Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/drivers/i2c/busses/i2c-gpio.c b/drivers/i2c/busses/i2c-gpio.c
index c008d20..3a9e840 100644
--- a/drivers/i2c/busses/i2c-gpio.c
+++ b/drivers/i2c/busses/i2c-gpio.c
@@ -1,23 +1,22 @@
+// SPDX-License-Identifier: GPL-2.0-only
/*
* Bitbanging I2C bus driver using the GPIO API
*
* Copyright (C) 2007 Atmel Corporation
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
*/
+#include <linux/completion.h>
#include <linux/debugfs.h>
#include <linux/delay.h>
-#include <linux/i2c.h>
-#include <linux/i2c-algo-bit.h>
-#include <linux/platform_data/i2c-gpio.h>
-#include <linux/init.h>
-#include <linux/module.h>
-#include <linux/slab.h>
-#include <linux/platform_device.h>
#include <linux/gpio/consumer.h>
+#include <linux/i2c-algo-bit.h>
+#include <linux/i2c.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
#include <linux/of.h>
+#include <linux/platform_data/i2c-gpio.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
struct i2c_gpio_private_data {
struct gpio_desc *sda;
@@ -27,6 +26,9 @@
struct i2c_gpio_platform_data pdata;
#ifdef CONFIG_I2C_GPIO_FAULT_INJECTOR
struct dentry *debug_dir;
+ /* these must be protected by bus lock */
+ struct completion scl_irq_completion;
+ u64 scl_irq_data;
#endif
};
@@ -162,6 +164,96 @@
}
DEFINE_DEBUGFS_ATTRIBUTE(fops_incomplete_write_byte, NULL, fops_incomplete_write_byte_set, "%llu\n");
+static int i2c_gpio_fi_act_on_scl_irq(struct i2c_gpio_private_data *priv,
+ irqreturn_t handler(int, void*))
+{
+ int ret, irq = gpiod_to_irq(priv->scl);
+
+ if (irq < 0)
+ return irq;
+
+ i2c_lock_bus(&priv->adap, I2C_LOCK_ROOT_ADAPTER);
+
+ ret = gpiod_direction_input(priv->scl);
+ if (ret)
+ goto unlock;
+
+ reinit_completion(&priv->scl_irq_completion);
+
+ ret = request_irq(irq, handler, IRQF_TRIGGER_FALLING,
+ "i2c_gpio_fault_injector_scl_irq", priv);
+ if (ret)
+ goto output;
+
+ wait_for_completion_interruptible(&priv->scl_irq_completion);
+
+ free_irq(irq, priv);
+ output:
+ ret = gpiod_direction_output(priv->scl, 1) ?: ret;
+ unlock:
+ i2c_unlock_bus(&priv->adap, I2C_LOCK_ROOT_ADAPTER);
+
+ return ret;
+}
+
+static irqreturn_t lose_arbitration_irq(int irq, void *dev_id)
+{
+ struct i2c_gpio_private_data *priv = dev_id;
+
+ setsda(&priv->bit_data, 0);
+ udelay(priv->scl_irq_data);
+ setsda(&priv->bit_data, 1);
+
+ complete(&priv->scl_irq_completion);
+
+ return IRQ_HANDLED;
+}
+
+static int fops_lose_arbitration_set(void *data, u64 duration)
+{
+ struct i2c_gpio_private_data *priv = data;
+
+ if (duration > 100 * 1000)
+ return -EINVAL;
+
+ priv->scl_irq_data = duration;
+ /*
+ * Interrupt on falling SCL. This ensures that the master under test has
+ * really started the transfer. Interrupt on falling SDA did only
+ * exercise 'bus busy' detection on some HW but not 'arbitration lost'.
+ * Note that the interrupt latency may cause the first bits to be
+ * transmitted correctly.
