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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:02:30 +0000
commit76cb841cb886eef6b3bee341a2266c76578724ad (patch)
treef5892e5ba6cc11949952a6ce4ecbe6d516d6ce58 /arch/arm/mach-shmobile/regulator-quirk-rcar-gen2.c
parentInitial commit. (diff)
downloadlinux-76cb841cb886eef6b3bee341a2266c76578724ad.tar.xz
linux-76cb841cb886eef6b3bee341a2266c76578724ad.zip
Adding upstream version 4.19.249.upstream/4.19.249
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/arm/mach-shmobile/regulator-quirk-rcar-gen2.c')
-rw-r--r--arch/arm/mach-shmobile/regulator-quirk-rcar-gen2.c143
1 files changed, 143 insertions, 0 deletions
diff --git a/arch/arm/mach-shmobile/regulator-quirk-rcar-gen2.c b/arch/arm/mach-shmobile/regulator-quirk-rcar-gen2.c
new file mode 100644
index 000000000..21ebc7678
--- /dev/null
+++ b/arch/arm/mach-shmobile/regulator-quirk-rcar-gen2.c
@@ -0,0 +1,143 @@
+// 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, &regulator_quirk_nb);
+ return 0;
+}
+
+arch_initcall(rcar_gen2_regulator_quirk);