diff options
Diffstat (limited to 'drivers/media/tuners/e4000.c')
| -rw-r--r-- | drivers/media/tuners/e4000.c | 28 |
1 files changed, 23 insertions, 5 deletions
diff --git a/drivers/media/tuners/e4000.c b/drivers/media/tuners/e4000.c index ad9309da4a91..72971a8d3c37 100644 --- a/drivers/media/tuners/e4000.c +++ b/drivers/media/tuners/e4000.c @@ -19,21 +19,32 @@ */ #include "e4000_priv.h" +#include <linux/math64.h> + +/* Max transfer size done by I2C transfer functions */ +#define MAX_XFER_SIZE 64 /* write multiple registers */ static int e4000_wr_regs(struct e4000_priv *priv, u8 reg, u8 *val, int len) { int ret; - u8 buf[1 + len]; + u8 buf[MAX_XFER_SIZE]; struct i2c_msg msg[1] = { { .addr = priv->cfg->i2c_addr, .flags = 0, - .len = sizeof(buf), + .len = 1 + len, .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); @@ -53,7 +64,7 @@ static int e4000_wr_regs(struct e4000_priv *priv, u8 reg, u8 *val, int len) static int e4000_rd_regs(struct e4000_priv *priv, u8 reg, u8 *val, int len) { int ret; - u8 buf[len]; + u8 buf[MAX_XFER_SIZE]; struct i2c_msg msg[2] = { { .addr = priv->cfg->i2c_addr, @@ -63,11 +74,18 @@ static int e4000_rd_regs(struct e4000_priv *priv, u8 reg, u8 *val, int len) }, { .addr = priv->cfg->i2c_addr, .flags = I2C_M_RD, - .len = sizeof(buf), + .len = len, .buf = buf, } }; + if (len > sizeof(buf)) { + dev_warn(&priv->i2c->dev, + "%s: i2c rd 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); @@ -233,7 +251,7 @@ static int e4000_set_params(struct dvb_frontend *fe) * or more. */ f_vco = c->frequency * e4000_pll_lut[i].mul; - sigma_delta = 0x10000UL * (f_vco % priv->cfg->clock) / priv->cfg->clock; + sigma_delta = div_u64(0x10000ULL * (f_vco % priv->cfg->clock), priv->cfg->clock); buf[0] = f_vco / priv->cfg->clock; buf[1] = (sigma_delta >> 0) & 0xff; buf[2] = (sigma_delta >> 8) & 0xff; |