Merge remote-tracking branch 'lsk/v3.10/topic/configs' into linux-linaro-lsk
[firefly-linux-kernel-4.4.55.git] / drivers / media / dvb-frontends / cxd2820r_core.c
index 7ca5c69dd2007202c2f3492615019f0055393558..03930d5e9fea4cbf2a5787aad71d08af809544fa 100644 (file)
 
 #include "cxd2820r_priv.h"
 
+/* Max transfer size done by I2C transfer functions */
+#define MAX_XFER_SIZE  64
+
 /* write multiple registers */
 static int cxd2820r_wr_regs_i2c(struct cxd2820r_priv *priv, u8 i2c, u8 reg,
        u8 *val, int len)
 {
        int ret;
-       u8 buf[len+1];
+       u8 buf[MAX_XFER_SIZE];
        struct i2c_msg msg[1] = {
                {
                        .addr = i2c,
                        .flags = 0,
-                       .len = sizeof(buf),
+                       .len = len + 1,
                        .buf = buf,
                }
        };
 
+       if (1 + len > sizeof(buf)) {
+               dev_warn(&priv->i2c->dev,
+                        "%s: i2c wr reg=%04x: len=%d is too big!\n",
+                        KBUILD_MODNAME, reg, len);
+               return -EINVAL;
+       }
+
        buf[0] = reg;
        memcpy(&buf[1], val, len);
 
@@ -55,7 +65,7 @@ static int cxd2820r_rd_regs_i2c(struct cxd2820r_priv *priv, u8 i2c, u8 reg,
        u8 *val, int len)
 {
        int ret;
-       u8 buf[len];
+       u8 buf[MAX_XFER_SIZE];
        struct i2c_msg msg[2] = {
                {
                        .addr = i2c,
@@ -65,11 +75,18 @@ static int cxd2820r_rd_regs_i2c(struct cxd2820r_priv *priv, u8 i2c, u8 reg,
                }, {
                        .addr = i2c,
                        .flags = I2C_M_RD,
-                       .len = sizeof(buf),
+                       .len = len,
                        .buf = buf,
                }
        };
 
+       if (len > sizeof(buf)) {
+               dev_warn(&priv->i2c->dev,
+                        "%s: i2c wr reg=%04x: len=%d is too big!\n",
+                        KBUILD_MODNAME, reg, len);
+               return -EINVAL;
+       }
+
        ret = i2c_transfer(priv->i2c, msg, 2);
        if (ret == 2) {
                memcpy(val, buf, len);