From a18c4584a48931e8048508469bcdb53c6082221a Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Mon, 30 Jan 2017 11:26:38 +0100 Subject: [PATCH] HID: cp2112: fix sleep-while-atomic 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 Reviewed-by: Benjamin Tissoires Signed-off-by: Jiri Kosina Signed-off-by: Greg Kroah-Hartman --- drivers/hid/hid-cp2112.c | 26 +++++++++++--------------- 1 file changed, 11 insertions(+), 15 deletions(-) diff --git a/drivers/hid/hid-cp2112.c b/drivers/hid/hid-cp2112.c index 60d30203a5fa..ffc941c40a0f 100644 --- a/drivers/hid/hid-cp2112.c +++ b/drivers/hid/hid-cp2112.c @@ -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) { -- 2.39.5