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 /* start of DA9210 System Control and Event Registers */ 45 #define DA9210_REG_MASK_A 0x54 46 47 static void __iomem *irqc; 48 49 /* first byte sets the memory pointer, following are consecutive reg values */ 50 static u8 da9063_irq_clr[] = { DA9063_REG_IRQ_MASK_A, 0xff, 0xff, 0xff, 0xff }; 51 static u8 da9210_irq_clr[] = { DA9210_REG_MASK_A, 0xff, 0xff }; 52 53 static struct i2c_msg da9xxx_msgs[2] = { 54 { 55 .addr = 0x58, 56 .len = ARRAY_SIZE(da9063_irq_clr), 57 .buf = da9063_irq_clr, 58 }, { 59 .addr = 0x68, 60 .len = ARRAY_SIZE(da9210_irq_clr), 61 .buf = da9210_irq_clr, 62 }, 63 }; 64 65 static int regulator_quirk_notify(struct notifier_block *nb, 66 unsigned long action, void *data) 67 { 68 struct device *dev = data; 69 struct i2c_client *client; 70 static bool done; 71 u32 mon; 72 73 if (done) 74 return 0; 75 76 mon = ioread32(irqc + IRQC_MONITOR); 77 dev_dbg(dev, "%s: %ld, IRQC_MONITOR = 0x%x\n", __func__, action, mon); 78 if (mon & REGULATOR_IRQ_MASK) 79 goto remove; 80 81 if (action != BUS_NOTIFY_ADD_DEVICE || dev->type == &i2c_adapter_type) 82 return 0; 83 84 client = to_i2c_client(dev); 85 dev_dbg(dev, "Detected %s\n", client->name); 86 87 if ((client->addr == 0x58 && !strcmp(client->name, "da9063")) || 88 (client->addr == 0x68 && !strcmp(client->name, "da9210"))) { 89 int ret; 90 91 dev_info(&client->dev, "clearing da9063/da9210 interrupts\n"); 92 ret = i2c_transfer(client->adapter, da9xxx_msgs, ARRAY_SIZE(da9xxx_msgs)); 93 if (ret != ARRAY_SIZE(da9xxx_msgs)) 94 dev_err(&client->dev, "i2c error %d\n", ret); 95 } 96 97 mon = ioread32(irqc + IRQC_MONITOR); 98 if (mon & REGULATOR_IRQ_MASK) 99 goto remove; 100 101 return 0; 102 103 remove: 104 dev_info(dev, "IRQ2 is not asserted, removing quirk\n"); 105 106 done = true; 107 iounmap(irqc); 108 return 0; 109 } 110 111 static struct notifier_block regulator_quirk_nb = { 112 .notifier_call = regulator_quirk_notify 113 }; 114 115 static int __init rcar_gen2_regulator_quirk(void) 116 { 117 u32 mon; 118 119 if (!of_machine_is_compatible("renesas,koelsch") && 120 !of_machine_is_compatible("renesas,lager") && 121 !of_machine_is_compatible("renesas,gose")) 122 return -ENODEV; 123 124 irqc = ioremap(IRQC_BASE, PAGE_SIZE); 125 if (!irqc) 126 return -ENOMEM; 127 128 mon = ioread32(irqc + IRQC_MONITOR); 129 if (mon & REGULATOR_IRQ_MASK) { 130 pr_debug("%s: IRQ2 is not asserted, not installing quirk\n", 131 __func__); 132 iounmap(irqc); 133 return 0; 134 } 135 136 pr_info("IRQ2 is asserted, installing da9063/da9210 regulator quirk\n"); 137 138 bus_register_notifier(&i2c_bus_type, ®ulator_quirk_nb); 139 return 0; 140 } 141 142 arch_initcall(rcar_gen2_regulator_quirk); 143