[media] r820t: split the function that read cached regs
As we'll need to retrieve cached registers, make this
function explicit.
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Tested-by: Antti Palosaari <crope@iki.fi>
diff --git a/drivers/media/tuners/r820t.c b/drivers/media/tuners/r820t.c
index d5686e8..ef100ab 100644
--- a/drivers/media/tuners/r820t.c
+++ b/drivers/media/tuners/r820t.c
@@ -402,15 +402,25 @@
return r820t_write(priv, reg, &val, 1);
}
+static int r820t_read_cache_reg(struct r820t_priv *priv, int reg)
+{
+ reg -= REG_SHADOW_START;
+
+ if (reg >= 0 && reg < NUM_REGS)
+ return priv->regs[reg];
+ else
+ return -EINVAL;
+}
+
static int r820t_write_reg_mask(struct r820t_priv *priv, u8 reg, u8 val,
u8 bit_mask)
{
- int r = reg - REG_SHADOW_START;
+ int rc = r820t_read_cache_reg(priv, reg);
- if (r >= 0 && r < NUM_REGS)
- val = (priv->regs[r] & ~bit_mask) | (val & bit_mask);
- else
- return -EINVAL;
+ if (rc < 0)
+ return rc;
+
+ val = (rc & ~bit_mask) | (val & bit_mask);
return r820t_write(priv, reg, &val, 1);
}