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HID: cp2112: fix sleep-while-atomic

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commit 7a7b5df84b6b4e5d599c7289526eed96541a0654 upstream.

A recent commit fixing DMA-buffers on stack added a shared transfer
buffer protected by a spinlock. This is broken as the USB HID request
callbacks can sleep. Fix this up by replacing the spinlock with a mutex.

Fixes: 1ffb3c40ffb5 ("HID: cp2112: make transfer buffers DMA capable")
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Benjamin Tissoires <benjamin.tissoires@redhat.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Johan Hovold 2017-01-30 11:26:38 +01:00 committed by Greg Kroah-Hartman
parent dfd713307a
commit a18c4584a4
1 changed files with 11 additions and 15 deletions
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26
drivers/hid/hid-cp2112.c
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@ -167,7 +167,7 @@ struct cp2112_device {
atomic_t xfer_avail;
struct gpio_chip gc;
u8 *in_out_buffer;
spinlock_t lock;
struct mutex lock;
};
static int gpio_push_pull = 0xFF;
@ -179,10 +179,9 @@ static int cp2112_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
struct cp2112_device *dev = gpiochip_get_data(chip);
struct hid_device *hdev = dev->hdev;
u8 *buf = dev->in_out_buffer;
unsigned long flags;
int ret;
spin_lock_irqsave(&dev->lock, flags);
mutex_lock(&dev->lock);
ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
@ -206,7 +205,7 @@ static int cp2112_gpio_direction_input(struct gpio_chip *chip, unsigned offset)
ret = 0;
exit:
spin_unlock_irqrestore(&dev->lock, flags);
mutex_unlock(&dev->lock);
return ret <= 0 ? ret : -EIO;
}
@ -215,10 +214,9 @@ static void cp2112_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
struct cp2112_device *dev = gpiochip_get_data(chip);
struct hid_device *hdev = dev->hdev;
u8 *buf = dev->in_out_buffer;
unsigned long flags;
int ret;
spin_lock_irqsave(&dev->lock, flags);
mutex_lock(&dev->lock);
buf[0] = CP2112_GPIO_SET;
buf[1] = value ? 0xff : 0;
@ -230,7 +228,7 @@ static void cp2112_gpio_set(struct gpio_chip *chip, unsigned offset, int value)
if (ret < 0)
hid_err(hdev, "error setting GPIO values: %d\n", ret);
spin_unlock_irqrestore(&dev->lock, flags);
mutex_unlock(&dev->lock);
}
static int cp2112_gpio_get(struct gpio_chip *chip, unsigned offset)
@ -238,10 +236,9 @@ static int cp2112_gpio_get(struct gpio_chip *chip, unsigned offset)
struct cp2112_device *dev = gpiochip_get_data(chip);
struct hid_device *hdev = dev->hdev;
u8 *buf = dev->in_out_buffer;
unsigned long flags;
int ret;
spin_lock_irqsave(&dev->lock, flags);
mutex_lock(&dev->lock);
ret = hid_hw_raw_request(hdev, CP2112_GPIO_GET, buf,
CP2112_GPIO_GET_LENGTH, HID_FEATURE_REPORT,
@ -255,7 +252,7 @@ static int cp2112_gpio_get(struct gpio_chip *chip, unsigned offset)
ret = (buf[1] >> offset) & 1;
exit:
spin_unlock_irqrestore(&dev->lock, flags);
mutex_unlock(&dev->lock);
return ret;
}
@ -266,10 +263,9 @@ static int cp2112_gpio_direction_output(struct gpio_chip *chip,
struct cp2112_device *dev = gpiochip_get_data(chip);
struct hid_device *hdev = dev->hdev;
u8 *buf = dev->in_out_buffer;
unsigned long flags;
int ret;
spin_lock_irqsave(&dev->lock, flags);
mutex_lock(&dev->lock);
ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf,
CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT,
@ -290,7 +286,7 @@ static int cp2112_gpio_direction_output(struct gpio_chip *chip,
goto fail;
}
spin_unlock_irqrestore(&dev->lock, flags);
mutex_unlock(&dev->lock);
/*
* Set gpio value when output direction is already set,
@ -301,7 +297,7 @@ static int cp2112_gpio_direction_output(struct gpio_chip *chip,
return 0;
fail:
spin_unlock_irqrestore(&dev->lock, flags);
mutex_unlock(&dev->lock);
return ret < 0 ? ret : -EIO;
}
@ -1057,7 +1053,7 @@ static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id)
if (!dev->in_out_buffer)
return -ENOMEM;
spin_lock_init(&dev->lock);
mutex_init(&dev->lock);
ret = hid_parse(hdev);
if (ret) {