From 7a7b5df84b6b4e5d599c7289526eed96541a0654 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 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") Cc: stable # 4.9 Signed-off-by: Johan Hovold Reviewed-by: Benjamin Tissoires Signed-off-by: Jiri Kosina --- 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 f31a778b0851..3e0b6bad29f2 100644 --- a/drivers/hid/hid-cp2112.c +++ b/drivers/hid/hid-cp2112.c @@ -168,7 +168,7 @@ struct cp2112_device { atomic_t xfer_avail; struct gpio_chip gc; u8 *in_out_buffer; - spinlock_t lock; + struct mutex lock; struct gpio_desc *desc[8]; bool gpio_poll; @@ -186,10 +186,9 @@ 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, @@ -213,7 +212,7 @@ 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; } @@ -222,10 +221,9 @@ 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; @@ -237,7 +235,7 @@ 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_all(struct gpio_chip *chip) @@ -245,10 +243,9 @@ static int cp2112_gpio_get_all(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_GET, buf, CP2112_GPIO_GET_LENGTH, HID_FEATURE_REPORT, @@ -262,7 +259,7 @@ static int cp2112_gpio_get_all(struct gpio_chip *chip) ret = buf[1]; exit: - spin_unlock_irqrestore(&dev->lock, flags); + mutex_unlock(&dev->lock); return ret; } @@ -284,10 +281,9 @@ 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, @@ -308,7 +304,7 @@ 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, @@ -319,7 +315,7 @@ 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; } @@ -1235,7 +1231,7 @@ 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