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Release 4.7 arch/arm/mach-shmobile/regulator-quirk-rcar-gen2.c

/*
 * R-Car Generation 2 da9063/da9210 regulator quirk
 *
 * The r8a7790/lager and r8a7791/koelsch development boards have da9063 and
 * da9210 regulators.  Both 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
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; version 2 of the License.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 */

#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 */


static void __iomem *irqc;


static const u8 da9063_mask_regs[] = {
	DA9063_REG_IRQ_MASK_A,
	DA9063_REG_IRQ_MASK_B,
	DA9063_REG_IRQ_MASK_C,
	DA9063_REG_IRQ_MASK_D,
};

/* DA9210 System Control and Event Registers */

#define DA9210_REG_MASK_A		0x54

#define DA9210_REG_MASK_B		0x55


static const u8 da9210_mask_regs[] = {
	DA9210_REG_MASK_A,
	DA9210_REG_MASK_B,
};


static void da9xxx_mask_irqs(struct i2c_client *client, const u8 regs[], unsigned int nregs) { unsigned int i; dev_info(&client->dev, "Masking %s interrupt sources\n", client->name); for (i = 0; i < nregs; i++) { int error = i2c_smbus_write_byte_data(client, regs[i], ~0); if (error) { dev_err(&client->dev, "i2c error %d\n", error); return; } } }

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static int regulator_quirk_notify(struct notifier_block *nb, unsigned long action, void *data) { struct device *dev = data; struct i2c_client *client; u32 mon; 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"))) da9xxx_mask_irqs(client, da9063_mask_regs, ARRAY_SIZE(da9063_mask_regs)); else if (client->addr == 0x68 && !strcmp(client->name, "da9210")) da9xxx_mask_irqs(client, da9210_mask_regs, ARRAY_SIZE(da9210_mask_regs)); 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"); bus_unregister_notifier(&i2c_bus_type, nb); iounmap(irqc); return 0; }

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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,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, &regulator_quirk_nb); return 0; }

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geert uytterhoevengeert uytterhoeven9794.17%150.00%
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arch_initcall(rcar_gen2_regulator_quirk);

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