[PATCH] gpio: virtio: Fix sparse warnings

From: Viresh Kumar
Date: Tue Aug 31 2021 - 01:29:35 EST


Fix warnings reported by sparse, related to type mismatch between u16
and __le16.

Reported-by: kernel test robot <lkp@xxxxxxxxx>
Fixes: 3a29355a22c0 ("gpio: Add virtio-gpio driver")
Signed-off-by: Viresh Kumar <viresh.kumar@xxxxxxxxxx>
---
drivers/gpio/gpio-virtio.c | 41 ++++++++++++++++----------------
include/uapi/linux/virtio_gpio.h | 10 ++++----
2 files changed, 25 insertions(+), 26 deletions(-)

diff --git a/drivers/gpio/gpio-virtio.c b/drivers/gpio/gpio-virtio.c
index d33eb237c0b9..d24f1c9264bc 100644
--- a/drivers/gpio/gpio-virtio.c
+++ b/drivers/gpio/gpio-virtio.c
@@ -32,7 +32,6 @@ struct virtio_gpio {
struct virtio_device *vdev;
struct mutex lock; /* Protects virtqueue operation */
struct gpio_chip gc;
- struct virtio_gpio_config config;
struct virtio_gpio_line *lines;
struct virtqueue *request_vq;
};
@@ -57,7 +56,7 @@ static int _virtio_gpio_req(struct virtio_gpio *vgpio, u16 type, u16 gpio,

req->type = cpu_to_le16(type);
req->gpio = cpu_to_le16(gpio);
- req->value = txvalue;
+ req->value = cpu_to_le32(txvalue);

sg_init_one(&req_sg, req, sizeof(*req));
sg_init_one(&res_sg, res, rxlen);
@@ -233,19 +232,19 @@ static int virtio_gpio_alloc_vqs(struct virtio_gpio *vgpio,
return 0;
}

-static const char **virtio_gpio_get_names(struct virtio_gpio *vgpio)
+static const char **virtio_gpio_get_names(struct virtio_gpio *vgpio,
+ u32 gpio_names_size, u16 ngpio)
{
- struct virtio_gpio_config *config = &vgpio->config;
struct virtio_gpio_response_get_names *res;
struct device *dev = &vgpio->vdev->dev;
u8 *gpio_names, *str;
const char **names;
int i, ret, len;

- if (!config->gpio_names_size)
+ if (!gpio_names_size)
return NULL;

- len = sizeof(*res) + config->gpio_names_size;
+ len = sizeof(*res) + gpio_names_size;
res = devm_kzalloc(dev, len, GFP_KERNEL);
if (!res)
return NULL;
@@ -258,18 +257,18 @@ static const char **virtio_gpio_get_names(struct virtio_gpio *vgpio)
return NULL;
}

- names = devm_kcalloc(dev, config->ngpio, sizeof(*names), GFP_KERNEL);
+ names = devm_kcalloc(dev, ngpio, sizeof(*names), GFP_KERNEL);
if (!names)
return NULL;

/* NULL terminate the string instead of checking it */
- gpio_names[config->gpio_names_size - 1] = '\0';
+ gpio_names[gpio_names_size - 1] = '\0';

- for (i = 0, str = gpio_names; i < config->ngpio; i++) {
+ for (i = 0, str = gpio_names; i < ngpio; i++) {
names[i] = str;
str += strlen(str) + 1; /* zero-length strings are allowed */

- if (str > gpio_names + config->gpio_names_size) {
+ if (str > gpio_names + gpio_names_size) {
dev_err(dev, "gpio_names block is too short (%d)\n", i);
return NULL;
}
@@ -280,31 +279,31 @@ static const char **virtio_gpio_get_names(struct virtio_gpio *vgpio)

static int virtio_gpio_probe(struct virtio_device *vdev)
{
- struct virtio_gpio_config *config;
+ struct virtio_gpio_config config;
struct device *dev = &vdev->dev;
struct virtio_gpio *vgpio;
+ u32 gpio_names_size;
+ u16 ngpio;
int ret, i;

vgpio = devm_kzalloc(dev, sizeof(*vgpio), GFP_KERNEL);
if (!vgpio)
return -ENOMEM;

- config = &vgpio->config;
-
/* Read configuration */
- virtio_cread_bytes(vdev, 0, config, sizeof(*config));
- config->gpio_names_size = le32_to_cpu(config->gpio_names_size);
- config->ngpio = le16_to_cpu(config->ngpio);
- if (!config->ngpio) {
+ virtio_cread_bytes(vdev, 0, &config, sizeof(config));
+ gpio_names_size = le32_to_cpu(config.gpio_names_size);
+ ngpio = le16_to_cpu(config.ngpio);
+ if (!ngpio) {
dev_err(dev, "Number of GPIOs can't be zero\n");
return -EINVAL;
}

- vgpio->lines = devm_kcalloc(dev, config->ngpio, sizeof(*vgpio->lines), GFP_KERNEL);
+ vgpio->lines = devm_kcalloc(dev, ngpio, sizeof(*vgpio->lines), GFP_KERNEL);
if (!vgpio->lines)
return -ENOMEM;

- for (i = 0; i < config->ngpio; i++) {
+ for (i = 0; i < ngpio; i++) {
mutex_init(&vgpio->lines[i].lock);
init_completion(&vgpio->lines[i].completion);
}
@@ -319,7 +318,7 @@ static int virtio_gpio_probe(struct virtio_device *vdev)
vgpio->gc.direction_output = virtio_gpio_direction_output;
vgpio->gc.get = virtio_gpio_get;
vgpio->gc.set = virtio_gpio_set;
- vgpio->gc.ngpio = config->ngpio;
+ vgpio->gc.ngpio = ngpio;
vgpio->gc.base = -1; /* Allocate base dynamically */
vgpio->gc.label = dev_name(dev);
vgpio->gc.parent = dev;
@@ -333,7 +332,7 @@ static int virtio_gpio_probe(struct virtio_device *vdev)
/* Mark the device ready to perform operations from within probe() */
virtio_device_ready(vdev);

- vgpio->gc.names = virtio_gpio_get_names(vgpio);
+ vgpio->gc.names = virtio_gpio_get_names(vgpio, gpio_names_size, ngpio);

ret = gpiochip_add_data(&vgpio->gc, vgpio);
if (ret) {
diff --git a/include/uapi/linux/virtio_gpio.h b/include/uapi/linux/virtio_gpio.h
index 844574acf095..0445f905d8cc 100644
--- a/include/uapi/linux/virtio_gpio.h
+++ b/include/uapi/linux/virtio_gpio.h
@@ -22,16 +22,16 @@
#define VIRTIO_GPIO_DIRECTION_IN 0x02

struct virtio_gpio_config {
- __u16 ngpio;
+ __le16 ngpio;
__u8 padding[2];
- __u32 gpio_names_size;
+ __le32 gpio_names_size;
} __packed;

/* Virtio GPIO Request / Response */
struct virtio_gpio_request {
- __u16 type;
- __u16 gpio;
- __u32 value;
+ __le16 type;
+ __le16 gpio;
+ __le32 value;
};

struct virtio_gpio_response {
--
2.31.1.272.g89b43f80a514