From 1ffb3c40ffb5c51bc39736409b11816c4260218e Mon Sep 17 00:00:00 2001 From: Benjamin Tissoires Date: Mon, 21 Nov 2016 11:48:39 +0100 Subject: [PATCH] HID: cp2112: make transfer buffers DMA capable Kernel v4.9 strictly enforces DMA capable buffers, so we need to remove buffers allocated on the stack. Use a spinlock to prevent concurrent accesses to the buffer. Signed-off-by: Benjamin Tissoires Signed-off-by: Jiri Kosina --- drivers/hid/hid-cp2112.c | 115 +++++++++++++++++++++++++++------------ 1 file changed, 79 insertions(+), 36 deletions(-) diff --git a/drivers/hid/hid-cp2112.c b/drivers/hid/hid-cp2112.c index 086d8a507157..60d30203a5fa 100644 --- a/drivers/hid/hid-cp2112.c +++ b/drivers/hid/hid-cp2112.c @@ -32,6 +32,11 @@ #include #include "hid-ids.h" +#define CP2112_REPORT_MAX_LENGTH 64 +#define CP2112_GPIO_CONFIG_LENGTH 5 +#define CP2112_GPIO_GET_LENGTH 2 +#define CP2112_GPIO_SET_LENGTH 3 + enum { CP2112_GPIO_CONFIG = 0x02, CP2112_GPIO_GET = 0x03, @@ -161,6 +166,8 @@ struct cp2112_device { atomic_t read_avail; atomic_t xfer_avail; struct gpio_chip gc; + u8 *in_out_buffer; + spinlock_t lock; }; static int gpio_push_pull = 0xFF; @@ -171,62 +178,86 @@ 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[5]; + u8 *buf = dev->in_out_buffer; + unsigned long flags; int ret; + spin_lock_irqsave(&dev->lock, flags); + ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf, - sizeof(buf), HID_FEATURE_REPORT, - HID_REQ_GET_REPORT); - if (ret != sizeof(buf)) { + CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT, + HID_REQ_GET_REPORT); + if (ret != CP2112_GPIO_CONFIG_LENGTH) { hid_err(hdev, "error requesting GPIO config: %d\n", ret); - return ret; + goto exit; } buf[1] &= ~(1 << offset); buf[2] = gpio_push_pull; - ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf, sizeof(buf), - HID_FEATURE_REPORT, HID_REQ_SET_REPORT); + ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf, + CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT, + HID_REQ_SET_REPORT); if (ret < 0) { hid_err(hdev, "error setting GPIO config: %d\n", ret); - return ret; + goto exit; } - return 0; + ret = 0; + +exit: + spin_unlock_irqrestore(&dev->lock, flags); + return ret <= 0 ? ret : -EIO; } 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[3]; + u8 *buf = dev->in_out_buffer; + unsigned long flags; int ret; + spin_lock_irqsave(&dev->lock, flags); + buf[0] = CP2112_GPIO_SET; buf[1] = value ? 0xff : 0; buf[2] = 1 << offset; - ret = hid_hw_raw_request(hdev, CP2112_GPIO_SET, buf, sizeof(buf), - HID_FEATURE_REPORT, HID_REQ_SET_REPORT); + ret = hid_hw_raw_request(hdev, CP2112_GPIO_SET, buf, + CP2112_GPIO_SET_LENGTH, HID_FEATURE_REPORT, + HID_REQ_SET_REPORT); if (ret < 0) hid_err(hdev, "error setting GPIO values: %d\n", ret); + + spin_unlock_irqrestore(&dev->lock, flags); } 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[2]; + u8 *buf = dev->in_out_buffer; + unsigned long flags; int ret; - ret = hid_hw_raw_request(hdev, CP2112_GPIO_GET, buf, sizeof(buf), - HID_FEATURE_REPORT, HID_REQ_GET_REPORT); - if (ret != sizeof(buf)) { + spin_lock_irqsave(&dev->lock, flags); + + ret = hid_hw_raw_request(hdev, CP2112_GPIO_GET, buf, + CP2112_GPIO_GET_LENGTH, HID_FEATURE_REPORT, + HID_REQ_GET_REPORT); + if (ret != CP2112_GPIO_GET_LENGTH) { hid_err(hdev, "error requesting GPIO values: %d\n", ret); - return ret; + ret = ret < 0 ? ret : -EIO; + goto exit; } - return (buf[1] >> offset) & 1; + ret = (buf[1] >> offset) & 1; + +exit: + spin_unlock_irqrestore(&dev->lock, flags); + + return ret; } static int cp2112_gpio_direction_output(struct gpio_chip *chip, @@ -234,27 +265,33 @@ 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[5]; + u8 *buf = dev->in_out_buffer; + unsigned long flags; int ret; + spin_lock_irqsave(&dev->lock, flags); + ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf, - sizeof(buf), HID_FEATURE_REPORT, - HID_REQ_GET_REPORT); - if (ret != sizeof(buf)) { + CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT, + HID_REQ_GET_REPORT); + if (ret != CP2112_GPIO_CONFIG_LENGTH) { hid_err(hdev, "error requesting GPIO config: %d\n", ret); - return ret; + goto fail; } buf[1] |= 1 << offset; buf[2] = gpio_push_pull; - ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf, sizeof(buf), - HID_FEATURE_REPORT, HID_REQ_SET_REPORT); + ret = hid_hw_raw_request(hdev, CP2112_GPIO_CONFIG, buf, + CP2112_GPIO_CONFIG_LENGTH, HID_FEATURE_REPORT, + HID_REQ_SET_REPORT); if (ret < 0) { hid_err(hdev, "error setting GPIO config: %d\n", ret); - return ret; + goto fail; } + spin_unlock_irqrestore(&dev->lock, flags); + /* * Set gpio value when output direction is already set, * as specified in AN495, Rev. 0.2, cpt. 4.4 @@ -262,6 +299,10 @@ static int cp2112_gpio_direction_output(struct gpio_chip *chip, cp2112_gpio_set(chip, offset, value); return 0; + +fail: + spin_unlock_irqrestore(&dev->lock, flags); + return ret < 0 ? ret : -EIO; } static int cp2112_hid_get(struct hid_device *hdev, unsigned char report_number, @@ -1007,6 +1048,17 @@ static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id) struct cp2112_smbus_config_report config; int ret; + dev = devm_kzalloc(&hdev->dev, sizeof(*dev), GFP_KERNEL); + if (!dev) + return -ENOMEM; + + dev->in_out_buffer = devm_kzalloc(&hdev->dev, CP2112_REPORT_MAX_LENGTH, + GFP_KERNEL); + if (!dev->in_out_buffer) + return -ENOMEM; + + spin_lock_init(&dev->lock); + ret = hid_parse(hdev); if (ret) { hid_err(hdev, "parse failed\n"); @@ -1063,12 +1115,6 @@ static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id) goto err_power_normal; } - dev = kzalloc(sizeof(*dev), GFP_KERNEL); - if (!dev) { - ret = -ENOMEM; - goto err_power_normal; - } - hid_set_drvdata(hdev, (void *)dev); dev->hdev = hdev; dev->adap.owner = THIS_MODULE; @@ -1087,7 +1133,7 @@ static int cp2112_probe(struct hid_device *hdev, const struct hid_device_id *id) if (ret) { hid_err(hdev, "error registering i2c adapter\n"); - goto err_free_dev; + goto err_power_normal; } hid_dbg(hdev, "adapter registered\n"); @@ -1123,8 +1169,6 @@ err_gpiochip_remove: gpiochip_remove(&dev->gc); err_free_i2c: i2c_del_adapter(&dev->adap); -err_free_dev: - kfree(dev); err_power_normal: hid_hw_power(hdev, PM_HINT_NORMAL); err_hid_close: @@ -1149,7 +1193,6 @@ static void cp2112_remove(struct hid_device *hdev) */ hid_hw_close(hdev); hid_hw_stop(hdev); - kfree(dev); } static int cp2112_raw_event(struct hid_device *hdev, struct hid_report *report, -- 2.20.1