+ */
+ return i2c_gpio_fi_act_on_scl_irq(priv, lose_arbitration_irq);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(fops_lose_arbitration, NULL, fops_lose_arbitration_set, "%llu\n");
+
+static irqreturn_t inject_panic_irq(int irq, void *dev_id)
+{
+ struct i2c_gpio_private_data *priv = dev_id;
+
+ udelay(priv->scl_irq_data);
+ panic("I2C fault injector induced panic");
+
+ return IRQ_HANDLED;
+}
+
+static int fops_inject_panic_set(void *data, u64 duration)
+{
+ struct i2c_gpio_private_data *priv = data;
+
+ if (duration > 100 * 1000)
+ return -EINVAL;
+
+ priv->scl_irq_data = duration;
+ /*
+ * Interrupt on falling SCL. This ensures that the master under test has
+ * really started the transfer.
+ */
+ return i2c_gpio_fi_act_on_scl_irq(priv, inject_panic_irq);
+}
+DEFINE_DEBUGFS_ATTRIBUTE(fops_inject_panic, NULL, fops_inject_panic_set, "%llu\n");
+
static void i2c_gpio_fault_injector_init(struct platform_device *pdev)
{
struct i2c_gpio_private_data *priv = platform_get_drvdata(pdev);
@@ -181,12 +273,20 @@
if (!priv->debug_dir)
return;
- debugfs_create_file_unsafe("scl", 0600, priv->debug_dir, priv, &fops_scl);
- debugfs_create_file_unsafe("sda", 0600, priv->debug_dir, priv, &fops_sda);
+ init_completion(&priv->scl_irq_completion);
+
debugfs_create_file_unsafe("incomplete_address_phase", 0200, priv->debug_dir,
priv, &fops_incomplete_addr_phase);
debugfs_create_file_unsafe("incomplete_write_byte", 0200, priv->debug_dir,
priv, &fops_incomplete_write_byte);
+ if (priv->bit_data.getscl) {
+ debugfs_create_file_unsafe("inject_panic", 0200, priv->debug_dir,
+ priv, &fops_inject_panic);
+ debugfs_create_file_unsafe("lose_arbitration", 0200, priv->debug_dir,
+ priv, &fops_lose_arbitration);
+ }
+ debugfs_create_file_unsafe("scl", 0600, priv->debug_dir, priv, &fops_scl);
+ debugfs_create_file_unsafe("sda", 0600, priv->debug_dir, priv, &fops_sda);
}
static void i2c_gpio_fault_injector_exit(struct platform_device *pdev)
@@ -286,11 +386,11 @@
/*
* First get the GPIO pins; if it fails, we'll defer the probe.
- * If the SDA line is marked from platform data or device tree as
- * "open drain" it means something outside of our control is making
- * this line being handled as open drain, and we should just handle
- * it as any other output. Else we enforce open drain as this is
- * required for an I2C bus.
+ * If the SCL/SDA lines are marked "open drain" by platform data or
+ * device tree then this means that something outside of our control is
+ * marking these lines to be handled as open drain, and we should just
+ * handle them as we handle any other output. Else we enforce open
+ * drain as this is required for an I2C bus.
*/
if (pdata->sda_is_open_drain)
gflags = GPIOD_OUT_HIGH;
@@ -300,13 +400,6 @@
if (IS_ERR(priv->sda))
return PTR_ERR(priv->sda);
- /*
- * If the SCL line is marked from platform data or device tree as
- * "open drain" it means something outside of our control is making
- * this line being handled as open drain, and we should just handle
- * it as any other output. Else we enforce open drain as this is
- * required for an I2C bus.
- */
if (pdata->scl_is_open_drain)
gflags = GPIOD_OUT_HIGH;
else
@@ -317,6 +410,8 @@
if (gpiod_cansleep(priv->sda) || gpiod_cansleep(priv->scl))
dev_warn(dev, "Slow GPIO pins might wreak havoc into I2C/SMBus bus timing");
+ else
+ bit_data->can_do_atomic = true;
bit_data->setsda = i2c_gpio_setsda_val;
bit_data->setscl = i2c_gpio_setscl_val;