr_info("IRQ2 is asserted, installing da9063/da9210 regulator quirk\n");
bus_register_notifier(&i2c_bus_type, ®ulator_quirk_nb);
return 0;
}
arch_initcall(rcar_gen2_regulator_quirk);
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