1 /* 2 * R-Car Generation 2 da9063/da9210 regulator quirk 3 * 4 * The r8a7790/lager and r8a7791/koelsch development boards have da9063 and 5 * da9210 regulators. Both regulators have their interrupt request lines tied 6 * to the same interrupt pin (IRQ2) on the SoC. 7 * 8 * After cold boot or da9063-induced restart, both the da9063 and da9210 seem 9 * to assert their interrupt request lines. Hence as soon as one driver 10 * requests this irq, it gets stuck in an interrupt storm, as it only manages 11 * to deassert its own interrupt request line, and the other driver hasn't 12 * installed an interrupt handler yet. 13 * 14 * To handle this, install a quirk that masks the interrupts in both the 15 * da9063 and da9210. This quirk has to run after the i2c master driver has 16 * been initialized, but before the i2c slave drivers are initialized. 17 * 18 * Copyright (C) 2015 Glider bvba 19 * 20 * This program is free software; you can redistribute it and/or modify 21 * it under the terms of the GNU General Public License as published by 22 * the Free Software Foundation; version 2 of the License. 23 * 24 * This program is distributed in the hope that it will be useful, 25 * but WITHOUT ANY WARRANTY; without even the implied warranty of 26 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 27 * GNU General Public License for more details. 28 */ 29 30 #include <linux/device.h> 31 #include <linux/i2c.h> 32 #include <linux/init.h> 33 #include <linux/io.h> 34 #include <linux/notifier.h> 35 #include <linux/of.h> 36 #include <linux/mfd/da9063/registers.h> 37 38 39 #define IRQC_BASE 0xe61c0000 40 #define IRQC_MONITOR 0x104 /* IRQn Signal Level Monitor Register */ 41 42 #define REGULATOR_IRQ_MASK BIT(2) /* IRQ2, active low */ 43 44 static void __iomem *irqc; 45 46 static const u8 da9063_mask_regs[] = { 47 DA9063_REG_IRQ_MASK_A, 48 DA9063_REG_IRQ_MASK_B, 49 DA9063_REG_IRQ_MASK_C, 50 DA9063_REG_IRQ_MASK_D, 51 }; 52 53 /* DA9210 System Control and Event Registers */ 54 #define DA9210_REG_MASK_A 0x54 55 #define DA9210_REG_MASK_B 0x55 56 57 static const u8 da9210_mask_regs[] = { 58 DA9210_REG_MASK_A, 59 DA9210_REG_MASK_B, 60 }; 61 62 static void da9xxx_mask_irqs(struct i2c_client *client, const u8 regs[], 63 unsigned int nregs) 64 { 65 unsigned int i; 66 67 dev_info(&client->dev, "Masking %s interrupt sources\n", client->name); 68 69 for (i = 0; i < nregs; i++) { 70 int error = i2c_smbus_write_byte_data(client, regs[i], ~0); 71 if (error) { 72 dev_err(&client->dev, "i2c error %d\n", error); 73 return; 74 } 75 } 76 } 77 78 static int regulator_quirk_notify(struct notifier_block *nb, 79 unsigned long action, void *data) 80 { 81 struct device *dev = data; 82 struct i2c_client *client; 83 u32 mon; 84 85 mon = ioread32(irqc + IRQC_MONITOR); 86 dev_dbg(dev, "%s: %ld, IRQC_MONITOR = 0x%x\n", __func__, action, mon); 87 if (mon & REGULATOR_IRQ_MASK) 88 goto remove; 89 90 if (action != BUS_NOTIFY_ADD_DEVICE || dev->type == &i2c_adapter_type) 91 return 0; 92 93 client = to_i2c_client(dev); 94 dev_dbg(dev, "Detected %s\n", client->name); 95 96 if ((client->addr == 0x58 && !strcmp(client->name, "da9063"))) 97 da9xxx_mask_irqs(client, da9063_mask_regs, 98 ARRAY_SIZE(da9063_mask_regs)); 99 else if (client->addr == 0x68 && !strcmp(client->name, "da9210")) 100 da9xxx_mask_irqs(client, da9210_mask_regs, 101 ARRAY_SIZE(da9210_mask_regs)); 102 103 mon = ioread32(irqc + IRQC_MONITOR); 104 if (mon & REGULATOR_IRQ_MASK) 105 goto remove; 106 107 return 0; 108 109 remove: 110 dev_info(dev, "IRQ2 is not asserted, removing quirk\n"); 111 112 bus_unregister_notifier(&i2c_bus_type, nb); 113 iounmap(irqc); 114 return 0; 115 } 116 117 static struct notifier_block regulator_quirk_nb = { 118 .notifier_call = regulator_quirk_notify 119 }; 120 121 static int __init rcar_gen2_regulator_quirk(void) 122 { 123 u32 mon; 124 125 if (!of_machine_is_compatible("renesas,koelsch") && 126 !of_machine_is_compatible("renesas,lager") && 127 !of_machine_is_compatible("renesas,gose")) 128 return -ENODEV; 129 130 irqc = ioremap(IRQC_BASE, PAGE_SIZE); 131 if (!irqc) 132 return -ENOMEM; 133 134 mon = ioread32(irqc + IRQC_MONITOR); 135 if (mon & REGULATOR_IRQ_MASK) { 136 pr_debug("%s: IRQ2 is not asserted, not installing quirk\n", 137 __func__); 138 iounmap(irqc); 139 return 0; 140 } 141 142 pr_info("IRQ2 is asserted, installing da9063/da9210 regulator quirk\n"); 143 144 bus_register_notifier(&i2c_bus_type, ®ulator_quirk_nb); 145 return 0; 146 } 147 148 arch_initcall(rcar_gen2_regulator_quirk); 149